コード例 #1
0
ファイル: jcapistd.cs プロジェクト: JoshDullen/libjpeg.net
		// Write some scanlines of data to the JPEG compressor.
		//
		// The return value will be the number of lines actually written.
		// This should be less than the supplied num_lines only in case that
		// the data destination module has requested suspension of the compressor,
		// or if more than image_height scanlines are passed in.
		//
		// Note: we warn about excess calls to jpeg_write_scanlines() since
		// this likely signals an application programmer error. However,
		// excess scanlines passed in the last valid call are *silently* ignored,
		// so that the application need not adjust num_lines for end-of-image
		// when using a multiple-scanline buffer.
		public static uint jpeg_write_scanlines(jpeg_compress cinfo, byte[][] scanlines, uint num_lines)
		{
			if(cinfo.global_state!=STATE.CSCANNING) ERREXIT1(cinfo, J_MESSAGE_CODE.JERR_BAD_STATE, cinfo.global_state);
			if(cinfo.next_scanline>=cinfo.image_height) WARNMS(cinfo, J_MESSAGE_CODE.JWRN_TOO_MUCH_DATA);

			// Call progress monitor hook if present
			if(cinfo.progress!=null)
			{
				cinfo.progress.pass_counter=(int)cinfo.next_scanline;
				cinfo.progress.pass_limit=(int)cinfo.image_height;
				cinfo.progress.progress_monitor(cinfo);
			}

			// Give master control module another chance if this is first call to
			// jpeg_write_scanlines. This lets output of the frame/scan headers be
			// delayed so that application can write COM, etc, markers between
			// jpeg_start_compress and jpeg_write_scanlines.
			if(cinfo.master.call_pass_startup) cinfo.master.pass_startup(cinfo);

			// Ignore any extra scanlines at bottom of image.
			uint rows_left=cinfo.image_height-cinfo.next_scanline;
			if(num_lines>rows_left) num_lines=rows_left;

			uint row_ctr=0;
			cinfo.main.process_data(cinfo, scanlines, ref row_ctr, num_lines);
			cinfo.next_scanline+=row_ctr;
			return row_ctr;
		}
コード例 #2
0
ファイル: jcdiffct.cs プロジェクト: JoshDullen/libjpeg.net
		// Initialize for a processing pass.
		static void start_pass_diff(jpeg_compress cinfo, J_BUF_MODE pass_mode)
		{
			jpeg_lossless_c_codec losslsc=(jpeg_lossless_c_codec)cinfo.coef;
			c_diff_controller diff=(c_diff_controller)losslsc.diff_private;

			diff.iMCU_row_num=0;
			start_iMCU_row_c_diff(cinfo);

			switch(pass_mode)
			{
				case J_BUF_MODE.JBUF_PASS_THRU:
					if(diff.whole_image[0]!=null)
						ERREXIT(cinfo, J_MESSAGE_CODE.JERR_BAD_BUFFER_MODE);
					losslsc.compress_data=compress_data_diff;
					break;
#if FULL_SAMP_BUFFER_SUPPORTED
				case J_BUF_MODE.JBUF_SAVE_AND_PASS:
					if(diff.whole_image[0]==null)
						ERREXIT(cinfo, J_MESSAGE_CODE.JERR_BAD_BUFFER_MODE);
					losslsc.compress_data=compress_first_pass_diff;
					break;
				case J_BUF_MODE.JBUF_CRANK_DEST:
					if(diff.whole_image[0]==null)
						ERREXIT(cinfo, J_MESSAGE_CODE.JERR_BAD_BUFFER_MODE);
					losslsc.compress_data=compress_output_diff;
					break;
#endif
				default:
					ERREXIT(cinfo, J_MESSAGE_CODE.JERR_BAD_BUFFER_MODE);
					break;
			}
		}
コード例 #3
0
ファイル: jcscale.cs プロジェクト: JoshDullen/libjpeg.net
		static void scaler_start_pass(jpeg_compress cinfo)
		{
			jpeg_lossless_c_codec losslsc=(jpeg_lossless_c_codec)cinfo.coef;

			// Set scaler function based on Pt
			if(cinfo.Al!=0) losslsc.scaler_scale=simple_downscale;
			else losslsc.scaler_scale=noscale;
		}
コード例 #4
0
ファイル: jcmaster.cs プロジェクト: JoshDullen/libjpeg.net
		// Support routines that do various essential calculations.

		// Do computations that are needed before master selection phase
		static void initial_setup(jpeg_compress cinfo)
		{
			// Sanity check on image dimensions
			if(cinfo.image_height<=0||cinfo.image_width<=0||cinfo.num_components<=0||cinfo.input_components<=0)
				ERREXIT(cinfo, J_MESSAGE_CODE.JERR_EMPTY_IMAGE);

			// Make sure image isn't bigger than I can handle
			if(cinfo.image_height>JPEG_MAX_DIMENSION||cinfo.image_width>JPEG_MAX_DIMENSION)
				ERREXIT1(cinfo, J_MESSAGE_CODE.JERR_IMAGE_TOO_BIG, JPEG_MAX_DIMENSION);

			// Width of an input scanline must be representable as uint.
			long samplesperrow=cinfo.image_width*cinfo.input_components;
			if(samplesperrow<0||samplesperrow>uint.MaxValue) ERREXIT(cinfo, J_MESSAGE_CODE.JERR_WIDTH_OVERFLOW);

			// For now, precision must match compiled-in value...
			if(cinfo.data_precision!=BITS_IN_JSAMPLE) ERREXIT1(cinfo, J_MESSAGE_CODE.JERR_BAD_PRECISION, cinfo.data_precision);

			// Check that number of components won't exceed internal array sizes
			if(cinfo.num_components>MAX_COMPONENTS) ERREXIT2(cinfo, J_MESSAGE_CODE.JERR_COMPONENT_COUNT, cinfo.num_components, MAX_COMPONENTS);

			// Compute maximum sampling factors; check factor validity
			cinfo.max_h_samp_factor=1;
			cinfo.max_v_samp_factor=1;
			for(int ci=0; ci<cinfo.num_components; ci++)
			{
				jpeg_component_info compptr=cinfo.comp_info[ci];
				if(compptr.h_samp_factor<=0||compptr.h_samp_factor>MAX_SAMP_FACTOR||compptr.v_samp_factor<=0||compptr.v_samp_factor>MAX_SAMP_FACTOR)
					ERREXIT(cinfo, J_MESSAGE_CODE.JERR_BAD_SAMPLING);
				cinfo.max_h_samp_factor=Math.Max(cinfo.max_h_samp_factor, compptr.h_samp_factor);
				cinfo.max_v_samp_factor=Math.Max(cinfo.max_v_samp_factor, compptr.v_samp_factor);
			}

			// Compute dimensions of components
			uint DCT_size=cinfo.DCT_size;
			for(int ci=0; ci<cinfo.num_components; ci++)
			{
				jpeg_component_info compptr=cinfo.comp_info[ci];
				// Fill in the correct component_index value; don't rely on application
				compptr.component_index=ci;
				// For compression, we never do any codec-based processing.
				compptr.DCT_scaled_size=DCT_size;
				// Size in blocks
				compptr.width_in_blocks=(uint)jdiv_round_up(cinfo.image_width*compptr.h_samp_factor, cinfo.max_h_samp_factor*DCT_size);
				compptr.height_in_blocks=(uint)jdiv_round_up(cinfo.image_height*compptr.v_samp_factor, cinfo.max_v_samp_factor*DCT_size);
				// Size in samples
				compptr.downsampled_width=(uint)jdiv_round_up(cinfo.image_width*compptr.h_samp_factor, cinfo.max_h_samp_factor);
				compptr.downsampled_height=(uint)jdiv_round_up(cinfo.image_height*compptr.v_samp_factor, cinfo.max_v_samp_factor);
				// Mark component needed (this flag isn't actually used for compression)
				compptr.component_needed=true;
			}

			// Compute number of fully interleaved MCU rows (number of times that
			// main controller will call coefficient controller).
			cinfo.total_iMCU_rows=(uint)jdiv_round_up(cinfo.image_height, cinfo.max_v_samp_factor*DCT_size);
		}
コード例 #5
0
        // Alternate entry point to write raw data.
        // Processes exactly one iMCU row per call, unless suspended.
        public static uint jpeg_write_raw_data(jpeg_compress cinfo, byte[][][] data, uint num_lines)
        {
            if (cinfo.global_state != STATE.CRAW_OK)
            {
                ERREXIT1(cinfo, J_MESSAGE_CODE.JERR_BAD_STATE, cinfo.global_state);
            }
            if (cinfo.next_scanline >= cinfo.image_height)
            {
                WARNMS(cinfo, J_MESSAGE_CODE.JWRN_TOO_MUCH_DATA);
                return(0);
            }

            // Call progress monitor hook if present
            if (cinfo.progress != null)
            {
                cinfo.progress.pass_counter = (int)cinfo.next_scanline;
                cinfo.progress.pass_limit   = (int)cinfo.image_height;
                cinfo.progress.progress_monitor(cinfo);
            }

            // Give master control module another chance if this is first call to
            // jpeg_write_raw_data. This lets output of the frame/scan headers be
            // delayed so that application can write COM, etc, markers between
            // jpeg_start_compress and jpeg_write_raw_data.
            if (cinfo.master.call_pass_startup)
            {
                cinfo.master.pass_startup(cinfo);
            }

            // Verify that at least one iMCU row has been passed.
            uint lines_per_iMCU_row = (uint)cinfo.max_v_samp_factor * cinfo.DCT_size;

            if (num_lines < lines_per_iMCU_row)
            {
                ERREXIT(cinfo, J_MESSAGE_CODE.JERR_BUFFER_SIZE);
            }

            // Directly compress the row.
            if (!cinfo.coef.compress_data(cinfo, data))
            {
                return(0);                                                   // If compressor did not consume the whole row, suspend processing.
            }
            // OK, we processed one iMCU row.
            cinfo.next_scanline += lines_per_iMCU_row;
            return(lines_per_iMCU_row);
        }
コード例 #6
0
ファイル: jdatadst.cs プロジェクト: JoshDullen/libjpeg.net
		const int OUTPUT_BUF_SIZE=4096;	// choose an efficiently Write'able size

		// Initialize destination --- called by jpeg_start_compress
		// before any data is actually written.
		static void init_destination(jpeg_compress cinfo)
		{
			my_destination_mgr dest=(my_destination_mgr)cinfo.dest;

			// Allocate the output buffer --- it will be released when done with image
			try
			{
				dest.buffer=new byte[OUTPUT_BUF_SIZE];
			}
			catch
			{
				ERREXIT1(cinfo, J_MESSAGE_CODE.JERR_OUT_OF_MEMORY, 4);
			}
			dest.output_bytes=dest.buffer;
			dest.next_output_byte=0;
			dest.free_in_buffer=OUTPUT_BUF_SIZE;
		}
コード例 #7
0
        // Initialize preprocessing controller.
        static void jinit_c_prep_controller(jpeg_compress cinfo, bool need_full_buffer)
        {
            if (need_full_buffer)
            {
                ERREXIT(cinfo, J_MESSAGE_CODE.JERR_BAD_BUFFER_MODE);                              // safety check
            }
            my_prep_controller prep = null;

            try
            {
                prep = new my_prep_controller();
            }
            catch
            {
                ERREXIT1(cinfo, J_MESSAGE_CODE.JERR_OUT_OF_MEMORY, 4);
            }
            cinfo.prep      = prep;
            prep.start_pass = start_pass_prep;

            // Allocate the color conversion buffer.
            // We make the buffer wide enough to allow the downsampler to edge-expand
            // horizontally within the buffer, if it so chooses.
            if (cinfo.downsample.need_context_rows)
            {
                // Set up to provide context rows
#if CONTEXT_ROWS_SUPPORTED
                prep.pre_process_data = pre_process_context;
                create_context_buffer(cinfo);
#else
                ERREXIT(cinfo, J_MESSAGE_CODE.JERR_NOT_COMPILED);
#endif
            }
            else
            {
                // No context, just make it tall enough for one row group
                prep.pre_process_data = pre_process_data;
                for (int ci = 0; ci < cinfo.num_components; ci++)
                {
                    jpeg_component_info compptr = cinfo.comp_info[ci];
                    prep.color_buf[ci] = alloc_sarray(cinfo,
                                                      (uint)(((int)compptr.width_in_blocks * cinfo.DCT_size * cinfo.max_h_samp_factor) / compptr.h_samp_factor),
                                                      (uint)cinfo.max_v_samp_factor);
                }
            }
        }
コード例 #8
0
ファイル: jcprepct.cs プロジェクト: JoshDullen/libjpeg.net
		// Initialize for a processing pass.
		static void start_pass_prep(jpeg_compress cinfo, J_BUF_MODE pass_mode)
		{
			my_prep_controller prep=(my_prep_controller)cinfo.prep;

			if(pass_mode!=J_BUF_MODE.JBUF_PASS_THRU) ERREXIT(cinfo, J_MESSAGE_CODE.JERR_BAD_BUFFER_MODE);

			// Initialize total-height counter for detecting bottom of image
			prep.rows_to_go=cinfo.image_height;
			// Mark the conversion buffer empty
			prep.next_buf_row=0;
#if CONTEXT_ROWS_SUPPORTED
			// Preset additional state variables for context mode.
			// These aren't used in non-context mode, so we needn't test which mode.
			prep.this_row_group=0;
			// Set next_buf_stop to stop after two row groups have been read in.
			prep.next_buf_stop=2*cinfo.max_v_samp_factor;
#endif
		}
コード例 #9
0
        // Process some data in the first pass of a multi-pass case.
        // We process the equivalent of one fully interleaved MCU row ("iMCU" row)
        // per call, ie, v_samp_factor rows for each component in the image.
        // This amount of data is read from the source buffer and saved into the arrays.
        //
        // We must also emit the data to the compressor. This is conveniently
        // done by calling compress_output_diff() after we've loaded the current strip
        // of the arrays.
        //
        // NB: input_buf contains a plane for each component in image. All components
        // are loaded into the arrays in this pass. However, it may be that
        // only a subset of the components are emitted to the compressor during
        // this first pass; be careful about looking at the scan-dependent variables
        // (MCU dimensions, etc).
        static bool compress_first_pass_diff(jpeg_compress cinfo, byte[][][] input_buf)
        {
            jpeg_lossless_c_codec losslsc = (jpeg_lossless_c_codec)cinfo.coef;
            c_diff_controller     diff    = (c_diff_controller)losslsc.diff_private;

            uint last_iMCU_row = cinfo.total_iMCU_rows - 1;

            for (int ci = 0; ci < cinfo.num_components; ci++)
            {
                jpeg_component_info compptr = cinfo.comp_info[ci];

                // Count non-dummy sample rows in this iMCU row.
                int samp_rows;
                if (diff.iMCU_row_num < last_iMCU_row)
                {
                    samp_rows = compptr.v_samp_factor;
                }
                else
                {
                    // NB: can't use last_row_height here, since may not be set!
                    samp_rows = (int)(compptr.height_in_blocks % compptr.v_samp_factor);
                    if (samp_rows == 0)
                    {
                        samp_rows = compptr.v_samp_factor;
                    }
                }

                uint samps_across = compptr.width_in_blocks;

                // Perform point transform scaling and prediction/differencing for all
                // non-dummy rows in this iMCU row. Each call on these functions
                // process a complete row of samples.
                for (int samp_row = 0; samp_row < samp_rows; samp_row++)
                {
                    Array.Copy(input_buf[ci][samp_row], diff.whole_image[ci][samp_row + diff.iMCU_row_num * compptr.v_samp_factor], samps_across);
                }
            }

            // NB: compress_output will increment iMCU_row_num if successful.
            // A suspension return will result in redoing all the work above next time.

            // Emit data to the compressor, sharing code with subsequent passes
            return(compress_output_diff(cinfo, input_buf));
        }
コード例 #10
0
        // Process some data in the simple no-context case.
        //
        // Preprocessor output data is counted in "row groups". A row group
        // is defined to be v_samp_factor sample rows of each component.
        // Downsampling will produce this much data from each max_v_samp_factor input rows.
        static void pre_process_data(jpeg_compress cinfo, byte[][] input_buf, ref uint in_row_ctr, uint in_rows_avail, byte[][][] output_buf, ref uint out_row_group_ctr, uint out_row_groups_avail)
        {
            my_prep_controller prep = (my_prep_controller)cinfo.prep;

            while (in_row_ctr < in_rows_avail && out_row_group_ctr < out_row_groups_avail)
            {
                // Do color conversion to fill the conversion buffer.
                uint inrows  = in_rows_avail - in_row_ctr;
                int  numrows = cinfo.max_v_samp_factor - prep.next_buf_row;
                numrows = (int)Math.Min((uint)numrows, inrows);
                cinfo.cconvert.color_convert(cinfo, input_buf, in_row_ctr, prep.color_buf, (uint)prep.next_buf_row, numrows);
                in_row_ctr        += (uint)numrows;
                prep.next_buf_row += numrows;
                prep.rows_to_go   -= (uint)numrows;
                // If at bottom of image, pad to fill the conversion buffer.
                if (prep.rows_to_go == 0 && prep.next_buf_row < cinfo.max_v_samp_factor)
                {
                    for (int ci = 0; ci < cinfo.num_components; ci++)
                    {
                        expand_bottom_edge(prep.color_buf[ci], cinfo.image_width, prep.next_buf_row, cinfo.max_v_samp_factor);
                    }
                    prep.next_buf_row = cinfo.max_v_samp_factor;
                }
                // If we've filled the conversion buffer, empty it.
                if (prep.next_buf_row == cinfo.max_v_samp_factor)
                {
                    cinfo.downsample.downsample(cinfo, prep.color_buf, 0, output_buf, out_row_group_ctr);
                    prep.next_buf_row = 0;
                    out_row_group_ctr++;
                }
                // If at bottom of image, pad the output to a full iMCU height.
                // Note we assume the caller is providing a one-iMCU-height output buffer!
                if (prep.rows_to_go == 0 && out_row_group_ctr < out_row_groups_avail)
                {
                    for (int ci = 0; ci < cinfo.num_components; ci++)
                    {
                        jpeg_component_info compptr = cinfo.comp_info[ci];
                        expand_bottom_edge(output_buf[ci], compptr.width_in_blocks * cinfo.DCT_size, (int)(out_row_group_ctr * compptr.v_samp_factor), (int)(out_row_groups_avail * compptr.v_samp_factor));
                    }
                    out_row_group_ctr = out_row_groups_avail;
                    break; // can exit outer loop without test
                }
            }              // while(...)
        }
コード例 #11
0
ファイル: jdatadst.cs プロジェクト: mikel785/libjpeg.net
        // Empty the output buffer --- called whenever buffer fills up.
        //
        // In typical applications, this should write the entire output buffer
        // (ignoring the current state of next_output_byte & free_in_buffer),
        // reset the pointer & count to the start of the buffer, and return true
        // indicating that the buffer has been dumped.
        //
        // In applications that need to be able to suspend compression due to output
        // overrun, a false return indicates that the buffer cannot be emptied now.
        // In this situation, the compressor will return to its caller (possibly with
        // an indication that it has not accepted all the supplied scanlines). The
        // application should resume compression after it has made more room in the
        // output buffer. Note that there are substantial restrictions on the use of
        // suspension --- see the documentation.
        //
        // When suspending, the compressor will back up to a convenient restart point
        // (typically the start of the current MCU). next_output_byte & free_in_buffer
        // indicate where the restart point will be if the current call returns false.
        // Data beyond this point will be regenerated after resumption, so do not
        // write it out when emptying the buffer externally.
        static bool empty_output_buffer(jpeg_compress cinfo)
        {
            my_destination_mgr dest = (my_destination_mgr)cinfo.dest;

            try
            {
                dest.outfile.Write(dest.buffer, 0, OUTPUT_BUF_SIZE);
            }
            catch
            {
                ERREXIT(cinfo, J_MESSAGE_CODE.JERR_FILE_WRITE);
            }

            dest.output_bytes     = dest.buffer;
            dest.next_output_byte = 0;
            dest.free_in_buffer   = OUTPUT_BUF_SIZE;

            return(true);
        }
コード例 #12
0
ファイル: jdatadst.cs プロジェクト: mikel785/libjpeg.net
        // Terminate destination --- called by jpeg_finish_compress
        // after all data has been written. Usually needs to flush buffer.
        //
        // NB: *not* called by jpeg_abort or jpeg_destroy; surrounding
        // application must deal with any cleanup that should happen even
        // for error exit.
        static void term_destination(jpeg_compress cinfo)
        {
            my_destination_mgr dest = (my_destination_mgr)cinfo.dest;
            int datacount           = OUTPUT_BUF_SIZE - (int)dest.free_in_buffer;

            // Write any data remaining in the buffer
            if (datacount > 0)
            {
                try
                {
                    dest.outfile.Write(dest.buffer, 0, datacount);
                }
                catch
                {
                    ERREXIT(cinfo, J_MESSAGE_CODE.JERR_FILE_WRITE);
                }
            }
            dest.outfile.Flush();
        }
コード例 #13
0
ファイル: jdatadst.cs プロジェクト: JoshDullen/libjpeg.net
		// Empty the output buffer --- called whenever buffer fills up.
		//
		// In typical applications, this should write the entire output buffer
		// (ignoring the current state of next_output_byte & free_in_buffer),
		// reset the pointer & count to the start of the buffer, and return true
		// indicating that the buffer has been dumped.
		//
		// In applications that need to be able to suspend compression due to output
		// overrun, a false return indicates that the buffer cannot be emptied now.
		// In this situation, the compressor will return to its caller (possibly with
		// an indication that it has not accepted all the supplied scanlines). The
		// application should resume compression after it has made more room in the
		// output buffer. Note that there are substantial restrictions on the use of
		// suspension --- see the documentation.
		//
		// When suspending, the compressor will back up to a convenient restart point
		// (typically the start of the current MCU). next_output_byte & free_in_buffer
		// indicate where the restart point will be if the current call returns false.
		// Data beyond this point will be regenerated after resumption, so do not
		// write it out when emptying the buffer externally.
		static bool empty_output_buffer(jpeg_compress cinfo)
		{
			my_destination_mgr dest=(my_destination_mgr)cinfo.dest;

			try
			{
				dest.outfile.Write(dest.buffer, 0, OUTPUT_BUF_SIZE);
			}
			catch
			{
				ERREXIT(cinfo, J_MESSAGE_CODE.JERR_FILE_WRITE);
			}

			dest.output_bytes=dest.buffer;
			dest.next_output_byte=0;
			dest.free_in_buffer=OUTPUT_BUF_SIZE;

			return true;
		}
コード例 #14
0
        // Write some scanlines of data to the JPEG compressor.
        //
        // The return value will be the number of lines actually written.
        // This should be less than the supplied num_lines only in case that
        // the data destination module has requested suspension of the compressor,
        // or if more than image_height scanlines are passed in.
        //
        // Note: we warn about excess calls to jpeg_write_scanlines() since
        // this likely signals an application programmer error. However,
        // excess scanlines passed in the last valid call are *silently* ignored,
        // so that the application need not adjust num_lines for end-of-image
        // when using a multiple-scanline buffer.
        public static uint jpeg_write_scanlines(jpeg_compress cinfo, byte[][] scanlines, uint num_lines)
        {
            if (cinfo.global_state != STATE.CSCANNING)
            {
                ERREXIT1(cinfo, J_MESSAGE_CODE.JERR_BAD_STATE, cinfo.global_state);
            }
            if (cinfo.next_scanline >= cinfo.image_height)
            {
                WARNMS(cinfo, J_MESSAGE_CODE.JWRN_TOO_MUCH_DATA);
            }

            // Call progress monitor hook if present
            if (cinfo.progress != null)
            {
                cinfo.progress.pass_counter = (int)cinfo.next_scanline;
                cinfo.progress.pass_limit   = (int)cinfo.image_height;
                cinfo.progress.progress_monitor(cinfo);
            }

            // Give master control module another chance if this is first call to
            // jpeg_write_scanlines. This lets output of the frame/scan headers be
            // delayed so that application can write COM, etc, markers between
            // jpeg_start_compress and jpeg_write_scanlines.
            if (cinfo.master.call_pass_startup)
            {
                cinfo.master.pass_startup(cinfo);
            }

            // Ignore any extra scanlines at bottom of image.
            uint rows_left = cinfo.image_height - cinfo.next_scanline;

            if (num_lines > rows_left)
            {
                num_lines = rows_left;
            }

            uint row_ctr = 0;

            cinfo.main.process_data(cinfo, scanlines, ref row_ctr, num_lines);
            cinfo.next_scanline += row_ctr;
            return(row_ctr);
        }
コード例 #15
0
ファイル: jcparam.cs プロジェクト: mikel785/libjpeg.net
        // Quantization table setup routines

        // Define a quantization table equal to the basic_table times
        // a scale factor (given as a percentage).
        // If force_baseline is true, the computed quantization table entries
        // are limited to 1..255 for JPEG baseline compatibility.
        public static void jpeg_add_quant_table(jpeg_compress cinfo, int which_tbl, uint[] basic_table, int scale_factor, bool force_baseline)
        {
            // Safety check to ensure start_compress not called yet.
            if (cinfo.global_state != STATE.CSTART)
            {
                ERREXIT1(cinfo, J_MESSAGE_CODE.JERR_BAD_STATE, cinfo.global_state);
            }

            if (which_tbl < 0 || which_tbl >= NUM_QUANT_TBLS)
            {
                ERREXIT1(cinfo, J_MESSAGE_CODE.JERR_DQT_INDEX, which_tbl);
            }

            if (cinfo.quant_tbl_ptrs[which_tbl] == null)
            {
                cinfo.quant_tbl_ptrs[which_tbl] = jpeg_alloc_quant_table(cinfo);
            }

            for (int i = 0; i < DCTSIZE2; i++)
            {
                int temp = ((int)basic_table[i] * scale_factor + 50) / 100;

                // limit the values to the valid range
                if (temp <= 0)
                {
                    temp = 1;
                }
                if (temp > 32767)
                {
                    temp = 32767;                          // max quantizer needed for 12 bits
                }
                if (force_baseline && temp > 255)
                {
                    temp = 255;                                        // limit to baseline range if requested
                }
                cinfo.quant_tbl_ptrs[which_tbl].quantval[i] = (ushort)temp;
            }

            // Initialize sent_table false so table will be written to JPEG file.
            cinfo.quant_tbl_ptrs[which_tbl].sent_table = false;
        }
コード例 #16
0
        // Process some data in subsequent passes of a multi-pass case.
        // We process the equivalent of one fully interleaved MCU row ("iMCU" row)
        // per call, ie, v_samp_factor rows for each component in the scan.
        // The data is obtained from the arrays and fed to the compressor.
        // Returns true if the iMCU row is completed, false if suspended.
        //
        // NB: input_buf is ignored; it is likely to be a null pointer.
        static bool compress_output_diff(jpeg_compress cinfo, byte[][][] input_buf)
        {
            jpeg_lossless_c_codec losslsc = (jpeg_lossless_c_codec)cinfo.coef;
            c_diff_controller     diff    = (c_diff_controller)losslsc.diff_private;

            byte[][][] buffer     = new byte[MAX_COMPONENTS][][];
            int[]      buffer_ind = new int[MAX_COMPONENTS];

            // Align the buffers for the components used in this scan.
            // NB: during first pass, this is safe only because the buffers will
            // already be aligned properly, so jmemmgr.cs won't need to do any I/O.
            for (int comp = 0; comp < cinfo.comps_in_scan; comp++)
            {
                jpeg_component_info compptr = cinfo.cur_comp_info[comp];
                int ci = compptr.component_index;
                buffer[ci]     = diff.whole_image[ci];
                buffer_ind[ci] = (int)diff.iMCU_row_num * compptr.v_samp_factor;
            }

            return(compress_data_diff(cinfo, buffer, buffer_ind));
        }
コード例 #17
0
ファイル: jcsample.cs プロジェクト: mikel785/libjpeg.net
        // Downsample pixel values of a single component.
        // This version handles the common case of 2:1 horizontal and 1:1 vertical,
        // without smoothing.
        //
        // A note about the "bias" calculations: when rounding fractional values to
        // integer, we do not want to always round 0.5 up to the next integer.
        // If we did that, we'd introduce a noticeable bias towards larger values.
        // Instead, this code is arranged so that 0.5 will be rounded up or down at
        // alternate pixel locations (a simple ordered dither pattern).
        static void h2v1_downsample(jpeg_compress cinfo, jpeg_component_info compptr, byte[][] input_data, uint in_row_index, byte[][] output_data, uint out_row_index)
        {
            uint output_cols = compptr.width_in_blocks * cinfo.DCT_size;

            // Expand input data enough to let all the output samples be generated
            // by the standard loop. Special-casing padded output would be more
            // efficient.
            expand_right_edge(input_data, in_row_index, cinfo.max_v_samp_factor, cinfo.image_width, output_cols * 2);

            for (int outrow = 0; outrow < compptr.v_samp_factor; outrow++)
            {
                byte[] outptr = output_data[out_row_index + outrow];
                byte[] inptr  = input_data[in_row_index + outrow];
                int    bias   = 0;          // bias = 0,1,0,1,... for successive samples
                for (uint outcol = 0, ind = 0; outcol < output_cols; outcol++, ind += 2)
                {
                    outptr[outcol] = (byte)((inptr[ind] + inptr[ind + 1] + bias) >> 1);
                    bias          ^= 1;          // 0=>1, 1=>0
                }
            }
        }
コード例 #18
0
        // Initialize for a processing pass.
        static void start_pass_prep(jpeg_compress cinfo, J_BUF_MODE pass_mode)
        {
            my_prep_controller prep = (my_prep_controller)cinfo.prep;

            if (pass_mode != J_BUF_MODE.JBUF_PASS_THRU)
            {
                ERREXIT(cinfo, J_MESSAGE_CODE.JERR_BAD_BUFFER_MODE);
            }

            // Initialize total-height counter for detecting bottom of image
            prep.rows_to_go = cinfo.image_height;
            // Mark the conversion buffer empty
            prep.next_buf_row = 0;
#if CONTEXT_ROWS_SUPPORTED
            // Preset additional state variables for context mode.
            // These aren't used in non-context mode, so we needn't test which mode.
            prep.this_row_group = 0;
            // Set next_buf_stop to stop after two row groups have been read in.
            prep.next_buf_stop = 2 * cinfo.max_v_samp_factor;
#endif
        }
コード例 #19
0
ファイル: jcapistd.cs プロジェクト: JoshDullen/libjpeg.net
		// Compression initialization.
		// Before calling this, all parameters and a data destination must be set up.
		//
		// We require a write_all_tables parameter as a failsafe check when writing
		// multiple datastreams from the same compression object. Since prior runs
		// will have left all the tables marked sent_table=true, a subsequent run
		// would emit an abbreviated stream (no tables) by default. This may be what
		// is wanted, but for safety's sake it should not be the default behavior:
		// programmers should have to make a deliberate choice to emit abbreviated
		// images. Therefore the documentation and examples should encourage people
		// to pass write_all_tables=true; then it will take active thought to do the
		// wrong thing.
		public static void jpeg_start_compress(jpeg_compress cinfo, bool write_all_tables)
		{
			if(cinfo.global_state!=STATE.CSTART) ERREXIT1(cinfo, J_MESSAGE_CODE.JERR_BAD_STATE, cinfo.global_state);

			if(write_all_tables) jpeg_suppress_tables(cinfo, false); // mark all tables to be written

			// (Re)initialize error mgr and destination modules 
			cinfo.err.reset_error_mgr(cinfo);
			cinfo.dest.init_destination(cinfo);

			// Perform master selection of active modules
			jinit_compress_master(cinfo);

			// Set up for the first pass
			cinfo.master.prepare_for_pass(cinfo);

			// Ready for application to drive first pass through jpeg_write_scanlines
			// or jpeg_write_raw_data.
			cinfo.next_scanline=0;
			cinfo.global_state=(cinfo.raw_data_in?STATE.CRAW_OK:STATE.CSCANNING);
		}
コード例 #20
0
ファイル: jdatadst.cs プロジェクト: mikel785/libjpeg.net
        // Prepare for output to a stdio stream.
        // The caller must have already opened the stream, and is responsible
        // for jpeg_destination_mgr it after finishing compression.
        public static void jpeg_stdio_dest(jpeg_compress cinfo, Stream outfile)
        {
            my_destination_mgr dest;

            // The destination object is made permanent so that multiple JPEG images
            // can be written to the same file without re-executing jpeg_stdio_dest.
            // This makes it dangerous to use this manager and a different destination
            // manager serially with the same JPEG object, because their private object
            // sizes may be different. Caveat programmer.
            if (cinfo.dest == null)
            {
                // first time for this JPEG object?
                cinfo.dest = new my_destination_mgr();
            }

            dest = (my_destination_mgr)cinfo.dest;
            dest.init_destination    = init_destination;
            dest.empty_output_buffer = empty_output_buffer;
            dest.term_destination    = term_destination;
            dest.outfile             = outfile;
        }
コード例 #21
0
        // Initialize for a processing pass.
        static void start_pass_diff(jpeg_compress cinfo, J_BUF_MODE pass_mode)
        {
            jpeg_lossless_c_codec losslsc = (jpeg_lossless_c_codec)cinfo.coef;
            c_diff_controller     diff    = (c_diff_controller)losslsc.diff_private;

            diff.iMCU_row_num = 0;
            start_iMCU_row_c_diff(cinfo);

            switch (pass_mode)
            {
            case J_BUF_MODE.JBUF_PASS_THRU:
                if (diff.whole_image[0] != null)
                {
                    ERREXIT(cinfo, J_MESSAGE_CODE.JERR_BAD_BUFFER_MODE);
                }
                losslsc.compress_data = compress_data_diff;
                break;

#if FULL_SAMP_BUFFER_SUPPORTED
            case J_BUF_MODE.JBUF_SAVE_AND_PASS:
                if (diff.whole_image[0] == null)
                {
                    ERREXIT(cinfo, J_MESSAGE_CODE.JERR_BAD_BUFFER_MODE);
                }
                losslsc.compress_data = compress_first_pass_diff;
                break;

            case J_BUF_MODE.JBUF_CRANK_DEST:
                if (diff.whole_image[0] == null)
                {
                    ERREXIT(cinfo, J_MESSAGE_CODE.JERR_BAD_BUFFER_MODE);
                }
                losslsc.compress_data = compress_output_diff;
                break;
#endif
            default:
                ERREXIT(cinfo, J_MESSAGE_CODE.JERR_BAD_BUFFER_MODE);
                break;
            }
        }
コード例 #22
0
ファイル: jcmaster.cs プロジェクト: mikel785/libjpeg.net
        // Finish up at end of pass.
        static void finish_pass_master(jpeg_compress cinfo)
        {
            my_comp_master master = (my_comp_master)cinfo.master;

            // The entropy coder always needs an end-of-pass call,
            // either to analyze statistics or to flush its output buffer.
            cinfo.coef.entropy_finish_pass(cinfo);

            // Update state for next pass
            switch (master.pass_type)
            {
            case c_pass_type.main_pass:
                // next pass is either output of scan 0 (after optimization)
                // or output of scan 1 (if no optimization).
                master.pass_type = c_pass_type.output_pass;
                if (!cinfo.optimize_coding)
                {
                    master.scan_number++;
                }
                break;

            case c_pass_type.huff_opt_pass:
                // next pass is always output of current scan
                master.pass_type = c_pass_type.output_pass;
                break;

            case c_pass_type.output_pass:
                // next pass is either optimization or output of next scan
                if (cinfo.optimize_coding)
                {
                    master.pass_type = c_pass_type.huff_opt_pass;
                }
                master.scan_number++;
                break;
            }

            master.pass_number++;
        }
コード例 #23
0
ファイル: jcparam.cs プロジェクト: JoshDullen/libjpeg.net
		// Quantization table setup routines

		// Define a quantization table equal to the basic_table times
		// a scale factor (given as a percentage).
		// If force_baseline is true, the computed quantization table entries
		// are limited to 1..255 for JPEG baseline compatibility.
		public static void jpeg_add_quant_table(jpeg_compress cinfo, int which_tbl, uint[] basic_table, int scale_factor, bool force_baseline)
		{
			// Safety check to ensure start_compress not called yet.
			if(cinfo.global_state!=STATE.CSTART) ERREXIT1(cinfo, J_MESSAGE_CODE.JERR_BAD_STATE, cinfo.global_state);

			if(which_tbl<0||which_tbl>=NUM_QUANT_TBLS) ERREXIT1(cinfo, J_MESSAGE_CODE.JERR_DQT_INDEX, which_tbl);

			if(cinfo.quant_tbl_ptrs[which_tbl]==null) cinfo.quant_tbl_ptrs[which_tbl]=jpeg_alloc_quant_table(cinfo);

			for(int i=0; i<DCTSIZE2; i++)
			{
				int temp=((int)basic_table[i]*scale_factor+50)/100;

				// limit the values to the valid range
				if(temp<=0) temp=1;
				if(temp>32767) temp=32767; // max quantizer needed for 12 bits
				if(force_baseline&&temp>255) temp=255; // limit to baseline range if requested
				cinfo.quant_tbl_ptrs[which_tbl].quantval[i]=(ushort)temp;
			}

			// Initialize sent_table false so table will be written to JPEG file.
			cinfo.quant_tbl_ptrs[which_tbl].sent_table=false;
		}
コード例 #24
0
ファイル: jcdiffct.cs プロジェクト: JoshDullen/libjpeg.net
		// Reset within-iMCU-row counters for a new row
		static void start_iMCU_row_c_diff(jpeg_compress cinfo)
		{
			jpeg_lossless_c_codec losslsc=(jpeg_lossless_c_codec)cinfo.coef;
			c_diff_controller diff=(c_diff_controller)losslsc.diff_private;

			// In an interleaved scan, an MCU row is the same as an iMCU row.
			// In a noninterleaved scan, an iMCU row has v_samp_factor MCU rows.
			// But at the bottom of the image, process only what's left.
			if(cinfo.comps_in_scan>1)
			{
				diff.MCU_rows_per_iMCU_row=1;
			}
			else
			{
				if(diff.iMCU_row_num<(cinfo.total_iMCU_rows-1))
					diff.MCU_rows_per_iMCU_row=cinfo.cur_comp_info[0].v_samp_factor;
				else
					diff.MCU_rows_per_iMCU_row=cinfo.cur_comp_info[0].last_row_height;
			}

			diff.mcu_ctr=0;
			diff.MCU_vert_offset=0;
		}
コード例 #25
0
        // Process some data in the context case.
        static void pre_process_context(jpeg_compress cinfo, byte[][] input_buf, ref uint in_row_ctr, uint in_rows_avail, byte[][][] output_buf, ref uint out_row_group_ctr, uint out_row_groups_avail)
        {
            my_prep_controller prep = (my_prep_controller)cinfo.prep;
            int buf_height          = cinfo.max_v_samp_factor * 3;
            int rgroup_height       = cinfo.max_v_samp_factor;

            while (out_row_group_ctr < out_row_groups_avail)
            {
                if (in_row_ctr < in_rows_avail)
                {
                    // Do color conversion to fill the conversion buffer.
                    uint inrows  = in_rows_avail - in_row_ctr;
                    int  numrows = prep.next_buf_stop - prep.next_buf_row;
                    numrows = (int)Math.Min((uint)numrows, inrows);
                    cinfo.cconvert.color_convert(cinfo, input_buf, in_row_ctr, prep.color_buf, (uint)rgroup_height + (uint)prep.next_buf_row, numrows);

                    // Pad at top of image, if first time through
                    if (prep.rows_to_go == cinfo.image_height)
                    {
                        for (int ci = 0; ci < cinfo.num_components; ci++)
                        {
                            for (int row = 1; row <= cinfo.max_v_samp_factor; row++)
                            {
                                jcopy_sample_rows(prep.color_buf[ci], rgroup_height, prep.color_buf[ci], rgroup_height - row, 1, cinfo.image_width);
                            }
                        }
                    }
                    in_row_ctr        += (uint)numrows;
                    prep.next_buf_row += numrows;
                    prep.rows_to_go   -= (uint)numrows;
                }
                else
                {
                    // Return for more data, unless we are at the bottom of the image.
                    if (prep.rows_to_go != 0)
                    {
                        break;
                    }

                    // When at bottom of image, pad to fill the conversion buffer.
                    if (prep.next_buf_row < prep.next_buf_stop)
                    {
                        for (int ci = 0; ci < cinfo.num_components; ci++)
                        {
                            expand_bottom_edge(prep.color_buf[ci], cinfo.image_width, rgroup_height + prep.next_buf_row, rgroup_height + prep.next_buf_stop);
                        }

                        prep.next_buf_row = prep.next_buf_stop;
                    }
                }

                // If we've gotten enough data, downsample a row group.
                if (prep.next_buf_row == prep.next_buf_stop)
                {
                    cinfo.downsample.downsample(cinfo, prep.color_buf, (uint)rgroup_height + (uint)prep.this_row_group, output_buf, out_row_group_ctr);
                    out_row_group_ctr++;

                    // Advance pointers with wraparound as necessary.
                    prep.this_row_group += cinfo.max_v_samp_factor;
                    if (prep.this_row_group >= buf_height)
                    {
                        prep.this_row_group = 0;
                    }
                    if (prep.next_buf_row >= buf_height)
                    {
                        prep.next_buf_row = 0;
                    }
                    prep.next_buf_stop = prep.next_buf_row + cinfo.max_v_samp_factor;
                }
            }             // while(...)
        }
コード例 #26
0
ファイル: jcparam.cs プロジェクト: mikel785/libjpeg.net
        // Create a recommended progressive-JPEG script.
        // cinfo.num_components and cinfo.jpeg_color_space must be correct.
        public static void jpeg_simple_progression(jpeg_compress cinfo)
        {
            int ncomps = cinfo.num_components;

            // Safety check to ensure start_compress not called yet.
            if (cinfo.global_state != STATE.CSTART)
            {
                ERREXIT1(cinfo, J_MESSAGE_CODE.JERR_BAD_STATE, cinfo.global_state);
            }

            // Figure space needed for script. Calculation must match code below!
            int nscans;

            if (ncomps == 3 && cinfo.jpeg_color_space == J_COLOR_SPACE.JCS_YCbCr)
            {             // Custom script for YCbCr color images.
                nscans = 10;
            }
            else
            {
                // All-purpose script for other color spaces.
                if (ncomps > MAX_COMPS_IN_SCAN)
                {
                    nscans = 6 * ncomps;                                      // 2 DC + 4 AC scans per component
                }
                else
                {
                    nscans = 2 + 4 * ncomps;            // 2 DC scans; 4 AC scans per component
                }
            }

            // Allocate space for script.
            // We need to put it in the permanent pool in case the application performs
            // multiple compressions without changing the settings. To avoid a memory
            // leak if jpeg_simple_progression is called repeatedly for the same JPEG
            // object, we try to re-use previously allocated space, and we allocate
            // enough space to handle YCbCr even if initially asked for grayscale.
            if (cinfo.script_space == null || cinfo.script_space_size < nscans)
            {
                cinfo.script_space_size = Math.Max(nscans, 10);

                try
                {
                    cinfo.script_space = new jpeg_scan_info[cinfo.script_space_size];
                    for (int i = 0; i < cinfo.script_space_size; i++)
                    {
                        cinfo.script_space[i] = new jpeg_scan_info();
                    }
                }
                catch
                {
                    ERREXIT1(cinfo, J_MESSAGE_CODE.JERR_OUT_OF_MEMORY, 4);
                }
            }
            jpeg_scan_info[] scanptr = cinfo.script_space;
            int scanptr_ind          = 0;

            cinfo.scan_info = scanptr;
            cinfo.num_scans = nscans;

            if (ncomps == 3 && cinfo.jpeg_color_space == J_COLOR_SPACE.JCS_YCbCr)
            {
                // Custom script for YCbCr color images.
                // Initial DC scan
                scanptr_ind = fill_dc_scans(scanptr, scanptr_ind, ncomps, 0, 1);
                // Initial AC scan: get some luma data out in a hurry
                scanptr_ind = fill_a_scan(scanptr, scanptr_ind, 0, 1, 5, 0, 2);
                // Chroma data is too small to be worth expending many scans on
                scanptr_ind = fill_a_scan(scanptr, scanptr_ind, 2, 1, 63, 0, 1);
                scanptr_ind = fill_a_scan(scanptr, scanptr_ind, 1, 1, 63, 0, 1);
                // Complete spectral selection for luma AC
                scanptr_ind = fill_a_scan(scanptr, scanptr_ind, 0, 6, 63, 0, 2);
                // Refine next bit of luma AC
                scanptr_ind = fill_a_scan(scanptr, scanptr_ind, 0, 1, 63, 2, 1);
                // Finish DC successive approximation
                scanptr_ind = fill_dc_scans(scanptr, scanptr_ind, ncomps, 1, 0);
                // Finish AC successive approximation
                scanptr_ind = fill_a_scan(scanptr, scanptr_ind, 2, 1, 63, 1, 0);
                scanptr_ind = fill_a_scan(scanptr, scanptr_ind, 1, 1, 63, 1, 0);
                // Luma bottom bit comes last since it's usually largest scan
                scanptr_ind = fill_a_scan(scanptr, scanptr_ind, 0, 1, 63, 1, 0);
            }
            else
            {
                // All-purpose script for other color spaces.
                // Successive approximation first pass
                scanptr_ind = fill_dc_scans(scanptr, scanptr_ind, ncomps, 0, 1);
                scanptr_ind = fill_scans(scanptr, scanptr_ind, ncomps, 1, 5, 0, 2);
                scanptr_ind = fill_scans(scanptr, scanptr_ind, ncomps, 6, 63, 0, 2);
                // Successive approximation second pass
                scanptr_ind = fill_scans(scanptr, scanptr_ind, ncomps, 1, 63, 2, 1);
                // Successive approximation final pass
                scanptr_ind = fill_dc_scans(scanptr, scanptr_ind, ncomps, 1, 0);
                scanptr_ind = fill_scans(scanptr, scanptr_ind, ncomps, 1, 63, 1, 0);
            }
        }
コード例 #27
0
ファイル: jcparam.cs プロジェクト: mikel785/libjpeg.net
        // Set the JPEG colorspace, and choose colorspace-dependent default values.
        public static void jpeg_set_colorspace(jpeg_compress cinfo, J_COLOR_SPACE colorspace, J_SUBSAMPLING subsampling)
        {
            // Safety check to ensure start_compress not called yet.
            if (cinfo.global_state != STATE.CSTART)
            {
                ERREXIT1(cinfo, J_MESSAGE_CODE.JERR_BAD_STATE, cinfo.global_state);
            }

            // For all colorspaces, we use Q and Huff tables 0 for luminance components,
            // tables 1 for chrominance components.
            cinfo.jpeg_color_space = colorspace;

            cinfo.write_JFIF_header  = false;                   // No marker for non-JFIF colorspaces
            cinfo.write_Adobe_marker = false;                   // write no Adobe marker by default

            switch (colorspace)
            {
            case J_COLOR_SPACE.JCS_GRAYSCALE:
                cinfo.write_JFIF_header = true;                       // Write a JFIF marker
                cinfo.num_components    = 1;
                // JFIF specifies component ID 1
                SET_COMP(cinfo, 0, 1, 1, 1, 0, 0, 0);
                break;

            case J_COLOR_SPACE.JCS_RGB:
                cinfo.write_Adobe_marker = true;                       // write Adobe marker to flag RGB
                cinfo.num_components     = 3;
                SET_COMP(cinfo, 0, 0x52, 1, 1, 0, 0, 0);               // 0x52 = 'R'
                SET_COMP(cinfo, 1, 0x47, 1, 1, 0, 0, 0);               // 0x47 = 'G'
                SET_COMP(cinfo, 2, 0x42, 1, 1, 0, 0, 0);               // 0x42 = 'B'
                break;

            case J_COLOR_SPACE.JCS_YCbCr:
                cinfo.write_JFIF_header = true;                       // Write a JFIF marker
                cinfo.num_components    = 3;
                // JFIF specifies component IDs 1,2,3
                if (cinfo.lossless || subsampling == J_SUBSAMPLING.JPEG444)
                {
                    SET_COMP(cinfo, 0, 1, 1, 1, 0, 0, 0);
                    SET_COMP(cinfo, 1, 2, 1, 1, 1, 1, 1);
                    SET_COMP(cinfo, 2, 3, 1, 1, 1, 1, 1);
                }
                else if (subsampling == J_SUBSAMPLING.JPEG422)
                {
                    // We default to 2x1 subsamples of chrominance
                    SET_COMP(cinfo, 0, 1, 2, 1, 0, 0, 0);
                    SET_COMP(cinfo, 1, 2, 1, 1, 1, 1, 1);
                    SET_COMP(cinfo, 2, 3, 1, 1, 1, 1, 1);
                }
                else
                {
                    // We default to 2x2 subsamples of chrominance
                    SET_COMP(cinfo, 0, 1, 2, 2, 0, 0, 0);
                    SET_COMP(cinfo, 1, 2, 1, 1, 1, 1, 1);
                    SET_COMP(cinfo, 2, 3, 1, 1, 1, 1, 1);
                }
                break;

            case J_COLOR_SPACE.JCS_CMYK:
                cinfo.write_Adobe_marker = true;                       // write Adobe marker to flag CMYK
                cinfo.num_components     = 4;
                SET_COMP(cinfo, 0, 0x43, 1, 1, 0, 0, 0);               // 0x43 = 'C'
                SET_COMP(cinfo, 1, 0x4D, 1, 1, 0, 0, 0);               // 0x4D = 'M'
                SET_COMP(cinfo, 2, 0x59, 1, 1, 0, 0, 0);               // 0x59 = 'Y'
                SET_COMP(cinfo, 3, 0x4B, 1, 1, 0, 0, 0);               // 0x4B = 'K'
                break;

            case J_COLOR_SPACE.JCS_YCCK:
                cinfo.write_Adobe_marker = true;                       // write Adobe marker to flag YCCK
                cinfo.num_components     = 4;
                if (cinfo.lossless)
                {
                    SET_COMP(cinfo, 0, 1, 1, 1, 0, 0, 0);
                    SET_COMP(cinfo, 1, 2, 1, 1, 1, 1, 1);
                    SET_COMP(cinfo, 2, 3, 1, 1, 1, 1, 1);
                    SET_COMP(cinfo, 3, 4, 1, 1, 0, 0, 0);
                }
                else
                {
                    SET_COMP(cinfo, 0, 1, 2, 2, 0, 0, 0);
                    SET_COMP(cinfo, 1, 2, 1, 1, 1, 1, 1);
                    SET_COMP(cinfo, 2, 3, 1, 1, 1, 1, 1);
                    SET_COMP(cinfo, 3, 4, 2, 2, 0, 0, 0);
                }
                break;

            case J_COLOR_SPACE.JCS_UNKNOWN:
                cinfo.num_components = cinfo.input_components;
                if (cinfo.num_components < 1 || cinfo.num_components > MAX_COMPONENTS)
                {
                    ERREXIT2(cinfo, J_MESSAGE_CODE.JERR_COMPONENT_COUNT, cinfo.num_components, MAX_COMPONENTS);
                }
                for (int ci = 0; ci < cinfo.num_components; ci++)
                {
                    SET_COMP(cinfo, ci, ci, 1, 1, 0, 0, 0);
                }
                break;

            default: ERREXIT(cinfo, J_MESSAGE_CODE.JERR_BAD_J_COLORSPACE); break;
            }
        }
コード例 #28
0
ファイル: jcmaster.cs プロジェクト: JoshDullen/libjpeg.net
		// Special start-of-pass hook.
		// This is called by jpeg_write_scanlines if call_pass_startup is true.
		// In single-pass processing, we need this hook because we don't want to
		// write frame/scan headers during jpeg_start_compress; we want to let the
		// application write COM markers etc. between jpeg_start_compress and the
		// jpeg_write_scanlines loop.
		// In multi-pass processing, this routine is not used.
		static void pass_startup(jpeg_compress cinfo)
		{
			cinfo.master.call_pass_startup=false; // reset flag so call only once

			cinfo.marker.write_frame_header(cinfo);
			cinfo.marker.write_scan_header(cinfo);
		}
コード例 #29
0
ファイル: jcmaster.cs プロジェクト: JoshDullen/libjpeg.net
		// Finish up at end of pass.
		static void finish_pass_master(jpeg_compress cinfo)
		{
			my_comp_master master=(my_comp_master)cinfo.master;

			// The entropy coder always needs an end-of-pass call,
			// either to analyze statistics or to flush its output buffer.
			cinfo.coef.entropy_finish_pass(cinfo);

			// Update state for next pass
			switch(master.pass_type)
			{
				case c_pass_type.main_pass:
					// next pass is either output of scan 0 (after optimization)
					// or output of scan 1 (if no optimization).
					master.pass_type=c_pass_type.output_pass;
					if(!cinfo.optimize_coding) master.scan_number++;
					break;
				case c_pass_type.huff_opt_pass:
					// next pass is always output of current scan
					master.pass_type=c_pass_type.output_pass;
					break;
				case c_pass_type.output_pass:
					// next pass is either optimization or output of next scan
					if(cinfo.optimize_coding) master.pass_type=c_pass_type.huff_opt_pass;
					master.scan_number++;
					break;
			}

			master.pass_number++;
		}
コード例 #30
0
ファイル: jcmaster.cs プロジェクト: JoshDullen/libjpeg.net
		// Verify that the scan script in cinfo.scan_info[] is valid; also
		// determine whether it uses progressive JPEG, and set cinfo.process.
		static void validate_script(jpeg_compress cinfo)
		{
#if C_PROGRESSIVE_SUPPORTED
			int[,] last_bitpos=new int[MAX_COMPONENTS, DCTSIZE2];
			// -1 until that coefficient has been seen; then last Al for it
#endif
			if(cinfo.num_scans<=0) ERREXIT1(cinfo, J_MESSAGE_CODE.JERR_BAD_SCAN_SCRIPT, 0);

#if !C_MULTISCAN_FILES_SUPPORTED
			if(cinfo.num_scans>1) ERREXIT(cinfo, J_MESSAGE_CODE.JERR_NOT_COMPILED);
#endif

			bool[] component_sent=new bool[MAX_COMPONENTS];
			if(cinfo.lossless)
			{
#if C_LOSSLESS_SUPPORTED
				cinfo.process=J_CODEC_PROCESS.JPROC_LOSSLESS;
				for(int ci=0; ci<cinfo.num_components; ci++) component_sent[ci]=false;
#else
				ERREXIT(cinfo, J_MESSAGE_CODE.JERR_NOT_COMPILED);
#endif
			}
			// For sequential JPEG, all scans must have Ss=0, Se=DCTSIZE2-1;
			// for progressive JPEG, no scan can have this.
			else if(cinfo.scan_info[0].Ss!=0||cinfo.scan_info[0].Se!=DCTSIZE2-1)
			{
#if C_PROGRESSIVE_SUPPORTED

				cinfo.process=J_CODEC_PROCESS.JPROC_PROGRESSIVE;
				for(int ci=0; ci<cinfo.num_components; ci++)
					for(int coefi=0; coefi<DCTSIZE2; coefi++) last_bitpos[ci, coefi]=-1;
#else
				ERREXIT(cinfo, J_MESSAGE_CODE.JERR_NOT_COMPILED);
#endif
			}
			else
			{
				cinfo.process=J_CODEC_PROCESS.JPROC_SEQUENTIAL;
				for(int ci=0; ci<cinfo.num_components; ci++) component_sent[ci]=false;
			}

			for(int scanno=1; scanno<=cinfo.num_scans; scanno++)
			{
				jpeg_scan_info scan_info=cinfo.scan_info[scanno-1];

				// Validate component indexes
				int ncomps=scan_info.comps_in_scan;
				if(ncomps<=0||ncomps>MAX_COMPS_IN_SCAN) ERREXIT2(cinfo, J_MESSAGE_CODE.JERR_COMPONENT_COUNT, ncomps, MAX_COMPS_IN_SCAN);
				for(int ci=0; ci<ncomps; ci++)
				{
					int thisi=scan_info.component_index[ci];
					if(thisi<0||thisi>=cinfo.num_components) ERREXIT1(cinfo, J_MESSAGE_CODE.JERR_BAD_SCAN_SCRIPT, scanno);

					// Components must appear in SOF order within each scan
					if(ci>0&&thisi<=scan_info.component_index[ci-1]) ERREXIT1(cinfo, J_MESSAGE_CODE.JERR_BAD_SCAN_SCRIPT, scanno);
				}

				// Validate progression parameters
				int Ss=scan_info.Ss;
				int Se=scan_info.Se;
				int Ah=scan_info.Ah;
				int Al=scan_info.Al;
				if(cinfo.process==J_CODEC_PROCESS.JPROC_LOSSLESS)
				{
#if C_LOSSLESS_SUPPORTED
					// The JPEG spec simply gives the range 0..15 for Al (Pt), but that
					// seems wrong: the upper bound ought to depend on data precision.
					// Perhaps they really meant 0..N-1 for N-bit precision, which is what
					// we allow here.
					if(Ss<1||Ss>7||Se!=0||Ah!=0||Al<0||Al>=cinfo.data_precision) // Ss predictor selector; Al point transform
						ERREXIT1(cinfo, J_MESSAGE_CODE.JERR_BAD_LOSSLESS_SCRIPT, scanno);

					// Make sure components are not sent twice
					for(int ci=0; ci<ncomps; ci++)
					{
						int thisi=scan_info.component_index[ci];
						if(component_sent[thisi]) ERREXIT1(cinfo, J_MESSAGE_CODE.JERR_BAD_SCAN_SCRIPT, scanno);
						component_sent[thisi]=true;
					}
#endif
				}
				else if(cinfo.process==J_CODEC_PROCESS.JPROC_PROGRESSIVE)
				{
#if C_PROGRESSIVE_SUPPORTED
					// The JPEG spec simply gives the ranges 0..13 for Ah and Al, but that
					// seems wrong: the upper bound ought to depend on data precision.
					// Perhaps they really meant 0..N+1 for N-bit precision.
					// Here we allow 0..10 for 8-bit data; Al larger than 10 results in
					// out-of-range reconstructed DC values during the first DC scan,
					// which might cause problems for some decoders.
					const int MAX_AH_AL=10;
					if(Ss<0||Ss>=DCTSIZE2||Se<Ss||Se>=DCTSIZE2||
					Ah<0||Ah>MAX_AH_AL||Al<0||Al>MAX_AH_AL) ERREXIT1(cinfo, J_MESSAGE_CODE.JERR_BAD_PROG_SCRIPT, scanno);
					if(Ss==0)
					{
						if(Se!=0) ERREXIT1(cinfo, J_MESSAGE_CODE.JERR_BAD_PROG_SCRIPT, scanno); // DC and AC together not OK
					}
					else
					{
						if(ncomps!=1) ERREXIT1(cinfo, J_MESSAGE_CODE.JERR_BAD_PROG_SCRIPT, scanno); // AC scans must be for only one component
					}

					for(int ci=0; ci<ncomps; ci++)
					{
						int comp_ind=scan_info.component_index[ci];
						if(Ss!=0&&last_bitpos[comp_ind, 0]<0) ERREXIT1(cinfo, J_MESSAGE_CODE.JERR_BAD_PROG_SCRIPT, scanno); // AC without prior DC scan
						for(int coefi=Ss; coefi<=Se; coefi++)
						{
							if(last_bitpos[comp_ind, coefi]<0)
							{ // first scan of this coefficient
								if(Ah!=0) ERREXIT1(cinfo, J_MESSAGE_CODE.JERR_BAD_PROG_SCRIPT, scanno);
							}
							else
							{ // not first scan
								if(Ah!=last_bitpos[comp_ind, coefi]||Al!=Ah-1) ERREXIT1(cinfo, J_MESSAGE_CODE.JERR_BAD_PROG_SCRIPT, scanno);
							}
							last_bitpos[comp_ind, coefi]=Al;
						}
					}
#endif // C_PROGRESSIVE_SUPPORTED
				}
				else
				{
					// For sequential JPEG, all progression parameters must be these:
					if(Ss!=0||Se!=DCTSIZE2-1||Ah!=0||Al!=0) ERREXIT1(cinfo, J_MESSAGE_CODE.JERR_BAD_PROG_SCRIPT, scanno);

					// Make sure components are not sent twice
					for(int ci=0; ci<ncomps; ci++)
					{
						int thisi=scan_info.component_index[ci];
						if(component_sent[thisi]) ERREXIT1(cinfo, J_MESSAGE_CODE.JERR_BAD_SCAN_SCRIPT, scanno);
						component_sent[thisi]=true;
					}
				}
			} // for(...)

			// Now verify that everything got sent.
			if(cinfo.process==J_CODEC_PROCESS.JPROC_PROGRESSIVE)
			{
#if C_PROGRESSIVE_SUPPORTED
				// For progressive mode, we only check that at least some DC data
				// got sent for each component; the spec does not require that all bits
				// of all coefficients be transmitted. Would it be wiser to enforce
				// transmission of all coefficient bits??
				for(int ci=0; ci<cinfo.num_components; ci++)
				{
					if(last_bitpos[ci, 0]<0) ERREXIT(cinfo, J_MESSAGE_CODE.JERR_MISSING_DATA);
				}
#endif
			}
			else
			{
				for(int ci=0; ci<cinfo.num_components; ci++)
				{
					if(!component_sent[ci]) ERREXIT(cinfo, J_MESSAGE_CODE.JERR_MISSING_DATA);
				}
			}
		}
コード例 #31
0
ファイル: jcmaster.cs プロジェクト: JoshDullen/libjpeg.net
		// Do computations that are needed before processing a JPEG scan
		// cinfo.comps_in_scan and cinfo.cur_comp_info[] are already set
		static void per_scan_setup(jpeg_compress cinfo)
		{
			uint DCT_size=cinfo.DCT_size;

			if(cinfo.comps_in_scan==1)
			{
				// Noninterleaved (single-component) scan
				jpeg_component_info compptr=cinfo.cur_comp_info[0];

				// Overall image size in MCUs
				cinfo.MCUs_per_row=compptr.width_in_blocks;
				cinfo.MCU_rows_in_scan=compptr.height_in_blocks;

				// For noninterleaved scan, always one block per MCU
				compptr.MCU_width=1;
				compptr.MCU_height=1;
				compptr.MCU_blocks=1;
				compptr.MCU_sample_width=(int)DCT_size;
				compptr.last_col_width=1;

				// For noninterleaved scans, it is convenient to define last_row_height
				// as the number of block rows present in the last iMCU row.
				int tmp=(int)(compptr.height_in_blocks%compptr.v_samp_factor);
				if(tmp==0) tmp=compptr.v_samp_factor;
				compptr.last_row_height=tmp;

				// Prepare array describing MCU composition
				cinfo.block_in_MCU=1;
				cinfo.MCU_membership[0]=0;
			}
			else
			{
				// Interleaved (multi-component) scan
				if(cinfo.comps_in_scan<=0||cinfo.comps_in_scan>MAX_COMPS_IN_SCAN)
					ERREXIT2(cinfo, J_MESSAGE_CODE.JERR_COMPONENT_COUNT, cinfo.comps_in_scan, MAX_COMPS_IN_SCAN);

				// Overall image size in MCUs
				cinfo.MCUs_per_row=(uint)jdiv_round_up(cinfo.image_width, cinfo.max_h_samp_factor*DCT_size);
				cinfo.MCU_rows_in_scan=(uint)jdiv_round_up(cinfo.image_height, cinfo.max_v_samp_factor*DCT_size);

				cinfo.block_in_MCU=0;

				for(int ci=0; ci<cinfo.comps_in_scan; ci++)
				{
					jpeg_component_info compptr=cinfo.cur_comp_info[ci];

					// Sampling factors give # of blocks of component in each MCU
					compptr.MCU_width=compptr.h_samp_factor;
					compptr.MCU_height=compptr.v_samp_factor;
					compptr.MCU_blocks=(uint)(compptr.MCU_width*compptr.MCU_height);
					compptr.MCU_sample_width=(int)(compptr.MCU_width*DCT_size);

					// Figure number of non-dummy blocks in last MCU column & row
					int tmp=(int)(compptr.width_in_blocks%compptr.MCU_width);
					if(tmp==0) tmp=compptr.MCU_width;
					compptr.last_col_width=tmp;
					tmp=(int)(compptr.height_in_blocks%compptr.MCU_height);
					if(tmp==0) tmp=compptr.MCU_height;
					compptr.last_row_height=tmp;

					// Prepare array describing MCU composition
					int mcublks=(int)compptr.MCU_blocks;
					if(cinfo.block_in_MCU+mcublks>C_MAX_BLOCKS_IN_MCU) ERREXIT(cinfo, J_MESSAGE_CODE.JERR_BAD_MCU_SIZE);

					while((mcublks--)>0) cinfo.MCU_membership[cinfo.block_in_MCU++]=ci;
				}
			}

			// Convert restart specified in rows to actual MCU count.
			// Note that count must fit in 16 bits, so we provide limiting.
			if(cinfo.restart_in_rows>0) cinfo.restart_interval=(uint)Math.Min(cinfo.restart_in_rows*cinfo.MCUs_per_row, 65535);
		}
コード例 #32
0
ファイル: jcparam.cs プロジェクト: mikel785/libjpeg.net
        // Create a single-entry lossless-JPEG script containing all components.
        // cinfo.num_components must be correct.
        // predictor: 1..7
        // point_transform: 0..data_precision(usally 8) // reduction of colors
        public static void jpeg_simple_lossless(jpeg_compress cinfo, int predictor, int point_transform)
        {
            int ncomps = cinfo.num_components;

            // Safety check to ensure start_compress not called yet.
            if (cinfo.global_state != STATE.CSTART)
            {
                ERREXIT1(cinfo, J_MESSAGE_CODE.JERR_BAD_STATE, cinfo.global_state);
            }

            cinfo.lossless = true;

            // Set jpeg_color_space.
            jpeg_default_colorspace(cinfo);

            // Check to ensure that all components will fit in one scan.
            if (cinfo.num_components > MAX_COMPS_IN_SCAN)
            {
                ERREXIT2(cinfo, J_MESSAGE_CODE.JERR_COMPONENT_COUNT, cinfo.num_components, MAX_COMPS_IN_SCAN);
            }

            // Allocate space for script.
            // We need to put it in the permanent pool in case the application performs
            // multiple compressions without changing the settings. To avoid a memory
            // leak if jpeg_simple_lossless is called repeatedly for the same JPEG
            // object, we try to re-use previously allocated space.
            int nscans = 1;

            if (cinfo.script_space == null || cinfo.script_space_size < nscans)
            {
                cinfo.script_space_size = nscans;

                try
                {
                    cinfo.script_space = new jpeg_scan_info[cinfo.script_space_size];
                    for (int i = 0; i < cinfo.script_space_size; i++)
                    {
                        cinfo.script_space[i] = new jpeg_scan_info();
                    }
                }
                catch
                {
                    ERREXIT1(cinfo, J_MESSAGE_CODE.JERR_OUT_OF_MEMORY, 4);
                }
            }

            jpeg_scan_info scanptr = cinfo.script_space[0];

            cinfo.scan_info = cinfo.script_space;
            cinfo.num_scans = nscans;

            // Fill the script.
            scanptr.comps_in_scan = ncomps;
            for (int ci = 0; ci < ncomps; ci++)
            {
                scanptr.component_index[ci] = ci;
            }
            scanptr.Ss = predictor;
            scanptr.Se = 0;
            scanptr.Ah = 0;
            scanptr.Al = point_transform;
        }
コード例 #33
0
 static void noscale(jpeg_compress cinfo, byte[] input_buf, byte[] output_buf, uint width)
 {
     Array.Copy(input_buf, output_buf, width);
 }
コード例 #34
0
ファイル: jdatadst.cs プロジェクト: JoshDullen/libjpeg.net
		// Terminate destination --- called by jpeg_finish_compress
		// after all data has been written. Usually needs to flush buffer.
		//
		// NB: *not* called by jpeg_abort or jpeg_destroy; surrounding
		// application must deal with any cleanup that should happen even
		// for error exit.
		static void term_destination(jpeg_compress cinfo)
		{
			my_destination_mgr dest=(my_destination_mgr)cinfo.dest;
			int datacount=OUTPUT_BUF_SIZE-(int)dest.free_in_buffer;

			// Write any data remaining in the buffer
			if(datacount>0)
			{
				try
				{
					dest.outfile.Write(dest.buffer, 0, datacount);
				}
				catch
				{
					ERREXIT(cinfo, J_MESSAGE_CODE.JERR_FILE_WRITE);
				}
			}
			dest.outfile.Flush();
		}
コード例 #35
0
ファイル: jcprepct.cs プロジェクト: JoshDullen/libjpeg.net
		// Create the wrapped-around downsampling input buffer needed for context mode.
		static void create_context_buffer(jpeg_compress cinfo)
		{
			my_prep_controller prep=(my_prep_controller)cinfo.prep;
			int rgroup_height=cinfo.max_v_samp_factor;

			for(int ci=0; ci<cinfo.num_components; ci++)
			{
				jpeg_component_info compptr=cinfo.comp_info[ci];

				// Grab enough space for fake row pointers;
				// we need five row groups' worth of pointers for each component.
				byte[][] fake_buffer=new byte[5*rgroup_height][];

				// Allocate the actual buffer space (3 row groups) for this component.
				// We make the buffer wide enough to allow the downsampler to edge-expand
				// horizontally within the buffer, if it so chooses.
				byte[][] true_buffer=alloc_sarray(cinfo,
					(uint)(((int)compptr.width_in_blocks*cinfo.DCT_size*cinfo.max_h_samp_factor)/compptr.h_samp_factor),
					(uint)(3*rgroup_height));

				// Copy true buffer row pointers into the middle of the fake row array
				Array.Copy(true_buffer, 0, fake_buffer, rgroup_height, 3*rgroup_height);

				// Fill in the above and below wraparound pointers
				for(int i=0; i<rgroup_height; i++)
				{
					fake_buffer[i]=true_buffer[2*rgroup_height+i];
					fake_buffer[4*rgroup_height+i]=true_buffer[i];
				}
				prep.color_buf[ci]=fake_buffer;
			}
		}
コード例 #36
0
ファイル: jcsample.cs プロジェクト: JoshDullen/libjpeg.net
		// Do downsampling for a whole row group (all components).
		// In this version we simply downsample each component independently.
		static void sep_downsample(jpeg_compress cinfo, byte[][][] input_buf, uint in_row_index, byte[][][] output_buf, uint out_row_group_index)
		{
			my_downsampler downsample=(my_downsampler)cinfo.downsample;

			for(int ci=0; ci<cinfo.num_components; ci++)
				downsample.methods[ci](cinfo, cinfo.comp_info[ci], input_buf[ci], in_row_index, output_buf[ci], (uint)(out_row_group_index*cinfo.comp_info[ci].v_samp_factor));
		}
コード例 #37
0
ファイル: jcsample.cs プロジェクト: JoshDullen/libjpeg.net
		// Initialize for a downsampling pass.
		static void start_pass_downsample(jpeg_compress cinfo)
		{
			// no work for now
		}
コード例 #38
0
ファイル: jcsample.cs プロジェクト: JoshDullen/libjpeg.net
		// Module initialization routine for downsampling.
		// Note that we must select a routine for each component.
		static void jinit_downsampler(jpeg_compress cinfo)
		{
			my_downsampler downsample=null;

			try
			{
				downsample=new my_downsampler();
			}
			catch
			{
				ERREXIT1(cinfo, J_MESSAGE_CODE.JERR_OUT_OF_MEMORY, 4);
			}

			cinfo.downsample=downsample;
			downsample.start_pass=start_pass_downsample;
			downsample.downsample=sep_downsample;
			downsample.need_context_rows=false;

			if(cinfo.CCIR601_sampling) ERREXIT(cinfo, J_MESSAGE_CODE.JERR_CCIR601_NOTIMPL);

			bool smoothok=true;

			// Verify we can handle the sampling factors, and set up method pointers
			for(int ci=0; ci<cinfo.num_components; ci++)
			{
				jpeg_component_info compptr=cinfo.comp_info[ci];
				if(compptr.h_samp_factor==cinfo.max_h_samp_factor&&compptr.v_samp_factor==cinfo.max_v_samp_factor)
				{
#if INPUT_SMOOTHING_SUPPORTED
					if(cinfo.smoothing_factor!=0)
					{
						downsample.methods[ci]=fullsize_smooth_downsample;
						downsample.need_context_rows=true;
					}
					else
#endif
						downsample.methods[ci]=fullsize_downsample;
				}
				else if(compptr.h_samp_factor*2==cinfo.max_h_samp_factor&&compptr.v_samp_factor==cinfo.max_v_samp_factor)
				{
					smoothok=false;
					downsample.methods[ci]=h2v1_downsample;
				}
				else if(compptr.h_samp_factor*2==cinfo.max_h_samp_factor&&compptr.v_samp_factor*2==cinfo.max_v_samp_factor)
				{
#if INPUT_SMOOTHING_SUPPORTED
					if(cinfo.smoothing_factor!=0)
					{
						downsample.methods[ci]=h2v2_smooth_downsample;
						downsample.need_context_rows=true;
					}
					else
#endif
						downsample.methods[ci]=h2v2_downsample;
				}
				else if((cinfo.max_h_samp_factor%compptr.h_samp_factor)==0&&(cinfo.max_v_samp_factor%compptr.v_samp_factor)==0)
				{
					smoothok=false;
					downsample.methods[ci]=int_downsample;
				}
				else ERREXIT(cinfo, J_MESSAGE_CODE.JERR_FRACT_SAMPLE_NOTIMPL);
			}

#if INPUT_SMOOTHING_SUPPORTED
			if(cinfo.smoothing_factor!=0&&!smoothok) TRACEMS(cinfo, 0, J_MESSAGE_CODE.JTRC_SMOOTH_NOTIMPL);
#endif
		}
コード例 #39
0
        // Expand a Huffman table definition into the derived format
        // Compute the derived values for a Huffman table.
        // This routine also performs some validation checks on the table.
        static void jpeg_make_c_derived_tbl(jpeg_compress cinfo, bool isDC, int tblno, ref c_derived_tbl pdtbl)
        {
            // Note that huffsize[] and huffcode[] are filled in code-length order,
            // paralleling the order of the symbols themselves in htbl.huffval[].

            // Find the input Huffman table
            if (tblno < 0 || tblno >= NUM_HUFF_TBLS)
            {
                ERREXIT1(cinfo, J_MESSAGE_CODE.JERR_NO_HUFF_TABLE, tblno);
            }
            JHUFF_TBL htbl = isDC?cinfo.dc_huff_tbl_ptrs[tblno]:cinfo.ac_huff_tbl_ptrs[tblno];

            if (htbl == null)
            {
                ERREXIT1(cinfo, J_MESSAGE_CODE.JERR_NO_HUFF_TABLE, tblno);
            }

            // Allocate a workspace if we haven't already done so.
            if (pdtbl == null)
            {
                try
                {
                    pdtbl = new c_derived_tbl();
                }
                catch
                {
                    ERREXIT1(cinfo, J_MESSAGE_CODE.JERR_OUT_OF_MEMORY, 4);
                }
            }

            c_derived_tbl dtbl = pdtbl;

            // Figure C.1: make table of Huffman code length for each symbol
            byte[] huffsize = new byte[257];
            int    p        = 0;

            for (byte l = 1; l <= 16; l++)
            {
                int i = htbl.bits[l];
                // protect against table overrun
                if (i < 0 || (p + i) > 256)
                {
                    ERREXIT(cinfo, J_MESSAGE_CODE.JERR_BAD_HUFF_TABLE);
                }
                while ((i--) != 0)
                {
                    huffsize[p++] = l;
                }
            }
            huffsize[p] = 0;
            int lastp = p;

            // Figure C.2: generate the codes themselves
            // We also validate that the counts represent a legal Huffman code tree.
            uint[] huffcode = new uint[257];
            uint   code     = 0;
            int    si       = huffsize[0];

            p = 0;
            while (huffsize[p] != 0)
            {
                while (((int)huffsize[p]) == si)
                {
                    huffcode[p++] = code;
                    code++;
                }
                // code is now 1 more than the last code used for codelength si; but
                // it must still fit in si bits, since no code is allowed to be all ones.
                if (((int)code) >= (1 << si))
                {
                    ERREXIT(cinfo, J_MESSAGE_CODE.JERR_BAD_HUFF_TABLE);
                }
                code <<= 1;
                si++;
            }

            // Figure C.3: generate encoding tables
            // These are code and size indexed by symbol value

            // Set all codeless symbols to have code length 0;
            // this lets us detect duplicate VAL entries here, and later
            // allows emit_bits to detect any attempt to emit such symbols.
            for (int i = 0; i < 256; i++)
            {
                dtbl.ehufsi[i] = 0;
            }

            // This is also a convenient place to check for out-of-range
            // and duplicated VAL entries. We allow 0..255 for AC symbols
            // but only 0..16 for DC. (We could constrain them further
            // based on data depth and mode, but this seems enough.)
            int maxsymbol = isDC?16:255;

            for (p = 0; p < lastp; p++)
            {
                int i = htbl.huffval[p];
                if (i < 0 || i > maxsymbol || dtbl.ehufsi[i] != 0)
                {
                    ERREXIT(cinfo, J_MESSAGE_CODE.JERR_BAD_HUFF_TABLE);
                }
                dtbl.ehufco[i] = huffcode[p];
                dtbl.ehufsi[i] = huffsize[p];
            }
        }
コード例 #40
0
        // Generate an optimal table definition given the specified counts
        // Generate the best Huffman code table for the given counts, fill htbl.

        // The JPEG standard requires that no symbol be assigned a codeword of all
        // one bits (so that padding bits added at the end of a compressed segment
        // can't look like a valid code). Because of the canonical ordering of
        // codewords, this just means that there must be an unused slot in the
        // longest codeword length category. Section K.2 of the JPEG spec suggests
        // reserving such a slot by pretending that symbol 256 is a valid symbol
        // with count 1. In theory that's not optimal; giving it count zero but
        // including it in the symbol set anyway should give a better Huffman code.
        // But the theoretically better code actually seems to come out worse in
        // practice, because it produces more all-ones bytes (which incur stuffed
        // zero bytes in the final file). In any case the difference is tiny.

        // The JPEG standard requires Huffman codes to be no more than 16 bits long.
        // If some symbols have a very small but nonzero probability, the Huffman tree
        // must be adjusted to meet the code length restriction. We currently use
        // the adjustment method suggested in JPEG section K.2. This method is *not*
        // optimal; it may not choose the best possible limited-length code. But
        // typically only very-low-frequency symbols will be given less-than-optimal
        // lengths, so the code is almost optimal. Experimental comparisons against
        // an optimal limited-length-code algorithm indicate that the difference is
        // microscopic --- usually less than a hundredth of a percent of total size.
        // So the extra complexity of an optimal algorithm doesn't seem worthwhile.
        static void jpeg_gen_optimal_table(jpeg_compress cinfo, JHUFF_TBL htbl, int[] freq)
        {
            int MAX_CLEN = 32;                                  // assumed maximum initial code length

            byte[] bits     = new byte[MAX_CLEN + 1];           // bits[k] = # of symbols with code length k
            int[]  codesize = new int[257];                     // codesize[k] = code length of symbol k
            int[]  others   = new int[257];                     // next symbol in current branch of tree

            // This algorithm is explained in section K.2 of the JPEG standard
            for (int i = 0; i < 257; i++)
            {
                others[i] = -1;                                 // init links to empty
            }
            freq[256] = 1;                                      // make sure 256 has a nonzero count
            // Including the pseudo-symbol 256 in the Huffman procedure guarantees
            // that no real symbol is given code-value of all ones, because 256
            // will be placed last in the largest codeword category.

            // Huffman's basic algorithm to assign optimal code lengths to symbols

            for (; ;)
            {
                // Find the smallest nonzero frequency, set c1 = its symbol
                // In case of ties, take the larger symbol number
                int c1 = -1;
                int v  = 1000000000;
                for (int i = 0; i <= 256; i++)
                {
                    if (freq[i] != 0 && freq[i] <= v)
                    {
                        v  = freq[i];
                        c1 = i;
                    }
                }

                // Find the next smallest nonzero frequency, set c2 = its symbol
                // In case of ties, take the larger symbol number
                int c2 = -1;
                v = 1000000000;
                for (int i = 0; i <= 256; i++)
                {
                    if (freq[i] != 0 && freq[i] <= v && i != c1)
                    {
                        v  = freq[i];
                        c2 = i;
                    }
                }

                // Done if we've merged everything into one frequency
                if (c2 < 0)
                {
                    break;
                }

                // Else merge the two counts/trees
                freq[c1] += freq[c2];
                freq[c2]  = 0;

                // Increment the codesize of everything in c1's tree branch
                codesize[c1]++;
                while (others[c1] >= 0)
                {
                    c1 = others[c1];
                    codesize[c1]++;
                }

                others[c1] = c2;                        // chain c2 onto c1's tree branch

                // Increment the codesize of everything in c2's tree branch
                codesize[c2]++;
                while (others[c2] >= 0)
                {
                    c2 = others[c2];
                    codesize[c2]++;
                }
            }

            // Now count the number of symbols of each code length
            for (int i = 0; i <= 256; i++)
            {
                if (codesize[i] != 0)
                {
                    // The JPEG standard seems to think that this can't happen,
                    // but I'm paranoid...
                    if (codesize[i] > MAX_CLEN)
                    {
                        ERREXIT(cinfo, J_MESSAGE_CODE.JERR_HUFF_CLEN_OVERFLOW);
                    }

                    bits[codesize[i]]++;
                }
            }

            // JPEG doesn't allow symbols with code lengths over 16 bits, so if the pure
            // Huffman procedure assigned any such lengths, we must adjust the coding.
            // Here is what the JPEG spec says about how this next bit works:
            // Since symbols are paired for the longest Huffman code, the symbols are
            // removed from this length category two at a time. The prefix for the pair
            // (which is one bit shorter) is allocated to one of the pair; then,
            // skipping the BITS entry for that prefix length, a code word from the next
            // shortest nonzero BITS entry is converted into a prefix for two code words
            // one bit longer.
            int k;

            for (k = MAX_CLEN; k > 16; k--)
            {
                while (bits[k] > 0)
                {
                    int j = k - 2;                              // find length of new prefix to be used
                    while (bits[j] == 0)
                    {
                        j--;
                    }

                    bits[k] -= 2;                       // remove two symbols
                    bits[k - 1]++;                      // one goes in this length
                    bits[j + 1] += 2;                   // two new symbols in this length
                    bits[j]--;                          // symbol of this length is now a prefix
                }
            }

            // Remove the count for the pseudo-symbol 256 from the largest codelength
            while (bits[k] == 0)
            {
                k--;                            // find largest codelength still in use
            }
            bits[k]--;

            // Return final symbol counts (only for lengths 0..16)
            Array.Copy(bits, htbl.bits, 17);

            // Return a list of the symbols sorted by code length
            // It's not real clear to me why we don't need to consider the codelength
            // changes made above, but the JPEG spec seems to think this works.
            for (int i = 1, p = 0; i <= MAX_CLEN; i++)
            {
                for (int j = 0; j <= 255; j++)
                {
                    if (codesize[j] == i)
                    {
                        htbl.huffval[p] = (byte)j;
                        p++;
                    }
                }
            }

            // Set sent_table false so updated table will be written to JPEG file.
            htbl.sent_table = false;
        }
コード例 #41
0
ファイル: jcprepct.cs プロジェクト: JoshDullen/libjpeg.net
		// Process some data in the context case.
		static void pre_process_context(jpeg_compress cinfo, byte[][] input_buf, ref uint in_row_ctr, uint in_rows_avail, byte[][][] output_buf, ref uint out_row_group_ctr, uint out_row_groups_avail)
		{
			my_prep_controller prep=(my_prep_controller)cinfo.prep;
			int buf_height=cinfo.max_v_samp_factor*3;
			int rgroup_height=cinfo.max_v_samp_factor;

			while(out_row_group_ctr<out_row_groups_avail)
			{
				if(in_row_ctr<in_rows_avail)
				{
					// Do color conversion to fill the conversion buffer.
					uint inrows=in_rows_avail-in_row_ctr;
					int numrows=prep.next_buf_stop-prep.next_buf_row;
					numrows=(int)Math.Min((uint)numrows, inrows);
					cinfo.cconvert.color_convert(cinfo, input_buf, in_row_ctr, prep.color_buf, (uint)rgroup_height+(uint)prep.next_buf_row, numrows);

					// Pad at top of image, if first time through
					if(prep.rows_to_go==cinfo.image_height)
					{
						for(int ci=0; ci<cinfo.num_components; ci++)
							for(int row=1; row<=cinfo.max_v_samp_factor; row++)
								jcopy_sample_rows(prep.color_buf[ci], rgroup_height, prep.color_buf[ci], rgroup_height-row, 1, cinfo.image_width);
					}
					in_row_ctr+=(uint)numrows;
					prep.next_buf_row+=numrows;
					prep.rows_to_go-=(uint)numrows;
				}
				else
				{
					// Return for more data, unless we are at the bottom of the image.
					if(prep.rows_to_go!=0) break;

					// When at bottom of image, pad to fill the conversion buffer.
					if(prep.next_buf_row<prep.next_buf_stop)
					{
						for(int ci=0; ci<cinfo.num_components; ci++)
							expand_bottom_edge(prep.color_buf[ci], cinfo.image_width, rgroup_height+prep.next_buf_row, rgroup_height+prep.next_buf_stop);

						prep.next_buf_row=prep.next_buf_stop;
					}
				}

				// If we've gotten enough data, downsample a row group.
				if(prep.next_buf_row==prep.next_buf_stop)
				{
					cinfo.downsample.downsample(cinfo, prep.color_buf, (uint)rgroup_height+(uint)prep.this_row_group, output_buf, out_row_group_ctr);
					out_row_group_ctr++;

					// Advance pointers with wraparound as necessary.
					prep.this_row_group+=cinfo.max_v_samp_factor;
					if(prep.this_row_group>=buf_height) prep.this_row_group=0;
					if(prep.next_buf_row>=buf_height) prep.next_buf_row=0;
					prep.next_buf_stop=prep.next_buf_row+cinfo.max_v_samp_factor;
				}
			} // while(...)
		}
コード例 #42
0
ファイル: jcapistd.cs プロジェクト: JoshDullen/libjpeg.net
		public static uint jpeg_write_image(jpeg_compress cinfo, byte[] image, bool swapChannels, bool alpha)
		{
			if(cinfo.input_components!=3||cinfo.lossless||cinfo.in_color_space!=J_COLOR_SPACE.JCS_RGB||
				cinfo.num_components!=3||cinfo.jpeg_color_space!=J_COLOR_SPACE.JCS_YCbCr||
				cinfo.data_precision!=8||cinfo.DCT_size!=8||cinfo.block_in_MCU!=3||cinfo.arith_code||
				cinfo.max_h_samp_factor!=1||cinfo.max_v_samp_factor!=1||cinfo.next_scanline!=0||cinfo.num_scans!=1)
			{
				throw new Exception();
			}

			if(cinfo.global_state!=STATE.CSCANNING) ERREXIT1(cinfo, J_MESSAGE_CODE.JERR_BAD_STATE, cinfo.global_state);

			// Give master control module another chance if this is first call to
			// jpeg_write_scanlines. This lets output of the frame/scan headers be
			// delayed so that application can write COM, etc, markers between
			// jpeg_start_compress and jpeg_write_scanlines.
			if(cinfo.master.call_pass_startup) cinfo.master.pass_startup(cinfo);

			jpeg_lossy_c_codec lossyc=(jpeg_lossy_c_codec)cinfo.coef;
			c_coef_controller coef=(c_coef_controller)lossyc.coef_private;
			fdct_controller fdct=(fdct_controller)lossyc.fdct_private;

			double[] workspaceY=new double[DCTSIZE2];
			double[] workspaceCr=new double[DCTSIZE2];
			double[] workspaceCb=new double[DCTSIZE2];

			short[][] coefs=new short[][] { new short[DCTSIZE2], new short[DCTSIZE2], new short[DCTSIZE2] };

			short[] coefY=coefs[0];
			short[] coefCb=coefs[1];
			short[] coefCr=coefs[2];

			double[] divisorY=fdct.float_divisors[0];
			double[] divisorC=fdct.float_divisors[1];

			int bpp=alpha?4:3;

			for(int y=0; y<(cinfo.image_height+DCTSIZE-1)/DCTSIZE; y++)
			{
				int yFormImage=Math.Min((int)cinfo.image_height-y*DCTSIZE, DCTSIZE);
				for(int x=0; x<(cinfo.image_width+DCTSIZE-1)/DCTSIZE; x++)
				{
					int xFormImage=Math.Min((int)cinfo.image_width-x*DCTSIZE, DCTSIZE);
					int workspacepos=0;
					for(int j=0; j<yFormImage; j++)
					{
						int imagepos=((y*DCTSIZE+j)*(int)cinfo.image_width+x*DCTSIZE)*bpp;
						for(int i=0; i<xFormImage; i++, workspacepos++)
						{
							byte r=image[imagepos++];
							byte g=image[imagepos++];
							byte b=image[imagepos++];
							if(alpha) imagepos++;

							if(!swapChannels)
							{
								workspaceY[workspacepos]=0.299*r+0.587*g+0.114*b-CENTERJSAMPLE;
								workspaceCb[workspacepos]=-0.168736*r-0.331264*g+0.5*b;
								workspaceCr[workspacepos]=0.5*r-0.418688*g-0.081312*b;
							}
							else
							{
								workspaceY[workspacepos]=0.299*b+0.587*g+0.114*r-CENTERJSAMPLE;
								workspaceCb[workspacepos]=-0.168736*b-0.331264*g+0.5*r;
								workspaceCr[workspacepos]=0.5*b-0.418688*g-0.081312*r;
							}
						}

						int lastworkspacepos=workspacepos-1;
						for(int i=xFormImage; i<DCTSIZE; i++, workspacepos++)
						{
							workspaceY[workspacepos]=workspaceY[lastworkspacepos];
							workspaceCb[workspacepos]=workspaceCb[lastworkspacepos];
							workspaceCr[workspacepos]=workspaceCr[lastworkspacepos];
						}
					}

					int lastworkspacelinepos=(yFormImage-1)*DCTSIZE;
					for(int j=yFormImage; j<DCTSIZE; j++)
					{
						int lastworkspacepos=lastworkspacelinepos;
						for(int i=0; i<DCTSIZE; i++, workspacepos++, lastworkspacepos++)
						{
							workspaceY[workspacepos]=workspaceY[lastworkspacepos];
							workspaceCb[workspacepos]=workspaceCb[lastworkspacepos];
							workspaceCr[workspacepos]=workspaceCr[lastworkspacepos];
						}
					}

					// ein block (3 componenten)
					jpeg_fdct_float(workspaceY);
					jpeg_fdct_float(workspaceCb);
					jpeg_fdct_float(workspaceCr);

					for(int i=0; i<DCTSIZE2; i++)
					{
						// Apply the quantization and scaling factor
						double tempY=workspaceY[i]*divisorY[i];
						double tempCb=workspaceCb[i]*divisorC[i];
						double tempCr=workspaceCr[i]*divisorC[i];

						// Round to nearest integer.
						// Since C does not specify the direction of rounding for negative
						// quotients, we have to force the dividend positive for portability.
						// The maximum coefficient size is +-16K (for 12-bit data), so this
						// code should work for either 16-bit or 32-bit ints.
						coefY[i]=(short)((int)(tempY+16384.5)-16384);
						coefCb[i]=(short)((int)(tempCb+16384.5)-16384);
						coefCr[i]=(short)((int)(tempCr+16384.5)-16384);
					}

					lossyc.entropy_encode_mcu(cinfo, coefs);
				}
			}

			cinfo.next_scanline=cinfo.image_height;
			return cinfo.image_height;
		}
コード例 #43
0
ファイル: jcprepct.cs プロジェクト: JoshDullen/libjpeg.net
		// Initialize preprocessing controller.
		static void jinit_c_prep_controller(jpeg_compress cinfo, bool need_full_buffer)
		{
			if(need_full_buffer) ERREXIT(cinfo, J_MESSAGE_CODE.JERR_BAD_BUFFER_MODE); // safety check

			my_prep_controller prep=null;

			try
			{
				prep=new my_prep_controller();
			}
			catch
			{
				ERREXIT1(cinfo, J_MESSAGE_CODE.JERR_OUT_OF_MEMORY, 4);
			}
			cinfo.prep=prep;
			prep.start_pass=start_pass_prep;

			// Allocate the color conversion buffer.
			// We make the buffer wide enough to allow the downsampler to edge-expand
			// horizontally within the buffer, if it so chooses.
			if(cinfo.downsample.need_context_rows)
			{
				// Set up to provide context rows
#if CONTEXT_ROWS_SUPPORTED
				prep.pre_process_data=pre_process_context;
				create_context_buffer(cinfo);
#else
				ERREXIT(cinfo, J_MESSAGE_CODE.JERR_NOT_COMPILED);
#endif
			}
			else
			{
				// No context, just make it tall enough for one row group
				prep.pre_process_data=pre_process_data;
				for(int ci=0; ci<cinfo.num_components; ci++)
				{
					jpeg_component_info compptr=cinfo.comp_info[ci];
					prep.color_buf[ci]=alloc_sarray(cinfo,
						(uint)(((int)compptr.width_in_blocks*cinfo.DCT_size*cinfo.max_h_samp_factor)/compptr.h_samp_factor),
						(uint)cinfo.max_v_samp_factor);
				}
			}
		}
コード例 #44
0
ファイル: jcparam.cs プロジェクト: mikel785/libjpeg.net
 // Set the JPEG colorspace, and choose colorspace-dependent default values.
 public static void jpeg_set_colorspace(jpeg_compress cinfo, J_COLOR_SPACE colorspace)
 {
     jpeg_set_colorspace(cinfo, colorspace, J_SUBSAMPLING.JPEG420);
 }
コード例 #45
0
ファイル: jcprepct.cs プロジェクト: JoshDullen/libjpeg.net
		// Process some data in the simple no-context case.
		//
		// Preprocessor output data is counted in "row groups". A row group
		// is defined to be v_samp_factor sample rows of each component.
		// Downsampling will produce this much data from each max_v_samp_factor input rows.
		static void pre_process_data(jpeg_compress cinfo, byte[][] input_buf, ref uint in_row_ctr, uint in_rows_avail, byte[][][] output_buf, ref uint out_row_group_ctr, uint out_row_groups_avail)
		{
			my_prep_controller prep=(my_prep_controller)cinfo.prep;
				
			while(in_row_ctr<in_rows_avail&&out_row_group_ctr<out_row_groups_avail)
			{
				// Do color conversion to fill the conversion buffer.
				uint inrows=in_rows_avail-in_row_ctr;
				int numrows=cinfo.max_v_samp_factor-prep.next_buf_row;
				numrows=(int)Math.Min((uint)numrows, inrows);
				cinfo.cconvert.color_convert(cinfo, input_buf, in_row_ctr, prep.color_buf, (uint)prep.next_buf_row, numrows);
				in_row_ctr+=(uint)numrows;
				prep.next_buf_row+=numrows;
				prep.rows_to_go-=(uint)numrows;
				// If at bottom of image, pad to fill the conversion buffer.
				if(prep.rows_to_go==0&&prep.next_buf_row<cinfo.max_v_samp_factor)
				{
					for(int ci=0; ci<cinfo.num_components; ci++) expand_bottom_edge(prep.color_buf[ci], cinfo.image_width, prep.next_buf_row, cinfo.max_v_samp_factor);
					prep.next_buf_row=cinfo.max_v_samp_factor;
				}
				// If we've filled the conversion buffer, empty it.
				if(prep.next_buf_row==cinfo.max_v_samp_factor)
				{
					cinfo.downsample.downsample(cinfo, prep.color_buf, 0, output_buf, out_row_group_ctr);
					prep.next_buf_row=0;
					out_row_group_ctr++;
				}
				// If at bottom of image, pad the output to a full iMCU height.
				// Note we assume the caller is providing a one-iMCU-height output buffer!
				if(prep.rows_to_go==0&&out_row_group_ctr<out_row_groups_avail)
				{
					for(int ci=0; ci<cinfo.num_components; ci++)
					{
						jpeg_component_info compptr=cinfo.comp_info[ci];
						expand_bottom_edge(output_buf[ci], compptr.width_in_blocks*cinfo.DCT_size, (int)(out_row_group_ctr*compptr.v_samp_factor), (int)(out_row_groups_avail*compptr.v_samp_factor));
					}
					out_row_group_ctr=out_row_groups_avail;
					break;			// can exit outer loop without test
				}
			} // while(...)
		}
コード例 #46
0
        public static uint jpeg_write_image(jpeg_compress cinfo, byte[] image, bool swapChannels, bool alpha)
        {
            if (cinfo.input_components != 3 || cinfo.lossless || cinfo.in_color_space != J_COLOR_SPACE.JCS_RGB ||
                cinfo.num_components != 3 || cinfo.jpeg_color_space != J_COLOR_SPACE.JCS_YCbCr ||
                cinfo.data_precision != 8 || cinfo.DCT_size != 8 || cinfo.block_in_MCU != 3 || cinfo.arith_code ||
                cinfo.max_h_samp_factor != 1 || cinfo.max_v_samp_factor != 1 || cinfo.next_scanline != 0 || cinfo.num_scans != 1)
            {
                throw new Exception();
            }

            if (cinfo.global_state != STATE.CSCANNING)
            {
                ERREXIT1(cinfo, J_MESSAGE_CODE.JERR_BAD_STATE, cinfo.global_state);
            }

            // Give master control module another chance if this is first call to
            // jpeg_write_scanlines. This lets output of the frame/scan headers be
            // delayed so that application can write COM, etc, markers between
            // jpeg_start_compress and jpeg_write_scanlines.
            if (cinfo.master.call_pass_startup)
            {
                cinfo.master.pass_startup(cinfo);
            }

            jpeg_lossy_c_codec lossyc = (jpeg_lossy_c_codec)cinfo.coef;
            c_coef_controller  coef   = (c_coef_controller)lossyc.coef_private;
            fdct_controller    fdct   = (fdct_controller)lossyc.fdct_private;

            double[] workspaceY  = new double[DCTSIZE2];
            double[] workspaceCr = new double[DCTSIZE2];
            double[] workspaceCb = new double[DCTSIZE2];

            short[][] coefs = new short[][] { new short[DCTSIZE2], new short[DCTSIZE2], new short[DCTSIZE2] };

            short[] coefY  = coefs[0];
            short[] coefCb = coefs[1];
            short[] coefCr = coefs[2];

            double[] divisorY = fdct.float_divisors[0];
            double[] divisorC = fdct.float_divisors[1];

            int bpp = alpha?4:3;

            for (int y = 0; y < (cinfo.image_height + DCTSIZE - 1) / DCTSIZE; y++)
            {
                int yFormImage = Math.Min((int)cinfo.image_height - y * DCTSIZE, DCTSIZE);
                for (int x = 0; x < (cinfo.image_width + DCTSIZE - 1) / DCTSIZE; x++)
                {
                    int xFormImage   = Math.Min((int)cinfo.image_width - x * DCTSIZE, DCTSIZE);
                    int workspacepos = 0;
                    for (int j = 0; j < yFormImage; j++)
                    {
                        int imagepos = ((y * DCTSIZE + j) * (int)cinfo.image_width + x * DCTSIZE) * bpp;
                        for (int i = 0; i < xFormImage; i++, workspacepos++)
                        {
                            byte r = image[imagepos++];
                            byte g = image[imagepos++];
                            byte b = image[imagepos++];
                            if (alpha)
                            {
                                imagepos++;
                            }

                            if (!swapChannels)
                            {
                                workspaceY[workspacepos]  = 0.299 * r + 0.587 * g + 0.114 * b - CENTERJSAMPLE;
                                workspaceCb[workspacepos] = -0.168736 * r - 0.331264 * g + 0.5 * b;
                                workspaceCr[workspacepos] = 0.5 * r - 0.418688 * g - 0.081312 * b;
                            }
                            else
                            {
                                workspaceY[workspacepos]  = 0.299 * b + 0.587 * g + 0.114 * r - CENTERJSAMPLE;
                                workspaceCb[workspacepos] = -0.168736 * b - 0.331264 * g + 0.5 * r;
                                workspaceCr[workspacepos] = 0.5 * b - 0.418688 * g - 0.081312 * r;
                            }
                        }

                        int lastworkspacepos = workspacepos - 1;
                        for (int i = xFormImage; i < DCTSIZE; i++, workspacepos++)
                        {
                            workspaceY[workspacepos]  = workspaceY[lastworkspacepos];
                            workspaceCb[workspacepos] = workspaceCb[lastworkspacepos];
                            workspaceCr[workspacepos] = workspaceCr[lastworkspacepos];
                        }
                    }

                    int lastworkspacelinepos = (yFormImage - 1) * DCTSIZE;
                    for (int j = yFormImage; j < DCTSIZE; j++)
                    {
                        int lastworkspacepos = lastworkspacelinepos;
                        for (int i = 0; i < DCTSIZE; i++, workspacepos++, lastworkspacepos++)
                        {
                            workspaceY[workspacepos]  = workspaceY[lastworkspacepos];
                            workspaceCb[workspacepos] = workspaceCb[lastworkspacepos];
                            workspaceCr[workspacepos] = workspaceCr[lastworkspacepos];
                        }
                    }

                    // ein block (3 componenten)
                    jpeg_fdct_float(workspaceY);
                    jpeg_fdct_float(workspaceCb);
                    jpeg_fdct_float(workspaceCr);

                    for (int i = 0; i < DCTSIZE2; i++)
                    {
                        // Apply the quantization and scaling factor
                        double tempY  = workspaceY[i] * divisorY[i];
                        double tempCb = workspaceCb[i] * divisorC[i];
                        double tempCr = workspaceCr[i] * divisorC[i];

                        // Round to nearest integer.
                        // Since C does not specify the direction of rounding for negative
                        // quotients, we have to force the dividend positive for portability.
                        // The maximum coefficient size is +-16K (for 12-bit data), so this
                        // code should work for either 16-bit or 32-bit ints.
                        coefY[i]  = (short)((int)(tempY + 16384.5) - 16384);
                        coefCb[i] = (short)((int)(tempCb + 16384.5) - 16384);
                        coefCr[i] = (short)((int)(tempCr + 16384.5) - 16384);
                    }

                    lossyc.entropy_encode_mcu(cinfo, coefs);
                }
            }

            cinfo.next_scanline = cinfo.image_height;
            return(cinfo.image_height);
        }
コード例 #47
0
ファイル: jchuff.cs プロジェクト: JoshDullen/libjpeg.net
		// Generate an optimal table definition given the specified counts
		// Generate the best Huffman code table for the given counts, fill htbl.

		// The JPEG standard requires that no symbol be assigned a codeword of all
		// one bits (so that padding bits added at the end of a compressed segment
		// can't look like a valid code). Because of the canonical ordering of
		// codewords, this just means that there must be an unused slot in the
		// longest codeword length category. Section K.2 of the JPEG spec suggests
		// reserving such a slot by pretending that symbol 256 is a valid symbol
		// with count 1. In theory that's not optimal; giving it count zero but
		// including it in the symbol set anyway should give a better Huffman code.
		// But the theoretically better code actually seems to come out worse in
		// practice, because it produces more all-ones bytes (which incur stuffed
		// zero bytes in the final file). In any case the difference is tiny.

		// The JPEG standard requires Huffman codes to be no more than 16 bits long.
		// If some symbols have a very small but nonzero probability, the Huffman tree
		// must be adjusted to meet the code length restriction. We currently use
		// the adjustment method suggested in JPEG section K.2. This method is *not*
		// optimal; it may not choose the best possible limited-length code. But
		// typically only very-low-frequency symbols will be given less-than-optimal
		// lengths, so the code is almost optimal. Experimental comparisons against
		// an optimal limited-length-code algorithm indicate that the difference is
		// microscopic --- usually less than a hundredth of a percent of total size.
		// So the extra complexity of an optimal algorithm doesn't seem worthwhile.
		static void jpeg_gen_optimal_table(jpeg_compress cinfo, JHUFF_TBL htbl, int[] freq)
		{
			int MAX_CLEN=32;					// assumed maximum initial code length
			byte[] bits=new byte[MAX_CLEN+1];	// bits[k] = # of symbols with code length k
			int[] codesize=new int[257];		// codesize[k] = code length of symbol k
			int[] others=new int[257];			// next symbol in current branch of tree

			// This algorithm is explained in section K.2 of the JPEG standard
			for(int i=0; i<257; i++) others[i]=-1;	// init links to empty

			freq[256]=1;						// make sure 256 has a nonzero count
			// Including the pseudo-symbol 256 in the Huffman procedure guarantees
			// that no real symbol is given code-value of all ones, because 256
			// will be placed last in the largest codeword category.

			// Huffman's basic algorithm to assign optimal code lengths to symbols

			for(; ; )
			{
				// Find the smallest nonzero frequency, set c1 = its symbol
				// In case of ties, take the larger symbol number
				int c1=-1;
				int v=1000000000;
				for(int i=0; i<=256; i++)
				{
					if(freq[i]!=0&&freq[i]<=v)
					{
						v=freq[i];
						c1=i;
					}
				}

				// Find the next smallest nonzero frequency, set c2 = its symbol
				// In case of ties, take the larger symbol number
				int c2=-1;
				v=1000000000;
				for(int i=0; i<=256; i++)
				{
					if(freq[i]!=0&&freq[i]<=v&&i!=c1)
					{
						v=freq[i];
						c2=i;
					}
				}

				// Done if we've merged everything into one frequency
				if(c2<0) break;

				// Else merge the two counts/trees
				freq[c1]+=freq[c2];
				freq[c2]=0;

				// Increment the codesize of everything in c1's tree branch
				codesize[c1]++;
				while(others[c1]>=0)
				{
					c1=others[c1];
					codesize[c1]++;
				}

				others[c1]=c2;		// chain c2 onto c1's tree branch

				// Increment the codesize of everything in c2's tree branch
				codesize[c2]++;
				while(others[c2]>=0)
				{
					c2=others[c2];
					codesize[c2]++;
				}
			}

			// Now count the number of symbols of each code length
			for(int i=0; i<=256; i++)
			{
				if(codesize[i]!=0)
				{
					// The JPEG standard seems to think that this can't happen,
					// but I'm paranoid...
					if(codesize[i]>MAX_CLEN) ERREXIT(cinfo, J_MESSAGE_CODE.JERR_HUFF_CLEN_OVERFLOW);

					bits[codesize[i]]++;
				}
			}

			// JPEG doesn't allow symbols with code lengths over 16 bits, so if the pure
			// Huffman procedure assigned any such lengths, we must adjust the coding.
			// Here is what the JPEG spec says about how this next bit works:
			// Since symbols are paired for the longest Huffman code, the symbols are
			// removed from this length category two at a time. The prefix for the pair
			// (which is one bit shorter) is allocated to one of the pair; then,
			// skipping the BITS entry for that prefix length, a code word from the next
			// shortest nonzero BITS entry is converted into a prefix for two code words
			// one bit longer.
			int k;
			for(k=MAX_CLEN; k>16; k--)
			{
				while(bits[k]>0)
				{
					int j=k-2;		// find length of new prefix to be used
					while(bits[j]==0) j--;

					bits[k]-=2;		// remove two symbols
					bits[k-1]++;	// one goes in this length
					bits[j+1]+=2;	// two new symbols in this length
					bits[j]--;		// symbol of this length is now a prefix
				}
			}

			// Remove the count for the pseudo-symbol 256 from the largest codelength
			while(bits[k]==0) k--;	// find largest codelength still in use
			bits[k]--;

			// Return final symbol counts (only for lengths 0..16)
			Array.Copy(bits, htbl.bits, 17);

			// Return a list of the symbols sorted by code length
			// It's not real clear to me why we don't need to consider the codelength
			// changes made above, but the JPEG spec seems to think this works.
			for(int i=1, p=0; i<=MAX_CLEN; i++)
			{
				for(int j=0; j<=255; j++)
				{
					if(codesize[j]==i)
					{
						htbl.huffval[p]=(byte)j;
						p++;
					}
				}
			}

			// Set sent_table false so updated table will be written to JPEG file.
			htbl.sent_table=false;
		}
コード例 #48
0
        // Special version of compress_data_diff with input_buf offsets.
        static bool compress_data_diff(jpeg_compress cinfo, byte[][][] input_buf, int[] input_buf_ind)
        {
            jpeg_lossless_c_codec losslsc = (jpeg_lossless_c_codec)cinfo.coef;
            c_diff_controller     diff    = (c_diff_controller)losslsc.diff_private;

            uint last_MCU_col  = cinfo.MCUs_per_row - 1;
            uint last_iMCU_row = cinfo.total_iMCU_rows - 1;

            // Loop to write as much as one whole iMCU row
            for (int yoffset = diff.MCU_vert_offset; yoffset < diff.MCU_rows_per_iMCU_row; yoffset++)
            {
                uint MCU_col_num = diff.mcu_ctr;               // index of current MCU within row

                // Scale and predict each scanline of the MCU-row separately.
                //
                // Note: We only do this if we are at the start of a MCU-row, ie,
                // we don't want to reprocess a row suspended by the output.
                if (MCU_col_num == 0)
                {
                    for (int comp = 0; comp < cinfo.comps_in_scan; comp++)
                    {
                        jpeg_component_info compptr = cinfo.cur_comp_info[comp];
                        int ci = compptr.component_index;
                        int samp_rows;
                        if (diff.iMCU_row_num < last_iMCU_row)
                        {
                            samp_rows = compptr.v_samp_factor;
                        }
                        else
                        {
                            // NB: can't use last_row_height here, since may not be set!
                            samp_rows = (int)(compptr.height_in_blocks % compptr.v_samp_factor);
                            if (samp_rows == 0)
                            {
                                samp_rows = compptr.v_samp_factor;
                            }
                            else
                            {
                                // Fill dummy difference rows at the bottom edge with zeros, which
                                // will encode to the smallest amount of data.
                                for (int samp_row = samp_rows; samp_row < compptr.v_samp_factor; samp_row++)
                                {
                                    int c = jround_up((int)compptr.width_in_blocks, (int)compptr.h_samp_factor);
                                    for (int i = 0; i < c; i++)
                                    {
                                        diff.diff_buf[ci][samp_row][i] = 0;
                                    }
                                }
                            }
                        }

                        uint samps_across = compptr.width_in_blocks;
                        for (int samp_row = 0; samp_row < samp_rows; samp_row++)
                        {
                            losslsc.scaler_scale(cinfo, input_buf[ci][input_buf_ind[ci] + samp_row], diff.cur_row[ci], samps_across);
                            losslsc.predict_difference[ci](cinfo, ci, diff.cur_row[ci], diff.prev_row[ci], diff.diff_buf[ci][samp_row], samps_across);

                            byte[] temp = diff.cur_row[ci];
                            diff.cur_row[ci]  = diff.prev_row[ci];
                            diff.prev_row[ci] = temp;
                        }
                    }
                }

                // Try to write the MCU-row (or remaining portion of suspended MCU-row).
                uint MCU_count = losslsc.entropy_encode_mcus(cinfo, diff.diff_buf, (uint)yoffset, MCU_col_num, cinfo.MCUs_per_row - MCU_col_num);
                if (MCU_count != cinfo.MCUs_per_row - MCU_col_num)
                {
                    // Suspension forced; update state counters and exit
                    diff.MCU_vert_offset = yoffset;
                    diff.mcu_ctr        += MCU_col_num;
                    return(false);
                }

                // Completed an MCU row, but perhaps not an iMCU row
                diff.mcu_ctr = 0;
            }

            // Completed the iMCU row, advance counters for next one
            diff.iMCU_row_num++;
            start_iMCU_row_c_diff(cinfo);
            return(true);
        }
コード例 #49
0
ファイル: jcapistd.cs プロジェクト: JoshDullen/libjpeg.net
		// Alternate entry point to write raw data.
		// Processes exactly one iMCU row per call, unless suspended.
		public static uint jpeg_write_raw_data(jpeg_compress cinfo, byte[][][] data, uint num_lines)
		{
			if(cinfo.global_state!=STATE.CRAW_OK) ERREXIT1(cinfo, J_MESSAGE_CODE.JERR_BAD_STATE, cinfo.global_state);
			if(cinfo.next_scanline>=cinfo.image_height)
			{
				WARNMS(cinfo, J_MESSAGE_CODE.JWRN_TOO_MUCH_DATA);
				return 0;
			}

			// Call progress monitor hook if present
			if(cinfo.progress!=null)
			{
				cinfo.progress.pass_counter=(int)cinfo.next_scanline;
				cinfo.progress.pass_limit=(int)cinfo.image_height;
				cinfo.progress.progress_monitor(cinfo);
			}

			// Give master control module another chance if this is first call to
			// jpeg_write_raw_data. This lets output of the frame/scan headers be
			// delayed so that application can write COM, etc, markers between
			// jpeg_start_compress and jpeg_write_raw_data.
			if(cinfo.master.call_pass_startup) cinfo.master.pass_startup(cinfo);

			// Verify that at least one iMCU row has been passed.
			uint lines_per_iMCU_row=(uint)cinfo.max_v_samp_factor*cinfo.DCT_size;
			if(num_lines<lines_per_iMCU_row) ERREXIT(cinfo, J_MESSAGE_CODE.JERR_BUFFER_SIZE);

			// Directly compress the row.
			if(!cinfo.coef.compress_data(cinfo, data)) return 0; // If compressor did not consume the whole row, suspend processing.

			// OK, we processed one iMCU row.
			cinfo.next_scanline+=lines_per_iMCU_row;
			return lines_per_iMCU_row;
		}
コード例 #50
0
ファイル: jcsample.cs プロジェクト: mikel785/libjpeg.net
        // Downsample pixel values of a single component.
        // This version handles the standard case of 2:1 horizontal and 2:1 vertical,
        // with smoothing. One row of context is required.
        static void h2v2_smooth_downsample(jpeg_compress cinfo, jpeg_component_info compptr, byte[][] input_data, uint in_row_index, byte[][] output_data, uint out_row_index)
        {
            uint output_cols = compptr.width_in_blocks * cinfo.DCT_size;

            // Expand input data enough to let all the output samples be generated
            // by the standard loop. Special-casing padded output would be more efficient.
            expand_right_edge(input_data, in_row_index - 1, cinfo.max_v_samp_factor + 2, cinfo.image_width, output_cols * 2);

            // We don't bother to form the individual "smoothed" input pixel values;
            // we can directly compute the output which is the average of the four
            // smoothed values. Each of the four member pixels contributes a fraction
            // (1-8*SF) to its own smoothed image and a fraction SF to each of the three
            // other smoothed pixels, therefore a total fraction (1-5*SF)/4 to the final
            // output. The four corner-adjacent neighbor pixels contribute a fraction
            // SF to just one smoothed pixel, or SF/4 to the final output; while the
            // eight edge-adjacent neighbors contribute SF to each of two smoothed
            // pixels, or SF/2 overall. In order to use integer arithmetic, these
            // factors are scaled by 2^16 = 65536.
            // Also recall that SF = smoothing_factor / 1024.
            int memberscale = 16384 - cinfo.smoothing_factor * 80; // scaled (1-5*SF)/4
            int neighscale  = cinfo.smoothing_factor * 16;         // scaled SF/4

            int inrow = (int)in_row_index;

            for (int outrow = 0; outrow < compptr.v_samp_factor; outrow++)
            {
                byte[] outptr    = output_data[out_row_index + outrow];
                byte[] inptr0    = input_data[inrow];
                byte[] inptr1    = input_data[inrow + 1];
                byte[] above_ptr = input_data[inrow - 1];
                byte[] below_ptr = input_data[inrow + 2];

                // Special case for first column: pretend column -1 is same as column 0
                int membersum = inptr0[0] + inptr0[1] + inptr1[0] + inptr1[1];
                int neighsum  = above_ptr[0] + above_ptr[1] + below_ptr[0] + below_ptr[1] + inptr0[0] + inptr0[2] + inptr1[0] + inptr1[2];
                neighsum += neighsum;
                neighsum += above_ptr[0] + above_ptr[2] + below_ptr[0] + below_ptr[2];
                membersum = membersum * memberscale + neighsum * neighscale;
                outptr[0] = (byte)((membersum + 32768) >> 16);
                int iind = 2, oind = 1;

                for (uint colctr = output_cols - 2; colctr > 0; colctr--)
                {
                    // sum of pixels directly mapped to this output element
                    membersum = inptr0[iind] + inptr0[iind + 1] + inptr1[iind] + inptr1[iind + 1];
                    // sum of edge-neighbor pixels
                    neighsum = above_ptr[iind] + above_ptr[iind + 1] + below_ptr[iind] + below_ptr[iind + 1] + inptr0[iind - 1] + inptr0[iind + 2] + inptr1[iind - 1] + inptr1[iind + 2];
                    // The edge-neighbors count twice as much as corner-neighbors
                    neighsum += neighsum;
                    // Add in the corner-neighbors
                    neighsum += above_ptr[iind - 1] + above_ptr[iind + 2] + below_ptr[iind - 1] + below_ptr[iind + 2];
                    // form final output scaled up by 2^16
                    membersum = membersum * memberscale + neighsum * neighscale;
                    // round, descale and output it
                    outptr[oind] = (byte)((membersum + 32768) >> 16);
                    iind        += 2;
                    oind++;
                }

                // Special case for last column
                membersum    = inptr0[iind] + inptr0[iind + 1] + inptr1[iind] + inptr1[iind + 1];
                neighsum     = above_ptr[iind] + above_ptr[iind + 1] + below_ptr[iind] + below_ptr[iind + 1] + inptr0[iind - 1] + inptr0[iind + 1] + inptr1[iind - 1] + inptr1[iind + 1];
                neighsum    += neighsum;
                neighsum    += above_ptr[iind - 1] + above_ptr[iind + 1] + below_ptr[iind - 1] + below_ptr[iind + 1];
                membersum    = membersum * memberscale + neighsum * neighscale;
                outptr[oind] = (byte)((membersum + 32768) >> 16);

                inrow += 2;
            }
        }
コード例 #51
0
ファイル: jcmaster.cs プロジェクト: JoshDullen/libjpeg.net
		// Set up the scan parameters for the current scan
		static void select_scan_parameters(jpeg_compress cinfo)
		{
#if NEED_SCAN_SCRIPT
			if(cinfo.scan_info!=null)
			{
				// Prepare for current scan --- the script is already validated
				my_comp_master master=(my_comp_master)cinfo.master;
				jpeg_scan_info scanptr=cinfo.scan_info[master.scan_number];

				cinfo.comps_in_scan=scanptr.comps_in_scan;
				for(int ci=0; ci<scanptr.comps_in_scan; ci++)
				{
					cinfo.cur_comp_info[ci]=cinfo.comp_info[scanptr.component_index[ci]];
				}
				cinfo.Ss=scanptr.Ss;
				cinfo.Se=scanptr.Se;
				cinfo.Ah=scanptr.Ah;
				cinfo.Al=scanptr.Al;
			}
			else
#endif
			{
				// Prepare for single sequential-JPEG scan containing all components
				if(cinfo.num_components>MAX_COMPS_IN_SCAN) ERREXIT2(cinfo, J_MESSAGE_CODE.JERR_COMPONENT_COUNT, cinfo.num_components, MAX_COMPS_IN_SCAN);
				cinfo.comps_in_scan=cinfo.num_components;
				for(int ci=0; ci<cinfo.num_components; ci++)
				{
					cinfo.cur_comp_info[ci]=cinfo.comp_info[ci];
				}
				if(cinfo.lossless)
				{
#if C_LOSSLESS_SUPPORTED
					// If we fall through to here, the user specified lossless, but did not
					// provide a scan script.
					ERREXIT(cinfo, J_MESSAGE_CODE.JERR_NO_LOSSLESS_SCRIPT);
#endif
				}
				else
				{
					cinfo.process=J_CODEC_PROCESS.JPROC_SEQUENTIAL;
					cinfo.Ss=0;
					cinfo.Se=DCTSIZE2-1;
					cinfo.Ah=0;
					cinfo.Al=0;
				}
			}
		}
コード例 #52
0
ファイル: jcsample.cs プロジェクト: mikel785/libjpeg.net
        // Module initialization routine for downsampling.
        // Note that we must select a routine for each component.
        static void jinit_downsampler(jpeg_compress cinfo)
        {
            my_downsampler downsample = null;

            try
            {
                downsample = new my_downsampler();
            }
            catch
            {
                ERREXIT1(cinfo, J_MESSAGE_CODE.JERR_OUT_OF_MEMORY, 4);
            }

            cinfo.downsample             = downsample;
            downsample.start_pass        = start_pass_downsample;
            downsample.downsample        = sep_downsample;
            downsample.need_context_rows = false;

            if (cinfo.CCIR601_sampling)
            {
                ERREXIT(cinfo, J_MESSAGE_CODE.JERR_CCIR601_NOTIMPL);
            }

            bool smoothok = true;

            // Verify we can handle the sampling factors, and set up method pointers
            for (int ci = 0; ci < cinfo.num_components; ci++)
            {
                jpeg_component_info compptr = cinfo.comp_info[ci];
                if (compptr.h_samp_factor == cinfo.max_h_samp_factor && compptr.v_samp_factor == cinfo.max_v_samp_factor)
                {
#if INPUT_SMOOTHING_SUPPORTED
                    if (cinfo.smoothing_factor != 0)
                    {
                        downsample.methods[ci]       = fullsize_smooth_downsample;
                        downsample.need_context_rows = true;
                    }
                    else
#endif
                    downsample.methods[ci] = fullsize_downsample;
                }
                else if (compptr.h_samp_factor * 2 == cinfo.max_h_samp_factor && compptr.v_samp_factor == cinfo.max_v_samp_factor)
                {
                    smoothok = false;
                    downsample.methods[ci] = h2v1_downsample;
                }
                else if (compptr.h_samp_factor * 2 == cinfo.max_h_samp_factor && compptr.v_samp_factor * 2 == cinfo.max_v_samp_factor)
                {
#if INPUT_SMOOTHING_SUPPORTED
                    if (cinfo.smoothing_factor != 0)
                    {
                        downsample.methods[ci]       = h2v2_smooth_downsample;
                        downsample.need_context_rows = true;
                    }
                    else
#endif
                    downsample.methods[ci] = h2v2_downsample;
                }
                else if ((cinfo.max_h_samp_factor % compptr.h_samp_factor) == 0 && (cinfo.max_v_samp_factor % compptr.v_samp_factor) == 0)
                {
                    smoothok = false;
                    downsample.methods[ci] = int_downsample;
                }
                else
                {
                    ERREXIT(cinfo, J_MESSAGE_CODE.JERR_FRACT_SAMPLE_NOTIMPL);
                }
            }

#if INPUT_SMOOTHING_SUPPORTED
            if (cinfo.smoothing_factor != 0 && !smoothok)
            {
                TRACEMS(cinfo, 0, J_MESSAGE_CODE.JTRC_SMOOTH_NOTIMPL);
            }
#endif
        }
コード例 #53
0
ファイル: jcmaster.cs プロジェクト: JoshDullen/libjpeg.net
		// Per-pass setup.
		// This is called at the beginning of each pass. We determine which modules
		// will be active during this pass and give them appropriate start_pass calls.
		// We also set is_last_pass to indicate whether any more passes will be required.
		static void prepare_for_pass(jpeg_compress cinfo)
		{
			my_comp_master master=(my_comp_master)cinfo.master;

			switch(master.pass_type)
			{
				case c_pass_type.main_pass:
					// Initial pass: will collect input data, and do either Huffman
					// optimization or data output for the first scan.
					select_scan_parameters(cinfo);
					per_scan_setup(cinfo);
					if(!cinfo.raw_data_in)
					{
						cinfo.cconvert.start_pass(cinfo);
						cinfo.downsample.start_pass(cinfo);
						cinfo.prep.start_pass(cinfo, J_BUF_MODE.JBUF_PASS_THRU);
					}
					cinfo.coef.entropy_start_pass(cinfo, cinfo.optimize_coding);
					cinfo.coef.start_pass(cinfo, (master.total_passes>1?J_BUF_MODE.JBUF_SAVE_AND_PASS:J_BUF_MODE.JBUF_PASS_THRU));
					cinfo.main.start_pass(cinfo, J_BUF_MODE.JBUF_PASS_THRU);
					if(cinfo.optimize_coding)
					{
						// No immediate data output; postpone writing frame/scan headers
						master.call_pass_startup=false;
					}
					else
					{
						// Will write frame/scan headers at first jpeg_write_scanlines call
						master.call_pass_startup=true;
					}
					break;
#if ENTROPY_OPT_SUPPORTED
				case c_pass_type.huff_opt_pass:
					// Do Huffman optimization for a scan after the first one.
					select_scan_parameters(cinfo);
					per_scan_setup(cinfo);
					if(cinfo.coef.need_optimization_pass(cinfo))
					{
						cinfo.coef.entropy_start_pass(cinfo, true);
						cinfo.coef.start_pass(cinfo, J_BUF_MODE.JBUF_CRANK_DEST);
						master.call_pass_startup=false;
						break;
					}
					// Special case: Huffman DC refinement scans need no Huffman table
					// and therefore we can skip the optimization pass for them.
					master.pass_type=c_pass_type.output_pass;
					master.pass_number++;
					goto case c_pass_type.output_pass; // FALLTHROUGH
#endif
				case c_pass_type.output_pass:
					// Do a data-output pass.
					// We need not repeat per-scan setup if prior optimization pass did it.
					if(!cinfo.optimize_coding)
					{
						select_scan_parameters(cinfo);
						per_scan_setup(cinfo);
					}
					cinfo.coef.entropy_start_pass(cinfo, false);
					cinfo.coef.start_pass(cinfo, J_BUF_MODE.JBUF_CRANK_DEST);
					// We emit frame/scan headers now
					if(master.scan_number==0) cinfo.marker.write_frame_header(cinfo);
					cinfo.marker.write_scan_header(cinfo);
					master.call_pass_startup=false;
					break;
				default: ERREXIT(cinfo, J_MESSAGE_CODE.JERR_NOT_COMPILED); break;
			}

			master.is_last_pass=(master.pass_number==master.total_passes-1);

			// Set up progress monitor's pass info if present
			if(cinfo.progress!=null)
			{
				cinfo.progress.completed_passes=master.pass_number;
				cinfo.progress.total_passes=master.total_passes;
			}
		}
コード例 #54
0
ファイル: jcsample.cs プロジェクト: mikel785/libjpeg.net
 // Initialize for a downsampling pass.
 static void start_pass_downsample(jpeg_compress cinfo)
 {
     // no work for now
 }
コード例 #55
0
        // Initialize difference buffer controller.
        static void jinit_c_diff_controller(jpeg_compress cinfo, bool need_full_buffer)
        {
            jpeg_lossless_c_codec losslsc = (jpeg_lossless_c_codec)cinfo.coef;
            c_diff_controller     diff    = null;

            try
            {
                diff = new c_diff_controller();
            }
            catch
            {
                ERREXIT1(cinfo, J_MESSAGE_CODE.JERR_OUT_OF_MEMORY, 4);
            }
            losslsc.diff_private    = diff;
            losslsc.diff_start_pass = start_pass_diff;

            // Create the prediction row buffers.
            for (int ci = 0; ci < cinfo.num_components; ci++)
            {
                jpeg_component_info compptr = cinfo.comp_info[ci];
                try
                {
                    diff.cur_row[ci]  = new byte[jround_up(compptr.width_in_blocks, compptr.h_samp_factor)];
                    diff.prev_row[ci] = new byte[jround_up(compptr.width_in_blocks, compptr.h_samp_factor)];
                }
                catch
                {
                    ERREXIT1(cinfo, J_MESSAGE_CODE.JERR_OUT_OF_MEMORY, 4);
                }
            }

            // Create the difference buffer.
            for (int ci = 0; ci < cinfo.num_components; ci++)
            {
                jpeg_component_info compptr = cinfo.comp_info[ci];
                diff.diff_buf[ci] = alloc_darray(cinfo, (uint)jround_up(compptr.width_in_blocks, compptr.h_samp_factor), (uint)compptr.v_samp_factor);

                // Prefill difference rows with zeros. We do this because only actual
                // data is placed in the buffers during prediction/differencing, leaving
                // any dummy differences at the right edge as zeros, which will encode
                // to the smallest amount of data.
                for (int row = 0; row < compptr.v_samp_factor; row++)
                {
                    int c = (int)jround_up(compptr.width_in_blocks, compptr.h_samp_factor);
                    for (int i = 0; i < c; i++)
                    {
                        diff.diff_buf[ci][row][i] = 0;
                    }
                }
            }

            // Create the sample buffer.
            if (need_full_buffer)
            {
#if FULL_SAMP_BUFFER_SUPPORTED
                // Allocate a full-image array for each component,
                // padded to a multiple of samp_factor differences in each direction.
                for (int ci = 0; ci < cinfo.num_components; ci++)
                {
                    jpeg_component_info compptr = cinfo.comp_info[ci];
                    diff.whole_image[ci] = alloc_sarray(cinfo, (uint)jround_up(compptr.width_in_blocks, compptr.h_samp_factor), (uint)jround_up(compptr.height_in_blocks, compptr.v_samp_factor));
                }
#else
                ERREXIT(cinfo, J_MESSAGE_CODE.JERR_BAD_BUFFER_MODE);
#endif
            }
            else
            {
                diff.whole_image[0] = null;            // flag for no arrays
            }
        }
コード例 #56
0
ファイル: jdatadst.cs プロジェクト: JoshDullen/libjpeg.net
		// Prepare for output to a stdio stream.
		// The caller must have already opened the stream, and is responsible
		// for jpeg_destination_mgr it after finishing compression.
		public static void jpeg_stdio_dest(jpeg_compress cinfo, Stream outfile)
		{
			my_destination_mgr dest;

			// The destination object is made permanent so that multiple JPEG images
			// can be written to the same file without re-executing jpeg_stdio_dest.
			// This makes it dangerous to use this manager and a different destination
			// manager serially with the same JPEG object, because their private object
			// sizes may be different. Caveat programmer.
			if(cinfo.dest==null)
			{	
				// first time for this JPEG object?
				cinfo.dest=new my_destination_mgr();
			}

			dest=(my_destination_mgr)cinfo.dest;
			dest.init_destination=init_destination;
			dest.empty_output_buffer=empty_output_buffer;
			dest.term_destination=term_destination;
			dest.outfile=outfile;
		}
コード例 #57
0
ファイル: jcmaster.cs プロジェクト: JoshDullen/libjpeg.net
		// Initialize master compression control.
		static void jinit_c_master_control(jpeg_compress cinfo, bool transcode_only)
		{
			my_comp_master master=null;

			try
			{
				master=new my_comp_master();
			}
			catch
			{
				ERREXIT1(cinfo, J_MESSAGE_CODE.JERR_OUT_OF_MEMORY, 4);
			}

			cinfo.master=master;
			master.prepare_for_pass=prepare_for_pass;
			master.pass_startup=pass_startup;
			master.finish_pass=finish_pass_master;
			master.is_last_pass=false;

			cinfo.DCT_size=cinfo.lossless?1:(uint)DCTSIZE;

			// Validate parameters, determine derived values
			initial_setup(cinfo);

			if(cinfo.scan_info!=null)
			{
#if NEED_SCAN_SCRIPT
				validate_script(cinfo);
#else
				ERREXIT(cinfo, J_MESSAGE_CODE.JERR_NOT_COMPILED);
#endif
			}
			else
			{
				cinfo.process=J_CODEC_PROCESS.JPROC_SEQUENTIAL;
				cinfo.num_scans=1;
			}

			if((cinfo.process==J_CODEC_PROCESS.JPROC_PROGRESSIVE||cinfo.process==J_CODEC_PROCESS.JPROC_LOSSLESS)&&!cinfo.arith_code)
				cinfo.optimize_coding=true; // assume default tables no good for progressive mode or lossless mode; but only in Huffman case!

			// Initialize my private state
			if(transcode_only)
			{ // no main pass in transcoding
				if(cinfo.optimize_coding) master.pass_type=c_pass_type.huff_opt_pass;
				else master.pass_type=c_pass_type.output_pass;
			}
			else
			{ // for normal compression, first pass is always this type:
				master.pass_type=c_pass_type.main_pass;
			}
			master.scan_number=master.pass_number=0;
			if(cinfo.optimize_coding) master.total_passes=cinfo.num_scans*2;
			else master.total_passes=cinfo.num_scans;
		}
コード例 #58
0
        static void jinit_c_scaler(jpeg_compress cinfo)
        {
            jpeg_lossless_c_codec losslsc = (jpeg_lossless_c_codec)cinfo.coef;

            losslsc.scaler_start_pass = scaler_start_pass;
        }
コード例 #59
0
ファイル: jchuff.cs プロジェクト: JoshDullen/libjpeg.net
		// Expand a Huffman table definition into the derived format
		// Compute the derived values for a Huffman table.
		// This routine also performs some validation checks on the table.
		static void jpeg_make_c_derived_tbl(jpeg_compress cinfo, bool isDC, int tblno, ref c_derived_tbl pdtbl)
		{
			// Note that huffsize[] and huffcode[] are filled in code-length order,
			// paralleling the order of the symbols themselves in htbl.huffval[].

			// Find the input Huffman table
			if(tblno<0||tblno>=NUM_HUFF_TBLS) ERREXIT1(cinfo, J_MESSAGE_CODE.JERR_NO_HUFF_TABLE, tblno);
			JHUFF_TBL htbl=isDC?cinfo.dc_huff_tbl_ptrs[tblno]:cinfo.ac_huff_tbl_ptrs[tblno];
			if(htbl==null) ERREXIT1(cinfo, J_MESSAGE_CODE.JERR_NO_HUFF_TABLE, tblno);

			// Allocate a workspace if we haven't already done so.
			if(pdtbl==null)
			{
				try
				{
					pdtbl=new c_derived_tbl();
				}
				catch
				{
					ERREXIT1(cinfo, J_MESSAGE_CODE.JERR_OUT_OF_MEMORY, 4);
				}
			}

			c_derived_tbl dtbl=pdtbl;

			// Figure C.1: make table of Huffman code length for each symbol
			byte[] huffsize=new byte[257]; 
			int p=0;
			for(byte l=1; l<=16; l++)
			{
				int i=htbl.bits[l];
				// protect against table overrun
				if(i<0||(p+i)>256) ERREXIT(cinfo, J_MESSAGE_CODE.JERR_BAD_HUFF_TABLE);
				while((i--)!=0) huffsize[p++]=l;
			}
			huffsize[p]=0;
			int lastp=p;

			// Figure C.2: generate the codes themselves
			// We also validate that the counts represent a legal Huffman code tree.
			uint[] huffcode=new uint[257];
			uint code=0;
			int si=huffsize[0];
			p=0;
			while(huffsize[p]!=0)
			{
				while(((int)huffsize[p])==si)
				{
					huffcode[p++]=code;
					code++;
				}
				// code is now 1 more than the last code used for codelength si; but
				// it must still fit in si bits, since no code is allowed to be all ones.
				if(((int)code)>=(1<<si)) ERREXIT(cinfo, J_MESSAGE_CODE.JERR_BAD_HUFF_TABLE);
				code<<=1;
				si++;
			}

			// Figure C.3: generate encoding tables
			// These are code and size indexed by symbol value

			// Set all codeless symbols to have code length 0;
			// this lets us detect duplicate VAL entries here, and later
			// allows emit_bits to detect any attempt to emit such symbols.
			for(int i=0; i<256; i++) dtbl.ehufsi[i]=0;

			// This is also a convenient place to check for out-of-range
			// and duplicated VAL entries. We allow 0..255 for AC symbols
			// but only 0..16 for DC. (We could constrain them further
			// based on data depth and mode, but this seems enough.)
			int maxsymbol=isDC?16:255;

			for(p=0; p<lastp; p++)
			{
				int i=htbl.huffval[p];
				if(i<0||i>maxsymbol||dtbl.ehufsi[i]!=0) ERREXIT(cinfo, J_MESSAGE_CODE.JERR_BAD_HUFF_TABLE);
				dtbl.ehufco[i]=huffcode[p];
				dtbl.ehufsi[i]=huffsize[p];
			}
		}
コード例 #60
0
ファイル: jcparam.cs プロジェクト: mikel785/libjpeg.net
 // Set or change the 'quality' (quantization) setting, using default tables
 // and a straight percentage-scaling quality scale. In most cases it's better
 // to use jpeg_set_quality (below); this entry point is provided for
 // applications that insist on a linear percentage scaling.
 public static void jpeg_set_linear_quality(jpeg_compress cinfo, int scale_factor, bool force_baseline)
 {
     // Set up two quantization tables using the specified scaling
     jpeg_add_quant_table(cinfo, 0, std_luminance_quant_tbl, scale_factor, force_baseline);
     jpeg_add_quant_table(cinfo, 1, std_chrominance_quant_tbl, scale_factor, force_baseline);
 }