ReadRawStrip() public method

Reads the undecoded contents of a strip of data from an open TIFF file/stream and places specified amount of read bytes into the user supplied buffer.

The value of strip is a "raw strip number". That is, the caller must take into account whether or not the data are organized in separate planes (TiffTag.PLANARCONFIG = PlanarConfig.SEPARATE). ComputeStrip automatically does this when converting an (row, plane) to a strip index.

To read a full strip of data the data buffer should typically be at least as large as the number returned by RawStripSize. If the -1 passed in count parameter, the whole strip will be read. You should be sure you have enough space allocated for the buffer.

public ReadRawStrip ( int strip, byte buffer, int offset, int count ) : int
strip int The zero-based index of the strip to read.
buffer byte The buffer to place read bytes to.
offset int The zero-based byte offset in buffer at which to begin storing /// read bytes.
count int The maximum number of read bytes to be stored to buffer.
return int
示例#1
0
文件: T2P.cs 项目: dronab/libtiff.net
        /*
        This function reads the raster image data from the input TIFF for an image and writes 
        the data to the output PDF XObject image dictionary stream.  It returns the amount written 
        or zero on error.
        */
        private int readwrite_pdf_image(Tiff input)
        {
            byte[] buffer = null;
            int bufferoffset = 0;
            int stripcount = 0;
            int max_striplength = 0;
            FieldValue[] result = null;

            if (m_pdf_transcode == t2p_transcode_t.T2P_TRANSCODE_RAW)
            {
                if (m_pdf_compression == t2p_compress_t.T2P_COMPRESS_G4)
                {
                    buffer = new byte [m_tiff_datasize];
                    input.ReadRawStrip(0, buffer, 0, m_tiff_datasize);
                    if (m_tiff_fillorder == FillOrder.LSB2MSB)
                    {
                        /*
                        * make sure is lsb-to-msb
                        * bit-endianness fill order
                        */
                        Tiff.ReverseBits(buffer, m_tiff_datasize);
                    }
                    
                    writeToFile(buffer, m_tiff_datasize);
                    return m_tiff_datasize;
                }

                if (m_pdf_compression == t2p_compress_t.T2P_COMPRESS_ZIP)
                {
                    buffer = new byte [m_tiff_datasize];
                    input.ReadRawStrip(0, buffer, 0, m_tiff_datasize);
                    if (m_tiff_fillorder == FillOrder.LSB2MSB)
                        Tiff.ReverseBits(buffer, m_tiff_datasize);

                    writeToFile(buffer, m_tiff_datasize);
                    return m_tiff_datasize;
                }
                
                if (m_tiff_compression == Compression.JPEG)
                {
                    buffer = new byte [m_tiff_datasize];
                    result = input.GetField(TiffTag.JPEGTABLES);
                    if (result != null)
                    {
                        int count = result[0].ToInt();
                        byte[] jpt = result[1].ToByteArray();
                        if (count > 4)
                        {
                            Buffer.BlockCopy(jpt, 0, buffer, 0, count);
                            bufferoffset += count - 2;
                        }
                    }

                    stripcount = input.NumberOfStrips();
                    result = input.GetField(TiffTag.STRIPBYTECOUNTS);
                    int[] sbc = result[0].ToIntArray();
                    for (int i = 0; i < stripcount; i++)
                    {
                        if (sbc[i] > max_striplength)
                            max_striplength = sbc[i];
                    }
                    
                    byte[] stripbuffer = new byte [max_striplength];
                    for (int i = 0; i < stripcount; i++)
                    {
                        int striplength = input.ReadRawStrip(i, stripbuffer, 0, -1);
                        if (!process_jpeg_strip(stripbuffer, striplength, buffer, ref bufferoffset, stripcount, i, m_tiff_length))
                        {
                            Tiff.Error(Tiff2PdfConstants.TIFF2PDF_MODULE,
                                "Can't process JPEG data in input file {0}", input.FileName());
                            m_error = true;
                            return 0;
                        }
                    }

                    buffer[bufferoffset++] = 0xff;
                    buffer[bufferoffset++] = 0xd9;
                    writeToFile(buffer, bufferoffset);
                    return bufferoffset;
                }
            }

            int stripsize = 0;
            if (m_pdf_sample == t2p_sample_t.T2P_SAMPLE_NOTHING)
            {
                buffer = new byte [m_tiff_datasize];
                stripsize = input.StripSize();
                stripcount = input.NumberOfStrips();
                for (int i = 0; i < stripcount; i++)
                {
                    int read = input.ReadEncodedStrip(i, buffer, bufferoffset, stripsize);
                    if (read == -1)
                    {
                        Tiff.Error(Tiff2PdfConstants.TIFF2PDF_MODULE,
                            "Error on decoding strip {0} of {1}", i, input.FileName());
                        m_error = true;
                        return 0;
                    }

                    bufferoffset += read;
                }
            }
            else
            {
                byte[] samplebuffer = null;
                bool dataready = false;

                if ((m_pdf_sample & t2p_sample_t.T2P_SAMPLE_PLANAR_SEPARATE_TO_CONTIG) != 0)
                {
                    int sepstripsize = input.StripSize();
                    int sepstripcount = input.NumberOfStrips();

                    stripsize = sepstripsize * m_tiff_samplesperpixel;
                    stripcount = sepstripcount / m_tiff_samplesperpixel;

                    buffer = new byte [m_tiff_datasize];
                    samplebuffer = new byte [stripsize];
                    for (int i = 0; i < stripcount; i++)
                    {
                        int samplebufferoffset = 0;
                        for (int j = 0; j < m_tiff_samplesperpixel; j++)
                        {
                            int read = input.ReadEncodedStrip(i + j * stripcount, samplebuffer, samplebufferoffset, sepstripsize);
                            if (read == -1)
                            {
                                Tiff.Error(Tiff2PdfConstants.TIFF2PDF_MODULE,
                                    "Error on decoding strip {0} of {1}", 
                                    i + j * stripcount, input.FileName());
                                m_error = true;
                                return 0;
                            }
                            samplebufferoffset += read;
                        }

                        sample_planar_separate_to_contig(buffer, bufferoffset, samplebuffer, samplebufferoffset);
                        bufferoffset += samplebufferoffset;
                    }

                    dataready = true;
                }

                if (!dataready)
                {
                    buffer = new byte [m_tiff_datasize];
                    stripsize = input.StripSize();
                    stripcount = input.NumberOfStrips();
                    for (int i = 0; i < stripcount; i++)
                    {
                        int read = input.ReadEncodedStrip(i, buffer, bufferoffset, stripsize);
                        if (read == -1)
                        {
                            Tiff.Error(Tiff2PdfConstants.TIFF2PDF_MODULE,
                                "Error on decoding strip {0} of {1}", i, input.FileName());
                            m_error = true;
                            return 0;
                        }

                        bufferoffset += read;
                    }

                    if ((m_pdf_sample & t2p_sample_t.T2P_SAMPLE_REALIZE_PALETTE) != 0)
                    {
                        samplebuffer = Tiff.Realloc(buffer, m_tiff_datasize * m_tiff_samplesperpixel);
                        buffer = samplebuffer;
                        m_tiff_datasize *= m_tiff_samplesperpixel;
                        sample_realize_palette(buffer);
                    }

                    if ((m_pdf_sample & t2p_sample_t.T2P_SAMPLE_RGBA_TO_RGB) != 0)
                        m_tiff_datasize = sample_rgba_to_rgb(buffer, m_tiff_width * m_tiff_length);

                    if ((m_pdf_sample & t2p_sample_t.T2P_SAMPLE_RGBAA_TO_RGB) != 0)
                        m_tiff_datasize = sample_rgbaa_to_rgb(buffer, m_tiff_width * m_tiff_length);

                    if ((m_pdf_sample & t2p_sample_t.T2P_SAMPLE_YCBCR_TO_RGB) != 0)
                    {
                        samplebuffer = Tiff.Realloc(buffer, m_tiff_width * m_tiff_length * 4);
                        buffer = samplebuffer;

                        int[] buffer32 = Tiff.ByteArrayToInts(buffer, 0, m_tiff_width * m_tiff_length * 4);
                        if (!input.ReadRGBAImageOriented(m_tiff_width, m_tiff_length, buffer32, Orientation.TOPLEFT, false))
                        {
                            Tiff.Error(Tiff2PdfConstants.TIFF2PDF_MODULE,
                                "Can't use ReadRGBAImageOriented to extract RGB image from {0}",
                                input.FileName());
                            m_error = true;
                            return 0;
                        }

                        Tiff.IntsToByteArray(buffer32, 0, m_tiff_width * m_tiff_length, buffer, 0);

                        m_tiff_datasize = sample_abgr_to_rgb(buffer, m_tiff_width * m_tiff_length);
                    }

                    if ((m_pdf_sample & t2p_sample_t.T2P_SAMPLE_LAB_SIGNED_TO_UNSIGNED) != 0)
                        m_tiff_datasize = sample_lab_signed_to_unsigned(buffer, m_tiff_width * m_tiff_length);
                }
            }

            disable(m_output);
            m_output.SetField(TiffTag.PHOTOMETRIC, m_tiff_photometric);
            m_output.SetField(TiffTag.BITSPERSAMPLE, m_tiff_bitspersample);
            m_output.SetField(TiffTag.SAMPLESPERPIXEL, m_tiff_samplesperpixel);
            m_output.SetField(TiffTag.IMAGEWIDTH, m_tiff_width);
            m_output.SetField(TiffTag.IMAGELENGTH, m_tiff_length);
            m_output.SetField(TiffTag.ROWSPERSTRIP, m_tiff_length);
            m_output.SetField(TiffTag.PLANARCONFIG, PlanarConfig.CONTIG);
            m_output.SetField(TiffTag.FILLORDER, FillOrder.MSB2LSB);

            switch (m_pdf_compression)
            {
                case t2p_compress_t.T2P_COMPRESS_NONE:
                    m_output.SetField(TiffTag.COMPRESSION, Compression.NONE);
                    break;
                
                case t2p_compress_t.T2P_COMPRESS_G4:
                    m_output.SetField(TiffTag.COMPRESSION, Compression.CCITTFAX4);
                    break;
                
                case t2p_compress_t.T2P_COMPRESS_JPEG:
                    if (m_tiff_photometric == Photometric.YCBCR)
                    {
                        result = input.GetField(TiffTag.YCBCRSUBSAMPLING);
                        if (result != null)
                        {
                            short hor = result[0].ToShort();
                            short ver = result[1].ToShort();
                            if (hor != 0 && ver != 0)
                                m_output.SetField(TiffTag.YCBCRSUBSAMPLING, hor, ver);
                        }

                        result = input.GetField(TiffTag.REFERENCEBLACKWHITE);
                        if (result != null)
                        {
                            float[] xfloatp = result[0].ToFloatArray();
                            m_output.SetField(TiffTag.REFERENCEBLACKWHITE, xfloatp);
                        }
                    }

                    if (!m_output.SetField(TiffTag.COMPRESSION, Compression.JPEG))
                    {
                        Tiff.Error(Tiff2PdfConstants.TIFF2PDF_MODULE,
                            "Unable to use JPEG compression for input {0} and output {1}",
                            input.FileName(), m_output.FileName());
                        m_error = true;
                        return 0;
                    }

                    m_output.SetField(TiffTag.JPEGTABLESMODE, 0);

                    if ((m_pdf_colorspace & (t2p_cs_t.T2P_CS_RGB | t2p_cs_t.T2P_CS_LAB)) != 0)
                    {
                        m_output.SetField(TiffTag.PHOTOMETRIC, Photometric.YCBCR);

                        if (m_tiff_photometric != Photometric.YCBCR)
                            m_output.SetField(TiffTag.JPEGCOLORMODE, JpegColorMode.RGB);
                        else
                            m_output.SetField(TiffTag.JPEGCOLORMODE, JpegColorMode.RAW);
                    }

                    if (m_pdf_defaultcompressionquality != 0)
                        m_output.SetField(TiffTag.JPEGQUALITY, m_pdf_defaultcompressionquality);

                    break;
                
                case t2p_compress_t.T2P_COMPRESS_ZIP:
                    m_output.SetField(TiffTag.COMPRESSION, Compression.DEFLATE);
                    if (m_pdf_defaultcompressionquality % 100 != 0)
                        m_output.SetField(TiffTag.PREDICTOR, m_pdf_defaultcompressionquality % 100);
                    
                    if (m_pdf_defaultcompressionquality / 100 != 0)
                        m_output.SetField(TiffTag.ZIPQUALITY, (m_pdf_defaultcompressionquality / 100));

                    break;
                
                default:
                    break;
            }

            enable(m_output);
            m_outputwritten = 0;

            if (m_pdf_compression == t2p_compress_t.T2P_COMPRESS_JPEG && m_tiff_photometric == Photometric.YCBCR)
                bufferoffset = m_output.WriteEncodedStrip(0, buffer, stripsize * stripcount);
            else
                bufferoffset = m_output.WriteEncodedStrip(0, buffer, m_tiff_datasize);

            buffer = null;

            if (bufferoffset == -1)
            {
                Tiff.Error(Tiff2PdfConstants.TIFF2PDF_MODULE,
                    "Error writing encoded strip to output PDF {0}", m_output.FileName());
                m_error = true;
                return 0;
            }

            return m_outputwritten;
        }
示例#2
0
文件: Tiff.cs 项目: dtegunov/warp
 private static int readStrip(Tiff image, int stripNumber, byte[] buffer, int offset, bool encoded)
 {
     if (encoded)
         return image.ReadEncodedStrip(stripNumber, buffer, offset, buffer.Length - offset);
     else
         return image.ReadRawStrip(stripNumber, buffer, offset, buffer.Length - offset);
 }