private int m_next_row; /* index of next row to fill/empty in strip */
/// <summary>
/// Initialize postprocessing controller.
/// </summary>
public jpeg_d_post_controller(jpeg_decompress_struct cinfo, bool need_full_buffer)
{
m_cinfo = cinfo;
/* Create the quantization buffer, if needed */
if (cinfo.m_quantize_colors)
{
/* The buffer strip height is max_v_samp_factor, which is typically
* an efficient number of rows for upsampling to return.
* (In the presence of output rescaling, we might want to be smarter?)
*/
m_strip_height = cinfo.m_max_v_samp_factor;
if (need_full_buffer)
{
/* Two-pass color quantization: need full-image storage. */
/* We round up the number of rows to a multiple of the strip height. */
m_whole_image = jpeg_common_struct.CreateSamplesArray(
cinfo.m_output_width * cinfo.m_out_color_components,
JpegUtils.jround_up(cinfo.m_output_height, m_strip_height));
m_whole_image.ErrorProcessor = cinfo;
}
else
{
/* One-pass color quantization: just make a strip buffer. */
m_buffer = jpeg_common_struct.AllocJpegSamples(
cinfo.m_output_width * cinfo.m_out_color_components, m_strip_height);
}
}
}
public jpeg_d_coef_controller(jpeg_decompress_struct cinfo, bool need_full_buffer)
{
m_cinfo = cinfo;
/* Create the coefficient buffer. */
if (need_full_buffer)
{
/* Allocate a full-image virtual array for each component, */
/* padded to a multiple of samp_factor DCT blocks in each direction. */
/* Note we ask for a pre-zeroed array. */
for (int ci = 0; ci < cinfo.m_num_components; ci++)
{
m_whole_image[ci] = jpeg_common_struct.CreateBlocksArray(
JpegUtils.jround_up(cinfo.Comp_info[ci].Width_in_blocks, cinfo.Comp_info[ci].H_samp_factor),
JpegUtils.jround_up(cinfo.Comp_info[ci].height_in_blocks, cinfo.Comp_info[ci].V_samp_factor));
m_whole_image[ci].ErrorProcessor = cinfo;
}
m_useDummyConsumeData = false;
m_decompressor = DecompressorType.Ordinary;
m_coef_arrays = m_whole_image; /* link to virtual arrays */
}
else
{
/* We only need a single-MCU buffer. */
for (int i = 0; i < JpegConstants.D_MAX_BLOCKS_IN_MCU; i++)
{
m_MCU_buffer[i] = new JBLOCK();
}
m_useDummyConsumeData = true;
m_decompressor = DecompressorType.OnePass;
m_coef_arrays = null; /* flag for no virtual arrays */
}
}
// the algorithm flow is based on:
// https://bitmiracle.github.io/libjpeg.net/help/articles/KB/decompression-details.html
private DecompressionResult DecompressJpgToRaw(byte[] image)
{
var cinfo = new jpeg_decompress_struct(new jpeg_error_mgr());
using (var memoryStream = new MemoryStream(image))
{
cinfo.jpeg_stdio_src(memoryStream);
cinfo.jpeg_read_header(true);
cinfo.Out_color_space = J_COLOR_SPACE.JCS_RGB;
cinfo.jpeg_start_decompress();
// there are 3 components: R, G, B
var rowStride = 3 * cinfo.Output_width;
var result = new byte[rowStride * cinfo.Output_height];
var resultOffset = 0;
var buffer = new byte[1][];
buffer[0] = new byte[rowStride];
while (cinfo.Output_scanline < cinfo.Output_height)
{
var ct = cinfo.jpeg_read_scanlines(buffer, 1);
if (ct > 0)
{
Array.Copy(buffer[0], 0, result, resultOffset, buffer[0].Length);
resultOffset += buffer[0].Length;
}
}
cinfo.jpeg_finish_decompress();
return(new DecompressionResult(result, cinfo.Output_width, cinfo.Output_height));
}
}
private int m_rows_to_go; /* counts rows remaining in image */
public my_merged_upsampler(jpeg_decompress_struct cinfo)
{
m_cinfo = cinfo;
m_need_context_rows = false;
m_out_row_width = cinfo.m_output_width * cinfo.m_out_color_components;
if (cinfo.m_max_v_samp_factor == 2)
{
m_use_2v_upsample = true;
/* Allocate a spare row buffer */
m_spare_row = new byte[m_out_row_width];
}
else
{
m_use_2v_upsample = false;
}
if (cinfo.m_jpeg_color_space == J_COLOR_SPACE.JCS_BG_YCC)
{
build_bg_ycc_rgb_table();
}
else
{
build_ycc_rgb_table();
}
}
// Fill an input buffer from a stream.
private static Int fill_input_buffer(ref jpeg_decompress_struct cinfo)
{
int len;
StreamState state = GetStreamState(ref cinfo);
if (!(state.sawEOF))
{
len = state.stream.Read
(state.buffer, 0, state.buffer.Length);
if (len > 0)
{
Marshal.Copy(state.buffer, 0, state.buf, len);
cinfo.src->next_input_byte = state.buf;
cinfo.src->bytes_in_buffer = (size_t)len;
return((Int)1);
}
state.sawEOF = true;
}
// Insert an EOI marker to indicate end of stream to "libjpeg".
Marshal.WriteByte(state.buf, 0, (byte)0xFF);
Marshal.WriteByte(state.buf, 1, (byte)0xD9);
cinfo.src->next_input_byte = state.buf;
cinfo.src->bytes_in_buffer = (size_t)2;
return((Int)1);
}
private int m_iMCU_row_ctr; /* counts iMCU rows to detect image top/bot */
public jpeg_d_main_controller(jpeg_decompress_struct cinfo)
{
m_cinfo = cinfo;
/* Allocate the workspace.
* ngroups is the number of row groups we need.
*/
int ngroups = cinfo.m_min_DCT_scaled_size;
if (cinfo.m_upsample.NeedContextRows())
{
if (cinfo.m_min_DCT_scaled_size < 2) /* unsupported, see comments above */
{
cinfo.ERREXIT(J_MESSAGE_CODE.JERR_NOTIMPL);
}
alloc_funny_pointers(); /* Alloc space for xbuffer[] lists */
ngroups = cinfo.m_min_DCT_scaled_size + 2;
}
for (int ci = 0; ci < cinfo.m_num_components; ci++)
{
/* height of a row group of component */
int rgroup = (cinfo.Comp_info[ci].V_samp_factor * cinfo.Comp_info[ci].DCT_scaled_size) / cinfo.m_min_DCT_scaled_size;
m_buffer[ci] = jpeg_common_struct.AllocJpegSamples(
cinfo.Comp_info[ci].Width_in_blocks * cinfo.Comp_info[ci].DCT_scaled_size,
rgroup * ngroups);
}
}
private d_derived_tbl m_ac_derived_tbl; /* active table during an AC scan */
public phuff_entropy_decoder(jpeg_decompress_struct cinfo)
{
m_cinfo = cinfo;
/* Mark derived tables unallocated */
for (int i = 0; i < JpegConstants.NUM_HUFF_TBLS; i++)
{
m_derived_tbls[i] = null;
}
/* Create progression status table */
cinfo.m_coef_bits = new int[cinfo.m_num_components][];
for (int i = 0; i < cinfo.m_num_components; i++)
{
cinfo.m_coef_bits[i] = new int[JpegConstants.DCTSIZE2];
}
for (int ci = 0; ci < cinfo.m_num_components; ci++)
{
for (int i = 0; i < JpegConstants.DCTSIZE2; i++)
{
cinfo.m_coef_bits[ci][i] = -1;
}
}
}
public jpeg_d_coef_controller(jpeg_decompress_struct cinfo, bool need_full_buffer)
{
m_cinfo = cinfo;
/* Create the coefficient buffer. */
if (need_full_buffer)
{
/* Allocate a full-image virtual array for each component, */
/* padded to a multiple of samp_factor DCT blocks in each direction. */
/* Note we ask for a pre-zeroed array. */
for (int ci = 0; ci < cinfo.m_num_components; ci++)
{
m_whole_image[ci] = jpeg_common_struct.CreateBlocksArray(
JpegUtils.jround_up(cinfo.Comp_info[ci].Width_in_blocks, cinfo.Comp_info[ci].H_samp_factor),
JpegUtils.jround_up(cinfo.Comp_info[ci].height_in_blocks, cinfo.Comp_info[ci].V_samp_factor));
m_whole_image[ci].ErrorProcessor = cinfo;
}
m_useDummyConsumeData = false;
m_decompressor = DecompressorType.Ordinary;
m_coef_arrays = m_whole_image; /* link to virtual arrays */
}
else
{
/* We only need a single-MCU buffer. */
for (int i = 0; i < JpegConstants.D_MAX_BLOCKS_IN_MCU; i++)
m_MCU_buffer[i] = new JBLOCK();
m_useDummyConsumeData = true;
m_decompressor = DecompressorType.OnePass;
m_coef_arrays = null; /* flag for no virtual arrays */
}
}
private bool m_on_odd_row; /* flag to remember which row we are on */
/// <summary>
/// Module initialization routine for 1-pass color quantization.
/// </summary>
/// <param name="cinfo">The cinfo.</param>
public my_1pass_cquantizer(jpeg_decompress_struct cinfo)
{
m_cinfo = cinfo;
m_fserrors[0] = null; /* Flag FS workspace not allocated */
m_odither[0] = null; /* Also flag odither arrays not allocated */
/* Make sure my internal arrays won't overflow */
if (cinfo.m_out_color_components > MAX_Q_COMPS)
{
cinfo.ERREXIT(J_MESSAGE_CODE.JERR_QUANT_COMPONENTS, MAX_Q_COMPS);
}
/* Make sure colormap indexes can be represented by JSAMPLEs */
if (cinfo.m_desired_number_of_colors > (JpegConstants.MAXJSAMPLE + 1))
{
cinfo.ERREXIT(J_MESSAGE_CODE.JERR_QUANT_MANY_COLORS, JpegConstants.MAXJSAMPLE + 1);
}
/* Create the colormap and color index table. */
create_colormap();
create_colorindex();
/* Allocate Floyd-Steinberg workspace now if requested.
* We do this now since it is FAR storage and may affect the memory
* manager's space calculations. If the user changes to FS dither
* mode in a later pass, we will allocate the space then, and will
* possibly overrun the max_memory_to_use setting.
*/
if (cinfo.m_dither_mode == J_DITHER_MODE.JDITHER_FS)
{
alloc_fs_workspace();
}
}
private void Enc(string inputPath, string outputPath, byte[] data)
{
var input = new jpeg_decompress_struct();
using (var fileStream = new FileStream(inputPath, FileMode.Open))
{
input.jpeg_stdio_src(fileStream);
input.jpeg_read_header(false);
var coefficients = input.jpeg_read_coefficients();
var channels = coefficients.Take(3).Select(JpegHelper.GetBuffer).ToArray();
Encrypt(channels, data);
var output = new jpeg_compress_struct();
using (var outfile = new FileStream(outputPath, FileMode.Create))
{
output.jpeg_stdio_dest(outfile);
input.jpeg_copy_critical_parameters(output);
output.jpeg_write_coefficients(coefficients);
output.jpeg_finish_compress();
}
}
}
/// <summary>
/// Get the Huffman tables using reflection for a specific component (AC, DC)
/// </summary>
/// <returns></returns>
public static HuffmanTable[] GetHuffmanTables(string JpegFilePath)
{
FileStream objFileStreamMegaMap = File.Create(JpegFilePath);
jpeg_decompress_struct jpds = new jpeg_decompress_struct();
jpeg_compress_struct jpcs = new jpeg_compress_struct();
jpcs.jpeg_stdio_dest(objFileStreamMegaMap);
jpds.jpeg_copy_critical_parameters(jpcs);
jpds.jpeg_finish_decompress();
objFileStreamMegaMap.Close();
// DC Huffman tables
JHUFF_TBL[] jpeg_dc_huffman_tables = jpcs.Dc_huff_tbl_ptrs;
var comp = HuffmanTable.EnumComponent.DC;
var htdc = getHTables(jpeg_dc_huffman_tables, comp);
// AC Huffman tables
JHUFF_TBL[] jpeg_ac_huffman_tables = jpcs.Ac_huff_tbl_ptrs;
comp = HuffmanTable.EnumComponent.AC;
var htac = getHTables(jpeg_ac_huffman_tables, comp);
HuffmanTable[] hts = new HuffmanTable[htdc.Length + htac.Length];
Array.Copy(htdc, hts, htdc.Length);
Array.Copy(htac, 0, hts, htdc.Length, htac.Length);
return(hts);
}
/// <summary>
/// The DCT coefficients are returned in a structure where the different components are separated in 2D arrays od shorts[][].
/// The first dimension of the array contains the Blocks and the second dimension the 64 values for that block.
/// </summary>
/// <returns></returns>
public static DCTCoefficients GetDctCoefficients(string JpegFilePath)
{
jpeg_decompress_struct jpds = new jpeg_decompress_struct();
FileStream fileStreamImg = new FileStream(JpegFilePath, FileMode.Open, FileAccess.Read);
jpds.jpeg_stdio_src(fileStreamImg);
jpds.jpeg_read_header(true);
// DCT coefficients
var jBlock = jpds.jpeg_read_coefficients();
// Initialize the list for all the dct
var dctFull = new List <short>();
var dctFullDc = new List <short>();
var dctFullAc = new List <short>();
// Get coeffs and fill the list _dctFull
List <short[]> dctCr = readDctCoeffs(EnumStegoChannel.Cr, jBlock, dctFull, dctFullDc, dctFullAc);
List <short[]> dctCb = readDctCoeffs(EnumStegoChannel.Cb, jBlock, dctFull, dctFullDc, dctFullAc);
List <short[]> dctY = readDctCoeffs(EnumStegoChannel.Y, jBlock, dctFull, dctFullDc, dctFullAc);
// Close decompress and filestream
jpds.jpeg_finish_decompress();
fileStreamImg.Close();
// Return DCT coefficients
DCTCoefficients dctCoeffs = new DCTCoefficients
{
DctY = dctY.ToArray(),
DctCb = dctCb.ToArray(),
DctCr = dctCr.ToArray(),
DctFull = dctFull.ToArray(),
DctFullDc = dctFullDc.ToArray(),
DctFullAc = dctFullAc.ToArray()
};
return(dctCoeffs);
}
private int m_next_row; /* index of next row to fill/empty in strip */
/// <summary>
/// Initialize postprocessing controller.
/// </summary>
public jpeg_d_post_controller(jpeg_decompress_struct cinfo, bool need_full_buffer)
{
m_cinfo = cinfo;
/* Create the quantization buffer, if needed */
if (cinfo.m_quantize_colors)
{
/* The buffer strip height is max_v_samp_factor, which is typically
* an efficient number of rows for upsampling to return.
* (In the presence of output rescaling, we might want to be smarter?)
*/
m_strip_height = cinfo.m_max_v_samp_factor;
if (need_full_buffer)
{
/* Two-pass color quantization: need full-image storage. */
/* We round up the number of rows to a multiple of the strip height. */
m_whole_image = jpeg_common_struct.CreateSamplesArray(
cinfo.m_output_width * cinfo.m_out_color_components,
JpegUtils.jround_up(cinfo.m_output_height, m_strip_height));
m_whole_image.ErrorProcessor = cinfo;
}
else
{
/* One-pass color quantization: just make a strip buffer. */
m_buffer = jpeg_common_struct.AllocJpegSamples(
cinfo.m_output_width * cinfo.m_out_color_components, m_strip_height);
}
}
}
/// <summary>
/// Get the Quantization tables using reflection per component
/// </summary>
/// <returns></returns>
public static short[][] GetQuantizationTables(string JpegFilePath)
{
FileStream objFileStreamMegaMap = File.Create(JpegFilePath);
jpeg_decompress_struct jpds = new jpeg_decompress_struct();
jpeg_compress_struct jpcs = new jpeg_compress_struct();
jpcs.jpeg_stdio_dest(objFileStreamMegaMap);
jpds.jpeg_copy_critical_parameters(jpcs);
jpds.jpeg_finish_decompress();
objFileStreamMegaMap.Close();
JQUANT_TBL[] jpeg_quant_tables = jpcs.Quant_tbl_ptrs;
int qCount = jpeg_quant_tables.Length;
short[][] qt = new short[qCount][];
BindingFlags bindFlags = BindingFlags.Instance | BindingFlags.Public | BindingFlags.NonPublic | BindingFlags.Static;
int idx = 0;
while (null != jpeg_quant_tables[idx])
{
Type type = jpeg_quant_tables[idx].GetType();
object instance = jpeg_quant_tables[idx];
FieldInfo field = type.GetField("quantval", bindFlags);
qt[idx] = field.GetValue(instance) as short[];
++idx;
}
var qTables = qt.Where(tab => null != tab).ToArray();
return(qTables);
}
/// <summary>
/// This is the default resync_to_restart method for data source
/// managers to use if they don't have any better approach.
/// </summary>
/// <param name="cinfo">An instance of <see cref="jpeg_decompress_struct"/></param>
/// <param name="desired">The desired</param>
/// <returns><c>false</c> if suspension is required.</returns>
/// <remarks>That method assumes that no backtracking is possible.
/// Some data source managers may be able to back up, or may have
/// additional knowledge about the data which permits a more
/// intelligent recovery strategy; such managers would
/// presumably supply their own resync method.<br/><br/>
/// read_restart_marker calls resync_to_restart if it finds a marker other than
/// the restart marker it was expecting. (This code is *not* used unless
/// a nonzero restart interval has been declared.) cinfo.unread_marker is
/// the marker code actually found (might be anything, except 0 or FF).
/// The desired restart marker number (0..7) is passed as a parameter.<br/><br/>
/// This routine is supposed to apply whatever error recovery strategy seems
/// appropriate in order to position the input stream to the next data segment.
/// Note that cinfo.unread_marker is treated as a marker appearing before
/// the current data-source input point; usually it should be reset to zero
/// before returning.<br/><br/>
/// This implementation is substantially constrained by wanting to treat the
/// input as a data stream; this means we can't back up. Therefore, we have
/// only the following actions to work with:<br/>
/// 1. Simply discard the marker and let the entropy decoder resume at next
/// byte of file.<br/>
/// 2. Read forward until we find another marker, discarding intervening
/// data. (In theory we could look ahead within the current bufferload,
/// without having to discard data if we don't find the desired marker.
/// This idea is not implemented here, in part because it makes behavior
/// dependent on buffer size and chance buffer-boundary positions.)<br/>
/// 3. Leave the marker unread (by failing to zero cinfo.unread_marker).
/// This will cause the entropy decoder to process an empty data segment,
/// inserting dummy zeroes, and then we will reprocess the marker.<br/>
/// #2 is appropriate if we think the desired marker lies ahead, while #3 is
/// appropriate if the found marker is a future restart marker (indicating
/// that we have missed the desired restart marker, probably because it got
/// corrupted).<br/>
/// We apply #2 or #3 if the found marker is a restart marker no more than
/// two counts behind or ahead of the expected one. We also apply #2 if the
/// found marker is not a legal JPEG marker code (it's certainly bogus data).
/// If the found marker is a restart marker more than 2 counts away, we do #1
/// (too much risk that the marker is erroneous; with luck we will be able to
/// resync at some future point).<br/>
/// For any valid non-restart JPEG marker, we apply #3. This keeps us from
/// overrunning the end of a scan. An implementation limited to single-scan
/// files might find it better to apply #2 for markers other than EOI, since
/// any other marker would have to be bogus data in that case.</remarks>
public override bool resync_to_restart(jpeg_decompress_struct cinfo, int desired)
{
Tiff tif = m_sp.GetTiff();
Tiff.ErrorExt(tif, tif.m_clientdata, "LibJpeg", "Unexpected error");
return(false);
}
public void TestMarkerList()
{
jpeg_decompress_struct cinfo = new jpeg_decompress_struct();
using (FileStream input = new FileStream(Tester.MapOpenPath("PARROTS.JPG"), FileMode.Open))
{
/* Specify data source for decompression */
cinfo.jpeg_stdio_src(input);
const int markerDataLengthLimit = 1000;
cinfo.jpeg_save_markers((int)JPEG_MARKER.COM, markerDataLengthLimit);
cinfo.jpeg_save_markers((int)JPEG_MARKER.APP0, markerDataLengthLimit);
/* Read file header, set default decompression parameters */
cinfo.jpeg_read_header(true);
Assert.AreEqual(cinfo.Marker_list.Count, 3);
int[] expectedMarkerType = { (int)JPEG_MARKER.APP0, (int)JPEG_MARKER.APP0, (int)JPEG_MARKER.COM };
int[] expectedMarkerOriginalLength = { 14, 3072, 10 };
for (int i = 0; i < cinfo.Marker_list.Count; ++i)
{
jpeg_marker_struct marker = cinfo.Marker_list[i];
Assert.IsNotNull(marker);
Assert.AreEqual(marker.Marker, expectedMarkerType[i]);
Assert.AreEqual(marker.OriginalLength, expectedMarkerOriginalLength[i]);
Assert.LessOrEqual(marker.Data.Length, markerDataLengthLimit);
}
}
}
private savable_state m_saved = new savable_state(); /* Other state at start of MCU */
#endregion Fields
#region Constructors
public huff_entropy_decoder(jpeg_decompress_struct cinfo)
{
m_cinfo = cinfo;
/* Mark tables unallocated */
for (int i = 0; i < JpegConstants.NUM_HUFF_TBLS; i++)
m_dc_derived_tbls[i] = m_ac_derived_tbls[i] = null;
}
private bool m_eoi_reached; /* True when EOI has been consumed */
/// <summary>
/// Initialize the input controller module.
/// This is called only once, when the decompression object is created.
/// </summary>
public jpeg_input_controller(jpeg_decompress_struct cinfo)
{
m_cinfo = cinfo;
/* Initialize state: can't use reset_input_controller since we don't
* want to try to reset other modules yet.
*/
m_inheaders = true;
}
private int cur_output_row; /* next row# to write to virtual array */
public bmp_dest_struct(jpeg_decompress_struct cinfo, bool is_os2)
{
this.cinfo = cinfo;
this.is_os2 = is_os2;
if (cinfo.Out_color_space == J_COLOR_SPACE.JCS_GRAYSCALE)
{
m_putGrayRows = true;
}
else if (cinfo.Out_color_space == J_COLOR_SPACE.JCS_RGB)
{
if (cinfo.Quantize_colors)
{
m_putGrayRows = true;
}
else
{
m_putGrayRows = false;
}
}
else
{
cinfo.ERREXIT((int)ADDON_MESSAGE_CODE.JERR_BMP_COLORSPACE);
}
/* Calculate output image dimensions so we can allocate space */
cinfo.jpeg_calc_output_dimensions();
/* Determine width of rows in the BMP file (padded to 4-byte boundary). */
row_width = cinfo.Output_width * cinfo.Output_components;
data_width = row_width;
while ((row_width & 3) != 0)
{
row_width++;
}
pad_bytes = row_width - data_width;
/* Allocate space for inversion array, prepare for write pass */
whole_image = jpeg_common_struct.CreateSamplesArray(row_width, cinfo.Output_height);
whole_image.ErrorProcessor = cinfo;
cur_output_row = 0;
if (cinfo.Progress != null)
{
cdjpeg_progress_mgr progress = cinfo.Progress as cdjpeg_progress_mgr;
if (progress != null)
{
/* count file input as separate pass */
progress.total_extra_passes++;
}
}
/* Create decompressor output buffer. */
buffer = jpeg_common_struct.AllocJpegSamples(row_width, 1);
buffer_height = 1;
}
private bool m_eoi_reached; /* True when EOI has been consumed */
/// <summary>
/// Initialize the input controller module.
/// This is called only once, when the decompression object is created.
/// </summary>
public jpeg_input_controller(jpeg_decompress_struct cinfo)
{
m_cinfo = cinfo;
/* Initialize state: can't use reset_input_controller since we don't
* want to try to reset other modules yet.
*/
m_inheaders = true;
}
private bool m_start_of_file; /* have we gotten any data yet? */
public VirtualStreamSourceManager(jpeg_decompress_struct cinfo, Stream src)
{
m_cinfo = cinfo;
m_buffer = new byte[InputBufferSize];
m_infile = src;
m_infile.Seek(0, SeekOrigin.Begin);
initInternalBuffer(null, 0);
}
public huff_entropy_decoder(jpeg_decompress_struct cinfo)
{
m_cinfo = cinfo;
/* Mark tables unallocated */
for (int i = 0; i < JpegConstants.NUM_HUFF_TBLS; i++)
{
m_dc_derived_tbls[i] = m_ac_derived_tbls[i] = null;
}
}
// Free a source manager.
public static void FreeSourceManager(ref jpeg_decompress_struct cinfo)
{
GCHandle handle = (GCHandle)(cinfo.client_data);
StreamState state = (StreamState)(handle.Target);
Marshal.FreeHGlobal(state.buf);
handle.Free();
Marshal.FreeHGlobal((IntPtr)(cinfo.src));
cinfo.client_data = IntPtr.Zero;
cinfo.src = null;
}
/// <summary>
/// Read next byte
/// </summary>
static int jpeg_getc(jpeg_decompress_struct decompressor)
{
int v;
if (!decompressor.Src.GetByte(out v))
{
decompressor.ERREXIT(J_MESSAGE_CODE.JERR_CANT_SUSPEND);
}
return(v);
}
private byte[] Dec(string inputPath, int len)
{
var input = new jpeg_decompress_struct();
input.jpeg_stdio_src(new FileStream(inputPath, FileMode.Open));
input.jpeg_read_header(false);
var coefficients = input.jpeg_read_coefficients();
var channels = coefficients.Take(3).Select(JpegHelper.GetBuffer).ToArray();
return(Decrypt(channels, len));
}
static void applyOptions(jpeg_decompress_struct decompressor, DecompressOptions options)
{
Debug.Assert(decompressor != null);
Debug.Assert(options != null);
if (options.QuantizeColors)
{
decompressor.Quantize_colors = true;
decompressor.Desired_number_of_colors = options.DesiredNumberOfColors;
}
decompressor.Dct_method = options.DCTMethod;
decompressor.Dither_mode = options.DitherMode;
if (options.Debug)
{
decompressor.Err.Trace_level = 1;
}
if (options.Fast)
{
/* Select recommended processing options for quick-and-dirty output. */
decompressor.Two_pass_quantize = false;
decompressor.Dither_mode = J_DITHER_MODE.JDITHER_ORDERED;
if (!decompressor.Quantize_colors) /* don't override an earlier -colors */
{
decompressor.Desired_number_of_colors = 216;
}
decompressor.Dct_method = JpegConstants.JDCT_FASTEST;
decompressor.Do_fancy_upsampling = false;
}
if (options.Grayscale)
{
decompressor.Out_color_space = J_COLOR_SPACE.JCS_GRAYSCALE;
}
if (options.NoSmooth)
{
decompressor.Do_fancy_upsampling = false;
}
if (options.OnePass)
{
decompressor.Two_pass_quantize = false;
}
if (options.Scaled)
{
decompressor.Scale_num = options.ScaleNumerator;
decompressor.Scale_denom = options.ScaleDenominator;
}
}
// Convert a stream into a source manager.
public static void StreamToSourceManager
(ref jpeg_decompress_struct cinfo, Stream stream,
byte[] prime, int primeLen)
{
// Allocate a state structure and store it in "cinfo".
IntPtr buf = Marshal.AllocHGlobal(4096);
StreamState state = new StreamState();
state.buf = buf;
state.buffer = new byte [4096];
state.stream = stream;
cinfo.client_data = (IntPtr)(GCHandle.Alloc(state));
// We prime the input buffer with the JPEG magic number
// if some higher-level process has already read it.
int len;
if (prime != null)
{
len = primeLen;
Marshal.Copy(prime, 0, buf, len);
}
else
{
len = 0;
}
// Create the managed version of "jpeg_source_mgr".
jpeg_source_mgr mgr = new jpeg_source_mgr();
mgr.next_input_byte = buf;
mgr.bytes_in_buffer = (size_t)len;
mgr.init_source = new init_source_type(init_source);
mgr.fill_input_buffer =
new fill_input_buffer_type(fill_input_buffer);
mgr.skip_input_data =
new skip_input_data_type(skip_input_data);
mgr.resync_to_restart =
new resync_to_restart_type(jpeg_resync_to_restart);
mgr.term_source =
new term_source_type(term_source);
// Convert it into the unmanaged version and store it.
#if __CSCC__
IntPtr umgr = Marshal.AllocHGlobal(sizeof(jpeg_source_mgr));
Marshal.StructureToPtr(mgr, umgr, false);
cinfo.src = (jpeg_source_mgr *)umgr;
#endif
}
public byte[] DecodeJpeg(string inputPath, int len)
{
var input = new jpeg_decompress_struct();
using (var fs = new FileStream(inputPath, FileMode.Open))
{
input.jpeg_stdio_src(fs);
input.jpeg_read_header(false);
var coefficients = input.jpeg_read_coefficients();
var channels = coefficients.Take(3).Select(JpegHelper.GetBuffer).ToArray();
input.jpeg_finish_decompress();
return(DecodeBlocks(channels, len));
}
}
public static void ApplyQuantizationTable(string JpegFilePath, EnumStegoChannel Component = EnumStegoChannel.Y, int ScaleFactor = 50, int[] QuantizationTable = null)
{
var jpds = new jpeg_decompress_struct();
FileStream fileStreamImg = new FileStream(JpegFilePath, FileMode.Open, FileAccess.Read);
jpds.jpeg_stdio_src(fileStreamImg);
jpds.jpeg_read_header(true);
// DCT coefficients
var jBlock = jpds.jpeg_read_coefficients();
jpds.jpeg_finish_decompress();
fileStreamImg.Close();
if (null == QuantizationTable)
{
switch (Component)
{
case EnumStegoChannel.Y:
QuantizationTable = _qLuminance;
break;
case EnumStegoChannel.Cb:
case EnumStegoChannel.Cr:
QuantizationTable = _qChromiance;
break;
}
}
// Get fle info
FileInfo fInfo = new FileInfo(JpegFilePath);
string dir = fInfo.DirectoryName;
string fNane = fInfo.Name;
string stegFName = $"steg_{DateTime.Now.ToString("yyyyMMddHHmm")}_{fNane}";
string stegJpegFilePath = Path.Combine(dir, stegFName);
// Compress process
FileStream fileStream = File.Create(stegJpegFilePath);
jpeg_compress_struct jpcs = new jpeg_compress_struct();
jpcs.jpeg_stdio_dest(fileStream);
jpds.jpeg_copy_critical_parameters(jpcs);
jpcs.jpeg_write_coefficients(jBlock);
jpcs.jpeg_finish_compress();
fileStream.Close();
jpds.jpeg_abort_decompress();
}
// Generic versions of jpeg_abort and jpeg_destroy that work on either
// flavor of JPEG object. These may be more convenient in some places.
/// <summary>
/// Abort processing of a JPEG compression or decompression operation,
/// but don't destroy the object itself.
///
/// Closing a data source or destination, if necessary, is the
/// application's responsibility.
/// </summary>
public void jpeg_abort()
{
/* Reset overall state for possible reuse of object */
if (IsDecompressor)
{
m_global_state = JpegState.DSTATE_START;
/* Try to keep application from accessing now-deleted marker list.
* A bit kludgy to do it here, but this is the most central place.
*/
jpeg_decompress_struct s = this as jpeg_decompress_struct;
if (s != null)
s.m_marker_list = null;
}
else
{
m_global_state = JpegState.CSTATE_START;
}
}
private savable_state m_saved = new savable_state(); /* Other state at start of MCU */
#endregion Fields
#region Constructors
public phuff_entropy_decoder(jpeg_decompress_struct cinfo)
{
m_cinfo = cinfo;
/* Mark derived tables unallocated */
for (int i = 0; i < JpegConstants.NUM_HUFF_TBLS; i++)
m_derived_tbls[i] = null;
/* Create progression status table */
cinfo.m_coef_bits = new int[cinfo.m_num_components][];
for (int i = 0; i < cinfo.m_num_components; i++)
cinfo.m_coef_bits[i] = new int[JpegConstants.DCTSIZE2];
for (int ci = 0; ci < cinfo.m_num_components; ci++)
{
for (int i = 0; i < JpegConstants.DCTSIZE2; i++)
cinfo.m_coef_bits[ci][i] = -1;
}
}
// Skip data in an input stream.
private static void skip_input_data
(ref jpeg_decompress_struct cinfo, Long num_bytes)
{
#if __CSCC__
jpeg_source_mgr *src = cinfo.src;
int num = (int)num_bytes;
if (num > 0)
{
while (num > (int)(src->bytes_in_buffer))
{
num -= (int)(src->bytes_in_buffer);
fill_input_buffer(ref cinfo);
}
src->next_input_byte =
new IntPtr((src->next_input_byte.ToInt64()) + num);
src->bytes_in_buffer =
(size_t)(((int)(src->bytes_in_buffer)) - num);
}
#endif
}
private int m_rows_to_go; /* counts rows remaining in image */
public my_merged_upsampler(jpeg_decompress_struct cinfo)
{
m_cinfo = cinfo;
m_need_context_rows = false;
m_out_row_width = cinfo.m_output_width * cinfo.m_out_color_components;
if (cinfo.m_max_v_samp_factor == 2)
{
m_use_2v_upsample = true;
/* Allocate a spare row buffer */
m_spare_row = new byte[m_out_row_width];
}
else
{
m_use_2v_upsample = false;
}
build_ycc_rgb_table();
}
/// <summary>
/// Skip over an unknown or uninteresting variable-length marker
/// </summary>
private static bool skip_variable(jpeg_decompress_struct cinfo)
{
int length;
if (!cinfo.m_src.GetTwoBytes(out length))
{
return(false);
}
length -= 2;
cinfo.TRACEMS(1, J_MESSAGE_CODE.JTRC_MISC_MARKER, cinfo.m_unread_marker, length);
if (length > 0)
{
cinfo.m_src.skip_input_data(length);
}
return(true);
}
private int m_bytes_read; /* data bytes read so far in marker */
/* Note: cur_marker is not linked into marker_list until it's all read. */
/// <summary>
/// Initialize the marker reader module.
/// This is called only once, when the decompression object is created.
/// </summary>
public jpeg_marker_reader(jpeg_decompress_struct cinfo)
{
m_cinfo = cinfo;
/* Initialize COM/APPn processing.
* By default, we examine and then discard APP0 and APP14,
* but simply discard COM and all other APPn.
*/
m_process_COM = skip_variable;
for (int i = 0; i < 16; i++)
{
m_process_APPn[i] = skip_variable;
m_length_limit_APPn[i] = 0;
}
m_process_APPn[0] = get_interesting_appn;
m_process_APPn[14] = get_interesting_appn;
/* Reset marker processing state */
reset_marker_reader();
}
private int m_bytes_read; /* data bytes read so far in marker */
/* Note: cur_marker is not linked into marker_list until it's all read. */
/// <summary>
/// Initialize the marker reader module.
/// This is called only once, when the decompression object is created.
/// </summary>
public jpeg_marker_reader(jpeg_decompress_struct cinfo)
{
m_cinfo = cinfo;
/* Initialize COM/APPn processing.
* By default, we examine and then discard APP0 and APP14,
* but simply discard COM and all other APPn.
*/
m_process_COM = skip_variable;
for (int i = 0; i < 16; i++)
{
m_process_APPn[i] = skip_variable;
m_length_limit_APPn[i] = 0;
}
m_process_APPn[0] = get_interesting_appn;
m_process_APPn[14] = get_interesting_appn;
/* Reset marker processing state */
reset_marker_reader();
}
/// <summary>
/// Examine first few bytes from an APP14.
/// Take appropriate action if it is an Adobe marker.
/// datalen is # of bytes at data[], remaining is length of rest of marker data.
/// </summary>
private static void examine_app14(jpeg_decompress_struct cinfo, byte[] data, int datalen, int remaining)
{
if (datalen >= APP14_DATA_LEN &&
data[0] == 0x41 &&
data[1] == 0x64 &&
data[2] == 0x6F &&
data[3] == 0x62 &&
data[4] == 0x65)
{
/* Found Adobe APP14 marker */
int version = (data[5] << 8) + data[6];
int flags0 = (data[7] << 8) + data[8];
int flags1 = (data[9] << 8) + data[10];
int transform = data[11];
cinfo.TRACEMS(1, J_MESSAGE_CODE.JTRC_ADOBE, version, flags0, flags1, transform);
cinfo.m_saw_Adobe_marker = true;
cinfo.m_Adobe_transform = (byte)transform;
}
else
{
/* Start of APP14 does not match "Adobe", or too short */
cinfo.TRACEMS(1, J_MESSAGE_CODE.JTRC_APP14, datalen + remaining);
}
}
/// <summary>
/// Save an APPn or COM marker into the marker list
/// </summary>
private static bool save_marker(jpeg_decompress_struct cinfo)
{
jpeg_marker_struct cur_marker = cinfo.m_marker.m_cur_marker;
byte[] data = null;
int length = 0;
int bytes_read;
int data_length;
int dataOffset = 0;
if (cur_marker == null)
{
/* begin reading a marker */
if (!cinfo.m_src.GetTwoBytes(out length))
return false;
length -= 2;
if (length >= 0)
{
/* watch out for bogus length word */
/* figure out how much we want to save */
int limit;
if (cinfo.m_unread_marker == (int)JPEG_MARKER.COM)
limit = cinfo.m_marker.m_length_limit_COM;
else
limit = cinfo.m_marker.m_length_limit_APPn[cinfo.m_unread_marker - (int)JPEG_MARKER.APP0];
if (length < limit)
limit = length;
/* allocate and initialize the marker item */
cur_marker = new jpeg_marker_struct((byte)cinfo.m_unread_marker, length, limit);
/* data area is just beyond the jpeg_marker_struct */
data = cur_marker.Data;
cinfo.m_marker.m_cur_marker = cur_marker;
cinfo.m_marker.m_bytes_read = 0;
bytes_read = 0;
data_length = limit;
}
else
{
/* deal with bogus length word */
bytes_read = data_length = 0;
data = null;
}
}
else
{
/* resume reading a marker */
bytes_read = cinfo.m_marker.m_bytes_read;
data_length = cur_marker.Data.Length;
data = cur_marker.Data;
dataOffset = bytes_read;
}
byte[] tempData = null;
if (data_length != 0)
tempData = new byte[data.Length];
while (bytes_read < data_length)
{
/* move the restart point to here */
cinfo.m_marker.m_bytes_read = bytes_read;
/* If there's not at least one byte in buffer, suspend */
if (!cinfo.m_src.MakeByteAvailable())
return false;
/* Copy bytes with reasonable rapidity */
int read = cinfo.m_src.GetBytes(tempData, data_length - bytes_read);
Buffer.BlockCopy(tempData, 0, data, dataOffset, data_length - bytes_read);
bytes_read += read;
}
/* Done reading what we want to read */
if (cur_marker != null)
{
/* will be null if bogus length word */
/* Add new marker to end of list */
cinfo.m_marker_list.Add(cur_marker);
/* Reset pointer & calc remaining data length */
data = cur_marker.Data;
dataOffset = 0;
length = cur_marker.OriginalLength - data_length;
}
/* Reset to initial state for next marker */
cinfo.m_marker.m_cur_marker = null;
JPEG_MARKER currentMarker = (JPEG_MARKER)cinfo.m_unread_marker;
if (data_length != 0 && (currentMarker == JPEG_MARKER.APP0 || currentMarker == JPEG_MARKER.APP14))
{
tempData = new byte[data.Length];
Buffer.BlockCopy(data, dataOffset, tempData, 0, data.Length - dataOffset);
}
/* Process the marker if interesting; else just make a generic trace msg */
switch ((JPEG_MARKER)cinfo.m_unread_marker)
{
case JPEG_MARKER.APP0:
examine_app0(cinfo, tempData, data_length, length);
break;
case JPEG_MARKER.APP14:
examine_app14(cinfo, tempData, data_length, length);
break;
default:
cinfo.TRACEMS(1, J_MESSAGE_CODE.JTRC_MISC_MARKER, cinfo.m_unread_marker, data_length + length);
break;
}
/* skip any remaining data -- could be lots */
if (length > 0)
cinfo.m_src.skip_input_data(length);
return true;
}
private bool m_on_odd_row; /* flag to remember which row we are on */
/// <summary>
/// Module initialization routine for 1-pass color quantization.
/// </summary>
/// <param name="cinfo">The cinfo.</param>
public my_1pass_cquantizer(jpeg_decompress_struct cinfo)
{
m_cinfo = cinfo;
m_fserrors[0] = null; /* Flag FS workspace not allocated */
m_odither[0] = null; /* Also flag odither arrays not allocated */
/* Make sure my internal arrays won't overflow */
if (cinfo.m_out_color_components > MAX_Q_COMPS)
cinfo.ERREXIT(J_MESSAGE_CODE.JERR_QUANT_COMPONENTS, MAX_Q_COMPS);
/* Make sure colormap indexes can be represented by JSAMPLEs */
if (cinfo.m_desired_number_of_colors > (JpegConstants.MAXJSAMPLE + 1))
cinfo.ERREXIT(J_MESSAGE_CODE.JERR_QUANT_MANY_COLORS, JpegConstants.MAXJSAMPLE + 1);
/* Create the colormap and color index table. */
create_colormap();
create_colorindex();
/* Allocate Floyd-Steinberg workspace now if requested.
* We do this now since it is FAR storage and may affect the memory
* manager's space calculations. If the user changes to FS dither
* mode in a later pass, we will allocate the space then, and will
* possibly overrun the max_memory_to_use setting.
*/
if (cinfo.m_dither_mode == J_DITHER_MODE.JDITHER_FS)
alloc_fs_workspace();
}
private bool m_start_of_file; /* have we gotten any data yet? */
/// <summary>
/// Initialize source - called by jpeg_read_header
/// before any data is actually read.
/// </summary>
public my_source_mgr(jpeg_decompress_struct cinfo)
{
m_cinfo = cinfo;
m_buffer = new byte[INPUT_BUF_SIZE];
}
/// <summary>
/// Install a special processing method for COM or APPn markers.
/// </summary>
public void jpeg_set_marker_processor(int marker_code, jpeg_decompress_struct.jpeg_marker_parser_method routine)
{
if (marker_code == (int)JPEG_MARKER.COM)
m_process_COM = routine;
else if (marker_code >= (int)JPEG_MARKER.APP0 && marker_code <= (int)JPEG_MARKER.APP15)
m_process_APPn[marker_code - (int)JPEG_MARKER.APP0] = routine;
else
m_cinfo.ERREXIT(J_MESSAGE_CODE.JERR_UNKNOWN_MARKER, marker_code);
}
private int m_whichFunny; /* indicates which funny indices set is now in use */
#endregion Fields
#region Constructors
public jpeg_d_main_controller(jpeg_decompress_struct cinfo)
{
m_cinfo = cinfo;
/* Allocate the workspace.
* ngroups is the number of row groups we need.
*/
int ngroups = cinfo.m_min_DCT_scaled_size;
if (cinfo.m_upsample.NeedContextRows())
{
if (cinfo.m_min_DCT_scaled_size < 2) /* unsupported, see comments above */
cinfo.ERREXIT(J_MESSAGE_CODE.JERR_NOTIMPL);
alloc_funny_pointers(); /* Alloc space for xbuffer[] lists */
ngroups = cinfo.m_min_DCT_scaled_size + 2;
}
for (int ci = 0; ci < cinfo.m_num_components; ci++)
{
/* height of a row group of component */
int rgroup = (cinfo.Comp_info[ci].V_samp_factor * cinfo.Comp_info[ci].DCT_scaled_size) / cinfo.m_min_DCT_scaled_size;
m_buffer[ci] = jpeg_common_struct.AllocJpegSamples(
cinfo.Comp_info[ci].Width_in_blocks * cinfo.Comp_info[ci].DCT_scaled_size,
rgroup * ngroups);
}
}
// Skip data in an input stream.
private static void skip_input_data
(ref jpeg_decompress_struct cinfo, Long num_bytes)
{
#if __CSCC__
jpeg_source_mgr *src = cinfo.src;
int num = (int)num_bytes;
if(num > 0)
{
while(num > (int)(src->bytes_in_buffer))
{
num -= (int)(src->bytes_in_buffer);
fill_input_buffer(ref cinfo);
}
src->next_input_byte =
new IntPtr((src->next_input_byte.ToInt64()) + num);
src->bytes_in_buffer =
(size_t)(((int)(src->bytes_in_buffer)) - num);
}
#endif
}
/// <summary>
/// This is the default resync_to_restart method for data source
/// managers to use if they don't have any better approach.
/// </summary>
/// <param name="cinfo">An instance of <see cref="jpeg_decompress_struct"/></param>
/// <param name="desired">The desired</param>
/// <returns><c>false</c> if suspension is required.</returns>
/// <remarks>That method assumes that no backtracking is possible.
/// Some data source managers may be able to back up, or may have
/// additional knowledge about the data which permits a more
/// intelligent recovery strategy; such managers would
/// presumably supply their own resync method.<br/><br/>
///
/// read_restart_marker calls resync_to_restart if it finds a marker other than
/// the restart marker it was expecting. (This code is *not* used unless
/// a nonzero restart interval has been declared.) cinfo.unread_marker is
/// the marker code actually found (might be anything, except 0 or FF).
/// The desired restart marker number (0..7) is passed as a parameter.<br/><br/>
///
/// This routine is supposed to apply whatever error recovery strategy seems
/// appropriate in order to position the input stream to the next data segment.
/// Note that cinfo.unread_marker is treated as a marker appearing before
/// the current data-source input point; usually it should be reset to zero
/// before returning.<br/><br/>
///
/// This implementation is substantially constrained by wanting to treat the
/// input as a data stream; this means we can't back up. Therefore, we have
/// only the following actions to work with:<br/>
/// 1. Simply discard the marker and let the entropy decoder resume at next
/// byte of file.<br/>
/// 2. Read forward until we find another marker, discarding intervening
/// data. (In theory we could look ahead within the current bufferload,
/// without having to discard data if we don't find the desired marker.
/// This idea is not implemented here, in part because it makes behavior
/// dependent on buffer size and chance buffer-boundary positions.)<br/>
/// 3. Leave the marker unread (by failing to zero cinfo.unread_marker).
/// This will cause the entropy decoder to process an empty data segment,
/// inserting dummy zeroes, and then we will reprocess the marker.<br/>
///
/// #2 is appropriate if we think the desired marker lies ahead, while #3 is
/// appropriate if the found marker is a future restart marker (indicating
/// that we have missed the desired restart marker, probably because it got
/// corrupted).<br/>
/// We apply #2 or #3 if the found marker is a restart marker no more than
/// two counts behind or ahead of the expected one. We also apply #2 if the
/// found marker is not a legal JPEG marker code (it's certainly bogus data).
/// If the found marker is a restart marker more than 2 counts away, we do #1
/// (too much risk that the marker is erroneous; with luck we will be able to
/// resync at some future point).<br/>
/// For any valid non-restart JPEG marker, we apply #3. This keeps us from
/// overrunning the end of a scan. An implementation limited to single-scan
/// files might find it better to apply #2 for markers other than EOI, since
/// any other marker would have to be bogus data in that case.</remarks>
public virtual bool resync_to_restart(jpeg_decompress_struct cinfo, int desired)
{
/* Always put up a warning. */
cinfo.WARNMS(J_MESSAGE_CODE.JWRN_MUST_RESYNC, cinfo.m_unread_marker, desired);
/* Outer loop handles repeated decision after scanning forward. */
int action = 1;
for ( ; ; )
{
if (cinfo.m_unread_marker < (int)JPEG_MARKER.SOF0)
{
/* invalid marker */
action = 2;
}
else if (cinfo.m_unread_marker < (int)JPEG_MARKER.RST0 ||
cinfo.m_unread_marker > (int)JPEG_MARKER.RST7)
{
/* valid non-restart marker */
action = 3;
}
else
{
if (cinfo.m_unread_marker == ((int)JPEG_MARKER.RST0 + ((desired + 1) & 7))
|| cinfo.m_unread_marker == ((int)JPEG_MARKER.RST0 + ((desired + 2) & 7)))
{
/* one of the next two expected restarts */
action = 3;
}
else if (cinfo.m_unread_marker == ((int)JPEG_MARKER.RST0 + ((desired - 1) & 7)) ||
cinfo.m_unread_marker == ((int)JPEG_MARKER.RST0 + ((desired - 2) & 7)))
{
/* a prior restart, so advance */
action = 2;
}
else
{
/* desired restart or too far away */
action = 1;
}
}
cinfo.TRACEMS(4, J_MESSAGE_CODE.JTRC_RECOVERY_ACTION, cinfo.m_unread_marker, action);
switch (action)
{
case 1:
/* Discard marker and let entropy decoder resume processing. */
cinfo.m_unread_marker = 0;
return true;
case 2:
/* Scan to the next marker, and repeat the decision loop. */
if (!cinfo.m_marker.next_marker())
return false;
break;
case 3:
/* Return without advancing past this marker. */
/* Entropy decoder will be forced to process an empty segment. */
return true;
}
}
}
public jpeg_decomp_master(jpeg_decompress_struct cinfo)
{
m_cinfo = cinfo;
master_selection();
}
private int[] rgb_y_tab; /* => table for RGB to Y conversion */
/// <summary>
/// Module initialization routine for output colorspace conversion.
/// </summary>
public jpeg_color_deconverter(jpeg_decompress_struct cinfo)
{
m_cinfo = cinfo;
/* Make sure num_components agrees with jpeg_color_space */
switch (cinfo.m_jpeg_color_space)
{
case J_COLOR_SPACE.JCS_GRAYSCALE:
if (cinfo.m_num_components != 1)
cinfo.ERREXIT(J_MESSAGE_CODE.JERR_BAD_J_COLORSPACE);
break;
case J_COLOR_SPACE.JCS_RGB:
case J_COLOR_SPACE.JCS_YCbCr:
case J_COLOR_SPACE.JCS_BG_RGB:
case J_COLOR_SPACE.JCS_BG_YCC:
if (cinfo.m_num_components != 3)
cinfo.ERREXIT(J_MESSAGE_CODE.JERR_BAD_J_COLORSPACE);
break;
case J_COLOR_SPACE.JCS_CMYK:
case J_COLOR_SPACE.JCS_YCCK:
if (cinfo.m_num_components != 4)
cinfo.ERREXIT(J_MESSAGE_CODE.JERR_BAD_J_COLORSPACE);
break;
case J_COLOR_SPACE.JCS_NCHANNEL:
if (cinfo.m_num_components < 1)
cinfo.ERREXIT(J_MESSAGE_CODE.JERR_BAD_J_COLORSPACE);
break;
default:
/* JCS_UNKNOWN can be anything */
if (cinfo.m_num_components < 1)
cinfo.ERREXIT(J_MESSAGE_CODE.JERR_BAD_J_COLORSPACE);
break;
}
/* Support color transform only for RGB colorspaces */
if (cinfo.color_transform != J_COLOR_TRANSFORM.JCT_NONE &&
cinfo.m_jpeg_color_space != J_COLOR_SPACE.JCS_RGB &&
cinfo.m_jpeg_color_space != J_COLOR_SPACE.JCS_BG_RGB)
{
cinfo.ERREXIT(J_MESSAGE_CODE.JERR_CONVERSION_NOTIMPL);
}
/* Set out_color_components and conversion method based on requested space.
* Also clear the component_needed flags for any unused components,
* so that earlier pipeline stages can avoid useless computation.
*/
switch (cinfo.m_out_color_space)
{
case J_COLOR_SPACE.JCS_GRAYSCALE:
cinfo.m_out_color_components = 1;
switch (cinfo.m_jpeg_color_space)
{
case J_COLOR_SPACE.JCS_GRAYSCALE:
case J_COLOR_SPACE.JCS_YCbCr:
case J_COLOR_SPACE.JCS_BG_YCC:
m_converter = grayscale_convert;
/* For color->grayscale conversion, only the Y (0) component is needed */
for (int ci = 1; ci < cinfo.m_num_components; ci++)
cinfo.Comp_info[ci].component_needed = false;
break;
case J_COLOR_SPACE.JCS_RGB:
switch (cinfo.color_transform)
{
case J_COLOR_TRANSFORM.JCT_NONE:
m_converter = rgb_gray_convert;
break;
case J_COLOR_TRANSFORM.JCT_SUBTRACT_GREEN:
m_converter = rgb1_gray_convert;
break;
default:
cinfo.ERREXIT(J_MESSAGE_CODE.JERR_CONVERSION_NOTIMPL);
break;
}
build_rgb_y_table();
break;
default:
cinfo.ERREXIT(J_MESSAGE_CODE.JERR_CONVERSION_NOTIMPL);
break;
}
break;
case J_COLOR_SPACE.JCS_RGB:
cinfo.m_out_color_components = JpegConstants.RGB_PIXELSIZE;
switch (cinfo.m_jpeg_color_space)
{
case J_COLOR_SPACE.JCS_GRAYSCALE:
m_converter = gray_rgb_convert;
break;
case J_COLOR_SPACE.JCS_YCbCr:
m_converter = ycc_rgb_convert;
build_ycc_rgb_table();
break;
case J_COLOR_SPACE.JCS_BG_YCC:
m_converter = ycc_rgb_convert;
build_bg_ycc_rgb_table();
break;
case J_COLOR_SPACE.JCS_RGB:
switch (cinfo.color_transform)
{
case J_COLOR_TRANSFORM.JCT_NONE:
m_converter = rgb_convert;
break;
case J_COLOR_TRANSFORM.JCT_SUBTRACT_GREEN:
m_converter = rgb1_rgb_convert;
break;
default:
cinfo.ERREXIT(J_MESSAGE_CODE.JERR_CONVERSION_NOTIMPL);
break;
}
break;
case J_COLOR_SPACE.JCS_CMYK:
m_converter = cmyk_rgb_convert;
break;
case J_COLOR_SPACE.JCS_YCCK:
m_converter = ycck_rgb_convert;
build_ycc_rgb_table();
break;
default:
cinfo.ERREXIT(J_MESSAGE_CODE.JERR_CONVERSION_NOTIMPL);
break;
}
break;
case J_COLOR_SPACE.JCS_BG_RGB:
cinfo.m_out_color_components = JpegConstants.RGB_PIXELSIZE;
if (cinfo.m_jpeg_color_space == J_COLOR_SPACE.JCS_BG_RGB)
{
switch (cinfo.color_transform)
{
case J_COLOR_TRANSFORM.JCT_NONE:
m_converter = rgb_convert;
break;
case J_COLOR_TRANSFORM.JCT_SUBTRACT_GREEN:
m_converter = rgb1_rgb_convert;
break;
default:
cinfo.ERREXIT(J_MESSAGE_CODE.JERR_CONVERSION_NOTIMPL);
break;
}
}
else
{
cinfo.ERREXIT(J_MESSAGE_CODE.JERR_CONVERSION_NOTIMPL);
}
break;
case J_COLOR_SPACE.JCS_CMYK:
cinfo.m_out_color_components = 4;
switch (cinfo.m_jpeg_color_space)
{
case J_COLOR_SPACE.JCS_YCCK:
m_converter = ycck_cmyk_convert;
build_ycc_rgb_table();
break;
case J_COLOR_SPACE.JCS_CMYK:
m_converter = null_convert;
break;
default:
cinfo.ERREXIT(J_MESSAGE_CODE.JERR_CONVERSION_NOTIMPL);
break;
}
break;
case J_COLOR_SPACE.JCS_NCHANNEL:
if (cinfo.m_jpeg_color_space == J_COLOR_SPACE.JCS_NCHANNEL)
m_converter = null_convert;
else
cinfo.ERREXIT(J_MESSAGE_CODE.JERR_CONVERSION_NOTIMPL);
break;
default:
/* Permit null conversion to same output space */
if (cinfo.m_out_color_space == cinfo.m_jpeg_color_space)
{
cinfo.m_out_color_components = cinfo.m_num_components;
m_converter = null_convert;
}
else
{
/* unsupported non-null conversion */
cinfo.ERREXIT(J_MESSAGE_CODE.JERR_CONVERSION_NOTIMPL);
}
break;
}
if (cinfo.m_quantize_colors)
cinfo.m_output_components = 1; /* single colormapped output component */
else
cinfo.m_output_components = cinfo.m_out_color_components;
}
/*
* Routines for processing APPn and COM markers.
* These are either saved in memory or discarded, per application request.
* APP0 and APP14 are specially checked to see if they are
* JFIF and Adobe markers, respectively.
*/
/// <summary>
/// Examine first few bytes from an APP0.
/// Take appropriate action if it is a JFIF marker.
/// datalen is # of bytes at data[], remaining is length of rest of marker data.
/// </summary>
private static void examine_app0(jpeg_decompress_struct cinfo, byte[] data, int datalen, int remaining)
{
int totallen = datalen + remaining;
if (datalen >= APP0_DATA_LEN &&
data[0] == 0x4A &&
data[1] == 0x46 &&
data[2] == 0x49 &&
data[3] == 0x46 &&
data[4] == 0)
{
/* Found JFIF APP0 marker: save info */
cinfo.m_saw_JFIF_marker = true;
cinfo.m_JFIF_major_version = data[5];
cinfo.m_JFIF_minor_version = data[6];
cinfo.m_density_unit = (DensityUnit)data[7];
cinfo.m_X_density = (short)((data[8] << 8) + data[9]);
cinfo.m_Y_density = (short)((data[10] << 8) + data[11]);
/* Check version.
* Major version must be 1, anything else signals an incompatible change.
* (We used to treat this as an error, but now it's a nonfatal warning,
* because some bozo at Hijaak couldn't read the spec.)
* Minor version should be 0..2, but process anyway if newer.
*/
if (cinfo.m_JFIF_major_version != 1)
cinfo.WARNMS(J_MESSAGE_CODE.JWRN_JFIF_MAJOR, cinfo.m_JFIF_major_version, cinfo.m_JFIF_minor_version);
/* Generate trace messages */
cinfo.TRACEMS(1, J_MESSAGE_CODE.JTRC_JFIF, cinfo.m_JFIF_major_version, cinfo.m_JFIF_minor_version, cinfo.m_X_density,
cinfo.m_Y_density, cinfo.m_density_unit);
/* Validate thumbnail dimensions and issue appropriate messages */
if ((data[12] | data[13]) != 0)
cinfo.TRACEMS(1, J_MESSAGE_CODE.JTRC_JFIF_THUMBNAIL, data[12], data[13]);
totallen -= APP0_DATA_LEN;
if (totallen != ((int)data[12] * (int)data[13] * 3))
cinfo.TRACEMS(1, J_MESSAGE_CODE.JTRC_JFIF_BADTHUMBNAILSIZE, totallen);
}
else if (datalen >= 6 && data[0] == 0x4A && data[1] == 0x46 && data[2] == 0x58 && data[3] == 0x58 && data[4] == 0)
{
/* Found JFIF "JFXX" extension APP0 marker */
/* The library doesn't actually do anything with these,
* but we try to produce a helpful trace message.
*/
switch (data[5])
{
case 0x10:
cinfo.TRACEMS(1, J_MESSAGE_CODE.JTRC_THUMB_JPEG, totallen);
break;
case 0x11:
cinfo.TRACEMS(1, J_MESSAGE_CODE.JTRC_THUMB_PALETTE, totallen);
break;
case 0x13:
cinfo.TRACEMS(1, J_MESSAGE_CODE.JTRC_THUMB_RGB, totallen);
break;
default:
cinfo.TRACEMS(1, J_MESSAGE_CODE.JTRC_JFIF_EXTENSION, data[5], totallen);
break;
}
}
else
{
/* Start of APP0 does not match "JFIF" or "JFXX", or too short */
cinfo.TRACEMS(1, J_MESSAGE_CODE.JTRC_APP0, totallen);
}
}
// Convert a stream into a source manager.
public static void StreamToSourceManager
(ref jpeg_decompress_struct cinfo, Stream stream,
byte[] prime, int primeLen)
{
// Allocate a state structure and store it in "cinfo".
IntPtr buf = Marshal.AllocHGlobal(4096);
StreamState state = new StreamState();
state.buf = buf;
state.buffer = new byte [4096];
state.stream = stream;
cinfo.client_data = (IntPtr)(GCHandle.Alloc(state));
// We prime the input buffer with the JPEG magic number
// if some higher-level process has already read it.
int len;
if(prime != null)
{
len = primeLen;
Marshal.Copy(prime, 0, buf, len);
}
else
{
len = 0;
}
// Create the managed version of "jpeg_source_mgr".
jpeg_source_mgr mgr = new jpeg_source_mgr();
mgr.next_input_byte = buf;
mgr.bytes_in_buffer = (size_t)len;
mgr.init_source = new init_source_type(init_source);
mgr.fill_input_buffer =
new fill_input_buffer_type(fill_input_buffer);
mgr.skip_input_data =
new skip_input_data_type(skip_input_data);
mgr.resync_to_restart =
new resync_to_restart_type(jpeg_resync_to_restart);
mgr.term_source =
new term_source_type(term_source);
// Convert it into the unmanaged version and store it.
#if __CSCC__
IntPtr umgr = Marshal.AllocHGlobal(sizeof(jpeg_source_mgr));
Marshal.StructureToPtr(mgr, umgr, false);
cinfo.src = (jpeg_source_mgr *)umgr;
#endif
}
// Free a source manager.
public static void FreeSourceManager(ref jpeg_decompress_struct cinfo)
{
GCHandle handle = (GCHandle)(cinfo.client_data);
StreamState state = (StreamState)(handle.Target);
Marshal.FreeHGlobal(state.buf);
handle.Free();
Marshal.FreeHGlobal((IntPtr)(cinfo.src));
cinfo.client_data = IntPtr.Zero;
cinfo.src = null;
}
public huff_entropy_decoder(jpeg_decompress_struct cinfo)
{
m_cinfo = cinfo;
finish_pass = finish_pass_huff;
if (m_cinfo.m_progressive_mode)
{
/* Create progression status table */
cinfo.m_coef_bits = new int[cinfo.m_num_components][];
for (int i = 0; i < cinfo.m_num_components; i++)
cinfo.m_coef_bits[i] = new int[JpegConstants.DCTSIZE2];
for (int ci = 0; ci < cinfo.m_num_components; ci++)
{
for (int i = 0; i < JpegConstants.DCTSIZE2; i++)
cinfo.m_coef_bits[ci][i] = -1;
}
/* Mark derived tables unallocated */
for (int i = 0; i < JpegConstants.NUM_HUFF_TBLS; i++)
{
derived_tbls[i] = null;
}
}
else
{
/* Mark tables unallocated */
for (int i = 0; i < JpegConstants.NUM_HUFF_TBLS; i++)
{
m_dc_derived_tbls[i] = null;
m_ac_derived_tbls[i] = null;
}
}
}
/// <summary>
/// Skip over an unknown or uninteresting variable-length marker
/// </summary>
private static bool skip_variable(jpeg_decompress_struct cinfo)
{
int length;
if (!cinfo.m_src.GetTwoBytes(out length))
return false;
length -= 2;
cinfo.TRACEMS(1, J_MESSAGE_CODE.JTRC_MISC_MARKER, cinfo.m_unread_marker, length);
if (length > 0)
cinfo.m_src.skip_input_data(length);
return true;
}
public my_upsampler(jpeg_decompress_struct cinfo)
{
m_cinfo = cinfo;
m_need_context_rows = false; /* until we find out differently */
if (cinfo.m_CCIR601_sampling) /* this isn't supported */
cinfo.ERREXIT(J_MESSAGE_CODE.JERR_CCIR601_NOTIMPL);
/* jpeg_d_main_controller doesn't support context rows when min_DCT_scaled_size = 1,
* so don't ask for it.
*/
bool do_fancy = cinfo.m_do_fancy_upsampling && cinfo.m_min_DCT_scaled_size > 1;
/* Verify we can handle the sampling factors, select per-component methods,
* and create storage as needed.
*/
for (int ci = 0; ci < cinfo.m_num_components; ci++)
{
jpeg_component_info componentInfo = cinfo.Comp_info[ci];
/* Compute size of an "input group" after IDCT scaling. This many samples
* are to be converted to max_h_samp_factor * max_v_samp_factor pixels.
*/
int h_in_group = (componentInfo.H_samp_factor * componentInfo.DCT_scaled_size) / cinfo.m_min_DCT_scaled_size;
int v_in_group = (componentInfo.V_samp_factor * componentInfo.DCT_scaled_size) / cinfo.m_min_DCT_scaled_size;
int h_out_group = cinfo.m_max_h_samp_factor;
int v_out_group = cinfo.m_max_v_samp_factor;
/* save for use later */
m_rowgroup_height[ci] = v_in_group;
bool need_buffer = true;
if (!componentInfo.component_needed)
{
/* Don't bother to upsample an uninteresting component. */
m_upsampleMethods[ci] = ComponentUpsampler.noop_upsampler;
need_buffer = false;
}
else if (h_in_group == h_out_group && v_in_group == v_out_group)
{
/* Fullsize components can be processed without any work. */
m_upsampleMethods[ci] = ComponentUpsampler.fullsize_upsampler;
need_buffer = false;
}
else if (h_in_group * 2 == h_out_group && v_in_group == v_out_group)
{
/* Special cases for 2h1v upsampling */
if (do_fancy && componentInfo.downsampled_width > 2)
m_upsampleMethods[ci] = ComponentUpsampler.h2v1_fancy_upsampler;
else
m_upsampleMethods[ci] = ComponentUpsampler.h2v1_upsampler;
}
else if (h_in_group * 2 == h_out_group && v_in_group * 2 == v_out_group)
{
/* Special cases for 2h2v upsampling */
if (do_fancy && componentInfo.downsampled_width > 2)
{
m_upsampleMethods[ci] = ComponentUpsampler.h2v2_fancy_upsampler;
m_need_context_rows = true;
}
else
{
m_upsampleMethods[ci] = ComponentUpsampler.h2v2_upsampler;
}
}
else if ((h_out_group % h_in_group) == 0 && (v_out_group % v_in_group) == 0)
{
/* Generic integral-factors upsampling method */
m_upsampleMethods[ci] = ComponentUpsampler.int_upsampler;
m_h_expand[ci] = (byte) (h_out_group / h_in_group);
m_v_expand[ci] = (byte) (v_out_group / v_in_group);
}
else
cinfo.ERREXIT(J_MESSAGE_CODE.JERR_FRACT_SAMPLE_NOTIMPL);
if (need_buffer)
{
ComponentBuffer cb = new ComponentBuffer();
cb.SetBuffer(jpeg_common_struct.AllocJpegSamples(JpegUtils.jround_up(cinfo.m_output_width,
cinfo.m_max_h_samp_factor), cinfo.m_max_v_samp_factor), null, 0);
m_color_buf[ci] = cb;
}
}
}
/// <summary>
/// Process an APP0 or APP14 marker without saving it
/// </summary>
private static bool get_interesting_appn(jpeg_decompress_struct cinfo)
{
int length;
if (!cinfo.m_src.GetTwoBytes(out length))
return false;
length -= 2;
/* get the interesting part of the marker data */
int numtoread = 0;
if (length >= APPN_DATA_LEN)
numtoread = APPN_DATA_LEN;
else if (length > 0)
numtoread = length;
byte[] b = new byte[APPN_DATA_LEN];
for (int i = 0; i < numtoread; i++)
{
int temp = 0;
if (!cinfo.m_src.GetByte(out temp))
return false;
b[i] = (byte) temp;
}
length -= numtoread;
/* process it */
switch ((JPEG_MARKER)cinfo.m_unread_marker)
{
case JPEG_MARKER.APP0:
examine_app0(cinfo, b, numtoread, length);
break;
case JPEG_MARKER.APP14:
examine_app14(cinfo, b, numtoread, length);
break;
default:
/* can't get here unless jpeg_save_markers chooses wrong processor */
cinfo.ERREXIT(J_MESSAGE_CODE.JERR_UNKNOWN_MARKER, cinfo.m_unread_marker);
break;
}
/* skip any remaining data -- could be lots */
if (length > 0)
cinfo.m_src.skip_input_data(length);
return true;
}
private int[] m_Cb_g_tab; /* => table for Cb to G conversion */
/// <summary>
/// Module initialization routine for output colorspace conversion.
/// </summary>
public jpeg_color_deconverter(jpeg_decompress_struct cinfo)
{
m_cinfo = cinfo;
/* Make sure num_components agrees with jpeg_color_space */
switch (cinfo.m_jpeg_color_space)
{
case J_COLOR_SPACE.JCS_GRAYSCALE:
if (cinfo.m_num_components != 1)
cinfo.ERREXIT(J_MESSAGE_CODE.JERR_BAD_J_COLORSPACE);
break;
case J_COLOR_SPACE.JCS_RGB:
case J_COLOR_SPACE.JCS_YCbCr:
if (cinfo.m_num_components != 3)
cinfo.ERREXIT(J_MESSAGE_CODE.JERR_BAD_J_COLORSPACE);
break;
case J_COLOR_SPACE.JCS_CMYK:
case J_COLOR_SPACE.JCS_YCCK:
if (cinfo.m_num_components != 4)
cinfo.ERREXIT(J_MESSAGE_CODE.JERR_BAD_J_COLORSPACE);
break;
default:
/* JCS_UNKNOWN can be anything */
if (cinfo.m_num_components < 1)
cinfo.ERREXIT(J_MESSAGE_CODE.JERR_BAD_J_COLORSPACE);
break;
}
/* Set out_color_components and conversion method based on requested space.
* Also clear the component_needed flags for any unused components,
* so that earlier pipeline stages can avoid useless computation.
*/
switch (cinfo.m_out_color_space)
{
case J_COLOR_SPACE.JCS_GRAYSCALE:
cinfo.m_out_color_components = 1;
if (cinfo.m_jpeg_color_space == J_COLOR_SPACE.JCS_GRAYSCALE || cinfo.m_jpeg_color_space == J_COLOR_SPACE.JCS_YCbCr)
{
m_converter = ColorConverter.grayscale_converter;
/* For color->grayscale conversion, only the Y (0) component is needed */
for (int ci = 1; ci < cinfo.m_num_components; ci++)
cinfo.Comp_info[ci].component_needed = false;
}
else
cinfo.ERREXIT(J_MESSAGE_CODE.JERR_CONVERSION_NOTIMPL);
break;
case J_COLOR_SPACE.JCS_RGB:
cinfo.m_out_color_components = JpegConstants.RGB_PIXELSIZE;
if (cinfo.m_jpeg_color_space == J_COLOR_SPACE.JCS_YCbCr)
{
m_converter = ColorConverter.ycc_rgb_converter;
build_ycc_rgb_table();
}
else if (cinfo.m_jpeg_color_space == J_COLOR_SPACE.JCS_GRAYSCALE)
m_converter = ColorConverter.gray_rgb_converter;
else if (cinfo.m_jpeg_color_space == J_COLOR_SPACE.JCS_RGB)
m_converter = ColorConverter.null_converter;
else
cinfo.ERREXIT(J_MESSAGE_CODE.JERR_CONVERSION_NOTIMPL);
break;
case J_COLOR_SPACE.JCS_CMYK:
cinfo.m_out_color_components = 4;
if (cinfo.m_jpeg_color_space == J_COLOR_SPACE.JCS_YCCK)
{
m_converter = ColorConverter.ycck_cmyk_converter;
build_ycc_rgb_table();
}
else if (cinfo.m_jpeg_color_space == J_COLOR_SPACE.JCS_CMYK)
m_converter = ColorConverter.null_converter;
else
cinfo.ERREXIT(J_MESSAGE_CODE.JERR_CONVERSION_NOTIMPL);
break;
default:
/* Permit null conversion to same output space */
if (cinfo.m_out_color_space == cinfo.m_jpeg_color_space)
{
cinfo.m_out_color_components = cinfo.m_num_components;
m_converter = ColorConverter.null_converter;
}
else
{
/* unsupported non-null conversion */
cinfo.ERREXIT(J_MESSAGE_CODE.JERR_CONVERSION_NOTIMPL);
}
break;
}
if (cinfo.m_quantize_colors)
cinfo.m_output_components = 1; /* single colormapped output component */
else
cinfo.m_output_components = cinfo.m_out_color_components;
}
/// <summary>
/// Examine first few bytes from an APP14.
/// Take appropriate action if it is an Adobe marker.
/// datalen is # of bytes at data[], remaining is length of rest of marker data.
/// </summary>
private static void examine_app14(jpeg_decompress_struct cinfo, byte[] data, int datalen, int remaining)
{
if (datalen >= APP14_DATA_LEN &&
data[0] == 0x41 &&
data[1] == 0x64 &&
data[2] == 0x6F &&
data[3] == 0x62 &&
data[4] == 0x65)
{
/* Found Adobe APP14 marker */
int version = (data[5] << 8) + data[6];
int flags0 = (data[7] << 8) + data[8];
int flags1 = (data[9] << 8) + data[10];
int transform = data[11];
cinfo.TRACEMS(1, J_MESSAGE_CODE.JTRC_ADOBE, version, flags0, flags1, transform);
cinfo.m_saw_Adobe_marker = true;
cinfo.m_Adobe_transform = (byte) transform;
}
else
{
/* Start of APP14 does not match "Adobe", or too short */
cinfo.TRACEMS(1, J_MESSAGE_CODE.JTRC_APP14, datalen + remaining);
}
}
// Terminate an input source.
private static void term_source(ref jpeg_decompress_struct cinfo)
{
// Nothing to do here.
}
// Fill an input buffer from a stream.
private static Int fill_input_buffer(ref jpeg_decompress_struct cinfo)
{
int len;
StreamState state = GetStreamState(ref cinfo);
if(!(state.sawEOF))
{
len = state.stream.Read
(state.buffer, 0, state.buffer.Length);
if(len > 0)
{
Marshal.Copy(state.buffer, 0, state.buf, len);
cinfo.src->next_input_byte = state.buf;
cinfo.src->bytes_in_buffer = (size_t)len;
return (Int)1;
}
state.sawEOF = true;
}
// Insert an EOI marker to indicate end of stream to "libjpeg".
Marshal.WriteByte(state.buf, 0, (byte)0xFF);
Marshal.WriteByte(state.buf, 1, (byte)0xD9);
cinfo.src->next_input_byte = state.buf;
cinfo.src->bytes_in_buffer = (size_t)2;
return (Int)1;
}
private int[] m_error_limiter; /* table for clamping the applied error */
/// <summary>
/// Module initialization routine for 2-pass color quantization.
/// </summary>
public my_2pass_cquantizer(jpeg_decompress_struct cinfo)
{
m_cinfo = cinfo;
/* Make sure jdmaster didn't give me a case I can't handle */
if (cinfo.m_out_color_components != 3)
cinfo.ERREXIT(J_MESSAGE_CODE.JERR_NOTIMPL);
/* Allocate the histogram/inverse colormap storage */
m_histogram = new ushort[HIST_C0_ELEMS][];
for (int i = 0; i < HIST_C0_ELEMS; i++)
m_histogram[i] = new ushort[HIST_C1_ELEMS * HIST_C2_ELEMS];
m_needs_zeroed = true; /* histogram is garbage now */
/* Allocate storage for the completed colormap, if required.
* We do this now since it is FAR storage and may affect
* the memory manager's space calculations.
*/
if (cinfo.m_enable_2pass_quant)
{
/* Make sure color count is acceptable */
int desired_local = cinfo.m_desired_number_of_colors;
/* Lower bound on # of colors ... somewhat arbitrary as long as > 0 */
if (desired_local < 8)
cinfo.ERREXIT(J_MESSAGE_CODE.JERR_QUANT_FEW_COLORS, 8);
/* Make sure colormap indexes can be represented by JSAMPLEs */
if (desired_local > MAXNUMCOLORS)
cinfo.ERREXIT(J_MESSAGE_CODE.JERR_QUANT_MANY_COLORS, MAXNUMCOLORS);
m_sv_colormap = jpeg_common_struct.AllocJpegSamples(desired_local, 3);
m_desired = desired_local;
}
/* Only F-S dithering or no dithering is supported. */
/* If user asks for ordered dither, give him F-S. */
if (cinfo.m_dither_mode != J_DITHER_MODE.JDITHER_NONE)
cinfo.m_dither_mode = J_DITHER_MODE.JDITHER_FS;
/* Allocate Floyd-Steinberg workspace if necessary.
* This isn't really needed until pass 2, but again it is FAR storage.
* Although we will cope with a later change in dither_mode,
* we do not promise to honor max_memory_to_use if dither_mode changes.
*/
if (cinfo.m_dither_mode == J_DITHER_MODE.JDITHER_FS)
{
m_fserrors = new short[(cinfo.m_output_width + 2) * 3];
/* Might as well create the error-limiting table too. */
init_error_limit();
}
}
public arith_entropy_decoder(jpeg_decompress_struct cinfo)
{
cinfo.ERREXIT(J_MESSAGE_CODE.JERR_NOTIMPL);
}
public jpeg_inverse_dct(jpeg_decompress_struct cinfo)
{
m_cinfo = cinfo;
m_dctTables = new multiplier_table[cinfo.m_num_components];
for (int ci = 0; ci < cinfo.m_num_components; ci++)
{
/* Allocate and pre-zero a multiplier table for each component */
m_dctTables[ci] = new multiplier_table();
/* Mark multiplier table not yet set up for any method */
m_cur_method[ci] = -1;
}
}
