public override bool Init()
{
Debug.Assert(m_scheme == Compression.JPEG);
/*
* Merge codec-specific tag information and override parent get/set
* field methods.
*/
m_tif.MergeFieldInfo(jpegFieldInfo, jpegFieldInfo.Length);
/*
* Allocate state block so tag methods have storage to record values.
*/
m_compression = null;
m_decompression = null;
m_photometric = 0;
m_h_sampling = 0;
m_v_sampling = 0;
m_bytesperline = 0;
m_scancount = 0;
m_samplesperclump = 0;
m_recvtime = 0;
m_parentTagMethods = m_tif.m_tagmethods;
m_tif.m_tagmethods = m_tagMethods;
/* Default values for codec-specific fields */
m_jpegtables = null;
m_jpegtables_length = 0;
m_jpegquality = 75; /* Default IJG quality */
m_jpegcolormode = JpegColorMode.RGB;
m_jpegtablesmode = JpegTablesMode.Quant | JpegTablesMode.Huff;
m_recvparams = 0;
m_subaddress = null;
m_faxdcs = null;
m_ycbcrsampling_fetched = false;
m_rawDecode = false;
m_rawEncode = false;
m_tif.m_flags |= TiffFlags.NoBitRev; // no bit reversal, please
m_cinfo_initialized = false;
/*
** Create a JPEGTables field if no directory has yet been created.
** We do this just to ensure that sufficient space is reserved for
** the JPEGTables field. It will be properly created the right
** size later.
*/
if (m_tif.m_diroff == 0)
{
const int SIZE_OF_JPEGTABLES = 2000;
// The following line assumes incorrectly that all JPEG-in-TIFF
// files will have a JpegTables tag generated and causes
// null-filled JpegTables tags to be written when the JPEG data
// is placed with WriteRawStrip. The field bit should be
// set, anyway, later when actual JpegTables header is
// generated, so removing it here hopefully is harmless.
//
// m_tif.setFieldBit(FIELD_JPEGTABLES);
//
m_jpegtables_length = SIZE_OF_JPEGTABLES;
m_jpegtables = new byte[m_jpegtables_length];
}
/*
* Mark the YCBCRSAMPLES as present even if it is not
* see: JPEGFixupTestSubsampling().
*/
m_tif.setFieldBit(FieldBit.YCbCrSubsampling);
return true;
}
private void cleanState()
{
m_compression = null;
m_decompression = null;
m_common = null;
m_h_sampling = 0;
m_v_sampling = 0;
m_jpegtables = null;
m_jpegtables_length = 0;
m_jpegquality = 0;
m_jpegcolormode = 0;
m_jpegtablesmode = 0;
m_ycbcrsampling_fetched = false;
m_recvparams = 0;
m_subaddress = null;
m_recvtime = 0;
m_faxdcs = null;
m_rawDecode = false;
m_rawEncode = false;
m_cinfo_initialized = false;
m_err = null;
m_photometric = 0;
m_bytesperline = 0;
m_ds_buffer = new byte[JpegConstants.MAX_COMPONENTS][][];
m_scancount = 0;
m_samplesperclump = 0;
}
