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opencv/modules/imgcodecs/src/grfmt_jpeg.cpp

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/*M///////////////////////////////////////////////////////////////////////////////////////
//
// IMPORTANT: READ BEFORE DOWNLOADING, COPYING, INSTALLING OR USING.
//
// By downloading, copying, installing or using the software you agree to this license.
// If you do not agree to this license, do not download, install,
// copy or use the software.
//
//
// Intel License Agreement
// For Open Source Computer Vision Library
//
// Copyright (C) 2000, Intel Corporation, all rights reserved.
// Third party copyrights are property of their respective owners.
//
// Redistribution and use in source and binary forms, with or without modification,
// are permitted provided that the following conditions are met:
//
// * Redistribution's of source code must retain the above copyright notice,
// this list of conditions and the following disclaimer.
//
// * Redistribution's in binary form must reproduce the above copyright notice,
// this list of conditions and the following disclaimer in the documentation
// and/or other materials provided with the distribution.
//
// * The name of Intel Corporation may not be used to endorse or promote products
// derived from this software without specific prior written permission.
//
// This software is provided by the copyright holders and contributors "as is" and
// any express or implied warranties, including, but not limited to, the implied
// warranties of merchantability and fitness for a particular purpose are disclaimed.
// In no event shall the Intel Corporation or contributors be liable for any direct,
// indirect, incidental, special, exemplary, or consequential damages
// (including, but not limited to, procurement of substitute goods or services;
// loss of use, data, or profits; or business interruption) however caused
// and on any theory of liability, whether in contract, strict liability,
// or tort (including negligence or otherwise) arising in any way out of
// the use of this software, even if advised of the possibility of such damage.
//
//M*/
#include "precomp.hpp"
#include "grfmt_jpeg.hpp"
#ifdef HAVE_JPEG
#include <opencv2/core/utils/logger.hpp>
#ifdef _MSC_VER
//interaction between '_setjmp' and C++ object destruction is non-portable
#pragma warning(disable: 4611)
#endif
#include <stdio.h>
#include <setjmp.h>
// the following defines are a hack to avoid multiple problems with frame pointer handling and setjmp
// see http://gcc.gnu.org/ml/gcc/2011-10/msg00324.html for some details
#define mingw_getsp(...) 0
#define __builtin_frame_address(...) 0
#ifdef _WIN32
#define XMD_H // prevent redefinition of INT32
#undef FAR // prevent FAR redefinition
#endif
#if defined _WIN32 && defined __GNUC__
typedef unsigned char boolean;
#endif
#undef FALSE
#undef TRUE
extern "C" {
#include "jpeglib.h"
}
#ifndef CV_MANUAL_JPEG_STD_HUFF_TABLES
#if defined(LIBJPEG_TURBO_VERSION_NUMBER) && LIBJPEG_TURBO_VERSION_NUMBER >= 1003090
#define CV_MANUAL_JPEG_STD_HUFF_TABLES 0 // libjpeg-turbo handles standard huffman tables itself (jstdhuff.c)
#else
#define CV_MANUAL_JPEG_STD_HUFF_TABLES 1
#endif
#endif
#if CV_MANUAL_JPEG_STD_HUFF_TABLES == 0
#undef CV_MANUAL_JPEG_STD_HUFF_TABLES
#endif
namespace cv
{
struct JpegErrorMgr
{
struct jpeg_error_mgr pub;
jmp_buf setjmp_buffer;
};
struct JpegSource
{
struct jpeg_source_mgr pub;
int skip;
};
struct JpegState
{
jpeg_decompress_struct cinfo; // IJG JPEG codec structure
JpegErrorMgr jerr; // error processing manager state
JpegSource source; // memory buffer source
};
/////////////////////// Error processing /////////////////////
METHODDEF(void)
stub(j_decompress_ptr)
{
}
METHODDEF(boolean)
fill_input_buffer(j_decompress_ptr)
{
return FALSE;
}
// emulating memory input stream
METHODDEF(void)
skip_input_data(j_decompress_ptr cinfo, long num_bytes)
{
JpegSource* source = (JpegSource*) cinfo->src;
if( num_bytes > (long)source->pub.bytes_in_buffer )
{
// We need to skip more data than we have in the buffer.
// This will force the JPEG library to suspend decoding.
source->skip = (int)(num_bytes - source->pub.bytes_in_buffer);
source->pub.next_input_byte += source->pub.bytes_in_buffer;
source->pub.bytes_in_buffer = 0;
}
else
{
// Skip portion of the buffer
source->pub.bytes_in_buffer -= num_bytes;
source->pub.next_input_byte += num_bytes;
source->skip = 0;
}
}
static void jpeg_buffer_src(j_decompress_ptr cinfo, JpegSource* source)
{
cinfo->src = &source->pub;
// Prepare for suspending reader
source->pub.init_source = stub;
source->pub.fill_input_buffer = fill_input_buffer;
source->pub.skip_input_data = skip_input_data;
source->pub.resync_to_restart = jpeg_resync_to_restart;
source->pub.term_source = stub;
source->pub.bytes_in_buffer = 0; // forces fill_input_buffer on first read
source->skip = 0;
}
METHODDEF(void)
error_exit( j_common_ptr cinfo )
{
JpegErrorMgr* err_mgr = (JpegErrorMgr*)(cinfo->err);
/* Return control to the setjmp point */
longjmp( err_mgr->setjmp_buffer, 1 );
}
/////////////////////// JpegDecoder ///////////////////
JpegDecoder::JpegDecoder()
{
m_signature = "\xFF\xD8\xFF";
m_state = 0;
m_f = 0;
m_buf_supported = true;
}
JpegDecoder::~JpegDecoder()
{
close();
}
void JpegDecoder::close()
{
if( m_state )
{
JpegState* state = (JpegState*)m_state;
jpeg_destroy_decompress( &state->cinfo );
delete state;
m_state = 0;
}
if( m_f )
{
fclose( m_f );
m_f = 0;
}
m_width = m_height = 0;
m_type = -1;
}
ImageDecoder JpegDecoder::newDecoder() const
{
return makePtr<JpegDecoder>();
}
bool JpegDecoder::readHeader()
{
volatile bool result = false;
close();
JpegState* state = new JpegState;
m_state = state;
state->cinfo.err = jpeg_std_error(&state->jerr.pub);
state->jerr.pub.error_exit = error_exit;
if( setjmp( state->jerr.setjmp_buffer ) == 0 )
{
jpeg_create_decompress( &state->cinfo );
if( !m_buf.empty() )
{
jpeg_buffer_src(&state->cinfo, &state->source);
state->source.pub.next_input_byte = m_buf.ptr();
state->source.pub.bytes_in_buffer = m_buf.cols*m_buf.rows*m_buf.elemSize();
}
else
{
m_f = fopen( m_filename.c_str(), "rb" );
if( m_f )
jpeg_stdio_src( &state->cinfo, m_f );
}
if (state->cinfo.src != 0)
{
jpeg_save_markers(&state->cinfo, APP1, 0xffff);
jpeg_read_header( &state->cinfo, TRUE );
state->cinfo.scale_num=1;
state->cinfo.scale_denom = m_scale_denom;
m_scale_denom=1; // trick! to know which decoder used scale_denom see imread_
jpeg_calc_output_dimensions(&state->cinfo);
m_width = state->cinfo.output_width;
m_height = state->cinfo.output_height;
m_type = state->cinfo.num_components > 1 ? CV_8UC3 : CV_8UC1;
result = true;
}
}
return result;
}
#ifdef CV_MANUAL_JPEG_STD_HUFF_TABLES
/***************************************************************************
* following code is for supporting MJPEG image files
* based on a message of Laurent Pinchart on the video4linux mailing list
***************************************************************************/
/* JPEG DHT Segment for YCrCb omitted from MJPEG data */
static
unsigned char my_jpeg_odml_dht[0x1a4] = {
0xff, 0xc4, 0x01, 0xa2,
0x00, 0x00, 0x01, 0x05, 0x01, 0x01, 0x01, 0x01, 0x01, 0x01, 0x00, 0x00,
0x00, 0x00, 0x00, 0x00, 0x00,
0x00, 0x01, 0x02, 0x03, 0x04, 0x05, 0x06, 0x07, 0x08, 0x09, 0x0a, 0x0b,
0x01, 0x00, 0x03, 0x01, 0x01, 0x01, 0x01, 0x01, 0x01, 0x01, 0x01, 0x01,
0x00, 0x00, 0x00, 0x00, 0x00,
0x00, 0x01, 0x02, 0x03, 0x04, 0x05, 0x06, 0x07, 0x08, 0x09, 0x0a, 0x0b,
0x10, 0x00, 0x02, 0x01, 0x03, 0x03, 0x02, 0x04, 0x03, 0x05, 0x05, 0x04,
0x04, 0x00, 0x00, 0x01, 0x7d,
0x01, 0x02, 0x03, 0x00, 0x04, 0x11, 0x05, 0x12, 0x21, 0x31, 0x41, 0x06,
0x13, 0x51, 0x61, 0x07,
0x22, 0x71, 0x14, 0x32, 0x81, 0x91, 0xa1, 0x08, 0x23, 0x42, 0xb1, 0xc1,
0x15, 0x52, 0xd1, 0xf0,
0x24, 0x33, 0x62, 0x72, 0x82, 0x09, 0x0a, 0x16, 0x17, 0x18, 0x19, 0x1a,
0x25, 0x26, 0x27, 0x28,
0x29, 0x2a, 0x34, 0x35, 0x36, 0x37, 0x38, 0x39, 0x3a, 0x43, 0x44, 0x45,
0x46, 0x47, 0x48, 0x49,
0x4a, 0x53, 0x54, 0x55, 0x56, 0x57, 0x58, 0x59, 0x5a, 0x63, 0x64, 0x65,
0x66, 0x67, 0x68, 0x69,
0x6a, 0x73, 0x74, 0x75, 0x76, 0x77, 0x78, 0x79, 0x7a, 0x83, 0x84, 0x85,
0x86, 0x87, 0x88, 0x89,
0x8a, 0x92, 0x93, 0x94, 0x95, 0x96, 0x97, 0x98, 0x99, 0x9a, 0xa2, 0xa3,
0xa4, 0xa5, 0xa6, 0xa7,
0xa8, 0xa9, 0xaa, 0xb2, 0xb3, 0xb4, 0xb5, 0xb6, 0xb7, 0xb8, 0xb9, 0xba,
0xc2, 0xc3, 0xc4, 0xc5,
0xc6, 0xc7, 0xc8, 0xc9, 0xca, 0xd2, 0xd3, 0xd4, 0xd5, 0xd6, 0xd7, 0xd8,
0xd9, 0xda, 0xe1, 0xe2,
0xe3, 0xe4, 0xe5, 0xe6, 0xe7, 0xe8, 0xe9, 0xea, 0xf1, 0xf2, 0xf3, 0xf4,
0xf5, 0xf6, 0xf7, 0xf8,
0xf9, 0xfa,
0x11, 0x00, 0x02, 0x01, 0x02, 0x04, 0x04, 0x03, 0x04, 0x07, 0x05, 0x04,
0x04, 0x00, 0x01, 0x02, 0x77,
0x00, 0x01, 0x02, 0x03, 0x11, 0x04, 0x05, 0x21, 0x31, 0x06, 0x12, 0x41,
0x51, 0x07, 0x61, 0x71,
0x13, 0x22, 0x32, 0x81, 0x08, 0x14, 0x42, 0x91, 0xa1, 0xb1, 0xc1, 0x09,
0x23, 0x33, 0x52, 0xf0,
0x15, 0x62, 0x72, 0xd1, 0x0a, 0x16, 0x24, 0x34, 0xe1, 0x25, 0xf1, 0x17,
0x18, 0x19, 0x1a, 0x26,
0x27, 0x28, 0x29, 0x2a, 0x35, 0x36, 0x37, 0x38, 0x39, 0x3a, 0x43, 0x44,
0x45, 0x46, 0x47, 0x48,
0x49, 0x4a, 0x53, 0x54, 0x55, 0x56, 0x57, 0x58, 0x59, 0x5a, 0x63, 0x64,
0x65, 0x66, 0x67, 0x68,
0x69, 0x6a, 0x73, 0x74, 0x75, 0x76, 0x77, 0x78, 0x79, 0x7a, 0x82, 0x83,
0x84, 0x85, 0x86, 0x87,
0x88, 0x89, 0x8a, 0x92, 0x93, 0x94, 0x95, 0x96, 0x97, 0x98, 0x99, 0x9a,
0xa2, 0xa3, 0xa4, 0xa5,
0xa6, 0xa7, 0xa8, 0xa9, 0xaa, 0xb2, 0xb3, 0xb4, 0xb5, 0xb6, 0xb7, 0xb8,
0xb9, 0xba, 0xc2, 0xc3,
0xc4, 0xc5, 0xc6, 0xc7, 0xc8, 0xc9, 0xca, 0xd2, 0xd3, 0xd4, 0xd5, 0xd6,
0xd7, 0xd8, 0xd9, 0xda,
0xe2, 0xe3, 0xe4, 0xe5, 0xe6, 0xe7, 0xe8, 0xe9, 0xea, 0xf2, 0xf3, 0xf4,
0xf5, 0xf6, 0xf7, 0xf8,
0xf9, 0xfa
};
/*
* Parse the DHT table.
* This code comes from jpeg6b (jdmarker.c).
*/
static
int my_jpeg_load_dht (struct jpeg_decompress_struct *info, unsigned char *dht,
JHUFF_TBL *ac_tables[], JHUFF_TBL *dc_tables[])
{
unsigned int length = (dht[2] << 8) + dht[3] - 2;
unsigned int pos = 4;
unsigned int count, i;
int index;
JHUFF_TBL **hufftbl;
unsigned char bits[17];
unsigned char huffval[256] = {0};
while (length > 16)
{
bits[0] = 0;
index = dht[pos++];
count = 0;
for (i = 1; i <= 16; ++i)
{
bits[i] = dht[pos++];
count += bits[i];
}
length -= 17;
if (count > 256 || count > length)
return -1;
for (i = 0; i < count; ++i)
huffval[i] = dht[pos++];
length -= count;
if (index & 0x10)
{
index &= ~0x10;
hufftbl = &ac_tables[index];
}
else
hufftbl = &dc_tables[index];
if (index < 0 || index >= NUM_HUFF_TBLS)
return -1;
if (*hufftbl == NULL)
*hufftbl = jpeg_alloc_huff_table ((j_common_ptr)info);
if (*hufftbl == NULL)
return -1;
memcpy ((*hufftbl)->bits, bits, sizeof (*hufftbl)->bits);
memcpy ((*hufftbl)->huffval, huffval, sizeof (*hufftbl)->huffval);
}
if (length != 0)
return -1;
return 0;
}
/***************************************************************************
* end of code for supportting MJPEG image files
* based on a message of Laurent Pinchart on the video4linux mailing list
***************************************************************************/
#endif // CV_MANUAL_JPEG_STD_HUFF_TABLES
bool JpegDecoder::readData( Mat& img )
{
volatile bool result = false;
size_t step = img.step;
bool color = img.channels() > 1;
if( m_state && m_width && m_height )
{
jpeg_decompress_struct* cinfo = &((JpegState*)m_state)->cinfo;
JpegErrorMgr* jerr = &((JpegState*)m_state)->jerr;
JSAMPARRAY buffer = 0;
if( setjmp( jerr->setjmp_buffer ) == 0 )
{
#ifdef CV_MANUAL_JPEG_STD_HUFF_TABLES
/* check if this is a mjpeg image format */
if ( cinfo->ac_huff_tbl_ptrs[0] == NULL &&
cinfo->ac_huff_tbl_ptrs[1] == NULL &&
cinfo->dc_huff_tbl_ptrs[0] == NULL &&
cinfo->dc_huff_tbl_ptrs[1] == NULL )
{
/* yes, this is a mjpeg image format, so load the correct
huffman table */
my_jpeg_load_dht( cinfo,
my_jpeg_odml_dht,
cinfo->ac_huff_tbl_ptrs,
cinfo->dc_huff_tbl_ptrs );
}
#endif
if( color )
{
if( cinfo->num_components != 4 )
{
cinfo->out_color_space = JCS_RGB;
cinfo->out_color_components = 3;
}
else
{
cinfo->out_color_space = JCS_CMYK;
cinfo->out_color_components = 4;
}
}
else
{
if( cinfo->num_components != 4 )
{
cinfo->out_color_space = JCS_GRAYSCALE;
cinfo->out_color_components = 1;
}
else
{
cinfo->out_color_space = JCS_CMYK;
cinfo->out_color_components = 4;
}
}
// Check for Exif marker APP1
jpeg_saved_marker_ptr exif_marker = NULL;
jpeg_saved_marker_ptr cmarker = cinfo->marker_list;
while( cmarker && exif_marker == NULL )
{
if (cmarker->marker == APP1)
exif_marker = cmarker;
cmarker = cmarker->next;
}
// Parse Exif data
if( exif_marker )
{
const std::streamsize offsetToTiffHeader = 6; //bytes from Exif size field to the first TIFF header
if (exif_marker->data_length > offsetToTiffHeader)
{
m_exif.parseExif(exif_marker->data + offsetToTiffHeader, exif_marker->data_length - offsetToTiffHeader);
}
}
jpeg_start_decompress( cinfo );
buffer = (*cinfo->mem->alloc_sarray)((j_common_ptr)cinfo,
JPOOL_IMAGE, m_width*4, 1 );
uchar* data = img.ptr();
for( ; m_height--; data += step )
{
jpeg_read_scanlines( cinfo, buffer, 1 );
if( color )
{
if( cinfo->out_color_components == 3 )
icvCvt_RGB2BGR_8u_C3R( buffer[0], 0, data, 0, Size(m_width,1) );
else
icvCvt_CMYK2BGR_8u_C4C3R( buffer[0], 0, data, 0, Size(m_width,1) );
}
else
{
if( cinfo->out_color_components == 1 )
memcpy( data, buffer[0], m_width );
else
icvCvt_CMYK2Gray_8u_C4C1R( buffer[0], 0, data, 0, Size(m_width,1) );
}
}
result = true;
jpeg_finish_decompress( cinfo );
}
}
return result;
}
/////////////////////// JpegEncoder ///////////////////
struct JpegDestination
{
struct jpeg_destination_mgr pub;
std::vector<uchar> *buf, *dst;
};
METHODDEF(void)
stub(j_compress_ptr)
{
}
METHODDEF(void)
term_destination (j_compress_ptr cinfo)
{
JpegDestination* dest = (JpegDestination*)cinfo->dest;
size_t sz = dest->dst->size(), bufsz = dest->buf->size() - dest->pub.free_in_buffer;
if( bufsz > 0 )
{
dest->dst->resize(sz + bufsz);
memcpy( &(*dest->dst)[0] + sz, &(*dest->buf)[0], bufsz);
}
}
METHODDEF(boolean)
empty_output_buffer (j_compress_ptr cinfo)
{
JpegDestination* dest = (JpegDestination*)cinfo->dest;
size_t sz = dest->dst->size(), bufsz = dest->buf->size();
dest->dst->resize(sz + bufsz);
memcpy( &(*dest->dst)[0] + sz, &(*dest->buf)[0], bufsz);
dest->pub.next_output_byte = &(*dest->buf)[0];
dest->pub.free_in_buffer = bufsz;
return TRUE;
}
static void jpeg_buffer_dest(j_compress_ptr cinfo, JpegDestination* destination)
{
cinfo->dest = &destination->pub;
destination->pub.init_destination = stub;
destination->pub.empty_output_buffer = empty_output_buffer;
destination->pub.term_destination = term_destination;
}
JpegEncoder::JpegEncoder()
{
m_description = "JPEG files (*.jpeg;*.jpg;*.jpe)";
m_buf_supported = true;
}
JpegEncoder::~JpegEncoder()
{
}
ImageEncoder JpegEncoder::newEncoder() const
{
return makePtr<JpegEncoder>();
}
bool JpegEncoder::write( const Mat& img, const std::vector<int>& params )
{
m_last_error.clear();
struct fileWrapper
{
FILE* f;
fileWrapper() : f(0) {}
~fileWrapper() { if(f) fclose(f); }
};
volatile bool result = false;
fileWrapper fw;
int width = img.cols, height = img.rows;
std::vector<uchar> out_buf(1 << 12);
AutoBuffer<uchar> _buffer;
uchar* buffer;
struct jpeg_compress_struct cinfo;
JpegErrorMgr jerr;
JpegDestination dest;
cinfo.err = jpeg_std_error(&jerr.pub);
jerr.pub.error_exit = error_exit;
jpeg_create_compress(&cinfo);
if( !m_buf )
{
fw.f = fopen( m_filename.c_str(), "wb" );
if( !fw.f )
goto _exit_;
jpeg_stdio_dest( &cinfo, fw.f );
}
else
{
dest.dst = m_buf;
dest.buf = &out_buf;
jpeg_buffer_dest( &cinfo, &dest );
dest.pub.next_output_byte = &out_buf[0];
dest.pub.free_in_buffer = out_buf.size();
}
if( setjmp( jerr.setjmp_buffer ) == 0 )
{
cinfo.image_width = width;
cinfo.image_height = height;
int _channels = img.channels();
int channels = _channels > 1 ? 3 : 1;
cinfo.input_components = channels;
cinfo.in_color_space = channels > 1 ? JCS_RGB : JCS_GRAYSCALE;
int quality = 95;
int progressive = 0;
int optimize = 0;
int rst_interval = 0;
int luma_quality = -1;
int chroma_quality = -1;
uint32_t sampling_factor = 0; // same as 0x221111
for( size_t i = 0; i < params.size(); i += 2 )
{
if( params[i] == IMWRITE_JPEG_QUALITY )
{
quality = params[i+1];
quality = MIN(MAX(quality, 0), 100);
}
if( params[i] == IMWRITE_JPEG_PROGRESSIVE )
{
progressive = params[i+1];
}
if( params[i] == IMWRITE_JPEG_OPTIMIZE )
{
optimize = params[i+1];
}
if( params[i] == IMWRITE_JPEG_LUMA_QUALITY )
{
if (params[i+1] >= 0)
{
luma_quality = MIN(MAX(params[i+1], 0), 100);
quality = luma_quality;
if (chroma_quality < 0)
{
chroma_quality = luma_quality;
}
}
}
if( params[i] == IMWRITE_JPEG_CHROMA_QUALITY )
{
if (params[i+1] >= 0)
{
chroma_quality = MIN(MAX(params[i+1], 0), 100);
}
}
if( params[i] == IMWRITE_JPEG_RST_INTERVAL )
{
rst_interval = params[i+1];
rst_interval = MIN(MAX(rst_interval, 0), 65535L);
}
if( params[i] == IMWRITE_JPEG_SAMPLING_FACTOR )
{
sampling_factor = static_cast<uint32_t>(params[i+1]);
switch ( sampling_factor )
{
case IMWRITE_JPEG_SAMPLING_FACTOR_411:
case IMWRITE_JPEG_SAMPLING_FACTOR_420:
case IMWRITE_JPEG_SAMPLING_FACTOR_422:
case IMWRITE_JPEG_SAMPLING_FACTOR_440:
case IMWRITE_JPEG_SAMPLING_FACTOR_444:
// OK.
break;
default:
CV_LOG_WARNING(NULL, cv::format("Unknown value for IMWRITE_JPEG_SAMPLING_FACTOR: 0x%06x", sampling_factor ) );
sampling_factor = 0;
break;
}
}
}
jpeg_set_defaults( &cinfo );
cinfo.restart_interval = rst_interval;
jpeg_set_quality( &cinfo, quality,
TRUE /* limit to baseline-JPEG values */ );
if( progressive )
jpeg_simple_progression( &cinfo );
if( optimize )
cinfo.optimize_coding = TRUE;
if( (channels > 1) && ( sampling_factor != 0 ) )
{
cinfo.comp_info[0].v_samp_factor = (sampling_factor >> 16 ) & 0xF;
cinfo.comp_info[0].h_samp_factor = (sampling_factor >> 20 ) & 0xF;
cinfo.comp_info[1].v_samp_factor = 1;
cinfo.comp_info[1].h_samp_factor = 1;
}
#if JPEG_LIB_VERSION >= 70
if (luma_quality >= 0 && chroma_quality >= 0)
{
cinfo.q_scale_factor[0] = jpeg_quality_scaling(luma_quality);
cinfo.q_scale_factor[1] = jpeg_quality_scaling(chroma_quality);
if ( luma_quality != chroma_quality )
{
/* disable subsampling - ref. Libjpeg.txt */
cinfo.comp_info[0].v_samp_factor = 1;
cinfo.comp_info[0].h_samp_factor = 1;
cinfo.comp_info[1].v_samp_factor = 1;
cinfo.comp_info[1].h_samp_factor = 1;
}
jpeg_default_qtables( &cinfo, TRUE );
}
#endif // #if JPEG_LIB_VERSION >= 70
jpeg_start_compress( &cinfo, TRUE );
if( channels > 1 )
_buffer.allocate(width*channels);
buffer = _buffer.data();
for( int y = 0; y < height; y++ )
{
uchar *data = img.data + img.step*y, *ptr = data;
if( _channels == 3 )
{
icvCvt_BGR2RGB_8u_C3R( data, 0, buffer, 0, Size(width,1) );
ptr = buffer;
}
else if( _channels == 4 )
{
icvCvt_BGRA2BGR_8u_C4C3R( data, 0, buffer, 0, Size(width,1), 2 );
ptr = buffer;
}
jpeg_write_scanlines( &cinfo, &ptr, 1 );
}
jpeg_finish_compress( &cinfo );
result = true;
}
_exit_:
if(!result)
{
char jmsg_buf[JMSG_LENGTH_MAX];
jerr.pub.format_message((j_common_ptr)&cinfo, jmsg_buf);
m_last_error = jmsg_buf;
}
jpeg_destroy_compress( &cinfo );
return result;
}
}
#endif
/* End of file. */
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