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/*
* Copyright (C) 2009 Torch Mobile, Inc. All rights reserved.
* Copyright (C) Research In Motion Limited 2009-2010. All rights reserved.
*
* This library is free software; you can redistribute it and/or
* modify it under the terms of the GNU Library General Public
* License as published by the Free Software Foundation; either
* version 2 of the License, or (at your option) any later version.
*
* This library is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* Library General Public License for more details.
*
* You should have received a copy of the GNU Library General Public License
* along with this library; see the file COPYING.LIB. If not, write to
* the Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor,
* Boston, MA 02110-1301, USA.
*/
#include "config.h"
#include "JPEGImageEncoder.h"
#include "IntSize.h"
// FIXME: jpeglib.h requires stdio.h to be included first for FILE
#include <stdio.h>
#include "jpeglib.h"
#include <setjmp.h>
namespace WebCore {
class JPEGDestinationManager : public jpeg_destination_mgr {
public:
explicit JPEGDestinationManager(Vector<char>& toDump)
: m_dump(toDump)
{
// Zero base class memory.
jpeg_destination_mgr* base = this;
memset(base, 0, sizeof(jpeg_destination_mgr));
}
Vector<char> m_buffer;
Vector<char>& m_dump;
};
class JPEGCompressErrorMgr : public jpeg_error_mgr {
public:
JPEGCompressErrorMgr()
{
// Zero memory
memset(this, 0, sizeof(JPEGCompressErrorMgr));
}
jmp_buf m_setjmpBuffer;
};
static void jpegInitializeDestination(j_compress_ptr compressData)
{
JPEGDestinationManager* dest = static_cast<JPEGDestinationManager*>(compressData->dest);
dest->m_buffer.resize(4096);
dest->next_output_byte = reinterpret_cast<JOCTET*>(dest->m_buffer.data());
dest->free_in_buffer = dest->m_buffer.size();
}
static boolean jpegEmptyOutputBuffer(j_compress_ptr compressData)
{
JPEGDestinationManager* dest = static_cast<JPEGDestinationManager*>(compressData->dest);
dest->m_dump.append(dest->m_buffer.data(), dest->m_buffer.size());
dest->next_output_byte = reinterpret_cast<JOCTET*>(dest->m_buffer.data());
dest->free_in_buffer = dest->m_buffer.size();
return TRUE;
}
static void jpegTerminateDestination(j_compress_ptr compressData)
{
JPEGDestinationManager* dest = static_cast<JPEGDestinationManager*>(compressData->dest);
dest->m_dump.append(dest->m_buffer.data(), dest->m_buffer.size() - dest->free_in_buffer);
}
static void jpegErrorExit(j_common_ptr compressData)
{
JPEGCompressErrorMgr* err = static_cast<JPEGCompressErrorMgr*>(compressData->err);
longjmp(err->m_setjmpBuffer, -1);
}
bool compressRGBABigEndianToJPEG(unsigned char* rgbaBigEndianData, const IntSize& size, Vector<char>& jpegData, const double* quality)
{
struct jpeg_compress_struct compressData;
JPEGCompressErrorMgr err;
compressData.err = jpeg_std_error(&err);
err.error_exit = jpegErrorExit;
jpeg_create_compress(&compressData);
JPEGDestinationManager dest(jpegData);
compressData.dest = &dest;
dest.init_destination = jpegInitializeDestination;
dest.empty_output_buffer = jpegEmptyOutputBuffer;
dest.term_destination = jpegTerminateDestination;
compressData.image_width = size.width();
compressData.image_height = size.height();
compressData.input_components = 3;
compressData.in_color_space = JCS_RGB;
jpeg_set_defaults(&compressData);
int compressionQuality = 65;
if (quality && *quality >= 0.0 && *quality <= 1.0)
compressionQuality = static_cast<int>(*quality * 100 + 0.5);
jpeg_set_quality(&compressData, compressionQuality, FALSE);
// rowBuffer must be defined here so that its destructor is always called even when "setjmp" catches an error.
Vector<JSAMPLE, 600 * 3> rowBuffer;
if (setjmp(err.m_setjmpBuffer)) {
jpeg_destroy_compress(&compressData);
return false;
}
jpeg_start_compress(&compressData, TRUE);
rowBuffer.resize(compressData.image_width * 3);
const unsigned char* pixel = rgbaBigEndianData;
const unsigned char* pixelEnd = pixel + compressData.image_width * compressData.image_height * 4;
while (pixel < pixelEnd) {
JSAMPLE* output = rowBuffer.data();
for (const unsigned char* rowEnd = pixel + compressData.image_width * 4; pixel < rowEnd;) {
*output++ = static_cast<JSAMPLE>(*pixel++ & 0xFF); // red
*output++ = static_cast<JSAMPLE>(*pixel++ & 0xFF); // green
*output++ = static_cast<JSAMPLE>(*pixel++ & 0xFF); // blue
++pixel; // skip alpha
}
output = rowBuffer.data();
jpeg_write_scanlines(&compressData, &output, 1);
}
jpeg_finish_compress(&compressData);
jpeg_destroy_compress(&compressData);
return true;
}
} // namespace WebCore
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