diff options
Diffstat (limited to 'Source/WebCore/platform/image-encoders/JPEGImageEncoder.cpp')
-rw-r--r-- | Source/WebCore/platform/image-encoders/JPEGImageEncoder.cpp | 135 |
1 files changed, 135 insertions, 0 deletions
diff --git a/Source/WebCore/platform/image-encoders/JPEGImageEncoder.cpp b/Source/WebCore/platform/image-encoders/JPEGImageEncoder.cpp new file mode 100644 index 0000000..d707aa8 --- /dev/null +++ b/Source/WebCore/platform/image-encoders/JPEGImageEncoder.cpp @@ -0,0 +1,135 @@ +/* + * 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->free_in_buffer); + 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) +{ + struct jpeg_compress_struct compressData = { 0 }; + 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); + jpeg_set_quality(&compressData, 65, 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)) + 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); + return true; +} + +} // namespace WebCore |