574 lines
18 KiB
C++
574 lines
18 KiB
C++
/*
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* Copyright 2012 The LibYuv Project Authors. All rights reserved.
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*
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* Use of this source code is governed by a BSD-style license
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* that can be found in the LICENSE file in the root of the source
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* tree. An additional intellectual property rights grant can be found
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* in the file PATENTS. All contributing project authors may
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* be found in the AUTHORS file in the root of the source tree.
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*/
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#include "libyuv/mjpeg_decoder.h"
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#ifdef HAVE_JPEG
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#include <assert.h>
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#if !defined(__pnacl__) && !defined(__CLR_VER) && \
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!defined(COVERAGE_ENABLED) && !defined(TARGET_IPHONE_SIMULATOR)
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// Must be included before jpeglib.
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#include <setjmp.h>
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#define HAVE_SETJMP
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#if defined(_MSC_VER)
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// disable warning 4324: structure was padded due to __declspec(align())
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#pragma warning(disable : 4324)
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#endif
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#endif
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struct FILE; // For jpeglib.h.
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// C++ build requires extern C for jpeg internals.
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#ifdef __cplusplus
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extern "C" {
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#endif
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#include <jpeglib.h>
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#ifdef __cplusplus
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} // extern "C"
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#endif
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#include "libyuv/planar_functions.h" // For CopyPlane().
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namespace libyuv {
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#ifdef HAVE_SETJMP
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struct SetJmpErrorMgr {
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jpeg_error_mgr base; // Must be at the top
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jmp_buf setjmp_buffer;
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};
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#endif
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const int MJpegDecoder::kColorSpaceUnknown = JCS_UNKNOWN;
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const int MJpegDecoder::kColorSpaceGrayscale = JCS_GRAYSCALE;
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const int MJpegDecoder::kColorSpaceRgb = JCS_RGB;
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const int MJpegDecoder::kColorSpaceYCbCr = JCS_YCbCr;
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const int MJpegDecoder::kColorSpaceCMYK = JCS_CMYK;
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const int MJpegDecoder::kColorSpaceYCCK = JCS_YCCK;
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// Methods that are passed to jpeglib.
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boolean fill_input_buffer(jpeg_decompress_struct* cinfo);
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void init_source(jpeg_decompress_struct* cinfo);
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void skip_input_data(jpeg_decompress_struct* cinfo, long num_bytes); // NOLINT
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void term_source(jpeg_decompress_struct* cinfo);
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void ErrorHandler(jpeg_common_struct* cinfo);
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void OutputHandler(jpeg_common_struct* cinfo);
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MJpegDecoder::MJpegDecoder()
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: has_scanline_padding_(LIBYUV_FALSE),
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num_outbufs_(0),
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scanlines_(NULL),
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scanlines_sizes_(NULL),
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databuf_(NULL),
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databuf_strides_(NULL) {
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decompress_struct_ = new jpeg_decompress_struct;
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source_mgr_ = new jpeg_source_mgr;
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#ifdef HAVE_SETJMP
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error_mgr_ = new SetJmpErrorMgr;
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decompress_struct_->err = jpeg_std_error(&error_mgr_->base);
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// Override standard exit()-based error handler.
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error_mgr_->base.error_exit = &ErrorHandler;
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error_mgr_->base.output_message = &OutputHandler;
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#endif
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decompress_struct_->client_data = NULL;
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source_mgr_->init_source = &init_source;
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source_mgr_->fill_input_buffer = &fill_input_buffer;
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source_mgr_->skip_input_data = &skip_input_data;
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source_mgr_->resync_to_restart = &jpeg_resync_to_restart;
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source_mgr_->term_source = &term_source;
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jpeg_create_decompress(decompress_struct_);
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decompress_struct_->src = source_mgr_;
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buf_vec_.buffers = &buf_;
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buf_vec_.len = 1;
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}
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MJpegDecoder::~MJpegDecoder() {
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jpeg_destroy_decompress(decompress_struct_);
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delete decompress_struct_;
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delete source_mgr_;
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#ifdef HAVE_SETJMP
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delete error_mgr_;
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#endif
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DestroyOutputBuffers();
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}
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LIBYUV_BOOL MJpegDecoder::LoadFrame(const uint8* src, size_t src_len) {
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if (!ValidateJpeg(src, src_len)) {
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return LIBYUV_FALSE;
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}
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buf_.data = src;
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buf_.len = static_cast<int>(src_len);
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buf_vec_.pos = 0;
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decompress_struct_->client_data = &buf_vec_;
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#ifdef HAVE_SETJMP
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if (setjmp(error_mgr_->setjmp_buffer)) {
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// We called jpeg_read_header, it experienced an error, and we called
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// longjmp() and rewound the stack to here. Return error.
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return LIBYUV_FALSE;
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}
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#endif
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if (jpeg_read_header(decompress_struct_, TRUE) != JPEG_HEADER_OK) {
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// ERROR: Bad MJPEG header
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return LIBYUV_FALSE;
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}
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AllocOutputBuffers(GetNumComponents());
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for (int i = 0; i < num_outbufs_; ++i) {
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int scanlines_size = GetComponentScanlinesPerImcuRow(i);
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if (scanlines_sizes_[i] != scanlines_size) {
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if (scanlines_[i]) {
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delete scanlines_[i];
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}
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scanlines_[i] = new uint8*[scanlines_size];
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scanlines_sizes_[i] = scanlines_size;
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}
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// We allocate padding for the final scanline to pad it up to DCTSIZE bytes
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// to avoid memory errors, since jpeglib only reads full MCUs blocks. For
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// the preceding scanlines, the padding is not needed/wanted because the
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// following addresses will already be valid (they are the initial bytes of
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// the next scanline) and will be overwritten when jpeglib writes out that
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// next scanline.
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int databuf_stride = GetComponentStride(i);
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int databuf_size = scanlines_size * databuf_stride;
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if (databuf_strides_[i] != databuf_stride) {
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if (databuf_[i]) {
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delete databuf_[i];
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}
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databuf_[i] = new uint8[databuf_size];
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databuf_strides_[i] = databuf_stride;
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}
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if (GetComponentStride(i) != GetComponentWidth(i)) {
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has_scanline_padding_ = LIBYUV_TRUE;
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}
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}
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return LIBYUV_TRUE;
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}
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static int DivideAndRoundUp(int numerator, int denominator) {
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return (numerator + denominator - 1) / denominator;
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}
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static int DivideAndRoundDown(int numerator, int denominator) {
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return numerator / denominator;
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}
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// Returns width of the last loaded frame.
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int MJpegDecoder::GetWidth() {
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return decompress_struct_->image_width;
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}
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// Returns height of the last loaded frame.
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int MJpegDecoder::GetHeight() {
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return decompress_struct_->image_height;
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}
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// Returns format of the last loaded frame. The return value is one of the
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// kColorSpace* constants.
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int MJpegDecoder::GetColorSpace() {
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return decompress_struct_->jpeg_color_space;
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}
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// Number of color components in the color space.
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int MJpegDecoder::GetNumComponents() {
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return decompress_struct_->num_components;
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}
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// Sample factors of the n-th component.
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int MJpegDecoder::GetHorizSampFactor(int component) {
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return decompress_struct_->comp_info[component].h_samp_factor;
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}
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int MJpegDecoder::GetVertSampFactor(int component) {
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return decompress_struct_->comp_info[component].v_samp_factor;
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}
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int MJpegDecoder::GetHorizSubSampFactor(int component) {
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return decompress_struct_->max_h_samp_factor / GetHorizSampFactor(component);
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}
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int MJpegDecoder::GetVertSubSampFactor(int component) {
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return decompress_struct_->max_v_samp_factor / GetVertSampFactor(component);
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}
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int MJpegDecoder::GetImageScanlinesPerImcuRow() {
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return decompress_struct_->max_v_samp_factor * DCTSIZE;
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}
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int MJpegDecoder::GetComponentScanlinesPerImcuRow(int component) {
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int vs = GetVertSubSampFactor(component);
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return DivideAndRoundUp(GetImageScanlinesPerImcuRow(), vs);
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}
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int MJpegDecoder::GetComponentWidth(int component) {
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int hs = GetHorizSubSampFactor(component);
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return DivideAndRoundUp(GetWidth(), hs);
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}
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int MJpegDecoder::GetComponentHeight(int component) {
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int vs = GetVertSubSampFactor(component);
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return DivideAndRoundUp(GetHeight(), vs);
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}
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// Get width in bytes padded out to a multiple of DCTSIZE
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int MJpegDecoder::GetComponentStride(int component) {
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return (GetComponentWidth(component) + DCTSIZE - 1) & ~(DCTSIZE - 1);
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}
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int MJpegDecoder::GetComponentSize(int component) {
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return GetComponentWidth(component) * GetComponentHeight(component);
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}
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LIBYUV_BOOL MJpegDecoder::UnloadFrame() {
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#ifdef HAVE_SETJMP
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if (setjmp(error_mgr_->setjmp_buffer)) {
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// We called jpeg_abort_decompress, it experienced an error, and we called
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// longjmp() and rewound the stack to here. Return error.
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return LIBYUV_FALSE;
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}
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#endif
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jpeg_abort_decompress(decompress_struct_);
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return LIBYUV_TRUE;
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}
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// TODO(fbarchard): Allow rectangle to be specified: x, y, width, height.
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LIBYUV_BOOL MJpegDecoder::DecodeToBuffers(uint8** planes,
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int dst_width,
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int dst_height) {
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if (dst_width != GetWidth() || dst_height > GetHeight()) {
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// ERROR: Bad dimensions
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return LIBYUV_FALSE;
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}
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#ifdef HAVE_SETJMP
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if (setjmp(error_mgr_->setjmp_buffer)) {
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// We called into jpeglib, it experienced an error sometime during this
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// function call, and we called longjmp() and rewound the stack to here.
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// Return error.
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return LIBYUV_FALSE;
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}
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#endif
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if (!StartDecode()) {
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return LIBYUV_FALSE;
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}
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SetScanlinePointers(databuf_);
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int lines_left = dst_height;
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// Compute amount of lines to skip to implement vertical crop.
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// TODO(fbarchard): Ensure skip is a multiple of maximum component
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// subsample. ie 2
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int skip = (GetHeight() - dst_height) / 2;
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if (skip > 0) {
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// There is no API to skip lines in the output data, so we read them
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// into the temp buffer.
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while (skip >= GetImageScanlinesPerImcuRow()) {
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if (!DecodeImcuRow()) {
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FinishDecode();
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return LIBYUV_FALSE;
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}
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skip -= GetImageScanlinesPerImcuRow();
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}
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if (skip > 0) {
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// Have a partial iMCU row left over to skip. Must read it and then
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// copy the parts we want into the destination.
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if (!DecodeImcuRow()) {
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FinishDecode();
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return LIBYUV_FALSE;
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}
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for (int i = 0; i < num_outbufs_; ++i) {
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// TODO(fbarchard): Compute skip to avoid this
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assert(skip % GetVertSubSampFactor(i) == 0);
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int rows_to_skip = DivideAndRoundDown(skip, GetVertSubSampFactor(i));
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int scanlines_to_copy =
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GetComponentScanlinesPerImcuRow(i) - rows_to_skip;
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int data_to_skip = rows_to_skip * GetComponentStride(i);
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CopyPlane(databuf_[i] + data_to_skip, GetComponentStride(i), planes[i],
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GetComponentWidth(i), GetComponentWidth(i),
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scanlines_to_copy);
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planes[i] += scanlines_to_copy * GetComponentWidth(i);
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}
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lines_left -= (GetImageScanlinesPerImcuRow() - skip);
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}
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}
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// Read full MCUs but cropped horizontally
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for (; lines_left > GetImageScanlinesPerImcuRow();
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lines_left -= GetImageScanlinesPerImcuRow()) {
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if (!DecodeImcuRow()) {
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FinishDecode();
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return LIBYUV_FALSE;
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}
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for (int i = 0; i < num_outbufs_; ++i) {
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int scanlines_to_copy = GetComponentScanlinesPerImcuRow(i);
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CopyPlane(databuf_[i], GetComponentStride(i), planes[i],
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GetComponentWidth(i), GetComponentWidth(i), scanlines_to_copy);
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planes[i] += scanlines_to_copy * GetComponentWidth(i);
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}
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}
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if (lines_left > 0) {
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// Have a partial iMCU row left over to decode.
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if (!DecodeImcuRow()) {
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FinishDecode();
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return LIBYUV_FALSE;
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}
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for (int i = 0; i < num_outbufs_; ++i) {
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int scanlines_to_copy =
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DivideAndRoundUp(lines_left, GetVertSubSampFactor(i));
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CopyPlane(databuf_[i], GetComponentStride(i), planes[i],
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GetComponentWidth(i), GetComponentWidth(i), scanlines_to_copy);
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planes[i] += scanlines_to_copy * GetComponentWidth(i);
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}
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}
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return FinishDecode();
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}
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LIBYUV_BOOL MJpegDecoder::DecodeToCallback(CallbackFunction fn,
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void* opaque,
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int dst_width,
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int dst_height) {
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if (dst_width != GetWidth() || dst_height > GetHeight()) {
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// ERROR: Bad dimensions
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return LIBYUV_FALSE;
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}
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#ifdef HAVE_SETJMP
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if (setjmp(error_mgr_->setjmp_buffer)) {
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// We called into jpeglib, it experienced an error sometime during this
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// function call, and we called longjmp() and rewound the stack to here.
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// Return error.
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return LIBYUV_FALSE;
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}
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#endif
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if (!StartDecode()) {
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return LIBYUV_FALSE;
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}
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SetScanlinePointers(databuf_);
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int lines_left = dst_height;
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// TODO(fbarchard): Compute amount of lines to skip to implement vertical crop
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int skip = (GetHeight() - dst_height) / 2;
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if (skip > 0) {
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while (skip >= GetImageScanlinesPerImcuRow()) {
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if (!DecodeImcuRow()) {
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FinishDecode();
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return LIBYUV_FALSE;
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}
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skip -= GetImageScanlinesPerImcuRow();
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}
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if (skip > 0) {
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// Have a partial iMCU row left over to skip.
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if (!DecodeImcuRow()) {
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FinishDecode();
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return LIBYUV_FALSE;
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}
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for (int i = 0; i < num_outbufs_; ++i) {
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// TODO(fbarchard): Compute skip to avoid this
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assert(skip % GetVertSubSampFactor(i) == 0);
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int rows_to_skip = DivideAndRoundDown(skip, GetVertSubSampFactor(i));
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int data_to_skip = rows_to_skip * GetComponentStride(i);
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// Change our own data buffer pointers so we can pass them to the
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// callback.
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databuf_[i] += data_to_skip;
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}
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int scanlines_to_copy = GetImageScanlinesPerImcuRow() - skip;
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(*fn)(opaque, databuf_, databuf_strides_, scanlines_to_copy);
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// Now change them back.
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for (int i = 0; i < num_outbufs_; ++i) {
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int rows_to_skip = DivideAndRoundDown(skip, GetVertSubSampFactor(i));
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int data_to_skip = rows_to_skip * GetComponentStride(i);
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databuf_[i] -= data_to_skip;
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}
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lines_left -= scanlines_to_copy;
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}
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}
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// Read full MCUs until we get to the crop point.
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for (; lines_left >= GetImageScanlinesPerImcuRow();
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lines_left -= GetImageScanlinesPerImcuRow()) {
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if (!DecodeImcuRow()) {
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FinishDecode();
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return LIBYUV_FALSE;
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}
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(*fn)(opaque, databuf_, databuf_strides_, GetImageScanlinesPerImcuRow());
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}
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if (lines_left > 0) {
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// Have a partial iMCU row left over to decode.
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if (!DecodeImcuRow()) {
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FinishDecode();
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return LIBYUV_FALSE;
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}
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(*fn)(opaque, databuf_, databuf_strides_, lines_left);
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}
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return FinishDecode();
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}
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void init_source(j_decompress_ptr cinfo) {
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fill_input_buffer(cinfo);
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}
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boolean fill_input_buffer(j_decompress_ptr cinfo) {
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BufferVector* buf_vec = reinterpret_cast<BufferVector*>(cinfo->client_data);
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if (buf_vec->pos >= buf_vec->len) {
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assert(0 && "No more data");
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// ERROR: No more data
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return FALSE;
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}
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cinfo->src->next_input_byte = buf_vec->buffers[buf_vec->pos].data;
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cinfo->src->bytes_in_buffer = buf_vec->buffers[buf_vec->pos].len;
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++buf_vec->pos;
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return TRUE;
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}
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void skip_input_data(j_decompress_ptr cinfo, long num_bytes) { // NOLINT
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cinfo->src->next_input_byte += num_bytes;
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}
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void term_source(j_decompress_ptr cinfo) {
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(void)cinfo; // Nothing to do.
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}
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#ifdef HAVE_SETJMP
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void ErrorHandler(j_common_ptr cinfo) {
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// This is called when a jpeglib command experiences an error. Unfortunately
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// jpeglib's error handling model is not very flexible, because it expects the
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// error handler to not return--i.e., it wants the program to terminate. To
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// recover from errors we use setjmp() as shown in their example. setjmp() is
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// C's implementation for the "call with current continuation" functionality
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// seen in some functional programming languages.
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// A formatted message can be output, but is unsafe for release.
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#ifdef DEBUG
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char buf[JMSG_LENGTH_MAX];
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(*cinfo->err->format_message)(cinfo, buf);
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// ERROR: Error in jpeglib: buf
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#endif
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SetJmpErrorMgr* mgr = reinterpret_cast<SetJmpErrorMgr*>(cinfo->err);
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// This rewinds the call stack to the point of the corresponding setjmp()
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// and causes it to return (for a second time) with value 1.
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longjmp(mgr->setjmp_buffer, 1);
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}
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// Suppress fprintf warnings.
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void OutputHandler(j_common_ptr cinfo) {
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(void)cinfo;
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}
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#endif // HAVE_SETJMP
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void MJpegDecoder::AllocOutputBuffers(int num_outbufs) {
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if (num_outbufs != num_outbufs_) {
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// We could perhaps optimize this case to resize the output buffers without
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// necessarily having to delete and recreate each one, but it's not worth
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// it.
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DestroyOutputBuffers();
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scanlines_ = new uint8**[num_outbufs];
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scanlines_sizes_ = new int[num_outbufs];
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databuf_ = new uint8*[num_outbufs];
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databuf_strides_ = new int[num_outbufs];
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for (int i = 0; i < num_outbufs; ++i) {
|
|
scanlines_[i] = NULL;
|
|
scanlines_sizes_[i] = 0;
|
|
databuf_[i] = NULL;
|
|
databuf_strides_[i] = 0;
|
|
}
|
|
|
|
num_outbufs_ = num_outbufs;
|
|
}
|
|
}
|
|
|
|
void MJpegDecoder::DestroyOutputBuffers() {
|
|
for (int i = 0; i < num_outbufs_; ++i) {
|
|
delete[] scanlines_[i];
|
|
delete[] databuf_[i];
|
|
}
|
|
delete[] scanlines_;
|
|
delete[] databuf_;
|
|
delete[] scanlines_sizes_;
|
|
delete[] databuf_strides_;
|
|
scanlines_ = NULL;
|
|
databuf_ = NULL;
|
|
scanlines_sizes_ = NULL;
|
|
databuf_strides_ = NULL;
|
|
num_outbufs_ = 0;
|
|
}
|
|
|
|
// JDCT_IFAST and do_block_smoothing improve performance substantially.
|
|
LIBYUV_BOOL MJpegDecoder::StartDecode() {
|
|
decompress_struct_->raw_data_out = TRUE;
|
|
decompress_struct_->dct_method = JDCT_IFAST; // JDCT_ISLOW is default
|
|
decompress_struct_->dither_mode = JDITHER_NONE;
|
|
// Not applicable to 'raw':
|
|
decompress_struct_->do_fancy_upsampling = (boolean)(LIBYUV_FALSE);
|
|
// Only for buffered mode:
|
|
decompress_struct_->enable_2pass_quant = (boolean)(LIBYUV_FALSE);
|
|
// Blocky but fast:
|
|
decompress_struct_->do_block_smoothing = (boolean)(LIBYUV_FALSE);
|
|
|
|
if (!jpeg_start_decompress(decompress_struct_)) {
|
|
// ERROR: Couldn't start JPEG decompressor";
|
|
return LIBYUV_FALSE;
|
|
}
|
|
return LIBYUV_TRUE;
|
|
}
|
|
|
|
LIBYUV_BOOL MJpegDecoder::FinishDecode() {
|
|
// jpeglib considers it an error if we finish without decoding the whole
|
|
// image, so we call "abort" rather than "finish".
|
|
jpeg_abort_decompress(decompress_struct_);
|
|
return LIBYUV_TRUE;
|
|
}
|
|
|
|
void MJpegDecoder::SetScanlinePointers(uint8** data) {
|
|
for (int i = 0; i < num_outbufs_; ++i) {
|
|
uint8* data_i = data[i];
|
|
for (int j = 0; j < scanlines_sizes_[i]; ++j) {
|
|
scanlines_[i][j] = data_i;
|
|
data_i += GetComponentStride(i);
|
|
}
|
|
}
|
|
}
|
|
|
|
inline LIBYUV_BOOL MJpegDecoder::DecodeImcuRow() {
|
|
return (unsigned int)(GetImageScanlinesPerImcuRow()) ==
|
|
jpeg_read_raw_data(decompress_struct_, scanlines_,
|
|
GetImageScanlinesPerImcuRow());
|
|
}
|
|
|
|
// The helper function which recognizes the jpeg sub-sampling type.
|
|
JpegSubsamplingType MJpegDecoder::JpegSubsamplingTypeHelper(
|
|
int* subsample_x,
|
|
int* subsample_y,
|
|
int number_of_components) {
|
|
if (number_of_components == 3) { // Color images.
|
|
if (subsample_x[0] == 1 && subsample_y[0] == 1 && subsample_x[1] == 2 &&
|
|
subsample_y[1] == 2 && subsample_x[2] == 2 && subsample_y[2] == 2) {
|
|
return kJpegYuv420;
|
|
} else if (subsample_x[0] == 1 && subsample_y[0] == 1 &&
|
|
subsample_x[1] == 2 && subsample_y[1] == 1 &&
|
|
subsample_x[2] == 2 && subsample_y[2] == 1) {
|
|
return kJpegYuv422;
|
|
} else if (subsample_x[0] == 1 && subsample_y[0] == 1 &&
|
|
subsample_x[1] == 1 && subsample_y[1] == 1 &&
|
|
subsample_x[2] == 1 && subsample_y[2] == 1) {
|
|
return kJpegYuv444;
|
|
}
|
|
} else if (number_of_components == 1) { // Grey-scale images.
|
|
if (subsample_x[0] == 1 && subsample_y[0] == 1) {
|
|
return kJpegYuv400;
|
|
}
|
|
}
|
|
return kJpegUnknown;
|
|
}
|
|
|
|
} // namespace libyuv
|
|
#endif // HAVE_JPEG
|