ref: 3c9a424e6e9c70afc2f7586093d440ec3fba7dfe
dir: /third_party/libyuv/source/mjpeg_decoder.cc/
/*
* Copyright 2012 The LibYuv Project Authors. All rights reserved.
*
* Use of this source code is governed by a BSD-style license
* that can be found in the LICENSE file in the root of the source
* tree. An additional intellectual property rights grant can be found
* in the file PATENTS. All contributing project authors may
* be found in the AUTHORS file in the root of the source tree.
*/
#include "libyuv/mjpeg_decoder.h"
#ifdef HAVE_JPEG
#include <assert.h>
#if !defined(__pnacl__) && !defined(__CLR_VER) && \
!defined(COVERAGE_ENABLED) && !defined(TARGET_IPHONE_SIMULATOR)
// Must be included before jpeglib.
#include <setjmp.h>
#define HAVE_SETJMP
#if defined(_MSC_VER)
// disable warning 4324: structure was padded due to __declspec(align())
#pragma warning(disable:4324)
#endif
#endif
struct FILE; // For jpeglib.h.
// C++ build requires extern C for jpeg internals.
#ifdef __cplusplus
extern "C" {
#endif
#include <jpeglib.h>
#ifdef __cplusplus
} // extern "C"
#endif
#include "libyuv/planar_functions.h" // For CopyPlane().
namespace libyuv {
#ifdef HAVE_SETJMP
struct SetJmpErrorMgr {
jpeg_error_mgr base; // Must be at the top
jmp_buf setjmp_buffer;
};
#endif
const int MJpegDecoder::kColorSpaceUnknown = JCS_UNKNOWN;
const int MJpegDecoder::kColorSpaceGrayscale = JCS_GRAYSCALE;
const int MJpegDecoder::kColorSpaceRgb = JCS_RGB;
const int MJpegDecoder::kColorSpaceYCbCr = JCS_YCbCr;
const int MJpegDecoder::kColorSpaceCMYK = JCS_CMYK;
const int MJpegDecoder::kColorSpaceYCCK = JCS_YCCK;
// Methods that are passed to jpeglib.
boolean fill_input_buffer(jpeg_decompress_struct* cinfo);
void init_source(jpeg_decompress_struct* cinfo);
void skip_input_data(jpeg_decompress_struct* cinfo,
long num_bytes); // NOLINT
void term_source(jpeg_decompress_struct* cinfo);
void ErrorHandler(jpeg_common_struct* cinfo);
MJpegDecoder::MJpegDecoder()
: has_scanline_padding_(LIBYUV_FALSE),
num_outbufs_(0),
scanlines_(NULL),
scanlines_sizes_(NULL),
databuf_(NULL),
databuf_strides_(NULL) {
decompress_struct_ = new jpeg_decompress_struct;
source_mgr_ = new jpeg_source_mgr;
#ifdef HAVE_SETJMP
error_mgr_ = new SetJmpErrorMgr;
decompress_struct_->err = jpeg_std_error(&error_mgr_->base);
// Override standard exit()-based error handler.
error_mgr_->base.error_exit = &ErrorHandler;
#endif
decompress_struct_->client_data = NULL;
source_mgr_->init_source = &init_source;
source_mgr_->fill_input_buffer = &fill_input_buffer;
source_mgr_->skip_input_data = &skip_input_data;
source_mgr_->resync_to_restart = &jpeg_resync_to_restart;
source_mgr_->term_source = &term_source;
jpeg_create_decompress(decompress_struct_);
decompress_struct_->src = source_mgr_;
buf_vec_.buffers = &buf_;
buf_vec_.len = 1;
}
MJpegDecoder::~MJpegDecoder() {
jpeg_destroy_decompress(decompress_struct_);
delete decompress_struct_;
delete source_mgr_;
#ifdef HAVE_SETJMP
delete error_mgr_;
#endif
DestroyOutputBuffers();
}
LIBYUV_BOOL MJpegDecoder::LoadFrame(const uint8* src, size_t src_len) {
if (!ValidateJpeg(src, src_len)) {
return LIBYUV_FALSE;
}
buf_.data = src;
buf_.len = static_cast<int>(src_len);
buf_vec_.pos = 0;
decompress_struct_->client_data = &buf_vec_;
#ifdef HAVE_SETJMP
if (setjmp(error_mgr_->setjmp_buffer)) {
// We called jpeg_read_header, it experienced an error, and we called
// longjmp() and rewound the stack to here. Return error.
return LIBYUV_FALSE;
}
#endif
if (jpeg_read_header(decompress_struct_, TRUE) != JPEG_HEADER_OK) {
// ERROR: Bad MJPEG header
return LIBYUV_FALSE;
}
AllocOutputBuffers(GetNumComponents());
for (int i = 0; i < num_outbufs_; ++i) {
int scanlines_size = GetComponentScanlinesPerImcuRow(i);
if (scanlines_sizes_[i] != scanlines_size) {
if (scanlines_[i]) {
delete scanlines_[i];
}
scanlines_[i] = new uint8* [scanlines_size];
scanlines_sizes_[i] = scanlines_size;
}
// We allocate padding for the final scanline to pad it up to DCTSIZE bytes
// to avoid memory errors, since jpeglib only reads full MCUs blocks. For
// the preceding scanlines, the padding is not needed/wanted because the
// following addresses will already be valid (they are the initial bytes of
// the next scanline) and will be overwritten when jpeglib writes out that
// next scanline.
int databuf_stride = GetComponentStride(i);
int databuf_size = scanlines_size * databuf_stride;
if (databuf_strides_[i] != databuf_stride) {
if (databuf_[i]) {
delete databuf_[i];
}
databuf_[i] = new uint8[databuf_size];
databuf_strides_[i] = databuf_stride;
}
if (GetComponentStride(i) != GetComponentWidth(i)) {
has_scanline_padding_ = LIBYUV_TRUE;
}
}
return LIBYUV_TRUE;
}
static int DivideAndRoundUp(int numerator, int denominator) {
return (numerator + denominator - 1) / denominator;
}
static int DivideAndRoundDown(int numerator, int denominator) {
return numerator / denominator;
}
// Returns width of the last loaded frame.
int MJpegDecoder::GetWidth() {
return decompress_struct_->image_width;
}
// Returns height of the last loaded frame.
int MJpegDecoder::GetHeight() {
return decompress_struct_->image_height;
}
// Returns format of the last loaded frame. The return value is one of the
// kColorSpace* constants.
int MJpegDecoder::GetColorSpace() {
return decompress_struct_->jpeg_color_space;
}
// Number of color components in the color space.
int MJpegDecoder::GetNumComponents() {
return decompress_struct_->num_components;
}
// Sample factors of the n-th component.
int MJpegDecoder::GetHorizSampFactor(int component) {
return decompress_struct_->comp_info[component].h_samp_factor;
}
int MJpegDecoder::GetVertSampFactor(int component) {
return decompress_struct_->comp_info[component].v_samp_factor;
}
int MJpegDecoder::GetHorizSubSampFactor(int component) {
return decompress_struct_->max_h_samp_factor /
GetHorizSampFactor(component);
}
int MJpegDecoder::GetVertSubSampFactor(int component) {
return decompress_struct_->max_v_samp_factor /
GetVertSampFactor(component);
}
int MJpegDecoder::GetImageScanlinesPerImcuRow() {
return decompress_struct_->max_v_samp_factor * DCTSIZE;
}
int MJpegDecoder::GetComponentScanlinesPerImcuRow(int component) {
int vs = GetVertSubSampFactor(component);
return DivideAndRoundUp(GetImageScanlinesPerImcuRow(), vs);
}
int MJpegDecoder::GetComponentWidth(int component) {
int hs = GetHorizSubSampFactor(component);
return DivideAndRoundUp(GetWidth(), hs);
}
int MJpegDecoder::GetComponentHeight(int component) {
int vs = GetVertSubSampFactor(component);
return DivideAndRoundUp(GetHeight(), vs);
}
// Get width in bytes padded out to a multiple of DCTSIZE
int MJpegDecoder::GetComponentStride(int component) {
return (GetComponentWidth(component) + DCTSIZE - 1) & ~(DCTSIZE - 1);
}
int MJpegDecoder::GetComponentSize(int component) {
return GetComponentWidth(component) * GetComponentHeight(component);
}
LIBYUV_BOOL MJpegDecoder::UnloadFrame() {
#ifdef HAVE_SETJMP
if (setjmp(error_mgr_->setjmp_buffer)) {
// We called jpeg_abort_decompress, it experienced an error, and we called
// longjmp() and rewound the stack to here. Return error.
return LIBYUV_FALSE;
}
#endif
jpeg_abort_decompress(decompress_struct_);
return LIBYUV_TRUE;
}
// TODO(fbarchard): Allow rectangle to be specified: x, y, width, height.
LIBYUV_BOOL MJpegDecoder::DecodeToBuffers(
uint8** planes, int dst_width, int dst_height) {
if (dst_width != GetWidth() ||
dst_height > GetHeight()) {
// ERROR: Bad dimensions
return LIBYUV_FALSE;
}
#ifdef HAVE_SETJMP
if (setjmp(error_mgr_->setjmp_buffer)) {
// We called into jpeglib, it experienced an error sometime during this
// function call, and we called longjmp() and rewound the stack to here.
// Return error.
return LIBYUV_FALSE;
}
#endif
if (!StartDecode()) {
return LIBYUV_FALSE;
}
SetScanlinePointers(databuf_);
int lines_left = dst_height;
// Compute amount of lines to skip to implement vertical crop.
// TODO(fbarchard): Ensure skip is a multiple of maximum component
// subsample. ie 2
int skip = (GetHeight() - dst_height) / 2;
if (skip > 0) {
// There is no API to skip lines in the output data, so we read them
// into the temp buffer.
while (skip >= GetImageScanlinesPerImcuRow()) {
if (!DecodeImcuRow()) {
FinishDecode();
return LIBYUV_FALSE;
}
skip -= GetImageScanlinesPerImcuRow();
}
if (skip > 0) {
// Have a partial iMCU row left over to skip. Must read it and then
// copy the parts we want into the destination.
if (!DecodeImcuRow()) {
FinishDecode();
return LIBYUV_FALSE;
}
for (int i = 0; i < num_outbufs_; ++i) {
// TODO(fbarchard): Compute skip to avoid this
assert(skip % GetVertSubSampFactor(i) == 0);
int rows_to_skip =
DivideAndRoundDown(skip, GetVertSubSampFactor(i));
int scanlines_to_copy = GetComponentScanlinesPerImcuRow(i) -
rows_to_skip;
int data_to_skip = rows_to_skip * GetComponentStride(i);
CopyPlane(databuf_[i] + data_to_skip, GetComponentStride(i),
planes[i], GetComponentWidth(i),
GetComponentWidth(i), scanlines_to_copy);
planes[i] += scanlines_to_copy * GetComponentWidth(i);
}
lines_left -= (GetImageScanlinesPerImcuRow() - skip);
}
}
// Read full MCUs but cropped horizontally
for (; lines_left > GetImageScanlinesPerImcuRow();
lines_left -= GetImageScanlinesPerImcuRow()) {
if (!DecodeImcuRow()) {
FinishDecode();
return LIBYUV_FALSE;
}
for (int i = 0; i < num_outbufs_; ++i) {
int scanlines_to_copy = GetComponentScanlinesPerImcuRow(i);
CopyPlane(databuf_[i], GetComponentStride(i),
planes[i], GetComponentWidth(i),
GetComponentWidth(i), scanlines_to_copy);
planes[i] += scanlines_to_copy * GetComponentWidth(i);
}
}
if (lines_left > 0) {
// Have a partial iMCU row left over to decode.
if (!DecodeImcuRow()) {
FinishDecode();
return LIBYUV_FALSE;
}
for (int i = 0; i < num_outbufs_; ++i) {
int scanlines_to_copy =
DivideAndRoundUp(lines_left, GetVertSubSampFactor(i));
CopyPlane(databuf_[i], GetComponentStride(i),
planes[i], GetComponentWidth(i),
GetComponentWidth(i), scanlines_to_copy);
planes[i] += scanlines_to_copy * GetComponentWidth(i);
}
}
return FinishDecode();
}
LIBYUV_BOOL MJpegDecoder::DecodeToCallback(CallbackFunction fn, void* opaque,
int dst_width, int dst_height) {
if (dst_width != GetWidth() ||
dst_height > GetHeight()) {
// ERROR: Bad dimensions
return LIBYUV_FALSE;
}
#ifdef HAVE_SETJMP
if (setjmp(error_mgr_->setjmp_buffer)) {
// We called into jpeglib, it experienced an error sometime during this
// function call, and we called longjmp() and rewound the stack to here.
// Return error.
return LIBYUV_FALSE;
}
#endif
if (!StartDecode()) {
return LIBYUV_FALSE;
}
SetScanlinePointers(databuf_);
int lines_left = dst_height;
// TODO(fbarchard): Compute amount of lines to skip to implement vertical crop
int skip = (GetHeight() - dst_height) / 2;
if (skip > 0) {
while (skip >= GetImageScanlinesPerImcuRow()) {
if (!DecodeImcuRow()) {
FinishDecode();
return LIBYUV_FALSE;
}
skip -= GetImageScanlinesPerImcuRow();
}
if (skip > 0) {
// Have a partial iMCU row left over to skip.
if (!DecodeImcuRow()) {
FinishDecode();
return LIBYUV_FALSE;
}
for (int i = 0; i < num_outbufs_; ++i) {
// TODO(fbarchard): Compute skip to avoid this
assert(skip % GetVertSubSampFactor(i) == 0);
int rows_to_skip = DivideAndRoundDown(skip, GetVertSubSampFactor(i));
int data_to_skip = rows_to_skip * GetComponentStride(i);
// Change our own data buffer pointers so we can pass them to the
// callback.
databuf_[i] += data_to_skip;
}
int scanlines_to_copy = GetImageScanlinesPerImcuRow() - skip;
(*fn)(opaque, databuf_, databuf_strides_, scanlines_to_copy);
// Now change them back.
for (int i = 0; i < num_outbufs_; ++i) {
int rows_to_skip = DivideAndRoundDown(skip, GetVertSubSampFactor(i));
int data_to_skip = rows_to_skip * GetComponentStride(i);
databuf_[i] -= data_to_skip;
}
lines_left -= scanlines_to_copy;
}
}
// Read full MCUs until we get to the crop point.
for (; lines_left >= GetImageScanlinesPerImcuRow();
lines_left -= GetImageScanlinesPerImcuRow()) {
if (!DecodeImcuRow()) {
FinishDecode();
return LIBYUV_FALSE;
}
(*fn)(opaque, databuf_, databuf_strides_, GetImageScanlinesPerImcuRow());
}
if (lines_left > 0) {
// Have a partial iMCU row left over to decode.
if (!DecodeImcuRow()) {
FinishDecode();
return LIBYUV_FALSE;
}
(*fn)(opaque, databuf_, databuf_strides_, lines_left);
}
return FinishDecode();
}
void init_source(j_decompress_ptr cinfo) {
fill_input_buffer(cinfo);
}
boolean fill_input_buffer(j_decompress_ptr cinfo) {
BufferVector* buf_vec = reinterpret_cast<BufferVector*>(cinfo->client_data);
if (buf_vec->pos >= buf_vec->len) {
assert(0 && "No more data");
// ERROR: No more data
return FALSE;
}
cinfo->src->next_input_byte = buf_vec->buffers[buf_vec->pos].data;
cinfo->src->bytes_in_buffer = buf_vec->buffers[buf_vec->pos].len;
++buf_vec->pos;
return TRUE;
}
void skip_input_data(j_decompress_ptr cinfo,
long num_bytes) { // NOLINT
cinfo->src->next_input_byte += num_bytes;
}
void term_source(j_decompress_ptr cinfo) {
// Nothing to do.
}
#ifdef HAVE_SETJMP
void ErrorHandler(j_common_ptr cinfo) {
// This is called when a jpeglib command experiences an error. Unfortunately
// jpeglib's error handling model is not very flexible, because it expects the
// error handler to not return--i.e., it wants the program to terminate. To
// recover from errors we use setjmp() as shown in their example. setjmp() is
// C's implementation for the "call with current continuation" functionality
// seen in some functional programming languages.
// A formatted message can be output, but is unsafe for release.
#ifdef DEBUG
char buf[JMSG_LENGTH_MAX];
(*cinfo->err->format_message)(cinfo, buf);
// ERROR: Error in jpeglib: buf
#endif
SetJmpErrorMgr* mgr = reinterpret_cast<SetJmpErrorMgr*>(cinfo->err);
// This rewinds the call stack to the point of the corresponding setjmp()
// and causes it to return (for a second time) with value 1.
longjmp(mgr->setjmp_buffer, 1);
}
#endif
void MJpegDecoder::AllocOutputBuffers(int num_outbufs) {
if (num_outbufs != num_outbufs_) {
// We could perhaps optimize this case to resize the output buffers without
// necessarily having to delete and recreate each one, but it's not worth
// it.
DestroyOutputBuffers();
scanlines_ = new uint8** [num_outbufs];
scanlines_sizes_ = new int[num_outbufs];
databuf_ = new uint8* [num_outbufs];
databuf_strides_ = new int[num_outbufs];
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