| Index: gfx/codec/jpeg_codec.cc
 | 
| ===================================================================
 | 
| --- gfx/codec/jpeg_codec.cc	(revision 73487)
 | 
| +++ gfx/codec/jpeg_codec.cc	(working copy)
 | 
| @@ -1,535 +0,0 @@
 | 
| -// Copyright (c) 2006-2008 The Chromium Authors. All rights reserved.
 | 
| -// Use of this source code is governed by a BSD-style license that can be
 | 
| -// found in the LICENSE file.
 | 
| -
 | 
| -#include "gfx/codec/jpeg_codec.h"
 | 
| -
 | 
| -#include <setjmp.h>
 | 
| -
 | 
| -#include "base/logging.h"
 | 
| -#include "base/scoped_ptr.h"
 | 
| -#include "third_party/skia/include/core/SkBitmap.h"
 | 
| -#include "third_party/skia/include/core/SkColorPriv.h"
 | 
| -
 | 
| -extern "C" {
 | 
| -#if defined(USE_SYSTEM_LIBJPEG)
 | 
| -#include <jpeglib.h>
 | 
| -#else
 | 
| -#include "jpeglib.h"
 | 
| -#endif
 | 
| -}
 | 
| -
 | 
| -namespace gfx {
 | 
| -
 | 
| -// Encoder/decoder shared stuff ------------------------------------------------
 | 
| -
 | 
| -namespace {
 | 
| -
 | 
| -// used to pass error info through the JPEG library
 | 
| -struct CoderErrorMgr {
 | 
| -  jpeg_error_mgr pub;
 | 
| -  jmp_buf setjmp_buffer;
 | 
| -};
 | 
| -
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| -void ErrorExit(jpeg_common_struct* cinfo) {
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| -  CoderErrorMgr *err = reinterpret_cast<CoderErrorMgr*>(cinfo->err);
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| -
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| -  // Return control to the setjmp point.
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| -  longjmp(err->setjmp_buffer, false);
 | 
| -}
 | 
| -
 | 
| -}  // namespace
 | 
| -
 | 
| -// Encoder ---------------------------------------------------------------------
 | 
| -//
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| -// This code is based on nsJPEGEncoder from Mozilla.
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| -// Copyright 2005 Google Inc. (Brett Wilson, contributor)
 | 
| -
 | 
| -namespace {
 | 
| -
 | 
| -// Initial size for the output buffer in the JpegEncoderState below.
 | 
| -static const int initial_output_buffer_size = 8192;
 | 
| -
 | 
| -struct JpegEncoderState {
 | 
| -  explicit JpegEncoderState(std::vector<unsigned char>* o)
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| -      : out(o),
 | 
| -        image_buffer_used(0) {
 | 
| -  }
 | 
| -
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| -  // Output buffer, of which 'image_buffer_used' bytes are actually used (this
 | 
| -  // will often be less than the actual size of the vector because we size it
 | 
| -  // so that libjpeg can write directly into it.
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| -  std::vector<unsigned char>* out;
 | 
| -
 | 
| -  // Number of bytes in the 'out' buffer that are actually used (see above).
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| -  size_t image_buffer_used;
 | 
| -};
 | 
| -
 | 
| -// Initializes the JpegEncoderState for encoding, and tells libjpeg about where
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| -// the output buffer is.
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| -//
 | 
| -// From the JPEG library:
 | 
| -//  "Initialize destination. This is called by jpeg_start_compress() before
 | 
| -//   any data is actually written. It must initialize next_output_byte and
 | 
| -//   free_in_buffer. free_in_buffer must be initialized to a positive value."
 | 
| -void InitDestination(jpeg_compress_struct* cinfo) {
 | 
| -  JpegEncoderState* state = static_cast<JpegEncoderState*>(cinfo->client_data);
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| -  DCHECK(state->image_buffer_used == 0) << "initializing after use";
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| -
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| -  state->out->resize(initial_output_buffer_size);
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| -  state->image_buffer_used = 0;
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| -
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| -  cinfo->dest->next_output_byte = &(*state->out)[0];
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| -  cinfo->dest->free_in_buffer = initial_output_buffer_size;
 | 
| -}
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| -
 | 
| -// Resize the buffer that we give to libjpeg and update our and its state.
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| -//
 | 
| -// From the JPEG library:
 | 
| -//  "Callback used by libjpeg whenever the buffer has filled (free_in_buffer
 | 
| -//   reaches zero). In typical applications, it should write out the *entire*
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| -//   buffer (use the saved start address and buffer length; ignore the current
 | 
| -//   state of next_output_byte and free_in_buffer). Then reset the pointer &
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| -//   count to the start of the buffer, and return TRUE indicating that the
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| -//   buffer has been dumped. free_in_buffer must be set to a positive value
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| -//   when TRUE is returned. A FALSE return should only be used when I/O
 | 
| -//   suspension is desired (this operating mode is discussed in the next
 | 
| -//   section)."
 | 
| -boolean EmptyOutputBuffer(jpeg_compress_struct* cinfo) {
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| -  JpegEncoderState* state = static_cast<JpegEncoderState*>(cinfo->client_data);
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| -
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| -  // note the new size, the buffer is full
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| -  state->image_buffer_used = state->out->size();
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| -
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| -  // expand buffer, just double size each time
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| -  state->out->resize(state->out->size() * 2);
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| -
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| -  // tell libjpeg where to write the next data
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| -  cinfo->dest->next_output_byte = &(*state->out)[state->image_buffer_used];
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| -  cinfo->dest->free_in_buffer = state->out->size() - state->image_buffer_used;
 | 
| -  return 1;
 | 
| -}
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| -
 | 
| -// Cleans up the JpegEncoderState to prepare for returning in the final form.
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| -//
 | 
| -// From the JPEG library:
 | 
| -//  "Terminate destination --- called by jpeg_finish_compress() after all data
 | 
| -//   has been written. In most applications, this must flush any data
 | 
| -//   remaining in the buffer. Use either next_output_byte or free_in_buffer to
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| -//   determine how much data is in the buffer."
 | 
| -void TermDestination(jpeg_compress_struct* cinfo) {
 | 
| -  JpegEncoderState* state = static_cast<JpegEncoderState*>(cinfo->client_data);
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| -  DCHECK(state->out->size() >= state->image_buffer_used);
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| -
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| -  // update the used byte based on the next byte libjpeg would write to
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| -  state->image_buffer_used = cinfo->dest->next_output_byte - &(*state->out)[0];
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| -  DCHECK(state->image_buffer_used < state->out->size()) <<
 | 
| -    "JPEG library busted, got a bad image buffer size";
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| -
 | 
| -  // update our buffer so that it exactly encompases the desired data
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| -  state->out->resize(state->image_buffer_used);
 | 
| -}
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| -
 | 
| -// Converts RGBA to RGB (removing the alpha values) to prepare to send data to
 | 
| -// libjpeg. This converts one row of data in rgba with the given width in
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| -// pixels the the given rgb destination buffer (which should have enough space
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| -// reserved for the final data).
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| -void StripAlpha(const unsigned char* rgba, int pixel_width, unsigned char* rgb)
 | 
| -{
 | 
| -  for (int x = 0; x < pixel_width; x++) {
 | 
| -    const unsigned char* pixel_in = &rgba[x * 4];
 | 
| -    unsigned char* pixel_out = &rgb[x * 3];
 | 
| -    pixel_out[0] = pixel_in[0];
 | 
| -    pixel_out[1] = pixel_in[1];
 | 
| -    pixel_out[2] = pixel_in[2];
 | 
| -  }
 | 
| -}
 | 
| -
 | 
| -// Converts BGRA to RGB by reordering the color components and dropping the
 | 
| -// alpha. This converts  one row of data in rgba with the given width in
 | 
| -// pixels the the given rgb destination buffer (which should have enough space
 | 
| -// reserved for the final data).
 | 
| -void BGRAtoRGB(const unsigned char* bgra, int pixel_width, unsigned char* rgb)
 | 
| -{
 | 
| -  for (int x = 0; x < pixel_width; x++) {
 | 
| -    const unsigned char* pixel_in = &bgra[x * 4];
 | 
| -    unsigned char* pixel_out = &rgb[x * 3];
 | 
| -    pixel_out[0] = pixel_in[2];
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| -    pixel_out[1] = pixel_in[1];
 | 
| -    pixel_out[2] = pixel_in[0];
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| -  }
 | 
| -}
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| -
 | 
| -// This class destroys the given jpeg_compress object when it goes out of
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| -// scope. It simplifies the error handling in Encode (and even applies to the
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| -// success case).
 | 
| -class CompressDestroyer {
 | 
| - public:
 | 
| -  CompressDestroyer() : cinfo_(NULL) {
 | 
| -  }
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| -  ~CompressDestroyer() {
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| -    DestroyManagedObject();
 | 
| -  }
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| -  void SetManagedObject(jpeg_compress_struct* ci) {
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| -    DestroyManagedObject();
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| -    cinfo_ = ci;
 | 
| -  }
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| -  void DestroyManagedObject() {
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| -    if (cinfo_) {
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| -      jpeg_destroy_compress(cinfo_);
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| -      cinfo_ = NULL;
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| -    }
 | 
| -  }
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| - private:
 | 
| -  jpeg_compress_struct* cinfo_;
 | 
| -};
 | 
| -
 | 
| -}  // namespace
 | 
| -
 | 
| -bool JPEGCodec::Encode(const unsigned char* input, ColorFormat format,
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| -                       int w, int h, int row_byte_width,
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| -                       int quality, std::vector<unsigned char>* output) {
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| -  jpeg_compress_struct cinfo;
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| -  CompressDestroyer destroyer;
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| -  destroyer.SetManagedObject(&cinfo);
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| -  output->clear();
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| -
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| -  // We set up the normal JPEG error routines, then override error_exit.
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| -  // This must be done before the call to create_compress.
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| -  CoderErrorMgr errmgr;
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| -  cinfo.err = jpeg_std_error(&errmgr.pub);
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| -  errmgr.pub.error_exit = ErrorExit;
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| -  // Establish the setjmp return context for ErrorExit to use.
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| -  if (setjmp(errmgr.setjmp_buffer)) {
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| -    // If we get here, the JPEG code has signaled an error.
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| -    // MSDN notes: "if you intend your code to be portable, do not rely on
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| -    // correct destruction of frame-based objects when executing a nonlocal
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| -    // goto using a call to longjmp."  So we delete the CompressDestroyer's
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| -    // object manually instead.
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| -    destroyer.DestroyManagedObject();
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| -    return false;
 | 
| -  }
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| -
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| -  // The destroyer will destroy() cinfo on exit.
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| -  jpeg_create_compress(&cinfo);
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| -
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| -  cinfo.image_width = w;
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| -  cinfo.image_height = h;
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| -  cinfo.input_components = 3;
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| -  cinfo.in_color_space = JCS_RGB;
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| -  cinfo.data_precision = 8;
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| -
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| -  jpeg_set_defaults(&cinfo);
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| -  jpeg_set_quality(&cinfo, quality, 1);  // quality here is 0-100
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| -
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| -  // set up the destination manager
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| -  jpeg_destination_mgr destmgr;
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| -  destmgr.init_destination = InitDestination;
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| -  destmgr.empty_output_buffer = EmptyOutputBuffer;
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| -  destmgr.term_destination = TermDestination;
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| -  cinfo.dest = &destmgr;
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| -
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| -  JpegEncoderState state(output);
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| -  cinfo.client_data = &state;
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| -
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| -  jpeg_start_compress(&cinfo, 1);
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| -
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| -  // feed it the rows, doing necessary conversions for the color format
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| -  if (format == FORMAT_RGB) {
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| -    // no conversion necessary
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| -    while (cinfo.next_scanline < cinfo.image_height) {
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| -      const unsigned char* row = &input[cinfo.next_scanline * row_byte_width];
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| -      jpeg_write_scanlines(&cinfo, const_cast<unsigned char**>(&row), 1);
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| -    }
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| -  } else {
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| -    // get the correct format converter
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| -    void (*converter)(const unsigned char* in, int w, unsigned char* rgb);
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| -    if (format == FORMAT_RGBA ||
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| -        (format == FORMAT_SkBitmap && SK_R32_SHIFT == 0)) {
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| -      converter = StripAlpha;
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| -    } else if (format == FORMAT_BGRA ||
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| -               (format == FORMAT_SkBitmap && SK_B32_SHIFT == 0)) {
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| -      converter = BGRAtoRGB;
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| -    } else {
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| -      NOTREACHED() << "Invalid pixel format";
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| -      return false;
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| -    }
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| -
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| -    // output row after converting
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| -    unsigned char* row = new unsigned char[w * 3];
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| -
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| -    while (cinfo.next_scanline < cinfo.image_height) {
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| -      converter(&input[cinfo.next_scanline * row_byte_width], w, row);
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| -      jpeg_write_scanlines(&cinfo, &row, 1);
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| -    }
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| -    delete[] row;
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| -  }
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| -
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| -  jpeg_finish_compress(&cinfo);
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| -  return true;
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| -}
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| -
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| -// Decoder --------------------------------------------------------------------
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| -
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| -namespace {
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| -
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| -struct JpegDecoderState {
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| -  JpegDecoderState(const unsigned char* in, size_t len)
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| -      : input_buffer(in), input_buffer_length(len) {
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| -  }
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| -
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| -  const unsigned char* input_buffer;
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| -  size_t input_buffer_length;
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| -};
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| -
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| -// Callback to initialize the source.
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| -//
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| -// From the JPEG library:
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| -//  "Initialize source. This is called by jpeg_read_header() before any data is
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| -//   actually read. May leave bytes_in_buffer set to 0 (in which case a
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| -//   fill_input_buffer() call will occur immediately)."
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| -void InitSource(j_decompress_ptr cinfo) {
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| -  JpegDecoderState* state = static_cast<JpegDecoderState*>(cinfo->client_data);
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| -  cinfo->src->next_input_byte = state->input_buffer;
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| -  cinfo->src->bytes_in_buffer = state->input_buffer_length;
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| -}
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| -
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| -// Callback to fill the buffer. Since our buffer already contains all the data,
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| -// we should never need to provide more data. If libjpeg thinks it needs more
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| -// data, our input is probably corrupt.
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| -//
 | 
| -// From the JPEG library:
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| -//  "This is called whenever bytes_in_buffer has reached zero and more data is
 | 
| -//   wanted. In typical applications, it should read fresh data into the buffer
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| -//   (ignoring the current state of next_input_byte and bytes_in_buffer), reset
 | 
| -//   the pointer & count to the start of the buffer, and return TRUE indicating
 | 
| -//   that the buffer has been reloaded. It is not necessary to fill the buffer
 | 
| -//   entirely, only to obtain at least one more byte. bytes_in_buffer MUST be
 | 
| -//   set to a positive value if TRUE is returned. A FALSE return should only
 | 
| -//   be used when I/O suspension is desired."
 | 
| -boolean FillInputBuffer(j_decompress_ptr cinfo) {
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| -  return false;
 | 
| -}
 | 
| -
 | 
| -// Skip data in the buffer. Since we have all the data at once, this operation
 | 
| -// is easy. It is not clear if this ever gets called because the JPEG library
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| -// should be able to do the skip itself (it has all the data).
 | 
| -//
 | 
| -// From the JPEG library:
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| -//  "Skip num_bytes worth of data. The buffer pointer and count should be
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| -//   advanced over num_bytes input bytes, refilling the buffer as needed. This
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| -//   is used to skip over a potentially large amount of uninteresting data
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| -//   (such as an APPn marker). In some applications it may be possible to
 | 
| -//   optimize away the reading of the skipped data, but it's not clear that
 | 
| -//   being smart is worth much trouble; large skips are uncommon.
 | 
| -//   bytes_in_buffer may be zero on return. A zero or negative skip count
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| -//   should be treated as a no-op."
 | 
| -void SkipInputData(j_decompress_ptr cinfo, long num_bytes) {
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| -  if (num_bytes > static_cast<long>(cinfo->src->bytes_in_buffer)) {
 | 
| -    // Since all our data should be in the buffer, trying to skip beyond it
 | 
| -    // means that there is some kind of error or corrupt input data. A 0 for
 | 
| -    // bytes left means it will call FillInputBuffer which will then fail.
 | 
| -    cinfo->src->next_input_byte += cinfo->src->bytes_in_buffer;
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| -    cinfo->src->bytes_in_buffer = 0;
 | 
| -  } else if (num_bytes > 0) {
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| -    cinfo->src->bytes_in_buffer -= static_cast<size_t>(num_bytes);
 | 
| -    cinfo->src->next_input_byte += num_bytes;
 | 
| -  }
 | 
| -}
 | 
| -
 | 
| -// Our source doesn't need any cleanup, so this is a NOP.
 | 
| -//
 | 
| -// From the JPEG library:
 | 
| -//  "Terminate source --- called by jpeg_finish_decompress() after all data has
 | 
| -//   been read to clean up JPEG source manager. NOT called by jpeg_abort() or
 | 
| -//   jpeg_destroy()."
 | 
| -void TermSource(j_decompress_ptr cinfo) {
 | 
| -}
 | 
| -
 | 
| -// Converts one row of rgb data to rgba data by adding a fully-opaque alpha
 | 
| -// value.
 | 
| -void AddAlpha(const unsigned char* rgb, int pixel_width, unsigned char* rgba) {
 | 
| -  for (int x = 0; x < pixel_width; x++) {
 | 
| -    const unsigned char* pixel_in = &rgb[x * 3];
 | 
| -    unsigned char* pixel_out = &rgba[x * 4];
 | 
| -    pixel_out[0] = pixel_in[0];
 | 
| -    pixel_out[1] = pixel_in[1];
 | 
| -    pixel_out[2] = pixel_in[2];
 | 
| -    pixel_out[3] = 0xff;
 | 
| -  }
 | 
| -}
 | 
| -
 | 
| -// Converts one row of RGB data to BGRA by reordering the color components and
 | 
| -// adding alpha values of 0xff.
 | 
| -void RGBtoBGRA(const unsigned char* bgra, int pixel_width, unsigned char* rgb)
 | 
| -{
 | 
| -  for (int x = 0; x < pixel_width; x++) {
 | 
| -    const unsigned char* pixel_in = &bgra[x * 3];
 | 
| -    unsigned char* pixel_out = &rgb[x * 4];
 | 
| -    pixel_out[0] = pixel_in[2];
 | 
| -    pixel_out[1] = pixel_in[1];
 | 
| -    pixel_out[2] = pixel_in[0];
 | 
| -    pixel_out[3] = 0xff;
 | 
| -  }
 | 
| -}
 | 
| -
 | 
| -// This class destroys the given jpeg_decompress object when it goes out of
 | 
| -// scope. It simplifies the error handling in Decode (and even applies to the
 | 
| -// success case).
 | 
| -class DecompressDestroyer {
 | 
| - public:
 | 
| -  DecompressDestroyer() : cinfo_(NULL) {
 | 
| -  }
 | 
| -  ~DecompressDestroyer() {
 | 
| -    DestroyManagedObject();
 | 
| -  }
 | 
| -  void SetManagedObject(jpeg_decompress_struct* ci) {
 | 
| -    DestroyManagedObject();
 | 
| -    cinfo_ = ci;
 | 
| -  }
 | 
| -  void DestroyManagedObject() {
 | 
| -    if (cinfo_) {
 | 
| -      jpeg_destroy_decompress(cinfo_);
 | 
| -      cinfo_ = NULL;
 | 
| -    }
 | 
| -  }
 | 
| - private:
 | 
| -  jpeg_decompress_struct* cinfo_;
 | 
| -};
 | 
| -
 | 
| -}  // namespace
 | 
| -
 | 
| -bool JPEGCodec::Decode(const unsigned char* input, size_t input_size,
 | 
| -                       ColorFormat format, std::vector<unsigned char>* output,
 | 
| -                       int* w, int* h) {
 | 
| -  jpeg_decompress_struct cinfo;
 | 
| -  DecompressDestroyer destroyer;
 | 
| -  destroyer.SetManagedObject(&cinfo);
 | 
| -  output->clear();
 | 
| -
 | 
| -  // We set up the normal JPEG error routines, then override error_exit.
 | 
| -  // This must be done before the call to create_decompress.
 | 
| -  CoderErrorMgr errmgr;
 | 
| -  cinfo.err = jpeg_std_error(&errmgr.pub);
 | 
| -  errmgr.pub.error_exit = ErrorExit;
 | 
| -  // Establish the setjmp return context for ErrorExit to use.
 | 
| -  if (setjmp(errmgr.setjmp_buffer)) {
 | 
| -    // If we get here, the JPEG code has signaled an error.
 | 
| -    // See note in JPEGCodec::Encode() for why we need to destroy the cinfo
 | 
| -    // manually here.
 | 
| -    destroyer.DestroyManagedObject();
 | 
| -    return false;
 | 
| -  }
 | 
| -
 | 
| -  // The destroyer will destroy() cinfo on exit.  We don't want to set the
 | 
| -  // destroyer's object until cinfo is initialized.
 | 
| -  jpeg_create_decompress(&cinfo);
 | 
| -
 | 
| -  // set up the source manager
 | 
| -  jpeg_source_mgr srcmgr;
 | 
| -  srcmgr.init_source = InitSource;
 | 
| -  srcmgr.fill_input_buffer = FillInputBuffer;
 | 
| -  srcmgr.skip_input_data = SkipInputData;
 | 
| -  srcmgr.resync_to_restart = jpeg_resync_to_restart;  // use default routine
 | 
| -  srcmgr.term_source = TermSource;
 | 
| -  cinfo.src = &srcmgr;
 | 
| -
 | 
| -  JpegDecoderState state(input, input_size);
 | 
| -  cinfo.client_data = &state;
 | 
| -
 | 
| -  // fill the file metadata into our buffer
 | 
| -  if (jpeg_read_header(&cinfo, true) != JPEG_HEADER_OK)
 | 
| -    return false;
 | 
| -
 | 
| -  // we want to always get RGB data out
 | 
| -  switch (cinfo.jpeg_color_space) {
 | 
| -    case JCS_GRAYSCALE:
 | 
| -    case JCS_RGB:
 | 
| -    case JCS_YCbCr:
 | 
| -      cinfo.out_color_space = JCS_RGB;
 | 
| -      break;
 | 
| -    case JCS_CMYK:
 | 
| -    case JCS_YCCK:
 | 
| -    default:
 | 
| -      // Mozilla errors out on these color spaces, so I presume that the jpeg
 | 
| -      // library can't do automatic color space conversion for them. We don't
 | 
| -      // care about these anyway.
 | 
| -      return false;
 | 
| -  }
 | 
| -  cinfo.output_components = 3;
 | 
| -
 | 
| -  jpeg_calc_output_dimensions(&cinfo);
 | 
| -  *w = cinfo.output_width;
 | 
| -  *h = cinfo.output_height;
 | 
| -
 | 
| -  jpeg_start_decompress(&cinfo);
 | 
| -
 | 
| -  // FIXME(brettw) we may want to allow the capability for callers to request
 | 
| -  // how to align row lengths as we do for the compressor.
 | 
| -  int row_read_stride = cinfo.output_width * cinfo.output_components;
 | 
| -
 | 
| -  if (format == FORMAT_RGB) {
 | 
| -    // easy case, row needs no conversion
 | 
| -    int row_write_stride = row_read_stride;
 | 
| -    output->resize(row_write_stride * cinfo.output_height);
 | 
| -
 | 
| -    for (int row = 0; row < static_cast<int>(cinfo.output_height); row++) {
 | 
| -      unsigned char* rowptr = &(*output)[row * row_write_stride];
 | 
| -      if (!jpeg_read_scanlines(&cinfo, &rowptr, 1))
 | 
| -        return false;
 | 
| -    }
 | 
| -  } else {
 | 
| -    // Rows need conversion to output format: read into a temporary buffer and
 | 
| -    // expand to the final one. Performance: we could avoid the extra
 | 
| -    // allocation by doing the expansion in-place.
 | 
| -    int row_write_stride;
 | 
| -    void (*converter)(const unsigned char* rgb, int w, unsigned char* out);
 | 
| -    if (format == FORMAT_RGBA ||
 | 
| -        (format == FORMAT_SkBitmap && SK_R32_SHIFT == 0)) {
 | 
| -      row_write_stride = cinfo.output_width * 4;
 | 
| -      converter = AddAlpha;
 | 
| -    } else if (format == FORMAT_BGRA ||
 | 
| -               (format == FORMAT_SkBitmap && SK_B32_SHIFT == 0)) {
 | 
| -      row_write_stride = cinfo.output_width * 4;
 | 
| -      converter = RGBtoBGRA;
 | 
| -    } else {
 | 
| -      NOTREACHED() << "Invalid pixel format";
 | 
| -      jpeg_destroy_decompress(&cinfo);
 | 
| -      return false;
 | 
| -    }
 | 
| -
 | 
| -    output->resize(row_write_stride * cinfo.output_height);
 | 
| -
 | 
| -    scoped_array<unsigned char> row_data(new unsigned char[row_read_stride]);
 | 
| -    unsigned char* rowptr = row_data.get();
 | 
| -    for (int row = 0; row < static_cast<int>(cinfo.output_height); row++) {
 | 
| -      if (!jpeg_read_scanlines(&cinfo, &rowptr, 1))
 | 
| -        return false;
 | 
| -      converter(rowptr, *w, &(*output)[row * row_write_stride]);
 | 
| -    }
 | 
| -  }
 | 
| -
 | 
| -  jpeg_finish_decompress(&cinfo);
 | 
| -  jpeg_destroy_decompress(&cinfo);
 | 
| -  return true;
 | 
| -}
 | 
| -
 | 
| -// static
 | 
| -SkBitmap* JPEGCodec::Decode(const unsigned char* input, size_t input_size) {
 | 
| -  int w, h;
 | 
| -  std::vector<unsigned char> data_vector;
 | 
| -  if (!Decode(input, input_size, FORMAT_SkBitmap, &data_vector, &w, &h))
 | 
| -    return NULL;
 | 
| -
 | 
| -  // Skia only handles 32 bit images.
 | 
| -  int data_length = w * h * 4;
 | 
| -
 | 
| -  SkBitmap* bitmap = new SkBitmap();
 | 
| -  bitmap->setConfig(SkBitmap::kARGB_8888_Config, w, h);
 | 
| -  bitmap->allocPixels();
 | 
| -  memcpy(bitmap->getAddr32(0, 0), &data_vector[0], data_length);
 | 
| -
 | 
| -  return bitmap;
 | 
| -}
 | 
| -
 | 
| -}  // namespace gfx
 | 
| 
 |