Move ui/gfx/codec/ into its own component.

ui/gfx/chromeos/codec/jpeg_codec_robust_slow.cc

-// Copyright 2015 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 "ui/gfx/chromeos/codec/jpeg_codec_robust_slow.h"
-
-#include <setjmp.h>
-
-#include <memory>
-
-#include "base/logging.h"
-#include "third_party/skia/include/core/SkBitmap.h"
-#include "third_party/skia/include/core/SkColorPriv.h"
-
-extern "C" {
-// IJG provides robust JPEG decode
-#include "third_party/libjpeg/jpeglib.h"
-}
-
-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;
-};
-
-void ErrorExit(jpeg_common_struct* cinfo) {
-  CoderErrorMgr *err = reinterpret_cast<CoderErrorMgr*>(cinfo->err);
-
-  // Return control to the setjmp point.
-  longjmp(err->setjmp_buffer, false);
-}
-
-}  // namespace
-
-// Decoder --------------------------------------------------------------------
-
-namespace {
-
-struct JpegDecoderState {
-  JpegDecoderState(const unsigned char* in, size_t len)
-      : input_buffer(in), input_buffer_length(len) {
-  }
-
-  const unsigned char* input_buffer;
-  size_t input_buffer_length;
-};
-
-// Callback to initialize the source.
-//
-// From the JPEG library:
-//  "Initialize source. This is called by jpeg_read_header() before any data is
-//   actually read. May leave bytes_in_buffer set to 0 (in which case a
-//   fill_input_buffer() call will occur immediately)."
-void InitSource(j_decompress_ptr cinfo) {
-  JpegDecoderState* state = static_cast<JpegDecoderState*>(cinfo->client_data);
-  cinfo->src->next_input_byte = state->input_buffer;
-  cinfo->src->bytes_in_buffer = state->input_buffer_length;
-}
-
-// Callback to fill the buffer. Since our buffer already contains all the data,
-// we should never need to provide more data. If libjpeg thinks it needs more
-// data, our input is probably corrupt.
-//
-// From the JPEG library:
-//  "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
-//   (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) {
-  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
-// should be able to do the skip itself (it has all the data).
-//
-// From the JPEG library:
-//  "Skip num_bytes worth of data. The buffer pointer and count should be
-//   advanced over num_bytes input bytes, refilling the buffer as needed. This
-//   is used to skip over a potentially large amount of uninteresting data
-//   (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
-//   should be treated as a no-op."
-void SkipInputData(j_decompress_ptr cinfo, long num_bytes) {
-  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;
-    cinfo->src->bytes_in_buffer = 0;
-  } else if (num_bytes > 0) {
-    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) {
-}
-
-#if !defined(JCS_EXTENSIONS)
-// 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++) {
-    memcpy(&rgba[x * 4], &rgb[x * 3], 3);
-    rgba[x * 4 + 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;
-  }
-}
-#endif  // !defined(JCS_EXTENSIONS)
-
-// 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 JPEGCodecRobustSlow::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:
-#ifdef JCS_EXTENSIONS
-      // Choose an output colorspace and return if it is an unsupported one.
-      // Same as JPEGCodec::Encode(), libjpeg-turbo supports all input formats
-      // used by Chromium (i.e. RGB, RGBA, and BGRA) and we just map the input
-      // parameters to a colorspace.
-      if (format == FORMAT_RGB) {
-        cinfo.out_color_space = JCS_RGB;
-        cinfo.output_components = 3;
-      } else if (format == FORMAT_RGBA ||
-                 (format == FORMAT_SkBitmap && SK_R32_SHIFT == 0)) {
-        cinfo.out_color_space = JCS_EXT_RGBX;
-        cinfo.output_components = 4;
-      } else if (format == FORMAT_BGRA ||
-                 (format == FORMAT_SkBitmap && SK_B32_SHIFT == 0)) {
-        cinfo.out_color_space = JCS_EXT_BGRX;
-        cinfo.output_components = 4;
-      } else {
-        // We can exit this function without calling jpeg_destroy_decompress()
-        // because DecompressDestroyer automaticaly calls it.
-        NOTREACHED() << "Invalid pixel format";
-        return false;
-      }
-#else
-      cinfo.out_color_space = JCS_RGB;
-#endif
-      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;
-  }
-#ifndef JCS_EXTENSIONS
-  cinfo.output_components = 3;
-#endif
-
-  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;
-
-#ifdef JCS_EXTENSIONS
-  // Create memory for a decoded image and write decoded lines to the memory
-  // without conversions same as JPEGCodec::Encode().
-  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
-  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);
-
-    std::unique_ptr<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]);
-    }
-  }
-#endif
-
-  jpeg_finish_decompress(&cinfo);
-  jpeg_destroy_decompress(&cinfo);
-  return true;
-}
-
-// static
-SkBitmap* JPEGCodecRobustSlow::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->allocN32Pixels(w, h);
-  memcpy(bitmap->getAddr32(0, 0), &data_vector[0], data_length);
-
-  return bitmap;
-}
-
-}  // namespace gfx