cc/test/pixel_test_utils.cc

   1 // Copyright (c) 2012 The Chromium Authors. All rights reserved.
   2 // Use of this source code is governed by a BSD-style license that can be
   3 // found in the LICENSE file.
   4
   5 #include "cc/test/pixel_test_utils.h"
   6
   7 #include <string>
   8 #include <vector>
   9
  10 #include "base/base64.h"
  11 #include "base/files/file_util.h"
  12 #include "base/logging.h"
  13 #include "third_party/skia/include/core/SkBitmap.h"
  14 #include "ui/gfx/codec/png_codec.h"
  15
  16 namespace cc {
  17
  18 bool WritePNGFile(const SkBitmap& bitmap, const base::FilePath& file_path,
  19     bool discard_transparency) {
  20   std::vector<unsigned char> png_data;
  21   if (gfx::PNGCodec::EncodeBGRASkBitmap(bitmap,
  22                                         discard_transparency,
  23                                         &png_data) &&
  24       base::CreateDirectory(file_path.DirName())) {
  25     char* data = reinterpret_cast<char*>(&png_data[0]);
  26     int size = static_cast<int>(png_data.size());
  27     return base::WriteFile(file_path, data, size) == size;
  28   }
  29   return false;
  30 }
  31
  32 std::string GetPNGDataUrl(const SkBitmap& bitmap) {
  33   std::vector<unsigned char> png_data;
  34   gfx::PNGCodec::EncodeBGRASkBitmap(bitmap, false, &png_data);
  35   std::string data_url;
  36   data_url.insert(data_url.end(), png_data.begin(), png_data.end());
  37   base::Base64Encode(data_url, &data_url);
  38   data_url.insert(0, "data:image/png;base64,");
  39
  40   return data_url;
  41 }
  42
  43 bool ReadPNGFile(const base::FilePath& file_path, SkBitmap* bitmap) {
  44   DCHECK(bitmap);
  45   std::string png_data;
  46   return base::ReadFileToString(file_path, &png_data) &&
  47          gfx::PNGCodec::Decode(reinterpret_cast<unsigned char*>(&png_data[0]),
  48                                png_data.length(),
  49                                bitmap);
  50 }
  51
  52 bool MatchesPNGFile(const SkBitmap& gen_bmp, base::FilePath ref_img_path,
  53                     const PixelComparator& comparator) {
  54   SkBitmap ref_bmp;
  55   if (!ReadPNGFile(ref_img_path, &ref_bmp)) {
  56     LOG(ERROR) << "Cannot read reference image: " << ref_img_path.value();
  57     return false;
  58   }
  59
  60   // Check if images size matches
  61   if (gen_bmp.width() != ref_bmp.width() ||
  62       gen_bmp.height() != ref_bmp.height()) {
  63     LOG(ERROR)
  64         << "Dimensions do not match! "
  65         << "Actual: " << gen_bmp.width() << "x" << gen_bmp.height()
  66         << "; "
  67         << "Expected: " << ref_bmp.width() << "x" << ref_bmp.height();
  68     return false;
  69   }
  70
  71   // Shortcut for empty images. They are always equal.
  72   if (gen_bmp.width() == 0 || gen_bmp.height() == 0)
  73     return true;
  74
  75   bool compare = comparator.Compare(gen_bmp, ref_bmp);
  76   if (!compare) {
  77     std::string gen_bmp_data_url = GetPNGDataUrl(gen_bmp);
  78     std::string ref_bmp_data_url = GetPNGDataUrl(ref_bmp);
  79     LOG(ERROR) << "Pixels do not match!";
  80     LOG(ERROR) << "Actual: " << gen_bmp_data_url;
  81     LOG(ERROR) << "Expected: " << ref_bmp_data_url;
  82   }
  83   return compare;
  84 }
  85
  86 }  // namespace cc