components/favicon_base/favicon_util.cc

   1 // Copyright 2014 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 "components/favicon_base/favicon_util.h"
   6
   7 #include <cmath>
   8
   9 #include "components/favicon_base/favicon_types.h"
  10 #include "components/favicon_base/select_favicon_frames.h"
  11 #include "skia/ext/image_operations.h"
  12 #include "third_party/skia/include/core/SkBitmap.h"
  13 #include "third_party/skia/include/core/SkCanvas.h"
  14 #include "ui/base/layout.h"
  15 #include "ui/gfx/codec/png_codec.h"
  16 #include "ui/gfx/favicon_size.h"
  17 #include "ui/gfx/geometry/size.h"
  18 #include "ui/gfx/image/image_png_rep.h"
  19 #include "ui/gfx/image/image_skia.h"
  20
  21 #if defined(OS_MACOSX) && !defined(OS_IOS)
  22 #include "base/mac/mac_util.h"
  23 #endif  // defined(OS_MACOSX) && !defined(OS_IOS)
  24
  25 namespace favicon_base {
  26 namespace {
  27
  28 // Creates image reps of DIP size |favicon_size| for the subset of
  29 // |favicon_scales| for which the image reps can be created without resizing
  30 // or decoding the bitmap data.
  31 std::vector<gfx::ImagePNGRep> SelectFaviconFramesFromPNGsWithoutResizing(
  32     const std::vector<favicon_base::FaviconRawBitmapResult>& png_data,
  33     const std::vector<float>& favicon_scales,
  34     int favicon_size) {
  35   std::vector<gfx::ImagePNGRep> png_reps;
  36   if (png_data.empty())
  37     return png_reps;
  38
  39   // A |favicon_size| of 0 indicates that the largest frame is desired.
  40   if (favicon_size == 0) {
  41     int maximum_area = 0;
  42     scoped_refptr<base::RefCountedMemory> best_candidate;
  43     for (size_t i = 0; i < png_data.size(); ++i) {
  44       int area = png_data[i].pixel_size.GetArea();
  45       if (area > maximum_area) {
  46         maximum_area = area;
  47         best_candidate = png_data[i].bitmap_data;
  48       }
  49     }
  50     png_reps.push_back(gfx::ImagePNGRep(best_candidate, 1.0f));
  51     return png_reps;
  52   }
  53
  54   // Build a map which will be used to determine the scale used to
  55   // create a bitmap with given pixel size.
  56   std::map<int, float> desired_pixel_sizes;
  57   for (size_t i = 0; i < favicon_scales.size(); ++i) {
  58     int pixel_size =
  59         static_cast<int>(std::ceil(favicon_size * favicon_scales[i]));
  60     desired_pixel_sizes[pixel_size] = favicon_scales[i];
  61   }
  62
  63   for (size_t i = 0; i < png_data.size(); ++i) {
  64     if (!png_data[i].is_valid())
  65       continue;
  66
  67     const gfx::Size& pixel_size = png_data[i].pixel_size;
  68     if (pixel_size.width() != pixel_size.height())
  69       continue;
  70
  71     std::map<int, float>::iterator it =
  72         desired_pixel_sizes.find(pixel_size.width());
  73     if (it == desired_pixel_sizes.end())
  74       continue;
  75
  76     png_reps.push_back(gfx::ImagePNGRep(png_data[i].bitmap_data, it->second));
  77   }
  78
  79   return png_reps;
  80 }
  81
  82 // Returns a resampled bitmap of |desired_size| x |desired_size| by resampling
  83 // the best bitmap out of |input_bitmaps|.
  84 // ResizeBitmapByDownsamplingIfPossible() is similar to SelectFaviconFrames()
  85 // but it operates on bitmaps which have already been resampled via
  86 // SelectFaviconFrames().
  87 SkBitmap ResizeBitmapByDownsamplingIfPossible(
  88     const std::vector<SkBitmap>& input_bitmaps,
  89     int desired_size) {
  90   DCHECK(!input_bitmaps.empty());
  91   DCHECK_NE(0, desired_size);
  92
  93   SkBitmap best_bitmap;
  94   for (size_t i = 0; i < input_bitmaps.size(); ++i) {
  95     const SkBitmap& input_bitmap = input_bitmaps[i];
  96     if (input_bitmap.width() == desired_size &&
  97         input_bitmap.height() == desired_size) {
  98       return input_bitmap;
  99     } else if (best_bitmap.isNull()) {
 100       best_bitmap = input_bitmap;
 101     } else if (input_bitmap.width() >= best_bitmap.width() &&
 102                input_bitmap.height() >= best_bitmap.height()) {
 103       if (best_bitmap.width() < desired_size ||
 104           best_bitmap.height() < desired_size) {
 105         best_bitmap = input_bitmap;
 106       }
 107     } else {
 108       if (input_bitmap.width() >= desired_size &&
 109           input_bitmap.height() >= desired_size) {
 110         best_bitmap = input_bitmap;
 111       }
 112     }
 113   }
 114
 115   if (desired_size % best_bitmap.width() == 0 &&
 116       desired_size % best_bitmap.height() == 0) {
 117     // Use nearest neighbour resampling if upsampling by an integer. This
 118     // makes the result look similar to the result of SelectFaviconFrames().
 119     SkBitmap bitmap;
 120     bitmap.allocN32Pixels(desired_size, desired_size);
 121     if (!best_bitmap.isOpaque())
 122       bitmap.eraseARGB(0, 0, 0, 0);
 123
 124     SkCanvas canvas(bitmap);
 125     canvas.drawBitmapRect(
 126         best_bitmap, SkRect::MakeIWH(desired_size, desired_size), NULL);
 127     return bitmap;
 128   }
 129   return skia::ImageOperations::Resize(best_bitmap,
 130                                        skia::ImageOperations::RESIZE_LANCZOS3,
 131                                        desired_size,
 132                                        desired_size);
 133 }
 134
 135 }  // namespace
 136
 137 std::vector<float> GetFaviconScales() {
 138   const float kScale1x = 1.0f;
 139   std::vector<ui::ScaleFactor> resource_scale_factors =
 140       ui::GetSupportedScaleFactors();
 141
 142   // TODO(ios): 1.0f should not be necessary on iOS retina devices. However
 143   // the sync service only supports syncing 100p favicons. Until sync supports
 144   // other scales 100p is needed in the list of scales to retrieve and
 145   // store the favicons in both 100p for sync and 200p for display. cr/160503.
 146   std::vector<float> favicon_scales(1, kScale1x);
 147   for (size_t i = 0; i < resource_scale_factors.size(); ++i) {
 148     if (resource_scale_factors[i] != ui::SCALE_FACTOR_100P)
 149       favicon_scales.push_back(
 150           ui::GetScaleForScaleFactor(resource_scale_factors[i]));
 151   }
 152   return favicon_scales;
 153 }
 154
 155 void SetFaviconColorSpace(gfx::Image* image) {
 156 #if defined(OS_MACOSX) && !defined(OS_IOS)
 157   image->SetSourceColorSpace(base::mac::GetSystemColorSpace());
 158 #endif  // defined(OS_MACOSX) && !defined(OS_IOS)
 159 }
 160
 161 gfx::Image SelectFaviconFramesFromPNGs(
 162     const std::vector<favicon_base::FaviconRawBitmapResult>& png_data,
 163     const std::vector<float>& favicon_scales,
 164     int favicon_size) {
 165   // Create image reps for as many scales as possible without resizing
 166   // the bitmap data or decoding it. FaviconHandler stores already resized
 167   // favicons into history so no additional resizing should be needed in the
 168   // common case.
 169   // Creating the gfx::Image from |png_data| without resizing or decoding if
 170   // possible is important because:
 171   // - Sync does a byte-to-byte comparison of gfx::Image::As1xPNGBytes() to
 172   //   the data it put into the database in order to determine whether any
 173   //   updates should be pushed to sync.
 174   // - The decoding occurs on the UI thread and the decoding can be a
 175   //   significant performance hit if a user has many bookmarks.
 176   // TODO(pkotwicz): Move the decoding off the UI thread.
 177   std::vector<gfx::ImagePNGRep> png_reps =
 178       SelectFaviconFramesFromPNGsWithoutResizing(
 179           png_data, favicon_scales, favicon_size);
 180
 181   // SelectFaviconFramesFromPNGsWithoutResizing() should have selected the
 182   // largest favicon if |favicon_size| == 0.
 183   if (favicon_size == 0)
 184     return gfx::Image(png_reps);
 185
 186   std::vector<float> favicon_scales_to_generate = favicon_scales;
 187   for (size_t i = 0; i < png_reps.size(); ++i) {
 188     std::vector<float>::iterator iter = std::find(
 189         favicon_scales_to_generate.begin(),
 190         favicon_scales_to_generate.end(),
 191         png_reps[i].scale);
 192     if (iter != favicon_scales_to_generate.end())
 193       favicon_scales_to_generate.erase(iter);
 194   }
 195
 196   if (favicon_scales_to_generate.empty())
 197     return gfx::Image(png_reps);
 198
 199   std::vector<SkBitmap> bitmaps;
 200   for (size_t i = 0; i < png_data.size(); ++i) {
 201     if (!png_data[i].is_valid())
 202       continue;
 203
 204     SkBitmap bitmap;
 205     if (gfx::PNGCodec::Decode(png_data[i].bitmap_data->front(),
 206                               png_data[i].bitmap_data->size(),
 207                               &bitmap)) {
 208       bitmaps.push_back(bitmap);
 209     }
 210   }
 211
 212   if (bitmaps.empty())
 213     return gfx::Image();
 214
 215   gfx::ImageSkia resized_image_skia;
 216   for (size_t i = 0; i < favicon_scales_to_generate.size(); ++i) {
 217     float scale = favicon_scales_to_generate[i];
 218     int desired_size_in_pixel =
 219         static_cast<int>(std::ceil(favicon_size * scale));
 220     SkBitmap bitmap =
 221         ResizeBitmapByDownsamplingIfPossible(bitmaps, desired_size_in_pixel);
 222     resized_image_skia.AddRepresentation(gfx::ImageSkiaRep(bitmap, scale));
 223   }
 224
 225   if (png_reps.empty())
 226     return gfx::Image(resized_image_skia);
 227
 228   std::vector<gfx::ImageSkiaRep> resized_image_skia_reps =
 229       resized_image_skia.image_reps();
 230   for (size_t i = 0; i < resized_image_skia_reps.size(); ++i) {
 231     scoped_refptr<base::RefCountedBytes> png_bytes(new base::RefCountedBytes());
 232     if (gfx::PNGCodec::EncodeBGRASkBitmap(
 233             resized_image_skia_reps[i].sk_bitmap(),
 234             false,
 235             &png_bytes->data())) {
 236       png_reps.push_back(
 237           gfx::ImagePNGRep(png_bytes, resized_image_skia_reps[i].scale()));
 238     }
 239   }
 240
 241   return gfx::Image(png_reps);
 242 }
 243
 244 }  // namespace favicon_base