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