| // Copyright (c) 2012 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 "chrome/browser/history/select_favicon_frames.h" |
| |
| #include <set> |
| |
| #include "skia/ext/image_operations.h" |
| #include "third_party/skia/include/core/SkCanvas.h" |
| #include "ui/gfx/image/image.h" |
| #include "ui/gfx/image/image_skia.h" |
| #include "ui/gfx/size.h" |
| |
| namespace { |
| |
| // Return gfx::Size vector with the pixel sizes of |bitmaps|. |
| void SizesFromBitmaps(const std::vector<SkBitmap>& bitmaps, |
| std::vector<gfx::Size>* sizes) { |
| for (size_t i = 0; i < bitmaps.size(); ++i) |
| sizes->push_back(gfx::Size(bitmaps[i].width(), bitmaps[i].height())); |
| } |
| |
| size_t BiggestCandidate(const std::vector<gfx::Size>& candidate_sizes) { |
| size_t max_index = 0; |
| int max_area = candidate_sizes[0].GetArea(); |
| for (size_t i = 1; i < candidate_sizes.size(); ++i) { |
| int area = candidate_sizes[i].GetArea(); |
| if (area > max_area) { |
| max_area = area; |
| max_index = i; |
| } |
| } |
| return max_index; |
| } |
| |
| SkBitmap SampleNearestNeighbor(const SkBitmap& contents, int desired_size) { |
| SkBitmap bitmap; |
| bitmap.setConfig( |
| SkBitmap::kARGB_8888_Config, desired_size, desired_size); |
| bitmap.allocPixels(); |
| if (!contents.isOpaque()) |
| bitmap.eraseARGB(0, 0, 0, 0); |
| |
| { |
| SkCanvas canvas(bitmap); |
| SkRect dest(SkRect::MakeWH(desired_size, desired_size)); |
| canvas.drawBitmapRect(contents, NULL, dest); |
| } |
| |
| return bitmap; |
| } |
| |
| enum ResizeMethod { |
| NONE, |
| SAMPLE_NEAREST_NEIGHBOUR, |
| LANCZOS |
| }; |
| |
| size_t GetCandidateIndexWithBestScore( |
| const std::vector<gfx::Size>& candidate_sizes_in_pixel, |
| ui::ScaleFactor scale_factor, |
| int desired_size_in_dip, |
| float* score, |
| ResizeMethod* resize_method) { |
| DCHECK_NE(desired_size_in_dip, 0); |
| |
| float scale = ui::GetScaleFactorScale(scale_factor); |
| int desired_size_in_pixel = |
| static_cast<int>(desired_size_in_dip * scale + 0.5f); |
| |
| // Try to find an exact match. |
| for (size_t i = 0; i < candidate_sizes_in_pixel.size(); ++i) { |
| if (candidate_sizes_in_pixel[i].width() == desired_size_in_pixel && |
| candidate_sizes_in_pixel[i].height() == desired_size_in_pixel) { |
| *score = 1; |
| *resize_method = NONE; |
| return i; |
| } |
| } |
| |
| // Huge favicon bitmaps often have a completely different visual style from |
| // smaller favicon bitmaps. Avoid these favicon bitmaps when a favicon of |
| // gfx::kFaviconSize DIP is requested. |
| const int kHugeEdgeSizeInPixel = desired_size_in_pixel * 8; |
| |
| // Order of preference: |
| // 1) Bitmaps with width and height smaller than |kHugeEdgeSizeInPixel|. |
| // 2) Bitmaps which need to be scaled down instead of up. |
| // 3) Bitmaps which do not need to be scaled as much. |
| int candidate_index = -1; |
| float candidate_score = 0; |
| for (size_t i = 0; i < candidate_sizes_in_pixel.size(); ++i) { |
| float average_edge_in_pixel = (candidate_sizes_in_pixel[i].width() + |
| candidate_sizes_in_pixel[i].height()) / 2.0f; |
| |
| float score = 0; |
| if (candidate_sizes_in_pixel[i].width() >= kHugeEdgeSizeInPixel || |
| candidate_sizes_in_pixel[i].height() >= kHugeEdgeSizeInPixel) { |
| score = std::min(1.0f, desired_size_in_pixel / average_edge_in_pixel) * |
| 0.01f; |
| } else if (candidate_sizes_in_pixel[i].width() >= desired_size_in_pixel && |
| candidate_sizes_in_pixel[i].height() >= desired_size_in_pixel) { |
| score = desired_size_in_pixel / average_edge_in_pixel * 0.01f + 0.15f; |
| } else { |
| score = std::min(1.0f, average_edge_in_pixel / desired_size_in_pixel) * |
| 0.01f + 0.1f; |
| } |
| |
| if (candidate_index == -1 || score > candidate_score) { |
| candidate_index = i; |
| candidate_score = score; |
| } |
| } |
| *score = candidate_score; |
| |
| // Integer multiples are built using nearest neighbor sampling. Otherwise, |
| // Lanczos scaling is used. |
| const gfx::Size& candidate_size_in_pixel = |
| candidate_sizes_in_pixel[candidate_index]; |
| if (candidate_size_in_pixel.IsEmpty()) { |
| *resize_method = NONE; |
| } else if (desired_size_in_pixel % candidate_size_in_pixel.width() == 0 && |
| desired_size_in_pixel % candidate_size_in_pixel.height() == 0) { |
| *resize_method = SAMPLE_NEAREST_NEIGHBOUR; |
| } else { |
| *resize_method = LANCZOS; |
| } |
| return candidate_index; |
| } |
| |
| // Represents the index of the best candidate for a |scale_factor| from the |
| // |candidate_sizes| passed into GetCandidateIndicesWithBestScores(). |
| struct SelectionResult { |
| // index in |candidate_sizes| of the best candidate. |
| size_t index; |
| |
| // The ScaleFactor for which |index| is the best candidate. |
| ui::ScaleFactor scale_factor; |
| |
| // How the bitmap data that the bitmap with |candidate_sizes[index]| should |
| // be resized for displaying in the UI. |
| ResizeMethod resize_method; |
| }; |
| |
| void GetCandidateIndicesWithBestScores( |
| const std::vector<gfx::Size>& candidate_sizes, |
| const std::vector<ui::ScaleFactor>& scale_factors, |
| int desired_size, |
| float* match_score, |
| std::vector<SelectionResult>* results) { |
| if (candidate_sizes.empty()) { |
| *match_score = 0.0f; |
| return; |
| } |
| |
| if (desired_size == 0) { |
| // Just return the biggest image available. |
| SelectionResult result; |
| result.index = BiggestCandidate(candidate_sizes); |
| result.scale_factor = ui::SCALE_FACTOR_100P; |
| result.resize_method = NONE; |
| results->push_back(result); |
| if (match_score) |
| *match_score = 1.0f; |
| return; |
| } |
| |
| float total_score = 0; |
| for (size_t i = 0; i < scale_factors.size(); ++i) { |
| float score; |
| SelectionResult result; |
| result.scale_factor = scale_factors[i]; |
| result.index = GetCandidateIndexWithBestScore(candidate_sizes, |
| result.scale_factor, desired_size, &score, &result.resize_method); |
| results->push_back(result); |
| total_score += score; |
| } |
| |
| if (match_score) |
| *match_score = total_score / scale_factors.size(); |
| } |
| |
| // Resize |source_bitmap| using |resize_method|. |
| SkBitmap GetResizedBitmap(const SkBitmap& source_bitmap, |
| int desired_size_in_dip, |
| ui::ScaleFactor scale_factor, |
| ResizeMethod resize_method) { |
| float scale = ui::GetScaleFactorScale(scale_factor); |
| int desired_size_in_pixel = static_cast<int>( |
| desired_size_in_dip * scale + 0.5f); |
| |
| switch (resize_method) { |
| case NONE: |
| return source_bitmap; |
| case SAMPLE_NEAREST_NEIGHBOUR: |
| return SampleNearestNeighbor(source_bitmap, desired_size_in_pixel); |
| case LANCZOS: |
| return skia::ImageOperations::Resize( |
| source_bitmap, skia::ImageOperations::RESIZE_LANCZOS3, |
| desired_size_in_pixel, desired_size_in_pixel); |
| } |
| return source_bitmap; |
| } |
| |
| } // namespace |
| |
| const float kSelectFaviconFramesInvalidScore = -1.0f; |
| |
| gfx::ImageSkia SelectFaviconFrames( |
| const std::vector<SkBitmap>& bitmaps, |
| const std::vector<ui::ScaleFactor>& scale_factors, |
| int desired_size, |
| float* match_score) { |
| std::vector<gfx::Size> candidate_sizes; |
| SizesFromBitmaps(bitmaps, &candidate_sizes); |
| |
| std::vector<SelectionResult> results; |
| GetCandidateIndicesWithBestScores(candidate_sizes, scale_factors, |
| desired_size, match_score, &results); |
| |
| gfx::ImageSkia multi_image; |
| for (size_t i = 0; i < results.size(); ++i) { |
| const SelectionResult& result = results[i]; |
| SkBitmap resized_bitmap = GetResizedBitmap(bitmaps[result.index], |
| desired_size, result.scale_factor, result.resize_method); |
| multi_image.AddRepresentation( |
| gfx::ImageSkiaRep(resized_bitmap, result.scale_factor)); |
| } |
| return multi_image; |
| } |
| |
| void SelectFaviconFrameIndices( |
| const std::vector<gfx::Size>& frame_pixel_sizes, |
| const std::vector<ui::ScaleFactor>& scale_factors, |
| int desired_size, |
| std::vector<size_t>* best_indices, |
| float* match_score) { |
| std::vector<SelectionResult> results; |
| GetCandidateIndicesWithBestScores(frame_pixel_sizes, scale_factors, |
| desired_size, match_score, &results); |
| |
| std::set<size_t> already_added; |
| for (size_t i = 0; i < results.size(); ++i) { |
| size_t index = results[i].index; |
| // GetCandidateIndicesWithBestScores() will return duplicate indices if the |
| // bitmap data with |frame_pixel_sizes[index]| should be used for multiple |
| // scale factors. Remove duplicates here such that |best_indices| contains |
| // no duplicates. |
| if (already_added.find(index) == already_added.end()) { |
| already_added.insert(index); |
| best_indices->push_back(index); |
| } |
| } |
| } |