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#ifndef COMPONENTS_FAVICON_BASE_SELECT_FAVICON_FRAMES_H_ 6#define COMPONENTS_FAVICON_BASE_SELECT_FAVICON_FRAMES_H_ 7 8#include <vector> 9 10#include "base/basictypes.h" 11 12class SkBitmap; 13 14namespace gfx { 15class ImageSkia; 16class Size; 17} 18 19// Score which is smaller than the minimum score returned by 20// SelectFaviconFrames() or SelectFaviconFrameIndices(). 21extern const float kSelectFaviconFramesInvalidScore; 22 23// Takes a list of all bitmaps found in a .ico file, and creates an 24// ImageSkia that's |desired_size_in_dip| x |desired_size_in_dip| big. 25// Bitmaps are selected by using |SelectFaviconFrameIndices| and the 26// platform's supported favicon scales (favicon_base::GetFaviconScales()). 27// If |desired_size_in_dip| is 0, the largest bitmap is returned unmodified. 28// |original_sizes| are the original sizes of the bitmaps. (For instance, 29// WebContents::DownloadImage() does resampling if it is passed a max size.) 30// If score is non-NULL, it receives a score between 0 (bad) and 1 (good) 31// that describes how well |bitmaps| were able to produce an image at 32// |desired_size_in_dip| for |favicon_scales|. 33// The score is arbitrary, but it's best for exact size matches, 34// and gets worse the more resampling needs to happen. 35// If the resampling algorithm is modified, the resampling done in 36// FaviconUtil::SelectFaviconFramesFromPNGs() should probably be modified too as 37// it inspired by this method. 38// If an unsupported scale (not in the favicon_base::GetFaviconScales()) 39// is requested, the ImageSkia will automatically scales using lancoz3. 40gfx::ImageSkia CreateFaviconImageSkia( 41 const std::vector<SkBitmap>& bitmaps, 42 const std::vector<gfx::Size>& original_sizes, 43 int desired_size_in_dip, 44 float* score); 45 46// Takes a list of the pixel sizes of a favicon's favicon bitmaps and returns 47// the indices of the best sizes to use to create an ImageSkia with 48// ImageSkiaReps with edge sizes |desired_sizes|. If '0' is one of 49// |desired_sizes|, the index of the largest size is returned. If |score| is 50// non-NULL, |score| is set to a value between 0 (bad) and 1 (good) that 51// describes how well the bitmap data with the sizes at |best_indices| will 52// produce the ImageSkia. The score is arbitrary, but it's best for exact 53// matches, and gets worse the more resampling needs to happen. 54// TODO(pkotwicz): Change API so that |desired_sizes| being empty indicates 55// that the index of the largest size is requested. 56// TODO(pkotwicz): Remove callers of this method for which |frame_pixel_sizes| 57// are the sizes of the favicon bitmaps after they were resized. 58void SelectFaviconFrameIndices(const std::vector<gfx::Size>& frame_pixel_sizes, 59 const std::vector<int>& desired_sizes, 60 std::vector<size_t>* best_indices, 61 float* score); 62 63#endif // COMPONENTS_FAVICON_BASE_SELECT_FAVICON_FRAMES_H_ 64