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// Copyright 2018 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 <vector>
#include "base/component_export.h"
#include "base/gtest_prod_util.h"
#include "base/macros.h"
#include "base/optional.h"
#include "services/media_session/public/cpp/media_metadata.h"
namespace gfx {
class Size;
} // namespace gfx
class GURL;
namespace media_session {
// MediaImageManager manages the MediaImage selection process.
// The scoring works as follows:
// - An image score is computed by multiplying the type score with the size
// score.
// - The type score is between 0 and 1 and is based on the image MIME type
// and/or file extension.
// - PNG and JPEG are prefered than others.
// - If unspecified, use the default type score (0.6).
// - The size score is between 0 and 1 and is computed by multiplying the
// dominant size score and aspect ratio score:
// - The dominant size score is between 0 and 1 and is computed using
// |min_size| and |ideal_size|.
// - If size < |min_size| (too small), the size score is 0.
// - If |min_size| <= size <= |ideal_size|, the score increases
// linearly from 0.2 to 1.
// - If size > |ideal_size|, the score is |ideal_size| / size which
// drops from 1 to 0.
// - When size is "any", the size score is 0.8.
// - If unspecified, use the default size score (0.4).
// - The aspect ratio score is between 0 and 1 and is computed by dividing
// the short edge length by the long edge.
// The |min_size| is the min size of the images to select in px. The
// |ideal_size| is the ideal size of the images to select in px.
MediaImageManager(int min_size, int ideal_size);
// Select the best image from the |images|. If an image could not be selected
// then will return null.
base::Optional<MediaMetadata::MediaImage> SelectImage(
const std::vector<MediaMetadata::MediaImage>& images);
FRIEND_TEST_ALL_PREFIXES(MediaImageManagerTest, CheckExpectedImageTypeHashes);
double GetImageScore(const MediaMetadata::MediaImage& image) const;
double GetImageSizeScore(const gfx::Size& size) const;
double GetImageDominantSizeScore(const gfx::Size& size) const;
static base::Optional<double> GetImageExtensionScore(const GURL& url);
static base::Optional<double> GetImageTypeScore(const base::string16& type);
const int min_size_;
const int ideal_size_;
} // namespace media_session