chromium/cc/metrics/video_playback_roughness_reporter.h

// Copyright 2020 The Chromium Authors
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.

#ifndef CC_METRICS_VIDEO_PLAYBACK_ROUGHNESS_REPORTER_H_
#define CC_METRICS_VIDEO_PLAYBACK_ROUGHNESS_REPORTER_H_

#include <optional>

#include "base/containers/circular_deque.h"
#include "base/containers/flat_set.h"
#include "base/functional/callback.h"
#include "base/time/time.h"
#include "cc/cc_export.h"
#include "media/base/video_frame.h"
#include "media/base/video_types.h"
#include "ui/gfx/geometry/size.h"

namespace cc {

// This class tracks moments when each frame was submitted
// and when it was displayed. Then series of frames split into groups
// of consecutive frames, where each group takes about one second of playback.
// Such groups also called 'frame windows'. Each windows is assigned a roughness
// score that measures how far playback smoothness was from the ideal playback.
//
// Information about several windows and their roughness score is aggregated
// for a couple of playback minutes ("measurement interval") and then a window
// with 95-percentile-max-roughness is reported via the provided callback.
//
// This sufficiently bad roughness window is deemed to represent overall
// playback quality.
class CC_EXPORT VideoPlaybackRoughnessReporter { … };

}  // namespace cc

#endif  // CC_METRICS_VIDEO_PLAYBACK_ROUGHNESS_REPORTER_H_