video/render/video_render_frames.h

/*
 *  Copyright (c) 2012 The WebRTC project authors. All Rights Reserved.
 *
 *  Use of this source code is governed by a BSD-style license
 *  that can be found in the LICENSE file in the root of the source
 *  tree. An additional intellectual property rights grant can be found
 *  in the file PATENTS.  All contributing project authors may
 *  be found in the AUTHORS file in the root of the source tree.
 */

#ifndef VIDEO_RENDER_VIDEO_RENDER_FRAMES_H_
#define VIDEO_RENDER_VIDEO_RENDER_FRAMES_H_

#include <stddef.h>
#include <stdint.h>

#include <list>
#include <optional>

#include "api/environment/environment.h"
#include "api/video/video_frame.h"

namespace webrtc {

// Class definitions
class VideoRenderFrames {
 public:
  VideoRenderFrames(const Environment& env, uint32_t render_delay_ms);
  VideoRenderFrames(const VideoRenderFrames&) = delete;
  ~VideoRenderFrames();

  // Add a frame to the render queue
  int32_t AddFrame(VideoFrame&& new_frame);

  // Get a frame for rendering, or false if it's not time to render.
  std::optional<VideoFrame> FrameToRender();

  // Returns the number of ms to next frame to render
  uint32_t TimeToNextFrameRelease();

  bool HasPendingFrames() const;

 private:
  const Environment env_;

  // Sorted list with framed to be rendered, oldest first.
  std::list<VideoFrame> incoming_frames_;

  // Estimated delay from a frame is released until it's rendered.
  const uint32_t render_delay_ms_;

  int64_t last_render_time_ms_ = 0;
  size_t frames_dropped_ = 0;
};

}  // namespace webrtc

#endif  // VIDEO_RENDER_VIDEO_RENDER_FRAMES_H_