chromecast/public/media/media_pipeline_device_params.h

// Copyright 2014 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.

#ifndef CHROMECAST_PUBLIC_MEDIA_MEDIA_PIPELINE_DEVICE_PARAMS_H_
#define CHROMECAST_PUBLIC_MEDIA_MEDIA_PIPELINE_DEVICE_PARAMS_H_

#include <stdint.h>

#include <ostream>
#include <string>

namespace service_manager {
class Connector;
}  // namespace service_manager

namespace chromecast {
class TaskRunner;

namespace media {

enum class AudioContentType;  // See chromecast/public/volume_control.h

enum class AudioChannel {
  kAll = 0,
  kLeft = 1,
  kRight = 2,
};

// Supplies creation parameters to platform-specific pipeline backend.
struct MediaPipelineDeviceParams {
  enum MediaSyncType {
    // Default operation, synchronize playback using PTS with higher latency.
    kModeSyncPts = 0,
    // With this mode, synchronization is disabled and audio/video frames are
    // rendered "right away":
    // - for audio, frames are still rendered based on the sampling frequency
    // - for video, frames are rendered as soon as available at the output of
    //   the video decoder.
    //   The assumption is that no B frames are used when synchronization is
    //   disabled, otherwise B frames would always be skipped.
    kModeIgnorePts = 1,
    // In addition to the constraints above, also do not wait for vsync.
    kModeIgnorePtsAndVSync = 2,
  };

  enum AudioStreamType {
    // "Real" audio stream. If this stream underruns, all audio output may pause
    // until more real stream data is available.
    kAudioStreamNormal = 0,
    // Sound-effects audio stream. May be interrupted if a real audio stream
    // is created with a different sample rate. Underruns on an effects stream
    // do not affect output of real audio streams.
    kAudioStreamSoundEffects = 1,
  };

  MediaPipelineDeviceParams(TaskRunner* task_runner_in,
                            AudioContentType content_type_in,
                            const std::string& device_id_in);

  MediaPipelineDeviceParams(MediaSyncType sync_type_in,
                            TaskRunner* task_runner_in,
                            AudioContentType content_type_in,
                            const std::string& device_id_in);

  MediaPipelineDeviceParams(MediaSyncType sync_type_in,
                            AudioStreamType audio_type_in,
                            TaskRunner* task_runner_in,
                            AudioContentType content_type_in,
                            const std::string& device_id_in);

  MediaPipelineDeviceParams(const MediaPipelineDeviceParams& other);
  MediaPipelineDeviceParams(MediaPipelineDeviceParams&& other);

  MediaSyncType sync_type;
  const AudioStreamType audio_type;

  // task_runner allows backend implementations to post tasks to the media
  // thread.  Since all calls from cast_shell into the backend are made on
  // the media thread, this may simplify thread management and safety for
  // some backends.
  TaskRunner* const task_runner;

  // connector allows the backend to bind to services through ServiceManager.
  service_manager::Connector* connector;

  // Identifies the content type for volume control.
  const AudioContentType content_type;
  const std::string device_id;

  // ID of the current session.
  std::string session_id;

  // True if casting to multiple devices, or false otherwise.
  bool multiroom;

  // Audio channel this device is playing.
  AudioChannel audio_channel;

  // Intrinsic output delay of this device.
  int64_t output_delay_us;
};

inline MediaPipelineDeviceParams::MediaPipelineDeviceParams(
    TaskRunner* task_runner_in,
    AudioContentType content_type_in,
    const std::string& device_id_in)
    : MediaPipelineDeviceParams(kModeSyncPts,
                                kAudioStreamNormal,
                                task_runner_in,
                                content_type_in,
                                device_id_in) {}

inline MediaPipelineDeviceParams::MediaPipelineDeviceParams(
    MediaSyncType sync_type_in,
    TaskRunner* task_runner_in,
    AudioContentType content_type_in,
    const std::string& device_id_in)
    : MediaPipelineDeviceParams(sync_type_in,
                                kAudioStreamNormal,
                                task_runner_in,
                                content_type_in,
                                device_id_in) {}

inline MediaPipelineDeviceParams::MediaPipelineDeviceParams(
    MediaSyncType sync_type_in,
    AudioStreamType audio_type_in,
    TaskRunner* task_runner_in,
    AudioContentType content_type_in,
    const std::string& device_id_in)
    : sync_type(sync_type_in),
      audio_type(audio_type_in),
      task_runner(task_runner_in),
      connector(nullptr),
      content_type(content_type_in),
      device_id(device_id_in),
      multiroom(false),
      audio_channel(AudioChannel::kAll),
      output_delay_us(0) {}

inline MediaPipelineDeviceParams::MediaPipelineDeviceParams(
    const MediaPipelineDeviceParams& other) = default;

inline MediaPipelineDeviceParams::MediaPipelineDeviceParams(
    MediaPipelineDeviceParams&& other) = default;

inline std::ostream& operator<<(std::ostream& os, AudioChannel audio_channel) {
  switch (audio_channel) {
    case AudioChannel::kAll:
      os << "all";
      return os;
    case AudioChannel::kLeft:
      os << "left";
      return os;
    case AudioChannel::kRight:
      os << "right";
      return os;
  }
  os << "unknown";
  return os;
}

}  // namespace media
}  // namespace chromecast

#endif  // CHROMECAST_MEDIA_CMA_BACKEND_MEDIA_PIPELINE_DEVICE_PARAMS_H_