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/*
* Copyright (c) 2018 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 API_VIDEO_CODECS_VIDEO_CODEC_H_
#define API_VIDEO_CODECS_VIDEO_CODEC_H_
#include <stddef.h>
#include <stdint.h>
#include <string>
#include "absl/types/optional.h"
#include "api/video/video_codec_constants.h"
#include "api/video/video_codec_type.h"
#include "api/video_codecs/scalability_mode.h"
#include "api/video_codecs/simulcast_stream.h"
#include "api/video_codecs/spatial_layer.h"
#include "rtc_base/system/rtc_export.h"
namespace webrtc {
// The VideoCodec class represents an old defacto-apis, which we're migrating
// away from slowly.
// Video codec
enum class VideoCodecComplexity {
kComplexityLow = -1,
kComplexityNormal = 0,
kComplexityHigh = 1,
kComplexityHigher = 2,
kComplexityMax = 3
};
// VP8 specific
struct VideoCodecVP8 {
bool operator==(const VideoCodecVP8& other) const;
bool operator!=(const VideoCodecVP8& other) const {
return !(*this == other);
}
// Temporary utility method for transition deleting numberOfTemporalLayers
// setting (replaced by ScalabilityMode).
void SetNumberOfTemporalLayers(unsigned char n) {
numberOfTemporalLayers = n;
}
unsigned char numberOfTemporalLayers;
bool denoisingOn;
bool automaticResizeOn;
int keyFrameInterval;
};
enum class InterLayerPredMode : int {
kOff = 0, // Inter-layer prediction is disabled.
kOn = 1, // Inter-layer prediction is enabled.
kOnKeyPic = 2 // Inter-layer prediction is enabled but limited to key frames.
};
// VP9 specific.
struct VideoCodecVP9 {
bool operator==(const VideoCodecVP9& other) const;
bool operator!=(const VideoCodecVP9& other) const {
return !(*this == other);
}
// Temporary utility method for transition deleting numberOfTemporalLayers
// setting (replaced by ScalabilityMode).
void SetNumberOfTemporalLayers(unsigned char n) {
numberOfTemporalLayers = n;
}
unsigned char numberOfTemporalLayers;
bool denoisingOn;
int keyFrameInterval;
bool adaptiveQpMode;
bool automaticResizeOn;
unsigned char numberOfSpatialLayers;
bool flexibleMode;
InterLayerPredMode interLayerPred;
};
// H264 specific.
struct VideoCodecH264 {
bool operator==(const VideoCodecH264& other) const;
bool operator!=(const VideoCodecH264& other) const {
return !(*this == other);
}
// Temporary utility method for transition deleting numberOfTemporalLayers
// setting (replaced by ScalabilityMode).
void SetNumberOfTemporalLayers(unsigned char n) {
numberOfTemporalLayers = n;
}
int keyFrameInterval;
uint8_t numberOfTemporalLayers;
};
struct VideoCodecAV1 {
bool operator==(const VideoCodecAV1& other) const {
return automatic_resize_on == other.automatic_resize_on;
}
bool operator!=(const VideoCodecAV1& other) const {
return !(*this == other);
}
bool automatic_resize_on;
};
// Translates from name of codec to codec type and vice versa.
RTC_EXPORT const char* CodecTypeToPayloadString(VideoCodecType type);
RTC_EXPORT VideoCodecType PayloadStringToCodecType(const std::string& name);
union VideoCodecUnion {
VideoCodecVP8 VP8;
VideoCodecVP9 VP9;
VideoCodecH264 H264;
VideoCodecAV1 AV1;
};
enum class VideoCodecMode { kRealtimeVideo, kScreensharing };
// Common video codec properties
class RTC_EXPORT VideoCodec {
public:
VideoCodec();
// Scalability mode as described in
absl::optional<ScalabilityMode> GetScalabilityMode() const {
return scalability_mode_;
}
void SetScalabilityMode(ScalabilityMode scalability_mode) {
scalability_mode_ = scalability_mode;
}
void UnsetScalabilityMode() { scalability_mode_ = absl::nullopt; }
VideoCodecComplexity GetVideoEncoderComplexity() const;
void SetVideoEncoderComplexity(VideoCodecComplexity complexity_setting);
bool GetFrameDropEnabled() const;
void SetFrameDropEnabled(bool enabled);
bool IsSinglecast() const { return numberOfSimulcastStreams <= 1; }
bool IsSimulcast() const { return !IsSinglecast(); }
// Public variables. TODO(hta): Make them private with accessors.
VideoCodecType codecType;
// TODO(nisse): Change to int, for consistency.
uint16_t width;
uint16_t height;
unsigned int startBitrate; // kilobits/sec.
unsigned int maxBitrate; // kilobits/sec.
unsigned int minBitrate; // kilobits/sec.
uint32_t maxFramerate;
// This enables/disables encoding and sending when there aren't multiple
// simulcast streams,by allocating 0 bitrate if inactive.
bool active;
unsigned int qpMax;
// The actual number of simulcast streams. This is <= 1 in singlecast (it can
// be 0 in old code paths), but it is also 1 in the {active,inactive,inactive}
// "single RTP simulcast" use case and the legacy kSVC use case. In all other
// cases this is the same as the number of encodings (which may include
// inactive encodings). In other words:
// - `numberOfSimulcastStreams <= 1` in singlecast and singlecast-like setups
// including legacy kSVC (encodings interpreted as spatial layers) or
// standard kSVC (1 active encoding).
// - `numberOfSimulcastStreams > 1` in simulcast of 2+ active encodings.
unsigned char numberOfSimulcastStreams;
SimulcastStream simulcastStream[kMaxSimulcastStreams];
SpatialLayer spatialLayers[kMaxSpatialLayers];
VideoCodecMode mode;
bool expect_encode_from_texture;
// Timing frames configuration. There is delay of delay_ms between two
// consequent timing frames, excluding outliers. Frame is always made a
// timing frame if it's at least outlier_ratio in percent of "ideal" average
// frame given bitrate and framerate, i.e. if it's bigger than
// |outlier_ratio / 100.0 * bitrate_bps / fps| in bits. This way, timing
// frames will not be sent too often usually. Yet large frames will always
// have timing information for debug purposes because they are more likely to
// cause extra delays.
struct TimingFrameTriggerThresholds {
int64_t delay_ms;
uint16_t outlier_ratio_percent;
} timing_frame_thresholds;
// Legacy Google conference mode flag for simulcast screenshare
bool legacy_conference_mode;
bool operator==(const VideoCodec& other) const = delete;
bool operator!=(const VideoCodec& other) const = delete;
std::string ToString() const;
// Accessors for codec specific information.
// There is a const version of each that returns a reference,
// and a non-const version that returns a pointer, in order
// to allow modification of the parameters.
VideoCodecVP8* VP8();
const VideoCodecVP8& VP8() const;
VideoCodecVP9* VP9();
const VideoCodecVP9& VP9() const;
VideoCodecH264* H264();
const VideoCodecH264& H264() const;
VideoCodecAV1* AV1();
const VideoCodecAV1& AV1() const;
private:
// TODO(hta): Consider replacing the union with a pointer type.
// This will allow removing the VideoCodec* types from this file.
VideoCodecUnion codec_specific_;
absl::optional<ScalabilityMode> scalability_mode_;
// 'complexity_' indicates the CPU capability of the client. It's used to
// determine encoder CPU complexity (e.g., cpu_used for VP8, VP9. and AV1).
VideoCodecComplexity complexity_;
bool frame_drop_enabled_ = false;
};
} // namespace webrtc
#endif // API_VIDEO_CODECS_VIDEO_CODEC_H_