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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_VIDEO_BITRATE_ALLOCATION_H_
#define API_VIDEO_VIDEO_BITRATE_ALLOCATION_H_
#include <stddef.h>
#include <stdint.h>
#include <limits>
#include <string>
#include <vector>
#include "absl/types/optional.h"
#include "api/video/video_codec_constants.h"
#include "rtc_base/system/rtc_export.h"
namespace webrtc {
// Class that describes how video bitrate, in bps, is allocated across temporal
// and spatial layers. Not that bitrates are NOT cumulative. Depending on if
// layers are dependent or not, it is up to the user to aggregate.
// For each index, the bitrate can also both set and unset. This is used with a
// set bps = 0 to signal an explicit "turn off" signal.
class RTC_EXPORT VideoBitrateAllocation {
public:
static constexpr uint32_t kMaxBitrateBps =
std::numeric_limits<uint32_t>::max();
VideoBitrateAllocation();
bool SetBitrate(size_t spatial_index,
size_t temporal_index,
uint32_t bitrate_bps);
bool HasBitrate(size_t spatial_index, size_t temporal_index) const;
uint32_t GetBitrate(size_t spatial_index, size_t temporal_index) const;
// Whether the specific spatial layers has the bitrate set in any of its
// temporal layers.
bool IsSpatialLayerUsed(size_t spatial_index) const;
// Get the sum of all the temporal layer for a specific spatial layer.
uint32_t GetSpatialLayerSum(size_t spatial_index) const;
// Sum of bitrates of temporal layers, from layer 0 to `temporal_index`
// inclusive, of specified spatial layer `spatial_index`. Bitrates of lower
// spatial layers are not included.
uint32_t GetTemporalLayerSum(size_t spatial_index,
size_t temporal_index) const;
// Returns a vector of the temporal layer bitrates for the specific spatial
// layer. Length of the returned vector is cropped to the highest temporal
// layer with a defined bitrate.
std::vector<uint32_t> GetTemporalLayerAllocation(size_t spatial_index) const;
// Returns one VideoBitrateAllocation for each spatial layer. This is used to
// configure simulcast streams. Note that the length of the returned vector is
// always kMaxSpatialLayers, the optional is unset for unused layers.
std::vector<absl::optional<VideoBitrateAllocation>> GetSimulcastAllocations()
const;
uint32_t get_sum_bps() const { return sum_; } // Sum of all bitrates.
uint32_t get_sum_kbps() const {
// Round down to not exceed the allocated bitrate.
return sum_ / 1000;
}
bool operator==(const VideoBitrateAllocation& other) const;
inline bool operator!=(const VideoBitrateAllocation& other) const {
return !(*this == other);
}
std::string ToString() const;
// Indicates if the allocation has some layers/streams disabled due to
// low available bandwidth.
void set_bw_limited(bool limited) { is_bw_limited_ = limited; }
bool is_bw_limited() const { return is_bw_limited_; }
private:
uint32_t sum_;
absl::optional<uint32_t> bitrates_[kMaxSpatialLayers][kMaxTemporalStreams];
bool is_bw_limited_;
};
} // namespace webrtc
#endif // API_VIDEO_VIDEO_BITRATE_ALLOCATION_H_