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/*
* Copyright (c) 2020 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_TRANSPORT_RTP_DEPENDENCY_DESCRIPTOR_H_
#define API_TRANSPORT_RTP_DEPENDENCY_DESCRIPTOR_H_
#include <stdint.h>
#include <initializer_list>
#include <memory>
#include <optional>
#include <vector>
#include "absl/container/inlined_vector.h"
#include "absl/strings/string_view.h"
#include "api/video/render_resolution.h"
namespace webrtc {
// Structures to build and parse dependency descriptor as described in
// Relationship of a frame to a Decode target.
enum class DecodeTargetIndication {
kNotPresent = 0, // DecodeTargetInfo symbol '-'
kDiscardable = 1, // DecodeTargetInfo symbol 'D'
kSwitch = 2, // DecodeTargetInfo symbol 'S'
kRequired = 3 // DecodeTargetInfo symbol 'R'
};
struct FrameDependencyTemplate {
// Setters are named briefly to chain them when building the template.
FrameDependencyTemplate& S(int spatial_layer);
FrameDependencyTemplate& T(int temporal_layer);
FrameDependencyTemplate& Dtis(absl::string_view dtis);
FrameDependencyTemplate& FrameDiffs(std::initializer_list<int> diffs);
FrameDependencyTemplate& ChainDiffs(std::initializer_list<int> diffs);
friend bool operator==(const FrameDependencyTemplate& lhs,
const FrameDependencyTemplate& rhs) {
return lhs.spatial_id == rhs.spatial_id &&
lhs.temporal_id == rhs.temporal_id &&
lhs.decode_target_indications == rhs.decode_target_indications &&
lhs.frame_diffs == rhs.frame_diffs &&
lhs.chain_diffs == rhs.chain_diffs;
}
int spatial_id = 0;
int temporal_id = 0;
absl::InlinedVector<DecodeTargetIndication, 10> decode_target_indications;
absl::InlinedVector<int, 4> frame_diffs;
absl::InlinedVector<int, 4> chain_diffs;
};
struct FrameDependencyStructure {
friend bool operator==(const FrameDependencyStructure& lhs,
const FrameDependencyStructure& rhs) {
return lhs.num_decode_targets == rhs.num_decode_targets &&
lhs.num_chains == rhs.num_chains &&
lhs.decode_target_protected_by_chain ==
rhs.decode_target_protected_by_chain &&
lhs.resolutions == rhs.resolutions && lhs.templates == rhs.templates;
}
int structure_id = 0;
int num_decode_targets = 0;
int num_chains = 0;
// If chains are used (num_chains > 0), maps decode target index into index of
// the chain protecting that target.
absl::InlinedVector<int, 10> decode_target_protected_by_chain;
absl::InlinedVector<RenderResolution, 4> resolutions;
std::vector<FrameDependencyTemplate> templates;
};
class DependencyDescriptorMandatory {
public:
void set_frame_number(int frame_number) { frame_number_ = frame_number; }
int frame_number() const { return frame_number_; }
void set_template_id(int template_id) { template_id_ = template_id; }
int template_id() const { return template_id_; }
void set_first_packet_in_frame(bool first) { first_packet_in_frame_ = first; }
bool first_packet_in_frame() const { return first_packet_in_frame_; }
void set_last_packet_in_frame(bool last) { last_packet_in_frame_ = last; }
bool last_packet_in_frame() const { return last_packet_in_frame_; }
private:
int frame_number_;
int template_id_;
bool first_packet_in_frame_;
bool last_packet_in_frame_;
};
struct DependencyDescriptor {
static constexpr int kMaxSpatialIds = 4;
static constexpr int kMaxTemporalIds = 8;
static constexpr int kMaxDecodeTargets = 32;
static constexpr int kMaxTemplates = 64;
bool first_packet_in_frame = true;
bool last_packet_in_frame = true;
int frame_number = 0;
FrameDependencyTemplate frame_dependencies;
std::optional<RenderResolution> resolution;
std::optional<uint32_t> active_decode_targets_bitmask;
std::unique_ptr<FrameDependencyStructure> attached_structure;
};
// Below are implementation details.
namespace webrtc_impl {
absl::InlinedVector<DecodeTargetIndication, 10> StringToDecodeTargetIndications(
absl::string_view indication_symbols);
} // namespace webrtc_impl
inline FrameDependencyTemplate& FrameDependencyTemplate::S(int spatial_layer) {
this->spatial_id = spatial_layer;
return *this;
}
inline FrameDependencyTemplate& FrameDependencyTemplate::T(int temporal_layer) {
this->temporal_id = temporal_layer;
return *this;
}
inline FrameDependencyTemplate& FrameDependencyTemplate::Dtis(
absl::string_view dtis) {
this->decode_target_indications =
webrtc_impl::StringToDecodeTargetIndications(dtis);
return *this;
}
inline FrameDependencyTemplate& FrameDependencyTemplate::FrameDiffs(
std::initializer_list<int> diffs) {
this->frame_diffs.assign(diffs.begin(), diffs.end());
return *this;
}
inline FrameDependencyTemplate& FrameDependencyTemplate::ChainDiffs(
std::initializer_list<int> diffs) {
this->chain_diffs.assign(diffs.begin(), diffs.end());
return *this;
}
} // namespace webrtc
#endif // API_TRANSPORT_RTP_DEPENDENCY_DESCRIPTOR_H_