1 /*
2 * Copyright (c) 2020 The WebRTC project authors. All Rights Reserved.
3 *
4 * Use of this source code is governed by a BSD-style license
5 * that can be found in the LICENSE file in the root of the source
6 * tree. An additional intellectual property rights grant can be found
7 * in the file PATENTS. All contributing project authors may
8 * be found in the AUTHORS file in the root of the source tree.
9 */
10 #include "modules/video_coding/svc/scalability_structure_s2t1.h"
11
12 #include <utility>
13 #include <vector>
14
15 #include "absl/base/macros.h"
16 #include "api/transport/rtp/dependency_descriptor.h"
17 #include "rtc_base/checks.h"
18 #include "rtc_base/logging.h"
19
20 namespace webrtc {
21
22 constexpr int ScalabilityStructureS2T1::kNumSpatialLayers;
23
24 ScalabilityStructureS2T1::~ScalabilityStructureS2T1() = default;
25
26 ScalableVideoController::StreamLayersConfig
StreamConfig() const27 ScalabilityStructureS2T1::StreamConfig() const {
28 StreamLayersConfig result;
29 result.num_spatial_layers = kNumSpatialLayers;
30 result.num_temporal_layers = 1;
31 result.scaling_factor_num[0] = 1;
32 result.scaling_factor_den[0] = 2;
33 return result;
34 }
35
DependencyStructure() const36 FrameDependencyStructure ScalabilityStructureS2T1::DependencyStructure() const {
37 FrameDependencyStructure structure;
38 structure.num_decode_targets = kNumSpatialLayers;
39 structure.num_chains = kNumSpatialLayers;
40 structure.decode_target_protected_by_chain = {0, 1};
41 structure.templates.resize(4);
42 structure.templates[0].S(0).Dtis("S-").ChainDiffs({2, 1}).FrameDiffs({2});
43 structure.templates[1].S(0).Dtis("S-").ChainDiffs({0, 0});
44 structure.templates[2].S(1).Dtis("-S").ChainDiffs({1, 2}).FrameDiffs({2});
45 structure.templates[3].S(1).Dtis("-S").ChainDiffs({1, 0});
46 return structure;
47 }
48
49 std::vector<ScalableVideoController::LayerFrameConfig>
NextFrameConfig(bool restart)50 ScalabilityStructureS2T1::NextFrameConfig(bool restart) {
51 if (restart) {
52 can_reference_frame_for_spatial_id_.reset();
53 }
54 std::vector<LayerFrameConfig> configs;
55 configs.reserve(kNumSpatialLayers);
56 for (int sid = 0; sid < kNumSpatialLayers; ++sid) {
57 if (!active_decode_targets_[sid]) {
58 can_reference_frame_for_spatial_id_.reset(sid);
59 continue;
60 }
61 configs.emplace_back();
62 LayerFrameConfig& config = configs.back().S(sid);
63 if (can_reference_frame_for_spatial_id_[sid]) {
64 config.ReferenceAndUpdate(sid);
65 } else {
66 config.Keyframe().Update(sid);
67 can_reference_frame_for_spatial_id_.set(sid);
68 }
69 }
70
71 return configs;
72 }
73
OnEncodeDone(const LayerFrameConfig & config)74 GenericFrameInfo ScalabilityStructureS2T1::OnEncodeDone(
75 const LayerFrameConfig& config) {
76 GenericFrameInfo frame_info;
77 frame_info.spatial_id = config.SpatialId();
78 frame_info.temporal_id = config.TemporalId();
79 frame_info.encoder_buffers = config.Buffers();
80 frame_info.decode_target_indications = {
81 config.SpatialId() == 0 ? DecodeTargetIndication::kSwitch
82 : DecodeTargetIndication::kNotPresent,
83 config.SpatialId() == 1 ? DecodeTargetIndication::kSwitch
84 : DecodeTargetIndication::kNotPresent,
85 };
86 frame_info.part_of_chain = {config.SpatialId() == 0, config.SpatialId() == 1};
87 frame_info.active_decode_targets = active_decode_targets_;
88 return frame_info;
89 }
90
OnRatesUpdated(const VideoBitrateAllocation & bitrates)91 void ScalabilityStructureS2T1::OnRatesUpdated(
92 const VideoBitrateAllocation& bitrates) {
93 active_decode_targets_.set(0, bitrates.GetBitrate(/*sid=*/0, /*tid=*/0) > 0);
94 active_decode_targets_.set(1, bitrates.GetBitrate(/*sid=*/1, /*tid=*/0) > 0);
95 }
96
97 } // namespace webrtc
98