1 files changed, 138 insertions, 0 deletions
diff --git a/third_party/libwebrtc/modules/video_coding/svc/scalability_structure_key_svc.h b/third_party/libwebrtc/modules/video_coding/svc/scalability_structure_key_svc.h
new file mode 100644
index 0000000000..54760da431
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+++ b/third_party/libwebrtc/modules/video_coding/svc/scalability_structure_key_svc.h
@@ -0,0 +1,138 @@
+/*
+ *  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 MODULES_VIDEO_CODING_SVC_SCALABILITY_STRUCTURE_KEY_SVC_H_
+#define MODULES_VIDEO_CODING_SVC_SCALABILITY_STRUCTURE_KEY_SVC_H_
+
+#include <bitset>
+#include <vector>
+
+#include "api/transport/rtp/dependency_descriptor.h"
+#include "api/video/video_bitrate_allocation.h"
+#include "common_video/generic_frame_descriptor/generic_frame_info.h"
+#include "modules/video_coding/svc/scalable_video_controller.h"
+
+namespace webrtc {
+
+class ScalabilityStructureKeySvc : public ScalableVideoController {
+ public:
+  ScalabilityStructureKeySvc(int num_spatial_layers, int num_temporal_layers);
+  ~ScalabilityStructureKeySvc() override;
+
+  StreamLayersConfig StreamConfig() const override;
+
+  std::vector<LayerFrameConfig> NextFrameConfig(bool restart) override;
+  GenericFrameInfo OnEncodeDone(const LayerFrameConfig& config) override;
+  void OnRatesUpdated(const VideoBitrateAllocation& bitrates) override;
+
+ private:
+  enum FramePattern : int {
+    kNone,
+    kKey,
+    kDeltaT0,
+    kDeltaT2A,
+    kDeltaT1,
+    kDeltaT2B,
+  };
+  static constexpr int kMaxNumSpatialLayers = 3;
+  static constexpr int kMaxNumTemporalLayers = 3;
+
+  // Index of the buffer to store last frame for layer (`sid`, `tid`)
+  int BufferIndex(int sid, int tid) const {
+    return tid * num_spatial_layers_ + sid;
+  }
+  bool DecodeTargetIsActive(int sid, int tid) const {
+    return active_decode_targets_[sid * num_temporal_layers_ + tid];
+  }
+  void SetDecodeTargetIsActive(int sid, int tid, bool value) {
+    active_decode_targets_.set(sid * num_temporal_layers_ + tid, value);
+  }
+  bool TemporalLayerIsActive(int tid) const;
+  static DecodeTargetIndication Dti(int sid,
+                                    int tid,
+                                    const LayerFrameConfig& config);
+
+  std::vector<LayerFrameConfig> KeyframeConfig();
+  std::vector<LayerFrameConfig> T0Config();
+  std::vector<LayerFrameConfig> T1Config();
+  std::vector<LayerFrameConfig> T2Config(FramePattern pattern);
+
+  FramePattern NextPattern(FramePattern last_pattern) const;
+
+  const int num_spatial_layers_;
+  const int num_temporal_layers_;
+
+  FramePattern last_pattern_ = kNone;
+  std::bitset<kMaxNumSpatialLayers> spatial_id_is_enabled_;
+  std::bitset<kMaxNumSpatialLayers> can_reference_t1_frame_for_spatial_id_;
+  std::bitset<32> active_decode_targets_;
+};
+
+// S1  0--0--0-
+//     |       ...
+// S0  0--0--0-
+class ScalabilityStructureL2T1Key : public ScalabilityStructureKeySvc {
+ public:
+  ScalabilityStructureL2T1Key() : ScalabilityStructureKeySvc(2, 1) {}
+  ~ScalabilityStructureL2T1Key() override;
+
+  FrameDependencyStructure DependencyStructure() const override;
+};
+
+// S1T1     0   0
+//         /   /   /
+// S1T0   0---0---0
+//        |         ...
+// S0T1   | 0   0
+//        |/   /   /
+// S0T0   0---0---0
+// Time-> 0 1 2 3 4
+class ScalabilityStructureL2T2Key : public ScalabilityStructureKeySvc {
+ public:
+  ScalabilityStructureL2T2Key() : ScalabilityStructureKeySvc(2, 2) {}
+  ~ScalabilityStructureL2T2Key() override;
+
+  FrameDependencyStructure DependencyStructure() const override;
+};
+
+class ScalabilityStructureL2T3Key : public ScalabilityStructureKeySvc {
+ public:
+  ScalabilityStructureL2T3Key() : ScalabilityStructureKeySvc(2, 3) {}
+  ~ScalabilityStructureL2T3Key() override;
+
+  FrameDependencyStructure DependencyStructure() const override;
+};
+
+class ScalabilityStructureL3T1Key : public ScalabilityStructureKeySvc {
+ public:
+  ScalabilityStructureL3T1Key() : ScalabilityStructureKeySvc(3, 1) {}
+  ~ScalabilityStructureL3T1Key() override;
+
+  FrameDependencyStructure DependencyStructure() const override;
+};
+
+class ScalabilityStructureL3T2Key : public ScalabilityStructureKeySvc {
+ public:
+  ScalabilityStructureL3T2Key() : ScalabilityStructureKeySvc(3, 2) {}
+  ~ScalabilityStructureL3T2Key() override;
+
+  FrameDependencyStructure DependencyStructure() const override;
+};
+
+class ScalabilityStructureL3T3Key : public ScalabilityStructureKeySvc {
+ public:
+  ScalabilityStructureL3T3Key() : ScalabilityStructureKeySvc(3, 3) {}
+  ~ScalabilityStructureL3T3Key() override;
+
+  FrameDependencyStructure DependencyStructure() const override;
+};
+
+}  // namespace webrtc
+
+#endif  // MODULES_VIDEO_CODING_SVC_SCALABILITY_STRUCTURE_KEY_SVC_H_