1 files changed, 69 insertions, 0 deletions
diff --git a/third_party/libwebrtc/modules/rtp_rtcp/source/rtp_dependency_descriptor_reader.h b/third_party/libwebrtc/modules/rtp_rtcp/source/rtp_dependency_descriptor_reader.h
new file mode 100644
index 0000000000..f79d3d1d07
--- /dev/null
+++ b/third_party/libwebrtc/modules/rtp_rtcp/source/rtp_dependency_descriptor_reader.h
@@ -0,0 +1,69 @@
+/*
+ *  Copyright (c) 2019 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_RTP_RTCP_SOURCE_RTP_DEPENDENCY_DESCRIPTOR_READER_H_
+#define MODULES_RTP_RTCP_SOURCE_RTP_DEPENDENCY_DESCRIPTOR_READER_H_
+
+#include <cstdint>
+#include <memory>
+#include <vector>
+
+#include "api/array_view.h"
+#include "api/transport/rtp/dependency_descriptor.h"
+#include "rtc_base/bitstream_reader.h"
+
+namespace webrtc {
+// Deserializes DependencyDescriptor rtp header extension.
+class RtpDependencyDescriptorReader {
+ public:
+  // Parses the dependency descriptor.
+  RtpDependencyDescriptorReader(rtc::ArrayView<const uint8_t> raw_data,
+                                const FrameDependencyStructure* structure,
+                                DependencyDescriptor* descriptor);
+  RtpDependencyDescriptorReader(const RtpDependencyDescriptorReader&) = delete;
+  RtpDependencyDescriptorReader& operator=(
+      const RtpDependencyDescriptorReader&) = delete;
+
+  // Returns true if parse was successful.
+  bool ParseSuccessful() { return buffer_.Ok(); }
+
+ private:
+  // Functions to read template dependency structure.
+  void ReadTemplateDependencyStructure();
+  void ReadTemplateLayers();
+  void ReadTemplateDtis();
+  void ReadTemplateFdiffs();
+  void ReadTemplateChains();
+  void ReadResolutions();
+
+  // Function to read details for the current frame.
+  void ReadMandatoryFields();
+  void ReadExtendedFields();
+  void ReadFrameDependencyDefinition();
+
+  void ReadFrameDtis();
+  void ReadFrameFdiffs();
+  void ReadFrameChains();
+
+  // Output.
+  DependencyDescriptor* const descriptor_;
+  // Values that are needed while reading the descriptor, but can be discarded
+  // when reading is complete.
+  BitstreamReader buffer_;
+  int frame_dependency_template_id_ = 0;
+  bool active_decode_targets_present_flag_ = false;
+  bool custom_dtis_flag_ = false;
+  bool custom_fdiffs_flag_ = false;
+  bool custom_chains_flag_ = false;
+  const FrameDependencyStructure* structure_ = nullptr;
+};
+
+}  // namespace webrtc
+
+#endif  // MODULES_RTP_RTCP_SOURCE_RTP_DEPENDENCY_DESCRIPTOR_READER_H_