1 /* 2 * Copyright (c) 2019 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 #ifndef MODULES_RTP_RTCP_SOURCE_RTP_DEPENDENCY_DESCRIPTOR_READER_H_ 11 #define MODULES_RTP_RTCP_SOURCE_RTP_DEPENDENCY_DESCRIPTOR_READER_H_ 12 13 #include <cstdint> 14 #include <memory> 15 #include <vector> 16 17 #include "api/array_view.h" 18 #include "api/transport/rtp/dependency_descriptor.h" 19 #include "rtc_base/bitstream_reader.h" 20 21 namespace webrtc { 22 // Deserializes DependencyDescriptor rtp header extension. 23 class RtpDependencyDescriptorReader { 24 public: 25 // Parses the dependency descriptor. 26 RtpDependencyDescriptorReader(rtc::ArrayView<const uint8_t> raw_data, 27 const FrameDependencyStructure* structure, 28 DependencyDescriptor* descriptor); 29 RtpDependencyDescriptorReader(const RtpDependencyDescriptorReader&) = delete; 30 RtpDependencyDescriptorReader& operator=( 31 const RtpDependencyDescriptorReader&) = delete; 32 33 // Returns true if parse was successful. ParseSuccessful()34 bool ParseSuccessful() { return buffer_.Ok(); } 35 36 private: 37 // Functions to read template dependency structure. 38 void ReadTemplateDependencyStructure(); 39 void ReadTemplateLayers(); 40 void ReadTemplateDtis(); 41 void ReadTemplateFdiffs(); 42 void ReadTemplateChains(); 43 void ReadResolutions(); 44 45 // Function to read details for the current frame. 46 void ReadMandatoryFields(); 47 void ReadExtendedFields(); 48 void ReadFrameDependencyDefinition(); 49 50 void ReadFrameDtis(); 51 void ReadFrameFdiffs(); 52 void ReadFrameChains(); 53 54 // Output. 55 DependencyDescriptor* const descriptor_; 56 // Values that are needed while reading the descriptor, but can be discarded 57 // when reading is complete. 58 BitstreamReader buffer_; 59 int frame_dependency_template_id_ = 0; 60 bool active_decode_targets_present_flag_ = false; 61 bool custom_dtis_flag_ = false; 62 bool custom_fdiffs_flag_ = false; 63 bool custom_chains_flag_ = false; 64 const FrameDependencyStructure* structure_ = nullptr; 65 }; 66 67 } // namespace webrtc 68 69 #endif // MODULES_RTP_RTCP_SOURCE_RTP_DEPENDENCY_DESCRIPTOR_READER_H_ 70