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 11 #ifndef MODULES_VIDEO_CODING_CHAIN_DIFF_CALCULATOR_H_ 12 #define MODULES_VIDEO_CODING_CHAIN_DIFF_CALCULATOR_H_ 13 14 #include <stdint.h> 15 16 #include <vector> 17 18 #include "absl/container/inlined_vector.h" 19 #include "absl/types/optional.h" 20 21 namespace webrtc { 22 23 // This class is thread compatible. 24 class ChainDiffCalculator { 25 public: 26 ChainDiffCalculator() = default; 27 ChainDiffCalculator(const ChainDiffCalculator&) = default; 28 ChainDiffCalculator& operator=(const ChainDiffCalculator&) = default; 29 30 // Restarts chains, i.e. for position where chains[i] == true next chain_diff 31 // will be 0. Saves chains.size() as number of chains in the stream. 32 void Reset(const std::vector<bool>& chains); 33 34 // Returns chain diffs based on flags if frame is part of the chain. 35 absl::InlinedVector<int, 4> From(int64_t frame_id, 36 const std::vector<bool>& chains); 37 38 private: 39 absl::InlinedVector<int, 4> ChainDiffs(int64_t frame_id) const; 40 41 absl::InlinedVector<absl::optional<int64_t>, 4> last_frame_in_chain_; 42 }; 43 44 } // namespace webrtc 45 46 #endif // MODULES_VIDEO_CODING_CHAIN_DIFF_CALCULATOR_H_ 47