| /* |
| * Copyright (c) 2021 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_AUDIO_PROCESSING_AGC_CLIPPING_PREDICTOR_LEVEL_BUFFER_H_ |
| #define MODULES_AUDIO_PROCESSING_AGC_CLIPPING_PREDICTOR_LEVEL_BUFFER_H_ |
| |
| #include <memory> |
| #include <vector> |
| |
| #include "absl/types/optional.h" |
| |
| namespace webrtc { |
| |
| // A circular buffer to store frame-wise `Level` items for clipping prediction. |
| // The current implementation is not optimized for large buffer lengths. |
| class ClippingPredictorLevelBuffer { |
| public: |
| struct Level { |
| float average; |
| float max; |
| bool operator==(const Level& level) const; |
| }; |
| |
| // Recommended maximum capacity. It is possible to create a buffer with a |
| // larger capacity, but the implementation is not optimized for large values. |
| static constexpr int kMaxCapacity = 100; |
| |
| // Ctor. Sets the buffer capacity to max(1, `capacity`) and logs a warning |
| // message if the capacity is greater than `kMaxCapacity`. |
| explicit ClippingPredictorLevelBuffer(int capacity); |
| ~ClippingPredictorLevelBuffer() {} |
| ClippingPredictorLevelBuffer(const ClippingPredictorLevelBuffer&) = delete; |
| ClippingPredictorLevelBuffer& operator=(const ClippingPredictorLevelBuffer&) = |
| delete; |
| |
| void Reset(); |
| |
| // Returns the current number of items stored in the buffer. |
| int Size() const { return size_; } |
| |
| // Returns the capacity of the buffer. |
| int Capacity() const { return data_.size(); } |
| |
| // Adds a `level` item into the circular buffer `data_`. Stores at most |
| // `Capacity()` items. If more items are pushed, the new item replaces the |
| // least recently pushed item. |
| void Push(Level level); |
| |
| // If at least `num_items` + `delay` items have been pushed, returns the |
| // average and maximum value for the `num_items` most recently pushed items |
| // from `delay` to `delay` - `num_items` (a delay equal to zero corresponds |
| // to the most recently pushed item). The value of `delay` is limited to |
| // [0, N] and `num_items` to [1, M] where N + M is the capacity of the buffer. |
| absl::optional<Level> ComputePartialMetrics(int delay, int num_items) const; |
| |
| private: |
| int tail_; |
| int size_; |
| std::vector<Level> data_; |
| }; |
| |
| } // namespace webrtc |
| |
| #endif // MODULES_AUDIO_PROCESSING_AGC_CLIPPING_PREDICTOR_LEVEL_BUFFER_H_ |