| /* |
| * Copyright (c) 2012 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_CODING_NETEQ_BUFFER_LEVEL_FILTER_H_ |
| #define MODULES_AUDIO_CODING_NETEQ_BUFFER_LEVEL_FILTER_H_ |
| |
| #include <stddef.h> |
| #include <stdint.h> |
| |
| #include "rtc_base/constructor_magic.h" |
| |
| namespace webrtc { |
| |
| class BufferLevelFilter { |
| public: |
| BufferLevelFilter(); |
| virtual ~BufferLevelFilter() {} |
| virtual void Reset(); |
| |
| // Updates the filter. Current buffer size is `buffer_size_samples`. |
| // `time_stretched_samples` is subtracted from the filtered value (thus |
| // bypassing the filter operation). |
| virtual void Update(size_t buffer_size_samples, int time_stretched_samples); |
| |
| // Set the filtered buffer level to a particular value directly. This should |
| // only be used in case of large changes in buffer size, such as buffer |
| // flushes. |
| virtual void SetFilteredBufferLevel(int buffer_size_samples); |
| |
| // The target level is used to select the appropriate filter coefficient. |
| virtual void SetTargetBufferLevel(int target_buffer_level_ms); |
| |
| // Returns filtered current level in number of samples. |
| virtual int filtered_current_level() const { |
| // Round to nearest whole sample. |
| return (int64_t{filtered_current_level_} + (1 << 7)) >> 8; |
| } |
| |
| private: |
| int level_factor_; // Filter factor for the buffer level filter in Q8. |
| int filtered_current_level_; // Filtered current buffer level in Q8. |
| |
| RTC_DISALLOW_COPY_AND_ASSIGN(BufferLevelFilter); |
| }; |
| |
| } // namespace webrtc |
| #endif // MODULES_AUDIO_CODING_NETEQ_BUFFER_LEVEL_FILTER_H_ |