1 /* 2 * Copyright (c) 2012 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 WEBRTC_MODULES_AUDIO_CODING_NETEQ_BUFFER_LEVEL_FILTER_H_ 12 #define WEBRTC_MODULES_AUDIO_CODING_NETEQ_BUFFER_LEVEL_FILTER_H_ 13 14 #include <stddef.h> 15 16 #include "webrtc/base/constructormagic.h" 17 18 namespace webrtc { 19 20 class BufferLevelFilter { 21 public: 22 BufferLevelFilter(); 23 virtual ~BufferLevelFilter() {} 24 virtual void Reset(); 25 26 // Updates the filter. Current buffer size is |buffer_size_packets| (Q0). 27 // If |time_stretched_samples| is non-zero, the value is converted to the 28 // corresponding number of packets, and is subtracted from the filtered 29 // value (thus bypassing the filter operation). |packet_len_samples| is the 30 // number of audio samples carried in each incoming packet. 31 virtual void Update(size_t buffer_size_packets, int time_stretched_samples, 32 size_t packet_len_samples); 33 34 // Set the current target buffer level (obtained from 35 // DelayManager::base_target_level()). Used to select the appropriate 36 // filter coefficient. 37 virtual void SetTargetBufferLevel(int target_buffer_level); 38 39 virtual int filtered_current_level() const; 40 41 private: 42 int level_factor_; // Filter factor for the buffer level filter in Q8. 43 int filtered_current_level_; // Filtered current buffer level in Q8. 44 45 RTC_DISALLOW_COPY_AND_ASSIGN(BufferLevelFilter); 46 }; 47 48 } // namespace webrtc 49 #endif // WEBRTC_MODULES_AUDIO_CODING_NETEQ_BUFFER_LEVEL_FILTER_H_ 50
