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