1 /* 2 * Copyright (c) 2022 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 #include "modules/audio_processing/transient/voice_probability_delay_unit.h" 12 13 #include <array> 14 15 #include "rtc_base/checks.h" 16 17 namespace webrtc { 18 VoiceProbabilityDelayUnit(int delay_num_samples,int sample_rate_hz)19VoiceProbabilityDelayUnit::VoiceProbabilityDelayUnit(int delay_num_samples, 20 int sample_rate_hz) { 21 Initialize(delay_num_samples, sample_rate_hz); 22 } 23 Initialize(int delay_num_samples,int sample_rate_hz)24void VoiceProbabilityDelayUnit::Initialize(int delay_num_samples, 25 int sample_rate_hz) { 26 RTC_DCHECK_GE(delay_num_samples, 0); 27 RTC_DCHECK_LE(delay_num_samples, sample_rate_hz / 50) 28 << "The implementation does not support delays greater than 20 ms."; 29 int frame_size = rtc::CheckedDivExact(sample_rate_hz, 100); // 10 ms. 30 if (delay_num_samples <= frame_size) { 31 weights_[0] = 0.0f; 32 weights_[1] = static_cast<float>(delay_num_samples) / frame_size; 33 weights_[2] = 34 static_cast<float>(frame_size - delay_num_samples) / frame_size; 35 } else { 36 delay_num_samples -= frame_size; 37 weights_[0] = static_cast<float>(delay_num_samples) / frame_size; 38 weights_[1] = 39 static_cast<float>(frame_size - delay_num_samples) / frame_size; 40 weights_[2] = 0.0f; 41 } 42 43 // Resets the delay unit. 44 last_probabilities_.fill(0.0f); 45 } 46 Delay(float voice_probability)47float VoiceProbabilityDelayUnit::Delay(float voice_probability) { 48 float weighted_probability = weights_[0] * last_probabilities_[0] + 49 weights_[1] * last_probabilities_[1] + 50 weights_[2] * voice_probability; 51 last_probabilities_[0] = last_probabilities_[1]; 52 last_probabilities_[1] = voice_probability; 53 return weighted_probability; 54 } 55 56 } // namespace webrtc 57