1 /* 2 * Copyright (c) 2013 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 "webrtc/common_audio/resampler/include/push_resampler.h" 12 13 #include <string.h> 14 15 #include "webrtc/common_audio/include/audio_util.h" 16 #include "webrtc/common_audio/resampler/include/resampler.h" 17 #include "webrtc/common_audio/resampler/push_sinc_resampler.h" 18 19 namespace webrtc { 20 21 template <typename T> 22 PushResampler<T>::PushResampler() 23 : src_sample_rate_hz_(0), 24 dst_sample_rate_hz_(0), 25 num_channels_(0) { 26 } 27 28 template <typename T> 29 PushResampler<T>::~PushResampler() { 30 } 31 32 template <typename T> 33 int PushResampler<T>::InitializeIfNeeded(int src_sample_rate_hz, 34 int dst_sample_rate_hz, 35 size_t num_channels) { 36 if (src_sample_rate_hz == src_sample_rate_hz_ && 37 dst_sample_rate_hz == dst_sample_rate_hz_ && 38 num_channels == num_channels_) 39 // No-op if settings haven't changed. 40 return 0; 41 42 if (src_sample_rate_hz <= 0 || dst_sample_rate_hz <= 0 || 43 num_channels <= 0 || num_channels > 2) 44 return -1; 45 46 src_sample_rate_hz_ = src_sample_rate_hz; 47 dst_sample_rate_hz_ = dst_sample_rate_hz; 48 num_channels_ = num_channels; 49 50 const size_t src_size_10ms_mono = 51 static_cast<size_t>(src_sample_rate_hz / 100); 52 const size_t dst_size_10ms_mono = 53 static_cast<size_t>(dst_sample_rate_hz / 100); 54 sinc_resampler_.reset(new PushSincResampler(src_size_10ms_mono, 55 dst_size_10ms_mono)); 56 if (num_channels_ == 2) { 57 src_left_.reset(new T[src_size_10ms_mono]); 58 src_right_.reset(new T[src_size_10ms_mono]); 59 dst_left_.reset(new T[dst_size_10ms_mono]); 60 dst_right_.reset(new T[dst_size_10ms_mono]); 61 sinc_resampler_right_.reset(new PushSincResampler(src_size_10ms_mono, 62 dst_size_10ms_mono)); 63 } 64 65 return 0; 66 } 67 68 template <typename T> 69 int PushResampler<T>::Resample(const T* src, size_t src_length, T* dst, 70 size_t dst_capacity) { 71 const size_t src_size_10ms = src_sample_rate_hz_ * num_channels_ / 100; 72 const size_t dst_size_10ms = dst_sample_rate_hz_ * num_channels_ / 100; 73 if (src_length != src_size_10ms || dst_capacity < dst_size_10ms) 74 return -1; 75 76 if (src_sample_rate_hz_ == dst_sample_rate_hz_) { 77 // The old resampler provides this memcpy facility in the case of matching 78 // sample rates, so reproduce it here for the sinc resampler. 79 memcpy(dst, src, src_length * sizeof(T)); 80 return static_cast<int>(src_length); 81 } 82 if (num_channels_ == 2) { 83 const size_t src_length_mono = src_length / num_channels_; 84 const size_t dst_capacity_mono = dst_capacity / num_channels_; 85 T* deinterleaved[] = {src_left_.get(), src_right_.get()}; 86 Deinterleave(src, src_length_mono, num_channels_, deinterleaved); 87 88 size_t dst_length_mono = 89 sinc_resampler_->Resample(src_left_.get(), src_length_mono, 90 dst_left_.get(), dst_capacity_mono); 91 sinc_resampler_right_->Resample(src_right_.get(), src_length_mono, 92 dst_right_.get(), dst_capacity_mono); 93 94 deinterleaved[0] = dst_left_.get(); 95 deinterleaved[1] = dst_right_.get(); 96 Interleave(deinterleaved, dst_length_mono, num_channels_, dst); 97 return static_cast<int>(dst_length_mono * num_channels_); 98 } else { 99 return static_cast<int>( 100 sinc_resampler_->Resample(src, src_length, dst, dst_capacity)); 101 } 102 } 103 104 // Explictly generate required instantiations. 105 template class PushResampler<int16_t>; 106 template class PushResampler<float>; 107 108 } // namespace webrtc 109
