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>
PushResampler()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>
~PushResampler()29 PushResampler<T>::~PushResampler() {
30 }
31
32 template <typename T>
InitializeIfNeeded(int src_sample_rate_hz,int dst_sample_rate_hz,size_t num_channels)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>
Resample(const T * src,size_t src_length,T * dst,size_t dst_capacity)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