1 /*
2 * Copyright (c) 2014 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_coding/codecs/opus/test/lapped_transform.h"
12
13 #include <algorithm>
14 #include <cstdlib>
15 #include <cstring>
16
17 #include "common_audio/real_fourier.h"
18 #include "rtc_base/checks.h"
19
20 namespace webrtc {
21
ProcessBlock(const float * const * input,size_t num_frames,size_t num_input_channels,size_t num_output_channels,float * const * output)22 void LappedTransform::BlockThunk::ProcessBlock(const float* const* input,
23 size_t num_frames,
24 size_t num_input_channels,
25 size_t num_output_channels,
26 float* const* output) {
27 RTC_CHECK_EQ(num_input_channels, parent_->num_in_channels_);
28 RTC_CHECK_EQ(num_output_channels, parent_->num_out_channels_);
29 RTC_CHECK_EQ(parent_->block_length_, num_frames);
30
31 for (size_t i = 0; i < num_input_channels; ++i) {
32 memcpy(parent_->real_buf_.Row(i), input[i], num_frames * sizeof(*input[0]));
33 parent_->fft_->Forward(parent_->real_buf_.Row(i),
34 parent_->cplx_pre_.Row(i));
35 }
36
37 size_t block_length =
38 RealFourier::ComplexLength(RealFourier::FftOrder(num_frames));
39 RTC_CHECK_EQ(parent_->cplx_length_, block_length);
40 parent_->block_processor_->ProcessAudioBlock(
41 parent_->cplx_pre_.Array(), num_input_channels, parent_->cplx_length_,
42 num_output_channels, parent_->cplx_post_.Array());
43
44 for (size_t i = 0; i < num_output_channels; ++i) {
45 parent_->fft_->Inverse(parent_->cplx_post_.Row(i),
46 parent_->real_buf_.Row(i));
47 memcpy(output[i], parent_->real_buf_.Row(i),
48 num_frames * sizeof(*input[0]));
49 }
50 }
51
LappedTransform(size_t num_in_channels,size_t num_out_channels,size_t chunk_length,const float * window,size_t block_length,size_t shift_amount,Callback * callback)52 LappedTransform::LappedTransform(size_t num_in_channels,
53 size_t num_out_channels,
54 size_t chunk_length,
55 const float* window,
56 size_t block_length,
57 size_t shift_amount,
58 Callback* callback)
59 : blocker_callback_(this),
60 num_in_channels_(num_in_channels),
61 num_out_channels_(num_out_channels),
62 block_length_(block_length),
63 chunk_length_(chunk_length),
64 block_processor_(callback),
65 blocker_(chunk_length_,
66 block_length_,
67 num_in_channels_,
68 num_out_channels_,
69 window,
70 shift_amount,
71 &blocker_callback_),
72 fft_(RealFourier::Create(RealFourier::FftOrder(block_length_))),
73 cplx_length_(RealFourier::ComplexLength(fft_->order())),
74 real_buf_(num_in_channels,
75 block_length_,
76 RealFourier::kFftBufferAlignment),
77 cplx_pre_(num_in_channels,
78 cplx_length_,
79 RealFourier::kFftBufferAlignment),
80 cplx_post_(num_out_channels,
81 cplx_length_,
82 RealFourier::kFftBufferAlignment) {
83 RTC_CHECK(num_in_channels_ > 0);
84 RTC_CHECK_GT(block_length_, 0);
85 RTC_CHECK_GT(chunk_length_, 0);
86 RTC_CHECK(block_processor_);
87
88 // block_length_ power of 2?
89 RTC_CHECK_EQ(0, block_length_ & (block_length_ - 1));
90 }
91
92 LappedTransform::~LappedTransform() = default;
93
ProcessChunk(const float * const * in_chunk,float * const * out_chunk)94 void LappedTransform::ProcessChunk(const float* const* in_chunk,
95 float* const* out_chunk) {
96 blocker_.ProcessChunk(in_chunk, chunk_length_, num_in_channels_,
97 num_out_channels_, out_chunk);
98 }
99
100 } // namespace webrtc
101