blob: 5ab1db1b2586142631768f5625014b894f5749fa [file] [log] [blame]
/*
* Copyright (c) 2014 The WebRTC project authors. All Rights Reserved.
*
* Use of this source code is governed by a BSD-style license
* that can be found in the LICENSE file in the root of the source
* tree. An additional intellectual property rights grant can be found
* in the file PATENTS. All contributing project authors may
* be found in the AUTHORS file in the root of the source tree.
*/
#include "webrtc/common_audio/lapped_transform.h"
#include <algorithm>
#include <cstdlib>
#include <cstring>
#include "webrtc/base/checks.h"
#include "webrtc/common_audio/real_fourier.h"
namespace webrtc {
void LappedTransform::BlockThunk::ProcessBlock(const float* const* input,
size_t num_frames,
size_t num_input_channels,
size_t num_output_channels,
float* const* output) {
RTC_CHECK_EQ(num_input_channels, parent_->num_in_channels_);
RTC_CHECK_EQ(num_output_channels, parent_->num_out_channels_);
RTC_CHECK_EQ(parent_->block_length_, num_frames);
for (size_t i = 0; i < num_input_channels; ++i) {
memcpy(parent_->real_buf_.Row(i), input[i],
num_frames * sizeof(*input[0]));
parent_->fft_->Forward(parent_->real_buf_.Row(i),
parent_->cplx_pre_.Row(i));
}
size_t block_length = RealFourier::ComplexLength(
RealFourier::FftOrder(num_frames));
RTC_CHECK_EQ(parent_->cplx_length_, block_length);
parent_->block_processor_->ProcessAudioBlock(parent_->cplx_pre_.Array(),
num_input_channels,
parent_->cplx_length_,
num_output_channels,
parent_->cplx_post_.Array());
for (size_t i = 0; i < num_output_channels; ++i) {
parent_->fft_->Inverse(parent_->cplx_post_.Row(i),
parent_->real_buf_.Row(i));
memcpy(output[i], parent_->real_buf_.Row(i),
num_frames * sizeof(*input[0]));
}
}
LappedTransform::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)
: blocker_callback_(this),
num_in_channels_(num_in_channels),
num_out_channels_(num_out_channels),
block_length_(block_length),
chunk_length_(chunk_length),
block_processor_(callback),
blocker_(chunk_length_,
block_length_,
num_in_channels_,
num_out_channels_,
window,
shift_amount,
&blocker_callback_),
fft_(RealFourier::Create(RealFourier::FftOrder(block_length_))),
cplx_length_(RealFourier::ComplexLength(fft_->order())),
real_buf_(num_in_channels,
block_length_,
RealFourier::kFftBufferAlignment),
cplx_pre_(num_in_channels,
cplx_length_,
RealFourier::kFftBufferAlignment),
cplx_post_(num_out_channels,
cplx_length_,
RealFourier::kFftBufferAlignment) {
RTC_CHECK(num_in_channels_ > 0 && num_out_channels_ > 0);
RTC_CHECK_GT(block_length_, 0u);
RTC_CHECK_GT(chunk_length_, 0u);
RTC_CHECK(block_processor_);
// block_length_ power of 2?
RTC_CHECK_EQ(0u, block_length_ & (block_length_ - 1));
}
void LappedTransform::ProcessChunk(const float* const* in_chunk,
float* const* out_chunk) {
blocker_.ProcessChunk(in_chunk, chunk_length_, num_in_channels_,
num_out_channels_, out_chunk);
}
} // namespace webrtc