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/*
Copyright 2018 Google Inc. All Rights Reserved.
Licensed under the Apache License, Version 2.0 (the "License");
you may not use this file except in compliance with the License.
You may obtain a copy of the License at
Unless required by applicable law or agreed to in writing, software
distributed under the License is distributed on an "AS-IS" BASIS,
WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
See the License for the specific language governing permissions and
limitations under the License.
*/
// Prevent Visual Studio from complaining about std::copy_n.
#if defined(_WIN32)
#define _SCL_SECURE_NO_WARNINGS
#endif
#include "utils/buffer_unpartitioner.h"
#include "utils/planar_interleaved_conversion.h"
#include "utils/sample_type_conversion.h"
namespace vraudio {
BufferUnpartitioner::BufferUnpartitioner(size_t num_channels,
size_t frames_per_buffer,
GetBufferCallback buffer_callback)
: num_channels_(num_channels),
frames_per_buffer_(frames_per_buffer),
buffer_callback_(std::move(buffer_callback)),
current_input_buffer_(nullptr),
current_buffer_read_offset_frames_(0) {
DCHECK_GT(frames_per_buffer_, 0);
DCHECK_GT(num_channels, 0);
}
size_t BufferUnpartitioner::GetNumBuffersRequestedForNumInputFrames(
size_t num_output_frames) const {
if (num_output_frames == 0) {
return 0;
}
return (num_output_frames - GetNumFramesAvailableInBuffer() +
frames_per_buffer_ - 1) /
frames_per_buffer_;
}
size_t BufferUnpartitioner::GetBuffer(int16* output_buffer, size_t num_channels,
size_t num_frames) {
return GetBufferTemplated<int16*>(output_buffer, num_channels, num_frames);
}
size_t BufferUnpartitioner::GetBuffer(float* output_buffer, size_t num_channels,
size_t num_frames) {
return GetBufferTemplated<float*>(output_buffer, num_channels, num_frames);
}
size_t BufferUnpartitioner::GetBuffer(int16** output_buffer,
size_t num_channels, size_t num_frames) {
return GetBufferTemplated<int16**>(output_buffer, num_channels, num_frames);
}
size_t BufferUnpartitioner::GetBuffer(float** output_buffer,
size_t num_channels, size_t num_frames) {
return GetBufferTemplated<float**>(output_buffer, num_channels, num_frames);
}
size_t BufferUnpartitioner::GetNumBufferedFrames() const {
return current_buffer_read_offset_frames_;
}
size_t BufferUnpartitioner::GetNumFramesAvailableInBuffer() const {
if (current_input_buffer_ == nullptr) {
return 0;
}
DCHECK_GE(current_input_buffer_->num_frames(),
current_buffer_read_offset_frames_);
return current_input_buffer_->num_frames() -
current_buffer_read_offset_frames_;
}
void BufferUnpartitioner::Clear() {
current_input_buffer_ = nullptr;
current_buffer_read_offset_frames_ = 0;
}
template <typename BufferType>
size_t BufferUnpartitioner::GetBufferTemplated(BufferType buffer,
size_t num_channels,
size_t num_frames) {
DCHECK_EQ(num_channels, num_channels_);
size_t num_copied_frames = 0;
while (num_copied_frames < num_frames) {
if (current_input_buffer_ == nullptr) {
current_input_buffer_ = buffer_callback_();
if (current_input_buffer_ == nullptr) {
// No more input |AudioBuffer|s are available.
return num_copied_frames;
}
DCHECK_EQ(frames_per_buffer_, current_input_buffer_->num_frames());
current_buffer_read_offset_frames_ = 0;
}
DCHECK_GE(frames_per_buffer_, current_buffer_read_offset_frames_);
const size_t remaining_frames_in_input_buffer =
num_frames - num_copied_frames;
DCHECK_GE(current_input_buffer_->num_frames(),
current_buffer_read_offset_frames_);
const size_t num_frames_to_process =
std::min(current_input_buffer_->num_frames() -
current_buffer_read_offset_frames_,
remaining_frames_in_input_buffer);
FillExternalBufferWithOffset(
*current_input_buffer_, current_buffer_read_offset_frames_, buffer,
num_frames, num_channels, num_copied_frames, num_frames_to_process);
num_copied_frames += num_frames_to_process;
current_buffer_read_offset_frames_ += num_frames_to_process;
if (current_buffer_read_offset_frames_ ==
current_input_buffer_->num_frames()) {
current_input_buffer_ = nullptr;
}
}
return num_copied_frames;
}
} // namespace vraudio