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/*
* Copyright (c) 2012 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 "modules/audio_coding/neteq/audio_vector.h"
#include <algorithm>
#include <memory>
#include "rtc_base/checks.h"
namespace webrtc {
AudioVector::AudioVector() : AudioVector(kDefaultInitialSize) {
Clear();
}
AudioVector::AudioVector(size_t initial_size)
: array_(new int16_t[initial_size + 1]),
capacity_(initial_size + 1),
begin_index_(0),
end_index_(capacity_ - 1) {
memset(array_.get(), 0, capacity_ * sizeof(int16_t));
}
AudioVector::~AudioVector() = default;
void AudioVector::Clear() {
end_index_ = begin_index_ = 0;
}
void AudioVector::CopyTo(AudioVector* copy_to) const {
RTC_DCHECK(copy_to);
copy_to->Reserve(Size());
CopyTo(Size(), 0, copy_to->array_.get());
copy_to->begin_index_ = 0;
copy_to->end_index_ = Size();
}
void AudioVector::CopyTo(size_t length,
size_t position,
int16_t* copy_to) const {
if (length == 0)
return;
length = std::min(length, Size() - position);
const size_t copy_index = (begin_index_ + position) % capacity_;
const size_t first_chunk_length = std::min(length, capacity_ - copy_index);
memcpy(copy_to, &array_[copy_index], first_chunk_length * sizeof(int16_t));
const size_t remaining_length = length - first_chunk_length;
if (remaining_length > 0) {
memcpy(©_to[first_chunk_length], array_.get(),
remaining_length * sizeof(int16_t));
}
}
void AudioVector::PushFront(const AudioVector& prepend_this) {
const size_t length = prepend_this.Size();
if (length == 0)
return;
// Although the subsequent calling to PushFront does Reserve in it, it is
// always more efficient to do a big Reserve first.
Reserve(Size() + length);
const size_t first_chunk_length =
std::min(length, prepend_this.capacity_ - prepend_this.begin_index_);
const size_t remaining_length = length - first_chunk_length;
if (remaining_length > 0)
PushFront(prepend_this.array_.get(), remaining_length);
PushFront(&prepend_this.array_[prepend_this.begin_index_],
first_chunk_length);
}
void AudioVector::PushFront(const int16_t* prepend_this, size_t length) {
if (length == 0)
return;
Reserve(Size() + length);
const size_t first_chunk_length = std::min(length, begin_index_);
memcpy(&array_[begin_index_ - first_chunk_length],
&prepend_this[length - first_chunk_length],
first_chunk_length * sizeof(int16_t));
const size_t remaining_length = length - first_chunk_length;
if (remaining_length > 0) {
memcpy(&array_[capacity_ - remaining_length], prepend_this,
remaining_length * sizeof(int16_t));
}
begin_index_ = (begin_index_ + capacity_ - length) % capacity_;
}
void AudioVector::PushBack(const AudioVector& append_this) {
PushBack(append_this, append_this.Size(), 0);
}
void AudioVector::PushBack(const AudioVector& append_this,
size_t length,
size_t position) {
RTC_DCHECK_LE(position, append_this.Size());
RTC_DCHECK_LE(length, append_this.Size() - position);
if (length == 0)
return;
// Although the subsequent calling to PushBack does Reserve in it, it is
// always more efficient to do a big Reserve first.
Reserve(Size() + length);
const size_t start_index =
(append_this.begin_index_ + position) % append_this.capacity_;
const size_t first_chunk_length =
std::min(length, append_this.capacity_ - start_index);
PushBack(&append_this.array_[start_index], first_chunk_length);
const size_t remaining_length = length - first_chunk_length;
if (remaining_length > 0)
PushBack(append_this.array_.get(), remaining_length);
}
void AudioVector::PushBack(const int16_t* append_this, size_t length) {
if (length == 0)
return;
Reserve(Size() + length);
const size_t first_chunk_length = std::min(length, capacity_ - end_index_);
memcpy(&array_[end_index_], append_this,
first_chunk_length * sizeof(int16_t));
const size_t remaining_length = length - first_chunk_length;
if (remaining_length > 0) {
memcpy(array_.get(), &append_this[first_chunk_length],
remaining_length * sizeof(int16_t));
}
end_index_ = (end_index_ + length) % capacity_;
}
void AudioVector::PopFront(size_t length) {
if (length == 0)
return;
length = std::min(length, Size());
begin_index_ = (begin_index_ + length) % capacity_;
}
void AudioVector::PopBack(size_t length) {
if (length == 0)
return;
// Never remove more than what is in the array.
length = std::min(length, Size());
end_index_ = (end_index_ + capacity_ - length) % capacity_;
}
void AudioVector::Extend(size_t extra_length) {
if (extra_length == 0)
return;
InsertZerosByPushBack(extra_length, Size());
}
void AudioVector::InsertAt(const int16_t* insert_this,
size_t length,
size_t position) {
if (length == 0)
return;
// Cap the insert position at the current array length.
position = std::min(Size(), position);
// When inserting to a position closer to the beginning, it is more efficient
// to insert by pushing front than to insert by pushing back, since less data
// will be moved, vice versa.
if (position <= Size() - position) {
InsertByPushFront(insert_this, length, position);
} else {
InsertByPushBack(insert_this, length, position);
}
}
void AudioVector::InsertZerosAt(size_t length, size_t position) {
if (length == 0)
return;
// Cap the insert position at the current array length.
position = std::min(Size(), position);
// When inserting to a position closer to the beginning, it is more efficient
// to insert by pushing front than to insert by pushing back, since less data
// will be moved, vice versa.
if (position <= Size() - position) {
InsertZerosByPushFront(length, position);
} else {
InsertZerosByPushBack(length, position);
}
}
void AudioVector::OverwriteAt(const AudioVector& insert_this,
size_t length,
size_t position) {
RTC_DCHECK_LE(length, insert_this.Size());
if (length == 0)
return;
// Cap the insert position at the current array length.
position = std::min(Size(), position);
// Although the subsequent calling to OverwriteAt does Reserve in it, it is
// always more efficient to do a big Reserve first.
size_t new_size = std::max(Size(), position + length);
Reserve(new_size);
const size_t first_chunk_length =
std::min(length, insert_this.capacity_ - insert_this.begin_index_);
OverwriteAt(&insert_this.array_[insert_this.begin_index_], first_chunk_length,
position);
const size_t remaining_length = length - first_chunk_length;
if (remaining_length > 0) {
OverwriteAt(insert_this.array_.get(), remaining_length,
position + first_chunk_length);
}
}
void AudioVector::OverwriteAt(const int16_t* insert_this,
size_t length,
size_t position) {
if (length == 0)
return;
// Cap the insert position at the current array length.
position = std::min(Size(), position);
size_t new_size = std::max(Size(), position + length);
Reserve(new_size);
const size_t overwrite_index = (begin_index_ + position) % capacity_;
const size_t first_chunk_length =
std::min(length, capacity_ - overwrite_index);
memcpy(&array_[overwrite_index], insert_this,
first_chunk_length * sizeof(int16_t));
const size_t remaining_length = length - first_chunk_length;
if (remaining_length > 0) {
memcpy(array_.get(), &insert_this[first_chunk_length],
remaining_length * sizeof(int16_t));
}
end_index_ = (begin_index_ + new_size) % capacity_;
}
void AudioVector::CrossFade(const AudioVector& append_this,
size_t fade_length) {
// Fade length cannot be longer than the current vector or `append_this`.
RTC_DCHECK_LE(fade_length, Size());
RTC_DCHECK_LE(fade_length, append_this.Size());
fade_length = std::min(fade_length, Size());
fade_length = std::min(fade_length, append_this.Size());
size_t position = Size() - fade_length + begin_index_;
// Cross fade the overlapping regions.
// `alpha` is the mixing factor in Q14.
// TODO(hlundin): Consider skipping +1 in the denominator to produce a
// smoother cross-fade, in particular at the end of the fade.
int alpha_step = 16384 / (static_cast<int>(fade_length) + 1);
int alpha = 16384;
for (size_t i = 0; i < fade_length; ++i) {
alpha -= alpha_step;
array_[(position + i) % capacity_] =
(alpha * array_[(position + i) % capacity_] +
(16384 - alpha) * append_this[i] + 8192) >>
14;
}
RTC_DCHECK_GE(alpha, 0); // Verify that the slope was correct.
// Append what is left of `append_this`.
size_t samples_to_push_back = append_this.Size() - fade_length;
if (samples_to_push_back > 0)
PushBack(append_this, samples_to_push_back, fade_length);
}
// Returns the number of elements in this AudioVector.
size_t AudioVector::Size() const {
return (end_index_ + capacity_ - begin_index_) % capacity_;
}
// Returns true if this AudioVector is empty.
bool AudioVector::Empty() const {
return begin_index_ == end_index_;
}
void AudioVector::Reserve(size_t n) {
if (capacity_ > n)
return;
const size_t length = Size();
// Reserve one more sample to remove the ambiguity between empty vector and
// full vector. Therefore `begin_index_` == `end_index_` indicates empty
// vector, and `begin_index_` == (`end_index_` + 1) % capacity indicates
// full vector.
std::unique_ptr<int16_t[]> temp_array(new int16_t[n + 1]);
CopyTo(length, 0, temp_array.get());
array_.swap(temp_array);
begin_index_ = 0;
end_index_ = length;
capacity_ = n + 1;
}
void AudioVector::InsertByPushBack(const int16_t* insert_this,
size_t length,
size_t position) {
const size_t move_chunk_length = Size() - position;
std::unique_ptr<int16_t[]> temp_array(nullptr);
if (move_chunk_length > 0) {
// TODO(minyue): see if it is possible to avoid copying to a buffer.
temp_array.reset(new int16_t[move_chunk_length]);
CopyTo(move_chunk_length, position, temp_array.get());
PopBack(move_chunk_length);
}
Reserve(Size() + length + move_chunk_length);
PushBack(insert_this, length);
if (move_chunk_length > 0)
PushBack(temp_array.get(), move_chunk_length);
}
void AudioVector::InsertByPushFront(const int16_t* insert_this,
size_t length,
size_t position) {
std::unique_ptr<int16_t[]> temp_array(nullptr);
if (position > 0) {
// TODO(minyue): see if it is possible to avoid copying to a buffer.
temp_array.reset(new int16_t[position]);
CopyTo(position, 0, temp_array.get());
PopFront(position);
}
Reserve(Size() + length + position);
PushFront(insert_this, length);
if (position > 0)
PushFront(temp_array.get(), position);
}
void AudioVector::InsertZerosByPushBack(size_t length, size_t position) {
const size_t move_chunk_length = Size() - position;
std::unique_ptr<int16_t[]> temp_array(nullptr);
if (move_chunk_length > 0) {
temp_array.reset(new int16_t[move_chunk_length]);
CopyTo(move_chunk_length, position, temp_array.get());
PopBack(move_chunk_length);
}
Reserve(Size() + length + move_chunk_length);
const size_t first_zero_chunk_length =
std::min(length, capacity_ - end_index_);
memset(&array_[end_index_], 0, first_zero_chunk_length * sizeof(int16_t));
const size_t remaining_zero_length = length - first_zero_chunk_length;
if (remaining_zero_length > 0)
memset(array_.get(), 0, remaining_zero_length * sizeof(int16_t));
end_index_ = (end_index_ + length) % capacity_;
if (move_chunk_length > 0)
PushBack(temp_array.get(), move_chunk_length);
}
void AudioVector::InsertZerosByPushFront(size_t length, size_t position) {
std::unique_ptr<int16_t[]> temp_array(nullptr);
if (position > 0) {
temp_array.reset(new int16_t[position]);
CopyTo(position, 0, temp_array.get());
PopFront(position);
}
Reserve(Size() + length + position);
const size_t first_zero_chunk_length = std::min(length, begin_index_);
memset(&array_[begin_index_ - first_zero_chunk_length], 0,
first_zero_chunk_length * sizeof(int16_t));
const size_t remaining_zero_length = length - first_zero_chunk_length;
if (remaining_zero_length > 0)
memset(&array_[capacity_ - remaining_zero_length], 0,
remaining_zero_length * sizeof(int16_t));
begin_index_ = (begin_index_ + capacity_ - length) % capacity_;
if (position > 0)
PushFront(temp_array.get(), position);
}
} // namespace webrtc
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