chromium/media/base/audio_bus.h

// Copyright 2012 The Chromium Authors
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.

#ifdef UNSAFE_BUFFERS_BUILD
// TODO(crbug.com/40285824): Remove this and convert code to safer constructs.
#pragma allow_unsafe_buffers
#endif

#ifndef MEDIA_BASE_AUDIO_BUS_H_
#define MEDIA_BASE_AUDIO_BUS_H_

#include <stdint.h>

#include <memory>
#include <vector>

#include "base/functional/callback.h"
#include "base/memory/aligned_memory.h"
#include "base/memory/raw_ptr.h"
#include "media/base/audio_sample_types.h"
#include "media/base/media_shmem_export.h"

namespace media {
class AudioParameters;

// Represents a sequence of audio frames containing frames() audio samples for
// each of channels() channels. The data is stored as a set of contiguous
// float arrays with one array per channel. The memory for the arrays is either
// allocated and owned by the AudioBus or it is provided to one of the factory
// methods. AudioBus guarantees that it allocates memory such that float array
// for each channel is aligned by AudioBus::kChannelAlignment bytes and it
// requires the same for memory passed to its Wrap...() factory methods.
class MEDIA_SHMEM_EXPORT AudioBus { … };

// Delegates to FromInterleavedPartial()
template <class SourceSampleTypeTraits>
void AudioBus::FromInterleaved(
    const typename SourceSampleTypeTraits::ValueType* source_buffer,
    int num_frames_to_write) { … }

template <class SourceSampleTypeTraits>
void AudioBus::FromInterleavedPartial(
    const typename SourceSampleTypeTraits::ValueType* source_buffer,
    int write_offset_in_frames,
    int num_frames_to_write) { … }

// Delegates to ToInterleavedPartial()
template <class TargetSampleTypeTraits>
void AudioBus::ToInterleaved(
    int num_frames_to_read,
    typename TargetSampleTypeTraits::ValueType* dest_buffer) const { … }

template <class TargetSampleTypeTraits>
void AudioBus::ToInterleavedPartial(
    int read_offset_in_frames,
    int num_frames_to_read,
    typename TargetSampleTypeTraits::ValueType* dest) const { … }

// TODO(chfremer): Consider using vector instructions to speed this up,
//                 https://crbug.com/619628
template <class SourceSampleTypeTraits>
void AudioBus::CopyConvertFromInterleavedSourceToAudioBus(
    const typename SourceSampleTypeTraits::ValueType* source_buffer,
    int write_offset_in_frames,
    int num_frames_to_write,
    AudioBus* dest) { … }

// TODO(chfremer): Consider using vector instructions to speed this up,
//                 https://crbug.com/619628
template <class TargetSampleTypeTraits>
void AudioBus::CopyConvertFromAudioBusToInterleavedTarget(
    const AudioBus* source,
    int read_offset_in_frames,
    int num_frames_to_read,
    typename TargetSampleTypeTraits::ValueType* dest_buffer) { … }

}  // namespace media

#endif  // MEDIA_BASE_AUDIO_BUS_H_