webrtc/modules/audio_processing/aec3/render_delay_buffer.h
Per Åhgren c59a576c86 Corrections of the render buffering scheme in AEC3 to ensure causality
This CL modifies the refactored render buffering scheme in AEC3
so that:
-A non-causal state can never occur which means that situations with
 nonrecoverable echo should not occur.
-For a stable audio pipeline with a predefined API call jitter,
 render overruns and underruns can never occur.

Bug: webrtc:8629,chromium:793305
Change-Id: I06ba1c368f92db95274090b08475dd02dbb85145
Reviewed-on: https://webrtc-review.googlesource.com/29861
Commit-Queue: Per Åhgren <peah@webrtc.org>
Reviewed-by: Gustaf Ullberg <gustaf@webrtc.org>
Cr-Commit-Position: refs/heads/master@{#21215}
2017-12-11 21:09:56 +00:00

79 lines
2.6 KiB
C++

/*
* Copyright (c) 2017 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.
*/
#ifndef MODULES_AUDIO_PROCESSING_AEC3_RENDER_DELAY_BUFFER_H_
#define MODULES_AUDIO_PROCESSING_AEC3_RENDER_DELAY_BUFFER_H_
#include <stddef.h>
#include <array>
#include <vector>
#include "api/array_view.h"
#include "modules/audio_processing/aec3/aec3_common.h"
#include "modules/audio_processing/aec3/downsampled_render_buffer.h"
#include "modules/audio_processing/aec3/fft_data.h"
#include "modules/audio_processing/aec3/render_buffer.h"
#include "modules/audio_processing/include/audio_processing.h"
namespace webrtc {
// Class for buffering the incoming render blocks such that these may be
// extracted with a specified delay.
class RenderDelayBuffer {
public:
enum class BufferingEvent {
kNone,
kRenderUnderrun,
kRenderOverrun,
kApiCallSkew,
kRenderDataLost
};
static RenderDelayBuffer* Create(const EchoCanceller3Config& config,
size_t num_bands);
virtual ~RenderDelayBuffer() = default;
// Resets the buffer alignment.
virtual void Reset() = 0;
// Inserts a block into the buffer.
virtual BufferingEvent Insert(
const std::vector<std::vector<float>>& block) = 0;
// Updates the buffers one step based on the specified buffer delay. Returns
// an enum indicating whether there was a special event that occurred.
virtual BufferingEvent PrepareCaptureProcessing() = 0;
// Sets the buffer delay and returns a bool indicating whether the delay
// changed.
virtual bool SetDelay(size_t delay) = 0;
// Gets the buffer delay.
virtual rtc::Optional<size_t> Delay() const = 0;
// Gets the buffer delay.
virtual size_t MaxDelay() const = 0;
// Returns the render buffer for the echo remover.
virtual RenderBuffer* GetRenderBuffer() = 0;
// Returns the downsampled render buffer.
virtual const DownsampledRenderBuffer& GetDownsampledRenderBuffer() const = 0;
// Returns whether the current delay is noncausal.
virtual bool CausalDelay() const = 0;
// Returns the maximum non calusal offset that can occur in the delay buffer.
static int DelayEstimatorOffset(const EchoCanceller3Config& config);
};
} // namespace webrtc
#endif // MODULES_AUDIO_PROCESSING_AEC3_RENDER_DELAY_BUFFER_H_