gecko/content/media/AudioNodeExternalInputStream.h

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/* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*-*/
/* This Source Code Form is subject to the terms of the Mozilla Public
* License, v. 2.0. If a copy of the MPL was not distributed with this file,
* You can obtain one at http://mozilla.org/MPL/2.0/. */
#ifndef MOZILLA_AUDIONODEEXTERNALINPUTSTREAM_H_
#define MOZILLA_AUDIONODEEXTERNALINPUTSTREAM_H_
#include "MediaStreamGraph.h"
#include "AudioNodeStream.h"
#ifdef PR_LOGGING
#define LOG(type, msg) PR_LOG(gMediaStreamGraphLog, type, msg)
#else
#define LOG(type, msg)
#endif
// Forward declaration for mResamplerMap
typedef struct SpeexResamplerState_ SpeexResamplerState;
namespace mozilla {
/**
* This is a MediaStream implementation that acts for a Web Audio node but
* unlike other AudioNodeStreams, supports any kind of MediaStream as an
* input --- handling any number of audio tracks, resampling them from whatever
* sample rate they're using, and handling blocking of the input MediaStream.
*/
class AudioNodeExternalInputStream : public AudioNodeStream {
public:
AudioNodeExternalInputStream(AudioNodeEngine* aEngine, TrackRate aSampleRate);
~AudioNodeExternalInputStream();
virtual void ProduceOutput(GraphTime aFrom, GraphTime aTo) MOZ_OVERRIDE;
private:
// For storing pointers and data about input tracks, like the last TrackTick which
// was read, and the associated speex resampler.
struct TrackMapEntry {
~TrackMapEntry();
/**
* Resamples data from all chunks in aIterator and following, using mResampler,
* adding the results to mResampledData.
*/
void ResampleInputData(AudioSegment* aSegment);
/**
* Resamples a set of channel buffers using mResampler, adding the results
* to mResampledData.
*/
void ResampleChannels(const nsTArray<const void*>& aBuffers,
uint32_t aInputDuration,
AudioSampleFormat aFormat,
float aVolume);
// mEndOfConsumedInputTicks is the end of the input ticks that we've consumed.
// 0 if we haven't consumed any yet.
TrackTicks mEndOfConsumedInputTicks;
// mEndOfLastInputIntervalInInputStream is the timestamp for the end of the
// previous interval which was unblocked for both the input and output
// stream, in the input stream's timeline, or -1 if there wasn't one.
StreamTime mEndOfLastInputIntervalInInputStream;
// mEndOfLastInputIntervalInOutputStream is the timestamp for the end of the
// previous interval which was unblocked for both the input and output
// stream, in the output stream's timeline, or -1 if there wasn't one.
StreamTime mEndOfLastInputIntervalInOutputStream;
/**
* Number of samples passed to the resampler so far.
*/
TrackTicks mSamplesPassedToResampler;
/**
* Resampler being applied to this track.
*/
SpeexResamplerState* mResampler;
/**
* The track data that has been resampled to the rate of the
* AudioNodeExternalInputStream. All data in these chunks is in floats (or null),
* and has the number of channels given in mResamplerChannelCount.
* mResampledData starts at zero in the stream's output track (so generally
* it will consist of null data followed by actual data).
*/
AudioSegment mResampledData;
/**
* Number of channels used to create mResampler.
*/
uint32_t mResamplerChannelCount;
/**
* The ID for the track of the input stream this entry is for.
*/
TrackID mTrackID;
};
nsTArray<TrackMapEntry> mTrackMap;
// Amount of track data produced so far. A multiple of WEBAUDIO_BLOCK_SIZE.
TrackTicks mCurrentOutputPosition;
/**
* Creates a TrackMapEntry for the track, if needed. Returns the index
* of the TrackMapEntry or NoIndex if no entry is needed yet.
*/
uint32_t GetTrackMapEntry(const StreamBuffer::Track& aTrack,
GraphTime aFrom);
};
}
#endif /* MOZILLA_AUDIONODESTREAM_H_ */