michael@0: /* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*-*/
michael@0: /* This Source Code Form is subject to the terms of the Mozilla Public
michael@0:  * License, v. 2.0. If a copy of the MPL was not distributed with this file,
michael@0:  * You can obtain one at http://mozilla.org/MPL/2.0/. */
michael@0: 
michael@0: #ifndef OpusTrackEncoder_h_
michael@0: #define OpusTrackEncoder_h_
michael@0: 
michael@0: #include <stdint.h>
michael@0: #include <speex/speex_resampler.h>
michael@0: #include "TrackEncoder.h"
michael@0: 
michael@0: struct OpusEncoder;
michael@0: 
michael@0: namespace mozilla {
michael@0: 
michael@0: // Opus meta data structure
michael@0: class OpusMetadata : public TrackMetadataBase
michael@0: {
michael@0: public:
michael@0:   // The ID Header of OggOpus. refer to http://wiki.xiph.org/OggOpus.
michael@0:   nsTArray<uint8_t> mIdHeader;
michael@0:   // The Comment Header of OggOpus.
michael@0:   nsTArray<uint8_t> mCommentHeader;
michael@0: 
michael@0:   MetadataKind GetKind() const MOZ_OVERRIDE { return METADATA_OPUS; }
michael@0: };
michael@0: 
michael@0: class OpusTrackEncoder : public AudioTrackEncoder
michael@0: {
michael@0: public:
michael@0:   OpusTrackEncoder();
michael@0:   virtual ~OpusTrackEncoder();
michael@0: 
michael@0:   already_AddRefed<TrackMetadataBase> GetMetadata() MOZ_OVERRIDE;
michael@0: 
michael@0:   nsresult GetEncodedTrack(EncodedFrameContainer& aData) MOZ_OVERRIDE;
michael@0: 
michael@0: protected:
michael@0:   int GetPacketDuration();
michael@0: 
michael@0:   nsresult Init(int aChannels, int aSamplingRate) MOZ_OVERRIDE;
michael@0: 
michael@0:   /**
michael@0:    * Get the samplerate of the data to be fed to the Opus encoder. This might be
michael@0:    * different from the input samplerate if resampling occurs.
michael@0:    */
michael@0:   int GetOutputSampleRate();
michael@0: 
michael@0: private:
michael@0:   /**
michael@0:    * The Opus encoder from libopus.
michael@0:    */
michael@0:   OpusEncoder* mEncoder;
michael@0: 
michael@0:   /**
michael@0:    * A local segment queue which takes the raw data out from mRawSegment in the
michael@0:    * call of GetEncodedTrack(). Opus encoder only accepts GetPacketDuration()
michael@0:    * samples from mSourceSegment every encoding cycle, thus it needs to be
michael@0:    * global in order to store the leftover segments taken from mRawSegment.
michael@0:    */
michael@0:   AudioSegment mSourceSegment;
michael@0: 
michael@0:   /**
michael@0:    * Total samples of delay added by codec, can be queried by the encoder. From
michael@0:    * the perspective of decoding, real data begins this many samples late, so
michael@0:    * the encoder needs to append this many null samples to the end of stream,
michael@0:    * in order to align the time of input and output.
michael@0:    */
michael@0:   int mLookahead;
michael@0: 
michael@0:   /**
michael@0:    * If the input sample rate does not divide 48kHz evenly, the input data are
michael@0:    * resampled.
michael@0:    */
michael@0:   SpeexResamplerState* mResampler;
michael@0: 
michael@0:   /**
michael@0:    * Store the resampled frames that don't fit into an Opus packet duration.
michael@0:    * They will be prepended to the resampled frames next encoding cycle.
michael@0:    */
michael@0:   nsTArray<AudioDataValue> mResampledLeftover;
michael@0: };
michael@0: 
michael@0: }
michael@0: #endif