audiostream.h

/* ScummVM - Graphic Adventure Engine
 *
 * ScummVM is the legal property of its developers, whose names
 * are too numerous to list here. Please refer to the COPYRIGHT
 * file distributed with this source distribution.
 *
 * This program is free software: you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation, either version 3 of the License, or
 * (at your option) any later version.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program.  If not, see <http://www.gnu.org/licenses/>.
 *
 */
 
#ifndef AUDIO_AUDIOSTREAM_H
#define AUDIO_AUDIOSTREAM_H
 
#include "common/ptr.h"
#include "common/scummsys.h"
#include "common/types.h"
 
#include "audio/timestamp.h"
 
namespace Common {
class Path;
class SeekableReadStream;
}
 
namespace Audio {
 
class AudioStream {
public:
    virtual ~AudioStream() {}
 
    virtual int readBuffer(int16 *buffer, const int numSamples) = 0;
 
    virtual bool isStereo() const = 0;
 
    virtual int getRate() const = 0;
 
    virtual bool endOfData() const = 0;
 
    virtual bool endOfStream() const { return endOfData(); }
};
 
class RewindableAudioStream : public virtual AudioStream {
public:
    virtual bool rewind() = 0;
};
 
class LoopableAudioStream : public virtual AudioStream {
public:
 
    virtual uint getCompleteIterations() const = 0;
 
    virtual void setRemainingIterations(uint loops) = 0;
};
 
class LoopingAudioStream : public LoopableAudioStream {
public:
    LoopingAudioStream(RewindableAudioStream *stream, uint loops, DisposeAfterUse::Flag disposeAfterUse = DisposeAfterUse::YES, bool rewind = true);
 
    LoopingAudioStream(Common::DisposablePtr<RewindableAudioStream>&& stream, uint loops, bool rewind = true);
 
    int readBuffer(int16 *buffer, const int numSamples) override;
    bool endOfData() const override;
    bool endOfStream() const override;
 
    bool isStereo() const override { return _parent->isStereo(); }
    int getRate() const override { return _parent->getRate(); }
 
    uint getCompleteIterations() const override { return _completeIterations; }
    void setRemainingIterations(uint loops) override { _loops = _completeIterations + loops; }
private:
    Common::DisposablePtr<RewindableAudioStream> _parent;
 
    uint _loops;
    uint _completeIterations;
};
 
AudioStream *makeLoopingAudioStream(RewindableAudioStream *stream, uint loops);
 
class SeekableAudioStream : public virtual RewindableAudioStream {
public:
    static SeekableAudioStream *openStreamFile(const Common::Path &basename);
 
    bool seek(uint32 where) {
        return seek(Timestamp(where, getRate()));
    }
 
    virtual bool seek(const Timestamp &where) = 0;
 
    virtual Timestamp getLength() const = 0;
 
    bool rewind() override { return seek(0); }
};
 
AudioStream *makeLoopingAudioStream(SeekableAudioStream *stream, Timestamp start, Timestamp end, uint loops);
 
class SubLoopingAudioStream : public LoopableAudioStream {
public:
    SubLoopingAudioStream(SeekableAudioStream *stream, uint loops,
                          const Timestamp loopStart,
                          const Timestamp loopEnd,
                          DisposeAfterUse::Flag disposeAfterUse = DisposeAfterUse::YES);
 
    int readBuffer(int16 *buffer, const int numSamples) override;
    bool endOfData() const override;
    bool endOfStream() const override;
 
    bool isStereo() const override { return _parent->isStereo(); }
    int getRate() const override { return _parent->getRate(); }
 
    uint getCompleteIterations() const override { return _completeIterations; }
    void setRemainingIterations(uint loops) override { _loops = _completeIterations + loops; }
private:
    Common::DisposablePtr<SeekableAudioStream> _parent;
 
    uint _loops;
    uint _completeIterations;
    Timestamp _pos;
    Timestamp _loopStart, _loopEnd;
};
 
 
class SubSeekableAudioStream : public SeekableAudioStream {
public:
    SubSeekableAudioStream(SeekableAudioStream *parent, const Timestamp start, const Timestamp end, DisposeAfterUse::Flag disposeAfterUse = DisposeAfterUse::YES);
 
    int readBuffer(int16 *buffer, const int numSamples) override;
 
    bool isStereo() const override { return _parent->isStereo(); }
 
    int getRate() const override { return _parent->getRate(); }
 
    bool endOfData() const override { return (_pos >= _length) || _parent->endOfData(); }
    bool endOfStream() const override { return (_pos >= _length) || _parent->endOfStream(); }
 
    bool seek(const Timestamp &where) override;
 
    Timestamp getLength() const override { return _length; }
private:
    Common::DisposablePtr<SeekableAudioStream> _parent;
 
    const Timestamp _start;
    const Timestamp _length;
    Timestamp _pos;
};
 
class QueuingAudioStream : public Audio::AudioStream {
public:
 
    virtual void queueAudioStream(Audio::AudioStream *audStream,
                                  DisposeAfterUse::Flag disposeAfterUse = DisposeAfterUse::YES) = 0;
 
    void queueBuffer(byte *data, uint32 size, DisposeAfterUse::Flag disposeAfterUse, byte flags);
 
    virtual void finish() = 0;
 
    virtual uint32 numQueuedStreams() const = 0;
};
 
QueuingAudioStream *makeQueuingAudioStream(int rate, bool stereo);
 
Timestamp convertTimeToStreamPos(const Timestamp &where, int rate, bool isStereo);
 
AudioStream *makeLimitingAudioStream(AudioStream *parentStream, const Timestamp &length, DisposeAfterUse::Flag disposeAfterUse = DisposeAfterUse::YES);
 
class PacketizedAudioStream : public virtual AudioStream {
public:
    virtual ~PacketizedAudioStream() {}
 
    virtual void queuePacket(Common::SeekableReadStream *data) = 0;
 
    virtual void finish() = 0;
};
 
class StatelessPacketizedAudioStream : public PacketizedAudioStream {
public:
    StatelessPacketizedAudioStream(uint rate, uint channels) :
        _rate(rate), _channels(channels), _stream(makeQueuingAudioStream(rate, channels == 2)) {}
    virtual ~StatelessPacketizedAudioStream() {}
 
    // AudioStream API
    bool isStereo() const override { return _channels == 2; }
    int getRate() const override { return _rate; }
    int readBuffer(int16 *data, const int numSamples) override { return _stream->readBuffer(data, numSamples); }
    bool endOfData() const override { return _stream->endOfData(); }
    bool endOfStream() const override { return _stream->endOfStream(); }
 
    uint32 numQueuedStreams() const { return _stream->numQueuedStreams(); }
 
    // PacketizedAudioStream API
    void queuePacket(Common::SeekableReadStream *data) override { _stream->queueAudioStream(makeStream(data)); }
    void finish() override { _stream->finish(); }
 
    uint getChannels() const { return _channels; }
 
protected:
    virtual AudioStream *makeStream(Common::SeekableReadStream *data) = 0;
 
private:
    uint _rate;
    uint _channels;
    Common::ScopedPtr<QueuingAudioStream> _stream;
};
 
AudioStream *makeNullAudioStream();
 
AudioStream *makeSilentAudioStream(int rate, bool stereo);
 
} // End of namespace Audio
 
#endif