LiveSound.h

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// LiveSound.h: - base class for embedded sound handling, for gnash
// 
//   Copyright (C) 2005, 2006, 2007, 2008, 2009, 2010, 2011, 2012
//   Free Software Foundation, Inc
// 
// 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, write to the Free Software
// Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA

#ifndef SOUND_LIVESOUND_H
#define SOUND_LIVESOUND_H

#include <boost/scoped_ptr.hpp>
#include <cassert>
#include <boost/cstdint.hpp> // For C99 int types

#include "InputStream.h" 
#include "AudioDecoder.h" 
#include "SimpleBuffer.h" 
#include "SoundInfo.h"

// Forward declarations
namespace gnash {
    namespace media {
        class MediaHandler;
    }
}

namespace gnash {
namespace sound {

//
class LiveSound : public InputStream
{
protected:

    //
    LiveSound(media::MediaHandler& mh, const media::SoundInfo& info,
            size_t inPoint);

    // Pointer handling and checking functions
    const boost::int16_t* getDecodedData(unsigned long int pos) const {
        assert(pos < _decodedData.size());
        return reinterpret_cast<const boost::int16_t*>(
                _decodedData.data() + pos);
    }

    //
    virtual bool moreData() = 0;

    //
    virtual bool eof() const = 0;

    void restart() {
        _playbackPosition = _inPoint;
        _samplesFetched = 0;
    }

    //
    unsigned int samplesFetched() const {
        return _samplesFetched;
    }

    size_t playbackPosition() const {
        return _playbackPosition;
    }

    media::AudioDecoder& decoder() const {
        return *_decoder;
    }

    void appendDecodedData(boost::uint8_t* data, unsigned int size) {
        _decodedData.append(data, size);
        delete [] data;
    }

    unsigned int decodedSamplesAhead() const {

        const unsigned int dds = _decodedData.size();
        if (dds <= _playbackPosition) return 0; 

        size_t bytesAhead = dds - _playbackPosition;
        bytesAhead = checkEarlierEnd(bytesAhead, _playbackPosition);

        assert(!(bytesAhead % 2));

        const unsigned int samplesAhead = bytesAhead / 2;
        return samplesAhead;
    }

private:

    //
    virtual size_t checkEarlierEnd(size_t left, size_t) const {
        return left;
    }

    // See dox in sound_handler.h (InputStream)
    unsigned int fetchSamples(boost::int16_t* to, unsigned int nSamples);

    void createDecoder(media::MediaHandler& mediaHandler,
            const media::SoundInfo& info);

    virtual bool decodingCompleted() const = 0;

    const size_t _inPoint;

    size_t _playbackPosition;

    unsigned long _samplesFetched;

    boost::scoped_ptr<media::AudioDecoder> _decoder;

    SimpleBuffer _decodedData;

};


} // gnash.sound namespace 
} // namespace gnash

#endif // SOUND_EMBEDSOUNDINST_H