dtsdecoder.h

Linux下比较早的基于命令行的DVD播放器

//
// Copyright (c) 2004 by Istv醤 V醨adi
//
// This file is part of dxr3Player, a DVD player written specifically 
// for the DXR3 (aka Hollywood+) decoder card.

// 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 2 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., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA

#ifndef DXR3PLAYER_OUTPUT_DTSDECODER_H
#define DXR3PLAYER_OUTPUT_DTSDECODER_H
//------------------------------------------------------------------------------

#include "AudioDecoder.h"

//------------------------------------------------------------------------------

namespace output {

//------------------------------------------------------------------------------

/**
 * DTS Decoder. It actually does not decode DTS frames, only
 * encapsulates them for HW decoding.
 */
class DTSDecoder : public AudioDecoder
{
private:
    /**
     * The size of the frame buffer. A DTS frame may be at most this
     * many bytes (including synchronization info).
     */
    static const size_t maxFrameSize = 8192;

    /**
     * Frame buffer.
     */
    unsigned char frameBuffer[maxFrameSize];

    /**
     * The offset into the frame being decoded.
     */
    size_t frameOffset;

    /**
     * The length of the current frame being decoded.
     */
    size_t frameLength;

    /**
     * The number of samples in the DTS frame.
     */
    size_t numberOfSamples;

public:
    /**
     * Construct the DTS decoder.
     */
    DTSDecoder(AudioProcessor* audioProcessor);

    /**
     * Reset the decoder.
     */
    virtual void reset();

    /**
     * @see AudioDecoder::decodePacket
     */
    virtual void decodePacket(const unsigned char* data,
                              size_t length, pts_t packetPTS);

private:
    /**
     * Decode the given data.
     *
     * @return if a frame has been completed
     */
    bool decode(const unsigned char*& data, 
                const unsigned char* end);

   /**
     * Copy the data from the given address into the frame buffer,
     * until the given target offset is reached.
     */
    void copy(const unsigned char*& data,
              const unsigned char* end,
              size_t targetOffset);

    /**
     * Determine if the decoder is empty.
     */
    bool isEmpty() const;

    /**
     * Prepare the current frame for HW decoding.
     */
    void prepareFrameForHardwareDecoding();
};

//------------------------------------------------------------------------------

} /* namespace output */

//------------------------------------------------------------------------------
#endif // DXR3PLAYER_OUTPUT_DTSDECODER_H

// Local variables:
// mode: c++
// End: