www.pudn.com > mediator15src.zip > ac3audio.h

/* 
 * ac3audio.h 
 * Copyright (C) 2001 Arno Hornberger  
 * 
 * This file is part of MPEG Mediator, a free MPEG stream converter. 
 * 
 * MPEG Mediator 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. 
 * 
 * MPEG Mediator 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 AC3AUDIO_H 
#define AC3AUDIO_H 
 
#include "asyncstream.h" 
#include "unpacketizer.h" 
#include "audio.h" 
 
extern "C" 
{ 
#include "config.h" 
#include "a52.h" 
} 
 
class AC3Audio : public Audio 
{ 
  private: 
    enum { FRAMEBUFFERSIZE = 4096 }; 
 
    Unpacketizer *up; 
    int stream_id; 
 
    int payload_size; 
    int payload_pos; 
 
    bool audio_seek; 
 
    __int64 last_pts;           // packet level 
    bool last_pts_used; 
    __int64 current_pts;        // packet level 
    bool current_pts_used; 
 
    __int64 extrapolated_pts;   // frame level 
    bool extrapolated_pts_valid; 
 
    __int64 frame_pts; 
    int frame_samples; 
 
    a52_state_t *state; 
    int sample_rate; 
 
    int bitstream_flags; 
 
    unsigned char *frame_buffer; 
    short Convert(int i); 
 
    void SearchPacket(); 
    unsigned char GetByte(); 
    void GetBytes(unsigned char *dest, int count); 
 
  public: 
    AC3Audio(); 
    ~AC3Audio(); 
 
    void SetInput(AsyncStream *as, int stream_id); 
    void GetFrame(short *sample_buffer); 
    __int64 Tell() { return up->Tell(); } 
 
    __int64 GetPTS() { return frame_pts; } 
    int GetSamplingFrequency() { return sample_rate; } 
    bool IsStereo() { return true; } 
    int GetSampleCount() { return frame_samples; } 
 
    void GetChannelDescriptor(char *desc); 
}; 
 
inline short AC3Audio::Convert(int i) 
{ 
  if (i > 0x43c07fff) 
    return 32767; 
  else if (i < 0x43bf8000) 
    return -32768; 
  else 
    return i - 0x43c00000; 
} 
 
#endif