func: static int sox_read_packet(AVFormatContext *s,
  
                             AVPacket *pkt)
  
  {
  
      int ret, size;
  
  
  
      if (url_feof(s->pb))
  
          return AVERROR_EOF;
  
  
  
      size = SOX_SAMPLES*s->streams[0]->codec->block_align;
  
      ret = av_get_packet(s->pb, pkt, size);
  
      if (ret < 0)
  
          return AVERROR(EIO);
  
  
      pkt->stream_index = 0;
  
      pkt->size = ret;
  
  
  
      return 0;
  
  }