[MPlayer-dev-eng] audio pts bad in mplayer if audio encoding with lavc (mencoder)

[Ötvös Attila]

Hi All!

My problem incorrect apts if I play with mplayer encoded avi:
mencoder in.avi -ovc lavc -oac lavc -o out.avi
mplayer out.avi -> apts=correct pts * audio block len

Relevant files ----------:
libmpcodecs/ae_lavc:
static int bind_lavc(audio_encoder_t *encoder, muxer_stream_t *mux_a)
line 50:
	if(lavc_actx->block_align)
		mux_a->h.dwSampleSize = mux_a->h.dwScale = lavc_actx->block_align;
	else 
	{
		mux_a->h.dwScale = (mux_a->wf->nAvgBytesPerSec * lavc_actx->frame_size)/ 
mux_a->wf->nSamplesPerSec; /* for cbr */
	
		if ((mux_a->wf->nAvgBytesPerSec *
			lavc_actx->frame_size) % mux_a->wf->nSamplesPerSec) 
		{
			mux_a->h.dwScale = lavc_actx->frame_size;
			mux_a->h.dwRate = lavc_actx->sample_rate;
			mux_a->h.dwSampleSize = 0; // Blocksize not constant
		} 
		else 
			mux_a->h.dwSampleSize = 0;
	}
        if(mux_a->h.dwSampleSize)
                mux_a->wf->nBlockAlign = mux_a->h.dwSampleSize;
        else
                mux_a->wf->nBlockAlign = 1;

libmpdemux/demux_avi:
demux_stream_t* demux_avi_select_stream(demuxer_t *demux,unsigned int id)
line 45:
	if(sh->wf){
	  priv->audio_block_size=sh->wf->nBlockAlign;

libmpdemux/demux_avi:
static int demux_avi_read_packet(demuxer_t *demux,demux_stream_t *ds,unsigned 
int id,unsigned int len,int idxpos,int flags)
line 125:
      if(pts_from_bps){
	  pts = priv->audio_block_no *
	    (float)((sh_audio_t*)demux->audio->sh)->audio.dwScale /
	    (float)((sh_audio_t*)demux->audio->sh)->audio.dwRate;
      } else
          pts=priv->avi_audio_pts; //+priv->pts_correction;
      priv->avi_audio_pts=0;
      // update blockcount:
      priv->audio_block_no+=priv->audio_block_size ?
	((len+priv->audio_block_size-1)/priv->audio_block_size) : 1;

end of relevant files --------

mencoder:
nBlockAlign always 1 if lavc_actx->block_align is 0

mplayer:
priv->audio_block_no+=(packet len) if nBlockAlign is 1 -->
pts=(byte pos)*dwScale/dwRate if nBlockAlign is 1

I think so correct apts:
nBlockAlign=dwScale in mencoder (ae_lavc) or
swScale=1 if nBlockAlign is 1 in mplayer (demux_avi)

Comment or other solving?

Best regards.
Attila
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