[MPlayer-dev-eng] udp/mpeg2-ts streaming

[nsabbi at fastwebnet.it]

>-- Original Message --
>Date: Fri, 21 May 2004 17:38:50 +0100
>To: mplayer-dev-eng at mplayerhq.hu
>Subject: Re: [MPlayer-dev-eng] udp/mpeg2-ts streaming
>From: "Dermot McGahon" <dermot at dspsrv.com>
>Reply-To: mplayer-dev-eng at mplayerhq.hu
>
>
>On Thu, 20 May 2004 16:50:09 +0200, Nico Sabbi <nsabbi at tiscali.it> wrote:
>
>> I suspect that there's something wrong with the management of audio PTSs
> 
>> in this (demux_rtp->demux_ts)
>> configuration.  It should just work, but there may be bugs.
>> I'll look into the code tonight.
>
>Ciao Nico,
>
>Two gdb logs, at:
>
>http://www.bqbsoftware.ie/mplayer_logs/audio_usage/
>
>(1) 2106_audio_usage_gdb
>
>     Trace just confirming that audio_time_usage is high.
>
>(2) 2106_audio_usage_gdb1
>
>     This trace allows 100 video frames to display and
>     then prints out audio_time_usage and sh_video->timer.
>
>
>There is something wrong with the jumps in audio_time_usage.
>
>I will keep tracing but wanted to let you know how far I've
>gotten.
>
>   // Fill buffer if needed:
>   current_module="decode_audio";   // Enter AUDIO decoder module
>   t=GetTimer();
>   while(sh_audio->a_out_buffer_len<playsize && !d_audio->eof){
>     int  
>ret=decode_audio(sh_audio,&sh_audio->a_out_buffer[sh_audio->a_out_buffer_len],
>         playsize-sh_audio->a_out_buffer_len,sh_audio->a_out_buffer_size-sh_audio->a_out_buffer_len);
>     if(ret<=0) break; // EOF?
>     sh_audio->a_out_buffer_len+=ret;
>   }
>   t=GetTimer()-t;
>   tt = t*0.000001f; audio_time_usage+=tt;
>
>
>What could cause decode_audio() to take longer than it
>really should?
>


as far as I can guess there are 2 possibilities:
1) the audio_pts of demuxer_type_demuxers (used when linking 2 demuxers
together) is calculated in a  wrong way
2) I'm buffering too much data in demux_ts (a complete PES), that 
maybe is detrimental  for audio (but on the other side this mechanism 
plays well in the case of a file, hmmm)

>Why is 't' multiplied by 0.000001f?
>

looks like 1 microsecond precision


>
>Dermot.
>--
>

I installed vls and stream the file to rtp://127.0.0.1:5001, then used
mplayer without Live libraries, and as I expected everything played well.

I will investigate more this week-end and I'll keep you informed.

Nico