[linux-dvb] Re: mplayer DVB speed II.

[Nico <nsabbi@tiscali.it>]

did you run
mplayer -cache 4096 dvb://

as I previously suggested? Does it help?


Radovan Garabik wrote:

> Following up to my  previous mail about mplayer's slow decoding,
> here are some additional tests:
>
> first, speed of audio decoding (mp2 stream, taken from
> dvb broadcast and saved to hdd as an elementary stream),
> number is CPU usage:
> mpg123    5%
> mpg321   13%
> madplay   9.5%
>
> second, CPU usage of mplayer -vc null:
> -ac mp3    17%
> -ac ffmp2  19%
> -ac null   12%
>
> Further looking into sources revealed that mplayer uses mp123 library
> for audio decoding (so the fastest one), in xine this code is
> unmaintained and does no longer compile, xine uses libmad instead.
> Unfortunately I did not find the way to shut down decoding engine in
> xine, so I cannot make direct comparision (but xine certainly 
> plays the tv more smoothly).
>
> Interesting is the last line, with mplayer -ac null -vc null
> 12% of CPU usage seems to indicate that mplayer spends this time
> only on demuxing, which is quite a loit, since
> ts_es_demux /dev/dvb/adapter0/dvr0 /dev/null /dev/null
> takes only about 2.3%, and
> ts_es_demux /dev/dvb/adapter0/dvr0 file1 file2
> about 6%
>  
12% from the file?
The TS demuxer reassembles packets until the completion of a full PES 
(which may be very big)
but doesn't use temporary buffers, so it shouldn't be so slow; besides 
it parses tables (if present),
which ts_es_demux doesn't do.
Can you run the same test on a dump without tables and see if  mplayer 
is faster, please?

> for reference, all the test were done on Canale 5 (Hotbird),
> PII Celeron 266 MHz, Skystar2 rev. 2.6B
>
> Additional, non related note:
> I also tried to save the whole transport stream 
> (with dvbstream -f ... 8192 -o >file.ts), the result was terrible,
> extracted video streams were unwatchable (full of errors).
> Later experiments revealed that I can save about 2 high resolution
> streams, or about 4 lower resolution ones before errors start to be
> too grave. Perhaps it has to do something with PCI bandwidth
> (saving it not into local HDD, but through a PCI network card 
> roughly halved the upper limit for bandwidth that is possible to
> save before errors show up)
>
> Merry Christmas and Happy New Year :-)
do you mean that your card is unable to keep the rate or that only 
mplayer can't play
the full TS stream without corruptions (and that xine can) ?

If so, please post a short sample of that TS to 
ftp://www.mplayerhq.hu/MPlayer/incoming and tell me the name, please.


Nico

>  



--
Info:
To unsubscribe send a mail to ecartis@linuxtv.org with "unsubscribe linux-dvb" as subject.