[MPlayer-users] Problems playing DVB-T HD streams

[Carl Eugen Hoyos]

Etienne Sandré-Chardonnal <etienne.sandre <at> polytechnique.org> writes:

> I have trouble to play some DVB-T channels with mplayers.
> 
> Description of the problem:
> 
> - I am living in Paris, France. I have an AverMedia Volar Black HD USB
> tuner. My channels.conf is set up properly : everything plays fine with vlc.
> Mplayer works for all SD channels, and one HD channel (ARTE).

Since this is an old thread, I repeat:
ARTE is not using PAFF for H264, most other HD programs are, and PAFF can only
be played with (either) -demuxer mpegts -mc 1 (works always), or -demuxer lavf
-nocorrect-pts (works sometimes, needs -mc 1 sometimes)
-mc 1 always also needs delay (the value is between -0.1 and -0.5 and depends on
the stream).
Increasing fps never helps.

> The three
> other channels (TF1, M6, F2) are very bad : slow playback, lots of bad
> blocks, freezes. The main differences with the working HD channel ARTE are :
> separate multiplex, VBR instead of CBR, DD+ (E-AC3) sound instead of MP2
> sound.
> 
> - I am under debian unstable on AMD64, kernel 2.6.29, up to date. The
> mplayer package provides a mplayer version : dev-SVN-r29417. I also tried to
> compile the latest mplayer source image, with same results. I have tried
> various -vo : xv,x11,vdpau. I have tried vc: ffh264,ffh264vdpau. All with
> same results.
> 
> - I have tried to dump the stream to a ts file. The file plays not too bad
> with mplayer, but slow (about 1/2) and jerky, while the CPU is not
> overloaded (25\%, ie half of a single core). The file plays smoothly with
> VLC. Using -fps 50 does not accelerate or improve the playback. You may
> download the ts file at : http://www.galinette.org/test.ts

Sorry, I have several problems with your bug report:
vlc fails to play audio with your sample (for me).
Do you mention anywhere that audio (also) does not play with mplayer?
If it does not play, how do you know video is too slow?

However:
You need this patch for audio to play:
http://thread.gmane.org/gmane.comp.video.ffmpeg.devel/90875/focus=98581
(I do not know if it still applies cleanly, but I use it successfully with your
sample, so your efforts are not futile)
A/V sync is nearly constant with
mplayer -mc 1 test.ts -ac -a52, -demuxer lavf -nocorrect-pts
mplayer -mc 1 test.ts -ac -a52, -demuxer mpegts
(ac a52 does not work with E-AC3)
As already explained, both variants will introduce a small audio delay that you
can fix with either "+"/"-" or -delay -0.2 (or similar).

You may need -cache 10000 to play directly from dvb (I prefer to record). VDPAU
should work fine and allows de-interlacing (if you don't have the slowest card -
Geforce 8400GS).

Thank you for the useful sample, I originally missed it, Carl Eugen