Vlc - problems

[Samuel Hocevar]

On Tue, Jul 18, 2000, Gustavo Homem wrote:

> To begin, thank you very much for the fast answer. About what you
> think is a X11 problem, well, it doesn't happen with xmovie. Xmovie
> is also VERY slow, but doesn't lock the system at all.

   I'll have a look at XMovie and see how they handle the X11 flushing.
Perhaps we are doing something wrong.

> It is as slow as vlc but unfortunately xmovie doesn't read from stdin
> so it is not pratical, you know why...

   Of course :)

>  I will now be more precise about my system:
> 
> AMD K7 ATHLON 550 mhz
> 128 Mb Ram
> Ati Rage 128 16 Mb 
> XFree 3.3.6 with SVGA server
> Color depth= 32bpp
> Resolution=1024x768

> The rpm I tried was the 0.1.99c (the latest rpm available )and the gz
> I tried was 0.1.99d, wich is the one also available in freshmeat.org .
> The second has a default smaller window , so I saw they were different
> versions, but one works(slowly, and blocks the system) and the other
> can't do better than the pink shadows (but doesn't block the system).

   Okay. This probably means I fscked something up with the MMX YUV
plugin for 32 bpp. I'll have a look at it tonight.

> The c key produces this on stdin: (and makes no difference in the image):
> yuvmmx error: unhandled function, grayscale, bpp = 32è

   There is no MMX display for grayscale 32 bpp. To use plain C display,
you will have to delete the plugin lib/yuvmmx.so before running the vlc.
There will eventually be a way to auto detect plugins and select them in
a more convenient way, but our API hasn't been decided yet.

   You might also want to try the vlc in 16 bpp. It should run quite faster.

> I would like to know if the slowness is due to unused hardware capabilities,
> or to the fact that the player is not card specific.

   It's due to both, actually : we don't use Athlon capabilities to the
max, and we don't use the card's graphic features (mainly beacause we
don't know how to do it).

> In Mswindows the movie runs FAST in Full Screen, but I have a ATI
> player.

   The player is fast under windows for two reasons : first, the ATI
card has special features for MPEG decoding (though I'm not sure about
this one), and second, the card can display and scale the decoded image
using no CPU power at all, thus gaining about 30%-40% in speed.

> Anyway, maybe others don't have this slowness problem, in that case I
> need to know what is wrong with my system, otherwyse the problem must
> be corrected because we must be able to see the movie in normal movie
> speed. Can you play a .vob decently in a not too small window?

   Yes, it runs surprisingly well on my machine, but mostly because I
have a Matrox G200 which is pretty well supported under X.

> I would like to say that I really aprecciate your effort in bringing
> DVD playing to Linux,

   Thanks. We appreciate feedback from users even more :)

> it is the only barrier that disables me (and many people)to wipe my
> MsWindows from the Hd. I would like to help in something if I could,
> I'm not a DVD expert but I can code alright. So after a few days I
> will start hacking something.

   The project might seem a bit "closed" because all developers are from
the same school, but actually everyone is welcome to contribute code or
ideas or whatever. If at any time you think you need a CVS access, just
tell us.

   For now, what needs to be done is :
 - various optimizations in the whole decoding process
 - MMX support
 - improving the GUIs (playlist, open file, ...)
 - plugins API
 - DVD navigation features
 - MPEG 1 support

   I'd also love to see support for open formats such as Vorbis Ogg,
accelerated display for various hardware, and even a win32 port.

   If you have other ideas about what could be done, or if you want to
help on a particular topic, we could meet on Irc (irc.openprojects.net,
channel #videolan). Also note that there is another Linux DVD project
going pretty well on www.linuxvideo.org, they have interesting stuff as
well, and they player is often faster than ours (for now :). They're
also on irc, hiding on #livid.

Regards,
Sam.
-- 
Samuel Hocevar <sam at via.ecp.fr> - http://www.via.ecp.fr/~sam/
     Do not try and fight the Cabal. That's impossible.
  Instead only try to realize the truth. There is no Cabal.