Jerky playback

[Jean-Paul Saman]

> Hi,
> I should probably make a few things clear. I'm not using a distro, I
> compiled everything on the system myself (sort of following
> www.linuxfromscratch.org). I'm running kernel 2.4.6, xfree 4.1.0 with the
> nvidia driver (v1.0-1251) for a Riva TNT M64 w/ tv out.
> I'm using glibc 2.2.3 and gcc 2.95.3.
> 
> > vlc does not use hardware acceleration for mpeg streams. This has
> > nothing to do with your video output to the screen. Does your graphics
> > card use hardware acceleration?
> 
> Do you mean hardware acceleration for decoding mpeg or displaying? I'm
> certain it can for the later (although I have yet to get xvideo working),
> and I would assume the former also since using --overlay did improve
> performance slightly.
I mean vlc does use acceleration for displaying NOT for mpeg2.

> > On the other hand it looks like you are missing one vital other library,
> like
> > svgalib (I use svgalib-1.4.1-13.i386.rpm) or another. I can't remember
> exactly
> > which libraries you need.
> 
> I'd say this is definately the problem as I had no idea i had to install it.
> Will I need to recompile vlc or anything else to take advantage of svgalib
> once it's installed? (ie xfree, or the xvideo component?)
> Where can I find out what other libraries I need (since I have probably not
> installed them).
At least install development libraries for XFree. My hint at svgalib is
inaccurate you only need it for other output support and can do nicely
without it.

> 
> This is the main problem I seem to be having with vlc is that it's hard to
> understand what software requirements it has, and how to configure it to
> make best use of the software and hardware present. It would be really good
> if these sorts of things could be obviously documented (i realise with all
> the development that there's little time for docs, but even if some of these
> answers could be thrown into the faq it would be a great start.)
> 
> >
> > Are you running a RH 7.x system? If so then recompiling vlc for your
> > machine will solve a lot or all of your troubles now. In RH7.x redhat
> > delivers compiler gcc-2.96 that is not compatible with other gcc
> > compilers. I noticed problems of this kind with vlc and recompilation
> > solved all me problems with vlc. The only thing is you need to find all
> > the libraries that are needed for compilation more or less by trial and
> > error.
I was wondering, because it sounded a lot like problems I had with vlc
for RH7.1 at first. But you explained at the top of the mail 

> I have always been compiling vlc from source, several times now, using
> version 0.2.8 and snapshots from 7/7/01 and 10/7/01, using different compile
> options (BTW the cvs snapshots fail to compile when alsa is enabled, I'll
> post the error tomorrow when I give it another go)
> 
> > If your sound is in MPEG2, then --spdiff will not help you.
> > vlc --help says '--spdif AC3 pass-through mode' and that is a sound
> > stream already decoded as far as I know.
> Because it said "pass through" I thought maybe it would be passing the
> stream to hardware to decode if available. Hmmm, the more i think about that
> assumption the more naive and simple it sounds!
> 
> Thanks again for you're help
> Chris Jensen
Good luck,
Jean-Paul Saman