Jerky playback

[Chris Jensen]

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.

> 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).

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 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