trouble analysis

[Tom]

playback is still not perfect with 2.80 and I've tried to analyse the
problems.

one, vlc should automatically disable (or offer an option to do so,
enabled by default) the screensaver. the screen going blank is a major
annoyance when it's on a 3x2 m screen and the machine is in the next
room.

two, sound playback is problematic for me. there's some scratching, but
it's only minor and very occasionaly. I haven't yet found any hints on
what might cause it.
however, the most serious problem is that sound is delayed. sound seems
to be about half a second or so behind picture. it's not that it's
being played slower - the delay is constant over time, at least over
the half hour I've tested. right from the start, sound is later than
the picture.
this is on an athlon machine with an es1371 soundcard, using dsp output
because for some reason alsa does not work. a typical line from vmstat
says:

r b w   swpd   free   buff  cache  si  so    bi   bo   in   cs  us  sy
2 0 0  21992   1732 188256   7808  0    0  1024    0  256  577  25   0

I will be testing esd output and report on any changes.


three, vlc has serious performance troubles when anything else is
running. this is NOT due to cpu - I'm running at 75% idle here. but
it's memory related. most swapping activity will kill vlc, causing it to
skip frames. maybe you should include some buffering so it survives a
second or so without input.

four, vlc leaves a small black border around the picture. in windowed
mode, that's no problem. in fullscreen, however, it's noticeable.



all in all, this is an impressive program. it has everything needed to
play DVDs and it's very performant - 25% of a 1200 athlon, so it should
offer good playback on anything above a 350 or so. I'm not sure if the
windos players are capable of that, from my limited experience with
them, I'd guess no.
most importantly, however, vlc is very, very user-friendly. it will
start the movie and be done with it instead of ruining the experience
with region crap, unskippable ads and other bullshit the CSS license
forces on the "authorized" players.

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