glitches, another story *g*

[Thomas Jagoditsch <t.ja@gmx.at>]

hi all.

after switching to a bx-board with an old ´350 and 128megs of ram
(yeah, its a bit "overdressed", but the parts were there anyway
except the casing and the memory [they got the 128 only, no 64
*grrr*]) i´ve got error-free recording without any problems and no
syslog-messages, hoooray ;-)

but (there allways seem to be a "but") i have to report another
strange thing.

playing around with the machine on the weekend i recorded the
qualifying of the motorbike-gp on eurosport while watching it.
at the commercials i made a switch to the syslog-console (found a
riva-tnt with video-out which works per default on the tv when there
is no vga-screen connected) to look for recording errors. there were
none.

trying to playback of some interesting scenes i discovered that in
playback-mode the recording sometimes lost a couple of frames (the
bikes were REAL FAST this moments *g*), then lost audio for a couple
of sedonds to minutes with good picture, again good audio with lost
frames and so on.

checking the syslog showed no errors so i became curious.

playing back the same scene a couple of times showed that losing
frames or audio _didnt_ happen the same time every playback.
some runs i´ve got perfect audio, next run no audio at all (beside
the in-sync glitches that every playback has) - this leads to the
conclusion that the recording itself is ok (am i right ?!?) but
playback has problems.

trying to crosscheck on other channels showed no problems at all.
recording the end of "men in black" on pro7 yesterday and playback of
this 20-minute recording behave correctly with no glitches at all.

technical questions:

PAL/NTSC etc.:
my first (now thrown-out) thought was about the possible source of
the video-signal. the gp happend in brasil, so maybe (the picture
showes real bad colors and sharpness) they´re using ntsc to record
and there is a kind of convert-process involved that could cause
problems for the dvb.
recording of other events or even commercials on eurosport showed the
same misbehaving, so this is out.
but, basicly, what about pal, ntsc ... is this important in the "new
digital satellite world" ?

recordings/files:
is there any (non-programmer) way to find out more about the
properties/specialities of the distict recordings, to help debuging
the cause ? are there different sub-formats or are they identic
despite the data ?
could i convert the recording to a mpg-file suitable to play on a
windoze-machines media-player to cross-check the recording itself ?

a lot of questions, i know *g*
btw: links to basics are welcome, too.

wbr.tja...