interesting XVCD problem

[xed]

Not quite a newbie, having pretty much mastered VCD and SVCD encoding & burning using TMPGenc.
Now time to move on XVCDs. Whoops! Interesting problem.
Here's my procedure: TMPGenc encode from a DV source to MPEG -2 720 x 480 using a nice decent bitrate (say 5 mbits average, 8 max manual VBR) and then use Nero 5.5.x to burn the MPEG-2 file to a CD-R as an SVCD with compliance turned off (since this is not a strictly
legal SVCD -- it has 720 x 480 video rez instead of 480 x 480).
The resulting XVCD plays on my Apex DVD player, all right --
albeit with a strange problem. The video plays, then stutters
slightly while the audio stops for a moment, then the video plays
some more (ad infinitum).
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WHAT THIS PROBLEM ISN'T:
The problem isn't due to an excessive bitrate overloading my poor li'l DVD player, since I have successfully encoded and burnt SVCDs with bitrates of 8 mbits CBR. They play perfectly on my Apex DVD player.
Also, XVCDs with much lower bitrates (as low a 2.5 mbits) exhibit the
same problem. So the issue appears to involve encoding and not the
DVD player or bitrate. Also, playback of encoded XVCD files on my computer using Windows Media Player exhibits exactly the same visual stutter and audio dropout problems. Not so VCD files or SVCD files.
Not using a weird new version of TMPGenc like 7 or 8. I have stuck
with the good old standby 2.56, which seems to be the ultimate perfecto version so far.
The problem cannot be due to corruption of my DV source, since I'm using DV source files captured from the same identical input used to
encode VCDs and SVCDs. VCDs and SVCDs created with TMPGenc from my DV source exhibit zero motion problems and zero audio interrruptions, they play perfectly. XVCDS, no go.
The problem ain't disk fragmentation, since I defrag twixt every encode.
The problem ain't some weird OS like ME since I am using plain-vanilla WIN98SE with FAT-32 (and, yes, ScanDisk confirms that my FATs are peachky-keen 'n uncorrupted).
The problem ain't some some other process runnig simultaneously with TMPGenc. I leave the computer alone whenever it encodes and don't do things like download files or go on line or (what-have-you) while TMPGenc runs.
My setup is a PIII 450 with a Medea VideoRaid and an OS 8 gig hard drive and 128 megs RAM. Okay, not fantastic, but it gets the job done, and reasonably fast with TMPGenc even on SVCD files.
DVD players tested: Daewoo 5700 plays XVCDs with problems noted above. Panasonic (model unknown, can't recall, neighbor's machine) won't play 'em at all. Apex AD1100 plays XVCDs with problems noted above. (The Panasonic is an older model, probably why it crashes & burns.)
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BTW, in my experience (humble as it is) the instructions for burning XVCDs on the www.vcdhelp.com FAQ don't work. Following those instructions produces a CD-R which loads but will not play on any one of 3 different DVD players (mine and 2 neighbors', an Apex, a Daewoo and a Panasonic).
By contrast, burning a XVCD encoded into MPEG-2 at 720 x 480 as an SVCD with compliance turned off WILL play on my Apex and on the neighbor's Daewoo with these video stuttering and audio dropout problems, but _won't_ play on the neighbor's Panasonic at all. (Won't even load.)
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Let the torrent of envenomed verbal abuse begin! Disabuse me of my gross stupidity and allegedly tertiary-syphilis-induced brain damage! What am I doin' wrong to get a problem-free XVCD, kiddies?

[vitualis]

Just to clarify for other respondents, this is an XSVCD (its MPEG-2 burnt as if it were a SVCD right?). Generally, we refer XVCDs as VCDs (MPEG-1 burnt as a VCD) that is non-standard in some regard.

It sounds like an encoder problem... Your MPEGs don't play right on both your PC and stand-alone player?

Regards.

[wkc]

You've mentioned using Windows Media Player exhibits exactly the same visual shutter and audio dropout problems. That has to be something wrong with the encoding process.

If it's just the visual problem, i would have guessed the field order not set as Field B first. But with audio dropout? You got me.

[bugster]

If I understand you correctly, you are producing DVD standard mpeg-2 files and burning as SVCD. You also say SVCD's (480 * 480 ?) with 8 mbits CBR play fine. You also say these problems occur with video encoded using manual VBR and the same symptoms show with Windows Media Player.

My Guess would be that it is Manual VBR that is the problem. Perhaps sudden changes in bitrate cause the decoders problems (especially jumps from low to high bitrate I would expect). Have you tried using Automatic VBR (CQ or 2-pass) to see if it causes the same problems?

I only suggest this as I encode many videos to DVD standard mpeg-2 (and author/burn to DVD-r) using Automatic VBR encoding with TmpGenc and have no such problems.

Just an idea.

Bugster

[puertorican138]

What speed did you burn your CD-R's at?

[vitualis]

If the encoded files as played on the PC show the say problem, it is highly unlikely to be a burning/media compatibility issue.

Regards.

[xed]

Thanks for the responses.

Virtualis: Yes, on reflection you're exactly right -- I was 100% mistaken in saying I'm burning XVCDs. Instead, as you point out, I'm burning XSVCDs...which is to say, I am burning 720 x 480 MPEG-2 video files on CD-R using an SVCD template in Nero, rather than XVCD (which is apparently 720 x 480 MPEG-1 video on CD-R using a VCD template). Thanks for the correction.
AFAIK my XSVCD CD-Rs don't play correctly on both Windows Media Player *and* on 2 different stand-alone DVD players (Daewoo 5700 and Apex AD1100. However, all the other VCDs and SVCDs no matter how high the bitrate play play perfectly on both those standalone DVD players. So I seem to have figured out how to reliably produce problem-free VCDs and SVCDs with TMPGEnc.
Reason I say "AFAIK" is that Windows Media Player doesn't do a real spiffy job of playing ANY DVD-format video. It's pretty choppy & jerky apparently 'cause WMP just isn't nearly as good at playing DVD videos as, say, PowerDVD (which I don't have, alas). WMP does *not* exhibit this choppiness or jerkiness when playing back VCD or SVCD files from disk, incidentally. WMP seems to go to pot only when playing back DVD-format MPEG-2 720 x 480 files.
So it's hard to tell whether the video is really stuttering and jerking in WMP due to an encoding problem, or just the fact that Windows Media Player (apparently) sucks as a DVD player. But that's not surprpisng -- you apparently need specialized software to do a really good job of playing back DVD-format MPEG-2 files in Windows.
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Bugster -- thanks for the suggestion. Will try encoding the MPEG-2 using CQ in TMPGEnc. Your point about sudden changes in bitrates proving problematic for some encoders is a valuable piece of info.
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puertorican138 -- burned 'em at 8x speed on a Plextor 16x burner. This speed doesn't have problems producing perfect SVCDs with 480 x 480 MPEG-2 at 8 mbits, so I'm guessing (!) that the burning speed isn't an issue. BTW, Nero *never* reports any buffers overruns, ever, even when I burn at 16x, and I haven't had any problems with corrupted VCDs or SVCDs due to buffer overruns AFAIK. But thanks for the suggestion, it's a good idea.
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Virtualis -- am I correct in deducing that if I burn SVCDs with an SVCD template but containing MPEG-2 720 x 480 video at a high bitrate I theoretically *ought* to be able to play 'em back on at least some DVD players (like the Daewoo 5700 and the Apex AD1100) without problems?
Or should I abandon the process in favor ox 480 x 480 MPEG-2 SVCDs?

[thxkid]

well I use the capture card WINPVR and capture SVCD's at 704x480 at 5000 bitrate, at CQ, 224 audio at 44,100 burn with NERO 5.5 with SVCD compliant turned off use a HP 9150 burned at 8x, pop it into any of my 3 Daewoo 5800's and they play back perfect, tried as high as 7000 and stills plays back fine, starts to freeze when I get it to 8000, now tried to do the same thing with a AVI captured from same card and encoded with TMPGE 12a using either a SVCD template adjusted to 704x480 at 7000 or even the DVD template with the audio adjusted to 44,100 and I get a slight studder on the video, audio plays back fine, will try again and use field b 1st, but I have no idea why the MPEG2 captured from the WINPVR card plays back perfect and what I encode does not unless its the field choice. But it will work on the daewoo's if you get it right.

[vitualis]

Virtualis -- am I correct in deducing that if I burn SVCDs with an SVCD template but containing MPEG-2 720 x 480 video at a high bitrate I theoretically *ought* to be able to play 'em back on at least some DVD players (like the Daewoo 5700 and the Apex AD1100) without problems?

That is what many people have remarked on this forum. I can't personally say since I don't have either of these players and haven't every actually tried making high framesize XSVCDs...

Regards.