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SimonSez07
10th December 2001, 03:03
i have been creating SVCD's using the following process:

SmartRipper 2.40
DVD2AVI 1.76 (Decode Audio to WAV file)
AVISynth (using MPEG2DEC Plugin)
- resize/crop
- letterbox
CCE 2.50 (Encode Video using MultiPass VBR)
PULLDOWN.EXE
Panasonic MPEG1 Stand-Alone Encoder v2.51 (Encode Audio to MP2)
bbMPEG v1.24.18 (Multiplex Audio/Video)

when i use this process to create standard 480x480 SVCD's everything goes smoothly, but when i do fullscreen/pan&scan movies, i often want to create non-standard 352x240 SVCD's (i do this to avoid having to use more than two cd's to attain decent image quality, and i find this superior to creating VCD's at the same resolution because of the obvious advantages in MPEG2 and VBR). when i use this method to create MPEG2 files at that resolution with CCE, i get screwed up video streams right out of the encoder before even muxing or burning. i know the avs file i fed into the encoder was clearly 352x240, but powerdvd seems to think the resulting mpeg2 files are 352 x 288, and plays the video with a bar of black (or often screwed up colors) at the bottom. sasami2k cannot play it correctly either. it screws the size up even worse. after burning (w/ nero 5.540), my JVC standalone dvd player plays it fullscreen w/ no bars or distorted stretch, but the image is a little vertically shaky.

any ideas what could be wrong? is some mpeg program stream information recorded incorectly or something??

any help would be appreciated.

thanks,
simon

denfert
10th December 2001, 15:10
MPEG2 is not design to achieve good picture quality in 240 or 288 vetical resolution.

you must use 480 or 576 for pal.
but you may try 352x480.

Antonio S.
10th December 2001, 22:41
You can use this resolutions 720 x 480
480 x 480 (SVCD standard)
or 352 x 480

This is for NSTC...:)

SimonSez07
12th December 2001, 23:01
so ... ur saying that my problems are due to using mpeg2, and not the fault of the framserve process, encoder, or player?? i find it hard to believe that mpeg2 just doesnt like 240 verticle res?? that would seem kind of silly, if the mpeg2 standard was truly limited to 2 choices of verticle resolution.

Has anyone else had any success w/ 352 x 240 or any other non-standard resolution w/ mpeg2??

thanks for ur replies.
- simon

ulfschack
13th December 2001, 14:25
Yes, I have.

For PAL, 352 x 288 and 512 x 384 is some of the out-of-spec resolutions I've succeded with. The former in an attempt to fit an entire james bond movie on one cd, and the latter by plain forgetting to resize in my avs script after divx encoding my home DV.

Forget the comments of what mpeg2 is designed for, that's obviously not really true. Some encoders will have problems if x and y res aren't divisible by 8, though. A whole different matter is the SVCD spec. If you want absolute certainty that your (and every other scvd-able) stand-alone is gonna play it, stick to it.

I see you're an NTSC user and maybe there is a switch you've forgotten somewhere in your encoder telling it so. Or maybe it's the player that got it wrong. What does TmpgEnc, BBmpeg or Bitviewer say about the encoded result ... just load it up and see. Otherwise I don't see anything wrong in your approch.

cheers

sonni_kuba
17th December 2001, 01:17
It is indeed possible to encode at 352x240 with MPEG2

If you are interested, I point you in the direction of the thread (SVCD with VCD resolution).

http://rilanparty.com/vbb/showthread.php?s=&threadid=10166

In short, I have tried it and the results are very impressive. If you are willing to compromise, sound quality (ie. 96kb/s), and have the time to go through two-pass VBR encoding, then you can fit a whole 130 min movie onto 1 80 min CD.

The trick is to encode everything with SVCD specs, ONLY changing the resolution. As Mozart had pointed out, this hacked MPEG2 video is called CVCD. In addition, not all stand-alones will play it. So best to try it out on a CD-RW first.

adam
17th December 2001, 21:08
But CVCD is basically just another term for xvcd or xsvcd, depending on whether you use mpeg1 or mpeg2. Its still conforms to no standard and can't be guaranteed to play on all dvd players, though it does work on most.

SimonSez07: I don't know what to tell you. Mpeg2 and 352x240 res gives me no problems.