SVCD Aspect Problem

[mcaver]

Ok, I'm pretty new to this video capture madness, so someone please let me know if I am doing something wrong. I'm getting really frustrated here.

The problem is that no matter how I convert my video captures to SVCD, they always end up stretched horizontally, almost like they're encoded at the wrong aspect ratio. After playing around with the settings I can get it to look right in Windows Media Player, but PowerDVD still has it stretched and -- most importantly -- when I burn it to CD it is still stretched.

Here's the software I'm using:

* Capture: InterVideo's WinDVR
* Editing & Encoding: Womble's MPEG Video Wizard
* Viewing: Windows Media Player & PowerDVD
* Burning: Nero 5
* Players: Initial DVD-9510 & JVC XV-S200

Here's what I'm doing:

I'm using WinDVR to capture video from my tv tuner card at 720x480 @ 29.97 fps and 6800 bit rate. When I look at the resulting .mpeg file, all is well. I know now that the bit rate is major overkill, and the resolution is the only choice I have, but the video plays and looks fine, although it is huge.

I load the .mpeg into MPEG Video Wizard and cut out the commercials. Easy enough. But now I want to encode it as SVCD. So in the Export window, I set the following:

* General->Format: SVCD (MPEG-2 Program)
* Video->Format: MPEG-2
* Video->Resolution: 480x480
* Video->Frame Rate: 29.97
* Video->Expert->PAR: 3:4 (they're all reversed, i.e. 3:4 & 9:16 not of 4:3 & 16:9)
* Video->Bit Rate: VBR 4000 peak (I've tried many different settings)

When encoding finishes the SVCD is stretched horizontally, like I'd tried to encode it at 16:9 or something. VCDs look fine, but SVCDs are stretched/flattened.

A few things I've tried:

* I noticed that the vertical resolution of VCD is 240, which is half of 480, so since they are the right aspect, I encoded a test SVCD sample at exactly double: 704x480 instead of 480x480. The resulting SVCD has perfect aspect ratio, but Nero wouldn't take it because it was non-compliant.

* I encoded a sample with PAR "1.000 (square)" and this fixed the problem, but only in Windows Media Player. PowerDVD and the burned CD both show the same stretched display.

* I encoded a sample at 16:9 (or 9:16 as it says) just to see what happens, and the stretching was even worse, which was expected.

* I downloaded TMPGEnc to see if it has the same issue, but it crashes when I try to open any of my .mpeg captures.

* I downloaded an SVCD sample from this site and it burned fine, no aspect problem (but it looked like a widescreen sample). This makes me think that either MPEG Video Wizard is not encoding it right (or more likely I'm not telling it the right settings), or burning SVCD from a tv capture will always be stretched because it isn't widescreen. But then, I've seen tv captures in SVCD that weren't stretched...

I'm at a loss. I really don't know what else to try. VCDs are just too low quality to settle for, IMO. I'm to the point where I'm running out drive space, so I need to do something soon. I'm considering just dealing with the flat SVCDs. I'd appreciate any help anyone could give. There has to be a solution for this, right?

Thanks,
Michael

[thor300]

Very long post. Sounds like you got a setting wrong, my guess is that it doesnt resize to 480x480 but simple cut out the 480x480 from the center of the 720x480 file. It will then appear stretched and its cut off around 120 pixels on each side.

To open that file in TMPGEnc you would most likely need to frameserve it. Virtualdubmod or dvd2avi or something.

[FOO]

You never told us what the Original aspect ratio was

[mcaver]

Yes, my post was long, but I wanted to be sure I was accurate and thorough to save time. It looks like I wasn't thorough enough, though!

The default aspect ratio for WinDVR is 4:3, which is what I was using. I also have the choice of 16:9 and "Free". Should I use a specific aspect ratio for a specific format, i.e. 4:3 for VCD or 16:9 for SVCD?

[FOO]

I guess the capture from tuner should have defined the ratio as 4:3
Sorry , unecessary question.
I have never used Wombles' encoder do really do anything
SVCD usually looks tall instead of wide.
If Thor is right , you can tell by seeing if the picture is all there (on the sides)
Compare the original with the 480x480
If it's all there on both, then it's probably set to 16:9
Look at both in VdubMod , it ignores the Display Aspect Ratio

[mcaver]

I've compared the original and the SVCD, and there is no cropping around the edge. The SVCD is the full image, it's just stretched horizontally. If I set the DAR to 1.000 when I encode it in Womble, it displays correctly in Windows Media Player, but is still stretched in PowerDVD. I believe WMP uses the DAR and PowerDVD ignores it. So the video really is stretched, but WMP is compensating. Unfortunately, burned CDs do the same as PowerDVD.

On a side note, I found that WinDVR has the ability to record directly into SVCD format. Conversion problems solved, right? Not exactly. I can't for the life of me figure out how to get it to use SVCD when it records. The option is there, but it's greyed out, and no matter what I do it stays greyed out. The help even says "go change this setting", but that setting is greyed out. This isn't a trial version, but the full version that came with my tuner card.

I swear, I can't win for losing. I'm about ready to scrap WinDVR and Womble and try something else. Maybe SnapStream and TMPGEnc.

[RabidDog]

You have won first prize for post of the month.. detailed and thorough.
I think your analysis of the problem sounds correct.. but you dont mention where you want to play this svcd back.. on computer or Dvd player? I would simply encode using 1:1 par as this will probably solve your dilemna. In the end correct playback is more important than the how or why its wrong ..
Trial & error
encode a 5 min clip at par 1:1 4:3 and 16:9, whichever looks best to you, I would stick with. It sounds like a known problem eg pixels on computer are square whereas pixels on tv are oblong 4:3 ergo things which look right on computer look wrong on tv. Good PC dvd player software compensates for this (powerdvd) but not all software correctly interprets svcd's (as opposed to vcd or dvd). Try reading up about what an svcd really is (definition) and the fact that vcd and DVD are more rigourously defined.. especially regarding aspect ratio. At worst change your software?
Also display aspect ratio is different to Pixel aspect ratio

[FOO]

I never got around to trying Womble as a encoder. That might be the problem
i have made trillions of SVCDs but I always used TMPGenc or CCE
with 4:3 material and never noticed a problem.

There was a big confusion at one time as to whether SVCD could
do 16:9 The specs claim it can , but several people that tried it
claimed it doesn't work. The DAR info is in the MPEG2 stream - it
should work. I suspect it's the "some players do and some don't" thing

[mcaver]

Thanks for the responses. I just finished moving, so I haven't been able to hack at this any more lately. I still really want to know why I can't get WinDVR to record directly in SVCD format like it's supposed to and of course, why I can't get the SVCD aspect right. I'm thinking of trying other software than Womble, but I'm not sure what to use. TMPGEnc seems to be the most popular here, but as I mentioned above, if I try to load any of my captured video into it, it crashes. Every time.

RabidDog: Ultimately, I would like to watch these in SVCD format (for quality) in a DVD player. VCD just doesn't cut it. So far, I've been able to get the aspect right for my computer, but not on CD for my DVD players. I've never had a problem playing other people's SVCDs on my DVD players, but I can't seem to get my own right. I can even download samples from here and they burn right. I just can't seem to get it to work for my own, which makes me think they are encoded wrong. Thus I want to try new encoding software, or better yet, just record straight into SVCD. The software I have right now just doesn't seem to cut it. I'm open to other ideas if anyone has them.

[mcaver]

Well, I couldn't load my recorded video in TMPGEnc without it crashing, so I downloaded the free trial of TMPGEnc Plus...and it encodes SVCD perfectly, even on my DVD player! Woohoo! I can finally move forward!