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IcedT
3rd January 2002, 02:46
***originally posted in General Discussion, someone helpfully pointed out that this is a better place for it, hope you're happy xzquala ;) ***

Hi all,

I would like to know how to change/set the aspect ratio of an already encoded mpeg2 stream (unencrypted). Is there some tool that can do that?

I'm using flaskMpeg with the LSX plugin to encode my mpg2's. The thing is that LSX doesn't set any aspect ratio flag or whatever it is, it just takes whatever it gets. In flask you can check 'Keep aspect ratio', in my case the original AR is usually 16:9, but unfortunately in that case it sends the frames with black-bars to compensate for the aspect ratio to LSX which willingly encodes those too. When I uncheck 'Keep Aspect Ratio' in flask, only the actual data gets encoded, but without the aspect ratio data, the player, mostly PowerDVD, obviously doesn't know how to render it correctly.

I usually encode at high quality with AC3. I also use bbmpeg, virtualdub, avisynth, well, the usual stuff, but couldn't find a solution.

Many thanks for your help!

IcedT

[I'm not really concerned with any flask setting.
Rather I'd like to know how to change the aspect ratio of any given Mpeg2 stream. I think that it maybe is just a flag, maybe all over the stream, I don't know. Maybe it isn't possible without lengthy recompile. Generally, it's more a LSX problem than flask related. And I'm not so sure if I qualify for customer support]

IcedT
3rd January 2002, 16:19
Well, I found a solution to my problem: encoding with CCE rather than LSX, boy is that a fast bastard. CCE sets the AR correctly. Then multiplexing with bbmpg, and I'm happy, no letterbox.

I'm still curious if one can change the AR of mpg2's, I have a lot of older projects. Also CCE & bbmpg are quite complicated, my program streams play correctly in PowerDVD, but WMP can't play them normally. It's not overflows - I think, WMP is crap anyway, who cares.

mikeathome
4th January 2002, 11:16
Here's your solution.

http://frankw.mytoday.de/

http://frankw.mytoday.de/DVDPatcher_102a.gif

Tip:
Patch Header only ! Is sufficient in most cases.

The ultimate tool to input 480x576 (non-standard for DVD) as 352x576 into Maestro. After input immediately re-patch the stream, Maestro will work further on with it.

mike

IcedT
4th January 2002, 17:08
Hey that's fantastic. Exactly what I need.

Many thanks!

IcedT
4th January 2002, 17:19
One big caveat though, it's for PAL, but I'm working in NTSC resolution,
and it always wants to patch the resolution info, too.

Any ideas?
I think I'll mail the author.

ultrabrutal
6th January 2002, 16:44
If I follow the links I get to some tv programs...

chilliman
6th January 2002, 17:10
I get to some tv programs too

Methanoid
17th January 2002, 13:41
Originally posted by IcedT
One big caveat though, it's for PAL, but I'm working in NTSC resolution,
and it always wants to patch the resolution info, too.

Any ideas?
I think I'll mail the author.

Try this site and his program. I've been using this for months to correct a problem in MPEG2VCR making the aspect ratio go all screwy.

http://www.geocities.com/eby_vdo/

I'd be interested if this can help people put SVCDs content onto DVDR as I have a few hundred SVCDs I'd rather have on DVDRs when that arrives!

robinsj
18th January 2002, 19:48
I am trying to use this program that you have posted info about... trying to convert the header from svcd to dvd header.. so the .mpg file i load up into it is 480x480 ... when i try and change it.. and click fix it.. and then check the header on the fixed file.. it is still 480x480.. am i doing something wrong??

jason