Problem with aspect ratio

[sagar.n]

I have converted a 16:9 movie into divx. But the problem is i have unknowingly streched the movie to fit fullscreen. Is there any solution to simply change the aspect ratio of movie file without having to reencode the entire movie?

[jggimi]

Either use a player that can resize .avi to 4:3 or 16:9 on-the-fly, such as BSPlayer ... use a container format that supports anamorphic resizing (.mp4, .mkv) ... or re-encode.

[DARcode]

Originally posted by jggimi
Either use a player that can resize .avi to 4:3 or 16:9 on-the-fly, such as BSPlayer ... use a container format that supports anamorphic resizing (.mp4, .mkv) ... or re-encode. Interesting, could you please explain to this poor newbie who uses mp4UI how to modify an MP4 container to obtain that or point me to the right forum FAQ? Thank you.

[jggimi]

See Q10 in the MP4 FAQ (http://forum.doom9.org/showthread.php?s=&threadid=62723).

The tool many use (but I haven't used myself) is called MPEG Mediator. SeeMoreDigital keeps a link (http://seemoredigital.net/05_How_to..._Files/MPEG_Mediator_1.5.html) in his signature.

[DARcode]

Originally posted by jggimi
See Q10 in the MP4 FAQ (http://forum.doom9.org/showthread.php?s=&threadid=62723).

The tool many use (but I haven't used myself) is called MPEG Mediator. SeeMoreDigital keeps a link (http://seemoredigital.net/05_How_to..._Files/MPEG_Mediator_1.5.html) in his signature. Thank you for your suggestions, but neither the MP4 FAQ nor the SeeMoredigital.net website actually tell you how to do it, or am I dense and can't spot it?

[SeeMoreDigital]

Originally posted by DARcode
Thank you for your suggestions, but neither the MP4 FAQ nor the SeeMoredigital.net website actually tell you how to do it, or am I dense and can't spot it? Actually, if you want to add a PAR or DAR signalling to an Mpeg4 in .AVI stream, you need to use MPEG4 Modifier (http://forum.doom9.org/showthread.php?s=&threadid=78050).

And, as jggimi pointed out, you will also need to install a software player that can automatically detect PAR/DAR signalling, such as VLC player. Or install an suitable Mpeg4 direct-show filter. Such as the ones that come with XviD 1.1 builds or Nero Vision Express (incorporating Nero Recode2 and ShowTime Player).


Cheers

[DARcode]

Originally posted by SeeMoreDigital
Actually, if you want to add a PAR or DAR signalling to an Mpeg4 in .AVI stream, you need to use MPEG4 Modifier (http://forum.doom9.org/showthread.php?s=&threadid=78050).

And, as jggimi pointed out, you will also need to install a software player that can automatically detect PAR/DAR signalling, such as VLC player. Or install an suitable Mpeg4 direct-show filter. Such as the ones that come with XviD 1.1 builds or Nero Vision Express (incorporating Nero Recode2 and ShowTime Player).


Cheers Thank you, I've been able to get it done with MPEG4 Modifier, but how can I do the same for the MP4 container?

Also, pardon my noobness, how should PAR and DAR interact?
I mean, if I have for example an XviD which is claerly distorted like 16.9 getting played like a 4:3, should I consider the original PAR value in setting an adjusted DAR one?

[SeeMoreDigital]

Originally posted by DARcode
Thank you, I've been able to get it done with MPEG4 Modifier, but how can I do the same for the MP4 container? There's a "command-line" tool called ARchange that can do this. For more information please refer to this thread: -

http://forum.doom9.org/showthread.php?s=&threadid=86870

Originally posted by DARcode
Also, pardon my noobness, how should PAR and DAR interact?
I mean, if I have for example an XviD which is claerly distorted like 16.9 getting played like a 4:3, should I consider the original PAR value in setting an adjusted DAR one? The whole PAR and DAR subject is quite a big one!

As the bulk of my encodes are generated at 1:1 and contain either 720x480 or 720x576 pixels (ie: they are not cropped or re-sized) I personally prefer to use DAR. I do this for a couple of reasons: -

First: because Mpeg2 uses DAR.
Second: because, after generating extensive tests, I've found Mpeg4 encodes with DAR, position the pixels in the exactly the same place as the Mpeg2 source.

The sad fact is though, it's taken many years for PAR/DAR signalling to be included within the Mpeg4 stream. And it's taking even longer for codec manufacturers to re-write their video DSdec filters to recognise the signalling. So... until everybody supports the function, users are getting confused :(


Cheers

[yaz]

Originally posted by DARcode
... how should PAR and DAR interact? ... actually, DAR = PAR x SAR (SAR=storage AR) but ...
- before u go for xARing consider what seemoredigital wrote
- check your (calculated) AR w/ffdshow before you set it in the stream
the bests
y

[unskinnyboy]

If you just want to resize it to 16:9 while playback, in addition to all these methods you can also use ffdshow to resize on-the-fly.

Go to ffdshow --> Configuration --> ffdshow Properties --> Check 'Resize & aspect settings'.

Inside that tab,

Check 'Process whole image'
Check 'Resize'
Under 'Resize', select 'Specify Aspect Ratio' to be 16:9.

Click 'Apply', 'OK'. Now play in any DirectShow player.:)

[sagar.n]

Thank You All for your kind suggestion. I got it done.

[DARcode]

Wow! That was fast and very helpful!
A big thank you, this forum, teh vid forum ;) , rawkz :) !