Changing the aspect ratio of an AVI

Clement Saggers · 04-15-2009, 01:34 PM

I make a lot of YouTube videos, and my camera can shoot in widescreen hi-def. I like to use 1280x720 as it matches the new YouTube High Definition video resolution. I edit in Adobe Premiere 6.5 (I know it's old but it works), and export the video as an XviD move with AC3 audio, if I upload that to YouTube, even though it's been exported at 1280x720, on Youtube it appears as 4:3, even tho I have all the video settings on Premiere set to 16:9! However, if I re-encode the video in e-rightsoft Super and upload that video, it appears on YouTube the way it should. The only thing I can think of is that there must be some data somewhere in the avi files that tells whether it's 16:9 or 4:3, and Premiere does not write that data into the file. Is there a program anywhere that can change that little bit of data, because I don't want to have to re-encode a video, just so the thing can tell that's it's 16:9.

**zuluclayman** · 04-15-2009, 06:48 PM

I'm not sure about Premiere Pro 6 (I use Premiere Elements 7) but if I go to File > Export > Movie a dialogue box pops up asking where to save to and also has a Settings button where I choose Microsoft AVI then under the Video tab I can choose the pixel aspect ratio from a list of 8 or so choices.
You should be able to choose the aspect ratio that suits your output from there. Try the one you think will suit and if that fails try the square pixels option first then others until you arrive at the one that will give you the aspect ratio you want.

**blah789** · 04-16-2009, 11:32 AM

There's a caveat though. Some players (I think WMP is one of them) ignore that info (the metadata about pixel aspect ratio). I think VLC will read it though. (I once had an Xvid video that had that problem - and it had weird aspect ratio in WMP, but played fine in VLC, hence my inferences).
If you want to play it safe (who knows whether the youtube converting scripts read the metadata?), just letterbox it. Letterbox = add black spaces on top and on bottom until the ratio is 4:3. The maths says your video should come out 1280x960, with two black strips 96 pixels high, one on top and one on the bottom.

If you still want to write the metadata, and you're encoding in xvid, go to advanced properties, and where it says profile@level, click on more. The aspect ratio can be set under the aspect ratio tab. Not sure where the setting is in other codecs.

04-15-2009, 01:34 PM	#1 (permalink)
Clement Saggers Registered User Join Date: Apr 2008 Location: Newmarket, England Posts: 63 OS: Windows XP SP2, Windows XP64 & Windows 2000	Changing the aspect ratio of an AVI I make a lot of YouTube videos, and my camera can shoot in widescreen hi-def. I like to use 1280x720 as it matches the new YouTube High Definition video resolution. I edit in Adobe Premiere 6.5 (I know it's old but it works), and export the video as an XviD move with AC3 audio, if I upload that to YouTube, even though it's been exported at 1280x720, on Youtube it appears as 4:3, even tho I have all the video settings on Premiere set to 16:9! However, if I re-encode the video in e-rightsoft Super and upload that video, it appears on YouTube the way it should. The only thing I can think of is that there must be some data somewhere in the avi files that tells whether it's 16:9 or 4:3, and Premiere does not write that data into the file. Is there a program anywhere that can change that little bit of data, because I don't want to have to re-encode a video, just so the thing can tell that's it's 16:9.

04-15-2009, 06:48 PM	#2 (permalink)
zuluclayman Design Team Member Join Date: Dec 2005 Location: Newcastle, Australia Posts: 3,049 OS: Windows Vista Home Premium My System	Re: Changing the aspect ratio of an AVI I'm not sure about Premiere Pro 6 (I use Premiere Elements 7) but if I go to File > Export > Movie a dialogue box pops up asking where to save to and also has a Settings button where I choose Microsoft AVI then under the Video tab I can choose the pixel aspect ratio from a list of 8 or so choices. You should be able to choose the aspect ratio that suits your output from there. Try the one you think will suit and if that fails try the square pixels option first then others until you arrive at the one that will give you the aspect ratio you want. __________________ AutoGordianKnot Audacity K-Lite codec pack Irfan View GSpot TSF Photographer's Corner

04-16-2009, 11:32 AM	#3 (permalink)
blah789 TSF Enthusiast Join Date: Aug 2008 Posts: 2,294 OS: Windows 2000 SP4 and Windows XP SP3	Re: Changing the aspect ratio of an AVI There's a caveat though. Some players (I think WMP is one of them) ignore that info (the metadata about pixel aspect ratio). I think VLC will read it though. (I once had an Xvid video that had that problem - and it had weird aspect ratio in WMP, but played fine in VLC, hence my inferences). If you want to play it safe (who knows whether the youtube converting scripts read the metadata?), just letterbox it. Letterbox = add black spaces on top and on bottom until the ratio is 4:3. The maths says your video should come out 1280x960, with two black strips 96 pixels high, one on top and one on the bottom. If you still want to write the metadata, and you're encoding in xvid, go to advanced properties, and where it says profile@level, click on more. The aspect ratio can be set under the aspect ratio tab. Not sure where the setting is in other codecs.