# aspect ratio conversion for mpeg2 video



## Fingerprints (Jun 23, 2006)

I need a little bit of help here.  i know one solution to my problem, but it is very time consuming and i want a quicker fix.  i've got an mpeg2 video file that has dimensions of 720x404 (1.73) and i need it to be 4:3 (720x540).  what i'm saying in plain english is I need to maintain the aspect ratio of the video but add height to the frame so that it will play the proper/original aspect ratio on tv (having lots of black on top/bottom of frame of course).  It gets confusing when talking about the aspect ratio of the video file versus the video if that makes any sense.

can i do this with mpeg streamclip or compressor?  i have both.


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## magilum (Jul 1, 2006)

Here's an informative thread from DVD HQ. According to that, and this thread from Apple's list, the aspect ratio for an MPEG2 file is set by flag and can theoretically be changed without recompression.

As for a practical solution, I've never dealt with this myself (so I don't know whether the programs mentioned can do this). DVD HQ recommends an app called Pulldown. A quick search of VersionTracker turns up this MPEG Append Suite which seems to offer something similar to what you're looking for, though I'm unsure whether it offers a mechanism to letterbox the video, or just fudges the proportions to fit the screen.

I wish I had a conclusive answer for you.


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## adambyte (Jul 1, 2006)

You could.... throw it into a Final Cut sequence where the aspect ratio is 4:3, then export. That would give you black bars.


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## magilum (Jul 1, 2006)

adambyte said:
			
		

> You could.... throw it into a Final Cut sequence where the aspect ratio is 4:3, then export. That would give you black bars.



Ah, but would it keep the sound? It might have to be de-muxed somehow first.

I'm guessing this is a big file that's going right onto DVD as soon as the aspect ratio is sorted, which is why the poster doesn't want to have to process the file more than necessary.


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## adambyte (Jul 2, 2006)

I'm pretty sure the sound would be just fine... The sequence presets include all sorts of things, including MPEG-2. Sound may have to be "rendered," in order to hear it within Final Cut, but if that works, everything should be fine upon export...


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## Fingerprints (Jul 5, 2006)

thanks folks, i'll try the suggestions so far.  going into FCP is the solution i knew of but don't like.  it takes way more time than my ideal solution.  sound has to be rendered, and for my purposes i'd need to export using compressor with certain settings, so it adds too many extra steps.  i'll post what i find with the other suggestions.

thanks,
joel


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