Help me fix the aspect ratio on this .MOV!

April 30, 2008 7:21 PM

Help me fix the aspect ratio of this .MOV video, please! It's an emergency!

Okay, I've got a .MOV here, right? It's supposed to be in 4:3 aspect ratio. The problem is that the file is in 4:3, but the video is in widescreen, and it's all squashed short and fat, with black letterbox bars on the top and bottom! I need to fix this and get it up on YouTube right now, but I know next to nothing about video editing. What free software can I use to fix this quickly? If there are any volunteers, I can also e-mail it someone who can fix it and e-mail it back. Thank you, AskMe!

posted by Faint of Butt to computers & internet (15 comments total)

Sounds like something ffmpeg (free) should be able to handle, though I don't know the commands you'd use.
posted by sanko at 7:36 PM on April 30

I'm virtually positive I can fix it, but you will lose quality, despite my best efforts. E-mail me.
posted by chudmonkey at 7:45 PM on April 30

If you choose to e-mail me, don't attach the file immediately - depending on it's size, I may not be able to receive it.
posted by chudmonkey at 7:55 PM on April 30

If you're on Windows, and the .MOV uses H.264 video, you can do it losslessly:
1) Get YAMB (Yet Another MP4Box UI).
2)Open Yamb, select "Creation", and within that menu select "Click to create an MP4 filer with blah blah" and select your MOV file. Wait up to maybe 20 seconds as it reads the streams.
3) Highlight the H.264 stream and click the "Properties" button on the right side of the YAMB window.
4) From the drop-down "Pixels Aspect Ratio" menu, select a value that will give you the dimensions you desire. Presumably you want to go from 16:9 to 4:3, so you can select "4:3 NTSC" (or "4:3 PAL" if you're European) from the dropdown menu. If the video PAR is 4:3 and it still looks like that, someone probably goofed and made the PAR AND the SAR 4:3, so a "1:1" pixel aspect ratio should set you straight.
5) Select the output file (DO NOT OVERWRITE THE ORIGINAL), and click "next". Wait as the streams are demuxed and remuxed...this will take a few minutes depending on the length of the movie.
6) You can safely re-name the output Movie.MP4 file to Movie.MOV, as the streams within will still be Quicktime compliant. If Youtube accepts MP4 input, skip this step.
7) Profit!
posted by Inspector.Gadget at 8:01 PM on April 30

Inspector.Gadget, thanks for the attempt, but that didn't work, either with the 4:3 or 1:1 setting.
posted by Faint of Butt at 8:10 PM on April 30

Where did it break? Can you try doing it from the command line? (YAMB is kind of buggy).
posted by Inspector.Gadget at 8:15 PM on April 30

It processed everything just fine, or seemed to, but the resulting MP4 looked exactly the same as the MOV.
posted by Faint of Butt at 8:17 PM on April 30

Oh. Hmm...well, maybe try the command line. I know the tagger function in YAMB can be sort of screwy, but I always assumed that only extended to user-defined art metadata of the sort that the Atomic Parsley library handled.
posted by Inspector.Gadget at 8:19 PM on April 30

Maybe try demuxing with YAMB, editing the H.264 stream aspect ratio directly with H264info, then remuxing.
posted by Inspector.Gadget at 8:26 PM on April 30

YAMB worked for me on Windows Vista to edit an H.264 stream's aspect ratio in an MP4 container - I just made Alien vs. Predator totally warped looking. What OS are you running? And what are the properties of the stream itself?
posted by Inspector.Gadget at 8:28 PM on April 30

If chudmonkey cannot do it, I expect I could -- not instantly, but tonight. My email's in my profile. I'm no master video editor but I've done virtually this exact procedure in quicktime pro.
posted by churl at 8:54 PM on April 30

Thanks to everyone willing to help out. Forgive me, but I'm going to bed. If anyone has any more ideas, though, I'd love to hear them!
posted by Faint of Butt at 9:59 PM on April 30

If the black letterbox bars have actually been encoded into the video itself, and are not simply an artefact of the aspect ratio having been set wrong, you will need to crop them off and recode. Try fooling about with

mplayer -vf cropdetect

followed by

mencoder -vf crop=width:height:left:top,dsize=4/3 -oac copy -ovc x264 -o /path/to/output/file.mov /path/to/input/file.mov
posted by flabdablet at 12:06 AM on May 1

chudmonkey fixed it all! Huzzah!
posted by Faint of Butt at 3:15 AM on May 1

Well, rather than converting it, if you send it to me, I'll use quicktime pro to fix the proportions. It's nondestructive to the pixels.
posted by filmgeek at 6:19 PM on May 1