Quicktime changes the aspect ratio on it’s own

[Dennis Leppell]

[Christy Pessagno] “I understand that it is probably compromising for the square vs rectangular pixels, but how does this automatic change affect other things, like when we bring the file into dvd studio pro, or want to stream it out to a tv?”

This automatic change is because QT Export wants to make it a video to be viewed on your computer. That’s why you need to manually change the settings of the dimensions.

If you send your 640×480 picture to DVD SP you’re going to need to again customize the picture size, adding another level of rendering to the piece, and resulting the final piece not being as good as it could be.

To correct the problem, you should export only as a self-contained reference file
Export >> Quicktime Movie >> Current Settings.
Be sure that self-contained is checked. This will give you your 720×480, the resultant file will be as good as you can get possibly get out of FCP, and the export itself is very quick.

[Christy Pessagno]

Thanks Dennis.
So my original solution of doing a custom size export if you are exporting out of Quicktime rather than FCP will also work for that. I just wanted to make sure there wasn’t an unnecessary step i was taking in trying to keep the aspect ratio at rectangular 4:3.

[Dennis Leppell]

Just to verify, you were originally exporting from FCP using export ====>Quicktime Conversion? If so, that’s why the frame size is being changed. You want to export=====>quicktime movie, and use current settings. This will keep your aspect ratio at 4:3 with rectangular pixels. From there you can use Compressor or Quicktime to change to 640×480 with square pixels

[Alan Okey]

Just to add confusion to the mix, Quicktime Player is savvy about certain SD video formats – DV and MPEG-2, for example. Quicktime Player will display a 720×480 DV or MPEG-2 movie as 640×480 on screen when played back. This is merely an aspect ratio correction for playback (i.e. 720×480 nonsquare pixels displayed as 640×480 square pixels), and does not change the actual file. This can be confusing for people who expect to see nonsquare pixel output.

[John Woods]

I have a similar problem when exporting 720×480 interlaced using Compressor. What Compressor 2 generates, with setting standard NTSC 4:3, is an MPEG2 movie that QuickTime describes as 640×480.

From some of this thread, I get the idea that this MPEG2 movie is really 720×480, and it is just that QuickTime seems to say otherwise, referring to its own display on the computer screen rather than to the movie file itself. But other parts of the thread lead me to believe that the created movie file really is 640×480, and that I need to use a special setting in Compressor to generate a real 720×480 movie. Can someone clarify this?

Thanks,
John

John Woods
WOODS Productions
Clifton Park, NY, USA

[Asimo Honda]

Interesting stuff. However, I feel like my situation is opposite. In FCP I’m looking at NTSC format which should be rectangular pixels. When I open my captured footage in Quicktime, it’s not squished width wise. It’s stretch width wise. Does this make sense? What’s the deal?

[Dave Walker]

My experience is that it is a new movie that is 640×480. It goes in 720x480DV and comes out 640x480MPEG-2. When you import it into DV Studio Pro, it’s a square pixel movie. In one scenario, I went into QT and manually changed the frame size back to 720×480. Then, I re-saved the movie. DSP didn’t like this file and wouldn’t import it. This is a real fine mess!