DVD aspect ratio wierdness

Chris F · Post by **Chris F** » Sun Sep 04, 2005 9:22 am

I've just started working on my first video editing project, and have a number of questions.

The video I'm using is full-frame on my TV, so the aspect ratio ought to be 4:3, right? However, my computer indicates the resolution is 720x480, not 640x480. What's going on here?

Al'x · Post by **Al'x** » Sun Sep 04, 2005 9:57 am

the trick is that the pixels are not squares

http://www.animemusicvideos.org/guides/ ... ocId742447 (look at PAR vs. DAR)

Chris F · Post by **Chris F** » Sun Sep 04, 2005 10:32 am

Let me see if I understand this. Basically, the disc's DAR vertically stretches the image a little bit but this effect is cancelled out by the TV's PAR?

Scintilla · Post by **Scintilla** » Sun Sep 04, 2005 10:36 am

Chris F wrote:Basically, the disc's DAR vertically stretches the image a little bit but this effect is cancelled out by the TV's PAR?

If by "vertically" you mean "horizontally" (in NTSC Land, which I assume you're in because you said 720x480), then yes.

When you're done editing a video and are compressing it for internet distribution, you want something that will look right when played back on a computer monitor (which DOES have square pixels), so you'd change the resolution to something that's mathematically 4:3, like 640x480 or 512x384.

Unless you are encoding an MPEG-1 and want to use the 4:3 aspect ratio flag so you don't have to resize at all.