Determining Aspect Ratios for Future Projects...

[Ryujisama]

Hello AMV creators, one and all. I have a bit of a dillema. I have an idea for an AMV, but I'm a little skeptical on how to go about on ripping the videos from DVDs. I use the program apptly called AOA DVD Ripper. Now, I pretty much know how to work the software, but my main problem is thus: When ripping the clips I want off of a DVD how do I go about ripping the clips in the right aspect ratio? What can I do to determine the aspect ratio of future DVDs that I choose to rip clips from? Please help me out on this.

[Kariudo]

you can't do too much about the aspect ratio when you rip (you may be able to do it...I use dvdDecrypter...but you can't do anything about the AR in that)

dvds have a certain AR (usually 4:3 (fullscreen), 16:9 (widescreen) or 1.85:1 (anamorphic widescreen))
You can resize and/or add borders to footage to make the footage have the right resolution (usually you make widescreen footage into fullscreen resolution...at least that's what I've seen the most).

If you just resize, the footage won't look right (it'l either look stretched horizontally or vertically)

this is only really a problem when you want to use footage with 2 or more different ARs (otherwise you can pretty much ignore the AR)

http://www.animemusicvideos.org/guides/ ... deo1.htm#4
and
http://www.animemusicvideos.org/guides/ ... ocId742447
and
http://www.animemusicvideos.org/guides/ ... atios.html
should go over everything you want to know

[trythil]

you can't do too much about the aspect ratio when you rip (you may be able to do it...I use dvdDecrypter...but you can't do anything about the AR in that)

dvds have a certain AR (usually 4:3 (fullscreen), 16:9 (widescreen) or 1.85:1 (anamorphic widescreen))

MPEG-2 defines display aspect ratios of 1:1, 4:3, 16:9, and 2.11:1. The most commonly used display aspect ratios for DVDs are 4:3 and 16:9. For display aspect ratios such as 1.85:1 and 2.35:1, encoding at 16:9 with appropriate letterboxing is common.

On the subject of how to tell: the DVD jacket is usually the best first place to look. AnimeOnDVD is one site that has aspect ratio information along with all its DVD reviews; there's more out there.

You can resize and/or add borders to footage to make the footage have the right resolution (usually you make widescreen footage into fullscreen resolution...at least that's what I've seen the most).

A far better solution is to crop and resize the material so that it will look correct on your target device. In the case of computer monitors, you can obtain a good approximation by assuming a pixel is square, and performing the appropriate transformations. The A/V tech guides contain quick procedures for doing this, as well as a calculator should you want to obtain more accurate results.

An even better solution is to do all your video work at the display aspect ratio of your source footage and then encode that as-is with the proper display/pixel aspect ratio flags set. Modern video containers such as Quicktime, Matroska, and the MPEG-4 container support such flags. Unfortunately, a lot of people are still using players which cannot properly interpret such information, but the method I described above is definitely the way to go in future.

this is only really a problem when you want to use footage with 2 or more different ARs (otherwise you can pretty much ignore the AR)

You can't ever ignore the aspect ratios you're working at. If you do, your circles will end up as ellipses, characters will either lose or gain 25 pounds, and things will in general just look bad.