2.35:1 Resolutions

blaku92 · Post by **blaku92** » Tue Oct 21, 2008 9:29 pm

Ok, so I was wondering... I know that 848x480 and 640x480 are pretty much standard square pixel resolutions for 4:3 and 16:9 aspect ratios, but does anyone know what the standard is for 2.35:1 or 1.85:1 film ratios? I'm not talking HD, and of course, my stuff is in YV12, so lemme know what you guys crop/resize. Thanks!

Qyot27 · Post by **Qyot27** » Wed Oct 22, 2008 2:06 am

Adjusted to mod16,
1.85:1 (1/1.85=~37/20) would be either 880x480 or 896x480*
2.35:1 (1.2.35=~47/20) would be either 1120x480 or 1136x480**

*Actual is 888x480
**Actual is 1128x480

Usually though, 1.85:1 on DVD tends to be interchangeable with 16:9, as there tend not to be extravagant borders and the 16:9 anamorphic flag is still set.

What I would suggest concerning this would be this workflow:
A) Rip 2.35:1 movie.

B) Resize to 848x480 (since DVD only allows a 16:9 aspect flag even though MPEG-2 has one for 2.35:1 - which is why such movies are still letterboxed)

C) Crop the borders off using VDub's Null Transform filter.

D) Use the VDubMod Resize filter to scale the height up to 480, which also proportionally scales the width. You can optionally let it round to mod16 values as well. The value you want is the one furthest to the right in the filter's top bar.

Optional:
E) Use the Crop values and Resize values in a corresponding AviSynth script and bypass filtering in VDub.

The VDubMod Resize filter can be found here, and does not require being used in tandem with VDubMod (in other words, it works with vanilla VirtualDub too):
http://sourceforge.net/project/showfile ... _id=158229

Mosc · Post by **Mosc** » Wed Oct 22, 2008 6:13 am

My advice would be this, minimizing upscaling as much as possible while keeping most of the spatial information intact: 848x464 for 1.85, and 848x352 or 848x368 for 2.35. Still, upscaling is dumb and it's a whole lot easier to just use the same method for every aspect ratio you encounter:

1. Crop away black borders using AvsP, overcropping if necessary to ensure mod-16.
2. Set aspect ratio flag in mkvmerge GUI.

Less math, superior results.

blaku92 · Post by **blaku92** » Wed Oct 22, 2008 2:12 pm

Cool thanks, after doing some simple math I found some of these and other resolutions. I was just trying to see how most people would do this. I guess it's up to the individual then.