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futurex
14th May 2006, 13:45
Hello,

is there any advantage to doing anamorphic x264 encoding as opposed to just doing a regular crop and resize?

thanks!

bkman
14th May 2006, 13:51
Yes. You preserve more of the original resolution.

Oline 61
14th May 2006, 17:08
It's faster because there is no resize, x264 encodes fewer pixels, and you don't take up CPU cycles running a resizer.

And, as bkman said, it preserves more of the original resolution.

Caroliano
14th May 2006, 18:10
It's faster because there is no resize, x264 encodes fewer pixels, and you don't take up CPU cycles running a resizer.Fewer pixels? Fewer if you resize up (to 853x480 for example). But I think that the most common is to resize from 720x480 to 720x384. In that case it is slower to encode, and also slower to decode.

But it is true that you preserve more of the original resolution. You don't resize down a thing that you will resize up again in playback.

Oline 61
14th May 2006, 18:25
When I think of an anamorphic encode, I think of a widescreen DVD with an aspect ratio of about 2.35:1. I crop the black bars, so I have about 720x352 left (I usually just overcrop to achieve mod16). Then I encode with --sar 853:720.

This way I can use the more accurate, non-mod16 width (853) on playback, and encode fewer pixels than if I resize to 848x352.

I guess this is just one way to do anamorphic encoding.

futurex
15th May 2006, 01:07
thanks :)