High Action...De-Interlace Before or After Resize?

[angelleye]

I've got lots of high action sports captures that I'm encoding to Divx. I've been adding the Resize filter first and then De-Interlacing afterwards and I'm happy with my results...but I'm curious if I'd get better results doing it the other way around.

Any info would be great.

Thanks!

[DigitAl56K]

You must de-interlace before resizing! If you don't the two fields will be blended together during the resize operation, and weird things will happen depending on the resize filter. The de-interlace won't work properly after the resize because the fields will not occupy discrete alternating lines and the field order will be lost.

[angelleye]

wow, i've been doing it wrong all this time. From what guides I had read I miscalculated apparently. I was thinking that by resizing first the encodes would be quicker because it wouldn't have to de-interlace such a large shot. My clips usually look pretty good...I capture off high def (not a high def card though) and I resize to 640x352. I do see weird wavy parts at times that kind of look like interlacing...but not. I guess those are what you're talking about.

I appreciate your information and I look forward to better looking video. :)

Thanks!

[jggimi]

If you are resizing to 1/2 height (or smaller) than you won't need to deinterlace at all, since interlace artifacts will not be present in the frames. -- e.g.: 480 to 240, or 576 to 288.