Best resizer for 720x480 to 640x480?

[stevevid]

Is Spline36Resize, BilinearResize, or another tool best for converting 720x480 captures to 640x480?

Thanks,
Steve

[lordsmurf]

Crop 720>704, then resize, if this is a VHS tape source.

Resize method really depends on the content. There's no single best method. Sometimes simple bicubic or bilinear appears best, while other times a spline or lanzcos looks better. You need to find some test areas, apply the filter, preview the aliasing noise and blur.

[stevevid]

Thanks!

I was planning to have "Crop(4,0,-8,-8).AddBorders(6,4,6,4)" before the resize. My crop is a bit smaller that what I've seen you use because the left side doesn't have much trash.

I recall reading that the black areas on the side of a 720 wide capture don't count toward the 4:3 aspect ratio and should be cut off before resizing--true? Is the switching noise at the bottom also not part of the 4:3 ratio and should be cropped off? I don't recall reading anything that mentioned the bottom trash was outside the 4:3 ratio space.

Should I go with the crop and border approach I was planning on using or should I just do an even crop from both sides to get 704 across with no top & bottom crop, resize to 640x480, then mask the bottom trash after the resize?

Thanks,
Steve

BTW: I will be outputting a 640x480 progressive video

[latreche34]

Quote:

Originally Posted by stevevid

I recall reading that the black areas on the side of a 720 wide capture don't count toward the 4:3 aspect ratio and should be cut off before resizing--true?

Yes, that's the D1 standard, ITU-R 601 (orig. CCIR-601), a.k.a Rec. 601 by SMPTE engineering committees.

Quote:

Originally Posted by stevevid

Is the switching noise at the bottom also not part of the 4:3 ratio and should be cropped off? I don't recall reading anything that mentioned the bottom trash was outside the 4:3 ratio space.

No, Unless your capture device captures at 486 lines then you get the luxury of cropping off those 6 lines from anywhere you want, top, bottom or a combination of top and bottom.

[themaster1]

The rule of thumb : if you want to upscale you want sharp so you should use spline36 (or 64)
for a downscale you might want to smooth details thus: bilinear.