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Topic: Bicubic spline bug/NEDI

Hello Michael,

first thank you for developing this great image processing software for years.

I've found a bug which might be there since version 1.31(?). At least on 64bit systems (Win7, Debian) bicubic spline resize is damaging images. It introduces some weird lines to them. It should be fixed sometime.

Btw. haven't you been thinking about implementing NEDI? (google: new edge directed interpolation - alexey lukin). His demo scales up in quality comparable with the most expensive resizing software.
I know about Fractal Interpolation/Xin Li but I'm not sure if it is the same.

Enjoy the rest of your holiday!

Adam

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Re: Bicubic spline bug/NEDI

Thanks.
I will take a look at this bug when I get back.

NEDI is actually in IA - it is just called Wiener in the normal resize dialog because it is basically a kind of Wiener filter.

Michael Vinther

> software developer <

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Re: Bicubic spline bug/NEDI

Thanks for the explanation. I didn't know it. It seems that Lukin's SmartEdge2 NEDI implementation works in a somehow different way. Just for information - I put a small example comparison here:

https://skydrive.live.com/redir.aspx?ci … parid=root

(Original was downsized by Lanczos, a=3 to 25%, then upsized to its original size.)

Note: I've uploaded bicubic spline damaged sample image at the same place.

Best regards
Adam

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Re: Bicubic spline bug/NEDI

I don't know why there is such a big difference - as far as I remember my implementation is fairly close to the algorithm described in the original paper.

Michael Vinther

> software developer <

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Re: Bicubic spline bug/NEDI

The bicubic spline interpolation bug should be fixed in the latest beta.

Michael Vinther

> software developer <