[racket] how can I change image's tint?

-----BEGIN PGP SIGNED MESSAGE-----
Hash: SHA1

On 10/23/2010 08:38 PM, 김태윤 wrote:
> there must be easy way to change tint(hue, shade) of image
> but how to?
> thanks in advanced

A way, sure, but not an easy way. Racket doesn't have a full featured
image processor and photo filter chain ala GIMP/Photoshop, mostly
because that would be just too much damn work. Use the previous
suggestion, or just use two images, with two different tints, and
alternate between them. Or if you really want you could map each pixel
into the colorspace and rotate it through that space a certain amount to
alter the hue. I'd just use the GIMP honestly.

http://en.wikipedia.org/wiki/HSL_and_HSV

You might also be able to do something fancy with sgl OpenGL and lighting.
-----BEGIN PGP SIGNATURE-----
Version: GnuPG v2.0.14 (GNU/Linux)
Comment: Using GnuPG with Mozilla - http://enigmail.mozdev.org/

iQEcBAEBAgAGBQJMw7uHAAoJECC/cKf8E7UIUU4IAJd9vt6RzalbmVKZpEDeiX7O
w+8TK/cpDLFGdIs7Lm5A8BfFfgD35v9WIXca4aHn1uj7bvZ4TWFKCK9eboW6xlnX
ThmF1//q1VnTyEjQs84efZf1Fa2CurD1beavzBc2tmE+GIn0REcaoTzEmTjc+bAs
xJoyxt3GsajlmR7xhhA+bgBRDemf4Wgts10mvSye+q11QO6X9ZQJQxRiHk9ZASsK
FqFOyF3cQDhNTg05HxHaKjOEry4BEI96pstxYJuQwPI4YfR0e4q86YwwtLPOZZL7
SIyPMvk0avRbFIzgbUpnZFAjImfENchFE1Ck6QbANnKPhaTUaPB7jbZ2rOC4H/k=
=og1Q
-----END PGP SIGNATURE-----