GDI+: Modifying an image's R/G/B-channels

[Olaf Rabbachin]

Hi folks,

I'd like to modify an image's RGB-channels (i.e. two buttons +/- for each
channel) using a ColorMatrix.
However, I just don't find the right value(s) (coordinates) to be changed.

Any suggestions?

Thanks,
Olaf

 

[Ken Tucker [MVP]]

Hi,

There is a vb.net and c# sample here.
http://www.bobpowell.net/image_contrast.htm

Ken
-----------------
Hi folks,

I'd like to modify an image's RGB-channels (i.e. two buttons +/- for each
channel) using a ColorMatrix.
However, I just don't find the right value(s) (coordinates) to be changed.

Any suggestions?

Thanks,
Olaf

 

[Olaf Rabbachin]

Hi,

I'd like to modify an image's RGB-channels (i.e. two buttons +/- for each
channel) using a ColorMatrix.
However, I just don't find the right value(s) (coordinates) to be changed.

Got it - it's the first three columns on the last row (Alpha on the fourth
column):

1 0 0 0 0
0 1 0 0 0
0 0 1 0 0
0 0 0 1 0
R G B A 1

Cheers,
Olaf