Re: gray point correction
Posted by Martin du Saire on Jan 12, 2006; 4:13pm
URL: http://imagej.273.s1.nabble.com/Serial-communication-tp3704088p3704093.html
Yeah. Now that makes absolute sense. Thanks.
Question: Do you normalize to the highest mean if the patch is dark
gray, and the lowest mean if it is light gray?
Do you think this kind of color correction can compensate for
variability in natural lighting imaging?
Thanks again.
M
At 08:38 PM 1/11/2006, you wrote:
>I've done this kind of white balancing manually in ImageJ before.
>The technique is relatively straightforward and could be turned into
>a macro if you need to do it often. Here's how I did it.
>
>A patch is gray or white when the values of the 3 color channels
>(red, green & blue) are equal. So 1st you need to figure out the
>factors you need to multiply the lower channels by to make them
>equal to the brighter channel. Here's what I did.