Scrambed LUT

[Aaron Bell]

Hello--
 
I have an RGB image that I'd like to convert to an 8-bit color image but
with an unscrambled LUT. By unscrambled, the colors are organized based on a
spectrum or colors sorted using an equation like the histogram's gray
formula (gray=0.299red+0.587green+0.114blue) or similar. I can't seem to do
this with ImageJ's built-in converter; the resulting LUT is scrambled. I
know converting to 8-bit grayscale unscrambles the LUT, but then I lose the
color information.
 
I want to do this so I can apply a threshold to darker areas of the image
for later measuring.
 
Any ideas?
 
Thanks,
Aaron
 
________________________
Aaron Bell :: AI Project Manager
Stottler Henke Associates, Inc.
ph: 650-931-2700  |  fx: 650-931-2701
951 mariner's island blvd  |  suite 360  |  san mateo, ca 94404
www.stottlerhenke.com <http://www.stottlerhenke.com/>
 
 

[Joel Sheffield]

This is an interesting problem.  The conventional 8bit indexed color
lut is indeed a complex structure.  Would it be simpler to separate
the channels (i.e. use the Image>Color>RGB Split) and see about
isolating the features you want using the separate colors?  You could
then recombine them to result in a modified RGB image.

> Hello--
>
> I have an RGB image that I'd like to convert to an 8-bit color image
> but with an unscrambled LUT. By unscrambled, the colors are organized
> based on a spectrum or colors sorted using an equation like the
> histogram's gray formula (gray=0.299red+0.587green+0.114blue) or
> similar. I can't seem to do this with ImageJ's built-in converter; the
> resulting LUT is scrambled. I know converting to 8-bit grayscale
> unscrambles the LUT, but then I lose the color information.
>
> I want to do this so I can apply a threshold to darker areas of the
> image for later measuring.
>
> Any ideas?
>
> Thanks,
> Aaron
>
> ________________________
> Aaron Bell :: AI Project Manager
> Stottler Henke Associates, Inc.
> ph: 650-931-2700  |  fx: 650-931-2701
> 951 mariner's island blvd  |  suite 360  |  san mateo, ca 94404
> www.stottlerhenke.com <http://www.stottlerhenke.com/>
>
>

Joel B. Sheffield, Ph.D.
Biology Department, Temple University
1900 North 12th Street
Philadelphia, PA 19122
[hidden email]  
[phone], fax [phone]
http://astro.temple.edu/~jbs