Re: RGB weights and fluorescence intensity

Posted by Sami Badawi-2 on Jul 23, 2009; 3:50am
URL: http://imagej.273.s1.nabble.com/RGB-weights-and-fluorescence-intensity-tp3691651p3691654.html

Hi Sinead,

You should integrate / add the color or intensity in the thresholded
area and divide it by the area.

It is normal to weight the RGB colors differently:
Intensity = 0.3*R + 0.59*G + 0.11*B
The reason for this is that we have less blue cones receptors in our
eyes than red and green cones.

The ShapeLogic plugin has a color particle analyzer that calculates
both average intensity and average color or colored spots.

-Sami Badawi
http://www.shapelogic.org

On Wed, Jul 22, 2009 at 10:56 AM, Sinead Roberts<[hidden email]> wrote:

> Dear all,
>
> I want to calculate the fluorescence intensity from an RGB image that I have thresholded. So to know
> the total fluorescence intensity in a ROI am I right in thinking I can take the 'integrated density' value
> in the measurements section? Also, should I calculate the brightness value with or without weighted
> RGBs? What is the weighting for?
>
> Thank you very much for your help, I am afraid I know very little about the principles of image
> analysis and processing,
>
> Sinead
>