Color-coding done, but brightness coding?

Share icon

Hello!
I'm building a Direction Selectivity Map in which I try to represent for the 24 ROI their preferred direction. To do this I color coded the preferred angle of each ROI, but I would also like to show in the same image the significance of the direction by changing the brightness of the colors.
Is that possible with Igor?

Until now I manage only to do 2 separate maps (attached), but I would like to represent all in the same one.

Thanks ;)
If you want to use intensity or brightness you can find various color-space translations in the ImageTransform operation. Specifically, you can choose the hue value (in HSL space) and vary the lightness scale on a fixed saturation, then translate the color to RGB and use it to paint your rectangles.

I am not sure how effective this method may be. After all, intensities may not be so easy to differentiate and they are certainly not linear so they are not an ideal display parameter. You may want to consider a different approach. For example, you could draw a different size arrow so that it provides both the direction and the relative significance is coded in the length of the arrow. Otherwise you might want to consider moving your display to 3D where you may have more options.

A.G.
WaveMetrics, Inc.

March 5, 2015 at 08:33 am - Permalink