Does anyone know a freeware image analysis programme where I can ask it to filter by number of cycles per imag

Question

I've looked in photoshop, but I don't know how 'radius' relates to cycles per image or cycles per number of pixels. I need two different spatial frequency bands, one band <6 cycles per image, and one band > 24 cycles per image. Cheers!

Answer 1

What kind of images are you trying to analyse? I am not familiar with a 'cycles per image' terminology. Cycles/frequency of what?

Radius, in Photoshop, probably refers to one of the blur/sharpness filters or similar and will refer to the number of pixels around a central point which are taken into account in the filter.

Since you have placed this in a science category, I am assuming you are analysing some specialist images concerning frequency data.