How to measure the hue using ImageJ?

Hi there, I’m new to image analysis and 've been playing with ImageJ for the last two days. I hope I;m not asking a stupid question, but I’m confused as to how to get the Hue value for an image.
I have RGB images. What I have done is adjusting colour threshold–selecting HSB for color space–adjusting ‘Hue, Saturation, Brightness’ separately until the area I want to analyse is covered in red–then clicking ‘select’–going to ‘Histogram’ in ‘analyse’. And then I got the result with min, max, mean, etc. But I am not sure if the values are for Hue or Brightness or something else?
Anyone could help?

Thanks, Summer

Hello Summer -

If you run Image > Type > HSB Stack from the Fiji / ImageJ
menu bar (with your RGB image of interest selected), you will
get a three-channel stack. You can now do your measurements
on the “Hue” channel.

(If for some reason you wish to work with a single non-stack image,
you can run Image > Stacks > Stack to Images to get your
“Hue” channel into a single image.)

Does this work for what you need to do?

Thanks, mm

2 Likes

Hi mm,
Thank you for your answer. I got the single Hue image, which is great.
Though I have another question that. after getting the image, would you know that how I can use some sort of auto-selection to outline the area where I want to measure the Hue? Or is it possible to select the area first and then get the Hue channel?
The shape is irregular, but it is distinct from the background colour. So I am thinking to remove the background first but I haven’t found how to do that.
Thanks, Summer