Image J Q: Colour percentages

[Brian Ross-3]

Gday all,
I was hoping someone could tell me how I can find out the percentage of green that is in a photo.  Either in pixels, hues or area.  Any way is fine.  I am doing a study which requires me to find out how the colour of a site changes with time.  Would be very appreciative if anyone can help.  Cheers,
Rossy.

[Harry Parker]

Hi Rossy,

Check out the ImageJ Plugins web page for many options. For example, "RGB Measure" writes the average red, green and blue values of an image into a table that can be copied or saved to a file. Other plugins in the Color category give more information.

To automate this, check out the Developer Resources pages, particularly the pages on the Macro language and the macro functions. You can call ImageJ macros from an external script that grabs images of web pages. Many examples are linked from the page on macro functions. Over a thousand example macros are available to help you get started.

 
--
Harry Parker
Senior Imaging Systems Engineer
Digital Imaging Systems, Inc.



----- Original Message ----
From: Brian Ross <[hidden email]>
To: [hidden email]
Sent: Saturday, October 4, 2008 7:05:15 PM
Subject: Image J Q: Colour percentages

Gday all,
I was hoping someone could tell me how I can find out the percentage of green that is in a photo.  Either in pixels, hues or area.  Any way is fine.  I am doing a study which requires me to find out how the colour of a site changes with time.  Would be very appreciative if anyone can help.  Cheers,
Rossy.