l i n u x - u s e r s - g r o u p - o f - d a v i s
Next Meeting:
July 7: Social gathering
Next Installfest:
Latest News:
Jun. 14: June LUGOD meeting cancelled
Page last updated:
2007 Feb 22 07:29

The following is an archive of a post made to our 'vox-tech mailing list' by one of its subscribers.

Report this post as spam:

(Enter your email address)
Re: [vox-tech] count pixels
[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

Re: [vox-tech] count pixels

On Wed, Feb 21, 2007 at 07:27:20PM -0800, Wade Pinkston wrote:
> Hash: SHA1
> Hello,  I need to process some images and count the number of pixes of a
> given color.
> A little background.  I want to take pix of leaves against a mat
> background.  The leaves are then subjected to damage.  I'll then take a
> duplicate photo.  Now what I want to do is subtract out the colors of the
> leaf leaving only a two tone image.
> I was hoping to find a way to then use ImageMagick or Gimp to count the
> pixels of color so I can then get a percent change between the two images.
> Does anybody know how to get ether of these two programs to give this type
> of information.  Actually any software would be help full.

If the image is in an indexed format, you can use identify from the
imagemagick suite:

$ identify -verbose some.gif
       155: (238,238,238,  0)   #EEEEEE00
       244: (245,245,242,  0)   #F5F5F200
       264: (249,249,249,  0)   #F9F9F900
       139: (252,252,252,  0)   grey99
      3885: (255,255,255,  0)   white
      3197: (235,235,217,255)   #EBEBD9FF

This shows that this image has 3,885 white pixels.


vox-tech mailing list

LUGOD Group on LinkedIn
Sign up for LUGOD event announcements
Your email address:
LUGOD Group on Facebook
'Like' LUGOD on Facebook:

Hosting provided by:
Sunset Systems
Sunset Systems offers preconfigured Linux systems, remote system administration and custom software development.

LUGOD: Linux Users' Group of Davis
PO Box 2082, Davis, CA 95617
Contact Us

LUGOD is a 501(c)7 non-profit organization
based in Davis, California
and serving the Sacramento area.
"Linux" is a trademark of Linus Torvalds.

Sponsored in part by:
Sunset Systems
Who graciously hosts our website & mailing lists!