algorithms for automatically cropping?

[Michael Howard]

IM wizards,

My question is not directly an IM question, but relates to algorithms
/ techniques for automatically cropping images ...

I need to crop a bunch of photos to square while creating thumbnails.
I am currently using ImageMagick to crop the largest square from the
center of the photo ... works fine.

I am wondering if there are algorithms that could do a better job of
identifying the more interesting parts of a photo (like simple face
detection) or eliminating relatively uninteresting parts of a photo
(like blue sky or white walls).

Doesn't have to be perfect. I am just looking for a simple improvement
over grabbing the square from the center of the photo.

Any feedback / advice / experiences would be appreciated.


Michael

[Anthony Thyssen]

On Wed, 20 Jul 2011 16:12:25 -0400
magick-users-***@imagemagick.org wrote:
| IM wizards,
|
| My question is not directly an IM question, but relates to algorithms
| / techniques for automatically cropping images ...
|
| I need to crop a bunch of photos to square while creating thumbnails.
| I am currently using ImageMagick to crop the largest square from the
| center of the photo ... works fine.
|
| I am wondering if there are algorithms that could do a better job of
| identifying the more interesting parts of a photo (like simple face
| detection) or eliminating relatively uninteresting parts of a photo
| (like blue sky or white walls).
|
| Doesn't have to be perfect. I am just looking for a simple improvement
| over grabbing the square from the center of the photo.
|
| Any feedback / advice / experiences would be appreciated.
|

There are methods: edge detect, blur, threshold trim, and then locate
result, to find a 'center' or interest. But they are never perfect.

Post your question on the IM Discussion forum, in Digital Image Processing
as it is something more people (not on email list) may like to
contribute to.



Anthony Thyssen ( System Programmer ) <***@griffith.edu.au>
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