Multiresolution Contrast Analysis Demo

This demo intends to present you a method we developped some time ago. Given an image, it creates an enhanced version of it which best keep all the contrasts (local and global). This program can also return a binary version of the input image.
Enter the URL of the image to proces. For security reasons, the URL must be fully specified, and thus local file accesses are not allowed. All images must be in pgm format and of size 2^n x 2^n. A variety of image formats are described here.

As it is an iterative process, you'll have to specify when you want to stop by the minimum percentage of binary points in the result image if you want to produce a binary image or by giving the value 0 to this parameter, then the program stops when the maximum entropy of the processed image is reached.

The parameter alpha is related to the speed of the process. Higher is alpha (I mean greater than 5), faster you'll get the result but with high alpha the local structure is some time not well taken into account. Default value is quite good for any kind of scenes.

As it is a multiresolution technique, you can also specify how many levels of the multiresolution pyramid you want to take into account. Higher is H, better is the result so ...

Warning: The process and file format conversions performed by this system can be rather time consuming... It might take a couple minutes for the result to be returned.

For more details on this technique in english or in french.

For comments or suggestions.

Jean-Michel JOLION (
Tel: (+33) 72 43 87 59
Fax: (+33) 72 43 80 97
Reconnaissance de Formes et Vision
INSA Lyon (Bat. J Verne (17 Av. Capelle))
20, Avenue Albert Einstein
Villeurbanne, 69621 cedex, FRANCE