Biomedical Imaging Group
EPFL   Imaging Web Demonstrations
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This demonstration shows the segmentation of images by the watershed algorithm. The implementation is based on the immersion process analogy, using the gray levels as a topological relief.
The objects to be separated should be dark, i.e. low gray values.
We recommend smoothing the image in order to avoid over segmentation.
NEW : You can upload your own image into the applet.
Choose your image file and click on the button "Start the Applet Demonstration".
The applet accepts GIF or JPEG 256*256 pixels image (max size 1 Mb).

Instruction to use the applet
  1. Choose an input image in the list.
  2. Choose a sigma to smooth the image
  3. Press on "Smoothing".
  4. Press on "Watershed".
Toolbar in the image display
pointer_on Get the coordinates and value of a pixel.
info_on Get the maximum, minimum and the mean value of the image.
frame Open a new window containing the image.
zoomin_on Zoom out by a factor 2.
(N/A on Netscape)
zoomout_on Zoom in by a factor 2. (N/A on Netscape)
move Move the zoomed part of the image. (N/A on Netscape)