Region based segmentation¶

Because edge based segmentation leave contours not closed, one may be interested in searching for regions.

Region growing¶

Starting from one point of the “object” region and recruiting neighbouring pixels.

Split and merge¶

split phase¶

one define an homogeneity function

recursive image split:

• if image is homogeneous
  • return
• else
  • split the image into 4 and apply the test on each sub-image

merge phase¶

• for each adjacent sub-image
  • if the two grouped regions satisfies the homogeneity criterion, merge the regions

see also:

• Split and merge DIP p.461

the watershed transform¶

see also:

• watershed in the mathematical morphology section