The automatic extraction of features from images is then called to tag the scene in a manner which is close to the human perception of it. For example, image features might include landscape at dusk or broad day time, human or animal interactions, textured image and so on. To this purpose, computer vision algorithms need first to extract salient features of the image and then cluster them according to semantically meaningful groups. Region-growing techniques are utilize to subdivide the image into non-overlapping regions containing salient features. The edge map of the image (in all color channels) is used to determine stiff boundaries for region growing and peaks of the edge distance-transform are used as initial seeds for the process.