Abstract: In order to compensate for some limitations of the existed clarity evaluation function(CEF) of the image definition, a total bounded variation (TBV) of image is studied. It is proved that there is some relationships between the TVB of image and the digital image definition. Furthermore, the clearer image from image restoration process can be acquired when the criterion based on TVB of the image is used. Finally, the computer simulation is provided for the validation of the relation obtained.

Key words: image definition, evalution funtion, image restoration, total bounded variation