A method and apparatus for ranking pixels in an image by degrees of
saliency, including: defining (200, 210) a plurality of regions for each
of a plurality of pixels in an image, where each of the regions for any
one of the pixels at coordinates (x,y) has a different scale s,
calculating (230) an entropy value for each of the regions, identifying
(260) any of the regions as having a peak entropy value, weighting (270)
the peak entropy value of each of the peak entropy regions by a weight
value corresponding to a peak width estimate of the peak entropy value,
and ranking (290) the regions by the weighted peak entropy values,
thereby ranking the pixels. The invention can be included in a method and
apparatus for image transmission, providing preferential transmission of
salient portions of the image.