A method on a computing device for categorizing one or more blocks of an image is disclosed. The method includes computing a membership value of each of the one or more blocks for each of one or more categories based on a set of parameters associated with each of the one or more blocks. The one or more categories comprise at least an image category. Each of the one or more blocks is categorized in the one or more categories based on the membership value. A category of at least one block is modified to the image category based on a reference signal and the membership value such that the number of blocks categorized under the image category increases.