1. A method of operating a bar code reader which captures frames of image data, said method comprising: (A) defining a region of interest area in an initially captured frame of image data, said initially captured frame of image data including an M×N array of pixel values, said region of interest including an m×n, m<M, n<N array of pixel values, said region of interest area positioned at a center of said initially captured frame; (B) searching for a decodable symbol representation within said region of interest; (C) maintaining an original dimension of said region of interest area if in said searching step (a) a decodable symbol representation is located in said region of interest and (i) said decodable symbol representation located at step (ii) is determined to be positioned entirely within said region of interest; and (D) automatically expanding a dimension of said region of interest area if at step (B) it is determined that an entire decodable symbol representation is not located within said region of interest area.