1. A method comprising: identifying font-based barcode elements to encode a value, the font-based barcode elements describing a block barcode; determining whether image data and associated graphical elements are available for the block barcode by accessing a style sheet containing tested image data and associated graphical elements; when the image data and the associated graphical elements are available, dynamically modifying the font-based barcode elements to produce a modified barcode that conveys an image based on the image data other than a block barcode; and printing the modified barcode.