A print processor is disclosed which comprises: an input unit for inputting print data including at least either texts or graphics and described in predetermined drawing instructions; an image output unit for outputting images based on data having a predetermined data structure; an intermediate data generating unit for generating intermediate data from the print data, the intermediate data being expressed in a format which is higher in abstract terms than the data structure and which includes at least one basic graphic; an rasterizing process unit for rasterizing the intermediate data into the data structure and for supplying the image output unit with the intermediate data thus rasterized; a determining unit for determining a number and a size of the basic graphics constituting the intermediate data generated by the intermediate data generating unit; an rasterizing time predicting unit for predicting the time it takes the rasterizing process unit to rasterize the intermediate data on the basis of the number and the size of the basic graphics determined by the determining unit; and a control unit for determining an image output speed of the image output unit in accordance with the time predicted by the rasterizing time predicting unit.