1. An image processing apparatus comprising: a communication unit configured to communicate with an external apparatus; an expanded image judging unit configured to judge whether an image to be drawn in response to a request that is received from the external apparatus by the communication unit is an expanded image of a 1-line source image; an image expansion direction judging unit configured to judge whether an expansion direction of the expanded image of the 1-line source image is parallel with a band extending direction when the expanded image judging unit judges that the image to be drawn is the expanded image of the 1-line source image; a drawing data processing unit configured to analyze the 1-line source image and converts the expanded image of the 1-line source image into vectors that are a series of rectangular regions of sane-color pixels that are arranged continuously when the image expansion direction judging unit judges that the expansion direction of the expanded image of the 1-line source image is parallel with the band extending direction; and a drawing processing unit configured to generate a bit map of a destination image to be drawn on a basis of the expanded image as converted into the vectors by the drawing data processing unit, wherein intermediate codes are: generated by dividing a drawing image into prescribed bands extending in one direction, developed into a bit image, and drawn as the bit image.