Image output apparatus and control method therefor

A control method for an image output apparatus which generates image data by rasterizing a series of object data, sorted in a band unit by analyzing print data, and outputs the image data as an image from image output means, said method comprising:

• a generating step of preparatorily generating image data by rasterizing the object data in the band unit;
• a measuring step of measuring a necessary time for image generation for a band in said generating step;
• and
• a control step of controlling the image output means to perform print processing with the image data generated preparatorily in said generating step, or controlling the image output means to generate image data by rasterizing the object data again, in accordance with the necessary time measured in said measuring step.

A storage medium storing a program with control program codes for an image output apparatus which generates image data by rasterizing a series of object data, sorted in a band unit by analyzing print data, and outputs the image data as an image from image output means, the program comprising:

• generation process codes for preparatorily generating image data by rasterizing the object data in the band unit;
• measuring process codes for measuring a necessary time for generating image data for a band in said generation process;
• and
• control process codes for controlling the image output means to perform print processing with the image data generated preparatorily in said generation process, or controlling the image output means to generate image data by rasterizing the object data again, in accordance with the necessary time measured in said measuring process.

A printer comprising:

• memory that stores a program list including a series of object data sorted in a band unit by analyzing print data;
• an image generator that generates image data by rasterizing the object data in the band unit and stores the image data in a band memory;
• a printing engine that prints an image, represented by the image data inputted from the band memory, on a medium;
• a time measuring unit that obtains a necessary time for generating the image data for a band by the image generator, as a cumulative value of a clock signal;
• and
• a controller that controls said printing engine to perform printing of the image data stored in the band memory, or controls said image generator to generate image data by rasterizing the object data again, in accordance with the necessary time.