An image processing apparatus which can determine the image quality of code data in consideration of the print characteristics of an output device (copying machine or printer) is provided. A code data input unit inputs code data to be added to an image. A print precision data input unit inputs print precision data indicating the print precision of the code data by a printing device. An image quality determination unit determines, based on the code data and the print precision data, the image quality when the printing device prints the code data.