1. An apparatus that generates image data regarding an image region including a plurality of partial regions based on synchronization signals generated at a predetermined time interval, the apparatus comprising: a memory; a first processor coupled to the memory; and a second processor coupled to the first processor, wherein the first processor is configured to generate a first instruction, based on a first synchronization signal, the first instruction instructing that first partial image data regarding N (N is a natural number) partial regions of the plurality of partial regions are to be generated, the second processor is configured to generate the first partial image data based on the first instruction, the first processor is configured to determine a natural number M based on a time when the generation of the first partial image data is completed and a time when a second synchronization signal which is subsequently issued to the first synchronization signal is generated, and is configured to generate, based on the second synchronization signal, a second instruction instructing that second image data regarding M partial regions of the plurality of partial regions are to be generated, and the second processor is configured to generate the second partial image data based on the second instruction.