The data processor enhances the bus throughput or data throughput of an external memory, when there are frequent continuous reads with a smaller data size than the data bus width of the external memory. A sound image localization processing filter section performs a sound image localization process on the low-frequency-component acoustic signal. The zoom-lens module generates an enlarged image of the defect, and displays the enlarged image simultaneously with the layout image. Finally, for each time interval, the position of the front is reconstructed by means of a fast Fourier transform and injection of the sweeping fluid is optimized according to the position of said front. If the thread associated with the interrupt has a higher priority than the previously received packet, the thread associated with the previously received packet is saved in a Shared Arena storage area.