Patent ID: 8224081

Claim:
An image processor comprising: a luminance signal processing unit processing a luminance signal; and a chrominance signal processing unit processing a chrominance signal, the image processor processing an image in which there are a smaller number of chrominance signals than luminance signals within a row of a pixel plane, the luminance signal processing unit including: a frequency transform unit performing frequency transform; a pre-filter performing prefiltering with a region which overlaps with plural unit regions for processing by the frequency transform unit as a unit region for processing, before frequency transform is performed; and a signal input unit receiving input of a luminance signal from outside the luminance signal processing unit and inputting a luminance signal to be processed by the pre-filter to the pre-filter, the signal input unit including a memory unit, wherein in a first input step from outside to the image processor, the signal input unit inputs to the pre-filter a first part of first luminance signals inputted from outside, the first part being a part to be processed by the pre-filter in the first input step, while storing a remaining second part of the first luminance signals in the memory unit, and in a second input step following the first input step, the signal input unit inputs to the pre-filter the second part of the first luminance signals read from the memory unit and a first part of second luminance signals inputted from outside, the first part being a part to be processed by the pre-filter in the second input step, while storing a remaining second part of the second luminance signals in the memory unit.