US Patent 7760394 Shading compensation circuit and control method thereof

A shading compensation circuit is provided which is capable of storing correction coefficients for shading compensation having optimal bit lengths, so that the data size of the correction coefficients can be reduced. The shading compensation circuit 10 for correcting the shading properties with respect to a horizontal direction and a vertical direction, has horizontal correction coefficient HHK and vertical correction coefficient VHK each having a bit length optimized according to a horizontal direction counter value HCT or a vertical direction counter value VCT. The horizontal and vertical correction coefficients HHK, VHK for the periphery of the image data are longer in bit length than the correction coefficients HHK, VHK for the center of the image data.