Patent ID: 7702175

Claim:
An image processing apparatus receiving an input image signal and performing an enhancement process on a high frequency component included in the input image signal based on a low frequency component of the input image signal, the image processing apparatus comprising: a combined wave component generator which comprises a Finite Impulse Response (FIR) filter, wherein the FIR filter extracts a first brightness value, a second brightness value, and a third brightness value from the input image signal at respective predetermined cycles, multiplies the first, second, and third brightness values by respective predetermined mixture coefficients, and adds the multiplied results together to output a combined wave component, the FIR filter comprising: a slope detector which detects a first slope value between the first and second brightness values and a second slope value between the second and third brightness values; and a mixture coefficient controller which controls a ratio of the mixture coefficients of the first and third brightness values such that after comparing the first slope value with the second slope value, the mixture ratio of the brightness values on the side of having a more gradual slope value is increased and the mixture ratio of the brightness values on the side of having a steeper slope value is decreased; and an enhancement processor which performs an enhancement process on the high frequency component obtained by removing the combined wave component from the input image signal.