According to one embodiment, there is provided an analog gain range determining unit that determines a range to which an analog gain setting an amplification factor of a pixel signal read from a pixel belongs, a clamp parameter control condition setting unit that sets a control condition of a clamp parameter setting the black level based on a result of the determination by the analog gain range determining unit, and a clamp parameter control unit that controls the clamp parameter based on the control condition set by the clamp parameter control condition setting unit.