According to embodiments, an image processing apparatus includes an image signal holding unit. The image processing apparatus uses an image signal passing through the common image signal holding unit to generate first, second and third correction values. The first correction value is a signal value applied to a pixel in which saturation of an output occurs in a saturation determination. The second correction value is a signal value subjected to a noise cancellation process. The third correction value is a signal value applied to a pixel in which defect occurs in a defect determination.