1. An image processing apparatus used for displaying an image obtained from an inputted image signal on an image display, the image processing apparatus comprising: an attribute information determining unit which obtains first attribute information indicating the format of the inputted image signal and second attribute information indicating transmission characteristics of the image signal; an image quality adjustment value calculating unit which calculates image quality adjustment values for the image signal based on the first and second attribute information obtained by the attribute information determining unit; and an image processing unit which adjusts the image quality of the image signal based on the image quality adjustment values calculated by the image quality adjustment value calculating unit and then outputs the image to the image display.