An image processing apparatus 200 includes: a first saturation information obtaining unit 306 configured to obtain saturation of a frame image; a second saturation information obtaining unit 309 configured to obtain saturation of a background image; and a threshold value determining unit 311 configured to determine a threshold value, which is used for checking a difference in color information, for each pixel, based on the saturation obtained by each of the first saturation information obtaining unit 306 and the second saturation information obtaining unit 309. A hue foreground area estimating unit 312 is configured to estimate a foreground area by use of the threshold value determined by the threshold value determining unit 311 as well as color information of the frame image and color information of the background image.