According to one embodiment, an image processing apparatus includes an image block generator, a pixel extractor, a correction parameter calculator and a corrector. The image block generator enlarges an image block including a plurality of pixels to generate an enlarged image block. The pixel extractor extracts a maximum pixel with a maximum pixel value and a minimum pixel with a minimum pixel value from the image block. The correction parameter calculator calculates a correction parameter including a first difference and a second difference. The first difference is an absolute value of a difference between a sample pixel value of a sample pixel to be corrected in the enlarged image block and the maximum pixel value. The second difference is an absolute value of a difference between the sample pixel value and the minimum pixel value. The corrector corrects the enlarged image block using the correction parameter.