Patent ID: 7502518
Filing Date: 2009-03-10
Classification: H04N

Abstract:
1. An apparatus for coding an image, comprising: a setting unit that sets a quantization width for each coded block of an image frame of image data; a visual attention calculating unit that calculates for each coded block a level of visual attention for a first element, the level of visual attention taking a value in a range between a maximum value and a minimum value thereof in the image frame; a perceptual distortion calculating unit that calculates for each coded block a level of perceptual distortion for a second element whose distorted image quality is easily visually perceived, the level of perceptual distortion taking a value in a range between a maximum value and a minimum value thereof in the image frame; a correcting unit that corrects the quantization width to a value obtained as a result of a multiplication in which a product of the level of visual attention and the level of distorted precision is multiplied by the quantization width set by the setting unit; and a quantizing unit that quantizes the image data based on the corrected quantization width.