METHOD OF REMOVING DISTORTIONS FROM DIGITAL IMAGES Russian patent published in 2010 - IPC G06K9/40 

FIELD: information technology.

SUBSTANCE: size of coding unit relative the required printer resolution is evaluated. If the size of the unit is discernible by the human eye, the following steps are carried out: the approximate metric of discernibility of a distortion caused by the Gibbs effect is determined for each coding unit and stored in memory; the approximate metric of discernibility of block distortion is determined for each border of the unit; if the corresponding element of the approximate metric of discernibility of unit distortion exceeds a predefined threshold value, a filter which can suppress block distortions is applied to the given border of the unit; for each coding unit, if the corresponding element of the approximate metric of discernibility of distortion caused by the Gibbs effect exceeds a predefined threshold value, a filter which can suppress distortions is applied to the coding unit in order to suppress distortions caused by the Gibbs effect.

EFFECT: preservation of image sharpness.

7 cl, 6 dwg