Cost function to measure objective quality for sharpness enhancement functions

#1. Technical Field

#The present invention relates generally to sharpness enhancement of video images, and more specifically relates to a system and method of calculating a cost function to identify an optimal level of enhancement.

#2. Related Art

#These and other features of this invention will be more readily understood from the following detailed description of the various aspects of the invention taken in conjunction with the accompanying drawings in which:

#FIG. 1 depicts an enhancement system.

#FIG. 2 depicts an enhancement system in accordance with the present invention.

#1. Overview

#Described herein is a system and method for improving performance for a set of enhancement functions in a sharpness enhancement system. To achieve this, output quality is objectively measured and the gains associated with the individual enhancement functions are then modified such that the best quality is achieved. By analyzing the system output as opposed to the output of the individual functions, the problem of interdependencies is eliminated.

#FIG. 2 shows an exemplary diagram of a system 20 utilizing the proposed technique. In FIG. 2 an additional block is included, i.e., the picture quality analyzer 30, and instead of having just coefficients α and β, a set of candidate vectors (αi, βi) are included. As described below, present invention provides a system in which the coefficients α and β, which make up the enhancement vector, are not independently selected. Rather, the picture quality analyzer 30 selects the optimal enhancement vector (αopt, βopt) from the candidate set of vectors (αi, βi) based upon the output quality generated by each vector in the set. To achieve this, a cost function is utilized to determine which vector from the set of enhancement vectors should be used. Implementation of the cost function is described in detail below.