OBJECTIVE PICTURE QUALITY SCALE (PQS) FOR IMAGE-CODING

A new methodology for the determination of an objective metric for sti ll image coding is reported. This methodology is applied to obtain a p icture quality scale (PQS) for the coding of achromatic images over th e full range of image quality defined by the subjective mean opinion s core (MOS), This PQS takes into account the properties of visual perce ption for both global features and localized disturbances. PQS closely approximates the MOS, with a correlation coefficient of more than 0.9 2, as compared to 0.57 obtained using the conventional weighted mean-s quare error (WMSE). Extensions and applications of the methodology and of the resulting metric are discussed.