An improved detection model for DCT coefficient quantization

Abstract

A detection model is developed to predict visibility thresholds for discrete cosine transform coefficient quantization error, based on the luminance and chrominance of the error. The model is an extension of a previously proposed luminance-based model, and is based on new experimental data. In addition to the luminance-only predictions of the previous model, the new model predicts the detectability of quantization error in color space directions in which chrominance error plays a major role. This more complete model allows DCT coefficient quantization matrices to be designed for display conditions other than those of the experimental measurements: other display luminances, other veiling luminances, other spatial frequencies (different pixel sizes, viewing distances, and aspect ratios), and other color directions.