By Bronwen Lindsay Jones, Independent Contractor, Richard S. Prodan, Ph.D., Cable Television Laboratories, Inc. and David A. Eng, Cable Television Laboratories, Inc
An experimental design incorporating psychophysical test methods for use in the subjective assessment of picture-quality variations due to compression artifacts is described. Standard-definition television pictures are used as test material, including video, film and some extensively utilized MPEG (Moving Picture Experts Group) test sequences. This study is unique and may be the first of its kind. The effect of compression artifacts on picture quality is very subtle in nature. There are many trade-offs between and among bit rate, compression tools, resolution, picture content and recording format. A combination of test methods is being utilized, based in part on a new International Telecommunications Union-Radiocommunication Sector ( ITU-R) listening test procedure for testing very small differences.