Qualitative aspects of image applications in multimedia technology

Dramatic progress in multimedia technology within the last decade has brought numerous problems and questions related to the image quality assessment and evaluation. All blocks of imaging chain have an impact on the final image quality perceived by an observer-optical imaging system, sensing, source coding and compression, channel coding and transmission, retrieving, displaying incl. printing etc. Therefore the study of image qualitative parameters is crucial at the recent development period of multimedia applied systems. The paper describes and summarizes the impacts of all relevant blocks: Optical Imaging System-description, parameters, Image Sensors and Displays-2D sampling and 2D aperture, colorimetric aspects, Source Image Compression-lossless and lossy techniques, distortions and artifacts, Methodology of Subjective Quality Tests, Objective Quality Criteria, Modeling of HVS, Subjective Image Quality Enhancement. Selected experimental image quality evaluation results based upon our activities under two research projects of the Czech Grant Agency and two research projects of the Ministry of Education are finally presented.