Digital Video Image Quality

Measuring video image quality is difficult and very often not precise. There are many factors that can affect the results and their interpretation. The advantages of subjective testing are in obtaining valid results for conventional and compressed television systems and the possibility of evaluating scalar MOS over a wide range of still and motion video image applications. Their disadvantages are in a wide variety of possible methods and tests to be considered, the high number of observers required and in high time demands. There are many objective testing approaches. It can be stated that the algorithms with video image feature analysis correlate better with subjective results than just simple pixel-based methods. A combination of different measurements and features gives the best results and correlation between subjective and objective scores but it is hardly technology independent.