Mohamed H. Development of methods of evaluation image distortions in the video paths of digital television

An object is a process of measurement of descriptions of video paths of standard and high definition systems. An objective is a development of methods of evaluation of image distortions with use of test signals and test images for measurement of standard definition and high definition video paths characteristics. Research methods: methods of mathematical description of signals in the systems with the digital encoding, spectral analysis, theory of the generalized functions. Theoretical and practical results: classification of corresponding types of distortions, evaluation methods and test signals. The generalized analysis of test patterns for the evaluation of image distortions in two dimensions in the digital TV system light-to-light video path and of principles of use of metadata for control and monitoring of digital television systems video paths characteristics organization. The mathematical models of test signals set description which is based on the use of Blackman window function are built. The parameters of signals are offered for the standard and high defenition systems with the arbitrary bit depth. Description of ideal saw-tooth signal components is built taking into account filtration, allowing to avoid measurement results distortions due to Nyquist theorem terms non-fulfillment. The estimation of sensitiveness of color bar signals and other test patterns is given to interference and distortions in the high-frequency area of spectrum of these signals. The alternative variants of construction of the standard color bars are offered taking into account possibility of change of their angle of slope in relation to an image. The criterion of evaluation of image distortions in two dimensions on the color bar signals based on the use of evaluation of distortions on different directions is offered. The approach based on realization of brightness and colour transitions with the small angles of slope relatively horizontal and vertical directions is generalized for case of color bars signals use. Lifted restrictions in relation to the use of signals frequency of the fields for the standard definition digital television systems, specified in Recommendation ITU-R BT.801-1, and the use of these signals is offered for the high definition progressive, interlaced and segmented frame systems. Scientific novelty: the methods of estimation of distortions in the digital television system video paths with use of test signals and teat images are improved. The analysis of test patters for evaluation of distortions of image in two dimensions in the light-to-light digital TV systems path is first executed and suggestions are brought in on their perfection. The mathematical models of test patterns set with the use of Blackman window function are first built. The evaluation of sensitiveness of color bar signals and other test signals to the interference and distortions in the high-frequency area of spectrum of these signals is first given. The criterion of image distortions evaluation on different directions in two measurements on the signals of the color bars is first offered. The results of studies are implemented in such organizations: the Odessa National Academy of Telecommunications n.a. A.S. Popov, State Enterprise “ the Ukrainian Scientific Research Institute of Radio and Television ”, offered for the use in the educational process of the Academy and in international standardization.