Predictive coding device for video signal

Abstract

Abstract PURPOSE: To secure the automatic correction in an extremely small time for deterioration of the video signal caused by the undesired signals by adding a small number of circuits in case some error takes place under the process or in the transmission. CONSTITUTION: The value corresponding to the fixed picture element, which is designated by controller 33 among the picture signals applied to input terminal 24, is memorized in memory 32. And the delay of one horizontal scanning period is given to the output signal of the predictive error in quantizer 26 via delay unit 27. The output of unit 27 and memory 32 are applied to switch 28, and the output of unit 27 is always selected by the command of controller 33. Then the output of memory 32 is selected in the fixed timing of the blanking time to be supplied to transmission line 34. At the same time, the output of line 34 is applied to quantization adverse converter 36 or one side of memory 40 via switch 35 controlled by controller 39, and the picture element of memory 32 is memorized in memory 40. Then the comparison is given at subtractor 41 between the picture element of memory 40 and output terminal 38, and the differential is held at holding unit 43. In such way, the deterioration of the video signal caused by the undesired signals can be corrected automatically and in an extremely small time. COPYRIGHT: (C)1980,JPO&Japio

Inventors

• 👤 Akifumi Ide

Bibliographic Details