| 摘要 |
PURPOSE:To evaluate objectively the propriety of a television receiver to be checked, by detecting quantitatively the strength of beat components. CONSTITUTION:A video signal including the beat component is differentiated at a differentiating circuit 2, converted into a digital signal at an A/D conversion circuit 3, and then inputted to a comparator 5, where the signal is compared with a reference value. A pulse from the comparator 5 is applied to a counter 6. Every time the pulse is applied from the comparator 5 to the counter 6, a corresponding address of a projecting memory 7 is incremented and the distribution of the number of picture elements including the beat components at each area sectioned in the unit of the picture elements in the direction of horizontal scanning is obtained at the projecting memory 7 at one field or one frame period. This distribution is read in a processor 9 via a multiplexer 8 and processed to discriminate the intensity of the beat component. |
