摘要 |
PURPOSE:To detect the position of a straight-line boundary at high speed by a simple constitution including a counter and a memory by using that a luminance changes largely between neighboring horizontal synchronizing signals and a picture inflection point appears at the time of picture data in which the right and left luminance of a picture changes by the straight-line boundary. CONSTITUTION:When a starting signal St is added, a memory control circuit 4 clears the contents of the whole address of a memory 3 up to 0 and the circuit is made into an operating condition by the arrival of a vertical synchronizing signal Vs after that. After a counter 1 is reset by a horizontal synchronizing signal Hs, it counts the number of picture clock CK and makes a latch 2 latch it, now, when a boundary 5 in a up-down direction exists and an inflection point 6 exists in one horizontal scanning period between the neighboring horizontal synchronizing signal Hs, and edge signal Eg to show the inflection point 6 appears to a counter calculating value N1 and therefore, the circuit 4 adds 1 to the address N1 of the memory 3 and define the boundary. |