| 摘要 |
PURPOSE:To provide a horizontal direction compression/expansion circuit which can be manufactured by low cost in a horizontal direction compression/ expansion circuit capable of displaying video signals by various kinds of screen sizes on a long sideways display having an aspect ratio of 16 to 9, etc. CONSTITUTION:The inside of line memories 1, 2 are divided into two areas, respectively, a writing operation is made to perform for the one area by a writing control circuit 3 and a reading operation is made to perform from the other area by a reading control circuit 4 at the same time of the writing operation for a prescribed period. The writing is performed for line memories 1 and 2 alternately at every other data and the reading is also performed for the line memories 1 and 2 alternately at every other data. Thus, a compression/ expansion operation is available by a low read cycle and a write and a low-cost line memory can be used. |
