| 摘要 |
PURPOSE:To shorten the computing time of the peripheral length of an isolated object by obtaining the difference between the total area of an image of the object within a binary image and the partial area with peripheral pixels removed from the image of the object. CONSTITUTION:A binary image data B is inputted in time sequence synchronously with a clock signal CLK. In a data synchronizing circuit 1, data of both an optional pixel and a predetermined number of pixels adjacent to the optional pixel is outputted in time sequence for the whole of the binary image by line delay circuits 11, 12 each of which makes one line delay to the data B in a horizontal or vertical direction, and latch circuits 13-16 each of which gives a delay of one pixel. A partial area computing circuit 2 counts clocks synchronous with the data B only when the data outputted from the circuit 1 are all in the high level, and counts the remaining number of pixels left after the peripheral pixels are removed from the image of the isolated object. On the other hand, a total area computing circuit 3 counts clocks only when the data B is high, so that the total number of pixels of the image of the isolated object is counted. A subtracter circuit 4 subtracts the outputted value of the circuit 2 from that of the circuit 3. Accordingly, the peripheral length of the object present in the data B can be known. |
