Real-time scheme of online measurement of screw-thread steel bars

In this paper we proposed a scheme of on-line measurement of screw-thread steel bar in real-time, which its operation principle is discussed in detail. With the aid of real-time, we have taken the following procedures: 1) By means of self- adjusting threshold voltage-level, the binary image is obtained through hardware. 2) By using run-length coding, the binary image is compressed furthermore and the sum of data to be processed is greatly reduced. 3) A special organization of the coding data, as well as a flexible employment of a novel dual-port RAM, make the CPU of computer capable of reading and saving the data directly from the storage buffer.