This paper describes a hardware system design for a digitizer and an image processing logic (binary image planes & logic parts) of an automatic white blood cell differential counting system.
For the digitization of the white blood cell images, this system uses the color TV camera to obtain the electrical image signal from the optical image. In separation of a white blood cell from the blood sample image that contains a white blood cell and several red blood cells, the color information, especially blue, is useful.
This system uses two kinds of image data; one is the gray level image and the other is the blue-filtered image.
The digitizer is designed for the digitization of the image signal in either the hexagonal pattern or the square pattern, but this system uses the hexagonal pattern sampled image because of the use of Golay logic processor (GLOPR).
The 8-bit A/D converters (TDC 1007J) digitize the Y signal (gray level) and the B signal (blue) at high speed. One image plane has 64 × 64 pixels (pixel = picture element), that is, 4096 pixels. One pixel has 8-bit data, so that one image plane needs 4K bytes of RAM. So 8K bytes of RAM are needed to save the two multilevel images (Y, B).
This multilevel image (8 bits/pixel) is coverted to the binary image (1 bit/pixel) by a variable-thresh-olding logic.
This system uses the serial-parallel processing method to speed up the image process. The main logic operating parts of the system are the binary image planes and the logic parts that consist of six binary image planes (1 BIP = 64 × 63 pixels = 4K bits), 21 Golay logic processors and control parts.
Z-2 microcomputer system is used as a host computer and controls the system.