Automatic image evaluation process

摘要

The picture video signal from the camera is converted by the analogue-digital converter (6) into a sequence of digital data words. They are stored at successive addresses in a memory (10) connected by a bus system (9) to the microcomputer (8), managed by a video control unit (7). The picture memories (10, 11, 12) store the contrast mask and difference pictures, so that a difference picture can be produced. A histogram of the image values is created from the difference image section. If the image sections agree, the difference image section would show a frequency maximum for image value zero ie a constant image.