Transmission rate reduction in monitoring two-dimensional moving images in factory automation

This paper describes transmission rate reduction accomplished on the basis of the subjective evaluation of images in the NTSC system when two-dimensional moving images are being monitored in factory automation. A new transmission system has been proposed on the basis of the subjective evaluation, and the transmission rate has been reduced by processing a two-dimensional moving image using more simple and inexpensive digital NTSC picture encoding and decoding circuits than those for MPEG2. Utilizing the proposed transmission system, the viewer can watch and process digital image data on line in a location far from the camera built in a machine. In addition, the proposed system transmits camera shots at a reduced transmission rate utilizing both edge-emitting LEDs (ELEDs) and single-mode (SM) optical fibers of up to 10 km in length without any repeaters. As an application to factory automation, the proposed system could satisfactorily transmit a moving image of a cutting tool tip in the laser cutting machine cutting a metal plate