ISO 9642:1993

Specifies digital code formats and modulation methods for motion-picture film to be used for timing, control, editing and synchronization purposes. Also specifies the relationship of the codes to the motion-picture frame. Two types of code are described: type C (a continuous code very similar to the continuous code specified in IEC 461) for film moving continuously at the time of both recording and reproduction, and type B (a non-continuous, block-type code, composed of blocks of data with gaps between the blocks) for intermittent film motion.