An Intelligent Time Code Peripheral for Computer Based Video Tape Editing Systems

Author(s): Michael Racelo
Publisher: Society of Motion Picture and Television Engineers
Publication Date: 1 February 1983
Conference Location: San Francisco, CA, USA
Conference Date: 4 February 1983
Page(s): 223 - 232
ISBN (Paper): 978-1-61482-913-3
DOI: 10.5594/M00609



In 1969 SMPTE proposed a standard time code, now familiarly known as Longitudinal Time Code (LTC), which laid the foundation for computer based video tape editing systems. In the following year, the semiconductor industry introduced the first microprocessor chip. Eleven years later in 1981, SMPTE proposed a new time code standard called Vertical Interval Time Code (VITC) for high performance video tape editing systems, and this standard was adapted to PAL and SECAM systems by the European Broadcasting Union (EBU). At the same time, the semiconductor industry introduced a new generation of high performance microcomputer chips which far exceeded the capabilities of the earlier microprocessors. This paper reviews the differences between VITC and LTC, and discusses an intelligent time code peripheral, packaged in a single 1-3/4 inch rack-mounted chassis, which employs modern microcomputer technology to simultaneously generate and read both time codes for use in NTSC, PAL, and SECAM systems.