The good intentions of IEEE standard 1180, may it rest in peace

Kenneth R. Vollmar, Missouri State University


The 8x8 IDCT (Inverse Discrete Cosine Transform) is an integral component of many standard digital image and video compression schemes, including JPEG baseline and the MPEG family of standards. A statistically-oriented standard, ANSI/IEEE 1180-1990, specifies the accuracy for a compliant 8x8 IDCT. ANSI/IEEE 1180-1990 has a checkered history, including being twice administratively withdrawn, notwithstanding that the standard has continuously been referenced by the MPEG family of standards. The standard was withdrawn for the second time in February 2003 and is not currently supported by either ANSI or IEEE. In response to the withdrawal of the standard, the MPEG family has initiated procedures to replace the reference with self-contained wording. This paper examines the intent and some implications of the now-withdrawn ANSI/IEEE 1180-1990 IDCT standard.