The SMPTE Color Bars is a trademarked television test pattern used where the NTSC video standard is utilized, including countries in North America. The Society of Motion Picture and Television Engineers (SMPTE) refers to this test pattern as Engineering Guideline EG 1-1990. The components of this pattern are a known standard. Comparing this pattern as received to the known standard gives video engineers an indication of how an NTSC video signal has been altered by recording or transmission and what adjustments must be made to bring it back to specification. The pattern is also used for setting a television monitor or receiver to reproduce NTSC chrominance and luminance information correctly. The color bar test pattern was originally conceived by Norbert D. Larky and David D. Holmes of RCA Laboratories and first published in RCA Licensee Bulletin LB-819 on February 7, 1951. U.S. patent 2,742,525 Color Test Pattern Generator was awarded on April 17, 1956 to Norbert D. Larky and David D. Holmes. Previously categorized by SMPTE as ECR 1-1978, the development of this test pattern was awarded an Engineering Emmy in 2001-2002.
An extended version of SMPTE Color Bars signal, developed by the Japanese Association of Radio Industry and Businesses as ARIB STD-B28 and standardized as SMPTE RP 219:2002 (High- Definition, Standard- Definition Compatible Color Bar Signal) was introduced to test HDTV signal with an aspect ratio of 16:9 that can be down converted to a SDTV color bar signal with an aspect ratio of either 4:3 or 16:9. The Color Bar signal is generated with unconventionally slow rise and fall time value to facilitate video level control and monitor color adjustments of HDTV and SDTV equipment.
