EBU colour bars

The EBU colour bars are a television test card used to check if a video signal has been altered by recording or transmission, and what adjustments must be made to bring it back to specification.

It is also used for setting a television monitor or receiver to reproduce chrominance and luminance information correctly.

The EBU bars are most commonly shown arranged side-by-side in a vertical manner (as in the images in this article), though some broadcasters – such as TVP[1] in Poland, and Gabon Télévision[2] in Gabon – were known to have aired a horizontal version of the EBU bars.

It is similar to the SMPTE color bars, although that pattern is typically associated with the NTSC analogue colour TV system.

Many test cards, such as Philips PM5544 or Telefunken FuBK, feature elements equivalent to the EBU colour bars.

EBU colour bar values for standard-definition television systems following BT.601, as specified in ITU-R Rec.

components according to BT.601 is as follows:[10] EBU colour bar values for high definition TV systems following BT.709, as specified in ITU-R Rec.

[11] This pattern allows testing of UHDTV to HDTV conversion, measuring luminance response, saturation and hue shifts, and checking near‑black performance.

It can also be used to check for correct hardware settings, transmission chain errors, and proper colour space transforms from ITU‑R BT.2100 HLG to ITU‑R BT.709.

[14] Another similar pattern named Colour Bar Test Pattern for Hybrid Log-Gamma (HLG) High Dynamic Range Television (HDR-TV) System was developed by ARIB in 2018 (ARIB STD-B72), based on the SMPTE color bars commonly used in Japan and United States.