PQ (Perceptual Quantizer)
A high-dynamic-range (HDR) transfer function that relates image signal values to absolute light levels produced by a display. PQ is standardized in SMPTE ST 2084 and is one of the two supported transfer functions in the ITU-R Rec. 2100 standard for HDR video. PQ is used in formats such as HDR10, HDR10+, and Dolby Vision.