Both the DSC in [[DisplayPort]] and the default settings of [[JPEG XL]]<ref>{{man|1|cjxl|ManKier}}</ref> are regarded as ''visually lossless''. The losslessness is usually determined by a ''flicker'' test: the display initially shows the compressed and the original side-by-side, switches them around for a tiny fraction of a second and then goes back to the original. This test is more sensitive than a side-by-side comparison ("visually almost lossless"), as the human eye is highly sensitive to temporal changes in light.<ref>{{cite book |author-link=ISO/IEC JTC 1/SC 29 |author=ISO/IEC JTC 1/SC 29 |title=ISO/IEC 29170-2:2015 Information technology — Advanced image coding and evaluation — Part 2: Evaluation procedure for nearly lossless coding|url=https://www.iso.org/standard/66094.html |url-access=subscription |chapter=Annex B. Forced choice paradigm with interleaved images test protocol|websitepublisher=ISOInternational Organization for Standardization |language=en}}</ref> There is also a ''panning'' test that is purportedly more sensitiverepresentative of sensitivity in the case of moving images than the ''flicker'' test.<ref>{{cite conference |author1=Allison, Robert |author2=Wilcox, Laurie |author3=Wang, Wei |author4=Hoffman, David |author5=Hou, Yuqian |author6=Goel, James |author7=Deas, Lesley |author8=Stolitzka, Dale |conference=The Society for Information Display's annual Display Week 2017 |title=Large Scale Subjective Evaluation of Display Stream Compression |url=https://www.researchgate.net/publication/317425815}}</ref>