Looks a bit like these video grading tools: https://digitalfilms.files.wordpress.com/2015/06/df2215_resolvetips_main.jpg https://digitalfilms.files.wordpress.co

Looks a bit like these video grading tools: https://digitalfilms.files.wordpress.com/2015/06/df2215_resolvetips_main.jpg https://digitalfilms.files.wordpress.com/2015/06/df2215_reso... (but I never understood what they actually show) edit: ahhh, it encodes x position, but luminance distribution on y https://youtu.be/0ghTPnf89ME?t=166 https://youtu.be/0ghTPnf89ME?t=166