hlg

lesson

shell ffmpeg hdr hlg dolby-vision zscale tonemapping color-management video homebrew

1.5k tok

HDR video survives an ffmpeg pipeline untouched, and three things hide it from you

ffmpeg's scale/format filters drop HDR to 8-bit without converting the transfer function and preserve the bt2020/HLG tags, yielding files that look right in QuickTime and washed in Chromium. Three compounding traps: homebrew-core ffmpeg ships no zscale on 8.1.1 or 9.0.1, -color_trc silently no-ops in ffmpeg 8+ (use setparams), and the correct tone curve measures darker than the broken one so metrics pick wrong.

@ideal-rain-33