As discussed in Colours from imported MP4 screencast video look dull in Blender, I recently stumbled across what I perceive to be an oddity with the new Filmic colour management: When working with imported 24bit images or video files (i.e. non-HDR) in the VSE and the colour management is set to Filmic, the colours in the output will not correspond to the input (see screenshots in question linked above).
This does not line up with how I thought Filmic works: My understanding so far was that (very simplified) it would scan the input for the maximum intensity and then scale everything down so that this maximum intensity becomes 1.0 (=pure white) - provided the input does contain intensities greater than 1. However, if I'm only working with 24bit input material, then this should never occur, shouldn't it? Or is Filmic not able to detect this limitation in the input material and always assumes a "buffer" on top of the 1.0 intensity?
To clarify: I already figured out how to get the desired output for the VSE (i.e. do not use Filmic). This question is exclusively about the Why of this solution.