On Wed, 2021-09-15 at 17:01 +0300, Pekka Paalanen wrote: > On Fri, 30 Jul 2021 16:41:29 -0400 > Harry Wentland <harry.wentland@xxxxxxx> wrote: > > > Use the new DRM RFC doc section to capture the RFC previously only > > described in the cover letter at > > https://patchwork.freedesktop.org/series/89506/ > > > > v3: > > * Add sections on single-plane and multi-plane HDR > > * Describe approach to define HW details vs approach to define SW > > intentions > > * Link Jeremy Cline's excellent HDR summaries > > * Outline intention behind overly verbose doc > > * Describe FP16 use-case > > * Clean up links > > > > v2: create this doc > > > > v1: n/a > > > > Signed-off-by: Harry Wentland <harry.wentland@xxxxxxx> > > Hi Harry, > > I finally managed to go through this, comments below. Excellent to > have > pictures included. I wrote this reply over several days, sorry if > it's > not quite coherent. > > > > <snip> > > + > > + > > +Overview and background > > +======================= > > + > > +I highly recommend you read `Jeremy Cline's HDR primer`_ > > + > > +Jeremy Cline did a much better job describing this. I highly > > recommend > > +you read it at [1]: > > + > > +.. _Jeremy Cline's HDR primer: > > https://www.jcline.org/blog/fedora/graphics/hdr/2021/05/07/hdr-in-linux-p1.html > > That's a nice write-up I didn't know about, thanks. > > I just wish such write-ups would be somehow peer-reviewed for > correctness and curated for proper referencing. Perhaps like we > develop > code: at least some initial peer review and then fixes when anyone > notices something to improve. Like... what you are doing here! :-) > > The post is perhaps a bit too narrow with OETF/EOTF terms, > accidentally > implying that OETF = EOTF^-1 which is not generally true, but that > all > depends on which O-to-E or E-to-O functions one is talking about. > Particularly there is a difference between functions used for signal > compression which needs an exact matching inverse function, and > functions containing tone-mapping and artistic effects that when > concatenated result in the (non-identity) OOTF. > > Nothing in the post seems to disagree with my current understanding > FWI'mW. I'm more than happy to update things that are incorrect or mis-leading since the last thing I want to do is muddy the waters. Personally, I would much prefer that any useful content from it be peer-reviewed and included directly in the documentation since, well, it's being hosted out of my laundry room and the cats have a habit of turning off the UPS... Do let me know if I can be of any assistance there; I'm no longer employed to do anything HDR-related, but I do like clear documentation so I could dedicate a bit of free time to it. - Jeremy
