- From: Chris Lilley <chris@w3.org>
- Date: Tue, 17 Sep 2019 15:02:35 +0900
- To: Leonard Rosenthol <lrosenth@adobe.com>, "public-colorweb@w3.org" <public-colorweb@w3.org>
Hi Leonard, On 2019-09-16 18:36, Leonard Rosenthol wrote: > Chris - will there be a call in ability for the CG meeting? I had hoped to be in Japan for the meeting, but something came up...but as these topics are important, I want to be sure to participate. Unfortunately no, there are no call-in facilities for the Community Group meetings. > On item #3 (Image formats), other than "supporting stills from a movie or HDR photography", are there any requirements for this format? Also, do you (or anyone) have any proposals/recommendations? Of the few that I have seen, there does not appear to be consensus amongst implementors... > > Thanks, > Leonard > > On 9/16/19, 2:27 PM, "Chris Lilley" <chris@w3.org> wrote: > > I had hoped that the ICC white paper on HDR with ICC would be available > for discussion by this community group. Alas, that document does not yet > have consensus within ICC so has not yet been published. Once it is, I > will send a link to this CG for discussion. > > Topics which would be particularly useful to discuss: > > * Working Colorspace in CSS Color 4 > > For Web compat, things like compositing, gradients, anti-aliasing, and > general color interpolation defaults to sRGB. This is not a linear > space, so the results of computations are wrong. A new CSS property, > working-colorspace, would allow this to be altered. This is particularly > needed if any element is in a wider gamut colorspace. > > There have been various suggestions for suitable values. XYZ would > clearly work and would not clip. linear sRGB with headroom and footroom > to represent out of gamut colors would also work. > > * HDR and the Web, compositing SDR with HDR > > Typical use cases include showing some information (subtitles, actor bio > as a Web page) composited on top of HDR video. HDR (at least in PQ > encoding) uses absolute luminance, so where should sRGB white be placed? > Clearly not at 80 nits, clearly not at 4000 nits or whatever the display > is capable of for small hilights, and probably not at 1200 nts or > whatever full-screen value the display is capable of. How should that > work with HLG? What is the influence of scene metadata on this compositing? > > * Image formats for HDR > > Still images, such as stills from a movie or HDR photography, need to be > displayed on the Web. Ideally, W3C would not develop a new format but > use an existing, open, widely implementable one. > > -- > Chris Lilley > @svgeesus > Technical Director @ W3C > W3C Strategy Team, Core Web Design > W3C Architecture & Technology Team, Core Web & Media > > > > -- Chris Lilley @svgeesus Technical Director @ W3C W3C Strategy Team, Core Web Design W3C Architecture & Technology Team, Core Web & Media
Received on Tuesday, 17 September 2019 06:02:39 UTC