Re: Agenda, TPAC 2019 ColorWeb CG Meeting.

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.

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

Received on Monday, 16 September 2019 09:37:07 UTC