Re: Conversions for HDR Canvas Specification

On 2021-06-16 11:53, Simon Thompson - NM wrote:
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> Hi all,
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> I’ve added a list of suggested colour forward and reverse transforms 
> between extended-sRGB, extended-linear-sRGB and bt2100-hlg and a 
> suggested simple tone-mapping for displaying bt2100-hlg on an sRGB 
> display to issue #50 - https://github.com/w3c/ColorWeb-CG/issues/50.  
> I’ve tried to follow the style of the example in TTMLv2 provided by 
> Pierre.
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> I can recalculate the matrices to a different number of significant 
> figures if necessary – is there a consensus on accuracy levels for 
> web operations?
>
In general, since "space of the printed publication"is no longer a 
concern, I prefer to list to full precision.

I have seen several problems arising from round-off errors and 
round-tripping, so there is no good reason to round off.

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> Would Dolby colleagues be able to add the bt2100-pq versions to the 
> list?  There is a PQ example in Pierre’s TTMLv2 link.
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> Best Regards
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> Simon
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> *_                                          
> _*
> *Simon Thompson*
> Senior R&D Engineer**
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-- 
Chris Lilley
@svgeesus
Technical Director @ W3C
W3C Strategy Team, Core Web Design
W3C Architecture & Technology Team, Core Web & Media