Adding support for High Dynamic Range (HDR) imagery to HTML Canvas: a baseline proposal

[palemieux]

The Color on the Web CG would very much appreciate your feedback on the following strawman, which motivates and proposes baseline modifications to the HTML Canvas API to enable support for High-Dynamic Range (HDR) imagery:

https://github.com/w3c/ColorWeb-CG/blob/8eac62f15e5b41940636beb031f6214b61e933af/hdr_html_canvas_element.md

The proposed modifications allow the HTML Canvas API to manipulate High Dynamic Range (HDR) images expressed using the widespread BT.2100 PQ and BT.2100 HLG color spaces, without precluding adding future HDR capabilities, such as support for additional color spaces like a linear high-dynamic range color space.

[kdashg]

It's hard to give solid feedback on this because it is pretty far into the future on our roadmap, and the technical challenges and compromises needed are non-trivial.

[palemieux]

Please find below an updated proposal for adding support for High Dynamic Range (HDR) imagery to HTML Canvas.

https://github.com/w3c/ColorWeb-CG/blob/hdr_canvas_r2/hdr_html_canvas_element.md

Selected highlights of this revision to the proposal;

• adds a linear display-referred color space (rec2100-display-linear)
• adds display color volume information to Screen interface of the CSS Object Model
• improves color space conversion examples

Feedback, issues and questions are welcome at mailto:public-colorweb@w3.org and https://github.com/w3c/ColorWeb-CG/issues.

Contacts: @palemieux and @svgeesus (Color on the Web CG co-chairs)