CSS dynamic-range-limit

[ccameron-chromium]

こんにちは TAG-さん!

I'm requesting a TAG review of CSS dynamic-range-limit

The goal of this proposal is to provide a mechansim through which an application may limit the maximum brightness of HDR content (including images, videos, and in the future HTML canvases and CSS colors).

• Explainer¹: https://github.com/ccameron-chromium/hdr-headroom-limit/blob/main/EXPLAINER.md
• Specification: https://drafts.csswg.org/css-color-hdr/#controlling-dynamic-range
• WPT Tests: https://wpt.fyi/results/css/css-color-hdr?label=experimental&label=master&aligned
• User research:
• Security and Privacy self-review²:
• GitHub repo:
• Primary contacts:
  • @ccameron-chromium, Google, proposal author, Chromium author
  • sboukortt, Google, Chromium implementor
  • @svgeesus Editor of CSS Color HDR spec
• Organization/project driving the specification:
• Multi-stakeholder support³:
  • Chromium comments: Positive
  • Mozilla comments: CSS dynamic-range-limit property mozilla/standards-positions#979
  • WebKit comments: CSS dynamic-range-limit property WebKit/standards-positions#312
  • Adobe requested support
• Status/issue trackers for implementations⁴:
  • https://chromestatus.com/feature/5146250411769856, https://crbug.com/40277822

Further details:

• I have reviewed the TAG's Web Platform Design Principles
• Relevant time constraints or deadlines: Aiming for Chrome 133 (early January)
• The group where the work on this specification is currently being done: CSS WG
• The group where standardization of this work is intended to be done (if different from the current group):
• Major unresolved issues with or opposition to this specification:
• This work is being funded by:

[svgeesus]

• Security and Privacy self-review²:

The spec has a Privacy Considerations which has the same description as the explainer on why we do not expose numerical headroom values, just three buckets.

The Security Considerations says that no security issues have been raised and there is also an Accessibility Considerations which explains the accessibility benefit of limiting the dynamic range.

[svgeesus]

The specification is now published to /TR