Really appreciate this link. I used a LG C2 as my monitor and I've been having trouble with HDR content in W11/Chrome for years. I always end up using Edge or otherwise for Youtube HDR, and this helped me debug.

Doesn’t work on iPhones — the most common high quality HDR display people I know are likely to use.

I can’t use this technique to publish my photos to them.

I can use an Apple format to send HDR images to my friends and relatives with Apple devices.

I can use some other Adobe or Google formats to send pictures to my friends with Android (=Google) phones.

Etc…

We don’t have any new widely adopted open standards any more in today’s FAANG era of mutually antagonistic fiefdoms.

At best one of them muscles out the competing formats and that becomes a defacto standard.

For everything else we’re stuck with pre-FAANG standards established at a time when companies were smaller, didn’t “own” the whole stack top to bottom, and were forced to cooperate.

Google owns that hardware (Pixel), OS (Android), browser (Chrome), protocol (HTTP3, Brotli), codec (VP9, WEBM), and television itself (YouTube).

There’s an identical stack for Apple.

Why do you imagine it’ll ever be possible for Google user to send a full fidelity photo to an Apple user?

They live on opposite sides of a new iron curtain.

They’re not even permitted to text each other properly!

> Why do you imagine it’ll ever be possible for Google user to send a full fidelity photo to an Apple user?

It's possible today. Apple may just not give you the ability to actually view the image though.

Touché.

They also prevent others from giving you that ability (at least as far as content on the web goes).

Ask your beloved Apple, they are the ones who love their walled gardens.

I think Facebook, Apple and everybody else in VR agrees on GLTF as a model interchange format.

> I can use an Apple format to send HDR images to my friends and relatives with Apple devices.

Switch your iPhone to use "high compatibility" or something like that and it'll spit out jpegs with hdr gainmaps that chrome and Android understand as well now. It's not the Adobe spec, but given Apple is now publicly talking about gainmaps ( https://developer.apple.com/documentation/appkit/images_and_... ) and the Adobe spec is a superset of capabilities with a patent-free license and an ISO draft proposal it doesn't seem unimaginable that Apple will move it.

But if Apple won't ever support it, that doesn't mean iPhones can't view it. You already can today with the latest version of Lightroom. And of course Chrome on MacOS already lets you view them. Apple's iOS browser monopoly is hurting you here, but that's very obviously an exclusively Apple created problem

Something is utterly busted about the spec and the patent system. Look at the Swift code for decoding the headroom! It stinks — maybe Apple tried a few different transfer functions or for size and didn’t bother to mark which version was in use? And now Apple is kindly offering to license the patent if this goes into an ISO standard?

I’m sorry, but a system to decide old nonsensical formats should not require a license.

Also… the gain map is subsampled 1:2. Surely this will cause annoying artifacts at sharp edges where one side is much brighter.

> And now Apple is kindly offering to license the patent if this goes into an ISO standard?

The one that's likely to go to an ISO standard is the Adobe spec here: https://helpx.adobe.com/camera-raw/using/gain-map.html (which is the same as Google's "UltraHDR")

And that has a blanket public grant for usage.

> Also… the gain map is subsampled 1:2.

Subsampling is optional, you can do 1:1 if you want.

From https://gregbenzphotography.com/hdr/#tests:

“Note for Safari / iPhone users: The top image on this page (the building with the before/after slider) uses a workaround which shows an HDR video as if it were a photo. This will let you get a sense of the HDR benefit, but you will fail the tests below as Safari / WebKit (which means all iPhone/iPad browsers) only supports HDR video and not HDR photos at this time.” :-(