Re: [EXTERNAL] Re: Canvas Floating Point Color Values Propoal

Does that discuss clipping to 0-1 range for int?

 

Lars

 

From: Chris Lilley <chris@w3.org>
Date: Friday, November 11, 2022 at 9:38 AM
To: "public-colorweb@w3.org" <public-colorweb@w3.org>
Subject: Re: [EXTERNAL] Re: Canvas Floating Point Color Values Propoal
Resent-From: <public-colorweb@w3.org>
Resent-Date: Friday, November 11, 2022 at 9:37 AM

 

EXTERNAL: Use caution when clicking on links or opening attachments.

 

Yes, it certainly makes sense to explicitly point out that CSS Color 4 defines the transfer function over the extended range for all the predefined RGB spaces.

On 2022-11-11 04:38, Christopher Cameron wrote:

Thanks -- those are covered by CSS Color Level 4's definition, which is linked in the canvas spec. But, I'll add a remark putting together that connection in the document.

 

On Thu, Nov 10, 2022 at 6:25 PM Lars Borg <borg@adobe.com> wrote:

Does that apply? Uint8 would only support the unit range.
So maybe the floats would get clipped?

Lars

-----Original Message-----
From: Reiner Fink <reinerf@microsoft.com>
Date: Thursday, November 10, 2022 at 7:16 AM
To: Christopher Cameron <ccameron@google.com>, Lars Borg <borg@adobe.com>
Cc: Ken Russell <kbr@google.com>, "public-colorweb@w3.org" <public-colorweb@w3.org>
Subject: RE: [EXTERNAL] Re: Canvas Floating Point Color Values Propoal

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You might want to mention how to resolve gamma for values >1.0 and <0.0, eg something about extending curves and reflecting gamma about y-axis.

-reiner

From: Christopher Cameron <ccameron@google.com>
Sent: Thursday, November 10, 2022 6:34 AM
To: Lars Borg <borg@adobe.com>
Cc: Ken Russell <kbr@google.com>; public-colorweb@w3.org
Subject: [EXTERNAL] Re: Canvas Floating Point Color Values Propoal

Thanks!

I've created a PR incorporating this feedback, and also fixing a couple of inconsistencies at
https://nam04.safelinks.protection.outlook.com/?url=https%3A%2F%2Fgithub.com%2Fw3c%2FColorWeb-CG%2Fpull%2F85&amp;data=05%7C01%7Cborg%40adobe.com%7Ce4f7137b602d447f8fa308dac33f4a5a%7Cfa7b1b5a7b34438794aed2c178decee1%7C0%7C0%7C638036973867549789%7CUnknown%7CTWFpbGZsb3d8eyJWIjoiMC4wLjAwMDAiLCJQIjoiV2luMzIiLCJBTiI6Ik1haWwiLCJXVCI6Mn0%3D%7C3000%7C%7C%7C&amp;sdata=yoD92G0l59OcIJWW0nd0fN7NsdTPod70KyuzpIOc8Zs%3D&amp;reserved=0

In particular, I was inconsistent about using "unorm8" versus "uint8Clamped" for ImageData. I also changed ImageDataSettings to use "dataType" instead of "colorType", since we are specifying the type for ImageData's data member (BTW, would it better to use the full names of the type "Uint8ClampedArray" and "Float32Array", rather than the abbreviated "uint8Clamped" and "float32").

Let me know of any further feedback here or on the PR.


On Wed, Nov 9, 2022 at 2:54 AM Lars Borg <mailto:borg@adobe.com> wrote:
Needs statements about conversion between unorm8 and float16 representations.
I assume such conversions will be needed.

Also, spell out that the float16 encoding is as per IEEE?

Lars

From: Ken Russell <mailto:kbr@google.com>
Date: Tuesday, November 8, 2022 at 2:57 PM
To: Christopher Cameron <mailto:ccameron@google.com>
Cc: "mailto:public-colorweb@w3.org" <mailto:public-colorweb@w3.org>
Subject: Re: Canvas Floating Point Color Values Propoal
Resent-From: <mailto:public-colorweb@w3.org>
Resent-Date: Tuesday, November 8, 2022 at 2:57 PM

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Looks great to me!


On Tue, Nov 8, 2022 at 5:47 AM Christopher Cameron <mailto:ccameron@google.com> wrote:
As discussed in the previous call, I've separated floating point pixel values from HDR canvas capabilities.

The following document is that proposal.
https://nam04.safelinks.protection.outlook.com/?url=https%3A%2F%2Fgithub.com%2Fw3c%2FColorWeb-CG%2Fblob%2Fmaster%2Fcanvas_float.md&amp;data=05%7C01%7Cborg%40adobe.com%7Ce4f7137b602d447f8fa308dac33f4a5a%7Cfa7b1b5a7b34438794aed2c178decee1%7C0%7C0%7C638036973867549789%7CUnknown%7CTWFpbGZsb3d8eyJWIjoiMC4wLjAwMDAiLCJQIjoiV2luMzIiLCJBTiI6Ik1haWwiLCJXVCI6Mn0%3D%7C3000%7C%7C%7C&amp;sdata=Aekkng0xasOSgAC%2FO%2F8rbIfxO7HlzTOqXCU8UOcLXeU%3D&amp;reserved=0

Please provide any feedback you have on the proposal. I will be trying to get this landed in the HTML spec first, and then introduce the HDR canvas proposal separately.




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Chris Lilley
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W3C Strategy Team, Core Web Design
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