Re: Color Management in HTML5?

On Mar 5, 2010, at 8:42 AM, Frank Olivier wrote:

> From my interpretation of the canvas spec: canvas is always in  
> device color space. A canvas.DrawImage(tagged image) call should  
> convert colors into the device color space.

That is certainly what our implementation does currently. In general,  
though, I think canvas colors should be treated the same as CSS  
colors. Developers may want to match colors in their canvas with a  
solid background or static images for example.

Regards,
Maciej

>
> From: public-html-request@w3.org [mailto:public-html-request@w3.org]  
> On Behalf Of Maciej Stachowiak
> Sent: Friday, March 05, 2010 12:09 AM
> To: Leonard Rosenthol
> Cc: public-html@w3.org
> Subject: Re: Color Management in HTML5?
>
>
> On Mar 4, 2010, at 10:24 PM, Leonard Rosenthol wrote:
>
>
> I am sitting in a meeting of the ICC (International Colour  
> Consortium) and the question about whether (or how) HTML5 address  
> colour management issues came up. So I did a quick search of the  
> current draft of the document and the ONLY reference I could find  
> was that color specifications are in sRGB.  No mention about  
> profiles in images, etc.
>
> Is this indeed the case?  Has any consideration been given to richer  
> color management of data (esp. images) present in HTML5 documents?
>
> If not, is there any reason that the ICC could not present a Change  
> Proposal to introduce requirements for UAs in this manner?
>
> Most color management issues on the Web are not in the domain of  
> HTML5. Color management of CSS colors (e.g. colors use for text,  
> background colors, border colors, etc) is an issue for CSS. I  
> believe there is a proposal to allow CSS colors from an arbitrary  
> colorspace to be used. Nominally, CSS colors are in the sRGB  
> colorspace by default.
>
> Color management of images is an issue for the image format specs  
> and/or a quality-of-implementation issue.
>
> Color management of video is up to the video format specs and/or a  
> quality-of-implementation issue.
>
>
> Just to report on what Safari does: we colormatch images that are  
> tagged with an explicit colorspace, but we treat CSS colors and  
> colors in untagged images as being in the device color space  
> (instead of treating as sRGB). This seems to give a good balance  
> between performance for the common case and color-correctness for  
> cases where precise color is desired.
>
> Regards,
> Maciej
>