Jacob Rus wrote: "Tom Lianza's statement is, as Jan-Peter says, incorrect. Both the CSS and SVG specifications address this question." Jacob obviously did not read the entire thread. My comment was directed at general color management, not the specification of a color space. I ABSOLUTELY pointed out that the specification referenced sRGB as the standard color space and all colors had to be rendered to that space. All colors were therefore assumed to be in that space. The Web was always defined as "output referred" and the connection between display and web was fixed and defined. Based upon that specification, the display had to be adjusted to the sRGB specification and no further colormanagment should be required. The fact that both sRGB and REC 709 share the exact same colorimetric primaries and very similar transfer functions, implies that if you generate the content properly, motion and still images should appear as produced on a properly adjusted display. In the last ICC steering committee meeting, I requested that we put together a program aimed at getting proper color management into the web browser. We are targeting this conference for November 2011 in San Jose. We are trying to get the proper folks from the various committees together in a room to put together a plan moving forward. Within the ICC, we will put together a "best current practice" document to specify a recommended practice and workflow for current web applications. At the same time, we are coordinating the development of an X-rite approved electronic version of the color checker that is rendered properly for various lighting conditions. This target will be used for testing photographer's workflows to ensure that they are numerically "correct". It's not clear, at the moment, what "correct" actually means, but once we have tested the workflows, we will document them numerically. I want to emphasize that ICC is trying to be responsive in these areas, but we are not the regulating authority on these issues. It will also require some consumer demand, which to date has been very small. If you combine that with the billions of legacy images rendered to sRGB and REC 709, there is a huge legacy inertia that needs to be properly addressed. This will not be an easy task at any level. Regards, Tom Lianza -----Original Message----- From: Jacob Rus [mailto:jacobolus.ml@gmail.com] Sent: Wednesday, June 01, 2011 12:36 AM To: homann@colormanagement.de Cc: colorsync-users@lists.apple.com; Thomas Lianza Subject: Re: / Re: Color management in web browsers Tom Lianza:
Mark, that is not the reason the problem is not addressed. It was NEVER part of the Web specification, that is the reason it is not addressed. My own feeling is that color management "on the web" will not be handled by a browser, but by a web application. There are solutions to this, but they won't be free.
Jan-Peter Homann:
So far as I know, several W3C specifications reference, that untagged data (images and graphic content) should be handled as sRGB in the document to monitor chain. [...]
In think, it is the most important task of the ICC today to develop recommendations how the different levels of colormanagement should interact: - application level - OS level - device level
I will start also a task about this, at the internal ICC Graphic Arts Special interest Group and give some feedback to the Colorsync Mailinglist if something relevant happens there...
Tom Lianza's statement is, as Jan-Peter says, incorrect. Both the CSS and SVG specifications address this question. In the "color" section of SVG, http://www.w3.org/TR/SVG/color.html
All SVG colors are specified in the sRGB color space [SRGB]. At a minimum, SVG user agents shall conform to the color behavior requirements specified in the color units section and the minimal gamma correction rules defined in the CSS2 specification.
In CSS, http://www.w3.org/TR/2008/REC-CSS2-20080411/syndata.html#color-units
All RGB colors are specified in the sRGB color space (see [SRGB]). User agents may vary in the fidelity with which they represent these colors, but using sRGB provides an unambiguous and objectively measurable definition of what the color should be, which can be related to international standards (see [COLORIMETRY]).
Unfortunately, the HTML 5 canvas specification does not include any * * * I and others have been pressuring browser vendors to do proper color management of CSS colors for years now, without tremendous progress. Some useful links include: http://regex.info/blog/photo-tech/color-spaces-page3 http://www.webkit.org/blog/73/color-spaces/ https://bugzilla.mozilla.org/show_bug.cgi?id=16769 https://bugs.webkit.org/show_bug.cgi?id=9567 http://code.google.com/p/chromium/issues/detail?id=2602 My (possibly incorrect) recollection of the current state of browsers is: * Firefox has color management for CSS colors and untagged images (i.e. can assume they are sRGB), but it is turned off by default, leaving colors in the display's color space. I don't know whether images tagged with a color profile are treated properly when that setting is off. They might be. * Safari has color management for images with embedded profiles, but not for untagged images or CSS/SVG/etc. colors. The excuse given in 2006 (!) was that because Adobe Flash colors were not color managed, other colors could not be either without causing a mismatch which would break the color coordination of web pages. * Chrome (inexcusably; one of the dozens of deal-breaker compatibility problems with that browser) does not support any kind of color management. * Opera also (and also inexcusably) does no color management. I don't know what the story is for Internet Explorer, for Adobe Flash, or for mobile devices like Android phones or iPads, but I wouldn't have high expectations for any of them. Essentially every browser currently violates the W3C specifications w/r/t color management, which is extremely frustrating for anyone who cares about both color and the web. Cheers, Jacob Rus The information contained in this e-mail and any accompanying attachments may contain information that is privileged, confidential or otherwise protected from disclosure. If you are not the intended recipient of this message, or if this message has been addressed to you in error, please immediately alert the sender by reply e-mail and then delete this message and any attachments. Any dissemination, distribution or other use of the contents of this message by anyone other than the intended recipient is strictly prohibited. The company accepts no liability for any damage caused by any virus transmitted by this email or any attachments.