- From: Loretta Guarino Reid <lorettaguarino@google.com>
- Date: Tue, 11 Dec 2007 15:49:02 -0800
- To: S.Vassallo@e-bility.com
- Cc: public-comments-wcag20@w3.org
Thank you We have added the rationale to the Understanding document. "The working group feels that 200% is a reasonable accommodation that can support a wide range of designs and layouts, and complements older screen magnifiers that provide a minimum magnification of 200% and that the majority of images of text used on the web these day can be zoomed up to 200% without pixelation being a significant barrier." NOTE: Based on comments from Japan, we have removed the requirement that text be sizable down to 50% because shrinking Japanese characters by half causes legibility problems. It is recommended however. Regards, Loretta Guarino Reid, WCAG WG Co-Chair Gregg Vanderheiden, WCAG WG Co-Chair Michael Cooper, WCAG WG Staff Contact On behalf of the WCAG Working Group > > ---------------------------------------------------------- > > Comment 6: Text resizing - What Level > > Source: http://lists.w3.org/Archives/Public/public-comments-wcag20/2007Jun/0281.html > > (Issue ID: 2111) > > ---------------------------- > > Original Comment: > > ---------------------------- > > > > The ability to resize text can be critical to accessibility for people > > with print disabilities such as degenerative eye sight and > > reading/learning difficulty but this does not seem to be adequately > > covered in the Guidelines. > > > > 1. SC 1.4.4 Resize Text is a Level AA requirement (rather than Level A) > > > > 2. Text as an image appears to be acceptable, yet images are not > > resizable by many browsers and where image "zoom" is a feature of > > the browser this can create other accessibility problems such as > > broken page formats, horizontal scroll bars and pixelation of the > > text/image. Turning images off to view the alt text is not a practical > > solution, since many people do not know how to do this and once set > > this preference applies to all images not just text images. It becomes > > increasingly difficult when text based images are used for navigation > > elements, such as an image map. > > > > 3. Resizing of text based form content and form controls also does not > > seem to be mentioned and textual content in non-text based form > > controls also needs to be resizable by the user. For example: using > > the browser resizing options in forms is problematic when the text > > resizes but not the radio button. > > > > Proposed Change: > > 1. Move SC 1.4.4 to Level A > > > > 2. Text as an image should not be acceptable unless Success Criterion > > are applied that would address the needs of people with print > > disability > > > > 3. Include Success Criterion for resizing of text based and non-text > > based form controls > > > > --------------------------------------------- > > Response from Working Group: > > --------------------------------------------- > > > > RE # 1. Move SC 1.4.4 to Level A > > > > This provision may not be implementable with some technologies > > directly but the same effect could be achieved with assistive > > technologies. Because of these factors the Working Group feels that > > his provision is better put at Level AA. The working group examined > > the issue of images of text carefully and felt that they should be > > allowed,. > > > > The group feels that the majority of images of text used on the web > > these day can be zoomed up to 200% and down to 50% without pixelation > > being a significant barrier. For zooming above that AT have smoothing > > algorithms. The group also feels that there are sufficient resources > > in the operating system and with external AT devices that contrast > > issues can be handled at level AA. However, we have made a note in the > > understanding document describing some of the problems with images of > > text such as contrast and pixelation, and we encourage text. And we > > have added a note to 1.4.3. > > > > For 1.4.3: Note: Images of text do not scale as well as text because > > they tend to pixelate. It is also harder to change foreground and > > background contrast and color combinations for images of text, which > > is necessary for some users. Therefore, we suggest using text wherever > > possible, and when not, consider supplying an image of higher > > resolution. > > > > For 1.4.4: Note: Images of text do not scale as well as text because > > they tend to pixelate, and therefore we suggest using text wherever > > possible. It is also harder to change foreground and background > > contrast and color combinations for images of text, which are > > necessary for some users. > > > > RE #3 Include Success Criterion for resizing of text based and > > non-text based form controls > > > > We think this should be a User Agent guideline, and just an > > advisory/repair technique in WCAG. If text is big enough to be > > useful, it will be so big that designers won't want to use it. If some > > elements scale and others don't, the layout is likely to get messed > > up. Whether that's a barrier or not depends on whether content or > > functionality is lost, but it's much eaiser to get this right when > > everything scales such as a user agent zoom, commercial AT, or > > operating system magnification. However we have added a sufficient > > technique for 1.4.4: "Specifying the size of objects in terms of the > > font size" > > > > By the time WCAG reaches recommendation, we expect Zoom features in > > browsers will become more and more used among people who need moderate > > amounts of zoom. We realize that this is not perfect, but we think it > > is the best compromise given the alternatives. > > > > > -------------------------------- > Response to response > -------------------------------- > > Thanks for the time the WG put into reviewing this. I still feel that > this should be a Level A requirement, not least because of the aging > population. However, if it is to remain at Level AA then it would be > helpful to include the WG rational above as part of the requirement for > accessibility, since this provides a measurable benchmark for legibility > of images used ie that they can be zoomed up to 200% and down to 50% > without pixelation affecting readability.
Received on Tuesday, 11 December 2007 23:49:13 UTC