Thread Subject: Re: Recommendations for 1-G text size

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From: Gregg Vanderheiden
Date: Tue, Feb 19 2008 11:05 AM


Hi Paul, All,



(also relates to Rob Nerhoods post)





1) we should add a note that says "this provision is met by content
that does not specify font size"



2) for TVs or devices that are too small - the provision would just be
'not met'. Presumably all devices of the same size would have the same
problem and not meet the guideline. Purchasers would then either purchase
larger items that could be used by people with low vision - or they would
decide that the size was an important factor and purchase things with small
print.



3) Re keyboards. The alphabet is standard but the other keys are not.
Try using your keyboard with white stickers on all the keys.



You can touch type ok but as soon as you get off of the alpha (and for some
- the alphanumeric) keys you pretty much have to look to see where they put
the keys on this keyboard.






The encourage and notify principle




The theory on this and other provisions I think was that there will always
be some products that can't meet a provision for some reason. If so then
all would fail. (If not then those that can should have advantage). In
all cases - if a product can't meet the guideline then some people with
disabilities would not be able to use the product - and purchasers should
be notified of this when purchasing





The goal is to set minimum access requirements that, if not met or
meet-able, are flagged.



Lets talk.




Gregg
-- ------------------------------
Gregg C Vanderheiden Ph.D.






_____


From: = EMAIL ADDRESS REMOVED =
[mailto: = EMAIL ADDRESS REMOVED = ] On Behalf Of Schomburg,
Paul
Sent: Tuesday, February 19, 2008 8:24 AM
To: TEITAC Committee
Cc: Schomburg, Paul
Subject: [teitac-committee] Recommendations for 1-G text size

Folks: Thanks for the Committee's indulgence to provide an additional week
to review this issue.



In general I have no objection to the proposed requirement for minimum text
sizes in most cases, but I do not believe this should apply to DTV receivers
currently under FCC rules. Caption decoders in DTV receivers render
captioning text that is sized relative to the screen size. In most cases
(and certainly for screen sizes above 13 inches) DTV products will comply
with the requirements of 1-G, but there is no technical method in CEA-708
for defining an absolute minimum text size. Further study is required to
determine if small screen mobile video products will be able to use the same
kind of windowing environment & relative text size method as defined in
CEA-708. For these reasons, I suggest adding a new note:



Note 6: This requirement does not apply to products that are governed by
U.S. Federal Communications Commission (FCC) regulations 47 CFR 15.119 as
stipulated by 4-A - Caption Processing (Consensed).



Rationale: The FCC rules and the CEA-708 standard were designed to enable
DTV receivers to display caption text in a window on the screen that is
readable but also does not obscure the video content. Caption text is
displayed in a window relative in proportion to screen size, but an absolute
text size is not defined. Current DTV receivers with 708 decoders must
support standard, small, and large caption text size and support the ability
of the viewer to choose size, but absolute text size is still relative to
the size of the display. The "windowing" environment of CEA-708 was
designed to allow caption providers to create a targeted safe area for
caption display while allowing consumers to grow or shrink captions within
that window. Even at the large caption text size, however, very small
screen sizes may not permit display of caption text in compliance with 1-G
Text Size requirements. For video programming, this requirement can best be
met by ensuring that displays located in public places or at a person's
workstation are large enough to display caption text so that it meets the
requirements of 1-G.



Here is the current recommendation for 1-G:

1-G - Text size (Recommended, No Quorum)

There must be at least one mode where all information that is required for
product use and is provided in text is readable by people with 20/20 vision
at 3.5 times their typical viewing distance. This mode must be the default
mode unless the activation method for that mode can be done at 3.5 times the
typical viewing distance or the product automatically sets itself to that
mode for users who require it. This provision does not apply to safety
labels, regulatory labels, and marks that are not required for product use.

Note 1: Providing text in an accessible file on a device meets this
requirement for information that is not location specific (e.g. labels are
location specific).

Note 2: These are minimums and it is recommended that larger fonts be used
wherever possible on any product - either by default or as an option.

Note 3: If other means of visually conveying the information in the label or
instructions exists (e.g. uniquely tactilely discernible through shape),
then the text is not "required for product use" and the text size
requirement does not apply.

Note 4: See also 3-D-User Preferences for software products that run on
operations systems that provide a function to set user preferences.

Note 5: One way this provision may be met by using type (or in pixel
dimensions converted from point size) that is:

1. For devices designed to be located in public places or for devices used
away from a person's workstation:
a) At least 12 points if text is a label and if the user can position their
face close to the label
b) At least 14 points for all other text

2. For devices designed to be located at a person's workstation:
a) At least 10 points if text is a label and if the user can position their
face close to the label
b) At least 12 points for all other text

where 1 point = 1/72.27 inches (on computer displays 1/72 inch).


Rationale(Added Feb 6)
The goal of this provision is to support people with low vision. People with
vision worse than 20/70 typically use an assistive device, so this provision
is aimed at supporting those with vision between 20/400 and 20/70.

* For people with 20/20 vision viewing text at 40 cm (15.7 inch), 8pt
type is a small but acceptable type size.
* For people with 20/70 vision, an acceptable size is approximately
28pts at 40 cm viewing distance.
* If we assume users with low vision can move in closer (half distance
- 20 cm) to view text (and that their glasses allow this), 14 pt type would
provide type that subtends the same visual angle (as 28 pt at 40 cm).

Note 5 provides type sizes that can be used to meet the requirements of this
provision. At a workstation, it is reasonable to assume that special reading
aids (such as a moderate magnifying glass) would be available even if user's
vision is in the range of 20/30 to 20/70, and fonts can therefore be
smaller. The sizes for devices designed to be used away from a person's
workstation are aimed at those with low vision but not very low vision
(beyond 20/70). This is based on an assumption that:

* People with 20/70 vision or better would not usually carry a
magnifying device with them.
* People with worse than 20/70 vision would usually carry portable
optical magnifying devices (including special glasses) with them.



Thanks, Paul


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