Thread Subject: Re: FW: Revised proposal for Sec.4.AdditionalProvisions for Audio-Visual Players or Displays
Note
This archival content is maintained by WebAIM and NCDAE on behalf of TEITAC and the U.S. Access Board . Additional details on the updates to section 508 and section 255 can be found at the Access Board web site.
From: Gregg Vanderheiden
Date: Wed, Aug 29 2007 12:50 PM
- Return to this mailing list's archives
- View all messages in this thread
- Next message in thread: None
- Previous message in thread: Gregg Vanderheiden: "Re: FW: Revised proposal for Sec. 4.AdditionalProvisions for Audio-Visual Players or Displays"
- Messages sorted by: Author | Thread | Date
Comments in GV:
Gregg
-- ------------------------------
Gregg C Vanderheiden Ph.D.
_____
From: = EMAIL ADDRESS REMOVED =
[mailto: = EMAIL ADDRESS REMOVED = ] On Behalf Of Andrew
Kirkpatrick
Sent: Wednesday, August 29, 2007 11:18 AM
To: TEITAC Audio/Video Subcommittee
Subject: Re: [teitac-video] FW: Revised proposal for
Sec.4.AdditionalProvisions for Audio-Visual Players or Displays
Gregg,
- all platforms (flash, avi, mov etc) have a standard way of providing
captions
You don't mean "platforms" here, right? :)
GV: not software platforms no. bad choice of words.
That may be true for Video in Flash (FLV) and mov, but not for AVI.
GV: the suggestion was that all NEEDED to have a STANDARD form or else
players have to support ALL forms.
Also, it is worth noting that there is not _a_ standard way to provide
captions, there are multiple standard ways in some cases (e.g. embedded
caption data in a MOV or externally referenced QTtext caption data - this is
similar in FLV also)
GV: Right - but if one is not labeled as STANDARD or REQUIRED then
players must support them ALL since authors may use any of the many - and
captions need to be viewable.
- For content - Captions must be provided in that format
Since there are multiple ways to deliver the caption data, which way are you
suggesting?
- For players that play that format - they must display captions AND
either have an easy way to turn them on (even if embedded in content) or
play them OPEN (always on).
this partsounds fine, but I agree with Sean's "easy" comment.
AWK
Gregg
-- ------------------------------
Gregg C Vanderheiden Ph.D.
_____
From: = EMAIL ADDRESS REMOVED =
[mailto: = EMAIL ADDRESS REMOVED = ] On Behalf Of Schomburg, Paul
Sent: Wednesday, August 29, 2007 9:34 AM
To: TEITAC Audio/Video Subcommittee
Subject: Re: [teitac-video] FW: Revised proposal for Sec.
4.AdditionalProvisions for Audio-Visual Players or Displays
Greg: These are good questions; unfortunately I'm not aware of a closed
caption standard that could be applied today to all personal video products.
I don't know any other way to handle this except on an agency-by-agency
basis.
Without a unified standard, interoperability would be handled by content
authoring tools that would support conversion among different timed text
metadata. Thus a broadcast video content encoded with 708 could be
re-encoded with a different time text standard when being deployed for
mobile devices. That's why we added: "Support interoperability and
conversion between other common caption formats such as CEA 608, CEA 708, or
Timed Text (e.g. DFXP)."
Thanks, Paul
_____
From: = EMAIL ADDRESS REMOVED =
[mailto: = EMAIL ADDRESS REMOVED = ] On Behalf Of Gregg
Vanderheiden
Sent: Tuesday, August 28, 2007 11:19 PM
To: 'TEITAC Audio/Video Subcommittee'
Subject: Re: [teitac-video] FW: Revised proposal for Sec. 4.
AdditionalProvisions for Audio-Visual Players or Displays
Thanks
Couple questions about the part where you changed it to
"Uses this standard.
Captions or timed text (as defined by procuring agency) or display open
caption video"
- How would you get interoperability if each agency picks its own standards?
- Will purchasing agents have any idea what to specify?
- And how would a mfgr know how to design products if they don't know what
standard will apply until the get the P.O.?
Maybe I'm missing something
Thanks
Gregg
-- ------------------------------
Gregg C Vanderheiden Ph.D.
_____
From: = EMAIL ADDRESS REMOVED =
[mailto: = EMAIL ADDRESS REMOVED = ] On Behalf Of Schomburg, Paul
Sent: Tuesday, August 28, 2007 4:49 PM
To: TEITAC Audio/Video Subcommittee
Subject: [teitac-video] FW: Revised proposal for Sec. 4.
AdditionalProvisions for Audio-Visual Players or Displays
Folks: I am forwarding this without the attachments in order to allow
timely review. The attachments may come through later after the TEITAC AV
email list moderator approves my post, which apparently exceeded the maximum
size limit due to the attachments.
Best regards, Paul
_____
From: Schomburg, Paul
Sent: Tuesday, August 28, 2007 5:26 PM
To: TEITAC Audio/Video Subcommittee
Cc: Schomburg, Paul
Subject: Revised proposal for Sec. 4. Additional Provisions for Audio-Visual
Players or Displays
Folks: In response to comments on today's call we are providing a revised
draft for tomorrow's discussion (see below proposed text). To help
everyone's understanding I have attached in MS-Word clean and redlined
versions of the proposal. The redline shows differences from the EWG draft
at:
http://teitac.org/wiki/EWG:Draft_Aug_17#4._Additional_Provisions_for_Audio-V
isual_Players_or_Displays
Since the feedback we received today indicated that a "readily achievable"
clause could not be used I have changed the section for personal video
devices to leave the selection of closed caption or time text standard up to
the procuring agency or to allow use of open captions. I have also removed
references to screen sizes.
Best regards, Paul
-------------
4. Additional Provisions for Audio-Visual Players or Displays
4-A - Caption Playback
Analog television, digital television and tuners, computer equipment, and
other equipment must provide closed and open captions:
1. Equipment of this type:
* Analog television displays that measure 13 inches or more diagonally
* Computer equipment that includes analog television receiver or
display circuitry
Uses this standard:
* CEA 608
To provide these functions:
* Receive, decode and display signals from
* broadcast
* cable
* satellite
* Optical disc, videotape, and other recorded media
* other recorded media
2. Equipment of this type:
* Wide-screen (16:9) digital television (DTV) displays measuring at
least 7.8 inches vertically
* DTV sets with conventional (4:3) displays measuring at least 13
inches diagonally
* Stand-alone DTV tuners, whether or not they are marketed with
display screens
* Computer equipment that includes DTV receiver or display circuitry
Uses this standard:
* CEA 708
To provide these functions:
* Receive, decode and display signals from:
* broadcast
* cable
* satellite
* Optical disc, videotape, and other recorded media
* IPTV
OR
* Decode data, when available, and pass a decoded ("open-captioned")
video signal to the DTV display or monitor
3. Equipment of this type:
* Other digital video source products without broadcast reception
capability, such as video playback products for removable media (e.g.
optical disc, tape, flash memory, etc.), IP-enabled video playback products
for downloaded or streaming video content, and media player software, that
is procured for the purpose of displaying video on a DTV display or monitor
Uses this standard:
* CEA 708 or timed text with functionality equivalent [or comparable]
to CEA-708 (see end-note for definition of functional equivalent)
To provide these functions:
* Pass CEA-708 caption data, when available, to the caption decoding
circuitry of DTV displays
OR
* Decode caption data, when available, and pass a decoded
("open-captioned") video signal to the DTV display or monitor.
4. Equipment of this type...
Personal video display products with an integrated display and without
broadcast reception capability.
Uses this standard.
Captions or timed text (as defined by procuring agency) or display open
caption video
To provide these functions.
- Decode caption data or timed text, when available, for viewing on
the integrated display
Material for inclusion in the additional notes document:
TEITAC definition of "Functional Equivalent" to CEA 708
Equivalent text display functionalities must:
* Support caption placement control by caption authors for any
position within the TV safe area.
* Support standard, large, and small caption sizes and must allow the
caption author to choose a size and allow the viewer to choose an
alternative size.
* Support eight font variations. Caption authors may specify one of
these eight font styles to be used to write caption text. Equivalents must
include the ability for users to choose among the eight fonts. The
equivalent must display the font chosen by the caption author unless the
user chooses a different font.
* Support the eight font styles defined as follows: default
(undefined), monospaced with serifs (similar to Courier), proportionally
spaced with serifs (similar to Times New Roman), monospaced without serifs
(similar to Helvetica Monospaced), proportionally spaced without serifs
(similar to Arial and Swiss), casual font type (similar to Dom and Impress),
cursive font type (similar to Coronet and Marigold), and small capitals
(similar to Engravers Gothic).
* Support author and user choice of eight character foreground and
eight character background colors: white, black, red, green, blue, yellow,
magenta and cyan).
* Support author and user selection of character and background
opacity options: SOLID, TRANSLUCENT, TRANSPARENT [FLASH option deleted]
* Support options for altering the appearance of caption character
edges.
* Support the authoring and selection of the six caption services, but
information from only one service need be displayed at a given time.
* Include an option that permits a user to choose a setting that will
display captions as intended by the caption provider (a default).
Equivalents must also include an option that allows a viewer's chosen
settings to remain until the viewer chooses to alter these settings,
including during periods when the video source device is powered off.
Multimedia content creation products and/or software must:
* Support the creation of equivalent text display functionalities as
listed above
* Support interoperability and conversion between other common caption
formats such as CEA 608, CEA 708, or Timed Text (e.g. DFXP).
- Next message in Thread: None
- Previous message in Thread: Gregg Vanderheiden: "Re: FW: Revised proposal for Sec. 4.AdditionalProvisions for Audio-Visual Players or Displays"