- From: eric hansen <ehansen@ets.org>
- Date: Tue, 27 Apr 1999 03:56:44 -0400 (EDT)
- To: w3c-wai-gl@w3.org
Re: PRI-8 Alternate synchronized formats for audio-visual materials This memo attempts to address AC Member concerns regarding priorities for checkpoints 1.3 and 1.4. PART A. PRIORITY OF CHECKPOINTS 1.3 AND 1.4 I think that providing prerecorded auditory descriptions (checkpoint 1.3) should be Priority 2 rather than Priority 1, based on the definitions of Priorities. Synchronization of alternative equivalents (checkpoint 1.4), should also be Priority 2, at least for movies and animations. I accept the WCAG document's definitions of "priority", which indicate that priority is determined by "impact" (that is, adverse influence on disability-group access caused by violation of a checkpoint). What is the "basic" level of accessibility for a movie? I submit that it is simply a text transcript that collates the audio track information and the video track information. Failure to provide this "text-collation" equivalent for a movie would clearly render it impossible for individuals who are both deaf-and-blind to access the content. Collating the equivalents is essential because sequence (as in reading order) is essential; othewise one could lose track of the story-line of the movie. Without this text-collation equivalent, the movie will or may be completely inaccessible, thus making it a Priority 1 item. Does this Priority 1 solution (text collation) represent a high level of accessibility? It may about as accessible as it can be for individuals who are deaf-blind and rely on braille. The text-collation solution also provides basic accessibility for individuals who are deaf or who are blind, yet there are better solutions. For example, video and a synchronized text equivalent of the audio (i.e., captions) is a much better accessibility solution for an individual who is deaf. Also, an "auditory description" of the video synchronized with the audio track is a much better accessibility solution for someone who is blind. These Priority 2 solutions are superior and beyond the "basic" level of accessibility of Priority 1 checkpoints. As stated in the description of Priority 2 checkpoints, failure to implement the checkpoint(s) means that "one or more groups [in this case, individuals who are blind or who are deaf] will find it difficult to access information in the document." As further stated in the description of Priority 2, "Satisfying this checkpoint will remove significant barriers to accessing Web documents." The definition of Priority 2 fits checkpoints 1.3 and 1.4 very well. Does failure to provide synchronization (checkpoint 1.4) and prerecorded auditory descriptions (checkpoint 1.3) make it impossible for individuals who are deaf or who are blind to access the content? No, it is not impossible, because users have the logically-ordered text collation defined at priority 1 (checkpoint 1.1). Thus, not only do checkpoints 1.3 and 1.4 fit Priority 2 very well; they also fail to fit Priority 1. Again, the text-collation equivalent provides only a "basic" level of accessibility. But that is all it purports to do at the Priority 1 level (essentially the single-A conformance level). Implementing Priority 2 and Priority 3 checkpoints makes it possible to achieve higher levels of conformance (or accessibility) (double-A and triple-A). This approach seems analogous to how priorities are assigned to checkpoints relating to tables. Basic accessibility is Priority 1 and refinements are Priority 2. Please note that this argument does not depend upon the cost of implementing the solutions. B. SUGGESTIONS In terms of finding a solution to the current situation, I suggest the following. 1. Add a note to checkpoint 1.1. (Highly recommended) Add a note in checkpoint 1.1 (and perhaps in the glossary definition of equivalent) that states that correct presentation order is an integral part of what constitutes an equivalent or text equivalent. Following is a suggestion. "Note X [for checkpoint 1.1]. A text equivalent must have a logical sequence (e.g., reading order). Ensuring logical sequence may require special attention for text equivalents that are combine two or more other text equivalents. For example, to preserve a proper presentation sequence, a text equivalent for a movie must collate segments of the text equivalent of the audio track with segments of the text equivalent for the video track." 2. Make revisions to checkpoints 1.3 and 1.4 and reduce them from Priority 1 to Priority 2 (Necessary) The specific edits are found in a separate memo (Re: PRI-4 Animation and Movies). 3. Add additional notes in the conformance section. (Optional) Additional notes could be added to highlight and compensate for the fact that there are some checkpoints whose importance and potential benefit for users with disabilities (and others) is not adequately reflected in the current (impact-based) rating scheme. As I have indicated in times past, other methods for rating the checkpoints could have been used. For example, one could have rating scheme that incorporated information such as benefit estimates or even cost-benefit estimates. However, the current impact-based scheme is probably as reasonable as other methods we could create, and it is probably simpler! So we just need to stick with it consistently. Like any practical scheme, this scheme does not capture every nuance of what we mean by "importance." Material covered in Priority 2 and 3 checkpoints (e.g., 1.3, 1.4, etc.) may show unusually high value for people with disabilities, such that, under a different rating scheme, they might rate at the Priority 1 level. Below is a suggested revision to notes in the conformance section of the document. "Note 1.{EH: Number added} Conformance levels are spelled out in text so they may be understood when rendered to speech." {EH: New} "Note 2. Web content developers are encouraged to adhere to all checkpoints, including those beyond the conformance level that they choose. For example, even if Web content developer is working to achieve the single-A conformance level (which requires adherence only the Priority 1 checkpoints), he or she should consider adhering to many of the Priority 2 and 3 checkpoints as well. While violations of these Priority 2 and 3 checkpoints do not make Web content impossible for disability groups, adhering to them can greatly improve disability access. Furthermore, adhering to many of the Priority 2 and 3 checkpoints can greatly improve usability for all users." 4. Add Notes in Individual Checkpoints (Optional) One could say something like the following: Note for checkpoint 1.3: "Auditory descriptions, ({EH: Insert brief definition of auditory descriptions]}, tremendously enhance the "movie" experience for people who are blind {EH: Perhaps add "or who are both deaf and blind" if auditory descriptions include synthesized speech renderings.}. One could also add similar notes to guideline 5 (re: natural languages) or its individual checkpoints. C. CONCLUSION I think that these suggestions address the major concerns voiced by the AC Member. I think that this issue is of such importance that it is well worth reaching consensus. I believe that following the suggestions will help maintain credibility with the users of the document and assist significantly in the document's adoption. ============================= Eric G. Hansen, Ph.D. Development Scientist Educational Testing Service ETS 12-R Rosedale Road Princeton, NJ 08541 (W) 609-734-5615 (Fax) 609-734-1090 E-mail: ehansen@ets.org
Received on Tuesday, 27 April 1999 03:59:57 UTC