- From: david poehlman <david.poehlman@handsontechnologeyes.com>
- Date: Mon, 29 Nov 2004 09:23:08 -0500
- To: "Will Pearson" <will-pearson@tiscali.co.uk>
- Cc: "Protocolls and formats" <w3c-wai-pf@w3.org>, <wai-xtech@w3.org>
Will and all, Thanks for the explanation which fits with what I'd have expected in this situation and which, I can imagine would provide a rich environment under certain circulstances. This presupposes a number of htings however and I feel may be treading on some dangerous ground with regard to backward compatibility and current capability and learning curve that semantically rich mark up can largely avoid. I think at the least, you'd have to specify the square as either vertical or horrizontal lines so as you explore the square, it would say vertical line followed by its ifnormation such as length, position and color and thickness. then, when you come to the horrizontal line, it would be expressed as a horrizontal line in the same fashion. Your example then as I understand it would look something like: verticle Line: 10, 10 20, 10 - color: green horrizontal line: 10, 20, 20, 20 - color: green verticle line: 10, 10, 10, 20 - color: green horrizontal line: 20, 10, 20, 20 - color: green I may not be getting this exactly right, but having a verticle line at the left, a horrizontal line at the top, a vertical line at the right and a horrizontal line at the bottom seems a fitting approach although still a bit high on the perceptual curve. The other problems I see is when we add stimuli we get into the realm of loosing a lot of our audience even though the mappings are already available through the vOICe it is still quite difficult to use these relationships to augment our environment in a meaningfull way and we also leave out those who require a tactile approach. What lisa and others are proposing in a rich semantic approach can accomplish much of the same and meet the requirements of those who need a tactile approach and also at least to some degree maintain backward compatibility. Johnnie Apple Seed ----- Original Message ----- From: "Will Pearson" <will-pearson@tiscali.co.uk> To: "david poehlman" <david.poehlman@handsontechnologeyes.com> Cc: "Protocolls and formats" <w3c-wai-pf@w3.org>; <wai-xtech@w3.org> Sent: Monday, November 29, 2004 5:46 AM Subject: Re: Keyboard Navigation For Document Exploration In SVG 1.2 Hi Dave; For a green square you could have something like: Line: 10, 10 20, 10 - color: green line: 10, 20, 20, 20 - color: green line: 10, 10, 10, 20 - color: green line: 20, 10, 20, 20 - color: green Admittedly, it's a rather large set of attributes to process in order to work out it's a green square. You would have to use something like the V Buffer to display them all, as according to George Miller's 1956 theory on short term memory, we can only remember between five and nine chunks of information in our short term memory. So, whilst it's accessible, as people can determine it's a gree square, it's not very usable, requiring an increased cognitive workload to determine the spatial relationships between the lines in order to determine the shape as being a square. However, if we look beyond speech as an output modality, it becomes a lot easier. As you're probably aware from my ASVS project, and to some extent, from the work of Evreinov and Meijer, you can display shapes using sound pixels. The basic concept is that you replace visual pixels of light with auditory pixels of sound. This just changes the communications channel used to convey the information, but will still allow the same perceptual techniques, such as the Gestalt laws of perception, to be applied to the auditory rendering as would be applied to the visual. So, you could determine that something was a line by having pixels grouped together with the same horizontal alignment for vertical lines, and the same vertical alignment for horizontal lines. Then by shothe lines in parallel, it becomes a lot easier and quicker to examine the spatial relationships between the lines and determine it's a square. Most attributes, such as font size, bold, italic, etc. are just differences in spatial relationship, and having this parallelism makes for easier determination of spatial relationships. As for color, well we usually have a hearing range from 20Hz to 20KHz. We're capable of detecting changes in tonal frequency at around the 10Hz to 15Hz mark, and so that would give us around 1300 to 2000 different states that could be signified through changes in frequency. Build in mechanisms for zooming to overcome the differences in auditory definition compared to visual definition, and something to simulate saccade movements, and you've got an auditory equivalent to visual output, well, what you actually have is the current thinking on my ASVS project *smile*, but it looks to work in theory *gsmile*. So, I think that if we look beyond speech, having the user extract the semantic meaning becomes a lot more usable. I noticed from Al's draft agenda for this week's PF, that tactile graphics are on there. Maybe this agenda item could be rescoped to include sonic graphics, although being output it's probably more in the domain of ua. Will ----- Original Message ----- From: "david poehlman" <david.poehlman@handsontechnologeyes.com> To: "Will Pearson" <will-pearson@tiscali.co.uk> Cc: "Protocolls and formats" <w3c-wai-pf@w3.org> Sent: Sunday, November 28, 2004 4:53 PM Subject: Re: Keyboard Navigation For Document Exploration In SVG 1.2 > Will, For most people, the leap is too hard to make. Can you send us an > example of what we'd have to extract meaning out of in text form? The > entire discussion to this point follows: > > Johnnie Apple Seed >
Received on Monday, 29 November 2004 14:23:42 UTC