MessageHi Jamal, I agree, but would stress that visual effects do contribute to the semantic content of an interface, and therefore contribute to a user's understanding of the purpose of that interface component and how they are required to interact with it to perform their intended activity. The thing we need to establish, is whether we can create a system that can extract this semantic content on behalf of the user, which I'm sure we can do at least for some scenarios, or whether the fallback position of presenting the encoded information to the user and allowing the to extract the semantic content has to be taken. Will ----- Original Message ----- From: Jamal Mazrui To: ossrp-control@xxxxxxxxxxxxx Sent: Tuesday, May 31, 2005 9:17 PM Subject: [ossrp-control] Re: What Is A Screen Reader? Hi Will, I agree that a screen reader will often have to guess probabalistically, rather than be able to know determinatively, all the semantic meaning intended by visual aspects of layout, including spacing, fon choices, etc. My hope though is that we develop the huristic analysis capability as much as possible, separating what is functionally significant from visually decorative or at least redundant. What is the purpose of the dialog? What task does it enable the user to accomplish? These are more importantquestions, in my opinion, than what are all the visual effects presented to a sighted user? Jamal ----Original Message----- From: ossrp-control-bounce@xxxxxxxxxxxxx [mailto:ossrp-control-bounce@xxxxxxxxxxxxx] On Behalf Of Will Pearson Sent: Sunday, May 29, 2005 2:39 PM To: ossrp-control@xxxxxxxxxxxxx Subject: [ossrp-control] Re: What Is A Screen Reader? Hi Jamal, It's difficult to quantify the semantics conveyed by a particular physical encoding scheme in a general sort of way. There's multiple characteristics of space, namely position, proximity and size. These can convey semantics, or they may not, in one scenario, size may be used to convey relative importance, whilst in another scenario it may be used to differentiate between two or more groups of items by having the items in each group a different size compared to those in another group. This is also true for other mechanisms by which semantics can be encoded visually, such as color, font, and font attributes such as bold, italic, etc. So, it's very difficult to determine what semantics, if any, are encoded using a particular technique in a scenario devoid of context. There's a couple of ways that this can be presented to a user. Firstly, you can have some form of intelligent system that will extract the semantics from the visual presentation and convey the semantics to the user, either in raw form using additional spoken words, or by altering the attributes of the spoken text associated with the item for which the semantics are being conveyed. The major drawback to this is that it's very hard to create the intelligence to do this in an autonomous manner, and so the system would have to be taught the relationships between encoding techniques and the semantics they convey in the various different contexts. The second method of conveying the content is to take the encoded semantics, e.g. spatil position, color, etc. and convey this to the user but altering it's physical presentation. So, instead of conveying spatial relationships through parallel presentation of different elements, you could convey the spatial positioning of each element, and thus the rrelationship, through a series of spoken co-ordinates, which would still leave space as the encoding technique for conveying semantics, but would modify the physical representation of that encoding to speech. A similar thing could be done for color, where instead of altering te wavelength of the displayed element, you could just use speech to say the color of the item, which would still leave color conveying the semantics. Alternatively, you could have parallel auditory displays that use different frequencies/wavelengths to present the information. That's just some of the ways in which it could be done, and they're by no means designs. One point that I think needs to be born in mind when thinking about this sort of thing is the limitations of speech. Firstly it's serial in nature, and so the more you produce in terms of speech the more time it takes someone to receive that semantic content, and secondly, people have a short term memory limit of between five and nine chunks of information, at least according to George Miller's 'Magical number seven, plus or minus two' theory. Speech being serial in nature doesn't allow a user to very easily quickly jump back to a position to review the content at that position, so people tend to have to remember the content as they go, and this is stored in their limited short term memory. I think it's something that needs some careful consideration to come up with the optimal design. Will ----- Original Message ----- From: Jamal Mazrui To: ossrp-control@xxxxxxxxxxxxx Sent: Thursday, May 05, 2005 9:22 PM Subject: [ossrp-control] Re: What Is A Screen Reader? Good point. That is a different, more complex example, but certainly such scenarios are also common. I think the scenario that I described often occurs with order forms on the web, typically asking for contact and credit card information in a familiar pattern. In evaluating this issue, at least two questions seem relevant: (1) what does spatial information convey about the function of the dialog? and (2) to the extent that functional rather than asthetic information is being conveyed, what is the best way to achieve an equivalent result nonvisually? If there are optional subgroups of fields, then tabbing through all of them is, indeed, inefficient. To achieve productive data entry, let us separate function from presentation. The blind person probably does not need to know, for example, how many pixels separate controls in order to judge which ones are part of the same subgroup and which are part of another. The fact that the border of group boxes uses a 3D rather than simple style is inconsequential. The objective is to enable the blind person to identify and navigate to the different subgroups. For the screen reader user, a multi-page tab dialog might be the most efficient solution rather than a single page dialog where subgroups are indicated by spatial proximity. Jamal -----Original Message----- From: ossrp-control-bounce@xxxxxxxxxxxxx [mailto:ossrp-control-bounce@xxxxxxxxxxxxx] On Behalf Of David Lant Sent: Thursday, May 05, 2005 3:46 PM To: ossrp-control@xxxxxxxxxxxxx Subject: [ossrp-control] Re: What Is A Screen Reader? Hi Jamal, Broadly I understand your point. However, there are situations where simply going sequentially through the items in a dialog is not the process required for daily use of a facility. If, for example, your job is processing pay claims, and allocating charge codes to the relevant portions of hourly rates, overtime rates, expenses and so on, it would, and does, become extremely tedious having to tab through all the fields that may have to be displayed to inform you what needs to be done. It may be much quicker, if the pieces of information are all grouped in one control group, and the fields you need to fill in are in an adjacent one. There may very likely be other data on the screen at the same time, which don't relate directly to the job in hand. Sighted people visually skip over that stuff, such as the box at the top giving the identification summary of the person and their pay reference etc. They see that the boxes they need to work with are all in two rectangles on the right of the screen, one above the other, and so visually concentrate on those. They will glance through the information in the first box, to identify the hours being claimed, and will then click in the second box to place an insertion pointer so they can type in the relevant charge codes. For a blind person to do this, they would need to have a quick way to rapidly get to the information in the upper right box, and read it. Then, to equally rapidly, move to the lower right box, in order to start filling in the information. It is true that the fact that these boxes are on the right of the screen may be of no significance whatsoever as far as both the blind and sighted person are concerned. But the significance is that they separate out the information that has to be dealt with, so that the details on the left of the screen can be largely ignored unless something special turns up. This, I think, is the kind of scenario that Will is talking about. Not just the fact that address fields are grouped together, but that you may need to perform specific, and isolated tasks on that group, separate from the rest of the data on the screen. All the best, David -----Original Message----- From: ossrp-control-bounce@xxxxxxxxxxxxx [mailto:ossrp-control-bounce@xxxxxxxxxxxxx] On Behalf Of Jamal Mazrui Sent: 05 May 2005 08:21 To: ossrp-control@xxxxxxxxxxxxx Subject: [ossrp-control] Re: What Is A Screen Reader? Hi Will, I agree that spatial relationships can and do convey a lot of information to sighted users. I was not arguing that visual placement is generally irrelevant, but maintain that it can be so for blind users where it does not affect the interface we experience and the functionality of the task at hand. For example, if the purpose of a dialog is to retrieve typical contact information (name, address, phone, etc.) through a well-understood set of fields, then it may be irrelevant to the blind user where the controls are placed, as long as they speak properly. The layout of the dialog is not an end in itself, but a means to an end, that of gathering the data for a contact record. The database does not care, and does not track, where the controls were placed in the input dialog that gathered the data for the record that was saved. To elaborate, I might press tab successively hearing fields like "First name", "last name," etc., filling each one in, including reviewing the data in each edit box. If the tab order is logical and the field name and current value speak as expected, than it does not matter to me how the fields are aligned, what fonts are used for field names, what point size the entered characters are, etc. Sighted users, on the other hand, are affected by such characteristics. Even if the tab order is the same, logical sequence, they will be confused if the "City" field is placed above the "First Name" field. If a few fields are cramped together in one corner of the dialog in an unpleasing manner aesthetically, their productivity will be reduced because of the disorientation they experience, etc. Jamal -----Original Message----- From: ossrp-control-bounce@xxxxxxxxxxxxx [mailto:ossrp-control-bounce@xxxxxxxxxxxxx] On Behalf Of Will Pearson Sent: Wednesday, May 04, 2005 4:25 PM To: ossrp-control@xxxxxxxxxxxxx Subject: [ossrp-control] Re: What Is A Screen Reader? Hi Jamal, "As a blind user, placement can actually be irrelevant, having no effect on functionality." Based on psychology, semiotics and communications theory, I would have to disagree with that statement. A control's relationship to other controls and it's absolute positioning can be sources of semantic information about that control's functionality. For example. buttons grouped together may have similar functionality, buttons placed next to a list box may perform an action on that list box or it's selected index. On the web, a row of links placed in vertical alignment at the top of a page are often used as a quick navigational group of links. So. spatial relationships and absolute positioning can add a lot of meaning regarding functionality beyond that conveyed by a simple text label. Users can, and often do, work out the full semantic nature of a control, but this is often through trying out the control and seeing what it does, which is inefficient at best, and possibly disasterous at worst, imagine deleting something that you didn't actually mean to delete. Will ----- Original Message ----- From: Jamal Mazrui To: ossrp-control@xxxxxxxxxxxxx Sent: Monday, May 02, 2005 2:41 PM Subject: [ossrp-control] Re: What Is A Screen Reader? Just an observation to share. In trying to program dialog boxes under Windows, I have experienced the situation where something I developed worked well with a screen reader, yet I subsequently discovered that it was almost unusable for a sighted person. A screen reader can tab from one control to another, and as long as each control is properly labeled and otherwise voicing as one would expect at the time it has focus, then the controls in the dialog serve their purpose. It may be the case, however, that the controls are placed in visually peculiar, unbalanced, or overlapping places on the screen, thus making the dialog difficult for a sighted user. As a blind developer, I need to know the location of controls so that I can meet the needs of both sighted and blind users. As a blind user, placement can actually be irrelevant, having no effect on functionality. Regards, Jamal -----Original Message----- From: ossrp-control-bounce@xxxxxxxxxxxxx [mailto:ossrp-control-bounce@xxxxxxxxxxxxx] On Behalf Of Lyn Eagers Sent: Saturday, April 30, 2005 11:19 PM To: ossrp-control@xxxxxxxxxxxxx Subject: [ossrp-control] Re: What Is A Screen Reader? Hi Will and Others, Will, I found your description of what a screen reader is quite interesting. I train people to use screen readers and, from my experience, some blind folk are interested in where things are on the screen (spacial perception) and others are not. In particular, those who have had sight and were extremely visual people find it important to know where things are. Some, and I say some, so therefore not all, long term blind people don't seem to be interested in the spacial factor. I am a long term blind person and have always tried to grasp a mental picture of what is on the screen and where - probably because I teach both kinds of blind people and sometimes assist sighted folk. Anyhow, I thought I'd share my experiences with you. Cheers, Lyn ----- Original Message ----- From: Will Pearson To: ossrp-control@xxxxxxxxxxxxx ; uvip@xxxxxxxxxxxxxxx Sent: Sunday, May 01, 2005 11:58 AM Subject: [ossrp-control] What Is A Screen Reader? Hi, I thought I'd share my, rather academic, view of what a screen reader is. It offers a little glimmer into what screen readers could potentially do, and some of the pitfalls that the current crop of screen readers have fallen into. All this is from the viewpoint of human computer interaction, psychology and communications theory. OK. So, what is a screen reader? Well, it's actually a lot more than people often assume it is. It's not just something that grabs the text from the screen and reads it to you, well, at least it shouldn't be, it is in fact the interface by which user and machine communicate semantic meaning, relating to thoughts, concepts, actions and states. So, how did I arrive at this view? As some of you may know, I've been researching into semantics and their role in software interfaces for a while now. During this time, it's become apparent that software interfaces are just intended to communicate semantic meaning, but as we're not capable of extr sensory perception and telepathy with the computer, we need some way to indicate our thoughts, concepts, actions, etc. to the computer, and vice versa. The way this is visually done is by placing elements on the screen, such as icons, buttons, etc. and having their shape, colour, position on screen and relationships to one another act as encoding channels by which the semantic meaning is conveyed. Users then just point to an object, conveying the semantics of which element they would like to interact with, and either click it or select an action to perform on it from a menu. All this is just a form of physical encoding of the semantic meaning between user and machine and vice versa. So, as a screen reader is a replacement for the visual interface, it's role is simply to act as an interface between user and machine and convey the semantic meaning generated by the machine. However, there's a nasty twist, and that is that a screen reader has to get the semantic meaning that it is to communicate to the user from somewhere. As the screen reader has no access to the internals of the machine, it's only available source of semantics that the machine wishes to convey is the visual interface, which uses encoding techniques such as colour, shape, position and spatial relationship to convey it's semantics. So, a screen reader should really be about extracting the semantics from the visual display and encoding them in a non-visual form suitable for a blind user, and this is where current screen readers fall down. To maintain accurate and efficient communication with the user, all the semantics that are conveyed visually need to be conveyed to the user. This includes things like spatial positioning and spatial relationships between interface elements, things that are currently lost to the user when they are using one of the current screen readers. If this were to happen, then the number of errors, and according back-tracks and reissuing of commands that go along with errors, would decrease, and screen reader users would be more efficient beasts. I haven't gone into design specifics, as they're for another day, and these can dramatically affect efficiency as well, but that's my thoughts of what a screen reader should be doing. In focusing on the semantics, then it's likely that through the use of semantic translation access to all those difficult accessibility problems could be increased. Will