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A modest attempt at speech-based assistive capabilities for any web page.
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WVCAT is a modest attempt at speech-based assistive capabilities for any web page. It started as a JavaScript library that developers could integrate into their web page and with little additional coding have speech-based assistive capabilities up and running.

The flaw with WVCAT originally being a JavaScript library was that its usefulness was more towards developers than the end-users I envisioned (users with visual impairments, mobility issues, poor hand-eye coordination, or repetitive strain injuries). My thinking then was that if the library gained wide-enough adoption owing to its ease-of-setup, the benefits would trickle down. Sure, that might have been possible but it would have taken a long time.

That line of thinking then got me wondering how exactly I could make the idea immediately useful to end-users. I thought of making a speech-based shopping app, email app, and flight booking app before the idea of making a browser extension popped into my head.

Rather than wait on developers to start adopting the library and eventually have the benefits trickle down to the end-users, I can now inject it into any web page with a browser extension. Instant wide-adoption, immediate utility to end-users.

How does it work?

After WVCAT is installed into a browser, on any page a user navigates to, WVCAT queries for controllable elements using the HTML DOM API. To WVCAT, controllable elements are HTML elements that can obtain focus. These include buttons, links, radio buttons, checkboxes, file pickers, dropdowns, text inputs, and contenteditable or focusable divs and list items.

WVCAT then attempts to assign meaningful names to those controllable elements. It does this by checking for the content of the element's aria-label attribute, title attribute, name attribute or innerText. If all these sources fail to yield a name, it generates and assigns a random name to the element. WVCAT also goes on to attach a suffix to the names of element so that the language of issued speech commands will feel natural. For example, an HTML button element with its aria-label attribute set to "submit" will have WVCAT assign "submit button" to it as a name. Speech commands for that element will then be something like "Click submit button".

Below is a table containing the suffixes of the various controllable elements.

HTML Element Suffix
select dropdown
a link
button button
contenteditable div button
div tabindex button
input[submit] button
input[reset] button
input[file] file picker
input[checkbox] checkbox
input[radio] radio button
input input
textarea input

At this point, WVCAT initializes the speech recognition engine but only if your browser has full support for the speechRecognition API. Currently supported browsers are Chrome, Opera, and soon Microsoft Edge. WVCAT attaches a white "response container" to the bottom of every web page and this is where it outputs the results of your speech commands or any other signifiers. If this never shows up, your browser does not work with WVCAT.

NB: The contents of the WVCAT response container can and will be read out by any screenreader you have installed.

After initialization, WVCAT then waits for you to press the push-to-talk key which is currently the Ctrl key. Left or right both work (opt for right though). If the push-to-talk key is pressed, you should hear or see "Listening for your command...". Speak your command and WVCAT should handle the rest.

Issuing speech commands

To issue speech commands, you need to know both the available commands and also the names of the elements those commands will target.

To know the available commands, focus on any controllable element and say "Show reference". Remember to always press the push-to-talk key before issuing a speech command.

To know the names WVCAT has assigned to the controllable elements on a web page, you can navigate normally using the Tab or Shift + Tab. Each time a controllable element gains focus, WVCAT reads and displays the name it assigned to it.

Armed with that information, you can now get started with issuing speech commands. Below is an exhaustive list of the possible commands provided out-of-the-box.

Command Description
Next Moves focus to the next controllable element in a webpage. (Equivalent to pressing the Tab key)
Previous Moves focus to the previous controllable element in a webpage. (Equivalent to pressing Shift + Tab)
Select X Finds and places focus on a controllable element named X
Click X Finds and clicks on a controllable element named X
Click Clicks on an already focused on controllable element
Open Opens an already focused on controllable link
Clear Clears any text entry in an already focused on controllable input element

Custom commands

In addition to the capabilities WVCAT provides out-of-the-box, it also allows a user to issue custom speech commands. These commands are usually domain-specific and aim at making a (complex) workflow possible solely using speech.

Custom commands can contain parameters; named or splat. You can have multiple named parameters in a command but only one splat parameter.

Named parameter example: ("Search for :query dogs")
This will match speech commands like "Search for gray dogs" or "Search for big dogs".

Splat parameter example: ("Search for *query")
This will match speech commands like "Search for blue dogs on a lawn" or "Search for white shoes".

WVCAT enables custom commands via community contributed plugins you can find here. End-users are encouraged to suggest possible custom commands and the WVCAT plugin community (myself included) will implement them as and when we are able to.

Installing WVCAT

  1. Clone this project to your computer. Alternatively, download the zip file of this project to your computer. Once downloaded, unzip it to a location of your choice.
  2. Launch Google Chrome and navigate to chrome://extensions.
  3. At the top right of the page you just navigated to, find and turn on Developer mode.
  4. The option for you to load an unpacked extension should now be available to you. Click on "Load unpacked" and choose the folder where you cloned or unzipped WVCAT to.
  5. WVCAT should now be installed in your browser. Refresh any existing tabs and WVCAT should correctly initialize in the page.

NB: This browser extension will soon be uploaded to the Chrome extension store.



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