Unpacking binary data from MQTT in Javascript

While doing trawl of Stackoverflow for questions I might be able to help out with I came across this interesting looking question:

Receive binary with paho mqttws31.js

The question was how to unpack binary MQTT payloads into double precision floating point numbers in javascript when using the Paho MQTT over WebSockets client.

Normally I would just send floating point numbers as strings and parse them on the receiving end, but sending them as raw binary means much smaller messages, so I thought I’d see if I could help to find a solution.

A little bit of Googling turned up this link to the Javascript typed arrays which looked like it probably be in the right direction. At that point I got called away to look at something else so I stuck a quick answer in with a link and the following code snippet.

function onMessageArrived(message) {
  var payload = message.payloadByte()
  var doubleView = new Float64Array(payload);
  var number = doubleView[0];

Towards the end of the day I managed to have a look back and there was a comment from the original poster saying that the sample didn’t work. At that point I decided to write a simple little testcase.

First up quick little Java app to generate the messages.

import java.nio.ByteBuffer;
import org.eclipse.paho.client.mqttv3.MqttClient;
import org.eclipse.paho.client.mqttv3.MqttException;
import org.eclipse.paho.client.mqttv3.MqttMessage;

public class MessageSource {

  public static void main(String[] args) {
    try {
      MqttClient client = new MqttClient("tcp://localhost:1883", "doubleSource");

      MqttMessage message = new MqttMessage();
      ByteBuffer buffer = ByteBuffer.allocate(8);
      System.err.println(buffer.position() + "/" + buffer.limit());
      client.publish("doubles", message);
      try {
      } catch (InterruptedException e) {
        // TODO Auto-generated catch block
    } catch (MqttException e) {
      // TODO Auto-generated catch block

It turns out that using typed arrays is a little more complicated and requires a bit of work to populate the data structures properly. First you need to create an ArrayBuffer of the right size, then wrap it in a Uint8Array in order to populate it, before changing to the Float64Array. After a little bit of playing around I got to this:

function onMessageArrived(message) {
  var payload = message.payloadBytes
  var length = payload.length;
  var buffer = new ArrayBuffer(length);
  uint = new Uint8Array(buffer);
  for (var i=0; i<length; i++) {
	  uint[i] = payload[i];
  var doubleView = new Float64Array(uint.buffer);
  var number = doubleView[0];

But this was returning 3.207375630676366e-192 instead of Pi. A little more head scratching and the idea of checking the byte order kicked in:

function onMessageArrived(message) {
  var payload = message.payloadBytes
  var length = payload.length;
  var buffer = new ArrayBuffer(length);
  uint = new Uint8Array(buffer);
  for (var i=0; i<length; i++) {
	  uint[(length-1)-i] = payload[i];
  var doubleView = new Float64Array(uint.buffer);
  var number = doubleView[0];

This now gave an answer of 3.141592653589793 which looked a lot better. I still think there may be a cleaner way to do with using a DataView object, but that’s enough for a Friday night.


Got up this morning having slept on it and came up with this:

function onMessageArrived(message) {
  var payload = message.payloadBytes
  var length = payload.length;
  var buffer = new ArrayBuffer(length);
  uint = new Uint8Array(buffer);
  for (var i=0; i<length; i++) {
	  uint[i] = payload[i];
  var dataView = new DataView(uint.buffer);
  for (var i=0; i<length/8; i++) {
      console.log(dataView.getFloat64((i*8), false));

This better fits the original question in that it will decode an arbitrary length array of doubles and since we know that Java is big endian, we can set the little endian flag to false to get the right conversion without having to re-order the array as we copy it into the buffer (which I’m pretty sure wouldn’t have worked for more than one value).

Thinking Digital 2014

This week I went up to Newcastle for Thinking Digital.

It was the seventh Thinking Digital, but my first.

I’d seen a bunch of references to it being the UK’s answer to TED, the tickets aren’t cheap, videos from previous years look slick and professional, it’s held in The Sage which is a hugely impressive venue, they manage to get a great line-up of speakers, and the logistics in the run-up to the event were more organised than any event I’ve been to before.

So… I was expecting a cool and geeky, if faceless, serious, formal, and intimidating event.

I’d read it completely wrong. It’s absolutely a professionally run event. And there was no shortage of cool geekiness. But, more than that, the organizer, Herb Kim, has created a real sense of community in it. There’s a feeling of almost familial warmth amongst attendees who come year after year after year.

And they do it without being too cliquey. Everyone I spoke to was very friendly and welcoming, which made the few days a lot easier for an introvert like me. A few days being surrounded by and trying to talk to and socialise with several hundred smart brilliant people is the kind of thing I normally find hugely draining and more than a little daunting. But the crowd at TDC make it easier than most.

They value their time there, too. More than one person told me they’d paid for their own ticket and expenses to attend. I’m used to corporate-run conferences where everyone is paid for by their employer, or barcamps where people moan about being asked for a five pound deposit, so this surprised me.

The talks made for a fascinating and thought-provoking couple of days. I can’t do them justice here (when videos of the talks are available I’ll embed/link them here instead) but I want to give an idea of what the programme was like.

Jeni TennisonOpen Data Institute
Talked about the potential impact of open data on society, giving examples of how open data could be used to inform and widen access to debate.

Maik MaurerSpritz
Demonstrated their speed-reading technology – streaming one word at a time in a fixed place, for fast reading on mobile and wearable devices.

Gerard GrechTech City
Talked about the role of Tech City as a feedback loop between Government and the tech community.

Meri WilliamsChromeRose
Talked about the lessons that people managers could learn from artificial intelligence in how to inspire, motivate, and enable geeks to achieve great things.

Aral Balkanindie Phone
Gave an impassioned and stirring talk entitled “Free is a Lie” about the conflict between advertising-led business models, and user’s privacy and other interests.

David Griffithsfoam
Talked about using his background in the video game industry to combine crowd-sourcing and gaming to perform impressive citizen science projects.

Chi OnwurahMP for Newcastle Central
Talked about the parallels between technology and politics as driving forces for change, and the aims of the current Digital Government Review.

Mariana MazzucatoUniversity of Sussex
Argued that the image of the private sector as entrepreneurial and public sector as meddling and restrictive is an unhelpful myth and made the case for a bolder, entrepreneurial state.

Erin McKeanWordnik
Talked about the limitations of search as a model for accessing data and the need for discovery engines to find what you don’t know you want.

Blaise Aguera y ArcasGoogle
Described the history of machine intelligence and his predictions about what the future of machine intelligence might look like.

Carl LedbetterMicrosoft
Outlined the history and evolution of digital entertainment, and described the process that went into the design of the XBox One.

Jennifer GardyBC Centre for Disease Control
Described our progress in increasing our understanding of the human genome, and where it’s complexity lies.

Peter Gregson – Cellist
Gave a representation of the genome work that Jennifer had described. Instead of a data visualisation, it was a sonification. Using a cello.

Sean CarassoFalling Whistles
Told an inspiring story of how he came to learn about the terrible things happening in Congo, and how he went about trying to bring peace.

Conrad BodmanThe Barbican
Argued for recognition of the impact of digital tech on the arts, and described his projects to exhibit and showcase video games, animation, and digital effects.

Mark DearnleyHMRC
Described the challenges and need for technology in what HMRC do, and their digital ambition for the future.

Xavier De KestellerFoster + Partners
Talked about an amazing project to build a base on the moon, using autonomous robots with 3D printing heads to print a building out of moon dust.

Susan MulcahyImperial College London
Gave an energetic performance to describe the role of the red blood cell, and the science behind understanding brain injury.

Carlos UlloaHelloEnjoy
Showed what was possible using WebGL, bringing native 3D gaming to the browser without the need for plugins.

Jonathan O’HalloranQuantuMD
Described his work to create a mobile genetic-testing device, and the potential that real-time epidemiology from a mobile device could bring.

Blaise Aguera y ArcasGoogle
Talked about changes needed in society when more jobs are replaced by technology, and his observations about changes in gender dynamics.

Steve MouldBBC
Gave an entertaining talk about how he discovered, and tried to understand the science behind, the bead chain fountain.

Tom ScottUs Vs Th3m
Ended the conference with a fantastic performance showing what the impact of technology might be like in 2030.

Dale LaneIBM
And I did a Watson talk. I really didn’t want it to seem like a sales pitch, so I tried to put it in a bigger context of being a step forwards in changing how we use computers. I talked about why I work on Watson, what motivates and inspires me about it, and why I think what we’re doing is difficult but hopefully valuable. And I walked through a short demo to explain the value I see in where we are even now. Annoying technical issues (Keynote + clicker + multiple screens = fail) aside, it went okay. It was a lot to try and fit into 20 minutes, so I talked fast. :-)


It was a fantastic event, and one I’d wholeheartedly recommend.

If you can get to a future Thinking Digital, you absolutely should.

It’s one of the most thought-provoking and interesting couple of days I’ve had in a long time.


Full-diclosure: As a speaker, I didn’t have to pay for a ticket to attend this event. My travel and accommodation costs were paid for by IBM.

W4A : Accessibility of the web

This is the last of four posts sharing some of the things I saw while at the International World Wide Web Conference for w4a.

Several presentations looked at how accessible the web is.

Web Accessibility Snapshot

In 2006, an audit was performed by Nomensa for the United Nations. They reviewed 100 popular websites for conformance to accessibility guidelines.

The results weren’t positive: 97% of sites didn’t meet WCAG level 1.

Obviously, conformance to guidelines doesn’t mean a site is accessible, but it’s an important factor. It’s not sufficient, but it is required. Conformance to guidelines can’t prove that a website is accessible, however there are some guidelines that we can be certain would break accessibility if not followed. So they are at least a useful starting point.

However, 2006 is a long time ago now, and the Internet has changed a lot since. One project, from colleagues of mine at IBM, is creating a more up to date picture of the state of the web. They analysed a thousand of the most popular websites (according to Alexa) as well as a random sampling of a thousand other sites.

(Interestingly, they found no statistically significant difference between conformance in the most popular websites and the randomly selected ones).

Their intention is to perform this regularly, creating a Web Accessibility Snapshot, with regular updates on the status of accessibility of the web. It looks like it could become a valuable source of information.

Assessing accessibility

There was a lot of discussion about how to assess accessibility.

One paper argued there is an over-reliance on automated tools and a lack of awareness of the negative effects of this. They demonstrated a manual review of websites, comparing results with output from six popular tools. Their results showed how few accessibility problems automated tools discover.

Accurately assessing a website against accessibility guidelines doesn’t necessarily mean that you can prove a site is accessible or easy to use.

Some research presented suggests guidelines only cover a little over half of problems encountered by users. Usability studies suggest some websites that don’t meet guidelines may be easier to use than websites that do, as users may have effective coping strategies for (technically) non-compliant sites. This suggests we need a better way of assessing accessibility.

A better approach might be to observe users interact with a website and assess based on their experiences. One tool presented, WebTactics, showed an automated approach to assessing accessibility by observing a user and identifying behaviours they employ.

Another paper detailed how to add accessibility monitoring to a live website by adding additional JavaScript that captures and evaluates mouse clicks and button presses client-side before submitting them to a server for processing. Instead of requiring the user to perform predefined, and perhaps artificial, tasks, they hope to be able to discover tasks implicitly – that common tasks will emerge from the low-level actions that they collect.

Accessibility training

Given that most websites have some sort of accessibility problems, there was some talk about how this could be improved.

One project presented showed training that has been developed to raise awareness of how people with disabilities access the web, and the implications of the accessibility guidelines. It’s a practical course including hands-on assignments, and looks like it could be the sort of thing that could help web developers make a real difference.

Social Accessibility

Another project is using crowd-sourcing to improve web sites that already exist. Social Accessibility, another IBM project, enables volunteers to make web pages more accessible to the visually impaired.

It provides a mechanism for accessibility problems to be gathered directly from visually impaired users. Volunteers are then notified, and can respond using a tool that allows them to externally modify web pages to make them more accessible. It lets them publish metadata associated with the original web page. This can be applied to the web page for all visually impaired users who visit it in future using this tool, so that many users can benefit from the improvement.


Finally, a project called cloud4all is developing a roaming profile that stores your preferences in a way that multiple services can access. The focus is on accessibility – a user can store their accessibility needs in one place, and then interfaces can use this to adapt for them.

Dyslexia at W4A

This is the third of four posts sharing some of the things I saw while at the International World Wide Web Conference for w4a.

There were a few sessions presenting work done to improve understanding of how to better support people with dyslexia.

One interesting study investigated the effect of font size and line spacing on the readibility of wikipedia articles.

This was assessed in a variety of ways, some of which were based on the reader’s opinions, while others were based on measurements made of the reader during reading and of their understanding of the content after. The underlying question (can we make Wikipedia easier to read for dyslexics?) was compelling. It was also interesting to see this performed not on abstract passages of text, but in the context of using an actual website.

Accessibility isn’t just about the presentation but also the content itself. Another study looked at strategies for simplifying text that could make web pages more readable for dyslexic readers.

It compared the effectiveness of two strategies: firstly, providing synonyms on demand – giving a reader a way to be able to request an alternative for any word. The second was providing synonyms automatically – with complex words automatically substituted for simpler equivalents. Again, this was assessed in several ways, such as the speed of reading, the reader’s comprehension, on the reader’s opinion of easiness, on the effort it took (e.g. interpreting facial expression, etc.), on fixation duration measured using eye tracking, and so on.

On a more practical note, there were also tools presented that are being created to help support people with dyslexia.

Firefixia is a Firefox toolbar extension being created by colleagues of mine in IBM. It provides options for users to customise the web page they are looking at, offering modifications that have been demonstrated to make it easier for dyslexic users.

Dyseggxia is an impressive looking iPad game that aims to support children with dyslexia through fun word games.

W4A : Future of screen readers

This is the second of four posts sharing some of the things I saw while at the International World Wide Web Conference for w4a.

Several of the projects that I saw showed glimpses of a possible future for screen readers.

I’ve written about screen readers before, and some of the challenges with using them.

Interactive SIGHT

One project interpreted pictures of charts or graphs and created a textual summary of the information shown in them.

I’m still amazed at this. It takes a picture of a graph, not the original raw data, and generates sensible summaries of what it shows.

For example, given this image:

It can generate:

This graphic is about United States. The graphic shows that United States at 35 thousand dollars is the third highest with respect to the dollar value of gross domestic product per capita 2001 among the countries listed. Luxembourg at 44.2 thousand dollars is the highest


The dollar value of gross domestic product per capita 2001 is 25 thousand dollars for Britain, which has the lowest dollar value of product per capita 2001. United States has 1.4 times more product per capita 2001 than Britain. The difference between the dollar value of gross domestic product per capita 2001 for United States and that for Britain is 10 thousand dollars.

The original version was able to process bar graphs, and was presented to W4A in 2010. What I saw was an extension that added support for line graphs.

Their focus is on the sort of graphics found in newspapers and magazines – informational, rather than scientific graphs. They want to be able to generate a high level summary, rather than a list of plot points that require the user to build a mental model in order to interpret.

For example:

The image shows a line graph. The line graph presents the number of Walmmart’s sales of leather jackets. The line graph shows a trend that changes. The changing trend consists of a rising trend from 1997 to 1999 followed by a falling trend through 2006. The first segment is the rising trend. The rising trend is steep. The rising trend has a starting value of 1890. The rising trend has an ending value of 36840. The second segment is the falling trend. The falling trend has a starting value of 36840. The falling trend has an ending value of 12606.

The image shows a line graph. The line graph presents the number of people who started smoking under the age of 18 in the US. The line graph shows a trend that changes. The changing trend consists of a rising trend from 1962 to 1966 followed by a falling trend through 1980. The first segment is the rising trend. The rising trend is steep. The second segment is the falling trend.

It’s able to interpret an image and recognise trends, recognise how noisy or smooth it is, recognise if the trend changes, and more. Impressive.

Interpreting data in tables

Another project demonstrated restructuring data tables in web pages to make them easier to explore with a screenreader.

They have an interesting approach of analysing an HTML table and reorganising it to make it more accessible, abstracting out complex sections into a series of menus.

For example, given a table such as this:

it can produce navigable menus such as this:

Even quite complex tables, with row and column spans, which would otherwise be quite difficult to interpret if read row-by-row by a screenreader, is made much more accessible.

Capti web player

Another technology I saw demonstrated was the Capti web player.

Tools such as instapaper and read it later have showed that we can take most web pages and extract the body text for the article on the page.

This capability should be ideal for visually impaired users, but the tools themselves are still quite difficult to use and integrate poorly with assistive technologies. Someone described them as obviously “designed by sighted people for sighted people”.

Capti combines this capability with an accessible media player making it easy to navigate through an article, move through a list of articles, and so on. To a sighted user like me, it looked like they’ve mashed together instapaper with an audiobook-type media player. I often listen to podcasts while I go running, and am a heavy user of pocket and Safari’s reading list. So this looks ideal for me.

Multiple simultaneous audio streams

Finally, one fascinating project looked at how to make it quicker to scan large amounts of content with a screenreader to find a specific piece of information. I’ve written before that relying on a screenreader (which creates a sequential audio representation of the information on the page, starting at the beginning and going through the contents) can be tremendously time-consuming, and that it results in visually impaired users taking considerably more time to find information on the web.

This project investigated whether this could be improved by using multiple simultaneous sound sources.

It sounds mad, but they’re starting from observations such as the cocktail party effect – that in a noisy room with several conversations going on, we’re able to pick out a specific conversation that we want to listen for. Or that a student not paying attention in a lecture will hear if a lecturer says something like “this will be on the exam”.

They’re looking at a variety of approaches, such as separating the channels directionally, so one audio stream will sound like it’s coming from the left, while another is in front. Or having different voices, such as different genders, for the different streams. It’s an intriguing idea, and I’d love to see if it could be useful.

Web technologies I saw at W4A


Last month I went to the International World Wide Web Conference for w4a. I saw a lot of cool web technologies and accessibility projects while I was there, so thought I would share links to some of the more interesting bits.

There are too many to put in a single post, so I’ll write a few posts to cover them all.


Subtitles and transcripts came up a few times. One study presented looked at online video, comparing single-line subtitle captions overlaid on the video with multi-line off-screen transcripts adjacent to it.

It examined which is more effective from a variety of perspectives, including readability, reader enjoyment, the effect on understanding and so on. In summary, it found that overlaid captions are generally better, although transcripts are better for content which is more technical.

Real-time transcription from a stenographer at W4A

We had subtitles for all the talks and presentations. Impressively, a separate screen projected a live transcription of the speaker. For deaf attendees, it allowed them to follow what the speaker was saying. For talks given in Portuguese, the English subtitles allowed non-Portuguese speakers like me to understand.

They did this by having live stenographers listening to an audio feed from the talks. This is apparently expensive as stenography is a skilled expertise, and it needs to be scheduled in advance. It’s perhaps only practical for larger conferences.

Legion Scribe

This was the motivation for one of the more impressive projects that I saw presented : Legion Scribe, which crowd-sourced real-time captioning so that you wouldn’t need an expert stenographer.

Instead, a real-time audio stream is chopped up into short bits, and divided amongst a number of people using Mechanical Turk. Each worker has to type the short phrase fragment they are given. The fragments overlap, so captions that each worker types can be stitched back together to form captions for the whole original audio stream.

All of this is done quickly enough to make the captions appear more or less in real-time.

Seriously impressive.

And they’re getting reasonable levels of coverage and accuracy. The system has been designed so that workers don’t need to be experts in the domain that they’re transcribing, as they’re only asked to type in a few words at a time not whole passages. With enough people, it works. If they have at least seven workers, it’s approaching the coverage you can get with a professional stenographer.

Assuming that Mechanical Turk can provide a plentiful supply of workers, then this would not only be cheaper than a stenographer, but also let you start captioning at a moments notice, rather than needing to arrange for a stenographer in advance.

Map Reduce in the browser

Speaking of crowd-sourcing, the idea of splitting up a large computing task between a large number of volunteer computers isn’t new. SETI@home is perhaps the best known, while World Community Grid is a recent example from IBM.

But these need users to install custom client software to receive the task, perform it and submit the results.

One project showed how this could be done in web browsers. A large computing task is divided up into map reduce jobs, which are made available through a website. Each web browser that visits the website becomes a map reduce worker, running their task in the background using web workers. As long as the user remains on the site, their browser can continue to contribute to the overall task in the background, without the user having had to install custom client software.

It’s an elegant idea. Not all sites would be well suited to it, but there are plenty of web sites that I keep open all day (e.g. GMail, Remember The Milk, Google Calendar, etc.) so I think the idea has potential.

Migrating browser sessions

An interesting project I saw showed how the state of a browser app could be migrated from one browser to another, potentially a different browser running on a different machine even a different platform.

This is more than just the client-server session, which you could migrate by transferring cookies. They’re transferring the entire state of dynamic AJAX-y pages: what bits are open, enabled, and so on, for any arbitrary web app.

Essentially, they started by wanting to be able to serialize the contents of window, so that it could transferred to another browser where it could be used to restore from.

That wouldn’t be enough. window doesn’t have access to local variables in functions, it wouldn’t have access to most event listeners such as those added with addEventListener, it wouldn’t have access to the contents of some HTML5 tags like canvas, it wouldn’t have access to events scheduled with setTimeout or setInterval, and so on.

Serializing window gets you the current state of the DOM which is a good start, but not sufficient to transfer the state for most web apps.

A prototype system called Imagen shows how this could be done. Looking at how they’ve implemented it, they’ve had to resort to using a proxy server which intercepts JavaScript going to the browser and instruments it with enough additional calls to let them access all of the stuff that wouldn’t normally be in scope. This is enough for them to be able to serialize the entire state of the page.

I can see a lot of uses for this, such as in testing, debugging or service scenarios, as well as just the convenience of being able to resume work in progress as you move between devices.

Inferring constraints on REST API query parameters

Many web services include constraints and dependencies for the query parameters. For example: “this option is always required”, “that parameter is optional”, or “you have to specify at least one of this or that”. For example, the twitter API docs explain how you have to specify a user_id or screen_name when requesting a user timeline.

One project I saw was an attempt to automatically infer these rules and dependencies through a combination of natural language processing to recognise them in API documentation, and automated source code analysis of sample code provided for web services. It combines these into an estimated model of the constraints in the REST APIs, which are then verified by submitting requests to the API.

They demonstrated it on APIs like twitter, flickr, last.fm, and amazon, and it was surprisingly effective.


Finally, there was a keynote talk on Wednesday by the founder of duolingo.

Captcha is particularly interesting because it uses a task that people need to do anyway (verify that they’re human) to crowd-source the completion of a task that needs to be done (digitise the text of old books that cannot be read by automated OCR).

Duolingo is similar. It takes a task that people need to do, which is to learn a new language, and uses that effort to translate texts into different languages.

It’s better explained by their demo video.

It’s been around for a little while, but I’d not come across it before. Since getting back from www, I’ve been trying it out. Even Grace has been using it to improve her French and seems to be getting on really well with it.

What else?

There were a lot of other cool projects and technologies that I saw, so I’ll follow this up with another post or two to share some more links.

Everybody Technology

This afternoon I went to Everybody Technology, an event to discuss the need for technology to be inclusive and made in a way that is “so smart, so simple and so powerful it works for everybody”.

A highlight of the afternoon was Stephen Hawking – perhaps one of the best examples of the power of technology to enable someone to reach their potential. He also supported the event by lending his voice to a promotional video which explains the idea better than I can.

“Who is Technology Made For?” (YouTube)

There were several speakers. I won’t do them justice, but I did jot a few notes…

Panel discussion with Rupert Goodwins (ZDNet UK) & Damon Rose (BBC)

They talked of the stigma of using “special” equipment created especially for the blind. There were examples where even when technology or tools exist that can help, people don’t always want to use them. Maybe because they feel embarrassed, or they don’t want to be different, or even that they’re struggling with feeling forced to join a group of people they don’t feel a part of.

They discussed how it was more acceptable to use technologies when they are “standard” and how some felt more comfortable using technology that doesn’t single them out as being different.

Someone noted how people can be embarrassed wearing a hearing aid to help them hear, whilst few people would be embarrassed to wear glasses to help them see. Why are some assistive technologies more culturally acceptable than others?

There was a lot of mention of iDevices and appreciation of assistive technology being delivered as iPhone apps. To everyone else, it’s an iPhone and doesn’t stand out as being different. In addition, the fact that it’s mass-manufactured has meant that an expensive collection of advanced sensors and processing capability can be made affordable. An equivalent device produced purely as an assistive technology would be prohibitively expensive. The iPhone sparked a smartphone revolution that made this technology affordable in a way that it wasn’t before.

There was also discussion about how the app culture removed barriers between potential users and developers. Affordable sensors and technology made widely available, combined with a low-cost delivery mechanism for software innovations, make possible innovations in assistive technology that would have been impossible a few years ago.

Presentation on accessible architecture by Paul Kalkhoven

This looked at parallels between buildings and software. Disability became accepted as important in architecture and you can’t build a new building without considering accessibility. This isn’t yet true of technology.

He talked of the conflicting interests of design and utility. When designing a building, you want it to be unique and different. However, you want it to be obvious. If you want to find a toilet or fire exit, you want to understand the layout immediately. The same applies to technology: we want to make something new and exciting. But there is an expectation that it should be usable without a manual. It needs to be accessible.

One observation I hadn’t really recognised: transport buildings lead the way for accessible architecture, often abiding by a common, albeit unwritten, set of standards.

He challenged us to consider what technologists could learn from their experience.

Presentation on talking TVs by Mark Vasey (Panasonic)

Voice guidance is included as standard in most new Panasonic TVs, offering text-to-speech guidance for complex TV menus.

Perhaps more interesting was how they made it happen. He talked about challenges such as the cost of development, licensing and royalties for a feature they include “for free”. There were challenges in marketing to a minority, without wanting to classify it as a specialist product, and without making sighted users think that they were paying for a feature they didn’t need or want.

Similar to the discussion of the iPhone’s impact, he explained how the only way they could do this and make it affordable was to make it standard. Making a specialist TV with accessibility features for the visually impaired would not have been affordable. Spreading the cost across their entire product line is what made it possible.

“Introduction to Voice Guidance on Panasonic talking TVs” (YouTube)

Presentation on Threedom Phone – Antony Ribot (Ribot)

Antony gave a thought-provoking presentation about their project to make the world’s simplest smartphone.

The smartphone revolution has been great for many, but isn’t suitable for everyone. For some, the controls are too small, or too fiddly, or just too complicated. What if we made a smartphone that had only three buttons? Could we provide the essential functions that people need on a device with three large, easy to press, easy to understand, buttons?

He had an example with him and made a convincing case that there is a need for a device like this, in a market where devices are racing to get more complicated.

Everybody Technology : rlsb.org.uk/everybody

A year ago, I wrote about RLSB’s event which brought together a handful of representatives from tech companies, consumer-facing businesses, Universities, and charities for the blind. We talked about a vision of a Conversational Internet.

A year later, and RLSB got together a couple of hundred people to talk about projects that had happened – both by them, such as the Conversational Internet prototype that I presented, and by others such as Panasonic’s collaboration with RNIB to produce Voice Guidance.

They talked about what comes next, establishing a new group to bring together technologists and designers with people who understand disabilities, to make real their vision where everyone is taken into consideration.

If you think this is something you can help with, either as a developer, designer, or someone who understands a disability, then why not join them.

Conversational Internet


We’ve built a prototype to show how we could interact with the Internet using a command-driven approach.

  • A screen reader, but one that uses machine learning and natural language processing, in order to better understand both what the user wants to do, and what the web page says.
  • One that can offer a conversational interface instead of just reading out everything on the page.

It’s a proof-of-concept, but it’s an exciting idea with a lot of potential and we’ve got a demo that shows it in action.

The problem : screen readers today

I’ve written about this before but here is a recap.

Visually impaired people can interact with the web using screen readers. These read out every element on a page.

The user has to make a mental model of the structure of the page as it’s read out, and keep this in their head as they arrow-key around the page.

For example, on a news site’s front page, once the screen reader has read out the page, you have to remember if the story you want is the fifth or sixth story in the list so you can tab the right number of times to get to it.

Imagine an automated telephone menu:
“for blah-blah-blah, press 1, for blather-blather-blather, press 2, for something-or-other, press 3 … for something-else-vague, press 9 …”

Imagine this menu was so long it took 15 minutes or more to read.

Imagine none of the options are an exact match for what you want. But by the time you get to the end, you can’t remember whether the closest match was the third or fourth, or fiftieth option.

The vision : a Conversational Internet

Software could be smarter.

If it understood more about the web page, it could describe it at a higher, task-oriented level. It could read out the relevant bits, instead of everything.

If it understood more about what the user wants to do, the user could just say that, instead of working out the manual navigation steps themselves.

The vision is software that can interpret web pages and offer a conversational interface to web browsing.

Continue reading