+5 votes
106 views
in Web development by (160k points)
Screen readers: web accessibility for everyone

Please log in or register to answer this question.

+3 votes
by (1.1m points)

Screen Reader and Speech Synthesizer Features
Other fields of application of screen readers
The problem of Internet accessibility
The most popular screen readers
Screen reader comparison
Reading with screen readers: most common problems
NVDA: free screen reader for Windows
JAWS: free screen reader for Windows
Dolphin: paid screen reader for Windows
Narrator: Windows' internal screen reader
VoiceOver: the pre-installed screen reader for macOS and iOS
Orca: the free screen reader for Linux
ChromeVox and Chirpy: screen readers as browser extensions
TalkBack: screen reader for Android
ShinePlus as screen reader for Android

image

Screen readers: web accessibility for everyone

Operating computers is extremely difficult for people with partial or complete blindness. However, thanks to technical development in recent years, these people have also started to use the computer in their day-to-day without major problems. With screen readers, written texts are emitted in the form of artificial voice (text to speech in Spanish) or as tactile Braille lines, thus fulfilling the objective that blind people can also use the computer. Thus, this technology allows that, in addition to the PC, these people can also manage other devices, such as smartphones, through screen reader applications..

A distinction can be made between external screen reader programs and system-side applications, which differ markedly from each other in terms of quality, size and cost. Thus, there are from free applications to software whose price even reaches four figures, and is that some of these tools use computer programs whose development costs must be recovered. The quality of the voice broadcast depends on the particular language. Thus, screen readers for the blind in English generally tend to show better results than programs in Spanish, since the development of most speech synthesizers is based on the English language.

Index
  1. Screen Reader and Speech Synthesizer Features
  2. Other fields of application of screen readers
  3. The problem of Internet accessibility
    1. Reading with screen readers: most common problems
  4. The most popular screen readers
    1. NVDA: free screen reader for Windows
    2. JAWS: free screen reader for Windows
    3. Dolphin: paid screen reader for Windows
    4. Narrator: Windows' internal screen reader
    5. VoiceOver: the pre-installed screen reader for macOS and iOS
    6. Orca: the free screen reader for Linux
    7. ChromeVox and Chirpy: screen readers as browser extensions
    8. TalkBack: screen reader for Android
    9. ShinePlus as screen reader for Android
  5. Screen reader comparison

The development of the synthetic voice is one of the main tasks of computational linguistics and, although its development is progressing, the synthetic language continues to differ considerably from the human one. For this reason, until now, users of screen reader software have in many cases had to settle for an artificial voice emission reminiscent of a robot. Since not all users may be willing to work with poor voice output, the quality of the built-in screen readers and synthesizers is extremely important..

image
Blind users operate the computer using keyboard commands or voice controls and the screen reader software translates the text into the desired medium

When choosing a screen reader it is also important that it is compatible with the devices used in the workplace . If, for example, a braille display is used, it must be compatible with the screen reader, which also applies to the computer's operating system and related software. In this selection, the answers to the following questions are also relevant: does the user only need help elements to read or also to write in the workplace? What content does he work with? What is the budget to organize the place? work for the blind?

Complex and expensive software is required for some areas of application, while in other cases free tools are sufficient. This depends on the spectrum of tasks of the user, that is, does he only have to read documents or also do searches on the Internet? How do you deal with the means of help existing in your workplace? How does collaboration with companions? In any case, a thorough workplace analysis is crucial, although the functions and scope of screen readers for the blind are also significant for private users.

Before purchasing a screen reader, check for subsidies from Social Security or the state , as the number of free tools has decreased..

Screen Reader and Speech Synthesizer Features

Screen readers read the displayed textual elements and convert the data into a synthetic voice emission or send the corresponding signals for translation to a braille device, which emits the corresponding text in tactile format.

In artificial voice emission, tones are generated with the help of synthesizers, such as Elo or eSpeak . These applications use built-in dictionaries that also show the pronunciation of most words, but rarely can a natural-sounding language be created in this way. It must be taken into account that the intonation of the same word can vary depending on its meaning within a context or its syntactic position.

In this sense, problems can also arise around the intonation of questions, as the tonal rises and falls influence the interpretation. For example, is it time? or? is it time ?? They are two different sentences, whose difference in meaning in the spoken language is revealed by intonation. In order for the speech synthesizer to correctly reproduce the second phrase, it must include it at the end of a speech upload, otherwise the user will misinterpret it as a statement.

In speech synthesis the following qualitative characteristics are especially relevant:

  • Word accentuation . The synthesizer not only has to pronounce isolated words correctly, but also to adapt the stress to its position in the phrase.
  • Transition of syllables . If the synthesizer composes the language from syllables, the transitions must be designed fluently to create understandable words.
  • Intonation of the phrase . If the ups and downs in pitch are relevant to the meaning of the phrase (something that is marked by punctuation in the written language), the synthesizer should be able to reproduce it.
  • Speech speed . The synthesizer should try to mimic the natural rhythm of the tongue so that the user gets a natural auditory impression.
  • Reading speed . Reading speed is also important to the user. At best, he sets it up himself.
  • Pauses . Formatting elements such as paragraphs and line breaks should be marked as conversation breaks to make it easy to record the beginning and end of each fragment.

Research in computational linguistics has made many advances in recent years. Google's Tacotron 2 system offers results very close to the quality of human speech. The latest developments have been made possible by the autonomous learning capabilities of modern synthesizers. Generally speaking, the program learns human language like a young child and? Composes? the language from linguistic documents. It is especially striking that Tacotron 2 is relatively resistant to spelling errors and knows how to cope with punctuation and accentuation of phrases (eg with the Shift key). However, speech synthesis lacks emotionality, and Tacotron 2 also has difficulties with foreign words.

It remains to be seen when this synthesizer and similar competing products will be available to a wider audience and if they can be used in Spanish. Meanwhile, screen readers for the blind and the visually impaired continue to use common speech synthesizers that still sound like machines.

Other fields of application of screen readers

Screen readers are not only used in the workplaces of blind people, but also serve as tools to help all those with reduced vision or people who cannot read. However, it can also be applied in other areas and situations: such is the case, for example, those moments in which a person performs a task that prevents them from reading a text at the same time. In these cases, screen readers become very practical elements as they read a text aloud while the listener is engaged in another activity. Let's look at some scenarios:

  • When traveling by car: screen readers can read texts aloud, be it scientific articles, news or guides, while driving.
  • Listen to texts from the smartphone : if you enter a text in a screen reader application, it can also read it aloud on the smartphone, for example, during a walk or during the journey to take public transport, something that is more comfortable than read text on a small screen.
  • Substitute for radio or listening to instructions at work : If you're doing a task that doesn't require your full attention, screen readers can take on the role of radio or podcast as an informational or entertainment medium. If you work with the help of manuals, this type of software can be helpful to read aloud each of the work stages.
  • Give your eyes a break : reading on the computer for several hours can tire your eyes, so it is important to alternate tasks by lying down for a while and listening to a text aloud. Specifically if working for hours with written texts, switching to an acoustic medium can increase attention again.

The problem of Internet accessibility

For people in wheelchairs it is currently important that buildings are as well equipped as possible, either with ramps or elevators. This same principle is also valid for the Internet and, so that people with visual disabilities can navigate the Internet without barriers, some rules must be followed . This is collected internationally in the Web Content Accessibility Guidelines, (WCAG or Guides or Web Content Accessibility Guidelines). At the national level, Royal Decree 1494/2007, of November 12, can be consulted, which highlights certain criteria of accessibility and non-discrimination regarding the use of technologies, products and services of the information society and of the social media.

The term? Internet without barriers? It not only refers to the construction of web pages adapted to the disabled, but also to the fact that the contents and texts have an easily accessible structure . Also, accessibility across various operating systems and platforms is another feature of the barrier-free Internet. At best, web pages are designed to be intelligible to people of different social and age groups and even non-native speakers, which can be difficult to achieve depending on the topic.

Barrier-free design on the Internet is not, however, a no-brainer. Modern, dynamic web pages present as much of a problem for screen readers as those powered by Flash, JavaScript, or graphics. Furthermore, in many content management systems (CMS) it is criticized that the resulting web pages present real accessibility problems. Often, some of the perception barriers on the Internet stem from poor color contrasts, lack of scalability, and textual alternatives to images, since without these alternatives, blind users can only explore web pages incompletely.

Reading with screen readers: most common problems

If web pages have barriers, screen readers for the blind cannot work efficiently, so they only deliver inconsistent results that even the most experienced screen reader users barely understand. The most common difficulties arise when reading the following items:

  • Graphics: If the web designer does not provide alternative text for graphics, screen readers skip the content of the graphics. If a graphic is relevant to the meaning of the text or the text refers directly to the graphic, the user of this screen reader software will have trouble understanding it. Alternative texts for images can be easily integrated using HTML code and when read aloud by screen readers, visually impaired people can tell what the images contain. If the graphic is also accompanied by an additional link, it is important to refer to it in the alternative text.
  • Tables: If tables are not organized in a systematic and practical way, reading them can cause some confusion. Many screen readers make it easier for users to understand tables, although no program can compensate for the fact that they are not made correctly, for example when the tables do not have clear rows or well defined columns.
  • Text composition / text code: when there are some text formats such as bold or italic, which are relevant to the meaning of the text, not all screen readers can deliver adequate results. Likewise, the absence of headings and subtitles in the code can make it difficult to navigate with the help of screen readers. However, if you write clean programming code with HTML and CSS and create an understandable textual structure, it will make it easier to read content with screen readers and navigate web pages for people with visual impairments.
  • Hidden content: on some pages, some content may only be shown if the user performs an action. For example, interactive buttons can enlarge text that was previously hidden. Sometimes, screen readers are not able to recognize this type of text or the text is reproduced in the wrong order because the software used as a scren reader reads it even if the corresponding buttons are not activated. In general it can be said that this type of software has problems with texts or very complicated web page structures.
  • Frames: If a web page does not assign clear titles to the frames, only the mere content of the frames will be read (e.g. the navigation bars). This makes navigation considerably more difficult for users with low vision. Thus, related texts should be part of a single frame and, at best, web pages should dispense with subdivisions in frames. All in all, frames are used relatively little.
  • Forms: the fields must contain clear labels so that screen readers can perform their function correctly, in addition to being able to be handled easily with the keyboard.

The most popular screen readers

NVDA: free screen reader for Windows

NonVisual Desktop Access, NVDA abbreviated, stands out for its very easy startup and handling and is especially recommended for those who are just starting to use this type of software. NVDA supports both synthetic speech output, which reads text aloud, and translation with the help of braille writing. The program is open source and funded by donations, although it is constantly being developed and is also compatible with all versions of Windows from 7 (Service Pack 1). However, the manufacturer recommends using it with Windows 10.

NVDA has the following features:

  • It supports the most common browsers, email, chat and Microsoft Office programs such as Word and Excel. In addition, NVDA also supports the Windows command interpreter and console applications.
  • It consists of a single .exe file (approx. 50 MB) that can also be loaded from external storage media such as USB sticks. The installation tool is intuitive.
  • Many simple keyboard commands help when navigating content such as web pages, turning NVDA on and off, and pausing the read-aloud process.
  • The speech synthesizer emits texts in 44 different languages ​​and the pre-installed synthesizer is eSpeak, free to access. NVDA also allows the integration of SAPI 4 and SAPI 5.
  • This screen reader recognizes and indicates different textual formats.
  • Supports mouse functions such as? Mouseover ?.
  • Supports many braille lines.

JAWS: free screen reader for Windows

Job Access With Speech, better known as JAWS, is Freedom Scientific's paid screen reader. The first version of the industry leader in screen readers for the blind was developed for MS DOS in 1989 and is so far with the current version JAWS 2018 the most popular electronic assistive tool for the blind and visually impaired. JAWS is available for all current versions of Windows and is extremely stable and efficient. To verify this, you can use a trial version that works fully for 40 minutes, but to continue using the software it is necessary to purchase a paid license. In Spain there are several providers that offer it and depending on the license, the costs range between 1,000 and 3,000 euros, which makes the rate model anything but transparent. However, in view of these costs and that in Spain screen readers are considered a means of help for the disabled, before purchasing it is advisable to find out if there are subsidies in this regard.

The JAWS features are:

  • Powerful voice synthesizer called Eloquence capable of reproducing 7 languages ​​(Spanish, English, German, French, Italian, Portuguese and Finnish). It supports RealSpeak, a synthesizer that sounds relatively natural.
  • Manuals written in braille make it easy to use JAWS. In addition, an auxiliary database and customer support are available on the Internet.
  • In addition to the most common text documents, this screen reader can also work with PDF and text linked to graphics and animations.
  • The quick navigation buttons and the list function allow for quick and comfortable Internet browsing.
  • It supports many internal Windows tools and services.
  • Supports most braille displays.
  • The voice-controlled installation allows the visually impaired user to carry out the process autonomously.
  • Support of numerous programs, such as Microsoft (Office), Adobe and current browsers. If you have specialized knowledge, JAWS can turn to special software.

Dolphin: paid screen reader for Windows

The Dolphin screen reader was marketed as SuperNova before receiving its current name from the developer Dolphin Computer Access Ltd. This software allows people who are blind and visually impaired to have complete control of the computer. The tool is available free of charge for 30 days, after which it is necessary to acquire a license. The price of this ranges between 1 000 and 1 300 euros, so it is advisable to find out if there are subsidies so as not to face all the costs on your own.

Dolphin stands out for the following characteristics:

  • ? Vocalizer Expressive ?, more powerful and relatively natural-sounding speech synthesizer. It offers configuration options for voice, melodies and speed. According to the provider, its many configuration possibilities allow you to create your own voice broadcast.
  • Quick navigation through keyboard commands, quick change of items.
  • Search function to navigate faster between web pages.
  • This screen reader can examine the format of documents and thus provide indications on the? Text style? so that the document's readers can also view it correctly. Dolphin also helps to set font size and type, bold, italic, and underline, among others, but it is also capable of selecting and reading PDF documents aloud.
  • ? Dolphin Cursor? simulates a mouse through keyboard commands, which can be useful for users who do not handle it very well.
  • Support of more than 60 braille lines.
  • With the setup wizard both blind and visually impaired people can configure the program independently.
  • Additional eBook support.

Narrator: Windows' internal screen reader

Windows versions 7 through 8.1 have an internal screen reader. Enter? Narrator? in the search bar and run the program. This is done in Windows 10 with the combination of? Windows key + CTRL + Enter? (on a touch screen lightly touch with 4 fingers) The process will then immediately run in the background. If you double-click on the tool symbol, several options will appear.

image
The internal Windows tool is very simple and can help you become familiar with screen readers for the blind

The tool is very simple: it facilitates navigation using some keyboard commands and it reads texts without problems. However, the speech synthesizers it offers are outdated and do not meet today's quality standard. Supported synthesizers are not available in all languages. Thus, blind and visually impaired users must acquire more specialized software such as NVDA, JAWS or Dolphin in the long term. With this, the internal Windows tool is only recommended for those who want to have a first contact with a simple screen reader or for users with residual vision; in short, for those who do not completely depend on a screen reader.

VoiceOver: the pre-installed screen reader for macOS and iOS

VoiceOver allows people with complete or partial blindness to operate Apple systems with the help of voice and keyboard control to listen to content read aloud. The tool is pre-installed on macOS, making it an obvious choice for Apple users. To activate VoiceOver on macOS, click the? Command-F5 ?. It currently supports 26 languages ​​and is also available for iPad and iPhone systems (as of 3GS).

VoiceOver speech synthesizer is called from macOS X 10.5? Alex? and stands out for its power and for being very comprehensible, since, unlike older synthesizers, it is able to imitate the fluency of speech in a convincing way. Also,? Alex? it also stands out for integrating breath sounds to make the synthesizer appear even more authentic. Since macOS X 10.7, VoiceOver also supports the integration of RealSpeak voices from Nuance. Since the choice of speech synthesizer is a matter of taste, a wider range of options has added value for the user.

VoiceOver also supports most of the popular braille displays and offers keyboard and mouse control options. To simplify navigation, the program divides the content of the web page into elements that are read aloud. Interactive elements such as text fields and scroll bars can be controlled with the keyboard, and VoiceOver also offers suitable options for users of trackpads or touchpads.

Orca: the free screen reader for Linux

Orca is a free and open source screen reader for Linux that is constantly evolving thanks to a broad community and an active circle of developers. The program uses the eSpeak speech synthesizer, which generates a rather artificial language. For this reason, Orca specifically seeks out computer linguists who want to participate in the development of the synthesizer, but also uses international translators who make the program available in different languages, so Orca is a joint project .

It is extremely popular for its practical audio guides, which can be downloaded for free. With these, users can step-by-step into Orca and its functions, in which its integration into the Linux operating system also plays an important role.

The program is part of the GNOME platform (since version 2.16) and is usually accompanied by Ubuntu and Fedora. In addition, systems often contain synthesizers, braille displays, and zoom tools that Orca integrates automatically. In some cases, the user has to download these parts, which can make Orca difficult to integrate.

ChromeVox and Chirpy: screen readers as browser extensions

Some browser extensions also allow you to read texts aloud, as they are small programs developed specifically to read web pages. ChromeVox for Google Chrome and Chirpy for Firefox are two free reading programs that can be quickly installed in both browsers.

Both applications work through small buttons in the browser window, through which the previously marked text fields can be read aloud. While Chirpy's speech synthesizer sounds nice and quiet, ChromeVox's speech output is found by many to be a bit irritating and overly loud. In terms of quality, neither of the two synthesizers can compete with the voice programs of the? Real? screen readers.

Browser extensions cannot completely replace screen reader software , specifically because users with a high visual impairment are subject to good manageability, a feature lacking in add-ons for browsers. These are rather interesting for users without a severe visual impairment and who want to use them without much effort to read texts aloud.

TalkBack: screen reader for Android

TalkBack is installed on most Android devices and can be activated and deactivated in the? Accessibility? Section. (? Accessibility?). This free service makes it possible for the blind and visually impaired to use their Android device without problems. The app runs in the background and plays the texts synthetically, as well as including acoustic signals and vibration feedback.

image
You can disable TalkBack in Android settings

Here's how to activate TalkBack:

  • Go to the app menu in your smartphone settings and scroll down.
  • In the tab? Settings? (? Settings?) Is the category? Accessibility? (? Accessibility?).
  • TalkBack will appear in? Services? when installed. If it isn't already, you can download it for free from the Google Play Store.
  • In the TalkBack window you can activate or deactivate the app using the slider.
  • In the section? Accessibility? (? Accessibility?) There is the function? Listen Selection ?, which is useful if you only want to listen to the texts of your choice. Once TalkBack is activated, you can ignore the "Listen Selection" option.

TalkBack is permanently on , which can cause delays on some devices . This screen reader is recommended especially if it is combined with a high-performance smartphone. Loading delays especially affect blind users, as they cannot easily recognize this slowdown and sometimes consider themselves to be responsible for the errors even if it is due to a technical problem. All in all, TalkBack is a very compelling program, although it does require the devices to have some power to run smoothly.

ShinePlus as screen reader for Android

If you're experiencing problems with TalkBack or just want to try an alternative, Shine's screen reader, also known as? ShinePlus ?, is an option worth considering. The tool is free, can be downloaded from the Play Store, and is ad-supported. Once installed, it will appear in the "Accessibility" section, from where it can be activated.

While the app is running, a simple touch on the touch screen will describe the selected area, thus allowing the buttons to be explained or the textual elements read aloud. To use the phone functions as well as to navigate, it is necessary to double click on each icon. In addition, ShinePlus offers a magnifying glass for users with reduced visibility. However, icon recognition is still immature, especially in the case of more complex applications. Hotspots are often not recognized, making them impossible for blind people to operate. In comparison, TalkBack, a screen reader for Android, enables better handling with web content and user reports indicate that it is more fluid than the Google app, which is an advantage for weaker devices, but the audio signals ShinePlus are less obtrusive.

Screen reader comparison

Program OS Price Advantage Drawbacks
NVDA Windows 7, 8.1, 10 Gratuitous Ideal for beginners, good speech synthesizers (eSpeak, Sapi 4/5), braille display support, constant development, 44 languages, a single .exe file Free speech synthesizers only (no modern synthesizer), no program support, somewhat heavy navigation
JAWS Windows 7, 8.1, 10 1,000 - 3,000 euros High-powered speech synthesizers (Eloquence, RealSpeak), extensive user support, reading PDF and graphics, optimal navigation for blind users, braille display support, compatible with numerous Windows and Office applications, market leader with a large community users Extremely expensive software, somewhat opaque payment model, only 7 languages
Dolphin Windows 7, 8.1, 10 1,000 - 1,300 euros Powerful and variable speech synthesizer (Vocalizer Expressive), search function, PDF reading,? Dolphin Cursor ?, support for braille lines, supports eBooks from some providers Expensive software, limited online support, small community
Windows Narrator Windows 7, 8.1, 10 Pre-installed Good for getting started with screen readers, easy text reading, easy navigation with keyboard commands, native Windows integration The speech synthesizer sounds very mechanical, so it is not suitable as a comprehensive solution for people with blindness, somewhat reduced language support, does not support braille lines
Voiceover macOS, macOS X, iOS Pre-installed Very good to start with, relatively high-performance speech synthesizers (Alex and RealSpeak), support for braille displays, good navigation through keyboard commands, considerably facilitates the use of smartphones and tablets Only free speech synthesizers can be used (no modern synthesizer), does not offer support for different programs, not suitable as a comprehensive solution for the blind
Killer whale Linux (GNOME) Gratuitous Relatively powerful speech synthesizer (eSpeak), braille display support, good navigation via keyboard commands, open source, community project, audio guides Partially complex setup, only free speech synthesizer (artificial sound)
ChromeVox Google Chrome Gratuitous Simple integration in the web browser, for occasional users Poor speech synthesizer, not suitable as one-stop solution for the blind, no regular updates
Chirpy Mozilla Firefox Gratuitous Simple integration in the web browser, for occasional users Poor quality speech synthesizer, not suitable as a one-stop solution for the blind, some performance issues, no regular updates
TalkBack Android Gratuitous It considerably facilitates the use of the smartphone, the developer (Google) makes important advances in the aspect of the artificial language Requires a lot of resources and powerful hardware, weaker speech synthesizer
ShinePlus Android Gratuitous Facilitates smartphone handling considerably, saves more resources than TalkBack Weaker speech synthesizer, advertising, irregular updates, presence of some bugs

...