Web Accessibility Issues For Visually Impaired Computer Science Essay

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HCI: (Human-Computer Interface), the term HCI means how humans interact with and to what level computers are developed for successful interaction with human beings. A significant number of major corporations and academic institutions are now studying HCI.

WWW: World Wide Web has revolutionized the way people share and transmit data. As we talk about interaction, there are number of issues reported with interaction of humans with computers. Therefore, developers aims to build an interactive systems that are easy to access usable and most of all easy to navigate. Our main concern in this report is to identify the issues reported by the users with disabilities with web accessibility.

DISABILITY: The term "disability" means inability to perform an activity because of some physical or mental disorder. This can range from minor to major. A number of researches has been conducted to find out the range to disabilities however, as a result from minor to major, it refers to a wide range of physical and mental conditions which prevents users to do specific task. However, each property is further sub-divided into more complex nature with variation/severity of levels. For World Wide Web, we have some standards which may vary from country to country. Disability itself can be sub-categorized in severity and it can be from one-to-many in a single person.


In this report we are going to discuss web accessibility issues related to people with commonly known visual disabilities, for this we will critically evaluate the possibilities of web accessibility solutions. Due to the nature of this report and topic we have chosen "YouTube" as a part of our case study.


YouTube a well known media website developed and owned by Google inc. Video websites, such as YouTube, allow users to make, upload and share video contents to other internet users. There is lots of accessibility issues reported. We will discuss one of the main problems of YouTube in view of accessibility by visually impaired users. Users in this site customize their profile according to their needs. It can be image, video or text as a comment or information to provide with a particular video stream.


In this section we are going to discuss some of the most commonly known accessibility issue for web sites that users with different visual disabilities may encounter. According to the World Wide Web Consortium (W3C, 2005) visual disabilities can be sub-categorized into three different groups, commonly known as Color Blindness, Low Vision and Blindness.

2.1 Color Blindness

The term color blindness refers to describe people with a defective color vision (Benyon, Turner and Turner 2005b). Commonly known issues of this type of disability is the difficulty to distinguish between red and green. In worst case scenario, it can also be described as an inability to detect any color. According to recent statistics and surveys, color blindness is more prevalent among males then females. If we look on YouTube, we can see that there are millions of media content posted everyday that can be a bit problematic for users of this type of disability. However, in YouTube's case it is much more difficult to sort each page according to the needs of these users. If we look on the layout of the website we can see that there are some text fields, as this websites aims to deliver media content therefore, one cannot ignore the importance of text. Some users with visual disabilities use browsers to turn off the style sheet, while others can override them with their own style sheets. It is not possible in YouTube because this site contains more than just text. It includes images, video, and text. As we have discussed that user with color blindness cannot distinguish between colors red green or yellow or even not at all so a combination of background and font color can seriously reduce the ability to read the entire content that is available on the site.

2.2 Low Vision

The World Wide Web Consortium (W3C, 2005) refers the people with low vision has having poor acuity. This form of deformity is also described as blurred vision or a clouded vision. It can be further sub-divided into two main categories, a tunnel vision and central field vision. A tunnel vision can be described as a person who can only see the middle of the visual field, while, the central field vision is specified as a person only able to see the edges of the visual field. However, this problem often makes them very hard to navigate through the website because a person with low vision often uses magnifiers for a clear view of the content displayed on the screen, but magnifying is not always the useful way because some websites don't have the ability to enlarge the fonts or in other words they don't use appropriate style sheets. This type of functionality can be achieved from web browsers nowadays although the quality of the content is not always the same. Operating systems such as windows have a built-in facility to use magnifier but it also reduces the possibilities for the user to access the require information.

2.3 Blindness

A severe yet one of the most serious form of visual disability is often describes as blindness. The term "blindness" refers to a substantial, uncorrectable loss of vision in both eye" (W3C, 2005). Apart from low vision and color blindness, users who are blind normally access the information on the web using screen readers. A screen reader is a software application that attempts to identify and interpret what is being displayed on the screen (or, more accurately, sent to standard output, whether a video monitor is present or not). This interpretation is then re-presented to the user with text-to-speech, sound icons, or a Braille output device (Wikipedia). Blind users find it difficult to read pages that include web text contents that are not properly marked up with columns and row headers. Screen readers cannot read images, videos and graphs that are not proper described. Later in this report we will look further on how non-visual users interact on our chosen system.

Before we move further, we would like to take a look on some of the most important words used in this report in order to fully understand the key issues that are going to be discussed.


2.4(a) ALT TEXT: An HTML attribute use to provide a hidden text description of an image or a part of the image. It is the description in text when we hold our mouse cursor over the image or text field.

2.4(b) FLASH: Flash animations are embedded into the web sites that can be viewed by browsers with the help of plug-in

2.4(c) FRAMES: Also describes as the section of the web site which allows to divide the browser into many frames. Each frame is independent and may display and or update contents within the web site.


In this section we are going to highlight some of the key issues of YouTube and later on we will discuss it in the light of guidelines and standards set internationally to make web sites more accessible for visually impaired users.


This website uses flash content. Adobe flash (formerly macromedia flash) is a multimedia platform that is popular for adding animation and interactivity to web pages (Wikipedia). Flash contents are commonly used to integrate video into web pages. Video contents used in this website also plays a major role when we discuss about visually impaired users.

A user with color blindness finds it very difficult to navigate as the stream plays. An advertisement displaying discounts or special offers mostly contains red color which makes them to miss or ignore the entire content because of the inability to distinguish between colors.

However, on the other hand non-visual users cannot access the entire content because the screen readers cannot read videos. A video without an audio stream can be a bit problematic for blind users because they mainly rely on audio and without audio the whole process of accessing a particular video stream is useless

Users with low vision often finds it difficult if there is a text involved in a video or page in which they are really interested. Different factors can be the reason of different outcomes. But in text fields the use of font size or magnifying softwares plays a huge role specially when the font size is too small to read. There are some cases in which the video stream is so fast that even a normal user cannot process the information however, a user with low vision has to pause and play the media content in order to access the content. It can take even longer is that particular stream includes text and images for example, charts, product details and scrolling text.


YouTube offers a feature in which users can customize their profile with colored text, background and profile/ID images commonly known as AVATAR. It is essential to be aware of the facility when we talk about individuals with color blindness because the use of text that insufficiently contrasts with the background color can really make the page difficult to read for color blind users

Non-visual users can face accessibility issues if the images are not properly described however, we do not see any kind of feature that can allow normal users to add description to their image files for non-visual users to access hence, this makes it even more difficult to navigate through profile pages as the screen reader does not have the capability to read images without the help of ALT Text.


Usability is describes as how easy a system or product is to use. For this we have the international standard of ISO 9241-11 which provides us the guidelines for usability and define it as a level to which users in given circumstances may access a product to achieve specific objective in an effective and satisfying way (usability Partners, 2009)

World Wide Web Consortium (W3C) is an international consortium that develops standards and guidelines for internet which aims to make the website more accessible to all regardless of any circumstances of lie. Standards of accessibility and usability are according to Yates (2005), key elements of any good design practices. W3C has also started the web accessibility initiative (WAI) in which they work together with organization worldwide to develop guidelines, resources for developing websites to make them accessible to users with disabilities however, WAI has also produced web content accessibility guidelines which contains large amount of bother general and specific guidelines for increased accessibility of many web based technologies. This is however available to the website that focuses on what techniques should be used in order to achieve satisfactory results according to the guidelines.


In this report we will see why YouTube is not really a great website for visually impaired users.


As we have discussed earlier, flash animations can become a problem for the visually impaired because some readers generally cannot interpret flash animations, however there are newer types of readers that can interpret, but these are not particularly common since flash is a new technique (Holm and Tenhunen, 2004). By visiting profiles of different users in this website, the functionality of describing the contents can seriously reduced because in profiles the images used are not properly describes, in other words they lack the use of ALT text for screen readers hence making it impossible for a non-visual reader to take full advantage of their output device. It is also reported that in some cases where readers try to reader the content it actually crashes because of the auto-generated contents on this site as flash animations are also used for advertisement. The main reason behind this problem is the technological development of the aiding devices are not up to the standards of the web design. This can cause the user to skip the main part of the website. From the study above we came to know that flash cannot be considered as a user friendly for the visually impaired, this means that the majority of the accessibility on YouTube is sacrificed in the favor of visual effects. "Provide captions and alternatives for audio and video contents", This guideline holds with the exception of media content that is an alternative to text and that is clearly marked as such (World Wide Web Consortium, 2008). According to non-visual users, websites like YouTube which consists of media content, flash animations and images without proper description are very irritating.


Images and links without ALT Text, flash animations or empty frames and so called capture codes are the main problem today for the aiding devices. As we look further in YouTube options and functionality we saw that this site does not provide with any sort of audio links to the capture codes which means that a non-visual user cannot register itself as a fully privileged member. Capture codes are the sequel of randomly generated codes in image format which allows extra security which is used just to verify that an actual person is sitting behind the keyboard and not a automate program. Where this added security to the website , on the other hand it creates more problems for non-visual users as the absence of audio link is a serious issue since YouTube is the only online media sourced website which is accessed worldwide. Images with text also creates problem for the aiding devices to interpret. Guideline 4.1 Distinguishable of the WCAG (World Wide Web Consortium, 2008) states that images containing text should be avoided.

People with minor visual impairment can read printed text if the letters are big enough and he layout of the text is logical. Small text and small images are often difficult to see for all type of users. The contrast should be according to World Wide Web Consortium, 2008be at least 4.5:1 and should be able to enlarged a least twice the size without any help of the aids. However, for YouTube, the only way to read the text is to user magnifying softwares. Some of the newest browsers like Opera and Safari can magnify the entire content of the website. While, other browsers like internet explorer and firefox can only enlarge the text and leaving the surface of the page unaffected which can cause problems for both color blind and low vision users.


In this section we are going to discuss some of the approaches for resolving web accessibility issues as well as technologies that have been developed to help webmasters and developers to make the page even more accessible for visually impaired.

For websites YouTube, the web developer should follow the guidelines set by Adobe (2009), to make flash animation accessible which is also the part of the objectives of the guidelines 4.3 adaptable of the WCAG (World Wide Web Consortium, 2008). Flash animations should preferably be used as supplements along with the available guidelines.

Tables are common to websites where it divides the website contents. It is a simple alternative to frames as some developers want to avoid frames due to the problems associated with search engine and other frame related issues (Johansson, 2004). The developer should follow the standard for how frames should be designed. They should also avoid using too much Java scripts and applets. This is also against the World Wide Web Consortium, 2008 guidelines 4.1 compatible of the WCAG.

The functionality of the aiding devices for the visually impaired are often based on the standards of HTML and since YouTube consists of so many Java Scripts and applets, this makes them difficult to read and identify the content however, a proper and good layout would make the aiding devices easer to interpret in the right order and sequence as the aiding devices are far behind then the website technologies.

However developers often see themselves as a general users (Edwards, 1995) which according to (Molich, 2002) causes problem hence further limiting the needs of the visually impaired that want to use the web site. AS we have discussed earlier, the lack of audio link in YouTube for capture codes clearly indicates that the developer may have overlooked the needs of an actual user.

According to Yates (2005), there are three main points that inhibits accessibility on the internet. The first argument states that many organizations are not "interested in making website accessible". While the second argument continues to focus that "making websites accessible makes them boring". This statement is based on the belief which indicates that an accessible website does not have any graphic or other multimedia elements but in reality this is not the case as we study the third argument which is "we do not want to spend the money on it". Of course, working on too much accessibility will lead to the cost spend on a particular website but websites like YouTube lacks few accessibility issues which according to Molich (2002) writes that organization working together with users can actually reduce cost, unwanted and too complicated functions can be identified and removed or remade, which in the end can reduce maintenance and support costs. Ross (2002) points out