Making your Page Sound Accessible
In the U.K., 65% of disabled people use the Internet1. That makes 8 million disabled users in the U.K. alone, and many more from other developed nations. Such numbers completely justify making an extra effort to improve your website for the visually impaired so that they may access your information or utilize your service, and hopefully they will reward the extra effort. There are a few methods for this, from simply practical to deeply technical.
The visually impaired use text readers when accessing websites, and it makes sense to provide text copies of all your content. These should be written in coherent English and short sentences so that they don’t need to go back and listen to it again. Providing an alternative to images will reduce the load time of the pages, as text is much smaller in size than pictures. Furthermore, Googlebot mainly indexes text so the improvement will have an SEO benefit as well.
Less text input will mean quicker browsing and make your page sound accessible. Avoid relying on the search function in these cases, as it will prove to be clumsy and unpopular. Menus could face a similar fate if not designed to be used with read-out-loud applications like Microsoft Narrator. Try to position your links in such an order as to make sense when the reader application goes over them. Alternatively, images can be optimized by providing an accurate item description and fully utilizing the alt attribute. Not surprisingly, these are all also characteristics of good SEO.
The more advanced method includes aural style sheets, which are part of CSS2. This will make the site fully accessible to screen readers and completely audible. As an added bonus, the site can be used from other devices such as automobiles, learning computers and home entertainment systems. The interface allows for three-dimensional sound as well as specified playing times in accordance with other actions. The synthesized speech has multiple customizable options such as style or volume.
The volume can be set as either a nominal value of 0 to 100 or a percentage from the set volume of the computer. Certain commands exist like “x-soft,” “soft,” and “x-loud,” which all match to the previous scale. Additionally, the speech style can be customized with or without rendering. The two most common rendering options are “normal” with standard pronunciation rules, and “spell-out” where the interface spells out letter by letter.
CSS2 further offers the option to space out content reading with its three pause functions. It specifies how much time should pass between elements for clearer understanding of the content. Naturally, pauses alone cannot distinguish separate elements, so adding elements or short audio files (auditory icons) to be played before or after the elements will make the page run more smoothly. For a more dramatic effect, the aural style sheets enable sound to be used as background to the reading. You can even mix sounds, create repetitive noises or use keywords to trigger the specific noises.
For more professional reading, CSS2 emulates voices positioned in different locations in space, in front of, behind, to the left or right of the speaker, or with azimuth and elevation properties. By adding degrees to the sound, the listener can better distinguish from the two multiple sources.
Finally, the CSS2 supports different voice characteristics. It enables gender and age-specific voices such as male, female, and child, and more specifically speed and pitch (high and low in frequency). The voice richness will determine whether the voice will be audible in large or small rooms. The interface can be configured to pronounce punctuation or to be rendered as part of the text.