Interregional Seminar and Symposium on
International Norms and Standards relating to Disability,
REPORT Index : Annexes :
I. II. III. IV. V. VI. VII. VIII. IX. X.

Annex VII

Access with Speech and Braille for Chinese Windows 98 - ASAB 98V1.1^[154]

Presented by: Dr. LU Qin, Associate Professor[155]
The Chinese Computing Laboratory, Department of Computing
The Polytechnic University of Hong Kong (SAR)

Introduction

The Department of Computing, Hong Kong Polytechnic University, in collaboration with the Hong Kong Society for the Blind has developed the first general-purpose Chinese computer interface for the visually impaired, the Access with Speech and Braille for Chinese Windows 98 (ASAB 98v1.1).

ASAB 98 is an add-on software to help the visually impaired to access Microsoft Windows and its applications. It provides both the Cantonese and English voice output as well as Cantonese and English Braille input and output. Instead of producing a specialized word processing software which can only be used by the visually impaired, ASAB 98 enables a totally blind person to handle Chinese processing with the regular Microsoft window’s graphic user interface (GUI) environment. It allows the visually impaired person to work with the commonly used Chinese Windows 98 applications for the sighted, such as Microsoft Word and Excel, etc. with only an additional speech synthesizer and/or Braille device. This system can greatly help the visually impaired persons to use computers comprehensively, to increase their job opportunities, and to enhance their quality of life. Most important of all, it increases their ability to integrate into the mainstream of society. Previously, visually impaired persons could only make use of a few stand-alone software packages especially developed for them in order to do simple Chinese word-processing.

Background

For nearly three decades, the visually impaired have been using computer with synthetic speech output or refreshable Braille display devices in industrialised countries. They were engaged at first with large mainframes mainly in computer programming. Subsequently, with the booming growth and popularity of personal computers (PC) from the late 1970s, many more joined in and job categories soon expanded to cover all areas of electronic data processing. However, when the new graphic user interface environment was first introduced, and later popularized by the Microsoft Windows platform, it brought some unforeseen problems for the visually impaired. Fortunately, many resources and much effort have been poured into the development of programs that can interface with Windows and initial success has been witnessed with the release in 1992 of a Windows bridge program, which enabled the use of Windows via voice synthesisers. Subsequently, the program was upgraded to support Braille equipment.

The visually impaired in Hong Kong began to use computers in the early 80’s. However, since output devices for the visually impaired are produced in the West such as “Screen Power” developed by Telesensory and “Jaws” by Hunter-Joyce, these products do not support Chinese input/output. Adding the ability to handle Chinese for the visually impaired on the Windows platform is not trivial because of the intrinsic differences between Chinese and English Braille systems for the blind.

Braille is a touch-reading system for the blind. It is named after the blind French inventor, Louis Braille. Since its inception in the early 19th Century, a total of 64 Braille symbols were available, each consisting of a maximum of 6 raised dots, in a 2-column by 3-row matrix, known as a cell. In the 80’s, most Braille equipment was capable of producing 8-dot Braille. By adding one more row of two dots to the bottom of the existing cell, a total of 256 symbols can be formed. The Braille system for western languages, such as English, is alphabet based. That is, each letter has a Braille code and the input of English for the blind is through spelling just like other keyboard input.

Due to the ideographic nature of Chinese characters and the sheer size of the Chinese character set (more than 13,000 for traditional Chinese in “Big5 encoding”), Chinese Braille input and output simply cannot be character based. Instead, Chinese Braille systems are phonetic-based. Each Chinese phonetic symbol usually is composed of 3 letters, representing the initial consonant, the vowel and the tone, respectively. However, in practice, Chinese words formed by only 2 symbols, or even one, are common. Therefore, “variable length” is a regular feature in Chinese Braille. Due to being phonetic-based, different dialects would have their own specific phonetic Braille encoding systems, such as Cantonese and Putonghua.

Some preliminary work has been initiated by mainly volunteers in Taiwan (Province) and the People’s Republic of China to develop suitable systems for visually impaired persons to handle Chinese. Progress has been slow and most of the focus has been on Mandarin. More importantly, the existing systems are stand-alone word processing editor software customized for the visually impaired. Blind people in Hong Kong and other parts of China cannot enjoy the full access to various software packages, which have long used by the visually impaired people in the West. The availability of ABAS 98 made it possible for the visually impaired to enjoy the same accessibility to different software in Microsoft Windows ® environment.

The project was funded for the last three years by the Hong Kong Jockey Club, supplemented by Polytechnic University of Hong Kong (SAR) internal funds.

System requirements

Base system requirements are as follows:

Pentium 200 MHz IBM (compatible) PC
64MB RAM (suggest 128MB RAM)
Sound card
Microsoft Chinese Windows 98
CD-ROM
At least 45MB hard disk space
Braille Display out put device (optional)

System functional components

The system is composed of four functional components:

Voice (Cantonese and English) output module for Windows Interface;
Output module to support Braille device;
Input module using Cantonese Braille encoding scheme via regular keyboard;
Real-time conversion between “Big-5 encoding” and Cantonese Braille encoding.

To put it simply, ASAB 98 can be considered to be a Microsoft Windows browser. It can obtain the name of an icon or software, and out put it in Cantonese or English. The system provides different control keys to indicate the current system state or switch to different working mode, for example, switching from input mode to the volume change mode of the speaker. In terms of input, the system provides Cantonese/English Braille input through the keyboard. For Chinese, the input can be a single character, a single word, or a whole sentence. In all cases, assistance through voice/Braille is provided to resolve the ambiguity caused by different characters with the same pronunciation.

The system provides an intelligent code converter between Big-5 and the Cantonese Braille. The converter is vital to the system because a Braille coded document can only be understood by trained eyes/hands. In order to work in a common environment, Braille input method produced documents must be converted to Big-5 before exchange can take place. To avoid confusion, all documents are stored in Big-5 internally so that they are ready to be used by anyone. Output to Braille code and Cantonese voice output are done in real-time.

ASAB 98 vi1.1 requires continued improvement. We sincerely hope to receive feedback from its users, and we welcome all suggestions for its further improvement.

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[154] Products mentioned are trademarked / registered by the respective owner / manufacturer.

[155] celuqin @ comp.polyu.edu.hk or cclab @ comp.polyu.edu.hk ; facsimile ++ 2774-0842.