Tips and Software for Blind Linux Users
Speech and Braille CSombined
There is already speech (Emacsspeak
) and Braille (BRLTTY)
software, but no combined solution. This was the reason for me to start the
development of a combined version. Instead of reinventing the wheel, as much
as possible has been used from existing software:
- Is a program to control a Braille terminal. It supports different hardware
connected to the serial ports and gets the screen content from the kernel
(/dev/vcs to be more exact) or from a shared segment filled by screader
. Limited speech support in BRLTTY allows to read the current line when
you have a program that reads ascii from standard input and converts it to
- HADIFIX is a text to phoneme converter (for German language only), the
first stage of a text to speech converter, MBROLA is a synthesizer to generate
speech from the phonemes.
To create a complete speech solution, only some missing parts have to be added:
- It should be possible to control the speech output with the standard
keyboard, without using the keys on the braille terminal. This makes it
necessary to read all keyboard input by BRLTTY. Unfortunately, there is no
kernel interface for doing this. A small kernel patch (key-sniff
) adds this interface to 2.0.x kernels.
- HADIFIX and MBROLA are not designed for interactive speech applications. A
shell around these two, called Softspeech
allows flushing the audio buffer etc..
- BRLTTY has to be extended to use keyboard input. This is still under
construction, but you can already download the development snapshot, called
- The original version of freephone has a bug, a version without
that one bug can be downloaded:
Other Software for Linux
- Blinux: FAQ
- A general speech solution is Screader
- The Ultrasonix
project tries to bring X to blind users.
- Jos Lemmens has
written a parallel port version of BRLTTY.
- Another speech solution: Speakup
(a kernel patch for 2.1.125 and above)
Links to Vendors
- Henter-Joyce speech and Braille for Windows95
- MicroTalk, a synthesizer
- Dolphin, synthesizer und software
- ALVA, produces Braille terminals.
- Baum, located in Germany, sells hardware
How to Configure Programs for Speech and Braille
lynx, pine (under construction)