Braille ASCII

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Braille ASCII (or more formally The North American Braille ASCII Code, also known as SimBraille) is a subset of the ASCII character set which uses 64 of the printable ASCII characters to represent all possible dot combinations in six-dot braille. It was developed around 1969 and, despite originally being known as North American Braille ASCII, it is now used internationally.

Contents

Overview

Braille ASCII uses the 64 ASCII characters between 32 and 95 inclusive. All capital letters in ASCII correspond to their equivalent values in uncontracted English Braille. Note however that, unlike standard print, there is only one braille symbol for each letter of the alphabet. Therefore, in Braille, all letters are lower-case by default, unless preceded by a capitalization sign (dot 6).

The numbers 1 through 9 and 0 correspond to the letters a through j, except that they are lowered or shifted lower in the Braille cell. For example, dots 1-4 represents c, and dots 2-5 is 3. The other symbols may or may not correspond to their Braille values. For example, dots 3-4 represents / in Braille ASCII, and this is the Braille slash, but dots 1-2-3-4-5-6 represents =, and this is not the equals sign in Braille.

Braille ASCII more closely corresponds to the Nemeth Braille Code for mathematics than it does to the English Literary Braille Code, as the Nemeth Braille code is what it was originally based upon.

If Braille ASCII is viewed in a word processor, it will look like a jumbled mix of letters, numbers, and punctuation. However, there are several fonts available, many of them free, which allow the user to view and print Braille ASCII as simulated braille, i.e. a graphical representation of braille characters.

Uses

Braille ASCII was originally designed to be a means for storing and transmitting six-dot Braille in a digital format, and this continues to be its primary usage today. Because it uses standard characters available on computer keyboards, it can be easily typed and edited with a standard word processor. Many Braille embossers receive their input in Braille ASCII, and nearly all Braille translation software can import and export this format.

Most institutions which produce Braille materials distribute BRF files. BRF is a file that can represent contracted or uncontracted (i.e. grade 1 or grade 2) Unified English Braille, English Braille and non-English languages. [1] BRF files contain plain Braille ASCII plus spaces, Carriage Return, Line Feed, and Form Feed ASCII control characters. The spaces, Carriage Returns, Line Feeds, and Form feeds are sufficient to specify how the Braille is formatted. Previously BRF contained some additional specialized formatting instructions, but now BRF is formatted exactly like Web-Braille/BARD. [2] [3] BRF files can be embossed with a braille embosser or printed, read on a refreshable braille display, or imperfectly back-translated [4] into standard text [5] [6] which can then be read by a screen reader or other similar program. Many find BRF files to be a more convenient way to receive brailled content, and it has increasing use as a distribution format. [7] If a SimBraille font [8] is downloaded and installed a BRF file can be opened in WordPad, Apache OpenOffice, Microsoft Word, Apple Pages, etc., and the Braille will appear correctly rendered as 2 dimensional, non-tactile, visual 6 dot braille characters when the font is set to SimBraille.

Unicode includes a means for encoding eight-dot braille; however, Braille ASCII continues to be the preferred format for encoding six-dot braille.

Braille ASCII values

Standard Braille 6-dot order . Braille cell.svg
Standard Braille 6-dot order .

The following table shows the arrangement of characters, with the hexadecimal value, corresponding ASCII character, binary notation matching the standard dot numbers (see the image on the left), Braille Unicode glyph, and general meaning for English (the actual meaning may change depending on context). [10]

ASCII hexASCII glyphBraille dots
(1 to 6)
Braille glyphUnicode Braille glyphEnglish
Braille
meaning
20 (space) 000000 Braille NULL.svg (space)
21 ! 011101 Braille E.svg the
22 " 000010 Braille ContractionPrefix.svg (contraction)
23 # 001111 Braille NumberSign.svg (number prefix)
24 $ 110101 Braille E.svg ed
25 % 100101 Braille SH.svg sh
26 & 111101 Braille AND.svg and
27 ' 001000 Braille Apostrophe.svg '
28 ( 111011 Braille A.svg of
29 ) 011111 Braille U.svg with
2A * 100001 Braille A.svg ch
2B + 001101 Braille O.svg ing
2C , 000001 Braille CapitalSign.svg (uppercase prefix)
2D - 001001 Braille Hyphen.svg -
2E . 000101 Braille DecimalPoint.svg (italic prefix)
2F / 001100 Braille ST.svg st or /
30 0 001011 Braille QuoteClose.svg
31 1 010000 Braille Comma.svg ,
32 2 011000 Braille Semicolon.svg ;
33 3 010010 Braille Colon.svg :
34 4 010011 Braille Period.svg .
35 5 010001 Braille QuestionMark.svg en
36 6 011010 Braille ExclamationPoint.svg !
37 7 011011 Braille Bracket.svg ( or )
38 8 011001 Braille QuoteOpen.svg “ or ?
39 9 001010 Braille Asterisk.svg in
3A : 100011 Braille U.svg wh
3B ; 000011 Braille Correction.svg (letter prefix)
3C < 110001 Braille E.svg gh
3D = 111111 Braille E.svg for
3E > 001110 Braille A.svg ar
3F ? 100111 Braille O.svg th
 
ASCII hexASCII glyphBraille dots
(1 to 6)
Braille glyphUnicode Braille glyphEnglish
Braille
meaning
40 @ 000100 Braille Accent.svg (accent prefix)
41 A 100000 Braille A1.svg a
42 B 110000 Braille B2.svg b
43 C 100100 Braille C3.svg c
44 D 100110 Braille D4.svg d
45 E 100010 Braille E5.svg e
46 F 110100 Braille F6.svg f
47 G 110110 Braille G7.svg g
48 H 110010 Braille H8.svg h
49 I 010100 Braille I9.svg i
4A J 010110 Braille J0.svg j
4B K 101000 Braille K.svg k
4C L 111000 Braille L.svg l
4D M 101100 Braille M.svg m
4E N 101110 Braille N.svg n
4F O 101010 Braille O.svg o
50 P 111100 Braille P.svg p
51 Q 111110 Braille Q.svg q
52 R 111010 Braille R.svg r
53 S 011100 Braille S.svg s
54 T 011110 Braille T.svg t
55 U 101001 Braille U.svg u
56 V 111001 Braille V.svg v
57 W 010111 Braille W.svg w
58 X 101101 Braille X.svg x
59 Y 101111 Braille Y.svg y
5A Z 101011 Braille Z.svg z
5B [ 010101 Braille O.svg ow
5C \ 110011 Braille U.svg ou
5D ] 110111 Braille I.svg er
5E ^ 000110 Braille Currency.svg (currency prefix)
5F _ 000111 Braille CursiveSign.svg (contraction)

The following shows the "ASCII glyph" under the associated Braille dots pattern from the table above, sorted according to the reverse lexicographical order of "Braille dots" patterns. It may be used to encode the above table. (Note that Unicode Braille characters are U+2800 through U+283F, with their code points being in reverse lexicographical order of the above table's "Braille dots" column, and that the symbol at top of the first cell is not an ASCII space but the empty Braille symbol U+2800):


 

A

1

B

'

K

2

L

@

C

I

F

/

M

S

P

"

E

3

H

9

O

6

R

^

D

J

G

>

N

T

Q

,

*

5

<

-

U

8

V

.

%

[

$

+

X

!

&

;

:

4

\

0

Z

7

(

_

?

W

]

#

Y

)

=

Unused ASCII values

Only 64 characters are needed to represent all possible combinations of 6-dot braille (including space), so not all ASCII values are needed for Braille ASCII.

The 26 Basic Latin lower-case letters (a to (z) are not normally used, but might be interpreted as having the same dot patterns as their 26 upper-case equivalents. The 5 other printable ASCII punctuation characters (`, {, |, }, and ~) are not used and their Braille ASCII rendition is not defined.

Braille ASCII is merely a subset of the ASCII table that can be used to represent all possible combinations of 6-dot braille. It is not to be confused with the Computer Braille Code, which can represent all ASCII values in braille.

See also

References

  1. "World Braille Usage".
  2. "New BARD Overview". nlsbard.loc.gov.
  3. "NBP - What's a BRF". www.nbp.org.
  4. "Liblouis* - An open-source braille translator and back-translator". liblouis.org.
  5. "About Electronic Files - APH Louis - APH Louis". louis.aph.org.
  6. "What are DAISY and BRF? - Bookshare". www.bookshare.org.
  7. "IRS Tax Forms (in Braille and Text Formats) - Internal Revenue Service". www.irs.gov.
  8. "BRL: Braille Through Remote Learning". www.brl.org.
  9. "Representing and Displaying Braille". DotlessBraille.org. February 20, 2002. Retrieved August 9, 2009.
  10. Halleck, John (August 24, 2000). "braille-ascii.ads". Braille.Ascii. Archived from the original on June 13, 2010. Retrieved August 10, 2009.