SignWriting Image Server Open Font and Rendering Software

Beta 5c

Copyright 2007,2008,2009 Stephen E Slevinski Jr. Some Rights Reserved.
Except where otherwise noted, this work is licensed under
Creative Commons Attribution ShareAlike 3.0


Dedicated to my wife Sonia, to Valerie Sutton and to the entire SignWriting List:
their support and encouragement has always been there.
Dedicated to all lovers of the written word,
especially Mortimer J. Adler who taught me how to read a book.
There have been too many other teachers and friends to name them all.

Contents

• History
• SignWriter DOS
• SignPuddle
• Open Standards

• Symbol
• Cluster
• Column
• Sort

• ISWA 2008
• Character Encoding Model
• Data Stream
• Token Stream
• Unicode Integration

• PHP
• JavaScript

• Data Stream
• PHP

• PHP

• Organization
• Function

• SignBox
• Special Commands
• SignSpelling Sequence

• Data Files
• Font Files
• License Files

Preface

The vision of the SignWriting Image Server is to provide tools to view and edit Binary SignWriting. SWIS can and should be used to generate test data, verify image display, and model behavior for implementations with other programming languages on any platform. The SymbolPalette and SignMaker are currently available as part of SWIS. SignText is in development and will be available in Release Candidate 1.

This project is about open standards. We are using the GPL v3, the Open Font License, and Creative Commons (by-sa).

Acknowledgments

1. SignWriting

History

SignWriter DOS

SignWriter was a breakthrough application for SignWriting because it not only made it possible to use SignWriting on computers, but it created a method for touch typing with sign language.

SignPuddle

The International MovementWriting Alphabet (IMWA) was originally designed as a huge repository for the symbols of SignWriting and DanceWriting. SignPuddle offered unrestricted access to the entire IMWA. This made it possible to use a larger symbol set than was previously available.

Open Standards

In 2007, Valerie undertook a huge effort to revamp and restructure the IMWA so that it focused exclusively on SignWriting. The resulting International SignWriting Alphabet (ISWA) is the most extensive and well organized symbol set in the history of SignWriting.

The ISWA 2008 is available under the Open Font License. This SignWriting Image Server project is available under the GPL v3.

2. Script

Symbol

Each SymbolGroups has anywhere from 5 to 58 BaseSymbols. Each BaseSymbol can have up to a maximum of 96 valid symbols. Valid symbols only occur for both valid fills and valid rotations, based on BaseSymbol. There are 6 possible fill values and 16 possible rotation values.

Cluster

The major difference between SignWriting and other scripts is that SignWriting is spatial, and not sequential. Either left to right, or top to bottom, almost all other scripts put one character after another. The symbols of SignWriting are written spatially. Each sign, like a word, is written based on spelling rules. One writing symbol is used as the artistic center of the sign and the other symbols relate or revolve around that artistic center spatially.

The visual center is different than the artistic center. The visual center is based on the symbols used in the writing. The visual center of a hand shape is the absolute center of the image, while the artistic center would be the center of the palm. The visual center of a sign is the visual center of the sign image, taking an average of the min and max coordinate values. However, if a sign contains 1 or more centering symbols, only the min and max coordinates of centering symbols are considered, and the coordinates of all non-centering symbols are ignored.

Therefore, each sign is made up of writing symbols spatially arranged on a 2 dimensional canvas. The canvas has a defined visual center and a subjective artistic center. Neither punctuation nor sorting symbols are allowed in a cluster.

Column

Sort

3. Binary SignWriting

ISWA 2008

The ISWA 2008 defines 30 SymbolGroups, 639 BaseSymbols, and 35023 symbols.

Character Encoding Model

The first BaseSymbol is assigned a character code of 256. Each BaseSymbol can have a maximum of 96 symbols (6 fills and 16 rotations). The next BaseSymbol is assigned a character code of 256 + 96.

This encoding results in a starting code of 256 and a maximum code of 61599. A range of 61343 values for 35023 valid codes.

Number characters are defined as having unique character codes. This avoids character collision when parsing. The spatial aspect of sign language data requires coordinated information. Each spatial symbol is associated with 2 number character. The number characters have a range from -1919 through 1919. These number characters are used for the X,Y position of the top left of the symbol when placed on a 2 dimensional grid.

Data Stream

ABNF Definition

• 7 bit ASCII
  • ASCII = %x00-7F;
• ISWA
  • ISWA = %x100-F0FF;
  • WRITING_SYM = %x100-EBBF;
  • CENTERING_SYM = %xB980-E61F;
  • PUNCTUATION_SYM = %xEBC0-ED9F;
  • SORTING_SYM = %xEDA0-F09F;
• Control
  • CONTROL_CHARS = %x80-FF;
  • SIGN_MARKER = %x80;
  • SEQUENCE_MARKER = %x81;
  • LEFT_LANE = %x82;
  • RIGHT_LANE = %x83;
• Number
  • NUM_CHAR = %xF100-FFFE;
• Constructed
  • COORD = NUM_CHAR NUM_CHAR;
  • SPATIAL_CHAR = WRITING_SYM COORD;
  • CLUSTER = *(SPATIAL_CHAR)
  • SIGN = (LEFT_LANE / SIGN_MARKER / RIGHT_LANE) CLUSTER;
  • SEQUENCE = SEQUENCE_MARKER *(WRITING_SYM / SORTING_SYM);
  • SIGN_TEXT = *(SIGN [SEQUENCE] / PUNCTUATION_SYM);

Token Stream

Token definition

• B = SIGN_MARKER;
• L = LEFT_LANE;
• R = RIGHT_LANE;
• w = WRITING_SYM except for CENTERING_SYM;
• c = CENTERING_SYM;
• n = NUM_CHAR
• Q = SEQUENCE_MARKER
• s = SORTING_SYM;
• P = PUNCTUATION_SYM;

Reqular expressions

• cluster = /[LBR]([wc]nn)*/i
• sequence = /Q[wcs]*/i
• punctuation = /P/i
• signtext = /^([LBR]([wc]nn)*(Q[wcs]*)?|P)+$/i

Unicode Integration

The plane 4 solution makes it possible to convert sign language data encoded with Binary SignWriting into a Unicode string. An entire 16-bit Unicode plane is used for character mapping. The plane 4 solution was created after the sign language data model. All consideration was given to fulfilling the requirements of sign language data: using the ISWA 2008 with spatial information. The plane 4 solution is as simple as possible without consideration of Unicode's definitions and restrictions. There may be more complex solutions that fit Unicode's paradigm better; however, any solution must be able to represent the entirety of Binary SignWriting.

Just because we can represent sign language data with UTF-8 doesn't mean that we use Unicode internally. The binary data must fulfill the model and have an equivalent Unicode representation. Binary SignWriting is a robust encoding model that satisfied the requirements and is Unicode compatible.

PHP example

 function char2unicode($char){
   $code = hexdec($char);
   $a = $code%64;
   $b = floor($code/64);
   $c = floor($b/64);
   $b -= $c*64;
  
   $utf8[]  = "f1";
   $utf8[]  = dechex($c + 128);
   $utf8[]  = dechex($b + 128);
   $utf8[]  = dechex($a + 128);
   return "%" . implode("%",$utf8);
 }

JavaScript example

 function char2unicode(char){
   var code = hex2dec(char);
   var a = code%64;
   var b = Math.floor(code/64);
   var c = Math.floor(b/64);
   b -= c*64;
   a += 128;
   b += 128;
   c += 128;
   return '%f1'+'%'+c.toString(16)+'%'+b.toString(16)+'%'+a.toString(16);
 }

Hello World

• data stream = 00801ce0f8d4f8ec8746f8eaf8fe008032eaf89ef91432e1f897f8fb5ec0f8b1f901b3b4f8a9f8e5ec20
• token stream = BwnnwnnBwnnwnnwnnwnnP
• unicode string = 񀂀񁳠񏣔񏣬񈝆񏣪񏣾񀂀񃋪񏢞񏤔񃋡񏢗񏣻񅻀񏢱񏤁񋎴񏢩񏣥񎰠

4. Glyphs

PHP

Basic Example	<img src="glyph.php?code=256">
Colorize	<img src="glyph.php?code=256&colorize=1">
Line Color	<img src="glyph.php?code=256&line=00ff00">
Fill Color	<img src="glyph.php?code=256&fill=ff0000">
Size	<img src="glyph.php?code=256&size=0.7">
Multiple	<img src="glyph.php?code=256&size=0.7&line=00ff00&fill=ff0000">

JavaScript

5. Glyphogram

Glyphogram Data Stream

Consider the following Binary SignWriting: 00801ce0f8d4f8ec8746f8eaf8fe

Char	Token	Value
0080	B	SIGN_MARKER
1ce0	w
f8d4	n	X = 85
f8ec	n	Y = 109
8746	w
f8ea	n	X = 107
f8fe	n	X = 127

PHP

Basic Example	<img src="glyphogram.php?bsw=0080...">
Colorize	<img src="glyphogram.php?bsw=0080...&colorize=1">
Size	<img src="glyphogram.php?bsw=0080...&size=0.7">
Line Color	<img src="glyphogram.php?bsw=0080...&line=ff0000">
Fill Color	<img src="glyphogram.php?bsw=0080...&fill=ff0000">
Multiple	<img src="glyphogram.php?bsw=0080...&size=0.7&colorize=1">

6. Column

Consider the following BSW:
Data Stream: 00801ce0f8d4f8ec8746f8eaf8fe008032eaf89ef91432e1f897f8fb5ec0f8b1f901b3b4f8a9f8e5ec20
Token Stream: BwnnwnnBwnnwnnwnnwnnP

PHP

Basic Example	<img src="column.php?bsw=0080...">
Colorize	<img src="column.php?bsw=0080...&colorize=1">
Size	<img src="column.php?bsw=0080...&size=0.7">
Line Color	<img src="column.php?bsw=0080...&line=ff0000">
Fill Color	<img src="column.php?bsw=0080...&fill=ff0000">
Multiple	<img src="column.php?bsw=0080...&size=0.7&colorize=1">

7. SymbolPalette

Organization

Function

Any symbol can be dragged from the SymbolPalette. The symbols can be dropped in a SignBox or a SymbolList, described below in the SignMaker section.

8. SignMaker

SignBox

The SignBox is the large empty square. Symbols from the SymbolPalette can be dropped in the SignBox. Selected symbols appear in blue. It is possible to select multiple symbols by clicking and dragging accross the SignBox, which will select all symbols between the start and end of the drag. Holding the shift key while clicking will also allow multiple selection of symbols.

Special Commands

The special commands are below the SignBox.

• SymbolGroup List - Returns the SymbolPalette to the top layer of SymbolGroups.
• Previous - Returns the SymbolPalette to the previous layer of BaseSymbols or SymbolGroups.
• Save - Forwards the build and sequence strings to save page. This is controlled by a javascript variable "accept" defined in "signmaker.php" on line 60.
• Copy Symbol - Copies the selected symbols
• Delete Symbol - Deletes the selected symbols
• Clear All - Deleted all symbols in the SignBox
• Variation - Switches symbols between the defined variations. Now all symbols have variations. See variation column in the code pages.
• Mirror - Flips most symbols on the vertical axis. See function "fnSBMirror" in "signmaker.js" defined on line 508.
• Fill Symbol - Cycles through the valid fills for the symbols. See the valid fills column in the code pages.
• Place Over - The selected symbols will be placed on top of the other symbols. This is useful for symbols that have fills, such as hand shapes and arrows.
• Select Previous & Next - Cycles the selected symbol from the first symbol added to the last, or visa versa.
• Rotate 1 & 2 - Rotates the symbols clockwise or counter clockwise according to the valid rotations. See valid rotations column in the code pages.
• Arrows and grid - The arrows will move the selected symbols 1 pixel at a time. The grid button in the middle will display the SignBox grid to help with symbol placement.

SignSpelling Sequence

9. Project Files

Data Files

SymbolGroup Data

• code - character code
• view - character code to use when viewing the SymbolGroup
• sid_c - symbol id category number
• sid_g - symbol id group number
• num - SymbolGroup number
• bases - number of BaseSymbols in the SymbolGroup
• color - standard color
• flags - purpose of SymbolGroup (writing, centering, punctuation, or sorting), any of [wcps]
• name - SymbolGroup name

BaseSymbol Data

• code - character code
• view - character code to use when viewing the BaseSymbol
• sid_b - symbol id base number
• sid_v - symbol id variation number
• num - BaseSymbol number
• vars - binary value for variations
• fills - binary value for valid fills (see ISWA.php validcode function)
• rots - binary value for valid rotations (see ISWA.php validcode function)
• name - BaseSymbol name

Font Files

License Files

In the iswa subdirectory, there are 2 files regarding the Open Font License: OFL.txt and OFL-FAQ.txt.

Release Candidate 1