Table Designator: ibo
A translation table is a module in DBT that provides the rules to convert (translate) a document from print-to-braille or from braille-to-print. Normally, it is selected by the DBT template that controls production of the current document. All documents have a template. In fact, for many languages there are multiple templates, with differences in translation rules or formatting, but each references at least one translation table. (For more on templates, see DBT Templates, the Basics.)
Regardless of your template, you can choose a different translation table to translate your current document using the Translation Table selection from the DBT Document Menu.
You can also select different translation tables to use for particular passages in your document. See the section below on Language Table Switching.
The Igbo tables support print-to-braille translation of Igbo-language literary text into contracted (grade 2) or uncontracted (grade 1) braille.
Translation from braille-to-print is supported for this language.
Table Designator: ibo identifies this translation table for Language Table Switching.
Braille Contractions: This language is usually produced in contracted braille, which means one should not expect a one-to-one correspondence between inkprint letters and braille cells. Instead, abbreviations (contractions) are used for many common words and letter sequences.
Capital Sign: Igbo uses dot 6 as the capital sign.
Emphasis: The Igbo translator converts all forms of emphasis in inkprint (bold, italics, and underlining) to a single braille emphasis marker, dots 46.
Mathematical Braille: This translator defaults to using the UEB braille mathematics translator by using the math style.
Script Systems Used: The Igbo translator handles Roman characters, and a wide variety of symbols and punctuation marks. (See the next section.)
Data Entry: Igbo Accent Marks
Igbo uses the Roman alphabet. However, the Igbo language employs accent marks (diacritical marks) to modify certain letters. The accent marks are of three types.
First, Igbo vowels may be marked as high, middle, or low in tone by adding an acute accent, macron, or grave accent respectively. The middle tone is not normally marked explicitly, but can be in some circumstances.
For the second type, the vowels i, o, and u may be marked with a dot under the base letter. This means that some vowels can have diacritical marks both above (for tone) and below. Also, as a matter of style, some documents use a plus sign below these vowels instead of the dot below.
For the third accent type, the letter n may be marked with a dot above. Also, as a stylistic matter, some documents use a caron above the n in place of a dot.
Data Entry Options: Very often in Unicode, pre-composed versions of these characters with diacritical marks are available and may be entered directly, for example, pre-composed "n with caron" (U+0148).
Alternatively, accent marks may be added to the base letter by entering a "combining" Unicode accent immediately after the base letter.
For the tones, the combining accent characters are U+0300 for combining grave accent (low tone), U+0301 for combining acute accent (high tone), and U+0304 for combining macron (middle tone).
For the second type, the combining marks are: U+0323 for combining dot below, or U+031F for combining plus below.
For the third type, the character U+E337 provides the combining dot above.
It is possible to enter a character using a combination of pre-composed and combining accents. For example, a pre-composed u with acute accent may be combined with a combining dot below. When more than one combining mark is needed, they may be entered in any order as long as all follow the basic letter that they are modifying.
Translation Modes (DBT Codes which Change the Mode of Translation)
A number of DBT codes affect the mode of the translation or create special translation effects on specific letters or symbols. Some translation modes are specific to particular translator tables.
[g1] switches to grade 1 as the "prevailing grade", but does not insert a grade 1 indicator.
[g2] resumes grade 2 as the prevailing grade, but does not insert a grade 2 indicator. (Grade 2 is the normal prevailing grade.)
For more about DBT codes that affect the mode of translation, search on the two words, "translation code", in the topic, DBT Codes Quick Reference.
Language Table Switching
DBT has translation tables for over 200 world languages. Modern versions of DBT allow using multiple language translation tables within a single document.
Suppose that you are working on a document using this base translation table, but it has passages in a foreign language, or that need a technical braille code. At the beginning of each such passage, insert the DBT code lnb, followed by ~ (tilde) and the table designator for the desired language table. (The table designator for each language table is listed in the Key Characteristics.) Note that using the lnb code you can change from the base table to virtually any other translation table and back again.
For some language tables, the table designator is short, like ise for Icelandic. Thus, to switch to Icelandic braille translation, insert [lnb~ise]. The table designators are more elaborate for mathematics code tables and for languages that have multiple translation tables. As an example, the designator for Unified French Braille is fra-xuf. To start a passage in the French Unified Braille code, insert [lnb~fra-xuf]. At the end of a foreign language passage, use the plain [lnb] code to switch back to the original, base, language translation table.
Some translation tables, and hence their table designators, are for braille codes but not for natural languages. Some examples are the International Phonetic Alphabet (designator: qip) and Nemeth Code (designator: qmt-xnem72m) for mathematics. Using lnb with those table designators allows you to switch to the IPA braille code or the Nemeth braille math code.
While a plain [lnb] code returns translation to the base language, it does not restore any other translation properties that might have been in effect before the switch. For example, if you had been using a [g1L] code (for "grade 1 lock") to prevent contractions, you need to repeat that code after the [lnb] code to restore that effect. Fortunately, you can build lnb codes into DBT styles, to customize what modes to enter and exit at the switch in and out of a translation table.
Note that DBT templates whose names contain the word "basic" all have a number of styles defined for switching between different translation tables. (For the list, see Basic Templates.)
References, History, and Credits
Duxbury Systems originally developed the Igbo translator beginning in May 2005. The Igbo tables were based upon information provided to Duxbury Systems by Mrs. Jean Obi.
Updates and Errors
If you have information about changes in the braille rules for your language, please email Duxbury so that we may update our translation tables. Likewise, if you find errors in your translated document, in either the print-to-braille or braille-to-print direction, please contact us. To describe your problem, it is best to send both the *.dxp and *.dxb files along with a full explanation, because the correct braille is often a matter of very specific circumstances. Contact Duxbury at: firstname.lastname@example.org.