Liblouis User's and Programmer's Manual

5.5 lou_translate ¶

This program translates whatever is on the standard input unit and prints it on the standard output unit. It is intended for large-scale testing of the accuracy of translation and back-translation. The command line for lou_translate is:

lou_translate [OPTION] TABLE

where ‘TABLE’ is either:

QUERY

a table query

FILE[,FILE,...]

a comma-separated list of table files

Aside from the standard options (see common options) this program also accepts the following options:

--forward

-f

Do a forward translation.

--backward

-b

Do a backward translation.

--display-table FILE

-d FILE

Use the given display table for the translation. This is useful when you are specifying the table as a query. This option takes precedence over any display table specified as part of the table files.

If no options are given forward translation is assumed.

Use the following command to do a forward translation of English text to grade 2 contracted braille according to the U.S. braille standard.

lou_translate --display-table unicode.dis language:en grade:2 region:en-US < input.txt

Use the following command to do a forward translation with translation table en-us-g2.ctb.

lou_translate --forward en-us-g2.ctb < input.txt

When you specify the table as a query, the braille encoding is always Unicode dot patterns, unless you specify a display table with the display-table option.

When you specify the table as a file list, the encoding of the resulting braille depends on the character definitions in the given table. It is recommended to use a display table, as in the following example, if you require a specific braille encoding.

The next example illustrates a forward translation with translation table en-us-g2.ctb and display table unicode.dis. The resulting braille is encoded as Unicode dot patterns (as defined in unicode.dis).

lou_translate --forward unicode.dis,en-us-g2.ctb < input.txt

Use a pipe if you would rather just pass some given text to the translator.

echo "The quick brown fox jumps over the lazy dog" | lou_translate -f unicode.dis,en-us-g2.ctb

The result will be written to standard output:

⠠⠮ ⠟⠅ ⠃⠗⠪⠝ ⠋⠕⠭ ⠚⠥⠍⠏⠎ ⠕⠧⠻ ⠮ ⠇⠁⠵⠽ ⠙⠕⠛

Backward translation can be done as follows:

echo ",! qk br{n fox jumps ov} ! lazy dog" | lou_translate --backward en-us-g2.ctb

which results in

The quick brown fox jumps over the lazy dog

You can also do a backward translation using Unicode dot patterns

echo "⠠⠮ ⠟⠅ ⠃⠗⠪⠝ ⠋⠕⠭" | lou_translate --backward unicode.dis,en-us-g2.ctb

resulting in

The quick brown fox