djvu2hocr1
Djvu to hocr converter
Usage
djvu2hocr [option ...]
djvu-file
djvu2hocr {--version | --help | -h}
Overview
djvu2hocr converts hidden text from a DjVu file to the hOCR[1] format.
Options
Input selection options
-
-p, --pages=page-range -
Specifies pages to covert. page-range is a comma-separated list of sub-ranges. Each sub-range is either a single page (e.g. 17) or a contiguous range of pages (e.g. 37-42). Pages are numbered from 1.
The default is to convert all pages.
Text segmentation options
-
--word-segmentation=simple -
Use the same word segmentation as found in the DjVu file.
This is the default.
-
--word-segmentation=uax29 -
Use the Unicode Text Segmentation[2] algorithm to break lines into words, possibly fixing word segmentation found in the DjVu file.
HTML output options
-
--title=title -
Specifies the document title.
The default is “DjVu hidden text layer”.
-
--css=style -
Add the specified CSS style to the document.
For example, --css='.ocrx_line { display: block; }' can be used to visually preserve line breaks.
Other options
-
--version -
Output version information and exit.
-
-h, --help -
Display help and exit.
Portability
djvu2hocr uses a custom extension to hOCR to retain characters which cannot be directly represented in an HTML/XML document. For example, control character BEL (^G, U+0007), is converted into the following HTML chunk: <span class="djvu_char" title="#x07"> </span>
Notes
- 1.
-
hOCR
https://docs.google.com/View?docid=dfxcv4vc_67g844kf
- 2.
-
Unicode Text Segmentation
https://unicode.org/reports/tr29/
Releases
5 releases since Debian 6.0 (Squeeze); the text changed 4 times.
--css since Debian 8 (Jessie);
--pages since Debian 8 (Jessie);
--title since Debian 8 (Jessie);
-p since Debian 8 (Jessie).