NAME
djvutoxml, djvuxmlparser - DjVuLibre XML Tools.
SYNOPSIS
djvutoxml [options] inputdjvufile [outputxmlfile]
djvuxmlparser [inputxmlfile]
DESCRIPTION
The DjVuLibre XML Tools provide for editing the metadata, hyperlinks
and hidden text associated with DjVu files. Unlike djvused(1) the
DjVuLibre XML Tools rely on the XML technology and can take advantage
of XML editors and verifiers.
DJVUTOXML
Program djvutoxml creates a XML file outputxmlfile containing a
reference to the original DjVu document inputdjvufile as well as tags
describing the metadata, hyperlinks, and hidden text associated with
the DjVu file.
The following options are supported:
--page pagenum
Select a page in a multi-page document. Without this option,
djvutoxml outputs the XML corresponding to all pages of the
document.
--with-text
Specifies the HIDDENTEXT element for each page should be
included in the output. If specified without the --with-anno
flag then the --without-anno is implied. If none of the --with-
text, --without-text, --with-anno, or --without-anno, flags are
specified, then the --with-text and --with-anno flags are
implied.
--without-text
Specifies not to output the HIDDENTEXT element for each page.
If specified without the --without-anno flag then the --with-
anno flag is implied.
--with-anno
Specifies the area MAP element for each page should be included
in the output. If specified without the --with-text flag then
the --without-text flag is implied.
--without-anno
Specifies the area MAP element for each page should not be
included in the output. If specified without the --without-text
flag then the --with-text flag is implied.
DJVUXMLPARSER
Files produced by djvutoxml can then be modified using either a text
editor or a XML editor. Program djvuxmlparser parses the XML file
inputxmlfile and modifies the metadata of the DjVu files referenced by
the OBJECT elements.
DJVUXML DOCUMENT TYPE DEFINITION
The document type definition file (DTD)
/usr/share/djvu/pubtext/DjVuXML-s.dtd
defines the input and output of the DjVu XML tools.
The DjVuXML-s DTD is a simplification of the HTML DTD:
http://www.w3c.org/TR/1998/REC-html40-19980424/sgml/dtd.html
with a few new attributes added specific to DjVu. Each of the
specified pages of a DjVu document are represented as OBJECT elements
within the BODY element of the XML file. Each OBJECT element may
contain multiple PARAM elements to specify attributes like page name,
resolution, and gamma factor. Each OBJECT element may also contain one
HIDDENTTEXT element to specify the hidden text (usually generated with
an OCR engine) within the DjVu page. In addition each OBJECT element
may reference a single area MAP element which contains multiple AREA
elements to represent all the hyperlink and highlight areas within the
DjVu document.
PARAM Elements
Legal PARAM elements of a DjVu OBJECT include but are not limited to
PAGE for specifying the page-name, GAMMA for specifying the gamma
correction factor (normally 2.2), and DPI for specifying the page
resolution.
HIDDENTEXT Elements
The HIDDENTEXT elements consists of nested elements of PAGECOLUMNS,
REGION, PARAGRAPH, LINE, and WORD. The most deeply nested element
specified, should specify the bounding coordinates of the element in
top-down orientation. The body of the most deeply nested element
should contain the text. Most DjVu documents use either LINE or WORD
as the lowest level element, but any element is legal as the lowest
level element. A white space is always added between WORD elements and
a line feed is always added between LINE elements. Since languages
such as Japanese do not use spaces between words, it is quite common
for Asian OCR engines to use WORD as characters instead.
MAP Elements
The body of the MAP elements consist of AREA elements. In addition to
the attributes listed in
http://www.w3.org/TR/1998/REC-html40-19980424/struct/objects.html#edef-AREA,
the attributes bordertype, bordercolor, border, and highlight have been
added to specify border type, border color, border width, and highlight
colors respectively. Legal values for each of these attributes are
listed in the DjVuXML-s DTD. In addition, the shape oval has been
added to the legal list of shapes. An oval uses a rectangular bounding
box.
BUGS
Perhaps it would have been better to use CC2 style sheets with standard
HTML elements instead of defining the HIDDENTEXT element.
CREDITS
The DjVu XML tools and DTD were written by Bill C. Riemers
<docbill@sourceforge.net> and Fred Crary.
SEE ALSO
djvu(1), djvused(1), and utf8(7).