NAME
djvudigital - creates DjVu files from PS or PDF files.
SYNOPSIS
djvudigital [options] inputfile [outputfile]
DESCRIPTION
This program creates a DjVu file from the PostScript (.ps), GZipped
PostScript (.ps.gz), Encapsulated PostScript (.eps), or Portable
Document Format (.pdf) file inputfile.
The output file name is either given by argument outputfile or
generated by replacing the input file name suffixes by the DjVu suffix
(.djvu).
PREREQUISITES
This program depends on a specific GhostScript driver. If your
GhostScript program does not provide this driver, please check
http://djvu.sourceforge.net/gsdjvu.html.
OPTIONS
--verbose, -v
Displays more informational messages while converting the file.
--quiet, -q
Do not display informational messages while converting the file.
--dpi=resolution
Specify the desired resolution to resolution dots per inch. The
default is 600 dpi.
--psrotate=angle
Rotate the PostScript file by angle degrees clockwise. Only the
values 0, 90, 180, and 270 are supported. This option only
applies to PostScript files. PDF files are always converted
according to their native orientation.
--epsf=disposition
Specify how to handle Encapsulated PostScript files. Argument
disposition can take the values crop, fit, and ignore. The
default disposition crop creates a DjVu file whose size matches
the bounding box of the Encapsulated PostScript file. Value fit
rescales the graphics to the default page size. Value ignore
disables all Encapsulated PostScript specific code. This option
requires Ghostscript 7.07 or better.
--exact-color
Enables a more accurate rendering of the colors. This option
requires GhostScript 6.52 or better.
--threshold=thres
Specify a threshold for the foreground/background separation
code. Acceptable values of thres range from 0 to 100. Larger
values place more information into the foreground layer. The
default threshold value is 80.
--bg-subsample=sub
Specify the background subsampling ratio. Argument sub must be
an integer between 1 and 6. The default value is 3.
--bg-slices=n+...+n
Specify the encoding quality of the background layer. The
syntax for the argument is similar to that described for the
-slice option of command c44. The default is 72+11+10+10.
--fg-colors=ncolors
Specify the maximum number of distinct colors in the foreground
layer. Argument ncolors can take integer values between 1 and
4000. The default value is 256.
--fg-image-colors=ncolors
Specify the maximum number of distinct colors in an image for
considering encoding it into the foreground layer. Argument
ncolors can take integer values between 1 and 4000. The default
value is 256.
--words
Extract the text from the PostScript code and incorporates this
information into the DjVu file. This option records the
location of every word.
--lines
Extract the text from the PostScript code and incorporates this
information into the DjVu file. This option saves a few bytes
by only recording the location of each line.
--gsarg=arg1[,arg2,...,argN]
Insert extra arguments on the GhostScript command line.
--cseparg=arg1[,arg2,...,argN]
Insert extra arguments on the command line of program csepdjvu
or msepdjvu.
--sepfile
Produces a separated data file instead of a DjVu file. Program
csepdjvu can then convert the separated data file into a DjVu
file.
--check
Display the names of the two auxiliary programs found by
djvudigital, namely a suitable ghostscript interpreter and a
suitable backend encoder. See the next two section for details.
--dryrun
Simply display the ghostscript command line generated by
djvudigital without running it. No output file is produced
--help Display the manual page for djvudigital.
GHOSTSCRIPT ISSUES
Program djvudigital internally relies on a specific Ghostscript driver
named djvusep. This driver analyzes the logical structure of the
sequence of PostScript rendering commands and decides to execute each
command into either the foreground or the background layer. The
GhostScript driver produces a separated data file that is then
compressed using the DjVuLibre program csepdjvu.
Before processing the input file, program djvudigital searches a
Ghostscript executable providing the djvusep driver. The search starts
with the file specified by the environment variable GSDJVU and
continues with command line executables named gs and gsdjvu.
The DjVuLibre source code contains instruction to compile such a
GhostScript executable. More information can be obtained from
http://djvu.sourceforge.net/gsdjvu.html.
CSEPDJVU ISSUES
The output of the djvusep GhostScript driver must be processed by the
DjVuLibre program csepdjvu. This program can also be replaced by the
the proprietary Lizardtech program msepdjvu. Before processing the
input file, program djvudigital searches such an executable. The
search starts with the file specified by the environment variable
CSEPDJVU and continues with command line executables named msepdjvu and
csepdjvu.
CREDITS
The first version of this converter was written by Leon Bottou
<leonb@users.sourceforge.net> in AT&T Labs. The DjVuLibre version is
derived from code graciously released by Lizardtech in January 2004.
BUGS
Program djvudigital can only process input files that GhostScript can
process properly.
SEE ALSO
djvu(1), csepdjvu(1), c44(1), gs(1), gzip(1)