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  300
              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.

       --poppler=keywords
              This option causes djvudigital to extract additional  information  from  PDF  files
              using  the  tool  pdftotext  that comes bundled with the Poppler library.  Selected
              information is then added to the djvu file as a postprocessing step. This option is
              ignored  when  the  input  file  is  not  a PDF file.  Argument keywords is a comma
              separated list of keywords.  When this list contains  keyword  meta,  the  metadata
              extracted  by  pdftotext  is  inserted into the djvu file.  When this list contains
              keyword text, the textual information extracted by pdftotext is inserted  into  the
              djvu file, possibly replacing the information gathered using the options --words or
              --lines.  This is useful for instance when a scanned PDF  file  contains  a  hidden
              text  layer  that  is not recognized by Ghostscript and therefore not passed to the
              djvudigital backend.

       --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.

OTHER PROGRAMS

       The  option  --poppler=keywords  relies  on the tool pdftotext that comes with the Poppler
       library and the tool djvused that comes with djvulibre.  Only recent versions of pdftotext
       that  accept  the option -bbox are supported.  Both tools are searched by first trying the
       files specified by the environment  variables  PDFTOTEXT  and  DJVUSED,  and  then  trying
       executables named pdftotext or djvused found along the shell executable path.

CREDITS

       The    first    version    of    this    converter    was    written    by   Léon   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)