1DJVUDIGITAL(1)                   DjVuLibre-3.5                  DJVUDIGITAL(1)
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NAME

6       djvudigital - creates DjVu files from PS or PDF files.
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SYNOPSIS

10       djvudigital  [options] inputfile [outputfile]
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DESCRIPTION

14       This  program  creates  a  DjVu file from the PostScript (.ps), GZipped
15       PostScript (.ps.gz), Encapsulated PostScript (.eps), or Portable  Docu‐
16       ment Format (.pdf) file inputfile.
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18       The  output  file name is either given by argument outputfile or gener‐
19       ated by replacing the input file  name  suffixes  by  the  DjVu  suffix
20       (.djvu).
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PREREQUISITES

24       This  program depends on a specific GhostScript driver.  If your Ghost‐
25       Script  program  does   not   provide   this   driver,   please   check
26       http://djvu.sourceforge.net/gsdjvu.html.
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OPTIONS

30       --verbose, -v
31              Displays more informational messages while converting the file.
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33       --quiet, -q
34              Do not display informational messages while converting the file.
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36       --dpi=resolution
37              Specify the desired resolution to resolution dots per inch.  The
38              default is 300 dpi.
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40       --psrotate=angle
41              Rotate the PostScript file by angle degrees clockwise.  Only the
42              values  0, 90, 180, and 270 are supported.  This option only ap‐
43              plies to PostScript files.  PDF files are always  converted  ac‐
44              cording to their native orientation.
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46       --epsf=disposition
47              Specify  how  to handle Encapsulated PostScript files.  Argument
48              disposition can take the values crop, fit, and ignore.  The  de‐
49              fault  disposition  crop  creates a DjVu file whose size matches
50              the bounding box of the Encapsulated PostScript file. Value  fit
51              rescales  the  graphics  to the default page size.  Value ignore
52              disables all Encapsulated PostScript specific code.  This option
53              requires Ghostscript 7.07 or better.
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55       --exact-color
56              Enables  a  more  accurate rendering of the colors.  This option
57              requires GhostScript 6.52 or better.
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59       --threshold=thres
60              Specify a threshold  for  the  foreground/background  separation
61              code.   Acceptable  values  of thres range from 0 to 100. Larger
62              values place more information into the  foreground  layer.   The
63              default threshold value is 80.
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65       --bg-subsample=sub
66              Specify  the background subsampling ratio.  Argument sub must be
67              an integer between 1 and 6.  The default value is 3.
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69       --bg-slices=n+...+n
70              Specify the encoding quality of the background layer.  The  syn‐
71              tax for the argument is similar to that described for the -slice
72              option of command c44.  The default is 72+11+10+10.
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74       --fg-colors=ncolors
75              Specify the maximum number of distinct colors in the  foreground
76              layer.   Argument  ncolors can take integer values between 1 and
77              4000.  The default value is 256.
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79       --fg-image-colors=ncolors
80              Specify the maximum number of distinct colors in  an  image  for
81              considering  encoding  it  into  the foreground layer.  Argument
82              ncolors can take integer values between 1 and 4000.  The default
83              value is 256.
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85       --words
86              Extract  the text from the PostScript code and incorporates this
87              information into the DjVu file.  This option records  the  loca‐
88              tion of every word.
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90       --lines
91              Extract  the text from the PostScript code and incorporates this
92              information into the DjVu file.  This option saves a  few  bytes
93              by only recording the location of each line.
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95       --gsarg=arg1[,arg2,...,argN]
96              Insert extra arguments on the GhostScript command line.
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98       --cseparg=arg1[,arg2,...,argN]
99              Insert  extra  arguments on the command line of program csepdjvu
100              or msepdjvu.
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102       --poppler=keywords
103              This option causes djvudigital to extract additional information
104              from  PDF files using the tool pdftotext that comes bundled with
105              the Poppler library.  Selected information is then added to  the
106              djvu  file as a postprocessing step. This option is ignored when
107              the input file is not a PDF file.  Argument keywords is a  comma
108              separated  list  of  keywords.   When this list contains keyword
109              meta, the metadata extracted by pdftotext is inserted  into  the
110              djvu  file.   When  this list contains keyword text, the textual
111              information extracted by pdftotext is  inserted  into  the  djvu
112              file,  possibly replacing the information gathered using the op‐
113              tions --words or --lines.  This is useful for  instance  when  a
114              scanned PDF file contains a hidden text layer that is not recog‐
115              nized by Ghostscript and therefore not passed to the djvudigital
116              backend.
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118       --sepfile
119              Produces  a  separated data file instead of a DjVu file. Program
120              csepdjvu can then convert the separated data file  into  a  DjVu
121              file.
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123       --check
124              Display  the  names  of  the  two  auxiliary  programs  found by
125              djvudigital, namely a suitable  ghostscript  interpreter  and  a
126              suitable backend encoder.  See the next two section for details.
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128       --dryrun
129              Simply   display  the  ghostscript  command  line  generated  by
130              djvudigital without running it.  No output file is produced
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132       --help Display the manual page for djvudigital.
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GHOSTSCRIPT ISSUES

135       Program djvudigital internally relies on a specific Ghostscript  driver
136       named  djvusep.   This driver analyzes the logical structure of the se‐
137       quence of PostScript rendering commands and  decides  to  execute  each
138       command into either the foreground or the background layer.  The Ghost‐
139       Script driver produces a separated data file that  is  then  compressed
140       using the DjVuLibre program csepdjvu.
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142       Before processing the input file, program djvudigital searches a Ghost‐
143       script executable providing the djvusep driver. The search starts  with
144       the  file  specified  by  the environment variable GSDJVU and continues
145       with command line executables named gs and gsdjvu.
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147       The DjVuLibre source code contains instruction to compile such a Ghost‐
148       Script   executable.    More   information   can   be   obtained   from
149       http://djvu.sourceforge.net/gsdjvu.html.
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CSEPDJVU ISSUES

153       The output of the djvusep GhostScript driver must be processed  by  the
154       DjVuLibre  program  csepdjvu.  This program can also be replaced by the
155       the proprietary Lizardtech program msepdjvu.  Before processing the in‐
156       put  file, program djvudigital searches such an executable.  The search
157       starts with the file specified by the environment variable CSEPDJVU and
158       continues with command line executables named msepdjvu and csepdjvu.
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OTHER PROGRAMS

162       The  option  --poppler=keywords relies on the tool pdftotext that comes
163       with the Poppler library and the tool djvused that comes  with  djvuli‐
164       bre.   Only  recent  versions of pdftotext that accept the option -bbox
165       are supported.  Both tools are searched by first trying the files spec‐
166       ified by the environment variables PDFTOTEXT and DJVUSED, and then try‐
167       ing executables named pdftotext or djvused found along the  shell  exe‐
168       cutable path.
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CREDITS

172       The  first  version  of  this  converter  was  written  by  Léon Bottou
173       <leonb@users.sourceforge.net> in AT&T Labs.  The DjVuLibre  version  is
174       derived from code graciously released by Lizardtech in January 2004.
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BUGS

178       Program  djvudigital  can only process input files that GhostScript can
179       process properly.
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SEE ALSO

183       djvu(1), csepdjvu(1), c44(1), gs(1), gzip(1)
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187DjVuLibre-3.5                      1/31/2004                    DJVUDIGITAL(1)
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