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       ddjvu - Command line DjVu decoder.


       ddjvu -format=fmt [options] [djvufile] [outputfile]


       Decode the DjVu file djvufile, produces the image file outputfile.

       The DjVu data is read from the standard input when argument djvufile is
       not specified or when it is equal to a  single  dash.   Similarly,  the
       output  data is written to the standard output when argument outputfile
       is not specified or equal to a single dash.   However  a  valid  output
       file name is always required when producing a TIFF or PDF file.


              Specify  the  output  file formats.  The recognized file formats
              are pbm, pgm, ppm, pnm, rle, tiff, and pdf.

              *  Formats pbm, pgm, and ppm  respectively  produce  a  Portable
                 Bitmap  (PBM),  Portable  Graymap  (PGM),  or Portable Pixmap
                 (PGM) file.  Format pnm produces a PBM, PGM,  or  PPM  output
                 file according to the color content of the output image.

              *  Format rle produces a compact run length encoded bitonal file
                 that  is  understood  by  the  DjVuLibre  commands  cjb2  and

              *  Format  tiff produces a Tagged Image Format (TIFF) file.  The
                 resulting file uses the best available  lossless  compression
                 model.   Enabling lossy JPEG compression (see option -quality
                 below) often produces much smaller files.  Commands tiffcp(1)
                 and  tiffsplit(1)  are  useful for manipulating the resulting
                 TIFF files.

              *  Format pdf produces a Portable Document  Format  (PDF)  file.
                 Each page in the resulting file is represented by an image at
                 the specified resolution, using the best  available  lossless
                 compression  model.   Enabling  lossy  JPEG  compression (see
                 option -quality below) often produces much smaller files.  An
                 alternate  way  to  produce  PDF file consists in first using
                 djvups(1) and convert the resulting PostScript file  to  PDF.
                 Which  method gives better results depends on the contents of
                 the DJVU file and on  the  capabilities  of  the  PS  to  PDF

              When  option -format is not specified, the extension of argument
              outputfile has  no  influence  on  the  default  output  format.
              Instead  the  program  behavior  is  modified to ensure backward
              compatibility with previous versions of ddjvu.  We recommend  to
              always specify the output format using this option.

              Specify  which pages should be decoded.  When this option is not
              specified,  all  pages  of  the  documents   are   decoded   and
              concatenated  into  the  output  file.   The  page specification
              pagespec contains one or more comma-separated  page  ranges.   A
              page  range  is  either  a  page  number,  or  two  page numbers
              separated by a dash.  For instance, specification  1-10  outputs
              pages 1 to 10, and specification 1,3,99999-4 outputs pages 1 and
              3, followed by all the document pages in  reverse  order  up  to
              page 4.

              Selects  which  layers  of  the  DjVu  image should be rendered.
              Valid rendering modes are color, black,  mask,  foreground,  and

              *  Rendering mode color is the default mode.  When the DjVu file
                 is  bitonal,  bitonal  or  gray-level  output   is   produced
                 depending on the subsampling factor.  Otherwise a color image
                 is produced.

              *  Rendering mode black is useful to extract a meaningful  black
                 and  white  image.   bitonal or gray-level output is produced
                 depending on the subsampling factor.

              *  Rendering  modes  mask,  foreground,  and  background  select
                 specific layers of a DjVu image.  These modes can fail if the
                 DjVu image does not contain the selected layer.


       The following options control the resolution of the output image.   The
       default   resolution  is  the  native  resolution  of  the  DjVu  file,
       equivalent to selecting -1.

       -n     Specify an integer sub-sampling factor.  The dimensions  of  the
              full  output  image  will be n times smaller than the DjVu image
              size.  The legal values for argument  n  range  from  1  to  12.
              Option   -1,  for  instance,  produces  an  output  image  whose
              resolution is equal to the resolution of the  input  DjVu  image

              This is equivalent to option -n.

              Specify a magnification factor relative to the resolution stored
              in the DjVu image.  Specifying magnification of 100 produces  an
              image  suitable  for  displaying  on  a 100 dpi device such as a
              computer screen.  The  magnification  factor  mag  can  also  be
              interpreted  as  the resolution of the output image expressed in
              dot per inch.

              Specify the size of the full output image.  Rendering  the  full
              DjVu  image  would create an output image whose width and height
              would not exceed w and h.  To change the aspect ratio, you  must
              also use option -aspect=no.

              This  option  indicates whether the image aspect ratio should be
              preserved.  The defaults is to preserve the aspect ration.  This
              option  permits  changes  in  the  aspect  ratio  when  used  in
              combination with option -size.


              Display informational messages describing the structure  of  the
              DjVu image and the format of the output file.

              Specify  an image segment to render.  Program ddjvu conceptually
              renders the full page using the specified resolution,  and  then
              extracts  a  sub-image  of  width  w  and  height h, starting at
              position (x,y) relative to the bottom left corner of  the  page.
              Both  operations  of  course happen simultaneously.  Rendering a
              small sub-image is  much  faster  than  rendering  the  complete
              image.   The  output  file  will  always have size wxh when this
              option is specified.

              Enables lossy compression in TIFF and PDF files.   Without  this
              option, TIFF or PDF output files always use lossless compression
              or  no  compression.    Argument   factor   specifies   a   JPEG
              quantization factor ranging from 25 to 150. See command cjpeg(1)
              for more information on JPEG quantization factors.  Value 80  is
              a good starting point.


       Various  options  have been maintained to ensure backward compatibility
       with previous versions of ddjvu.  When option -format is not specified,
       the program only decodes the first page of the document and the default
       resolution becomes -scale=100.  Options -size,  -scale,  -segment,  and
       -page  accept  an  argument separated by a space.  Options -foreground,
       -background, and  -black  are  shorthands  for  the  -mode=mod  option.
       Please do not rely on these features.



          ddjvu -format=tiff myfile.djvu myfile.tif

       decodes all pages and produces a multipage TIFF file.


          ddjvu -format=ppm -page=1 -size=100x100 myfile.djvu -

       produces a thumbnail for the first page of a document and outputs it as
       a PPM file on the standard output.


       The  new  version  of  this  program  was  written   by   Leon   Bottou

       This  program  includes  code derived from program tiff2pdf, written by
       Ross Finlayson and released under a BSD license.


       djvu(1),  djview(1),  pnm(5),   pbm(5),   pgm(5),   ppm(5),   cjpeg(1),
       tiffsplit(1), tiffcp(1)