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DDJVU(1)			 DjVuLibre-3.5			      DDJVU(1)

       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
		 (PPM) 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 using
		 lossless compression.	Enabling lossy JPEG  compression  (see
		 option	 -quality  below)  often  produces much	smaller	files.
		 Commands tiffcp(1) and	tiffsplit(1) are useful	for manipulat-
		 ing 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 lossless compression.  En-
		 abling	lossy JPEG compression (see option -quality below) of-
		 ten 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 converter.

	      When  option -format is not specified, the extension of argument
	      outputfile has no	influence on the default output	 format.   In-
	      stead  the  program behavior is modified to ensure backward com-
	      patibility with previous versions	of ddjvu.  We recommend	to al-
	      ways 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  concate-
	      nated  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.

	      When this	option is specified, program ddjvu generates one sepa-
	      rate  file  per  page named by replacing the %d specification in
	      outputfilename by	the page number	in a  manner  simular  to  the
	      printf(3)	function.

	      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  depend-
		 ing  on  the  subsampling factor.  Otherwise a	color image is

	      *	 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  spe-
		 cific	layers	of  a DjVu image.  These modes can fail	if the
		 DjVu image does not contain the selected layer.

       -skip  Instead of aborting when encountering a corrupted	page, this op-
	      tion causes ddjvu	to simply skip the corrupted page and continue
	      with the next.  This is useful for  processing  certain  damaged

       The  following options control the resolution of	the output image.  The
       default resolution is the native	resolution of the DjVu	file,  equiva-
       lent 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.  Op-
	      tion -1, for instance, produces an output	image whose resolution
	      is equal to the resolution of the	input DjVu image file.

	      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 com-
	      puter screen.  The magnification factor mag can also  be	inter-
	      preted  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 combina-
	      tion 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 posi-
	      tion (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	speci-

	      Enables lossy JPEG compression for TIFF and PDF files.  This op-
	      tion  only  affects images that cannot be	encoded	using the pre-
	      ferred TIFF/G4 compression.  Argument factor is  a  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.

	      Completely disables compression in TIFF and PDF files.  Although
	      the resulting files are often huge, this is sometimes useful for
	      maximal compatibility with hastily written software.

	      Enables  DEFLATE compression for TIFF files.  Images that	cannot
	      be encoded using the preferred TIFF/G4 compression will  be  en-
	      coded with DEFLATE compression if	available.  Otherwise the more
	      portable PACKBITS	compression is used.  Specifying  this	option
	      is  not  necessary for PDF files because this is the default be-

       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=1-10	 -eachpage  -size=100x100  myfile.djvu

       produces	 100x100  thumbnails  for the first ten	page of	a document and
       outputs them as PPM files named thumb001.ppm to thumb010.ppm.

       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),	tiffs-
       plit(1),	tiffcp(1), printf(3)

DjVuLibre-3.5			  10/19/2002			      DDJVU(1)


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