DIDJVU(1)							   didjvu manual							 DIDJVU(1)

NAME

       didjvu - DjVu encoder with foreground/background separation

SYNOPSIS

       didjvu separate [{-o | --output} output-mask] [option...] input-image

       didjvu separate --output-template name-template	[option...] input-image...

       didjvu encode [{-o | --output} output-djvu] [option...] input-image

       didjvu encode --output-template name-template  [option...] input-image...

       didjvu bundle [{-o | --output} output-djvu] [option...] input-image...

       didjvu {--version | --help | -h}

DESCRIPTION

       didjvu uses the Gamera[1] framework to separate foreground/background layers, which can be then encoded into a DjVu file.

       didjvu separate generates images mask(s) for the supplied input image(s). Masks are saved in the PNG format.

       didjvu encode converts the supplied input image(s) to single-page DjVu documents(s).

       didjvu bundle converts the supplied input image(s) to a bundled multi-page DjVu document.

OPTIONS

       didjvu accepts the following options:

   Input, output
       -o, --output=output-djvu
	   Generate a bundled multi-page document. Write the file into output-djvu file instead of standard output.

	   For separate and encode commands this option is allowed only if there is exactly one input file (i.e. exactly one output file).

       --output-template=template
	   Specifies the naming scheme for output files for the separate and encode commands. Please consult the "TEMPLATE LANGUAGE" section for
	   the template language description.

	   This option is mandatory if there is more than one input file (i.e. more than one output file).

       --pageid-template=template
	   Specifies the naming scheme for page identifiers for the bundle command. Please consult the "TEMPLATE LANGUAGE" section for the
	   template language description. The default template is "{base-ext}.djvu".

	   For portability reasons, page identifiers:

	   o   must consist only of lowercase ASCII letters, digits, _, +, - and dot,

	   o   cannot start with a +, - or a dot,

	   o   cannot contain two consecutive dots,

	   o   must end with the .djvu extension.

   Masks
       --loss-level=n
	   Specifies the aggressiveness of the lossy compression for the separate and encode commands. The default is 0 (lossless). Valid values
	   are integers between 0 and 200, inclusive.

	   This option is similar to the -losslevel option of cjb2; please consult the cjb2(1) manual page for details.

       --lossless
	   Synonym for --loss-level=0.

       --clean
	   Synonym for --loss-level=1.

       --lossy
	   Synonym for --loss-level=100.

       -m, --method=method
	   Use the selected method to generate image mask (i.e. separate foreground from background). The following methods should be available:

	   abutaleb
	       Abutaleb locally-adaptive thresholding algorithm

	   bernsen
	       Bernsen thresholding algorithm

	   djvu
	       DjVu thresholding algorithm

	   niblack
	       Niblack adaptive thresholding algorithm

	   otsu
	       Otsu thresholding algorithm

	   sauvola
	       Sauvola adaptive thresholding algorithm

	   shading-subtraction
	       thresholds an image after subtracting a possibly shaded background

		   Note
		   this method requires Gamera >= 3.3.1

	   tsai
	       splitting along a threshold value determined using the Tsai Moment Preserving Threshold algorithm

	   white-rohrer
	       White and Rohrer dynamic thresholding algorithm

	   The default is 'djvu'.

	   Please consult the Gamera documentation[2] for details.

       -p, --pages-per-dict=n
	   For bundle command: if n > 1, compress mask using minidjvu using n pages in one pass. The default is 1.

       --masks, --mask=input-mask
	   Use the pre-generated image masks for the encode and bundle commands.

   Foreground/background quality, resolution
       (These options apply to encode and bundle commands only.)

       -d, --dpi=resolution
	   Specifies the desired resolution to resolution dots per inch. The default is 300 dpi. The allowed range is: 72 <= resolution <= 6000.

       --fg-slices=n
	   Specifies the encoding quality of the IW44 foreground layer. The default is 100.

	   This option is similar to the -slice option of c44; please consult the c44(1) manual page for details.

       --fg-crcb=normal
	   Select normal chrominance encoding of the foreground layer.

       --fg-crcb=half
	   Select half resolution chrominance encoding of the foreground layer.

       --fg-crcb=full
	   Select the highest possible quality for encoding the chrominance information of the foreground layer. This is the default.

       --fg-crcb=none
	   Disable the encoding of the chrominance of the background layer.

       --fg-subsample=n
	   Specifies the foreground/background subsampling ratio. The default is 6. Valid values are integers between 1 and 12, inclusive.

       --bg-slices=n+...+n, --bg-slices=n,...,n
	   Specifies the encoding quality of the IW44 background layer. The default is 74+10+6+7.

	   This option is similar to the -slice option of c44; please consult the c44(1) manual page for details.

       --bg-crcb=normal
	   Select normal chrominance encoding of the background layer. This is the default.

       --bg-crcb=half
	   Select half resolution chrominance encoding of the background layer.

       --bg-crcb=full
	   Select the highest possible quality for encoding the chrominance information of the background layer.

       --bg-crcb=none
	   Disable the encoding of the chrominance of the background layer.

       --bg-subsample=n
	   Specifies the foreground/background subsampling ratio. The default is 3. Valid values are integers between 1 and 12, inclusive.

   XMP support
       (These options apply to encode command only.)

       --xmp
	   Create sidecar XMP[3] metadata.

	       Note
	       This option is experimental!

   Verbosity, help
       -v, --verbose
	   Display more informational messages while converting the file.

       -q, --quiet
	   Don't display informational messages while converting the file.

       --version
	   Output version information and exit.

       -h, --help
	   Display help and exit.

ENVIRONMENT

       The following environment variables affects didjvu:

       TMPDIR

	   didjvu makes havy use of temporary files. It will store them in a directory specified by this variable. The default is /tmp.

TEMPLATE LANGUAGE

   Template syntax
       The template language uses the Python string formatting syntax[4].

   Available field names
       name
	   Input file path.

       name-ext
	   Input file path without file extension.

       base
	   Input file name without directory components.

       base-ext
	   Input file name without directory components and without file extension.

       page, page+N, page-N
	   Page number, optionally offseted by a number N.

SEE ALSO

       djvu(1), djvumake(1), c44(1), cjb2(1), minidjvu(1),

AUTHOR

       Jakub Wilk <jwilk@jwilk.net>
	   Author.

NOTES

	1. Gamera
	   http://gamera.informatik.hsnr.de/

	2. Gamera documentation
	   http://gamera.sourceforge.net/doc/html/binarization.html

	3. XMP
	   http://www.adobe.com/devnet/xmp.html

	4. Python string formatting syntax
	   http://docs.python.org/library/string.html#format-string-syntax

didjvu 0.2.3							    02/01/2012								 DIDJVU(1)