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}
- didjvu separate --output-template name-template [option...] input-image...
DESCRIPTION
didjvu
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).
--page-id-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:
- • must consist only of lowercase ASCII letters, digits, _, +, - and dot,
- • cannot start with a +, - or a dot,
- • cannot contain two consecutive dots,
- • 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
brink
-
Brink and Pendock's minimum-cross entropy method
-
Note
this method requires Gamera ≥ 3.4.0
-
djvu
- DjVu thresholding algorithm
global
- splitting along a global threshold value
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 m[blue]Gamera documentationm[][2] for details.
-x, --param=name=value
-
Set parameter for the binarization method.
This option can be used more than once.
Please consult the m[blue]Gamera documentationm[][2] for details.
-p, --pages-per-dict=n
- For bundle command: if n > 1, compress masks with 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 to preserve the input file resolution, or 300 dpi if resolution metadata is missing. 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 foreground layer.
--fg-subsample=n
- Specifies the foreground 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 background subsampling ratio. The default is 3. Valid values are integers between 1 and 12, inclusive.
XMP support
(These options apply to encode and bundle commands only.)
--xmp
-
Create sidecar
m[blue]XMPm[][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 heavy 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 m[blue]Python string formatting syntaxm[][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 shifted by a number N
NOTES
- 1.
-
Gamera
- m[blue]http://gamera.informatik.hsnr.de/m[]
- 2.
- Gamera documentation
- 3.
-
XMP
- m[blue]https://www.adobe.com/devnet/xmp.htmlm[]
- 4.
-
Python string formatting syntax