.TH NIP2 1 "Oct 4 2004"
.SH NAME
nip2 \- image processing with the VIPS library

.SH SYNOPSIS
.B nip2 [filename1 ...]
.br
.B nip2 -s filename [arg1 ...]
.br
.B nip2 -e expression [arg1 ...]

.SH DESCRIPTION
.B nip2
(for New Image Processing) is a tool for manipulating images using the
VIPS image processing library.

There are three principal modes:

.B nip2 [filename1 ...]
.br
  start in GUI mode, loading the named files

.B nip2 -e expression [arg1 ...]
.br
.B nip2 --expression=EXPRESSION [arg1 ...]
.br
  start in no-GUI mode; set main = expression, set list argv to
  ["filename", "arg1", "arg2", ...], set argc to length of list; print
  the value of symbol "main" to stdout; exit

.B nip2 -s filename [arg1 ...]
.br
.B nip2 --script=FILENAME [arg1 ...]
.br
  start in no-GUI mode; read in filename as a set of definitions, 
  set list argv to ["filename", "arg1", "arg2", ...], set argc to 
  length of list; print the value of symbol "main" to stdout; exit; 
  useful for running nip2 as an interpreter on unix

You can use
.B -o
to direct output to a file rather than stdout.

.B -o filename
.br
.B --output=FILENAME
.br
  the value of main is written to the named file. If main is a 
  list, the filename is incremented between objects. You can use 
  the suffix to specify the format and options to write in

Other options provide finer control over startup and shutdown. If you need to
do something strange, don't use -e/-s, use these in combination.

.B -b
.br
.B --batch
.br
  batch (ie. non-GUI) mode

.B -m
.br
.B --no-load-menus
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  don't load menus, for faster startup

.B -a
.br
.B --no-load-args
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  don't load extra command-line arguments

.B -w
.br
.B --stdin-ws
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  load stdin as a workspace

.B -d
.br
.B --stdin-def
.br
  load stdin as a set of definitions

.B -p
.br
.B --print-main
.br
  print the value of main on exit. nip2 will check for a top-level 
  symbol called main, and also check each workspace for a main

Finally some other options are useful for debugging, timing and for generating
strings for internationalisation.

.B -V
.br
.B --verbose
.br
  produce verbose error messages: handy for debugging in batch mode

.B -i
.br
.B --i18n
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  output strings from .def files for internationalisation

.B -v
.br
.B --version
.br
  print version information

.B -c
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.B --benchmark
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  benchmark: no GUI, just start up and shut down

.B -t
.br
.B --time-save
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  time saves: after every image save a popup tells you the time the 
  save took in seconds

.B -T
.br
.B --test
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  test: start up (including any arg processing), test for any errors, 
  and exit with an error code if any occured. Useful for running 
  automated tests.

.B -x PREFIX
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.B --prefix=PREFIX
.br
  set install prefix: start up as if nip2 had been installed to PREFIX.
  Useful for running automated tests without installing the thing.

.SH EXAMPLES

  nip2 fred.jpg

Start nip2, loading fred.jpg.

  nip2 -e "2 + 2"

Prints 4 to stdout.

  nip2 -e "99 + Image_file argv?1" -o result.png fred.jpg

Load argv1 (fred.jpg), add 99, output to result.png.

  nip2 -e "Matrix [[1,2],[4,5]] ** -1" -o poop.mat

Invert the 2x2 matrix and write the result to poop.mat.

.SH COPYRIGHT
2008 (c) Imperial College, London