nip2 man page

nip2 — image processing with the VIPS library


nip2 [filename1 ...]
nip2 -s filename [arg1 ...]
nip2 -e expression [arg1 ...]


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

There are three principal modes:

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

nip2 -e expression [arg1 ...]
nip2 --expression=EXPRESSION [arg1 ...]
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

nip2 -s filename [arg1 ...]
nip2 --script=FILENAME [arg1 ...]
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 -o to direct output to a file rather than stdout.

-o filename
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.

batch (ie. non-GUI) mode

don't load menus, for faster startup

don't load extra command-line arguments

load stdin as a workspace

load stdin as a set of definitions

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.

produce verbose error messages: handy for debugging in batch mode

output strings from .def files for internationalisation

print version information

benchmark: no GUI, just start up and shut down

time saves: after every image save a popup tells you the time the
save took in seconds

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.

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


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.


Oct 4 2004