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
--output=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.
-b
--batch
batch (ie. non-GUI) mode
-m
--no-load-menus
don't load menus, for faster startup
-a
--no-load-args
don't load extra command-line arguments
-w
--stdin-ws
load stdin as a workspace
-d
--stdin-def
load stdin as a set of definitions
-p
--print-main
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.
-V
--verbose
produce verbose error messages: handy for debugging in batch mode
-i
--i18n
output strings from .def files for internationalisation
-v
--version
print version information
-c
--benchmark
benchmark: no GUI, just start up and shut down
-t
--time-save
time saves: after every image save a popup tells you the time the save took in seconds
-T
--test
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.
-x PREFIX
--prefix=PREFIX
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.
2008 (c) Imperial College, London