As an example, figure 3.3 will print the width and height of an image stored on disc.
To compile this example, use:
cc `pkg-config vips-7.10 --cflags --libs` myfunc.c
As a slightly more complicated example, figure 3.3 will calculate the photographic negative of an image.
The call to im_updatehist()
adds a line to the Hist
field in
out
, noting the invocation of this program, its arguments, and the
time and date at which it was run. It is the application's responsibility
to keep Hist
up-to-date -- the image processing functions do not
use this field. You may also find im_histlin()
helpful. It has type:
void im_histlin( IMAGE *im, const char *fmt, ... )
It formats its arguments as printf()
and appends the string formed
to the Hist
string.