im_ceil(3)
for each pixel, find the smallest integral value not less than
SYNOPSIS
#include <vips/vips.h>
int im_ceil( in, out )
IMAGE *in, *out;
DESCRIPTION
im_ceil(3)
finds the smallest integral value not less than. Copy for integer types,
call
ceil(3) for float and complex types. Output type == input type.
RETURN VALUE
The function returns 0 on success and -1 on error.