| .TH IM_SIGN 3 "July 2002" |
| .SH NAME |
| im_sign \- find the unit vector in the direction of value |
| .SH SYNOPSIS |
| #include <vips/vips.h> |
| |
| int im_sign( in, out ) |
| .br |
| IMAGE *in, *out; |
| .SH DESCRIPTION |
| .B im_sign(3) |
| finds the unit vector in the direction of the pixel value. For non-complex |
| images, it returns a signed char image with values -1, 0, and 1 for negative, |
| zero and positive pixels. For complex images it returns a |
| complex normalised to length 1. |
| .SH RETURN VALUE |
| The function returns 0 on success and -1 on error. |
| .SH SEE ALSO |
| im_abs(3), im_cmulnorm(3), im_c2amph(3) |
