| .TH IM_GRAD_X 3 "08 January 2008" |
| .SH NAME |
| im_grad_x, im_grad_y \- find horizontal or vertical differences |
| .SH SYNOPSIS |
| .nf |
| .B #include <vips/vips.h> |
| .sp |
| .BI "int im_grad_x( IMAGE " "*in" ", IMAGE " "*out" " ); |
| .br |
| |
| .BI "int im_grad_y( IMAGE " "*in" ", IMAGE " "*out" " ); |
| .fi |
| .SH DESCRIPTION |
| .B im_grad_x(3) |
| generates an image where the value of each pixel is the difference between horizontally ajacent pixels in the input |
| image. The output has the same height as the input and one pixel less width. |
| .PP |
| .B im_grad_y(3) |
| generates an image where the value of each pixel is the difference between vertically ajacent pixels in the input |
| image. The output has the same width as the input and one pixel less height. |
| .PP |
| In both cases, the input can be any uncoded integer type, and the output is signed 32 bit integer. |
| .SH RETURN VALUE |
| The functions returns 0 on success and -1 on error. |
| .SH COPYRIGHT |
| .br |
| Copyright 2008, Nottingham Trent University. |
| .SH AUTHOR |
| Tom Vajzovic |
