1

NAME
SYNOPSIS
PARAMETERS
DESCRIPTION
EXAMPLE
AUTHORS
AVAILABILITY
SEE ALSO

NAME

angle - gradient direction of edges

SYNOPSIS

theta = angle(DeltaX, DeltaY)

PARAMETERS

DeltaX and Delta Y
M x N intensity images, resulting from convolution with gradient masks in two orthogonal directions
theta
Intensity image. Each pixel has the angle of the approximated gradient, in radians. Where DeltaX is zero, theta is taken as PI/2.

DESCRIPTION

The function angle obtains the gradient direction "theta" from images yielded from convolution with gradient masks in direction x and y (Deltax and Deltay, respectively).

EXAMPLE

initial_dir = PWD;
chdir (SIPDIR + 'images');

Img = imread('disks.bmp');
xbasc()
imshow(Img,2);
Dx = edge(Img,thresh=-1, direction='horizontal');
Dy = edge(Img,thresh=-1, direction='vertical');
t = angle(Dx,Dy);
imshow(t,[])

chdir(initial_dir);

AUTHORS

Ricardo Fabbri <rfabbri@if.sc.usp.br>

AVAILABILITY

The latest version of the Scilab Image Processing toolbox can be found at
http://siptoolbox.sourceforge.net

SEE ALSO

edge