Name

imconv — 2D convolution

Calling Sequence

Outm = imconv(Img, mask [, form])

Parameters

Img
M x N Grayscale (intensity) image in any range.
mask
n x n matrix, n odd. This is the spatial convolution kernel.
form
determines the size of Outm. It assumes be one of the following values 'same' Outm has the same size as the original 'full' Outm contains the full convolution, (M+n-1) 'valid'

Parameters

Outm
The convolved matrix (grayscale image).

Description

Function imconv performs 2D spatial convolution of a grayscale image and a mask.

edge(Img)
Detects edges in Img, using the sobel gradient estimator, 0.5 threshold level and in both horizontal and vertical directions.

The other parameters are optional and non-positional. That is, they may be passed to the function by their name. The following example illustrates this.

Examples

       initial_dir = PWD;
       chdir (SIPDIR + 'images');
       // Detect horizontal lines
       h = [ -1    -1 -1
         2     2  2
        -1    -1 -1]
       img = imread('gra.jpg');
       res = imconv(img,h);
       imshow(res,[]);
       // Detect diagonal lines
       d = [ -1    -1  2
        -1     2 -1
         2    -1 -1]
       res = imconv(img,d);
       imshow(res,[]);
       chdir(initial_dir);

Authors

Ricardo Fabbri <ricardofabbri (AT) users DOT sf DOT net>, with help from
Scilab Group <Scilab@inria.fr>

Availability

The latest version of the Scilab Image Processing toolbox can be found at

http://siptoolbox.sourceforge.net

See Also

mkfilter , edge