SobelEdgeImg

DESCRIPTION

Performs edge detection using two Sobel kernels. The module performs two independent filtering operations using convolution kernels denoted X and Y, then adds the absolute values of the outputs according to
output = | convolve( input, X ) |  +
| convolve( input, Y ) |
The output is clipped to the valid data range for its word type, for instance [0..255] for byte data and [0..65535] for short data. The two kernels are
     X                        Y
-1  +0  +1               +1  +2  +1
-2  +0  +2               +0  +0  +0
-1  +0  +1               -1  -2  -1
Edge detection by convolution with Sobel kernels is discussed in:

Digital Image Processing, Gonzales, R.C., Wintz, P., Addison Wesley, Second Edition, 1987, p 337.

INPUTS

Port: Img In
Type: Lattice
Constraints: 1..3-D
Source image.

WIDGETS

Port: Bias
Type: Slider
Additive bias.

OUTPUTS

Port: Img Out
Type: Lattice
Constraints: 1..3-D
Edge enhanced filtered image.

KNOWN PROBLEMS

SEE ALSO

LaplaceEdgeImg.
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© The Numerical Algorithms Group Ltd, Oxford UK. 2000