1. MA model of retina for edge detection & removing noise
Simplifying to apply MA model
(feed forward only)
Retina
Biological Systems Modeling

2. Biological Systems Modeling
Edge Detection
using first order derivatives
using second order derivatives
Biological Systems Modeling

3. Noise effect in Edge Detection
Result: noise filtering is required especially in second order derivatives
Biological Systems Modeling

4. Biological Systems Modeling
Edge Detection (LoG)
Biological Systems Modeling

5. Biological Systems Modeling
Edge Detection (LoG)
A:Original image B:sobel gradient
C:Gaussian smoothing D:Laplasian mask
E:LoG F:Thresholding LoG G:Zero crossing
Biological Systems Modeling

6. Resulting & MA modeling
Thus a simple neuron can apply like a LoG surrounding center Filter :
So , because of non-positive
Terms around the center , shading and overlapping between neurons can be removed.
And each neuron have a Threshold function
Biological Systems Modeling

7. Biological Systems Modeling