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Comparison of Grain Counting Methods

Feature Neural Network Differencing Quick Segmentation
Speed slow medium fast
No. of params 3 2 1
Works with color images yes no no
Ability to separate good medium poor
closely-spaced patterns      
Requires selecting yes no no
representative pattern      
Provides graphs of yes / no yes / yes yes /yes
signal distribution and      
size distribution      
Type of pattern Any Grains/spheres Grains

The neural network algorithm is a modified and greatly simplified version of a hierarchical neural network[6]. With appropriate threshold values, it is possible to count grains or any other pattern such as cells, faces, etc., in the presence of other potentially-interfering objects. To illustrate, we will count occurrences of the letter ``x'' in a simplified image.

The left panel below shows the original image, a combination of x's, y's and z's. The pattern recognition process subtracts pixels that are part of the pattern (in this case the `x's), while tye `y' and `z' are unaffected. This subtraction also allows any patterns obscured by the pattern to be identified on a subsequent pass.


\begin{picture}( 100,100 )(0,10)
\put(50, 10){ \epsfig{file = letters1.ps, widt...
...in }}
\put(170, 10){ \epsfig{file = letters2.ps, width=1.3 in }}
\end{picture}
Pattern recognition in tnimage.


next up previous contents index
Next: Counting patterns with neural Up: Grain counting and pattern Previous: Grain counting and pattern   Contents   Index
root 2006-11-13