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Jack H.Integration and automation of manufacturing systems.2001.pdf
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page 487

17.7 FILTERING

Filtering techniques can be applied,

-thresholding

-laplace filtering

-fourier filters

-convolution

-histograms

-neighborhood averaging

17.7.1 Thresholding

• Thresholding basically sets a transition value. If a pixel is above the threshold, it is switched

fully on, if it is below, it is turned fully off.

Original Image

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an array of pixel brightness

It can be difficult to set a good

threshold value, and the results are prone

to noise/imperfections in the image.

e.g. Threshold = 2

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e.g. Threshold = 5

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17.8 EDGE DETECTION