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Andrey
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Файл:(EOD).Software topics.pdf
page 164
14.7.1 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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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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14.8 EDGE DETECTION
•An image (already filtered) can be checked to find a sharp edge between the foreground and background intensities.
•Let’s assume that the image below has been prefiltered into foreground (1) and background (0). An edge detection step is then performed.