Morphological operations.html (2389B)
1 <?xml version="1.0" encoding="UTF-8"?> 2 <!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd"> 3 <html><head><link rel="stylesheet" href="sitewide.css" type="text/css"><meta http-equiv="Content-Type" content="text/html; charset=UTF-8"/><meta name="exporter-version" content="Evernote Mac 7.5.2 (457164)"/><meta name="altitude" content="0.3445475697517395"/><meta name="author" content="Alex Balgavy"/><meta name="created" content="2017-12-19 20:06:13 +0000"/><meta name="latitude" content="52.37343104980074"/><meta name="longitude" content="4.836051095350311"/><meta name="source" content="desktop.mac"/><meta name="updated" content="2017-12-19 20:12:30 +0000"/><title>Morphological operations</title></head><body><div><span style="font-weight: bold;">Morphologic operations</span></div><div>Useful for analysing shapes in images</div><div>Used on binary images</div><div>Operates by applying a kernel (structuring element of 0 and 1) to each pixel in input</div><div>there is a designated center pixel</div><div>instead of multiplication/addition, it is applied using a hit (dilation) or fit (erosion) operation</div><div><br/></div><div>procedure:</div><ol><li>Structuring element is placed on top of image</li><li>Center of structuring element is placed at position of pixel in focus</li><li>The value of that pixel is calculated by applying structuring element</li></ol><div><br/></div><div>operations</div><ul><li>dilation (increase in size) — center structuring element on each 0 pixel in image. if any in neighbourhood is 1, pixel is switched to 1.</li></ul><blockquote style="margin: 0 0 0 40px; border: none; padding: 0px;"><div><img src="Morphological%20operations.resources/screenshot_1.png" height="316" width="488"/><br/></div></blockquote><ul><li>erosion (decrease in size) — center structuring element on each 1 pixel in image. if any in neighbourhood is 0, pixel is switched to 0.</li></ul><blockquote style="margin: 0 0 0 40px; border: none; padding: 0px;"><div><img src="Morphological%20operations.resources/screenshot.png" height="328" width="500"/><br/></div></blockquote><ul><li>opening (erosion => dilation) — removes small, isolated noisy objects</li><li>closure (dilation => erosion) — removes small hole and join narrow isthmuses between objects</li></ul><div><br/></div></body></html>