OBJECT LENGTH AND AREA CALCULATIONS ON THE DIGITAL IMAGE
Alojz Suhadolnik, Franc Kosel · 2008
The parts of structure elements and other products can be photographed with a digital camera. The photo is then analyzed and the appreciation of quality of the product relates to the magnitude and shape of irregularities, i.e. their area and extent and the relationship between them. The paper introduces a sample-anchoring method for estimating the arc length and the area of a closed planar curve consisting of the geometrically ordered data points. An adjunctive pixel is appended to each pixel. The adjunctive pixel is computed by the use of a changeable convolution mask, where the pixel anchoring into the neighborhood of the original pixel is taken into account. The curve is approximated by two polygons. Vertices of the first one are adjunctive pixels and the vertices of the second one are convolve pixels. The sample anchoring method uses three parameters. The first one models the convolution mask, the second and the third one model the neighborhood of the pixel and the stop criterion of the convolution process.