| 摘要 |
FIELD: textile, paper. ^ SUBSTANCE: method for determining textile chafe mark properties as per computer picture can be used during analysis of textile fibre structure in order to investigate its properties by means of laboratory tests. According to the method there determined is chafe mark characteristic showing total length of hairs; fibre is wound on the board of contrast colour with constant pitch and tension; the prepared fibre specimen is laid on the working surface of scanner so that longitudinal fibre axis is perpendicular to light-sensitive element of scanner; there obtained is fibre section picture by scanning in the specified direction and digital values corresponding to its brightness. Then matrix of pixel brightness values is built, then those values are summed as per columns of the matrix, fibre stem section is pointed out by applying the filtration in upper threshold brightness level obtained by building a brightness histogram. In the same way there pointed out is fibre hair section in lower threshold brightness level, the picture is cleaned from the sections characterising the occasional non-uniformity of scanning surface by applying object search operations and calculation of their signs, and there built is central line of fibre picture and a curve in sections on both sides from fibre stem, which corresponds to the number of light pixels in each column of matrix and represents the junction of relative density of hairs located throughout the fibre length without taking into account a fibre stem section. Left part of curve is mirrored to the right one, a point is marked in curves by calculating the derivative of those curves, and limits of zones of dense, informative and occasional hairs are determined with cross points of a tangent to a curve built through the above calculated point and with drawn horizontal lines correspondingly to maximum and minimum number of pixels. Number of hairs in the section is determined by identification of a dressing point and by investigating the area around it; total length of hairs is calculated by adding the number of pixels in each column minus pixels of fibre stem section. Chafe mark radius is measured by averaging pixel brightness values of fibre hair sections. ^ EFFECT: enlarging functional capabilities, decreasing errors and increasing objectivity of determining chafe mark properties. ^ 6 dwg |
