IMPROVEMENT OF THE ALGORITHM FOR DETERMINING THE GEOMETRIC DIMENSIONS OF OBJECTS IN A PLANE USING THE SCANLINE METHOD

Abstract

The object of research in the paper is the spline analysis of the scan line. The purpose of the work is the development of an improved algorithm for scanning contours and determination of geometric parameters of samples in the plane using spline interpolation tools. An overview of a number of existing studies in the field of software solutions for the definition and analysis of contours in images is presented. Trends in the development of algorithmic and neural network systems for finding contours of objects have been revealed, but the task of metrological assessment of such objects is poorly developed and can be investigated. The method of finding points on the contour was developed using spline interpolation to the vector of pixels of the scanline with the detection of points of contrast transition through the analysis of the points of change of sign of the piecewise function of the spline on the module of the function of the derivative of the function of the spline, taking into account the contrast difference between the tangent points on the investigated image of the control object or measurement. The appropriate visualization for the case of a simple scanline with mathematical testing based on the SciLab system is given. Based on the methodology, an algorithm for scanline analysis was developed and a software tool was developed that implements this algorithm.The development is based on a renderer that implements the OpenGL standard using elements of the Boost library to perform spline interpolation, as well as GTK to obtain an enclosing rectangle of minimum area by the rotary caliper method. The reliability of the work results was evaluated, with results that are acceptable for engineering use of the software under the condition of correct configuration. Testing of the software tool was performed on the basis of a set of test images, which included oval ideal test samples without gradient transition zones and with binary color, model samples rendered by Cycles rendering tools in Blender 3D, and photographic test samples.