Instance Segmentation and Contour Extraction Method for Open Curves in Engineering Drawings

Abstract Engineering drawing is a universal language that enables engineers to accurately understand design intentions.To accurately understand the intent of the design, it is necessary to segment the engineering drawing into different instances.However,segmenting drawings with dimension details is challenging due to irregular components, shapes, and annotations.These drawings often have different views with small details such as dimension lines and annotations,especially in the package drawing. To obtain single views with dimension lines from open curve in different viewing angles,this paper presents a method integrating the Segment Anything Model (SAM) ,edge detection and path finding algorithms.First, the initial masks are obtained by segmenting drawings using SAM. Then, morphological processing is used to enhance mask quality.Lastly,pixel path search algorithms are used to refine the outer contours and region details. Experiments show that this approach significantly improved segmentation accuracy, providing an effective viewing of the package drawings.