Embedding QR Code onto Triangulated Meshes using Horizon Based Ambient Occlusion

Abstract

QR code is a widely used format to encode information through images that can be easily decoded using a smartphone. These devices play a significant role in most people's everyday lives, making the encoded information widely accessible. However, decoding the QR code becomes challenging when significant deformations occur in the label. An easy and quick solution to keep the deformation on a minimum level is to affix the label that contains the QR code onto a developable surface patch of a 3D model. The perspective distortion that can appear is efficiently dealt with during the decoding process. In recent years an alternative method has emerged. In the work of Kikuchi et al., the QR code is embedded onto B‐spline surfaces of CAD models to give more freedom in providing additional information. This method was further improved and extended by Peng et al. embed QR codes onto the surface of general meshes. This paper introduces a solution to embed QR codes onto the surface of general meshes without densely triangulating the selected area of the QR code. It uses the deferred shading technique to extract the surface normals and the depth values around the QR code's user‐given centre. We propose two methods for automatically finding the projection direction even when highly curved areas are selected based on the retrieved information while rendering the model. Besides, we introduce two methods needing a projection direction and a QR code centre to determine a size for automatically embedding the QR code. We propose patterns for decreasing the carving depth of the embedded QR codes, and we use the Horizon‐Based Ambient Occlusion to speed up the engraving process. We validate our method by comparing our results to the outcomes of Peng et al.