The Feasibility of Identifying Defects Illustrated on Building Facades by Applying Thermal Infrared Images with Shadow

Pei-Hsun Tsai,Yishuo Huang,Jung-Hsing Tai

doi:10.3390/proceedings2019027003

Abstract

Infrared thermography (IRT) has been widely employed to identify the defects illustrated in building facades. However, the IRT covered with a shadow is hard to be applied to determine the defects shown in the IRT. The study proposed an approach based on the multiplicated model to describe quantitively the shadow effects, and the IRT can be segmented into few classes according to the surface temperature information recorded on the IRT by employing a thermal infrared camera. The segmented results were compared with the non-destructive method (acoustic tracing) to verify the correctness and robustness of the approach. From the processed results, the proposed approach did correctly identify the defects illustrated in building facades through the IRTs were covered with shadow.

Highlights

Infrared thermography (IRT) can be used to surface inspection
While an image segmentation technique is used on the IRT covered with shadow effects, the shadow will interfere with the segmented results such that the segmented results are corrupted
Can the IRT cover with shadow effects be analyzed to identify the defects with image segmentation? This paper proposes an approach to analyze IRT with shadow effects by employing the multiplicative model

Summary

Introduction

Infrared thermography (IRT) can be used to surface inspection. Image segmentation is a crucial step in interpreting the visual information from the recorded images. IRT usually can be segmented into several regions such that the surface temperature differences can be applied to identify the defects. While an image segmentation technique is used on the IRT covered with shadow effects, the shadow will interfere with the segmented results such that the segmented results are corrupted. Can the IRT cover with shadow effects be analyzed to identify the defects with image segmentation? This paper proposes an approach to analyze IRT with shadow effects by employing the multiplicative model. The proposed approach applies the image segmentation model proposed by Vese and Chan, and the iteration scheme proposed by Zhang [2] et al to segment the IRT with shadow and the shadow effects can be approximated.

Methods

Materials and Processed Results

Conclusions