고속 푸리에 변환을 기반으로 디지털 이미지 상관법의 분석 속도 향상 알고리즘에 관한 연구
A Study on an Analysis Speed Enhancement Algorithm for the Digital Image Correlation Method Based on Fast Fourier Transform
Digital Image Correlation (DIC) is a measurement method based on image analysis that calculates the correlation between the original reference image and the deformed one. However, an extensive iterated calculation process is required to trace every point on the deformed specimen in the area of interest. The Fast Fourier Transform (FFT) has been adopted to reduce the calculation time, but the FFT method easily loses tracking for large deformation. A new FFT-based correlation analysis algorithm with displacement feedback is proposed to improve the calculation speed of the DIC system and to prevent the correlation coefficient from declining. The calculation rate using the conventional DIC method was compared with that using our new feedback FFT-based approach. This paper demonstrates that the calculation speed of the proposed method was about three times faster than that of the conventional technique. In addition, no tracking failure comes out by our new algorithm even though only FFT-DIC without feedback updating lost tracking over 10% strain.
한국어
디지털 이미지 상관법(DIC)은 reference image와 reference image가 변화된 후의 이미지에 대한 상관관 계를 분석하는 영상 분석 기반의 계측 방법이다. 그러나 변화된 후의 지점을 추적하기 위해 관심 영역에서 변형된 시편의 모든 지점을 추적하려면 광범위한 반복 계산 프로세스가 필요하다. 계산 시간을 줄이기 위해 고속 푸리에 변환(FFT)을 적용했지만 큰 변형에 대한 추적은 쉽지 않다. DIC의 계산 속도를 향상시키고 상관 계수가 감소하 는 것을 방지하기 위해 변위 피드백을 갖춘 새로운 FFT 기반의 상관 분석 알고리즘을 제안하고자 한다. 새로운 FFT 기반의 방법을 기존 DIC를 이용한 계산 속도와 비교하였다. 본 논문에서 제안된 방법의 계산 속도가 기존의 방법보다 약 3배 빠르다는 것을 입증하였다. 또한, 피드백 업데이트 없이 FFT-DIC에서는 10% 이상의 변형율을 추적을 못하지만, 새로운 알고리즘은 추적하는데 실패하지 않는다.
목차
요약 Abstract Ⅰ. Introduction Ⅱ. Digital image correlation 2.1 Principles of the Digital Image Correlation Method 2.2 Principles Image correlation method by using Fast Fourier Transform (FFT) 2.3 The FFT-based image correlation measurement algorithm using a displacement feedback loop Ⅲ. Test procedures and results 3.1 Experimental configuration 3.2 Calculation speed improvement 3.3 Displacement tracking results Ⅳ. Conclusions REFERENCES
키워드
디지털 이미지 상관법고속 푸리에 변환이미지 분석변위변형률Digital Image CorrelationFast Fourier TransformImage analysisDisplacementStrain
Ever since next generation convergence technology became one of the most important industries in the nation, computing professionals have encountered a growing number of challenges. Along with scholars and colleagues in related fields, they have gathered in avariety of forums and meetings over the last few decades to share their knowledge, experiences and the outcome of their research. These exchanges have led to the founding of the International Next-generation Convergence technology (INCA) on December 1, 2015. INCA was registered as an incorporated association under the Ministry of Information and Communications. The main purpose of the organization is to improve our society by achieving the highest capability possible in next generation convergence technology.
간행물
간행물명
차세대융합기술학회논문지 [The Journal of Next-generation Convergence Technology Association]