Improvement method of high-temperature digital image correlation measurement accuracy based on image processing

With the increasing application of digital image correlation (DIC) technology in the field of high-temperature measurement, thermal radiation and disturbance in high-temperature environment restrict the development of high-temperature DIC technology. In this study, we propose a method based on image processing to improve the measuring accuracy of DIC technique of high temperature for solving the above mentioned problems. Firstly, the image dehazing enhancement processing and the gray scale range stretching processing are used to eliminate the influence of the thermal radiation background light to enhance the image contrast. Then, the inverse filtering image recovery processing is used to eliminate the effect of the thermal perturbation. Lastly, a series of high temperature image acquisition and thermal disturbance elimination experiments at 1200 degrees C are conducted. The image collected by the camera is enhanced and restored according to the above mentioned image processing method. Experimental results show that this method can acquire high-contrast clear images under high temperature conditions, effectively eliminate the interference of thermal disturbance noise in high temperature measurement and improve the measurement accuracy.