A method for segmentation of overlapped bubbles segmentation and contour reconstruction was proposed based on the curve concave-convex transformation and circle fitting in order to identify overlapped bubbles of gas-liquid two-phase flow when the gas phase ratio is large. The bubble image was pre-processed, including the noise that was filtered by the Gauss filter, and the foreground that was separated according to the adaptive threshold. The pre-segmented image was obtained. Then the contour was extracted by the Canny algorithm. The curve was smoothed by the Gaussian function. The distance between contour points and the centroid was calculated. The curve was analyzed by concave-convex transformation characteristic. The segmentation path was selected on each of the two concave points. The bubble contour was reconstructed by the least square circle fitting interpolation algorithm, and the bubble segmentation and reconstruction image was obtained. Experimental results show that the proposed algorithm is an effective algorithm for the segmentation and reconstruction of overlapped bubbles, which has high performance.
MU Jing-jing, ZHAO Xin-yue, HE Zai-xing, ZHANG Shu-you. Contour reconstruction of overlapped bubbles based on concave-convex transformation and circle fitting. JOURNAL OF ZHEJIANG UNIVERSITY (ENGINEERING SCIENCE), 2017, 51(4): 714-721.
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