Proc. SPIE. 8005, MIPPR 2011: Parallel Processing of Images and Optimization and Medical Imaging Processing
KEYWORDS: Image processing algorithms and systems, Signal to noise ratio, Lithium, Magnetic resonance imaging, Image segmentation, Image processing, Computing systems, Medical imaging, Numerical analysis, Data processing
Medical images have the characteristics of high noise and blurred edges, which makes them difficult to segment using
traditional segmentation methods. The level set algorithm, which is a commonly used method for medical image
segmentation, is restricted in use mainly due to the extremely intensive computation during the iterative contour
evolution. The paper proposes some criteria of loop iteration break for the level set algorithm, making it possible to
adaptively adjust the number of iterations to the specific characteristics of various medical images, so that the contour
evolution can be terminated appropriately. Meanwhile, we change the step length of the iteration according to the
previous loop iteration result, making it possible to decrease the number of iterations needed. To decrease the
computational workload, we also restrict the iteration to a certain part of the image instead of the whole image.
Automatic magnetic particle inspection based vision system using CCD camera is a new development of magnetic particle inspection. A vision system using linear CCD cameras in semiautomatic fluorescent magnetic particle inspection of axles of railway wheelsets is presented in this paper. The system includes four linear CCD cameras, a PCI data acquisition & logic control card, and an industrial computer. The unique characteristic of striation induced by UV light flicker in scanning image acquired by linear CCD camera are investigated, and some digital image processing methods for images of magnetic particle indications are designed to identify the cracks, including image pre-processing using wavelet, edge detection based connected region using Candy operator and double thresholds. The experimental results show that the system can detect the article cracks effectively, and may improve inspection quality highly and increase productivity practically.