tailieunhanh - Báo cáo hóa học: " A Novel Algorithm of Surface Eliminating in Undersurface Optoacoustic Imaging"

Tuyển tập báo cáo các nghiên cứu khoa học quốc tế ngành hóa học dành cho các bạn yêu hóa học tham khảo đề tài: A Novel Algorithm of Surface Eliminating in Undersurface Optoacoustic Imaging | EURASIP Journal on Applied Signal Processing 2004 17 2684-2695 2004 Hindawi Publishing Corporation A Novel Algorithm of Surface Eliminating in Undersurface Optoacoustic Imaging Yulia V. Zhulina Vympel Interstate Joint Stock Corporation . Box 83 Moscow 107000 Russia Email yuliajulina@ Received 7 January 2003 Revised 25 April 2004 Recommended for Publication by Xiang-Gen Xia This paper analyzes the task of optoacoustic imaging of the objects located under the surface covering them. In this paper we suggest the algorithm of the surface eliminating based on the fact that the intensity of the image as a function of the spatial point should change slowly inside the local objects and will suffer a discontinuity of the spatial gradients on their boundaries. The algorithm forms the 2-dimensional curves along which the discontinuity of the signal derivatives is detected. Then the algorithm divides the signal space into the areas along these curves. The signals inside the areas with the maximum level of the signal amplitudes and the maximal gradient absolute values on their edges are put equal to zero. The rest of the signals are used for the image restoration. This method permits to reconstruct the picture of the surface boundaries with a higher contrast than that of the surface detection technique based on the maximums of the received signals. This algorithm does not require any prior knowledge of the signals statistics inside and outside the local objects. It may be used for reconstructing any images with the help of the signals representing the integral over the object s volume. Simulation and real data are also provided to validate the proposed method. Keywords and phrases optoacoustic imaging surface laser maximum likelihood. 1. INTRODUCTION The task of reconstructing the spatial configuration of the sources using their scattered wideband signals received outside the area of the sources location is that of great theoretical and practical interest for .