Edge Detection Of Optical Subaperture Based On Fractal Dimension

Optical synthetic aperture imaging technology is an effective method improve the imaging resolution by increasing the aperture of the system.Compared with the traditional monolithic mirror imaging system,there is often a gap between the mirrors of synthetic aperture imaging system.The gap cause the image at the edge more complex.As a result,in order to achieve effective stitching of subapertures without losing effective information,it is necessary to detect the edge of the image.Since its inception,fractal theory has solved many difficult problems which traditional methods can not deal with,and provided a new idea for image processing fields.Fractal dimension,as the metric feature of fractal theory,can characterize the complexity of image surface texture,which provides a new way for edge detection of image.Based on the traditional edge detection algorithm,combined with the problems existing in the differential box-counting method,this paper proposes an edge detection algorithm based on the improved differential box-counting method.Firstly,this algorithm proposes an adaptive differential box-counting method to solve the problem that the traditional differential box-counting method is inaccurate in the statistics of box number.Then,a new image super-resolution reconstruction algorithm based on convolution neural network is proposed to solve the problem that the fractal dimension can not be accurately estimated under the small image window.Compared with the traditional interpolation algorithm,the proposed super-resolution reconstruction algorithm can keep the scaling invariance of fractal dimension well.At last,the paper evaluates the algorithm based on the method of reference map,and the results show that the proposed algorithm has high accuracy and good continuity;in addition,it has good anti-noise performance.Finally,based on the characteristics of optical subaperture image,the proposed edge detection algorithm based on fractal dimension is applied to optical subaperture image,and finally realized the accurate detection of the edge of optical subaperture image.In addition,the research work of this paper lays a foundation for the subsequent research of the subaperture boundary effect.