一种改进的基于压缩感知的差分关联成像方法

Improvement of Compressive Sensing Based Differential Correlated Imaging

基于压缩感知的差分关联成像虽然能够以较少的采样次数高质量地恢复出物体的信息,但在图像重构过程中存在矩阵过大,占用计算机内存大,重构时间长的问题。为此提出了有数据预处理的改进压缩感知差分关联成像方案,首先鉴于光强涨落特性得到部分测量数据构造出初始字典D0,然后通过学习得到字典D作为传感矩阵,最后通过正交匹配追踪恢复出物体的信息。实测"单缝"实验数据成像结果表明,与传统的压缩感知差分关联成像相比,该方案以更少的测量数据恢复出高清晰的像,成像效率和质量都得到了提高,降低了对系统硬件的过高要求,缩短了图像重构时间,从而将有助于加快量子成像技术向实用化转化的步伐。

Compressive sensing based differential correlated imaging can reconstruct high quality object image using less number of samples than traditional correlated imaging method,but the former method still has the problem that large computation memory space and it need long image reconstruction time.To solve the problem,this paper proposed an improved differential compressive correlated imaging scheme using the fact that the fluctuations intensity of the optical field influences the contrast quality of the reconstructed image.The scheme can be described as following:First,the measurement data was preprocessed and only the measurement data that is higher than the average value were used to construct the initial dictionary by re-ordering the selected data and extend them to be vector.Then using the training sample,we got the learned initial dictionary D0 as the sensing matrix,next with the learned D0,and using K-means singular value decomposition(K_SVD)algorithm we obtained the updated dictionary Dand the corresponding sparse matrix.Finally,the object image information was gotten by orthogonal matching pursuit algorithm.Real experimental data of the object'single slot'and different imaging method were used,the imaging results show that the improved scheme can reconstruct high-definition images using less sample data amount(about 300samplings)than the traditional compressive sensing based differential correlated imaging method(about thousands of samplings).Thus the new scheme greatly improves the imaging efficiency and image quality,reduces the excessive demands of the system storage hardware,and shortens the image reconstruction time.In addition,another object's image can be obtained by single optical path measuring provided that the parameters of optical source and distances unchanged,which can reduce the hardware complexity of correlation imaging.All this benefits will make the correlation imaging to be more practical for real applications.