Tetrolet域卫星云图分块压缩感知(英文)  

Block Compressed Sensing of Satellite Cloud Images Based on Tetrolet Transform

作　　者：何艳[1] 金炜[1] 刘箴[1] 符冉迪[1] 尹曹谦[1] 

机构地区：[1]宁波大学信息科学与工程学院,浙江宁波315211

出　　处：《光电工程》2014年第5期19-27,共9页Opto-Electronic Engineering

基　　金：国家自然科学基金(61271399,61373068);浙江省自然科学基金项目(Y1111061);宁波市自然科学基金(2011A610192,2013A610055);宁波市科技创新团队研究计划(2011B81002);宁波大学科研基金(XYL1200);宁波大学研究生教育改革研究重点项目(JGZDI201202)

摘　　要：针对卫星云图数据量大,但传输通道和存储空间相对狭小的问题,本文提出了一种基于Tetrolet变换的卫星云图分块压缩感知方法。该方法将Tetrolet变换引入压缩感知的稀疏表示环节,以刻画卫星云图细节丰富,纹理复杂的特性,而且将分块压缩感知与平滑投影Landweber迭代方法结合用于云图重构,以提高计算效率。同时,为了进一步提高重构云图的质量,本文对云图的稀疏表示提出了另一种改进方案,首先对原始云图进行拉普拉斯金字塔分解,将得到的低频分量和高频分量分别进行分块及采样,并对低频及高频分量分别进行离散小波变换(DWT)及Tetrolet变换以实现稀疏表示,此不仅可以发挥不同稀疏变换各自的优点,而且充分利用了Tetrolet变换在表示云图方向纹理和边缘等重要信息方面的优势。实验结果表明,在相同采样率下,本文方法的重构结果明显优于直接用Tetrolet,DWT,Contourlet和DCT变换对卫星云图进行稀疏表示的重构结果。Due to the difficulties caused by large satellite cloud image data with limited transmission channel and storage space, an approach of block compressed sensing of satellite cloud images is proposed based on Tetrolet transform. This approach introduces Tetrolet transform into the sparse representation step of compressed sensing which can depict the detail and texture structure of satellite cloud image well, and combines block compressed sensing with smooth projection Landweber iteration method to accomplish image reconstruction which can improve the computational efficiency. Meanwhile, in order to further improve the quality of reconstructed cloud images, another improvement scheme for the sparse representation of cloud images is proposed. Firstly, a layer of Laplacian pyramid decomposition of the original image is taken, and the low frequency component and high frequency component obtained are divided into blocks and sampled respectively. Then, the low frequency component is represented by Wavelet transform, while the high frequency component is represented by Tetrolet transform, which can not only play the advantage of different sparse representation, but also make full use of the advantages of Tetrolet transform in expressing the important information of cloud images, such as directional texture and edge information. The experimental results show that the reconstruction quality of the proposed method is obviously superior to Tetrolet, DWT, Contourlet and DCT sparse representation methods under the same sampling rate.

关 键 词：Tetrolet变换 分块压缩感知 稀疏表示 卫星云图 

分 类 号：TP751[自动化与计算机技术—检测技术与自动化装置]