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Research on algorithm of image reversible watermarking based on compressed sensing 期刊论文
Journal of Information and Computational Science, 2013, 卷号: 10, 期号: 3, 页码: 701-709
作者:  Zhang, Qiuyu;  Sun, Yuan;  Yan, Yan;  Liu, Hongguo;  Shang, Qichang
收藏  |  浏览/下载:13/0  |  提交时间:2020/11/14
Research of high-speed railway image noise removal based on fast recursive GCV threshold function 会议论文
Chengdu, China, June 12, 2010 - June 13, 2010
作者:  Ma, Hongfeng;  Dang, Jianwu;  Liu, Xin
收藏  |  浏览/下载:14/0  |  提交时间:2020/11/15
Hyperspectral image lossless compression using the 3D set partitioned embedded zero block coding alogrithm 会议论文
作者:  Ying, Hou;  Guizhong, Liu
收藏  |  浏览/下载:2/0  |  提交时间:2019/12/18
Lossless wavelet compression on medical image (EI CONFERENCE) 会议论文
4th International Conference on Photonics and Imaging in Biology and Medicine, September 3, 2005 - September 6, 2005, Tianjin, China
Zhao X.; Wei J.; Zhai L.; Liu H.
收藏  |  浏览/下载:28/0  |  提交时间:2013/03/25
An increasing number of medical imagery is created directly in digital form. Such as Clinical image Archiving and Communication Systems (PACS). as well as telemedicine networks require the storage and transmission of this huge amount of medical image data. Efficient compression of these data is crucial. Several lossless and lossy techniques for the compression of the data have been proposed. Lossless techniques allow exact reconstruction of the original imagery while lossy techniques aim to achieve high compression ratios by allowing some acceptable degradation in the image. Lossless compression does not degrade the image  thus facilitating accurate diagnosis  of course at the expense of higher bit rates  i.e. lower compression ratios. Various methods both for lossy (irreversible) and lossless (reversible) image compression are proposed in the literature. The recent advances in the lossy compression techniques include different methods such as vector quantization  wavelet coding  neural networks  and fractal coding. Although these methods can achieve high compression ratios (of the order 50:1  or even more)  they do not allow reconstructing exactly the original version of the input data. Lossless compression techniques permit the perfect reconstruction of the original image  but the achievable compression ratios are only of the order 2:1  up to 4:1. In our paper  we use a kind of lifting scheme to generate truly loss-less non-linear integer-to-integer wavelet transforms. At the same time  we exploit the coding algorithm producing an embedded code has the property that the bits in the bit stream are generated in order of importance  so that all the low rate codes are included at the beginning of the bit stream. Typically  the encoding process stops when the target bit rate is met. Similarly  the decoder can interrupt the decoding process at any point in the bil stream  and still reconstruct the image. Therefore  a compression scheme generating an embedded code can start sending over the network the coarser version of the image first  and continues with the progressive transmission of the refinement details. Experimental results show that our method can get a perfect performance in compression ratio and reconstructive image.  
Detection and tracking of low contrast targets based on integertype lifting wavelet transform (EI CONFERENCE) 会议论文
ICO20: Remote Sensing and Infrared Devices and Systems, August 21, 2005 - August 26, 2005, Changchun, China
Wang L.; Shen X.; Wang Y.
收藏  |  浏览/下载:11/0  |  提交时间:2013/03/25
This paper presents a method for detecting and tracking of low contrast targets. The new method uses an integer-type lifting wavelet transform and the proposed method doesn't extract patterns similar to a template  but finds parts having the same feature in the targets. We utilize one of integer-type lifting wavelet transforms that contains rounding-off arithmetic for mapping integers to integers. The lifting term contains parameters that are learned by using standard training images of targets. We assume that the targets include many high frequency components. In order to obtain the features of the targets  the lifting parameters are determined by a condition that high frequency components are vanished in wavelet transform. But the condition cannot be determined by the parameters wholly. So  we put an additional condition of minimizing the squared sum of the lifting parameters. The advantage of using integer-type wavelet transform is simple and robust to noise. Simulation illustrated the approach can detect and track the moving targets in dim background. We would test our algorithm in the TV tracking system.  
Matrix factorizations for reversible integer mapping 期刊论文
ieee transactions on signal processing, 2001
Hao, PW; Shi, QY
收藏  |  浏览/下载:4/0  |  提交时间:2015/11/10


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