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	A multiscale spatio-temporal framework to regionalize annual precipitation using k-means and self-organizing map technique 期刊论文 OAI收割 JOURNAL OF MOUNTAIN SCIENCE, 2018, 卷号: 15, 期号: 7, 页码: 1481-1497 作者: Roushangar, Kiyoumars; Alizadeh, Farhad \| 收藏 \| 浏览/下载：17/0 \| 提交时间：2020/09/29 Precipitation Discrete wavelet transform (DWT) k-means Self Organizing Map (SOM) Iran
	Image coding using wavelet-based compressive sampling (EI CONFERENCE) 会议论文 OAI收割 2012 5th International Symposium on Computational Intelligence and Design, ISCID 2012, October 28, 2012 - October 29, 2012, Hangzhou, China 作者: Li J.; Li J.; Li J. 收藏 \| 浏览/下载：45/0 \| 提交时间：2013/03/25 In this paper we proposed a novel coding scheme is proposed using wavelet-based CS framework for nature image. First two-dimension discrete wavelet transform (DWT) is applied to a nature image for sparse representation. After multi-scale DWT the low-frequency sub-band and high-frequency sub-bands are re-sampled separately. According to the statistical dependences among DWT coefficients we allocate different measurements to low- and high-frequency component. Then the measurements samples can be quantized. The quantize samples are entropy coded and forward correct coding (FEC). Finally the compressed streams are transmitted. At the decoder one can simply reconstruct the image via l1 minimization. Experimental results show that the proposed wavelet-based CS scheme achieves better compression performance against the relevant existing solutions.
	A new spaceborne compression approach for remote sensing imagery (EI CONFERENCE) 会议论文 OAI收割 ICO20: Remote Sensing and Infrared Devices and Systems, August 21, 2005 - August 26, 2005, Changchun, China 作者: Xu S. 收藏 \| 浏览/下载：27/0 \| 提交时间：2013/03/25 After analyzing advantages and disadvantages of these typical encoding methods: SPIHT and VQ a "DWT+MRLE" approach for spaceborne data compression was proposed in this paper. This approach includes two steps: Discrete Wavelet Transform (DWT) and Modified Run Length Encoding (MRLE). The former used CDF9/7 biorthogonal wavelet filters to powerfully get rid of correlation between pixels in imagery. The later put enlightening information into the lowest bit of some key-position transform coefficients. Consequently CDF9/7 and MRLE together make hardware platform remain high real-time capability and help reconstructed images keep good fidelity with PSNR being about 40dB compared with the original ones. Comparison between experimentations on SPOT4's low-spatial-resolution (10m) imagery and Ikonos2's high-spatial-resolution (1m) imagery shows this "DWT+MRLE" method having better performance for remote-sensed imagery especially those of higher resolution. Although inferior to 8:1 Compression Ration (CR) here near 5:1 is greater than France SPOT5's 3:1 and American Ikonos2's 11:2.6 on-board data compression. More important this method having less computational amount is good for spaceborne capability of real time. The consumed time of different image size is also presented in this paper based on TI TMSC6416 DSP chip with 600MHz CPU cycle clock.
	A new segmentation method of CR images based on discrete wavelet transform and mathematics morphology (EI CONFERENCE) 会议论文 OAI收割 ICO20: Optical Information Processing, August 21, 2005 - August 26, 2005, Changchun, China 作者: Li Z.; Li Z. 收藏 \| 浏览/下载：68/0 \| 提交时间：2013/03/25 In this paper we propose a segmentation method of CR(computed radiography) images with being rid of under-segmentation and over-segmentation. An under-segmentation occurs when pixels belonging to different objects are grouped into a single region. Such errors are the most dangerous because they can invalidate the whole segmentation process. The phenomenon always takes place when we segment CR images because of the principle of CR. In order to depressed under-segmentation we enhance the CR images using DWT (discrete wavelet transform) to get more detail of CR image features. As we enhance the CR image the over-segmentation maybe occurs. Compared with under-segmentation the over-segmentation occurs when a single objects is subdivided by segmentation into several region. For the purpose of preventing from the over-segmentation we present a scheme for enhanced CR images based on watershed algorithm that solves over-segmentation problem. We use marker-based watershed algorithm. Together with gradient image and marker image watershed segmentation can make sure to partition CR image into meaningful object and avoid further segmentation of homogeneous regions. The result of the proposed algorithm are compared with those of other standard methods. Experiments have shown a better result and indeed solved under-segmentation and over-segmentation problems.
	a novel synchronization invariant audio watermarking scheme based on dwt and dct 期刊论文 OAI收割 IEEE TRANSACTIONS ON SIGNAL PROCESSING, 2006, 卷号: 54, 期号: 12, 页码: 4835-4840 Wang Xiang-Yang; Zhao Hong \| 收藏 \| 浏览/下载：22/0 \| 提交时间：2011/07/13 audio watermarking discrete cosine transform (DCT) discrete wavelet transform (DWT) synchronization
	a novel synchronization invariant audio watermarking scheme based on dwt and dct 期刊论文 OAI收割 IEEE TRANSACTIONS ON SIGNAL PROCESSING, 2006, 卷号: 54, 期号: 12, 页码: 4835-4840 Wang Xiang-Yang; Zhao Hong \| 收藏 \| 浏览/下载：22/0 \| 提交时间：2011/07/13 audio watermarking discrete cosine transform (DCT) discrete wavelet transform (DWT) synchronization