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	Efficient coding matters in the organization of the early visual system 期刊论文 OAI收割 NEURAL NETWORKS, 2018, 卷号: 105, 页码: 218-226 作者: Kong, Qingqun; Han, Jiuqi; Zeng, Yi; Xu, Bo \| 收藏 \| 浏览/下载：33/0 \| 提交时间：2018/10/10 Early Visual Stages Hierarchical Structure Efficient Coding Brain-inspired Neural Networks
	Image compression based on contourlet and no lists SPIHT (EI CONFERENCE) 会议论文 OAI收割 2010 International Conference on Computer, Mechatronics, Control and Electronic Engineering, CMCE 2010, August 24, 2010 - August 26, 2010, Changchun, China 作者: Zhang S. 收藏 \| 浏览/下载：37/0 \| 提交时间：2013/03/25 The volume of raw image data captured by the high resolution camera is extremely huge. Thus the efficient image compression method should be used to decrease the bit rate. The image compression method based on wavelet is used more widely nowadays. However two dimensional wavelet is only the tensor product of the one dimensional wavelet whose support region of basis function is extended from interval to square. Contourlet is an image multiscale geometric analysis tool which could represent image sparsely and has strong capability of nonlinear approximation. The basis function of contourlet is multidirectional and anisotropic. Nevertheless contourlet is redundant. So the non-redundant Wavelet Based Contourlet Transform (WBCT) is used in this paper. The SPIHT algorithm is very efficient way to coding the significant coefficients. And the improved no lists SPIHT is more easy to implemented by hardware. Image compression method based on the combination of both wavelet based contourlet transform and no lists SPIHT coding is proposed in the paper. Experiment shows that compared to wavelet based scheme the contourlet scheme can reserve the texture of the image. For barbara test image when coding at low bit rate the PSNR can improve about 0.2dB. 2010 IEEE.
	SoC test data compression technique based on RLE-G (EI CONFERENCE) 会议论文 OAI收割 2010 International Conference on Advanced Measurement and Test, AMT 2010, May 15, 2010 - May 16, 2010, Sanya, China 作者: Liu W.; Yang L.; Yang L.; Zheng X. 收藏 \| 浏览/下载：20/0 \| 提交时间：2013/03/25 Test data compression has been an effective way to reduce test data volume and test time as well as to solve automatic test equipment (ATE) memory and bandwidth limitation. We analyze the limitations of current test data compression algorithm and draw on the previous experience to deduce an optimal compression coding model suitable for SoC test data. In addition in this paper we make full use of the relevance of the test vectors and the advantages of statistical coding to present an efficient test data compression method RLE-G based on the coding model and give the RLE-G the optimal compression efficiency of the boundary conditions and realization steps. The experimental results for ISCAS 89 benchmark circuits demonstrate RLE-G have the excellent advantages of high compression ratio. (2010) Trans Tech Publications.
	Wavelet-based contourlet coding using SPECK algorithm (EI CONFERENCE) 会议论文 OAI收割 2008 9th International Conference on Signal Processing, ICSP 2008, October 26, 2008 - October 29, 2008, Beijing, China Xiu-Wei T.; Xi-Feng Z.; Tie-Fu D. 收藏 \| 浏览/下载：41/0 \| 提交时间：2013/03/25 We proposed a new still image compression algorithm called CSPECK witch was constructed by the wavelet-based contourlet transform (WBCT) and set partitioning embedded block coding (SPECK). In the WBCT the high frequency sub-band decomposed by the wavelet transform was further decomposed into multiple directional sub-bands by directional filter bank so as to explain the edge and texture of the image more sparsely. The SPECK algorithm exhibits lower complexity and more efficient compression ratio than SPIHT based on WBCT. Experimental results demonstrate that the proposed method is efficient in coding images that possess mostly textures and contours. The simulation results also show that this new coding algorithm increases the PSNR over CSPIHT. 2008 IEEE.
	High speed, low memory image coding using zero blocks of wavelet coefficients (EI CONFERENCE) 会议论文 OAI收割 4th International Conference on Image and Graphics, ICIG 2007, August 22, 2007 - August 24, 2007, Chengdu, China 作者: Zhang T.; Yang W.-G. 收藏 \| 浏览/下载：21/0 \| 提交时间：2013/03/25 We propose a new high speed low memory SPECK image coder based on the form of block-unit states called LBUS-SPECK which uses the form of block-unit states and the form of block exponents to substitute LIS and LSP of SPECK. A form of block-unit states is introduced to store the significance flag of coefficients and the value of the block-unit exponents. A form of block exponents is introduced to store the block exponents which are used to represent the max coefficient in a decomposed block. A new block depth-finding strategy is developed for searching insignificant sets at sorting stage. Experimental results show that the obtained PSNR values for the decoded images are very close to those of SPECK algorithm and the memory consumption is reduced by 9 times the encoding timing is saved about 15%. Comparing with SPECK algorithm this algorithm not only has better performance of the decoded images but also is easy to implement especially it provides an efficient way for hardware implementation of wavelet embedded block coding. 2007 IEEE.
	Lossless wavelet compression on medical image (EI CONFERENCE) 会议论文 OAI收割 4th International Conference on Photonics and Imaging in Biology and Medicine, September 3, 2005 - September 6, 2005, Tianjin, China 作者: Liu H.; Liu H.; Liu H. 收藏 \| 浏览/下载：27/0 \| 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.
	Image compression based on biorthogonal wavelet transform (EI CONFERENCE) 会议论文 OAI收割 ISCIT 2005 - International Symposium on Communications and Information Technologies 2005, October 12, 2005 - October 14, 2005, Beijing, China 作者: Gao Y.; Liu H.; Liu H.; Liu H. 收藏 \| 浏览/下载：23/0 \| 提交时间：2013/03/25 A method for image compression of biorthogonal wavelet transform based on lifting scheme with SPIHT (Set Partitioning In Hierachical Trees) is proposed in this paper. Wavelet transform affords wide space for image coding algorithms because of its excellent space-frequency localization characterizations. The compact supported symmetrical and biorthogonal wavelet has linear phase so it is applied on image compression area widely. The lifting scheme is an efficient method for constructing the wavelet filter after multiresolution. Under the condition of biorthogonal biorthogonal wavelet base can be constructed freely according to the wavelet performance. And it can quicken the implementation speed of the wavelet transform. Analyzing the algorithm of lifting scheme is applying for constructing biorthogonal wavelet. Experimental results indicate that the method of the biorthogonal wavelet that has good performances with SPIHT is applying for image compression so as image synthesis performs well. 2005 IEEE.