中国科学院机构知识库网格系统: 检索

Orthogonal sparse fractal coding algorithm based on image texture feature 期刊论文 OAI收割
IET IMAGE PROCESSING, 2019, 卷号: 13, 期号: 11, 页码: 1872-1879
作者: Cao, Jian; Zhang, Aihua; Shi, Lei

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收藏 | 浏览/下载：224/0 | 提交时间：2019/10/11

image coding feature extraction fractals data compression image texture image reconstruction orthogonal codes image colour analysis transforms decomposition matrix algebra orthogonal sparse grey level sparse decomposition decoding speed orthogonal sparse fractal coding algorithm image reconstruction quality image texture feature extraction fractal image compression coding algorithm grey description feature extraction orthogonal sparse grey level transform

知识引导的汉语语音识别搜索算法研究 学位论文 OAI收割
工学博士, 中国科学院自动化研究所: 中国科学院研究生院, 2012
作者: 杨占磊

收藏 | 浏览/下载：100/0 | 提交时间：2015/09/02

语音识别解码算法路径扩展概率融合 Speech recognition decoding algorithm path extension probability fusion

Design and image restoration research of a cubic-phase-plate system (EI CONFERENCE) 会议论文 OAI收割
5th International Symposium on Advanced Optical Manufacturing and Testing Technologies: Advanced Optical Manufacturing Technologies, April 26, 2010 - April 29, 2010, Dalian, China
作者: Zhang J.; Zhang J.; Zhang J.; Shi G.; Zhang X.

收藏 | 浏览/下载：25/0 | 提交时间：2013/03/25

Wave-front coding technology is a novel jointly optical and digital imaging technology which can greatly extend the depth of focus of optical systems. The image restoration process is an important part of wave-front coding technology. Using wave-front coding makes the modulation transfer function(MTF) values of the optical systems change little over a range of several times the depth of focus which means the system MTF is quite insensitive to defocus and there is no zero in the passband. So we can design a single filter for the restoration of images in different defocus positions. However it's hard to avoid noise during image acquisition and transmission processes. These noises will be amplified in the image restoration especially in the high frequency part when the MTF drop is relatively low. The restoration process significantly reduces the system signal to noise ratio this way. Aimed at the problem of noise amplification a new algorithm was proposed which incorporated wavelet denoising into the iterative steps of Lucy-Richardson algorithm. Better restoration results were obtained through the new algorithm effectively solving the noise amplification problem of original LR algorithm. Two sets of identical triplet imaging systems were designed in one of which the cubic-phase-plate was added. Imaging experiments of the manufactured systems were carried and the images of a traditional system and a wave-front coded system before and after decoding were compared. The results show that the designed wave-front coded system can extend the depth of focus by 40 times compared with the traditional system while maintaining the light flux and the image plane resolution. 2010 Copyright SPIE - The International Society for Optical Engineering.

A design of high-speed and low-consume parallel grouping RS code and simulation (EI CONFERENCE) 会议论文 OAI收割
2010 3rd International Conference on Advanced Computer Theory and Engineering, ICACTE 2010, August 20, 2010 - August 22, 2010, Chengdu, China
Chen C.; Jin G.

收藏 | 浏览/下载：24/0 | 提交时间：2013/03/25

RS code is a linear error correction codes with better error correction capability is widely used in different kinds of occasions for communications or data storage. But for its high difficulty of coding and decoding algorithm and low throughput optimization RS algorithm is always studied as one of the focus in the error-correction field. A new coding method parallel coding and decoding data into groups in lower step finite field for avoiding complex matrix iteration and Chien search computation is proposed in this paper. It is proved that the coding and decoding throughput of the parallel grouping RS coder is increased and the hardware complexity is reduced with changeless error-correction capability from the simulation results using ModelSim SE 6.0 and synthetic results using ISE 9.11. 2010 IEEE.

An open system design of high speed image transmission (EI CONFERENCE) 会议论文 OAI收割
1st International Symposium on Computer Network and Multimedia Technology, CNMT 2009, December 18, 2009 - December 20, 2009, Wuhan, China
作者: Li S.

收藏 | 浏览/下载：21/0 | 提交时间：2013/03/25

A high speed image transmission system is designed to compress the aerial image improve the speed of image transmission. This paper introduces how PTP (Picture Transfer Protocol) can be extended to work over generic USB interfaces the multi-threaded transfer mode of file stream and the JPEG decoding algorithm self-developed an open system of aerial digital camera image transmission. Experiments show that image transmission with PTP not only guarantees a good image quality and prevents data loss but also fulfill the requirement of aerial camera large image transmission that ensure the advantage of high frame rate. 2009 IEEE.

知识引导的段模型解码及其关键词检测研究 学位论文 OAI收割
工学博士, 中国科学院自动化研究所: 中国科学院研究生院, 2008
作者: 张华

收藏 | 浏览/下载：34/0 | 提交时间：2015/09/02

语音识别随机段模型关键词检测快速解码算法 speech recognition segment model keyword spotting fast decoding algorithm

On the list and bounded distance decodability of Reed-Solomon codes 期刊论文 OAI收割
SIAM JOURNAL ON COMPUTING, 2007, 卷号: 37, 期号: 1, 页码: 195-209
作者: Cheng, Qi; Wan, Daqing

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收藏 | 浏览/下载：19/0 | 提交时间：2018/07/30

list decoding algorithm bounded distance decoding algorithm Reed-Solomon codes discrete logarithm problem

基于随机段模型的汉语语音识别算法研究 学位论文 OAI收割
工学博士, 中国科学院自动化研究所: 中国科学院研究生院, 2006
作者: 唐赟

收藏 | 浏览/下载：44/0 | 提交时间：2015/09/02

段模型随机段模型汉语数字串识别大词汇量连续语音识别快速搜索算法段模型建模 Segment Model Stochastic Segment Model Mandarin digit string recognition LVCSR fast decoding algorithm segment-based modeling

Compression of remote sensing image based on Listless Zerotree Coding and DPCM (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
Chen S.-L.; Huang L.-Q.

收藏 | 浏览/下载：32/0 | 提交时间：2013/03/25

The data quantity of remote sensing image is very large. Furthermore the lowest frequency subband contains the main energy of original image and reflects the coarse of original image after remote sensing image is transformed by wavelet so it is very important to the reconstructed image. Therefore a hybrid image compression method based on Listless Zerotree Coding (LZC) and DPCM is presented namely the lowest frequency subband is compressed by DPCM and others are compressed by LZC. LZC is a kind of zerotree coding algorithm for hardware implementation which is based on SPIHT and substitutes two significant bit maps for three lists in SPIHT algorithm. Thereby LZC significantly reduces the memory requirement and complexity during encoding and decoding procedure. But LZC doesn't recognize the significance of grandchild sets so the PSNR values of LZC are lower than SPIHT's and the compression speed drops. It is improved by adding a significant bit map that recognizes the significance of grandchild sets. A comparison reveals that the PSNR results of the hybrid compression method are 2 dB higher than those of LZC and the compression speed is also improved.

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：42/0 | 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.