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	Design of high speed and parallel compression system used in the big area CCD of high frame frequency (EI CONFERENCE) 会议论文 OAI收割 2011 International Conference on Precision Engineering and Non-Traditional Machining, PENTM 2011, December 9, 2011 - December 11, 2011, Xi'an, China 作者: Li G.-N.; Jin L.-X.; Zhang R.-F.; Wang W.-H.; Li G.-N. 收藏 \| 浏览/下载：51/0 \| 提交时间：2013/03/25 According to the area CCD camera of characteristics such as high resolution capacity and high frame frequency this paper puts forward a high speed and parallel image compression system of high integration degree. Firstly according to the work principle of the area CCD FPGA is adopted to realize the timing driving and multichannel and parallel analog signal handling to raise the export frame frequency of the area CCD. Secondly with an image compression scheme based on FPGA embedded processor MicroBlaze and ADV212 compression chip real time image compression and the high speed area CCD are realized. Finally by detecting the analog signal of the area CCD output the real time compression of the big area CCD image is carried out in different compression ratios and the compression performance is analyzed. Experiment result shows that this scheme can realize real time image compression with the biggest data rate of 520Mbps. When compression bit ratio is 0.15 the signal-to-noise ratio of peak value can reach 36 dB. Image collection and image compression are integrated which reduces the data transmission between them and improves systematic integration degree.
	侧面抽运国产Nd∶YAG陶瓷棒的激光特性期刊论文 OAI收割中国激光, 2008, 卷号: 35, 期号: 12, 页码: 2001, 2004 唐昊; 朱小磊; 姜本学; 潘裕柏收藏 \| 浏览/下载：1522/238 \| 提交时间：2009/09/18 激光器 Atomic percents Nd:YAG陶瓷 Average powers 激光二极管阵列 Beam divergence angles 侧面抽运 Laser diode array 被动调Q Nd:YAG ceramic Nd:yag ceramic lasers Output couplers Output performances Passively Q-switched Pulse widths Side pump Slope efficiencies Transmission ratios Wave outputs Working frequencies Yag crystals
	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：41/0 \| 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.