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	Efficient rate control technique for CCSDS image encoding (EI CONFERENCE) 会议论文 OAI收割 IEEE 2nd International Conference on Computing, Control and Industrial Engineering, CCIE 2011, August 20, 2011 - August 21, 2011, Wuhan, China Jin L. 收藏 \| 浏览/下载：93/0 \| 提交时间：2013/03/25 For the limitation of data transmission bandwidth and real time transmission demand generally image compression is required to implement the precise and flexible rate control algorithm. Rate control is an important issue in the image compression field. This paper considers the problem of rate allocation to each encoded segment for CCSDS image compression. One straightforward method is to allocate an equal amount of rate to each segment based on the average of the total number of compressed bytes. The obvious drawback of this method is that different segment will be reconstructed to different quality so the overall quality of the reconstructed image will not be optimized. For the shortage of the original rate control method as to improve the overall quality of the reconstructed image an improved rate control algorithm is proposed for CCSDS image encoding. The key component of the proposed rate control method is the appropriate rate allocation. Experiments on the test images show that the PSNR can be increased at about 0.3dB on average compared to the original algorithm. Therefore experimental results confirm the effectiveness of the proposed algorithm in terms of objective evaluation and the rate-distortion performance of the reconstructed image is improved. 2011 IEEE.
	Color videos' multichannel combination for bandwidth reduction and fast frequency domain processing (EI CONFERENCE) 会议论文 OAI收割 2nd International Workshop on Education Technology and Computer Science, ETCS 2010, March 6, 2010 - March 7, 2010, Wuhan, Hubei, China 作者: Li S. 收藏 \| 浏览/下载：16/0 \| 提交时间：2013/03/25 The real color video consumes much transfer bandwidth and the resource of the hardware. A new approach is introduced to process the real color video images in real-time using color components combination to fit to the limited transmission bandwidth. The Y U V planes of video images are packed to construct a 2 dimensional complex array. Through the decomposition of frequency domain the Y U V frequency can be got respectively by performing Fourier transform a time on the specific complex array. These frequencies can be filtered to generate the final filtered images. The experiment results show that the proposed algorithm is 3X speed compared to the traditional algorithm and it reduces 1/3 bandwidth of video data stream. 2010 IEEE.
	A high-speed acquisition and processing system of the laser speckle signal on the magnetic fluid (EI CONFERENCE) 会议论文 OAI收割 International Symposium on Photoelectronic Detection and Imaging 2009: Laser Sensing and Imaging, June 17, 2009 - June 19, 2009, Beijing, China 作者: Sun Y.; Sun Y.; Wan Q.-H. 收藏 \| 浏览/下载：27/0 \| 提交时间：2013/03/25 In order to achieve the dynamical detection and real-time analysis of the movement status of the magnetic fluid according to the difficulties of the detection of the magnetic fluid established a high-speed acquisition and processing system of laser speckle signal on the magnetic fluid. First of all the FPGA (EP2C8T144C8N) drived the linear array CCD(TCD1501D) to scan in the corresponding time sequence given by the computer collected the laser speckle interferometric image in rapid change on the surface of the magnetic fluid which followed the movement of the magnetic fluid and the signal collected by CCD was converted into the digital data through the high-speed A/D convertor and stored into the internal buffer FIFO of the FPGA whose width and depth were designed by the user as required. Then the FPGA sent the digital signal of the laser speckle interferometric images into the computer through the USB2.0 highspeed differential bus whose transmission rate can reach 480Mb/s in theory. Finally the distribution of the laser speckle on the magnetic fluid was messy and random which carried certain information about the surface of the magnetic fluid based on the theories of the statistic correlation and the subdivision of images analysing and processing the laser speckle interferometric images indirectly got the movement status of the magnetic fluid under the electromagnetic field. The experimental results show that: the High Speed Acquisition and Processing System has the advantage of full-court non-contact non-invasive high-precision and high reliability and so on. The detection resolution of high speed acquisition and processing system is superior to 1m and the sample rate is 3Msps which basically meets the requirements of the magnetic fluid movement state detection. 2009 SPIE.
	The compression and storage method of the same kind of medical images-DPCM (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：13/0 \| 提交时间：2013/03/25 Medical imaging has started to take advantage of digital technology opening the way for advanced medical imaging and teleradiology. Medical images however require large amounts of memory. At over 1 million bytes per image a typical hospital needs a staggering amount of memory storage (over one trillion bytes per year) and transmitting an image over a network (even the promised superhighway) could take minutes - too slow for interactive teleradiology. This calls for image compression to reduce significantly the amount of data needed to represent an image. Several compression techniques with different compression ratio have been developed. However the lossless techniques which allow for perfect reconstruction of the original images yield modest compression ratio while the techniques that yield higher compression ratio are lossy that is the original image is reconstructed only approximately Medical imaging poses the great challenge of having compression algorithms that are lossless (for diagnostic and legal reasons) and yet have high compression ratio for reduced storage and transmission time. To meet this challenge we are developing and studying some compression schemes which are either strictly lossless or diagnostically lossless taking advantage of the peculiarities of medical images and of the medical practice. In order to increase the Signal to-Noise Ratio (SNR) by exploitation of correlations within the source signal a method of combining differential pulse code modulation (DPCM) is presented.
	Study on CCD image compression and mass storage (EI CONFERENCE) 会议论文 OAI收割 ICO20: Optical Information Processing, August 21, 2005 - August 26, 2005, Changchun, China 作者: Liu H.; Liu H.; Liu H. 收藏 \| 浏览/下载：28/0 \| 提交时间：2013/03/25 When CCD camera photographs massive images in the air it is very important to compress and save CCD image timely and validly. This paper designs the CCD image compression and mass storage system. The one part is image compression: this paper introduces a reduced memory still image compression algorithm based on Listless Zerotree Coding (LZC). Compared with SPIHT the approach significantly reduced memory requirement and no reducing the quality of the reconstructed image. The other part is image mass storage: this system uses a kind of special hard disk storage devices that can realize faster data transmission to SCSI (Small Computer System Interface) devices even if it separates oneself from PCs. In the faster data acquisition and storage system data storage is a key technology. Normal approach is saving the data to mass memories and then processing and saving the data after complete acquisition. The continuous acquisition time is restricted with the storage capacity in the normal method so that it can't receive the requirement of CCD image storage on many occasions. While its price will be geminate increasing when we increase the storage capacity. So the approach in this paper is better one to use fast disks on data direct mass storage considering the storage capacity read/write speed and unit cost. The result of the experiment shows that the system has compressed and saved CCD image validly so it reached the anticipative purpose.
	The develop of 622Mbits/s free space laser communication system 会议论文 OAI收割 conference on optoelectronic devices and integration, beijing, peoples r china, nov 08-11, 2004 Zhou, Y; Xie, FZ; Yan, XJ; Fan, ST; Zuo, F 收藏 \| 浏览/下载：153/23 \| 提交时间：2010/03/29 free space laser communication system optical antenna semiconductor laser receive circuit laser driver circuit transmission of data and images