中国科学院机构知识库网格
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适合DSP处理的低内存并行SPIHT算法 期刊论文  OAI收割
光学技术, 2006, 期号: 4
陈升来; 黄廉卿
收藏  |  浏览/下载:12/0  |  提交时间:2012/09/25
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.  
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:30/0  |  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.