北京大学学报(自然科学版)
北京大學學報(自然科學版)
북경대학학보(자연과학판)
ACTA SCIENTIARUM NATURALIUM UNIVERSITATIS PEKINENSIS
2006年
3期
366-370
,共5页
谢华%Harald MICHALIK%金声震%艾国祥
謝華%Harald MICHALIK%金聲震%艾國祥
사화%Harald MICHALIK%금성진%애국상
天文%图像压缩%信噪比%率控制%并行
天文%圖像壓縮%信譟比%率控製%併行
천문%도상압축%신조비%솔공제%병행
astronomy%image compression%SNR%rate control%parallel
对JPEG2000算法提出了一种新的改进,以提高它的编码效率.通过修改编码顺序,使得在每个Tile中,数据按照其重要性降序编码.从而,码流截断方法也随之简化,并可以提前终止编码,而率失真效果仍接近最优.最后,给出一个可行的并行化方案,可大大缩短运行时间.改进后的JPEG2000更适用于计算资源有限的星上系统,满足了空间太阳望远镜的压缩需求.
對JPEG2000算法提齣瞭一種新的改進,以提高它的編碼效率.通過脩改編碼順序,使得在每箇Tile中,數據按照其重要性降序編碼.從而,碼流截斷方法也隨之簡化,併可以提前終止編碼,而率失真效果仍接近最優.最後,給齣一箇可行的併行化方案,可大大縮短運行時間.改進後的JPEG2000更適用于計算資源有限的星上繫統,滿足瞭空間太暘望遠鏡的壓縮需求.
대JPEG2000산법제출료일충신적개진,이제고타적편마효솔.통과수개편마순서,사득재매개Tile중,수거안조기중요성강서편마.종이,마류절단방법야수지간화,병가이제전종지편마,이솔실진효과잉접근최우.최후,급출일개가행적병행화방안,가대대축단운행시간.개진후적JPEG2000경괄용우계산자원유한적성상계통,만족료공간태양망원경적압축수구.
A new coding and rate control method for JPEG2000 is proposed to improve its coding efficiency. Through modifying the coding order, the most important passes are coded first in a whole tile. Then, a simple data-stream truncation method is able to both terminate the coding in advance and approximate the optimal rate distortion. At the end, a feasible parallel implementation is proposed and it is to speed up JPEG2000 significantly. The improved algorithm makes JPEG2000 much more beneficial to applications with the restricted computing resource on board. The research satisfies the elementary requirements of image compression of Space Solar Telescope.