基于渐进逆向小波变换方法的压缩同心拼图的实时绘制  

Rendering of 3D Wavelet Compressed Concentric Mosaic Scenery With Progressive Inverse Wavelet Synthesis (PIWS)

作　　者：罗琳[1] 吴韵楠 庄镇泉[1] 李劲[3] 

机构地区：[1]中国科学技术大学电子科学与技术系,安徽合肥230026 [2]普林斯顿大学,普林斯顿新泽西州08544 [3]微软亚洲研究院,北京100080

出　　处：《中国科学技术大学学报》2003年第3期359-368,共10页JUSTC

摘　　要：研究了对小波压缩后的同心拼图数据进行实时解码绘制三维场景的方法 .为了实现压缩场景的实时重建 ,提出了一种渐进逆向小波部分解码方法PIWS .基于上升型小波的渐进式运算特点 ,设计了一种混合的缓存结构 ,通过存储和索引上升运算过程中的中间结果进行计算 ,提供了对三维小波压缩数据的快速随机选择解码 。The concentric mosaics offer a quick solution to the construction and navigation of a virtual environment. To reduce the vast data amount of the concentric mosaics, a compression scheme based on 3D wavelet transform has been proposed in a previous paper. In this work, the efficient implementation of the renderer is investigated. It is preferable not to expand the compressed bitstream as a whole, so that the memory consumption of the renderer can be reduced. Instead, only the data necessary to render the current view are accessed and decoded. The progressive inverse wavelet synthesis (PIWS) algorithm is proposed to provide the random data access and to reduce the calculation for the data access requests to a minimum. A mixed cache is used in PIWS, where the entropy decoded wavelet coefficient, intermediate result of lifting and fully synthesized pixels are all stored at the same memory unit because of the in place calculation property of the lifting implementation. PIWS operates with a finite state machine, where each memory unit is attached with a state to indicate what type of content is currently stored. The computation saving achieved by PIWS is demonstrated with extensive experiment results.Though it's designed for rendering of the compressed concentric mosaic, PIWS can be efficiently extended to other applications with data access to wavelet compressed media as image and video.

关 键 词：小波压缩 上升型 渐进逆向小波变换(PIWS) 同心拼图 选择解码 

分 类 号：TN911.2[电子电信—通信与信息系统]