作　　者： ; ; ; ;

机构地区： 西安电子科技大学电子工程学院智能感知与图像理解教育部重点实验室

出　　处： 《红外与毫米波学报》 2009年第4期311-315,共5页

摘　　要： 提出了一种基于提升方向波变换SAR图像的压缩算法.该算法构造了方向波变换的提升方案,通过改进的四叉树分块算法寻找局部最优的变换方向,有效地描述了图像中的方向特征.根据变换系数分布特性构造了多方向各向异性的多级零树结构,提高了编码效率.对多幅SAR图像的压缩实验表明,较之基于小波的SPIHT和JPEG2000等算法,本文方法在性能指标和视觉效果方面均得到了明显提高,尤其在低比特率下,优势更加突出. A novel SAR image compression algorithm was presented by using lifting directionlet transform（LDT）. The lifting directionlet scheme and improved quad-tree segmentation were proposed to obtain the optimal pair of transform directions, which could capture the image features efficiently. To enhance the coder performance, multi-directional anisotropy hierarchical zerotree was designed, which was suitable to the distribution characteristic of LDT coefficients. Experimental results of real SAR images show that the proposed compression algorithm outperforms the wavelet-based SPIHT and JPEG2000 both in terms of evaluation mettle as well as visual quality, especially at the low-bitrate.

关 键 词： 方向波变换 提升方案 图像压缩 多级零树

领　　域： [电子电信] [电子电信]