国防科技大学学报2009，Vol.31Issue(5)：54-57,4.
基于快速方向重叠变换的图像压缩
Fast Directional Lapped Transform Based Image Compression
摘要
Abstract
Traditional discrete cosine transform (DCT) can only sparsely represent the horizontal and vertical edges in images, and the computation complexity of directional prediction DCT (DPDCr), which is of ability to represent more directions, is much higher. To overcome these shortcomings, the fast directional lapped transforms (FDLT) is proposed, in which the transform is performed on the predefined direction mode and the energy in edges lying across blocks is compacted further. In Comparison with DPDCr, FDLT needs no interpolation. So FDLT can sparsely represent the anisotropic edges in images much faster. Furthermore, special lifting algorithm is designed to ensure the perfect reconstruction. The computation of FDLT is no more than 2 times of DCT's. Coding with the same set partition method, PSNR of images compressed with FDLT is 0.5dB higher than that with Dcr. FDLT based compression also achieves clearer edges and details in the reconstructed images.关键词
图像压缩/方向变换/离散余弦变换/重叠变换Key words
image compression/directional transform/discrete cosine transform(DCT) /lapped transform分类
信息技术与安全科学引用本文复制引用
陈波,成礼智,王红霞..基于快速方向重叠变换的图像压缩[J].国防科技大学学报,2009,31(5):54-57,4.基金项目
国家自然科学基金资助项目(10601068),国防科技大学校基金资助项目(0806) （10601068）
