基于非线性提升小波的有损图像压缩及其优化

Optimization of Image Lossy Compression Based on Nonlinear Lifting Wavelet Transform

基于提升的小波变换结构简单,不需要额外的存储空间,易于实现,在图像压缩中具有很好的应用价值。文章对使用非线性算子(如最大值,最小值等)构造的非线性提升小波结合SPIHT编码算法在图像有损压缩方面的性能进行了分析。同时,提出了一种改进的非线性提升小波实现结构。实验表明,该实现结构应用在图像有损压缩时,恢复图像的峰值信噪比和主观视觉效果均有明显提高。

Lifting wavelet transform has a simple structure,needs no more storage space and is very easy to be imple-mented,which is suitable for image compression.This paper tests the performance of a family of nonlinear lifting wavelet(such as max-lifting and min-lifting)with SPIHT codec.Meanwhile,it improves the structure of the nonlinear wavelet transform.The simulation shows that this improved structure can remarkably increase PNSR and visual effects of the image when it is implied on lossy compression.