基于改进提升小波变换SPIHT的图像压缩算法

A Lossy Image Coding for Wireless Multimedia Sensor Networks

摘要:

通过对提升小波变换的SPIHT算法进行改进和优化,提出了一种适用于无线多媒体传感器网络(WMSNs)的简单、高效、节能的有损图像压缩算法；该算法采用只包含加法和移位操作的整数小波提升算法,使得小波分解的计算量减半,大大提高了变换速度；采用量化截断的预处理技术,省去大量不重要高频系数的量化编码,解决了提升变换后SPIHT算法编码效率低的问题；去除了最外层高频系数的分解和编码,有效地减少了变换和编码的能耗；理论分析和仿真结果均表明,在保证一定重建图像质量的前提下,该算法大大降低了图像压缩能耗,提高了算法的压缩效率和执行效率,非常适合于资源受限的WMSNs中的图像压缩。

Abstract:

Through improving and optimizing the lifting wavelet transform SPIHT algorithm, a simple, high-efficient and energy saving image coding scheme for wireless multimedia sensor networks is proposed. The algorithm uses integer wavelet contains only addition and shift operations to enhance the algorithm, making calculation of wavelet decomposition halved; the conversion rate is improved greatly. Use of quantitative truncated pretreatment technology, A large number of quantization coding of unimportant high frequency coefficients are eliminated, problem of low efficiency of SPIHT coding after lifting transform is solved, Decomposition and encoding of the outermost high-frequency coefficients are omitted, energy of transform and coding is reduced effectively. Theoretical analysis and simulation results show that, under the guaranteed quality of the reconstructed image, the algorithm reduces the energy consumption of image compression greatly, Compression efficiency and execution efficiency of the algorithm are improved, which is suited for image compression in resource-constrained WMSNs ideally.