结合DCT补偿的分形图像编码  

Fractal Image Coding Combined with Discrete Cosine Transform Complement

作　　者：张爱华[1] 常康康[1] 

机构地区：[1]南京邮电大学理学院,江苏南京210023

出　　处：《计算机技术与发展》2014年第1期61-64,68,共5页Computer Technology and Development

基　　金：国家自然科学基金资助项目(61070234);南京邮电大学校科研基金(NY210018)

摘　　要：分形编码是建立在分形迭代函数系统理论基础上的图像压缩方法,压缩比高,但编码时间长,编码过程复杂度高。针对分形压缩方法存在的这些不足,且保证在高压缩比下使得图像质量有明显改善,文中结合离散余弦变换近似的分形图像压缩方法,通过对灰度变换的调节,找到最佳父块及映射,使得均方误差小于容许误差,以此完成编码过程,从而达到提高图像质量和减少编码时间的目的。实验结果表明:文中提出的方法在保证图像质量的前提下,提高了分形编码速度且优于基本分形编码方法。Fractal coding is a new image compression method based on fractal iterated function system. Although the method can achieve high compression, it will take long encoding time and the coding with high computational complexity. In view of these deficiencies for fractal compression method, and ensuring that under the high compression ratio make the image quality is obviously improved, combined with fractal image compression method based on discrete cosine transform approximation, by the regulation of gray-scale transformation, find the best father and mapping, make the mean square error is less than allowable error, to complete the coding process, so as to achieve the purpose of improving image quality and reducing the encoding time. Experimental results show that the presented approach improves the encoding speeds at the premise of guaranteeing the decoding image quality, and is better than the basic fractal coding method.

关 键 词：分形图像编码 峰值信噪比 迭代函数系统 灰度变换 

分 类 号：TP31[自动化与计算机技术—计算机软件与理论]