针对基于压缩感知的图像编码系统,分析了系统中编码参数和码率以及失真的关系,在此基础上提出了基于压缩感知的图像编码系统的码率-失真模型。根据所提模型设计了率失真优化的压缩感知图像编码算法。在给定码率的条件下,优化编码参数,使得编码器失真最小。算法在Matlab的编码平台上进行了仿真和实验,结果证明提出的码率-失真模型能够很好地拟合实际率失真曲线,并且基于该模型的率失真优化算法有效的提高了压缩感知图像编码系统的性能。
In view of compressive sensing based image coding schemes, the relationship of rate and coding parameters and relationship of distortion and coding parameters are analyzed. Moreover, a source rate and distortion model is proposed. Based on the R-D model, the optimal number of measurements and quantization step size are determined according to the rate-distortion criteria. The proposed algorithm is implemented on the platform of Matlab. The accuracy of the proposed R-D model is verified through experiments. Experimental results show that the proposed algorithm improves coding performances substantially.