摘要
分析了信源信道编码速率对图像质量的影响,提出一种联合信源信道编码的速率分配方案.针对渐进图像的速率分配问题建立了数学模型,对模型的求解进行了简化,并采用拉格朗日乘数法,在满足一定的约束条件下实现了速率的最优化分配.在瑞利及Gilbert Elliot信道下的仿真结果表明,该方案在低信噪比时的性能明显优于固定信道方法,在高信噪比时也较固定信道速率方法有0 2dB左右的性能增益.
The influence of the source and channel coding rate on image quality is analyzed, and a rate allocation scheme for joint source channel coding of the progressive image over a wireless channel is proposed. In the scheme, a math model for the rate allocation of the progressive image is established, the solution of which is simplified, with the optimum allocation of the rate being realized by the Lagrange multipliers method on the condition that a certain constraint is satisfied. Simulations in the Rayleigh and GilbertElliot channel show that the scheme can obviously improve the performance when the SNR is low and offer a gain of about 02?dB when the SNR is high compared with the fix rate allocation scheme.
出处
《西安电子科技大学学报》
EI
CAS
CSCD
北大核心
2002年第6期716-720,共5页
Journal of Xidian University
基金
国家自然科学基金资助项目(60002007)
关键词
无线信道图像
联合信源信道编码
速率分配
SPIHT
卷积码
通信
joint source channel coding
rate allocation
set partitioning in hierarchical trees
rate-compatible puncture convolutional code
