车载通信系统中JPEG压缩算法的量化表改进

Improvement of Quantization Table of JPEG in Vehicle-carried Communication System

摘要:

为使车载通信平台中图像数据实时传输,需要对图像进行压缩；图像压缩算法的设计需要综合考虑压缩比、图像质量及处理时间等因素；文章在研究JPEG压缩标准的基础上,针对车载通信系统硬件平台限制及系统对图像质量的要求,设计了一种量化表构造算法,对JPEG标准推荐量化表进行改进；采用改进后的量化表对原始图像进行压缩,压缩图像在满足系统中DM642片上EDMA一次传输能力限制的条件下,峰值信噪比显著提高,满足车载通信系统要求。

Abstract:

In vehicle-carried communication system, in order to transmit the image in real time, compression is needed. Image quality, compression ratio and processing time should be considered while designing the image compression algorithm . Based on thorough study of JPEG, taking consideration of the hardware limitation of vehicle-carried communication system and its requirement of the quality of the images, this paper designs an algorithm to construct a new quant table. When compress the original image with the new quantization table, the compressed image meets the limitation of transmission capacity of the EDMA in DM642, and the peak signal-to-noise ratio of the compressed image is significantly improved, and satisfies the requirement of vehicle-carried communication system.