摘要
电磁超声是管道裂纹检测的有效手段,由于原始波形的数据量很大,而检测器存储设备的容量和存储速度相对有限,有必要研究检测数据在线压缩算法。文中分析了管道检测的特殊环境及其对数据压缩的要求,针对检测器系统的特点及检测数据的特征,提出了分段自适应压缩算法。该算法能够根据信号的幅值变化实时改变压缩比,并且可以通过改变压缩阈值的方法来调整压缩的精度。实验结果显示:该算法应用在电磁超声导波波形数据上,有着较为理想的波形保真度,同时达到了较高的压缩比。对算法优缺点的分析和对压缩质量的评估结果表明:分段自适应压缩算法在压缩效率,压缩质量和算法复杂度等多方面均满足管道电磁超声检测大量数据压缩的要求。
The electromagnetic acoustic transducer（EMAT） is an effective method in pipeline crack-inspection.Because of massive amount of original waveform data and limited speed and capacity of storing device,analysis of online inspection data compression algorithms is needed.This paper analyzes the special environment of pipeline inspection and requirements to data compression.A subsection adaptive compression algorithm was developed based on the inspection system characteristics and the inspection data features.The algorithm can alter its compression ratio along with the amplitude change of the original signal with the compression precision being able to be adjusted by altering the compression threshold.Experimental results indicate that in the application of EMAT guide-wave data compression,the algorithm has ideal fidelity,and can achieve high compression ratio at the same time.The analysis of advantages and disadvantages of the algorithm and the assessment of the compression quality show that the subsection adaptive compression algorithm satisfies the requirements of the pipeline EMAT inspection data compression in the aspects of the compression efficiency,compression quality and arithmetic complexity.
出处
《清华大学学报（自然科学版）》
EI
CAS
CSCD
北大核心
2010年第10期1619-1622,共4页
Journal of Tsinghua University(Science and Technology)
基金
国家"八六三"高技术项目(2007AA06Z223)
关键词
数据压缩
电磁超声
管道检测
峰值信噪比
data compression
electromagnetic acoustic transducer（EMAT）
pipeline inspection
peak signal to noise ratio
