一种自适应量化DPCM的测井数据压缩方法

Data compression based on adaptive quantizer DPCM for well logging

随着测井技术的发展,大量测井数据需要实时传输,而现有的测井传输系统的速率难以满足要求。由于测井数据存在信息冗余,压缩数据后再传输可以等效提高传输速率。为此,提出了一种改进的可自适应量化调整编码器的差分脉码调制(DPCM)算法。首先通过对测井数据进行分析获取统计信息极值、分析数据的变化趋势,根据这些信息动态的调整编码的码长和编码器的量化步长,保持编码器与方差的统一。实验结果表明改进之后的DPCM可以有效的降低数据的波动性带来的影响,减小数据的编码长度,提高压缩比。

With the fast development of well logging,a large number of data need to be transmitted from downhole to surface devices.However,the existing transmission system of well logging cannot meet the requirements of transmission rate and real time.To solve these problems,an improved DPCM algorithm is proposed,which can adjust the encoder adaptively.Firstly,through the analysis of logging data,the maximum value of statistical information is obtained,and the change trend of data is analyzed.According to this information,the code length and quantization step size of encoder are adjusted dynamically to keep the unity of encoder and variance.The experimental results show that our improved DPCM can effectively reduce the data jitter,reduce the coding length of data,and enhance the maximum compression ratio.