【摘要】 为解决10KV架空线路对地电场值海量存储问题,提出一种基于二维小波提升-DCT变换对地电场值压缩算法。将一维对地电场采样值按128×128方阵构成数据块。采用haar小波提升,对该数据块做一层小波分解,得到4个64×64数据块;用二维DCT矩阵对每个64×64数据块变换处理,利用筛选矩阵对DCT系数和小波系数进行筛选;对筛选系数进行一维小波变换编码,完成数据压缩。合理构造筛选系数,可以达到1024∶1高压缩比数据压缩效果。扩大原始数据块大小,压缩比可以达到更高。将其仿真结果与其它算法进行比较,验证了该算法数据压缩的有效性。更多还原

【Abstract】 To solve the problem of massive storage of ground-electric field data sampled from 10 KV overhead lines,a compression algorithm of ground electric field value based on two-dimensional lifting wavelet-discrete cosine transform was proposed.One-dimensional sampled data of electric field were composed into data blocks by 128×128 matrixes.Every data block was decomposed into one layer wavelet coefficients by using haar wavelet lifting,and four 64×64 data blocks were obtained.The two-dimensional discrete cosine transform was used to transform each 64×64 data block.DCT coefficients and wavelet coefficients were screened using screening matrix.The reserved coefficients were coded through one-dimensional wavelet transform and data compression was completed.While the screening coefficients are reasonably constructed,the high compression ratio of sampled data achieves 1024∶1.The compression ratio can be higher by enlarging the size of the original data block.The results of simulation,which are compared to other well-known algorithms,indicate that the proposed algorithm is excellent for data compression.更多还原