Graded compression method for magnetic flux leakage data of pipeline based on compressed sensing

Abstract

The invention provides a graded compression method for magnetic flux leakage data of a pipeline based on compressed sensing, and relates to the field of lossless pipeline detection and signal processing. The method provided by the invention has the following steps of 1, performing pretreatment such as filtering on the magnetic flux leakage data of the pipeline; 2, grading the magnetic flux leakagedata of a pipeline segment to be graded according to the difference of basic grading thresholds; 3, constructing corresponding sparse transform bases for the magnetic flux leakage data with differentgrades; 4, constructing corresponding observation matrixes for the magnetic flux leakage data with different grades and sizes, and performing sparse collection on the magnetic flux leakage data to acquire an observed value; and 5, reconstructing the observed value by using an orthogonal matching pursuit algorithm, to acquire the reconstructed magnetic flux leakage data of the pipeline. Accordingto the method provided by the invention, the technical problems that in the prior art, the compression time is long, the compression proportion is low and the compressed data leakage information is easy to lose are solved, and various kinds of defect information in the magnetic flux leakage data is completely reserved while the condition that the magnetic flux leakage data of the pipeline is maximally compressed is ensured.

Description

technical field [0001] The invention relates to the fields of pipeline non-destructive detection and signal processing, in particular to a pipeline magnetic leakage data compression method based on compressed sensing. Background technique [0002] Submarine pipelines work in a very harsh submarine environment and are vulnerable to corrosion and other complex factors. Once a leak occurs, it will cause very serious consequences. [0003] In the defect detection of submarine pipelines, the distance of one detection is often very long, and the amount of recorded data is particularly large. In order to obtain higher detection accuracy, the number of sensors arranged is also increasing. It is no longer only a single axial or Radial data, but a full range of three-dimensional magnetic flux leakage signal detection for pipelines. Especially for some large-caliber pipelines, the amount of data increases exponentially. However, the space in the pipeline is limited, and the space obt...

AI Technical Summary

Problems solved by technology

[0006] Aiming at the technical problems of long time-consuming, low compression ratio and frequent loss of compressed data defect information in the above-mentioned existing compression methods, the present invention provides a hierarchical compression method for pipeline magnetic leakage data based on compressed sensing. Realize the self-adaptive compression of pipeline magnetic flux leakage data, improve ...

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