Improved Adaptive Huffman Coding for Ultrasonic Non-destructive Testing Data

With the increasing demand for higher accuracy in non-destructive testing, technologies such as multi-probe detection and dense sampling have been widely adopted. These methodologies generate substantial quantities of data, which in trun leads to challenges concerning data transmission efficiency and storage space. To address these issues, this paper proposes a fast adaptive Huffman coding method with a threshold. It reduces the redundant information of ultrasonic signals at adjacent sampling points, establishes a threshold for character occurrence, and adopts a local update strategy for the coding table. Comparative experiments demonstrate that this method outperforms Deflate coding, LZW coding, and traditional adaptive Huffman coding when dealing with non-smooth data distributions. Additionally, the compression speed is improved by 100% compared to the previous methods.