Performance evaluation of 3D compression for ultrasonic nondestructive testing applications

Ultrasonic imaging and nondestructive testing applications require large volumes of data. Therefore, it is essential to compress data for storage and transmission without degrading the signal quality or inadvertently damaging desirable signal features. In this study, the ultrasonic signal compression and signal reconstruction is implemented using discrete wavelet transform (DWT), and direct signal decimation and reconstruction by interpolation when sampling rate exceeds several folds above the Nyquist rate. The objective of this study is to design 1D and 3D compressions and evaluate the degree of compression of ultrasonic data as a function of data integrity. The compression performance is evaluated by calculating the PSNR (peak SNR) and the correlation between the original and reconstructed signals with respect to compression ratio. The performance of the 3D compression algorithm used in this study offers an overall 3D compression ratio of 95% with a PSNR of 27dB indicating high signal fidelity.