Ultrasonic NDE image compression by transform and subband coding

摘要

In this paper, two categories of transform coding and subband coding are comparatively studied for compressing ultrasonic NDE images. The data compression performance of the discrete cosine transform-, the Karhunen-Loeve transform-, and the discrete wavelet transform-based codecs are examined by being applied to ultrasonic NDE images. The effects of these compression methods on the analysis of ultrasonic information in compressed ultrasonic images are examined. Moreover, evaluation of the main elements in image coding system is performed to explore the important factors, which are worth paying more attention when developing a special image compression technique for ultrasonic NDE images.