Fast motion estimation of one-dimensional laser speckle image and its application on real-time audio signal acquisition

Abstract

Vibration measurement using laser speckle image, which can precisely detect object vibration without contacting target object, is an appealing topic. However, due to the limitation of image processing speed, previous researches on this topic have not achieved high-speed real-time detection and regeneration of audio signal. In this manuscript, we detect object vibration using one-dimensional laser speckle image. A fast and sub-pixel accuracy algorithm has been proposed to estimate the displacement of captured one-dimensional laser speckle images. Experiment results show that the proposed system can achieve 20kHz rea-time sampling rate, and the high frequency audio signal can be restored with high quality in real time.