Embodiments of the present application provide a fault detection method and device based on motion amplification, and relate to the field of fault detection. The fault detection method comprises: acquiring a video
signal and obtaining continuous multiple frames of original image signals containing a fault detection object and corresponding
digital image signals from the video
signal; obtaining full-field vibration displacement information of the fault detection object after image multi-scale analysis; extracting phase information from the full-field vibration displacement information based on a preset amplification multiple and a preset
modal order, replacing local phase information of the corresponding
digital image signals, and obtaining image information of each frame of
digital image signals; and synthesizing each frame of digital image signals with corresponding image information to obtain continuous multiple frames of digital image signals that are motion amplified. The present application performs conversion, analysis, amplification, synthesis and other
processing means on the original image signals after the video
signal is acquired, and obtains motion amplified images in which the fault of a component can be identified by the
naked eye, so that fault detection is convenient and automated.