Color-coded computer-generated Moiré profilometry with real-time 3D measurement and synchronous monitoring video collection

A color-coded computer-generated Moiré profilometry (CGMP) with real-time 3D measurement and synchronous monitoring video collection is proposed. In this method, a sinusoidal grating and the direct current (DC) component of it are encoded in the blue and red channels of a color composite grating, respectively. This color composite grating is projected onto the measured object, and a corresponding color deformed pattern is sampled by an RGB camera. A monochrome sinusoidal deformed pattern and a flat image are demodulated from the color deformed pattern by color separation. The flat image reflects the DC component of the monochrome sinusoidal deformed pattern and the monitoring image in real time. The DC component of the monochrome sinusoidal deformed pattern is efficiently figured out by multiplying the flat image with an introduced coefficient, even though the DC spectrum and the first-order spectrum of the monochrome sinusoidal deformed pattern overlap. By establishing a color-coded CGMP, the 3D shape of the measured object is reconstructed successfully. Due to its single-shot feature, the 3D information and synchronizing monitoring video are sampled in real time. Some static objects and moving objects are measured to verify the feasibility, validity, and accuracy of the proposed method.