Fig. 1. Distribution of Gray code words

Fig. 2. Composite fringe images based on shifting Gray code encoding

Fig. 3. Pattern sequences to be projected

Fig. 4. Binarization process

Fig. 5. Correspondence between C_j(x,y,m) and B_j(x,y,m)

Fig. 6. Correspondence between wrapped phase and two sets of fringe orders. (a) Fringe order obtained by traditional Gray code decoding; (b) wrapped phase; (c) fringe order obtained by shifting Gray code decoding

Fig. 7. Phase unwrapping process of extended 32-period fringe. (a) Wrapped phase; (b) 4 primary unwrapping phase of 8-period fringe and unwrapped phase of reference plane; (c) unwrapped phase of object to be tested

Fig. 8. STD distribution of absolute phase of standard plane corresponding to different P

Fig. 9. Binarization results of Gray code patterns corresponding to different P. (a) P=0.5; (b) P=0.6; (c) P=0.7; (d) P=0.8

Fig. 10. 3D measurement results of isolated objects. (a) One frame of composite deformed pattern; (b) white field pattern obtained by camera; (c) restored phase using traditional Gray code method; (d) restored phase using proposed method

Fig. 11. Measurement results of flower model with nonuniform surface reflectivity. (a) One frame of composite deformed pattern; (b) white field pattern obtained by camera; (c) restored phase using traditional Gray code method; (d) restored phase using proposed method

Fig. 12. Dynamic 3D measurement results of fan during rotation. (a) Six frames of composite fringe patterns obtained by high-speed camera; (b) white fields with object information; (c) restored phase results corresponding to Fig. 12(a)