Fig. 1. Steps of 3D reconstruction by phase-shift profilometry

Fig. 2. Correspondence between absolute phase and cosine truth value. (a) Absolute phase; (b) cosine truth value

Fig. 3. Comparison of encoding patterns. (a) Single-frequency encoding; (b) multi-frequency sequential encoding; (c) multi-frequency alternate encoding

Fig. 4. Correspondence between absolute phase and cosine truth value. (a) Absolute phase; (b) cosine truth value

Fig. 5. Correspondence between truncated phase and cosine truth value. (a) Truncated phase; (b) cosine truth value

Fig. 6. Iterative interpolation

Fig. 7. Flow chart of proposed algorithm

Fig. 8. Frequency encoding mode

Fig. 9. Physical image of experimental system

Fig. 10. Validity verification experiment. (a1)(a2) Pattern projecting; (b1) phase unwrapping; (b2) phase correcting; (b3) 3D reconstruction; (b4) sphere reconstruction

Fig. 11. Unwrapping accuracy verification experiment (medium frequency mode). (a1)(a2) Phase unwrapping results of proposed method; (b) phase unwrapping results of multi-frequency progressive; (c) 3D reconstruction

Fig. 12. Unwrapping accuracy verification experiment (high frequency mode). (a1) (b1) (c1) Additional projected patterns for different methods; (a2) (b2) (c2) phase unwrapping results for different methods; (a3) (b3) (c3) 3D reconstruction for different methods