Fig. 1. Schematic diagram of measurement system

Fig. 2. Flow chart of DIC-assisted temporal phase shift fringe projection profilometry

Fig. 3. Schematic diagram of localization of contour line. (a) Phase principal value image; (b) grayscale-jump contour line localized by Canny operator; (c) phase-jump contour line; (d) outline of object to be measured

Fig. 4. Schematic diagram of binocular stereo vision system

Fig. 5. Diagram of relation between depth and phase of point of interest Pj

Fig. 6. Schematic diagram of phase unwrapping. (a) Determine roughly estimated phase of point P_j on contour line; (b) determine fringe order of continuous phase region between contour lines

Fig. 7. Schematic diagram of experimental system construction

Fig. 8. Phase unwrapping experiment on surface of stacked wooden blocks. (a) Phase shift image (δ1=π/2); (b) phase principal value image; (c) phase continuous regions and grayscale-jump contour line; (d) speckle image; (e) roughly estimated phase transformed by calibrated model; (f) phase unwrapping diagram; (g) three-dimensional morphology after deducting reference plane

Fig. 9. Comparison of measurement methods for surface topography reconstruction of wood blocks. (a) Three-dimensional morphology obtained by stereo DIC method; (b) three-dimensional morphology obtained by fringe projection profilometry

Fig. 10. Comparison of fringe order obtained by two methods. (a) Fringe order of proposed method; (b) fringe order of three-frequency four-step phase shift method; (c) fringe order difference diagram

Fig. 11. Evaluation of measurement accuracy. (a) Selected local absolute phase; (b) measurement deviation of proposed method

Fig. 12. Topography measurement including astronaut model and table tennis scenes. (a) Phase shift image (δ1=π/2); (b) phase principal value image; (c) phase continuous regions and grayscale-jump contour line; (d) speckle image; (e) roughly estimated phase transformed by calibrated model; (f) phase unwrapping diagram; (g) three-dimensional morphology after deducting reference plane