Generalized phase evaluation for stereophotogrammetric correspondence assignment.

Area of Science:

• Optics and Photonics
• Computer Vision
• Metrology

Background:

• Phase-shifting fringe projection is crucial for 3D shape measurement in profilometry and stereophotogrammetry.
• Existing phase evaluation schemes vary, impacting the accuracy of correspondence mapping between camera views.
• The nominal phase value serves as a key image feature for establishing stereo correspondence.

Purpose of the Study:

• To investigate the role and properties of phase evaluation in stereophotogrammetric correspondence mapping.
• To generalize the classical phase evaluation function for improved accuracy.
• To experimentally compare classical and generalized phase evaluation methods.

Main Methods:

• Analysis of classical phase evaluation function properties for correspondence mapping.
• Derivation of a generalized phase evaluation function for stereo image sequences.
• Experimental comparison of correspondence assignment using classical versus generalized phase evaluation.

Main Results:

• The essential properties of the classical phase evaluation function for accurate correspondence were identified.
• A generalized phase evaluation function was derived, offering potential for enhanced accuracy.
• Experimental results demonstrated differences in correspondence assignment between the two methods.

Conclusions:

• Generalized phase evaluation offers improved accuracy for correspondence mapping in stereophotogrammetry.
• The derived generalized function is applicable to sequences of stereo images.
• This work contributes to advancing high-accuracy 3D shape measurement techniques.