Method and system for measuring three-dimensional shape

Abstract

The invention discloses a method for measuring a three-dimensional shape. The method comprises the steps that M first phase-shift images and N first two-value random speckle images are periodically projected to an object to be measured, wherein N first two-value random speckle images in the current period are different and also different from N first two-value random speckle images in the last period; M pairs of corresponding second phase-shift images and N pairs of corresponding second two-value random speckle images are obtained by periodically collecting the images; according to M pairs ofsecond phase-shift images in the current period, a wrapping phase position is calculated and obtained; according to N pairs of second two-value random speckle images in the last period and N pairs ofsecond two-value random speckle images in the current period, in combination with the wrapping phase position, disparity map calculation is conducted, and then the three-dimensional shape of the object to be measured is restored according to a disparity map. In addition, the invention further discloses a system for measuring the three-dimensional shape. According to the method and system, the precision and efficiency for measuring the three-dimensional shape of the object to be measured can be effectively improved.

Description

technical field [0001] The invention relates to three-dimensional surface measurement technology, in particular to a method and system for three-dimensional shape measurement. Background technique [0002] Three-dimensional surface measurement has a wide range of applications in product inspection, reverse engineering, 3D printing, anthropometry, human-computer interaction, animation production and other fields. Currently popular methods include laser scanning methods, stereo vision methods, time-of-flight (ToF) methods, and structured light methods. [0003] Among them, the structured light method based on fringe projection is widely used due to its advantages of high efficiency and low cost. The corresponding phase shift algorithm needs to project at least 3 phase shift images to the surface of the measured object, and then process at least 3 pairs of phase shift images corresponding to the above phase shift images collected by the stereo camera to obtain the phase at eac...

AI Technical Summary

Problems solved by technology

[0004] However, in traditional dephasing methods, the matching process usually only compares in the neighborhood space of candidate matching pixel pairs

However, in the actual measurement process, due to changes in the surface of the measured object such as illumination and / or appearance, this method of pixel point matching only in the two-dimensional matching window will produce coarse matching errors

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