A three-dimensional measurement method for structured light of colored objects based on phase shifting and multi-bit codes

Abstract

The invention provides a three-dimensional measurement method for structured light of a colored object based on phase shifting and multi-bit codes, and belongs to the field of three-dimensional measurement of structured light. The method of the present invention utilizes the multi-element code to uniquely encode the fringe order, and embeds the encoding sequence of the multi-element code into an additional frame of phase-shifting fringe pattern, and combines it with the sinusoidal fringe pattern used to obtain the wrapped phase during decoding, and obtains from the phase difference The code elements of each period can be decoded by arranging the code elements of a single row from left to right; using the maximum probability method to obtain the order of each periodic fringe from the decoding sequence, so as to obtain the continuous phase information of the object surface; The deformed fringe images collected by the camera are accumulated, and the results are normalized to 0~255 to obtain the color information of the object surface; the continuous phase information and color information are used to reconstruct the color three-dimensional information of the object.

Description

1. Technical field [0001] The invention relates to the field of three-dimensional measurement of structured light, in particular to a method for three-dimensional measurement of structured light of colored objects based on phase shifting and multi-bit codes. 2. Background technology [0002] Three-dimensional measurement technology can be divided into two categories: active measurement and passive measurement according to whether the light information is actively projected during the measurement process. As a kind of active measurement method, the structured light three-dimensional measurement technology based on fringe projection is widely used in the fields of computer vision, medical diagnosis, industrial inspection and surface modeling due to its high precision and low cost. Take fine measurements. In the three-dimensional measurement of structured light based on fringes, the correct determination of the fringe order of each pixel in the imaging plane of the camera is a...

AI Technical Summary

Problems solved by technology

[0003] At present, when the time-based phase resolution algorithm encodes the order of stripes, it mostly uses a ladder gray pattern of more than or equal to 3 frames for encoding. When the object to be tested is colored, the color information on the surface of the object and the ladder gray pattern of the projected additional pattern After the gray scale is mixed, it is impossible to determine whether the gray scale is from the coding pattern or the color of the object itself, resulting in a phase resolution error; and the additional pattern of projecting multiple frames greatly reduces the timeliness of measurement, and cannot be effectively applied to the rapid detection of colored objects. 3D measurement

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