Computing device and method of image matching

A computing device, comprising:

• a processor;
• and a storage device that stores one or more programs, when executed by the at least one processor, cause the at least one processor to perform an image matching method, the computing device being connected to a measurement device, the measurement device comprising a projector, a left camera, and a right camera, the method comprising:
• receiving a number M of frequencies of gratings, cycles of gratings with each of the frequencies, and phase shifting times N;
• controlling the projector to project gratings with each of the frequencies on an object according to the phase shifting times N, and acquiring a number N of left grating images captured by the left camera and a number N of right grating images captured by the right camera of the gratings with each of the frequencies on the object;
• classifying the left grating images into groups of left grating images and classifying the right grating images into groups of right grating images according to the frequencies of the gratings, each group of left grating images and each group of right grating images corresponding to one of the frequencies;
• computing a luminous intensity of each pixel in each of the left grating images and the right grating images;
• computing a phase principal value of pixels having same coordinates in each group of left grating images of the gratings with each of the frequencies according to luminous intensities of the pixels having same coordinates in the group of left grating images and an N-step phase shifting method, and computing a phase principal value of pixels having same coordinates in each group of right grating images of the gratings with each of the frequencies according to luminous intensity of the pixels having same coordinates in the group of right grating images and the N-step phase shifting method;
• computing a phase of the pixels having same coordinates in the left grating images according to the phase principal value of the pixels having same coordinates in each group of left grating images, and obtaining a first phase grayscale image according to the phase of the pixels having same coordinates in each group of left grating images, and computing a phase of the pixels having same coordinates in the right grating images according to the phase principal value of the pixels having same coordinates in each group of right grating images, and obtaining a second phase grayscale image according to the phase of the pixels having same coordinates in each group of right grating images;
• matching the first phase grayscale image and the second phase grayscale image and obtaining a matched image.

A non-transitory storage medium having stored thereon instructions that, when executed by a processor of a computing device, the computing device being connected to a measurement device, the measurement device comprising a projector, a left camera, and a right camera, causes the processor to perform an image matching method in the computing device, wherein the method comprises:

• receiving a number M of frequencies of gratings, cycles of gratings with each of the frequencies, and phase shifting times N;
• controlling the projector to project gratings with each of the frequencies on an object according to the phase shifting times N, and acquiring a number N of left grating images captured by the left camera and a number N of right grating images captured by the right camera of the gratings with each of the frequencies on the object;
• classifying the left grating images into groups of left grating images and classifying the right grating images into groups of right grating images according to the frequencies of the gratings, each group of left grating images and each group of right grating images corresponding to one of the frequencies;
• computing a luminous intensity of each pixel in each of the left grating images and the right grating images;
• computing a phase principal value of pixels having same coordinates in each group of left grating images of the gratings with each of the frequencies according to luminous intensities of the pixels having same coordinates in the group of left grating images and an N-step phase shifting method, and computing a phase principal value of pixels having same coordinates in each group of right grating images of the gratings with each of the frequencies according to luminous intensity of the pixels having same coordinates in the group of right grating images and the N-step phase shifting method;
• computing a phase of the pixels having same coordinates in the left grating images according to the phase principal value of the pixels having same coordinates in each group of left grating images, and obtaining a first phase grayscale image according to the phase of the pixels having same coordinates in each group of left grating images, and computing a phase of the pixels having same coordinates in the right grating images according to the phase principal value of the pixels having same coordinates in each group of right grating images, and obtaining a second phase grayscale image according to the phase of the pixels having same coordinates in each group of right grating images;
• matching the first phase grayscale image and the second phase grayscale image and obtaining a matched image.