Equipment and method for promptly performing calibration and verification of intrinsic and extrinsic parameters of a plurality of image capturing elements installed on electronic device
The present invention is to provide an image processing equipment and method, for enabling an electronic device having a plurality of image capturing elements installed thereon to capture calibration sample images of a parameter calibration module and verification sample images of a parameter verification module, wherein the parameter calibration module is formed by four calibration identification boards each having a chess board pattern printed thereon and arranged parallelly in a predetermined angle with each other, the parameter verification module is formed by four verification identification boards each having a chess board pattern printed thereon and arranged in parallel with each other, so as for the electronic device to promptly calibrate the intrinsic and extrinsic parameters of the mage capturing elements according to the calibration sample images and then to promptly verify the correctness of the calibrated intrinsic and extrinsic parameters according to the verification sample images.
1. A method for performing calibration and verification of intrinsic and extrinsic parameters of a plurality of image capturing elements installed on electronic device, which is applied to the electronic device and comprises steps, to be performed by the electronic device, of:
enabling image capturing elements to be positioned at a fixed distance in front of the center of a parameter calibration module, wherein the parameter calibration module is formed by four calibration identification boards each having a chess pattern printed thereon and arranged in parallel in a predetermined angle with each other, and the chess pattern includes a plurality of chess lattices and a plurality of identification points representing the corner points of each chess lattice, respectively;
enabling the image capturing elements to capture calibration sample images of the identification points on the calibration identification boards, respectively;
identifying image coordinates of all the identification points on the calibration sample images;
recording and storing the image coordinates of all the identification points on the calibration sample images in a sequential order; and
calibrating the intrinsic and extrinsic parameters of the image capturing elements through an optimization algorithm according to the image coordinates of the corresponding identification points on the calibration sample images;
after the intrinsic and extrinsic parameters of the image capturing elements are calibrated:
enabling the image capturing elements to be positioned at a fixed distance in front of the center of a parameter verification module, wherein the parameter verification module is formed by four verification identification boards each having a chess pattern printed thereon and arranged in parallel with each other, and the chess pattern includes a plurality of chess lattices and a plurality of identification points representing the corner points of each chess lattice, respectively;
enabling the image capturing elements to capture the verification sample images of the identification points on the verification identification boards, respectively;
identifying the image coordinates of the identification points on the verification sample images;
recording and storing the image coordinates of all the identification points on the verification sample images s in a sequential order;
analyzing and correcting the offset between the image coordinates of the corresponding identification points on the verification sample images, respectively;
determining whether the offset between the image coordinates of the corresponding identification points on the verification sample images is lower than a predetermined threshold value; and
when it is determined that the offset between the image coordinates of the corresponding identification points on the corresponding verification sample images is lower than a predetermined threshold value, assigning the calibrated intrinsic and extrinsic parameters of the image capturing elements as the default intrinsic and extrinsic parameters of the image capturing elements eligible to be used by the electronic device in performing a precise and clear optical zooming mechanism, in performing a precise and clear stitching mechanism for producing a panoramic image of high image quality, or in performing a reconstructing mechanism for producing a 3D image of high image quality by utilizing the images respectively captured by the image capturing elements according to the default intrinsic and extrinsic parameters of the image capturing elements.
2. The method of claim 1 , wherein the optimization algorithm is one of a gradient descent algorithm, a conjugate gradient algorithm, or a Levenberg-Marquardt algorithm.
3. The method of claim 2 , wherein the fixed distance is in an amount for allowing the fields of view of the image capturing elements to clearly capture all the identification points on the calibration identification boards.