技术领域technical field
本发明涉及在光学三维形貌测量、重建、结构光技术。本发明涉及一种彩色光栅误差补偿方法，更进一步，涉及一种基于投影平面的彩色编码光栅串扰补偿方法。The invention relates to optical three-dimensional shape measurement, reconstruction and structured light technology. The invention relates to a color grating error compensation method, and further relates to a projection plane-based color coded grating crosstalk compensation method.
背景技术Background technique
随着网络通信技术的发展和生产生活需求的扩张，各行业需要一种简单方便的物体三维形貌测量方法。根据测量时是否与被测量物体接触，三维测量分为接触式和非接触式，非接触式三维测量技术在具备同样高精度的条件下还具备传统接触式测量技术所不具备的优点：如测量工件表面保护、大型工件测量、耗时少、便携等。近年来非接触式三维测量技术在文物保护、逆向工程、虚拟现实等领域也得到越来越多的应用。With the development of network communication technology and the expansion of production and living needs, various industries need a simple and convenient method for measuring the three-dimensional shape of objects. According to whether it is in contact with the measured object during measurement, three-dimensional measurement is divided into contact type and non-contact type. The non-contact type three-dimensional measurement technology also has the advantages that traditional contact measurement technology does not have under the condition of the same high precision: such as measurement Workpiece surface protection, large workpiece measurement, less time-consuming, portable, etc. In recent years, non-contact 3D measurement technology has also been more and more applied in the fields of cultural relics protection, reverse engineering, virtual reality and so on.
三维重建技术是三维测量技术的延伸，通过一定的方法获取目标物体的三维形貌信息，并通过一定的算法处理，重建物体的三维轮廓。The 3D reconstruction technology is an extension of the 3D measurement technology. The 3D shape information of the target object is obtained through a certain method, and the 3D profile of the object is reconstructed through a certain algorithm.
基于各种结构光对物体表面进行三维形貌测量的技术不断涌现，并以各自的特点应用于不同的领域。由于条纹图案设计和实现精度高、自动化程度高、易于识别，光学三维测量中投影图案主要趋向于使用条纹模式。条纹结构光投影法是一种基于三角测量原理的主动式光学测量方法。彩色投影图案可以增加基本代码的数量并且确保编码唯一，对运动物体进行重建，所以随着彩色高精度投影仪和电荷耦合元件(CCD)相机的发展，彩色复合正弦条纹投影技术被广泛的研究和应用。彩色条纹的各个颜色通道可以携带更多的相位信息，从而减少图像拍摄次数，提高测量速度。The technology of measuring the three-dimensional shape of the surface of objects based on various structured lights is constantly emerging and applied in different fields with their own characteristics. Due to the high precision of fringe pattern design and realization, high degree of automation, and easy identification, the projection pattern in optical three-dimensional measurement mainly tends to use fringe pattern. The fringe structured light projection method is an active optical measurement method based on the principle of triangulation. The color projection pattern can increase the number of basic codes and ensure the uniqueness of the code, and reconstruct moving objects, so with the development of color high-precision projectors and charge-coupled device (CCD) cameras, color composite sinusoidal fringe projection technology has been extensively researched and developed. application. Each color channel of the color fringe can carry more phase information, thereby reducing the number of image captures and increasing the measurement speed.
存在的问题：彩色编码涉及到的彩色投影仪与彩色CCD相机的通道间颜色串扰问题，会直接影响相位的计算，降低物体三维形貌测量的精度。随着彩色光栅条纹投影技术的发展和广泛应用，颜色通道间串扰消除问题的研究变得越来越重要。采用的投影条纹的图片数量又直接影响到三维重建的快速性和实时性。彩色编码条纹技术在实际应用中存在有许多技术问题需要解决。为了覆盖所有的光谱范围,投影和成像系统颜色通道间存在着串扰和不平衡问题,从而改变了条纹的形状,会在解包裹的绝对相位中产生很大的相位误差最终影响三维重建精度。Existing problems: Color coding involves color crosstalk between the channels of the color projector and the color CCD camera, which will directly affect the calculation of the phase and reduce the accuracy of the three-dimensional shape measurement of the object. With the development and wide application of color grating fringe projection technology, the research on crosstalk elimination between color channels becomes more and more important. The number of pictures of projection stripes used directly affects the rapidity and real-time performance of 3D reconstruction. There are many technical problems to be solved in the practical application of color-coded stripe technology. In order to cover all spectral ranges, there are crosstalk and imbalance problems between the color channels of the projection and imaging systems, which change the shape of the fringes and cause a large phase error in the unwrapped absolute phase, which ultimately affects the accuracy of 3D reconstruction.
发明内容Contents of the invention
有鉴于此，本发明的目的是克服现有技术中的缺陷，提供一种基于投影平面的彩色编码光栅串扰补偿方法。该方法能够在彩色编码光栅三维测量过程中，补偿由于R\G\B通道之间光强的串扰和不平衡所造成的相位误差，避免相位波动得到正确的相位信息。采用较少的投影图片可以满足对待测物体的快速测量，保证三维重建过程中的精度和效率。In view of this, the object of the present invention is to overcome the defects in the prior art, and provide a color-coded grating crosstalk compensation method based on a projection plane. This method can compensate the phase error caused by the crosstalk and unbalance of light intensity between R\G\B channels during the three-dimensional measurement of the color-coded grating, avoiding phase fluctuations and obtaining correct phase information. The use of fewer projection pictures can satisfy the rapid measurement of the object to be measured, and ensure the accuracy and efficiency of the three-dimensional reconstruction process.
本发明的一种基于投影平面的彩色编码光栅串扰补偿方法，该方法包括如下步骤：A color-coded grating crosstalk compensation method based on a projection plane of the present invention, the method includes the following steps:
步骤1：将3频3步黑白条纹图(水平和竖直)和彩色条纹图(水平和竖直)分别投影于标准平板，分别采集这两组图像；Step 1: Project the 3-frequency, 3-step black-and-white fringe pattern (horizontal and vertical) and the color fringe pattern (horizontal and vertical) onto the standard flat panel respectively, and collect these two groups of images respectively;
步骤2：根据步骤1中采集的水平和竖直方向的彩色图像进行通道分离，将彩色变形条纹图分离到R\G\B三个通道中，共得到18(9+9)张单通道图像；Step 2: Channel separation is performed according to the horizontal and vertical color images collected in step 1, and the color deformed fringe image is separated into three channels of R\G\B, and a total of 18 (9+9) single-channel images are obtained ;
步骤3：将上述的两组图像分别解包裹相位，得到黑白条纹和彩色条纹的绝对相位：Gray_PHIu、Gray_PHIν和RGB_PHIu、RGB_PHIν。由投影平面转换方程可以把每组绝对相位分别转换到投影平面，得到黑白条纹和彩色条纹的投影平面坐标：Gray(up,vp)和RGB(up,vp)；Step 3: Unwrap the phases of the above two groups of images respectively to obtain the absolute phases of black and white stripes and color stripes: Gray_PHIu , Gray_PHIν and RGB_PHIu , RGB_PHIν . According to the projection plane conversion equation, each group of absolute phases can be converted to the projection plane respectively, and the projection plane coordinates of black and white stripes and color stripes are obtained: Gray(up ,vp ) and RGB(up ,vp );
步骤4：根据步骤3中的两组绝对相位作差值，可以建立传统黑白条纹和彩色条纹之间的误差查找表err(up,vp)；Step 4: According to the difference between the two sets of absolute phases in step 3, an error lookup table err(up , v p) between traditional black and white stripes and color stripes can be established;
步骤5：根据步骤1和步骤2的方法流程，将彩色条纹图投影于待测实物表面，采集获得彩色变形条纹图像。经过解包裹算法和投影平面转换方程，得到基于投影平面的实物相位坐标：RGB_obj(up,vp)；Step 5: According to the method flow of step 1 and step 2, the color fringe pattern is projected on the surface of the object to be measured, and the color deformed fringe image is acquired. After the unpacking algorithm and the projection plane conversion equation, the physical phase coordinates based on the projection plane are obtained: RGB_obj(up ,vp );
步骤6：根据步骤3和4计算的RGB(up,vp)和err(up,vp)，对步骤5中待测实物的相位坐标RGB_obj(up,vp)进行点对点的串扰补偿。基于最短距离搜索算法，对于RGB_obj(up,vp)中某一点M(up,vp)可以在RGB(up,vp)中找寻一点Pmin(up,vp)作为最短距离坐标，对应于相机坐标系下误差查找表err(up,vp)中一点N(up,vp)为点M(up,vp)的误差补偿量。Step 6: According to RGB(up ,vp ) and err(up ,vp ) calculated in steps 3 and 4,perform point-to-point crosstalk on the phase coordinate RGB_obj(up ,v p)ofthe object to be measured in step 5 compensate. Based on the shortest distance search algorithm, for a point M(up ,vp ) in RGB_obj(up ,vp ), you can find a point Pmin (up ,vp ) in RGB(u p ,v p)as the shortest The distance coordinate correspondsto the error compensation amount of a point N(up ,vp ) in the error lookup table err(up ,vp ) in the camera coordinate system as the point M(up ,vp ).
步骤7：根据步骤6中得到相应点的误差补偿量，在投影平面坐标系下对待测实物RGB_obj(up,vp)进行补偿，经过投影平面转换方程还原得到的绝对相位PHIh和PHIν(取其中的竖直方向PHIv)，进而重建三维形貌。Step 7: According to the error compensation amount of the corresponding point obtained in step 6, compensate the object to be measuredRGB_obj(up , v p) in the projection plane coordinate system, and obtain the absolute phase PHIh and PHIν obtained by restoring the projection plane conversion equation (take the vertical direction PHIv ), and then reconstruct the three-dimensional shape.
进一步，其中步骤1中，所述的黑白条纹和彩色条纹的编码条纹周期一致，高、中、低三个频率应取值合理，尽量取成倍频率值。所述的3频3步彩色编码条纹中各通道调制的投影光栅的光强值应满足：IR＞IG＝IB；Further, in step 1, the coded stripe periods of the black and white stripes and the colored stripes are consistent, and the three frequencies of high, medium and low should take reasonable values, and double frequency values should be taken as much as possible. The light intensity value of the projected grating modulated by each channel in the 3-frequency, 3-step color-coded stripe should satisfy: IR > IG = IB ;
进一步，其中步骤1中，所述彩色条纹图的编码方法和各通道投影的光强值如下列(1)至(3)式所示：Further, wherein in step 1, the encoding method of the color fringe image and the light intensity value projected by each channel are shown in the following formulas (1) to (3):
IR(x,y)＝AR(x,y)+BR(x,y)cos[φ(x,y)-2π/3], (1)IR (x,y)＝AR (x,y)+BR (x,y)cos[φ(x,y)-2π/3], (1)
IG(x,y)＝AG(x,y)+BG(x,y)cos[φ(x,y)], (2)IG (x,y)＝AG (x,y)+BG (x,y)cos[φ(x,y)], (2)
IB(x,y)＝AB(x,y)+BB(x,y)cos[φ(x,y)+2π/3]. (3)IB (x,y)＝AB (x,y)+BB (x,y)cos[φ(x,y)+2π/3]. (3)
其Ii(i＝R\G\B)为R\G\B三个通道的调制光强值；Its Ii (i=R\G\B) is the modulated light intensity value of the three channels of R\G\B;
Ai(i＝R\G\B)为R\G\B三个通道的背景光强，Bi(i＝R\G\B)为调制幅度；Ai (i=R\G\B) is the background light intensity of the three channels of R\G\B, Bi (i=R\G\B) is the modulation amplitude;
其φ(x,y)为待测实物的包裹相位值；Its φ(x, y) is the package phase value of the object to be measured;
进一步，其中步骤2中所述的投影平面转换方程可以用以下(4)至(5)式求得：Further, wherein the projection plane conversion equation described in step 2 can be obtained with the following (4) to (5) formulas:
其中，up和vp分别为u和v方向在投影平面(DMD图像)中的一条线；Among them, up and vp are a line in the projection plane (DMD image) in the direction of u and v respectively;
PHIv、PHIh为竖直和水平方向的绝对相位值；PHIv and PHIh are absolute phase values in the vertical and horizontal directions;
Nv和Nh为光栅图像的条纹数；Nv and Nh are the number of stripes of the grating image;
W和H分别为图像投影图像水平和竖直方向的分辨率；W and H are the horizontal and vertical resolutions of the image projection image respectively;
进一步，其中步骤4中黑白条纹和彩色条纹之间的误差查找表err(up,vp)可由公式(6)求得：Further, the error lookup table err(up ,v p) between black and white stripes and colored stripes in step 4 can be obtained by formula (6):
err(up,vp)＝Gray(up,vp)-RGB(up,vp). (6)err(up ,vp )＝Gray(up ,vp )-RGB(up ,vp ). (6)
其中，Gray(up,vp)和RGB(up,vp)分别为黑白条纹和彩色条纹在投影平面下的绝对相位值；Among them, Gray(up ,vp ) and RGB(up ,v p) are the absolute phasevalues of black and white stripes and color stripes under the projection plane, respectively;
进一步，其中步骤6中所述的最短距离搜索算法，其中对于RGB_obj(up,vp)中某一点M(up,vp)可以在RGB_(up,vp)中找寻一点Pmin(up,vp)作为最短距离坐标。Pmin(up,vp)的搜索过程是迭代计算的，即Pi(up,vp)与M(up,vp)的差值最小时找到对应的点为Pmin(up,vp)；Further, the shortest distance search algorithm described in step 6, wherein for a certain point M(up ,vp ) inRGB_obj (up ,vp ) can find a pointPmin inRGB_ (up ,vp ) (up , vp ) as the shortest distance coordinates. The search process of Pmin (up ,vp ) is calculated iteratively, that is, when the difference between Pi (up ,vp ) and M(up ,vp ) is the smallest, find the corresponding point Pmin (up ,vp );
进一步，其中步骤7中对待测实物RGB_obj(up,vp)进行补偿，补偿后的绝对相位值RGB_ideal(up,vp)可由公式(7)求得：Further, in step 7, the object to be measuredRGB_obj(up ,v p ) is compensated, and the compensated absolute phase value RGB_ideal(up ,v p)canbe obtained by formula (7):
RGB_ideal(up,vp)＝RGB(up,vp)+err(up,vp). (7)RGB_ideal(up ,vp )=RGB(up ,vp )+err(up ,vp ). (7)
进一步，其中，根据公式(4)和(5)，经过投影平面转换方程还原RGB_ideal(up,vp)之后得到的绝对相位PHIu和PHIν，取其中竖直方向的绝对相位PHIv。Further, according to the formulas (4) and (5), the absolute phases PHIu and PHIν obtained after restoringRGB_ideal(up , v p) through the projection plane transformation equation are taken as the absolute phase PHIv in the vertical direction.
根据上述，得到解包裹绝对相位之后，容易进行重建三维形貌。从而实现被测物体的三维形貌高精度快速测量。According to the above, after obtaining the unwrapped absolute phase, it is easy to reconstruct the three-dimensional shape. In this way, high-precision and rapid measurement of the three-dimensional shape of the measured object can be realized.
本发明的有益效果是：本发明公开的一种基于投影平面的彩色编码光栅串扰补偿方法，该方法只需投影3幅彩色光栅条纹图就能得到被测物体的三维形貌信息。创造性地提出了基于投影平面的串扰补偿，将绝对相位转换到投影平面上，点对点，全灰度值进行补偿。相比现有的彩色串扰补偿算法，本发明只需要建立一张误差查找表，进而能对待测物体全场绝对相位值补偿，获得高精度解包裹绝对相位。总的来说，本发明在数字光栅快速三维测量中补偿彩色通道间的串扰和不平衡问题，同时还对其他黑白条纹和彩色条纹轮廓术中存在的误差进行消除。本发明方法由一张彩色图像中可以提取多通道条纹，并且利用投影平面的误差查找表进行串扰补偿，为彩色编码光栅的高精度测量提供一种可行方法，可以应用于快速三维测量领域，适合大规模的推广和应用。The beneficial effects of the present invention are: a projection plane-based color-coded grating crosstalk compensation method disclosed by the present invention, the method only needs to project three color grating fringe images to obtain the three-dimensional shape information of the measured object. The crosstalk compensation based on the projection plane is creatively proposed, and the absolute phase is converted to the projection plane, point-to-point, and full gray value compensation. Compared with the existing color crosstalk compensation algorithm, the present invention only needs to establish an error lookup table, and then can compensate the absolute phase value of the whole field of the object to be measured, and obtain high-precision unwrapped absolute phase. In general, the present invention compensates the crosstalk and unbalance problems between color channels in the digital raster fast three-dimensional measurement, and also eliminates other errors existing in black-and-white fringe and color fringe profilometry. The method of the invention can extract multi-channel fringes from a color image, and use the error lookup table of the projection plane to perform crosstalk compensation, providing a feasible method for high-precision measurement of color-coded gratings, which can be applied to the field of fast three-dimensional measurement, and is suitable for Large-scale promotion and application.
附图说明Description of drawings
为了获得本发明的上述优点和其他特点，以下将参照附图中所示的本发明的具体实施例对以上概述的本发明进行更具体的说明。应理解的是，这些附图仅示出了本发明的典型实施例，因此不应被视为对本发明的范围的限制，通过使用附图，将对本发明进行更具体和更详细的说明和阐述。在附图中：In order to obtain the above advantages and other features of the present invention, a more specific description of the invention outlined above will be made hereinafter with reference to specific embodiments of the invention shown in the accompanying drawings. It should be understood that these drawings only show typical embodiments of the present invention, and therefore should not be considered as limiting the scope of the present invention. By using the accompanying drawings, the present invention will be described and explained more specifically and in detail . In the attached picture:
图1是本发明的测量系统的示意图。Fig. 1 is a schematic diagram of the measurement system of the present invention.
图2是本发明的该投影平面的彩色编码光栅串扰补偿方法的简要实施示意图。FIG. 2 is a schematic diagram of implementation of the color-coded raster crosstalk compensation method for the projection plane of the present invention.
图3是本发明的该投影平面的彩色编码光栅串扰补偿方法的流程示意图。FIG. 3 is a schematic flowchart of the color-coded raster crosstalk compensation method for the projection plane of the present invention.
具体实施方式Detailed ways
如图1至图3所示是依本发明的发明精神提供的一种基于投影平面的彩色编码光栅串扰补偿方法，其通过一个结构光测量系统来实现，该测量系统包括一个终端1、一个投影仪2以及一个工业相机4，该投影仪2和该工业相机4布置在被测物体3前方，并且该投影仪2和该工业相机4均连接于该终端1。该终端1能够控制该投影仪2向该被测量物体投射具有相位信息的条纹光栅，该工业相机4能够实时采集经过该被测量物体表面调制的条纹图像，并将其发送到该终端1以进行分析和后续的操作，例如进行该方法的操作。As shown in Figures 1 to 3, a color-coded grating crosstalk compensation method based on a projection plane is provided according to the inventive spirit of the present invention, which is realized by a structured light measurement system, and the measurement system includes a terminal 1, a projection instrument 2 and an industrial camera 4, the projector 2 and the industrial camera 4 are arranged in front of the measured object 3, and the projector 2 and the industrial camera 4 are both connected to the terminal 1. The terminal 1 can control the projector 2 to project a fringe grating with phase information to the measured object, and the industrial camera 4 can collect the fringe image modulated by the surface of the measured object in real time, and send it to the terminal 1 for Analysis and subsequent operations, such as performing the operations of the method.
结合图1所示，本发明公开一种基于投影平面的彩色编码光栅串扰补偿方法，具体步骤如下：As shown in Figure 1, the present invention discloses a projection plane-based color-coded grating crosstalk compensation method, the specific steps are as follows:
步骤1：由如图1所示的面结构光测量系统，主要由该终端1、该投影仪2、该工业相机4组成，其中该投影仪2和该工业相机4布置在被测物体3前方，其布置位置应保证该工业相机4拍摄范围覆盖该投影仪2的投影范围。例如，在图1这个例子中，该投影仪2和该工业相机4分别位于该被测物体的前方，并且该投影仪2和该工业相机4分别位于该被测物体的两侧，从而该投影仪2能够从该被测物体的前方的一个侧部向该被测物体3投影调制后的条纹图像，该工业相机4能够从该被测物体3的前方的另一个侧部拍摄被投射到该被测物体3的该条纹图像；优选的，将高、中、低(P1＝36、P2＝6、P3＝1)三个频率，三步相移条纹中各通道调制的投影光栅的光强值应满足：IR＞IG＝IB，相位差2π/3的相移条纹分别压制在R\G\B三个通道中。黑白条纹图(水平和竖直)和彩色条纹图(水平和竖直)分别投影于标准平板，分别采集这两组图像。所述彩色条纹图的编码方法和各通道投影的光强值如下列(1)至(3)式所示：Step 1: The surface structured light measurement system as shown in Figure 1 is mainly composed of the terminal 1, the projector 2, and the industrial camera 4, wherein the projector 2 and the industrial camera 4 are arranged in front of the measured object 3 , and its arrangement position should ensure that the shooting range of the industrial camera 4 covers the projection range of the projector 2 . For example, in the example of Fig. 1, the projector 2 and the industrial camera 4 are respectively located in front of the measured object, and the projector 2 and the industrial camera 4 are respectively located on both sides of the measured object, so that the projection The instrument 2 can project the modulated fringe image to the measured object 3 from one side in front of the measured object, and the industrial camera 4 can shoot the fringe image projected onto the measured object 3 from the other side in front of the measured object. The fringe image of the measured object 3; preferably, the three frequencies of high, medium and low (P1=36, P2=6, P3=1), the light intensity of the projected grating modulated by each channel in the three-step phase shift fringe The value should satisfy: IR > IG = IB , and the phase shift fringes with a phase difference of 2π/3 are respectively suppressed in the three channels of R\G\B. Black-and-white fringe images (horizontal and vertical) and color fringe images (horizontal and vertical) are projected on standard flat panels, respectively, and these two groups of images are collected separately. The encoding method of the color fringe image and the light intensity value of each channel projection are shown in the following (1) to (3) formulas:
IR(x,y)＝AR(x,y)+BR(x,y)cos[φ(x,y)-2π/3], (1)IR (x,y)＝AR (x,y)+BR (x,y)cos[φ(x,y)-2π/3], (1)
IG(x,y)＝AG(x,y)+BG(x,y)cos[φ(x,y)], (2)IG (x,y)＝AG (x,y)+BG (x,y)cos[φ(x,y)], (2)
IB(x,y)＝AB(x,y)+BB(x,y)cos[φ(x,y)+2π/3]. (3)IB (x,y)＝AB (x,y)+BB (x,y)cos[φ(x,y)+2π/3]. (3)
其Ii(i＝R\G\B)为R\G\B三个通道的调制光强值；Its Ii (i=R\G\B) is the modulated light intensity value of the three channels of R\G\B;
Ai(i＝R\G\B)为R\G\B三个通道的背景光强，Bi(i＝R\G\B)为调制幅度；Ai (i=R\G\B) is the background light intensity of the three channels of R\G\B, Bi (i=R\G\B) is the modulation amplitude;
其φ(x,y)为待测实物的包裹相位值；Its φ(x, y) is the package phase value of the object to be measured;
步骤2：通过终端1采集的图像来进行通道分离，水平和竖直彩色变形条纹组分别分离到R\G\B三个通道中，得到18(9+9)张单通道图像；Step 2: Carry out channel separation through the images collected by terminal 1, and separate the horizontal and vertical color deformation stripe groups into three channels of R\G\B respectively, and obtain 18 (9+9) single-channel images;
步骤3：将两组图像分别解包裹相位，得到黑白条纹和彩色条纹的绝对相位：Gray_PHIu、Gray_PHIν和RGB_PHIu、RGB_PHIν。由投影平面转换方程可以把每组绝对相位分别转换到投影平面，得到黑白条纹和彩色条纹的投影平面坐标：Gray(up,vp)和RGB(up,vp)，投影平面转换方程可以用以下(4)至(5)式求得：Step 3: Unwrap the phases of the two groups of images respectively to obtain the absolute phases of black and white stripes and color stripes: Gray_PHIu , Gray_PHIν and RGB_PHIu , RGB_PHIν . According to the projection plane conversion equation, each group of absolute phases can be converted to the projection plane respectively, and the projection plane coordinates of black and white stripes and color stripes are obtained: Gray(up ,v p ) and RGB(up ,v p),projection plane conversion equation It can be obtained by the following formulas (4) to (5):
其中，up和vp分别为u和v方向在投影平面(DMD图像)中的一条线；Among them, up and vp are a line in the projection plane (DMD image) in the direction of u and v respectively;
PHIv、PHIh为竖直和水平方向的绝对相位值；PHIv and PHIh are absolute phase values in the vertical and horizontal directions;
Nv和Nh为光栅图像的条纹数；Nv and Nh are the number of stripes of the grating image;
W和H分别为图像投影图像水平和竖直方向的分辨率；W and H are the horizontal and vertical resolutions of the image projection image respectively;
步骤4：根据步骤3中的两组绝对相位作差值，可以建立传统黑白条纹和彩色条纹之间的误差查找表err(up,vp)，可由公式(6)求得：Step 4: According to the difference between the two sets of absolute phases in step 3, an error lookup table err(up ,v p) between traditional black and white stripes and color stripes can be established, which can be obtained by formula (6):
err(up,vp)＝Gray(up,vp)-RGB(up,vp). (6)err(up ,vp )＝Gray(up ,vp )-RGB(up ,vp ). (6)
其中，Gray(up,vp)和RGB(up,vp)分别为黑白条纹和彩色条纹在投影平面下的绝对相位值；Among them, Gray(up ,vp ) and RGB(up ,v p) are the absolute phasevalues of black and white stripes and color stripes under the projection plane, respectively;
步骤5：将投影彩色条纹图通过投影仪2投影到被测物体3表面，并通过工业相机4采集图像，获得水平方向和竖直方向的彩色变形条纹图像。经过解包裹算法和投影平面转换方程，得到基于投影平面的实物相位坐标：RGB_obj(up,vp)；Step 5: Project the projected color fringe image onto the surface of the measured object 3 through the projector 2, and collect images through the industrial camera 4 to obtain color deformed fringe images in the horizontal and vertical directions. After the unpacking algorithm and the projection plane conversion equation, the physical phase coordinates based on the projection plane are obtained: RGB_obj(up ,vp );
步骤6：根据步骤3和4计算的RGB(up,vp)和err(up,vp)，对步骤5中待测实物的相位坐标RGB_obj(up,vp)进行点对点的串扰补偿。基于最短距离搜索算法，对于RGB_obj(up,vp)中某一点M(up,vp)可以在RGB(up,vp)中找寻一点Pmin(up,vp)作为最短距离坐标，对应于相机坐标系下误差查找表err(up,vp)中一点N(up,vp)为点M(up,vp)的误差补偿量。Step 6: According to RGB(up ,vp ) and err(up ,vp ) calculated in steps 3 and 4,perform point-to-point crosstalk on the phase coordinate RGB_obj(up ,v p)ofthe object to be measured in step 5 compensate. Based on the shortest distance search algorithm, for a point M(up ,vp ) in RGB_obj(up ,vp ), you can find a point Pmin (up ,vp ) in RGB(u p ,v p)as the shortest The distance coordinate correspondsto the error compensation amount of a point N(up ,vp ) in the error lookup table err(up ,vp ) in the camera coordinate system as the point M(up ,vp ).
其中对待测实物RGB_obj(up,vp)进行补偿，补偿后的绝对相位值RGB_ideal(up,vp)可由公式(7)求得：Among them, the measured objectRGB_obj(up ,v p ) is compensated, and the compensated absolute phase value RGB_ideal(up ,v p)canbe obtained by formula (7):
RGB_ideal(up,vp)＝RGB(up,vp)+err(up,vp). (7)RGB_ideal(up ,vp )=RGB(up ,vp )+err(up ,vp ). (7)
步骤7：根据步骤6中得到补偿后的绝对相位值RGB_ideal(up,vp)，经过投影平面转换方程还原得到的绝对相位PHIh和PHIν(取其中的竖直方向PHIv)，进而重建三维形貌。Step 7: According to the compensated absolute phase value RGB_ideal(up , vp ) obtained in step 6, the absolute phases PHIh and PHIν obtained by restoring the projection plane conversion equation (take the vertical direction PHIv ), and then Reconstruct the 3D topography.
根据上述，得到解包裹绝对相位之后，容易进行重建三维形貌。从而实现被测物体的三维形貌高精度快速测量。According to the above, after obtaining the unwrapped absolute phase, it is easy to reconstruct the three-dimensional shape. In this way, high-precision and rapid measurement of the three-dimensional shape of the measured object can be realized.
总的来说，本发明在面结构光三维测量系统中，利用彩色复合光栅的多通道性的优势，只需投影3幅彩色光栅条纹图就能得到被测物体的三维形貌信息。创造性地提出了基于投影平面的串扰补偿，将绝对相位转换到投影平面上，点对点，全灰度值进行补偿。相比现有的彩色串扰补偿算法，本发明只需要建立一张误差查找表，进而能对待测物体全场绝对相位值补偿，获得高精度解包裹绝对相位。总的来说，本发明在彩色编码光栅三维测量中补偿彩色通道间的串扰和不平衡问题，同时还对其他黑白条纹和彩色条纹轮廓术中存在的误差进行消除，得到准确的相位信息。In general, the present invention utilizes the multi-channel advantage of the color composite grating in the surface structured light three-dimensional measurement system, and only needs to project three color grating fringe images to obtain the three-dimensional shape information of the measured object. The crosstalk compensation based on the projection plane is creatively proposed, and the absolute phase is converted to the projection plane, point-to-point, and full gray value compensation. Compared with the existing color crosstalk compensation algorithm, the present invention only needs to establish an error lookup table, and then can compensate the absolute phase value of the whole field of the object to be measured, and obtain high-precision unwrapped absolute phase. In general, the present invention compensates for the crosstalk and unbalance between color channels in the three-dimensional measurement of the color-coded grating, and also eliminates the errors existing in other black and white fringe and color fringe profilometry to obtain accurate phase information.
最后说明的是，以上实施例仅用以说明本发明的技术方案而非限制，尽管参照较佳实施例对本发明进行了详细说明，本领域的普通技术人员应当理解，可以对本发明的技术方案进行修改或者等同替换，而不脱离本发明技术方案的宗旨和范围，其均应涵盖在本发明的权利要求范围当中。Finally, it is noted that the above embodiments are only used to illustrate the technical solutions of the present invention without limitation. Although the present invention has been described in detail with reference to the preferred embodiments, those of ordinary skill in the art should understand that the technical solutions of the present invention can be carried out Modifications or equivalent replacements without departing from the spirit and scope of the technical solution of the present invention shall be covered by the claims of the present invention.
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201910481661.3ACN110608687A (en) | 2019-06-04 | 2019-06-04 | A Color-coded Grating Crosstalk Compensation Method Based on Projection Plane |
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201910481661.3ACN110608687A (en) | 2019-06-04 | 2019-06-04 | A Color-coded Grating Crosstalk Compensation Method Based on Projection Plane |
| Publication Number | Publication Date |
|---|---|
| CN110608687Atrue CN110608687A (en) | 2019-12-24 |
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201910481661.3APendingCN110608687A (en) | 2019-06-04 | 2019-06-04 | A Color-coded Grating Crosstalk Compensation Method Based on Projection Plane |
| Country | Link |
|---|---|
| CN (1) | CN110608687A (en) |
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN111174731A (en)* | 2020-02-24 | 2020-05-19 | 五邑大学 | Method and device for double fringe projection phase unwrapping based on color segmentation |
| CN111207697A (en)* | 2020-01-17 | 2020-05-29 | 四川大学 | Phase and modulation acquisition method and device based on lookup table and electronic equipment |
| CN112945140A (en)* | 2021-01-29 | 2021-06-11 | 四川大学 | Color object three-dimensional measurement method based on lookup table and region segmentation |
| CN113465544A (en)* | 2021-06-25 | 2021-10-01 | 安徽农业大学 | Stripe projection three-dimensional measurement nonlinear error correction method |
| CN119676904A (en)* | 2025-02-24 | 2025-03-21 | 深圳市金鼎胜光电股份有限公司 | Multi-spectrum LED detection light source synchronization control method, device, equipment and storage medium |
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101441066A (en)* | 2008-12-23 | 2009-05-27 | 西安交通大学 | Phase de-packaging method of color fringe coding |
| CN101975558A (en)* | 2010-09-03 | 2011-02-16 | 东南大学 | Rapid three-dimensional measurement method based on color grating projection |
| CN102122075A (en)* | 2010-11-30 | 2011-07-13 | 上海大学 | Estimation system and method based on inter-image mutual crosstalk in projection stereoscope visible area |
| CN106094398A (en)* | 2016-08-08 | 2016-11-09 | 哈尔滨理工大学 | Colored compound phase shift fringe structure light projection arrangement and method |
| CN108981606A (en)* | 2018-09-17 | 2018-12-11 | 苏州大学 | A kind of fast illuminated whole audience white light interference microscopic measuring method and its device |
| CN109297435A (en)* | 2018-10-24 | 2019-02-01 | 重庆大学 | A Color Digital Raster Coding Method Reversely Cancelling Nonlinear Errors |
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101441066A (en)* | 2008-12-23 | 2009-05-27 | 西安交通大学 | Phase de-packaging method of color fringe coding |
| CN101975558A (en)* | 2010-09-03 | 2011-02-16 | 东南大学 | Rapid three-dimensional measurement method based on color grating projection |
| CN102122075A (en)* | 2010-11-30 | 2011-07-13 | 上海大学 | Estimation system and method based on inter-image mutual crosstalk in projection stereoscope visible area |
| CN106094398A (en)* | 2016-08-08 | 2016-11-09 | 哈尔滨理工大学 | Colored compound phase shift fringe structure light projection arrangement and method |
| CN108981606A (en)* | 2018-09-17 | 2018-12-11 | 苏州大学 | A kind of fast illuminated whole audience white light interference microscopic measuring method and its device |
| CN109297435A (en)* | 2018-10-24 | 2019-02-01 | 重庆大学 | A Color Digital Raster Coding Method Reversely Cancelling Nonlinear Errors |
| Title |
|---|
| 韩云龙: "结构光三维重建中编解码技术研究", 《中国优秀硕士学位论文全文数据库 信息科技辑》* |
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN111207697A (en)* | 2020-01-17 | 2020-05-29 | 四川大学 | Phase and modulation acquisition method and device based on lookup table and electronic equipment |
| CN111207697B (en)* | 2020-01-17 | 2021-07-02 | 四川大学 | Phase and modulation acquisition method, device and electronic device based on look-up table |
| CN111174731A (en)* | 2020-02-24 | 2020-05-19 | 五邑大学 | Method and device for double fringe projection phase unwrapping based on color segmentation |
| CN111174731B (en)* | 2020-02-24 | 2021-06-08 | 五邑大学 | Method and device for double fringe projection phase unwrapping based on color segmentation |
| CN112945140A (en)* | 2021-01-29 | 2021-06-11 | 四川大学 | Color object three-dimensional measurement method based on lookup table and region segmentation |
| CN113465544A (en)* | 2021-06-25 | 2021-10-01 | 安徽农业大学 | Stripe projection three-dimensional measurement nonlinear error correction method |
| CN113465544B (en)* | 2021-06-25 | 2022-04-08 | 安徽农业大学 | Stripe projection three-dimensional measurement nonlinear error correction method |
| CN119676904A (en)* | 2025-02-24 | 2025-03-21 | 深圳市金鼎胜光电股份有限公司 | Multi-spectrum LED detection light source synchronization control method, device, equipment and storage medium |
| CN119676904B (en)* | 2025-02-24 | 2025-04-18 | 深圳市金鼎胜光电股份有限公司 | Multispectral LED detection light source synchronous control method, device, equipment and storage medium |
| Publication | Publication Date | Title |
|---|---|---|
| CN110608687A (en) | A Color-coded Grating Crosstalk Compensation Method Based on Projection Plane | |
| CN107607060B (en) | A kind of phase error compensation method applied in the measurement of grating tripleplane | |
| CN110288642B (en) | Three-dimensional object rapid reconstruction method based on camera array | |
| CN108267097B (en) | 3D reconstruction method and device based on binocular 3D scanning system | |
| CN108151671B (en) | A three-dimensional digital imaging sensor, three-dimensional scanning system and scanning method thereof | |
| TWI414748B (en) | Method for simultaneuos hue phase-shifting and system for 3-d surface profilometry using the same | |
| CN101813461B (en) | Absolute phase measurement method based on composite color fringe projection | |
| CN109556535B (en) | A one-step reconstruction method of 3D surface shape based on color fringe projection | |
| CN107576280A (en) | Fringe projection 3 D measuring method and device based on parallel four Color Channel | |
| CN105091750A (en) | Projector calibration method based on double four-step phase shift | |
| CN107990846B (en) | Active-passive combined depth information acquisition method based on single-frame structured light | |
| CN113465545B (en) | Three-dimensional measurement system based on high-speed LED array and measurement method thereof | |
| CN110006365B (en) | Phase unwrapping method and device based on two-dimensional lookup table and electronic equipment | |
| CN113551617A (en) | Binocular and dual-frequency complementary three-dimensional surface measurement method based on fringe projection | |
| CN102829736A (en) | Three-dimensional fingerprint sensing system | |
| CN111811433A (en) | Structured light system calibration method, device and application based on red and blue orthogonal stripes | |
| CN113763540A (en) | Three-dimensional reconstruction method and equipment based on speckle fringe hybrid modulation | |
| CN117073579A (en) | Structured light binocular three-dimensional measurement system and method based on stripe projection | |
| CN115615358A (en) | A Color Crosstalk Correction Method for Color Structured Light Based on Unsupervised Deep Learning | |
| CN105303572A (en) | Depth information acquisition method on the basis of combination of activeness and passiveness | |
| CN116429022A (en) | A Phase Unwrapping Method for Color Phase Order Codec | |
| CN117450955B (en) | Three-dimensional measurement method of thin objects based on spatial annular features | |
| CN107504919B (en) | Wrapped phase three-dimension digital imaging method and device based on phase mapping | |
| CN114234851A (en) | A three-dimensional measurement method of modulated binary code at periodic edge | |
| Wang et al. | A fast and precise three-dimensional measurement system based on multiple parallel line lasers |
| Date | Code | Title | Description |
|---|---|---|---|
| PB01 | Publication | ||
| PB01 | Publication | ||
| SE01 | Entry into force of request for substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| WD01 | Invention patent application deemed withdrawn after publication | Application publication date:20191224 | |
| WD01 | Invention patent application deemed withdrawn after publication |