TWI427262B - Computer system and method for adjusting profile light - Google Patents

Description

Contour light adjustment method and computer system thereof

The invention relates to a light source adjusting method and a computer system thereof, in particular to a contour light adjusting method and a computer system thereof.

Image measurement is currently the most widely used measurement method in the field of precision measurement. This method not only has high precision, but also has fast measurement speed. Image measurement is mainly used for measuring the dimensional error and shape error of parts or components, which plays an important role in ensuring product quality.

The conventional image measuring method uses an industrial optical lens with a high-resolution Charged Coupled Device (CCD) to obtain an image of a workpiece or a component to be tested through an image capturing card. The measuring method is for a workpiece or a component. Many precision measurements have achieved high precision.

However, in the previous image measurement process, the image light source emitted by the light-emitting device on the image measuring machine may be different, for example, the intensity and brightness may be different, even for the same type of light-emitting device (eg, the same specification). The source of the image emitted by the light source device is also different. When the CCD image is processed, the image sharpness of the acquired image is greatly deviated, so that the repeatability of the image measurement by different machines for the same workpiece is poor. As a result, the accuracy is not high.

In the prior art, the adjustment of the light source, especially the contour light, is manually performed by the measuring personnel, and the intensity of the light source is greatly affected by the subjective consciousness of the individual, and the error of the measurement result is easily caused. At the same time, manual adjustment requires the measurement personnel to focus on the image of the workpiece and the light source adjuster of the image measuring machine, which has a certain labor intensity.

In view of the above, it is necessary to provide a contour light adjustment method and a computer system thereof, which can improve the repeatability and accuracy of image measurement and reduce the labor intensity of the measurement personnel.

A method for adjusting a contour light, the method comprising: adjusting contour light to an initial level; acquiring an image of an area of the initial level where the contour light needs to be adjusted, and performing average filtering and binarization processing on the image; and setting the contour light a variable involved in the adjustment process; calculating a level corresponding to the best contour light of the image according to the above variable; and automatically adjusting the contour light according to the calculated level.

A computer system for adjusting contour light, the computer system comprising an image processing unit, a calculation unit, and a contour light adjustment unit. The image processing unit is configured to adjust the contour light of the image measuring machine to an initial level, and perform average filtering and binarization processing on the image of the area where the contour light needs to be adjusted. The calculation unit is configured to set a variable involved in the contour light adjustment process, and calculate a level of the best contour light corresponding to the image according to the variable. The contour light adjustment unit is configured to automatically adjust the contour light according to the level calculated by the calculation unit.

Compared with the prior art, the contour light adjustment method and the computer system thereof analyze the relationship between the contour light and the workpiece image to calculate the level corresponding to the optimal contour light, thereby automatically adjusting the contour light to improve the repeatability of the image measurement. With precision, it reduces the labor intensity of the measurement personnel.

1‧‧‧Image measuring machine

2‧‧‧Workpiece

3‧‧‧ computer

10‧‧‧Light source regulator

12‧‧‧Charge-coupled device

30‧‧‧Contour light adjustment system

300‧‧‧Image Processing Unit

302‧‧‧Computation unit

304‧‧‧Contour light adjustment unit

S1‧‧‧Select the area where the contour light needs to be adjusted in the image of the workpiece

S3‧‧‧ to adjust the outline light to an initial level

S5‧‧‧ Obtain images of selected areas and average them and binarize them

S7‧‧‧Set the variables involved in the contour light adjustment process

S9‧‧‧ Calculate the level corresponding to the best contour light by the iterative approximation method according to the above variables

S11‧‧‧Automatic contour light adjustment according to the calculated level

BRIEF DESCRIPTION OF THE DRAWINGS Figure 1 is a diagram showing the operating environment of a preferred embodiment of a computer system for contour light adjustment of the present invention.

2 is a graph showing changes in gray value of images under different contours of the present invention.

3 is a functional unit diagram of a computer system for contour light adjustment of the present invention.

Fig. 4 is a flow chart showing the operation of the preferred embodiment of the contour light adjusting method of the present invention.

FIG. 5 is a specific operational flowchart of the present invention for calculating the level corresponding to the optimal contour light by using the iterative approximation method.

Referring to Figure 1, there is shown an operational environment diagram of a preferred embodiment of a computer system for contour light adjustment of the present invention. The operating environment map includes an image measuring machine 1, a workpiece 2 measured by the image measuring machine 1, and a computer 3. The image measuring machine 1 may be an image measuring instrument of the "VMS" series, which includes a light source adjuster 10 and a charge coupled device 12. The charge coupled device 12 is used to image the workpiece 2, and the light source adjuster 10 is used to adjust the brightness of the contour light emitted by the image measuring machine 1 during the imaging. A contour light adjustment system 30 is stored in the computer 3 for controlling the light source adjuster 10 for automatic contour light adjustment.

In the present embodiment, the light source adjuster 10 adjusts the intensity of the contour light by using "0~100" levels, and each level corresponds to the brightness of a contour light according to the color of the workpiece 2 and the background color placed on the workpiece 2. That is to say, different workpieces 2 or the same workpiece 2 are placed in different backgrounds, and the brightness of the contour light indicated by the same level may be different.

In addition, the brightness in this embodiment can be indicated by the gradation value of the image. As we all know, the gray value of the image ranges from 0 to 255. When the light source adjuster 10 is adjusted to the 0 level, the image of the workpiece 2 must be black, that is, the gray value of the image is 0, and the brightness of the contour light is low; and when the light source adjuster 10 is adjusted to the 100 level, the workpiece 2 Image is white That is, the gray value of the image is 255, and the brightness of the contour light is high. As shown in FIG. 2, it is a graph of gray value variation of images under different contour lights of the present invention.

Referring to Figure 3, there is shown a functional unit diagram of the contoured light adjustment system 30 of the present invention. The contour light adjustment system 30 is a computer program, and can be divided into an image processing unit 300, a calculation unit 302, and a contour light adjustment unit 304 according to functions, and the functions thereof can be specifically described through the flowchart shown in FIG. 4: as shown in FIG. It is a flowchart of the operation of the preferred embodiment of the contour light adjusting method of the present invention.

In step S1, the charge coupled device 12 images the workpiece 2, and the user selects an area in the image of the workpiece 2 where the contour light of the workpiece 2 needs to be adjusted, which is usually a boundary region.

In step S3, the user adjusts the light source adjuster 10 manually so that the contour light of the image measuring machine 1 is adjusted to an initial level. In this embodiment, the initial level may not be too low or too high, and the image at the initial level must be a user-recognizable image, for example, it may not be “0 level” or “100 level”. The initial level in the preferred embodiment is "10 levels."

In step S5, the image processing unit 300 acquires an image of the selected area under the initial level, and performs average filtering and binarization processing on the image to reduce or eliminate the influence of image noise, improve image quality, and make the workpiece 2 The image can sense the contour light, that is, the gray value of the processed image can change with the intensity of the contour light. The binarization process refers to converting a plurality of grayscale images into images having only two gray levels, so as to facilitate feature highlighting and graphic recognition, and the processed image is black and white, that is, Gray values are 0 and 255.

In step S7, the calculation unit 302 sets a variable involved in the contour light adjustment process, which includes the upper adjacent level Vm, the lower adjacent level Vn, and the current level Vc of the level Vp corresponding to the optimum contour light.

In step S9, the calculating unit 302 calculates the level Vp corresponding to the optimal contour light of the processed image by using the iterative approximation method according to the above variable.

In step S11, the contour light adjustment unit 304 automatically adjusts the contour light according to the level Vp calculated by the calculation unit 302.

Referring to Fig. 5, a specific operation flow chart for calculating the level Vp by the iterative approximation method in step S9 is shown.

In step S900, the calculation unit 302 initializes the variables involved in the contour light adjustment process, that is, the calculation unit 302 sets the upper adjacent level Vm=100, and the lower adjacent level Vn=1.

In step S902, the current level Vc of the contour light is adjusted to Vc=(Vm+Vn)/2, the image at the current level Vc is acquired, and the gray value Gc of the image is calculated. Specifically, the calculation unit 302 acquires the gradation of each primitive in the image, adds the gradations of all the primitives, and then divides the total number of primitives to obtain the grayscale value Gc of the image. During the digitization process of the image, the image data is uncompressed, and is saved through a continuous memory area. Generally, the gray value of each primitive in the image can be accessed through the pointer, for example, if the width is W, the first primitive address of the image data of the 8-bit grayscale image with height H is pixel, and the gray value of the (i, j)th primitive can be transmitted through "pixel[j*W+i ]" or "*(pixel+j*W+i)" for reading.

In step S904, it is determined whether the gradation value Gc is smaller than the gradation value Gp of the image under the optimal contour light. The gray value Gp can take an intermediate value of 0 to 255. In the preferred embodiment, Gp Take 125.

If Gc=Gp, go directly to step S912; if Gc<Gp, in step S906, the calculation unit 302 takes the current level Vc as the next adjacent level, that is, makes Vn=Vc, and then proceeds to step S910.

On the other hand, if Gc>Gp, in step S908, the calculation unit 302 takes the current level Vc as the upper adjacent level, that is, makes Vm=Vc, and then proceeds to step S910.

In step S910, the calculating unit 302 compares whether the difference (Vm-Vn) between the current upper adjacent level Vm and the current lower adjacent level Vn is less than a best predetermined value V0. In the preferred embodiment, the optimal predetermined value V0 is equal to two.

If (Vm - Vn) < V0, then in step S912, it is indicated that the above-mentioned calculation and the adjusted level are the level Vp corresponding to the optimum contour light.

On the other hand, if Vm-Vn>=V0, the process returns to step S902, and the current upper adjacent level Vm and the current lower adjacent level Vn are used as calculation conditions to call the iterative approximation formula Vc=(Vm+Vn)/2 to perform calculation and adjustment again. . For example, if the gradation value calculated in step S902 is Gc1, the calculation unit 302 further calculates Vc2 from the current upper neighboring level Vm and the current lower neighboring level Vn, and then acquires the gradation value of the image of the level Vc2. Gc2, as shown in FIG. 2, step S904 to step S912 are repeatedly executed until the level Vp corresponding to the adjustment of the optimum contour light is calculated.

The present invention has been described above in terms of preferred embodiments, and is not intended to limit the invention. Any person skilled in the art will be able to make changes and refinements without departing from the spirit and scope of the invention, and the scope of the invention is defined by the scope of the appended claims.

S1‧‧‧Select the area where the contour light needs to be adjusted in the image of the workpiece

S3‧‧‧ to adjust the outline light to an initial level

S5‧‧‧ Obtain images of selected areas and average them and binarize them

S7‧‧‧Set the variables involved in the contour light adjustment process

S9‧‧‧ Calculate the level corresponding to the best contour light by the iterative approximation method according to the above variables

S11‧‧‧Automatic contour light adjustment according to the calculated level

Claims (9)

A contour light adjustment method, the method comprising: adjusting contour light to an initial level; acquiring an image of an area of the initial level where the contour light needs to be adjusted, and performing average filtering and binarization processing on the image; setting the contour light a variable involved in the adjustment process, the variable includes an upper adjacent level Vm of the level Vp corresponding to the best contour light, a lower adjacent level Vn, and a current level Vc; and a level corresponding to the optimal contour light of the image is calculated according to the above variable The method includes the steps of: (a) initializing each variable, the variable including the upper adjacent level Vm of the level corresponding to the best contour light and the lower adjacent level Vn, that is, the upper adjacent level Vm=100, and the next adjacent level Vn=1; b) adjusting the level of the contour light to Vc=(Vm+Vn)/2; (c) acquiring the image at the level Vc and the gray value Gc of the image; (d) determining whether the gray value Gc is smaller than The gray value Gp of the image under the optimal contour light; (e) if Gc < Gp, the level Vc is the next adjacent level, that is, Vn=Vc, and if Gc>Gp, the level Vc For the adjacent level, that is, make Vm=Vc; (f) compare the current upper adjacent level Vm Whether the difference (Vm-Vn) of the next adjacent level Vn is less than a best predetermined value V0; and (g) if Vm-Vn < V0, it indicates that the above calculation is the level corresponding to the adjusted level of the optimum contour light; And (h) if Vm-Vn>=V0, return to step (b); and automatically adjust the contour light according to the calculated level. The contour light adjustment method according to claim 1, wherein the gray value Gp of the image under the optimal contour light can take an intermediate value of 0 to 255. The contour light adjustment method of claim 2, wherein the level of the contour light comprises 0 to 100 levels, wherein the initial level is between 0 and 100 levels. The contour light adjustment method according to claim 1, wherein the step (d) further comprises the step of: if Gc=Gp, indicating that the calculated level is the level corresponding to the optimal contour light. The contour light adjustment method of claim 1, wherein the optimal predetermined value is equal to two. A computer system for contour light adjustment, the computer system comprising: an image processing unit for adjusting the contour light of the image measuring machine to an initial level, and filtering the image of the area where the contour light needs to be adjusted and a calculation unit for setting a variable involved in the contour light adjustment process, the variable includes an upper adjacent level Vm of the level Vp corresponding to the optimal contour light, a lower adjacent level Vn, and a current level Vc, and Calculating the level of the best contour light corresponding to the image, comprising: (a) initializing each variable, the variable including the upper adjacent level Vm and the lower adjacent level Vn of the level corresponding to the best contour light, that is, the upper The adjacent level Vm=100, the next adjacent level Vn=1; (b) the level of the contour light is adjusted to Vc=(Vm+Vn)/2; (c) the image at the level Vc and the gray value of the image are obtained. Gc; (d) determining whether the gray value Gc is smaller than the gray value Gp of the image under the optimal contour light; (e) if Gc < Gp, then the level Vc is the next adjacent level, that is, making Vn =Vc, if Gc>Gp, then the level Vc is the upper adjacent level, that is, Vm=Vc; (f) comparing whether the difference between the current upper adjacent level Vm and the lower adjacent level Vn (Vm-Vn) is less than a best predetermined value V0; and (g) if Vm-Vn<V0, indicating the above calculation And the adjusted level is the level corresponding to the best contour light; and (h) if Vm-Vn>=V0, returning to step (b); and the contour light adjusting unit for calculating the level according to the calculating unit The contour light is automatically adjusted. The computer system according to claim 6, wherein the ash of the best contour light image is The degree value may take an intermediate value of 0 to 255, and the level of the contour light includes 0 to 100 levels, wherein the initial level is between 0 and 100 levels. The computer system of claim 6, wherein the variable comprises an upper adjacent level Vm and a lower adjacent level Vn of a level corresponding to the best contour light. The computer system according to claim 8, wherein the calculating unit calculates the level of the best contour light by using an iterative approximation method, and the calculation formula of the iterative approximation method is Vc=(Vm+Vn)/2, wherein Vc refers to the level of the current contour light.