Image position calibration method and image displacement sensor

Abstract

The embodiment of the application provides a kind of image position calibration method and image displacement sensor, by obtaining target instantaneous image;According to the target instantaneous image and the pre-stored position image library, determine the position information corresponding to the target instantaneous image, wherein the pre-stored position image library at least includes instantaneous image and the position information corresponding to the instantaneous image, by a certain length of measuring unit, different position image data is collected according to the required accuracy, and the position information is completed information library establishment, establish position image library, after collecting target instantaneous image, compare target instantaneous image with the image stored in position image library, in this way, according to the position information of the image in position image library, determine the target instantaneous image collected, so as to quickly calibrate image position, avoid the error generated by long distance test, improve the accuracy of measurement.

Description

Technical Field

[0001] This application relates to the field of image processing technology, and more specifically, to an image position calibration method and an image displacement sensor. Background Technology

[0002] With the widespread use of CNC machine tools in the machining field, the precision requirements for products processed by CNC machine tools are constantly increasing. The grating ruler is a product that assists in improving the tool feed accuracy of CNC machine tools. It is often used in the closed-loop servo system of CNC machine tools and can be used to detect linear or angular displacement. Currently, grating rulers are used to measure the distance moved. However, as the measurement distance increases, the error also increases. How to test long distances with small measurement errors is an urgent problem to be solved. Summary of the Invention

[0003] The purpose of some embodiments of this application is to provide an image position calibration method and an image displacement sensor. Through the technical solutions of the embodiments of this application, a target instantaneous image is acquired; based on the target instantaneous image and a pre-stored position image library, position information corresponding to the target instantaneous image is determined. The pre-stored position image library includes at least instantaneous images and position information corresponding to the instantaneous images. This is achieved by using a measurement unit of a certain length to collect image data at different positions according to the required accuracy, and establishing a position information library. After acquiring the target instantaneous image, it is compared with the images stored in the position image library. Thus, based on the position information of the images in the position image library, the acquired target instantaneous image is determined. This allows for rapid image position calibration, avoids errors caused by long-distance testing, and improves measurement accuracy.

[0004] Firstly, some embodiments of this application provide a method for calibrating image positions, including:

[0005] Acquire a snapshot of the target.

[0006] Based on the instantaneous image of the target and a pre-stored location image library, the location information corresponding to the instantaneous image of the target is determined, wherein the pre-stored location image library includes at least instantaneous images and location information corresponding to the instantaneous images.

[0007] Some embodiments of this application involve using a measuring unit of a certain length to collect image data at different positions according to the required accuracy, and establishing a location information database. After collecting a target instant image, the target instant image is compared with the images stored in the location image database. In this way, the target instant image is determined based on the location information of the images in the location image database. This allows for rapid determination of the image position, avoids errors caused by long-distance testing, and improves measurement accuracy.

[0008] Optionally, the pre-stored location image library is obtained in the following manner:

[0009] Acquire instantaneous images;

[0010] The instantaneous image is decomposed to obtain smaller decomposed images;

[0011] The discrete cosine transform is performed on each of the decomposed small images to obtain discrete cosine transform data corresponding to the decomposed small images.

[0012] The average value of the discrete cosine coefficients is determined based on the discrete cosine transform data corresponding to the decomposed small images;

[0013] The positional information relative to the instantaneous image is determined based on the grayscale value of each pixel in the instantaneous image and the average value of the discrete cosine coefficients.

[0014] The instantaneous image and the corresponding location information are stored in the location image library.

[0015] Some embodiments of this application use the uniqueness of the microstructure of different objects, which have subtle differences from one another, to calibrate the position of the acquired instantaneous image and establish a position image library. The instantaneous image and the corresponding position information are stored in the position image library, so that the position of subsequent images can be calibrated.

[0016] Optionally, determining the average value of the discrete cosine coefficients based on the discrete cosine transform data corresponding to the decomposed small images includes:

[0017] Calculate the sum of the discrete cosine transform data of each pixel in the decomposed small image;

[0018] The average value of the discrete cosine coefficients is determined based on the number of pixels in the decomposed small image and the sum value.

[0019] Some embodiments of this application perform DCT transformation on each image block from left to right and from top to bottom, discarding high-frequency components and retaining low-frequency components, and calculate the average value of DCT coefficients based on the obtained DCT values.

[0020] Optionally, determining the positional information relative to the instantaneous image based on the grayscale value of each pixel of the instantaneous image and the average value of the discrete cosine coefficients includes:

[0021] If the grayscale value of a pixel in the instantaneous image is greater than or equal to the average value of the discrete cosine coefficients, then the pixel of the instantaneous image is set as the first identifier;

[0022] If the grayscale value of a pixel in the instantaneous image is less than the average value of the discrete cosine coefficients, then the pixel of the instantaneous image is set as the second identifier;

[0023] Based on the first identifier and the second identifier, determine the hash value corresponding to the instantaneous image;

[0024] The location information of the instantaneous image is determined based on the hash value corresponding to the instantaneous image.

[0025] In some embodiments of this application, the hash value of each instantaneous image is calculated to determine whether adjacent images are the same image, and the location information of the instantaneous image is identified.

[0026] Optionally, the step of performing discrete cosine transform processing on the decomposed small images to obtain discrete cosine transform data corresponding to the decomposed small images includes:

[0027] The decomposed small images are sequentially subjected to discrete cosine transform processing in order from left to right and from top to bottom to obtain the low-frequency components corresponding to the small images.

[0028] The decomposed small images are quantized and compressed to obtain compressed images;

[0029] The compressed image is subjected to inverse discrete cosine transform to obtain the instantaneous image.

[0030] Some embodiments of this application quantize and compress the remaining image blocks, and the image composed of the compressed data greatly reduces the storage space; during decompression, DCT inverse transformation (IDCT) is performed on each image block, and then a complete image is reconstructed, which can reduce the storage space.

[0031] Optionally, the method further includes:

[0032] If the number of identical values ​​in the hash values ​​of the first instantaneous image and the second instantaneous image is greater than or equal to a preset value, the first instantaneous image and the second instantaneous image are determined to be the same instantaneous image.

[0033] Some embodiments of this application determine the difference between two adjacent frames, utilize a perceptual hash algorithm, and perform a re-examination of the initial detection results to improve the accuracy of image recognition.

[0034] Secondly, some embodiments of this application provide an image displacement sensor, including: a measurement unit, a microscopic imaging unit, a transmission unit, and a control unit. The measurement unit and the microscopic imaging unit are connected to the control unit through the transmission unit, wherein the control unit is used to execute the image position calibration method described in the first aspect.

[0035] This application utilizes the uniqueness of the microstructure of different objects, which have subtle differences from one another, to calibrate the acquired position images and establish a position image library. After acquiring instantaneous images, the instantaneous images are compared with the image library to determine the position information. The difference between two adjacent frames is judged, and a perceptual hash algorithm is used to re-examine the initial detection results. Based on the above principles, an image displacement sensor is developed.

[0036] Optionally, the microscopic imaging unit is a camera device, which is used to take pictures at the shooting position.

[0037] Optionally, the control unit includes at least a control board, and the control board includes at least a microcontroller and a memory.

[0038] Optionally, the transmission unit includes at least a transmission line, and the transmission unit is used to send the image acquired by the microscopic imaging unit to the control unit.

[0039] This application utilizes the uniqueness of the microstructure of different objects, which have subtle differences from one another, to calibrate the acquired position images and establish a position image library. After acquiring instantaneous images, the instantaneous images are compared with the image library to determine the position information. The difference between two adjacent frames is judged, and a perceptual hash algorithm is used to re-examine the initial detection results. Based on the above principles, an image displacement sensor is developed. Attached Figure Description

[0040] To more clearly illustrate the technical solutions of some embodiments of this application, the accompanying drawings used in some embodiments of this application will be briefly described below. It should be understood that the following drawings only show some embodiments of this application and should not be regarded as a limitation of the scope. For those skilled in the art, other related drawings can be obtained based on these drawings without creative effort.

[0041] Figure 1 A schematic flowchart illustrating an image location calibration method provided in an embodiment of this application;

[0042] Figure 2 This is a schematic diagram of the structure of the image position calibration system provided in the embodiments of this application;

[0043] Figure 3 This is a schematic diagram of the structure of another image position calibration system provided in an embodiment of this application. Detailed Implementation

[0044] The technical solutions of some embodiments of this application will now be described with reference to the accompanying drawings.

[0045] It should be noted that similar reference numerals and letters in the following figures indicate similar items; therefore, once an item is defined in one figure, it does not need to be further defined and explained in subsequent figures. Furthermore, in the description of this application, terms such as "first," "second," etc., are used only to distinguish descriptions and should not be construed as indicating or implying relative importance.

[0046] With the widespread use of CNC machine tools in the machining field, the precision requirements for products processed by CNC machine tools are constantly increasing. Grating rulers are a product used to assist in improving the tool path accuracy of CNC machine tools. They are frequently used in closed-loop servo systems of CNC machine tools and can be used for linear or angular displacement detection. Currently, grating rulers are used to measure the distance moved. However, as the measurement distance increases, the error also increases. How to test long distances with minimal measurement error is a pressing issue. Therefore, some embodiments of this application provide an image position calibration method, which includes acquiring a target instantaneous image; and calibrating the target instantaneous image with a pre-stored... A pre-stored location image library is used to determine the location information corresponding to the instantaneous image of the target. The pre-stored location image library includes at least the instantaneous image and the location information corresponding to the instantaneous image. By collecting image data at different locations with a certain length of measurement unit according to the required accuracy and calibrating the location information, a complete information library is established. After collecting the instantaneous image of the target, the instantaneous image of the target is compared with the images stored in the location image library. In this way, the collected instantaneous image of the target is determined based on the location information of the images in the location image library. This allows for rapid determination of the image location, avoids errors caused by long-distance testing, and improves the accuracy of measurement.

[0047] like Figure 1 As shown, embodiments of this application provide a method for calibrating image positions, the method comprising:

[0048] S101. Acquire a momentary image of the target;

[0049] Specifically, the embodiments of this application employ the following... Figure 2 The image position calibration system shown acquires a target instantaneous image through the microscopic imaging unit 2 and sends the acquired target instantaneous image to the control unit 3, which then acquires the target instantaneous image.

[0050] S102. Based on the instantaneous image of the target and the pre-stored location image library, determine the location information corresponding to the instantaneous image of the target, wherein the pre-stored location image library includes at least the instantaneous image and the location information corresponding to the instantaneous image.

[0051] Specifically, a location image library is pre-stored in the control unit. When a target instantaneous image is acquired, the acquired target instantaneous image is compared with the instantaneous image in the location image library. Then, the location information of the target instantaneous image is determined based on the location information of the instantaneous image in the location image library.

[0052] Some embodiments of this application involve using a measurement unit 1 of a certain length to collect image data at different positions according to the required accuracy, and establishing a position information database. After collecting the instantaneous image of the target, the instantaneous image of the target is compared with the images stored in the position image database. In this way, the instantaneous image of the target is determined based on the position information of the images in the position image database. This allows for rapid determination of the image position, avoids errors caused by long-distance testing, and improves the accuracy of measurement.

[0053] Another embodiment of this application further supplements the description of the image position calibration method provided in the above embodiments.

[0054] Optionally, a pre-stored location image library is obtained as follows:

[0055] Acquire instantaneous images;

[0056] The instantaneous image is decomposed to obtain smaller decomposed images;

[0057] The discrete cosine transform is performed on each of the decomposed small images to obtain the discrete cosine transform data corresponding to the decomposed small images.

[0058] The average value of the discrete cosine coefficients is determined based on the discrete cosine transform data corresponding to the decomposed small images;

[0059] The positional information of the instantaneous image is determined based on the gray value of each pixel and the average value of the discrete cosine coefficients.

[0060] The instantaneous images and their corresponding location information are stored in a location image library.

[0061] Some embodiments of this application use the uniqueness of the microstructure of different objects, which have subtle differences from one another, to calibrate the position of the acquired instantaneous image and establish a position image library. The instantaneous image and the corresponding position information are stored in the position image library, so that the position of subsequent images can be calibrated.

[0062] Optionally, the average value of the discrete cosine coefficients is determined based on the discrete cosine transform data corresponding to the decomposed small images, including:

[0063] Calculate the sum of the discrete cosine transform data of each pixel in the decomposed small image;

[0064] The average value of the discrete cosine coefficients is determined based on the number and value of pixels in the decomposed small images.

[0065] Some embodiments of this application perform DCT transformation on each image block from left to right and from top to bottom, discarding high-frequency components and retaining low-frequency components, and calculate the average value of DCT coefficients based on the obtained DCT values.

[0066] Optionally, the positional information relative to the instantaneous image is determined based on the grayscale value of each pixel and the average discrete cosine coefficient, including:

[0067] If the grayscale value of a pixel in the instantaneous image is greater than or equal to the average value of the discrete cosine coefficients, then the pixel of the instantaneous image is set as the first identifier;

[0068] If the grayscale value of a pixel in a momentary image is less than the average value of the discrete cosine coefficients, then the pixel in the momentary image is set as the second identifier;

[0069] Based on the first identifier and the second identifier, determine the hash value corresponding to the instantaneous image;

[0070] The location information of the instantaneous image is determined based on the hash value corresponding to the instantaneous image.

[0071] In some embodiments of this application, the hash value of each instantaneous image is calculated to determine whether adjacent images are the same image, and the location information of the instantaneous image is identified.

[0072] Optionally, discrete cosine transform (DCT) is performed on each of the decomposed small images to obtain DCT data corresponding to the decomposed small images, including:

[0073] The decomposed small images are processed sequentially from left to right and from top to bottom to obtain the low-frequency components corresponding to the small images.

[0074] The decomposed smaller images are quantized and compressed to obtain the compressed image;

[0075] The compressed image is processed by inverse discrete cosine transform to obtain the instantaneous image.

[0076] Some embodiments of this application quantize and compress the remaining image blocks, and the image composed of the compressed data greatly reduces the storage space; during decompression, DCT inverse transformation (IDCT) is performed on each image block, and then a complete image is reconstructed, which can reduce the storage space.

[0077] Optionally, the method further includes:

[0078] If the number of identical values ​​in the hash values ​​of the first instantaneous image and the second instantaneous image is greater than or equal to a preset value, the first instantaneous image and the second instantaneous image are determined to be the same instantaneous image.

[0079] Some embodiments of this application determine the difference between two adjacent frames, utilize a perceptual hash algorithm, and perform a re-examination of the initial detection results to improve the accuracy of image recognition.

[0080] Specifically, in this embodiment of the application, a location image library is pre-established, including:

[0081] 1. Acquire instantaneous images using microscopic imaging techniques and record the positional information of those instantaneous images;

[0082] 2. Positioning of instantaneous images is determined using different location information;

[0083] 3. Establish a location image database based on instantaneous images and their location information;

[0084] The steps to establish a location image library are as follows:

[0085] 1) Image acquisition is performed during the movement. For example, if the accuracy is 1µm, then one image is acquired for every 1µm, which is an instantaneous image.

[0086] 2) Decompose the instantaneous image into 8*8 image blocks;

[0087] 3) Convert the RGB system representing pixels to the YUV system;

[0088] 4) Then, from left to right and from top to bottom, perform DCT (Discrete Cosine Transform) on each image block, i.e., the decomposed small image, discarding high-frequency components and retaining low-frequency components;

[0089] 5) The remaining image blocks are quantized and compressed, and the image composed of the compressed data greatly reduces the storage space;

[0090] 6) During decompression, inverse DCT (IDCT) is performed on each image block, and then a complete image is reconstructed;

[0091] 7) Calculate the average value of the DCT coefficients.

[0092] 8) Calculate the hash value, which is to compare the gray level of each pixel with the average value of the DCT coefficients. If it is greater than or equal to the average value, it is recorded as 1, and if it is less than the average value, it is recorded as 0. The results are combined to form a 64-bit binary integer, which is the hash value of the instantaneous image. The location information is marked according to the hash value.

[0093] 9) Establish a location image library based on location information and instantaneous images.

[0094] It should be noted that each of the implementable methods in this embodiment can be implemented individually or in any combination without conflict. This application does not limit this.

[0095] Another embodiment of this application provides an image displacement sensor, including: a measurement unit 1, a microscopic imaging unit 2, a transmission unit, and a control unit 3. The measurement unit and the microscopic imaging unit are connected to the control unit through the transmission unit, wherein the control unit is used to execute the above-described image position calibration method.

[0096] This application utilizes the uniqueness of the microstructure of different objects, which have subtle differences from one another, to calibrate the acquired position images and establish a position image library. After acquiring instantaneous images, the instantaneous images are compared with the image library to determine the position information. The difference between two adjacent frames is judged, and a perceptual hash algorithm is used to re-examine the initial detection results. Based on the above principles, an image displacement sensor is developed.

[0097] Optionally, the microscopic imaging unit is a camera device used to take pictures at the shooting position.

[0098] Optionally, the control unit includes at least a control board, and the control board includes at least a microcontroller and a memory.

[0099] Optionally, the transmission unit includes at least a transmission line, and the transmission unit is used to send the image acquired by the microscopic imaging unit to the control unit.

[0100] like Figure 2 and Figure 3 As shown, the image displacement sensor provided in this application embodiment includes: a measurement unit 1, a microscopic imaging unit 2, a transmission line, and a control unit. The measurement unit 1 is a scale. The measurement unit can be an unprocessed grating scale body. The unprocessed grating scale body can directly compare position information to achieve accurate position feedback. The measurement unit can also be a grating scale body with processed stripes. Since the processing of the grating scale body will affect the accuracy of the grating scale sensor, that is, the accuracy of the grating scale body, the accuracy of the grating scale body can be adjusted to improve the positioning accuracy of the grating scale body.

[0101] The microscopic imaging unit 2 is a camera or camera, and the control unit is a control board;

[0102] The location information determination method in this application embodiment includes:

[0103] a) Decompose the image into 8×8 image blocks;

[0104] b) Calculate the DCT, but only take the 8×8 matrix in the top left corner, which represents the lowest frequency in the image;

[0105] c) Calculate the average value, and calculate the average value of the DCT coefficients;

[0106] d) Calculate the hash value by comparing the grayscale of each pixel with the average value of the DCT coefficients. If it is greater than or equal to the average value, it is recorded as 1; if it is less than the average value, it is recorded as 0. The results are combined to form a 64-bit binary integer.

[0107] e) Compare the image hash values. If the number of different data bits is no more than 5, it means that the two images are very similar. If it is greater than 10, it means that they are two different images.

[0108] Obtain the first hash value (i.e., the first binary data) of the first instantaneous image, and obtain the second hash value (i.e., the second binary data) of the second instantaneous image. Compare the first binary data and the second binary data. If the number of identical data is greater than or equal to a preset value, it means that the first instantaneous image and the second instantaneous image are the same image, and store a location information. If the number of identical data is less than the preset value, it means that the first instantaneous image and the second instantaneous image are different images.

[0109] f) After making a judgment, perform a second review, not exceeding 5, and obtain the location information of the marker;

[0110] This application utilizes the uniqueness of the microstructure of different objects, which have subtle differences from one another, to calibrate the acquired position images and establish a position image library. After acquiring instantaneous images, the instantaneous images are compared with the image library to determine the position information. The difference between two adjacent frames is judged, and a perceptual hash algorithm is used to re-examine the initial detection results. Based on the above principles, an image displacement sensor is developed.

[0111] Regarding the apparatus in this embodiment, the specific manner in which each module performs its operations has been described in detail in the embodiments related to the method, and will not be elaborated upon here.

[0112] Regarding the apparatus in this embodiment, the specific manner in which each module performs its operations has been described in detail in the embodiments related to the method, and will not be elaborated upon here.

[0113] It should be noted that each of the implementable methods in this embodiment can be implemented individually or in any combination without conflict. This application does not limit this.

[0114] The above are merely embodiments of this application and are not intended to limit the scope of protection of this application. Various modifications and variations can be made to this application by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of this application should be included within the scope of protection of this application. It should be noted that similar reference numerals and letters in the following figures indicate similar items; therefore, once an item is defined in one figure, it does not need to be further defined and explained in subsequent figures.

[0115] The above description is merely a specific embodiment of this application, but the scope of protection of this application is not limited thereto. Any variations or substitutions that can be easily conceived by those skilled in the art within the scope of the technology disclosed in this application should be included within the scope of protection of this application. Therefore, the scope of protection of this application should be determined by the scope of the claims.

[0116] It should be noted that, in this document, relational terms such as "first" and "second" are used merely to distinguish one entity or operation from another, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Furthermore, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a process, method, article, or apparatus. Without further limitations, an element defined by the phrase "comprising one..." does not exclude the presence of other identical elements in the process, method, article, or apparatus that includes said element.

Claims

1. A method of calibrating the position of an image, characterized by, The method is applied to an image displacement sensor, and the image displacement sensor comprises at least a measurement unit, a microscopic image taking unit, a transmission unit and a control unit, the measurement unit and the microscopic image taking unit are connected with the control unit through the transmission unit, and the method comprises the following steps: The microscopic image taking unit acquires a target instantaneous image according to a precision of 1 um, and sends the acquired target instantaneous image to the control unit; The control unit compares the acquired target instantaneous image with instantaneous images in a pre-stored position image library according to the target instantaneous image and the position image library, and then determines position information of the target instantaneous image according to position information of the instantaneous images in the position image library, wherein the pre-stored position image library comprises at least instantaneous images and position information corresponding to the instantaneous images; The position image library is established by using the uniqueness of microscopic structures of different objects, calibrating acquired position images, collecting image data at different positions according to required precision, and calibrating position information; The pre-stored position image library is obtained by the following method: An instantaneous image is acquired; The instantaneous image is decomposed to obtain a small image after decomposition; Discrete cosine transform processing is performed on the small image after decomposition to obtain discrete cosine transform data corresponding to the small image after decomposition; An average value of discrete cosine coefficients is determined according to the discrete cosine transform data corresponding to the small image after decomposition; Position information corresponding to the instantaneous image is determined according to a gray value of each pixel of the instantaneous image and the average value of the discrete cosine coefficients; The instantaneous image and the position information corresponding to the instantaneous image are saved in the position image library; The average value of the discrete cosine coefficients is determined according to the discrete cosine transform data corresponding to the small image after decomposition, which comprises the following steps: A sum value of discrete cosine transform data of each pixel in the small image after decomposition is calculated; The average value of the discrete cosine coefficients is determined according to the number of pixels in the small image after decomposition and the sum value; The discrete cosine transform processing is performed on the small image after decomposition to obtain discrete cosine transform data corresponding to the small image after decomposition, which comprises the following steps: The small image after decomposition is sequentially subjected to discrete cosine transform processing in a sequence from left to right and from top to bottom to obtain low-frequency components corresponding to the small image; The small image after decomposition is subjected to quantization compression to obtain a compressed image; The compressed image is subjected to inverse discrete cosine transform processing to reconstruct a complete image, and the instantaneous image is obtained.

2. The method of claim 1, wherein The position information corresponding to the instantaneous image is determined according to the gray value of each pixel of the instantaneous image and the average value of the discrete cosine coefficients, which comprises the following steps: If the gray value of the pixel of the instantaneous image is greater than or equal to the average value of the discrete cosine coefficients, the pixel of the instantaneous image is set as a first mark; If the gray value of the pixel of the instantaneous image is less than the average value of the discrete cosine coefficients, the pixel of the instantaneous image is set as a second mark. According to the first identifier and the second identifier, a hash value corresponding to the instantaneous image is determined; According to the hash value corresponding to the instantaneous image, position information corresponding to the instantaneous image is determined.

3. The method of claim 1, wherein The method further comprises: In a case where the number of same values in the hash value of the first instantaneous image and the hash value of the second instantaneous image is greater than or equal to a preset value, the first instantaneous image and the second instantaneous image are determined as the same instantaneous image.

4. An image displacement sensor, characterized by The image displacement sensor at least comprises a measurement unit, a microscopic image capturing unit, a transmission unit and a control unit, the measurement unit and the microscopic image capturing unit are connected with the control unit through the transmission unit, wherein the control unit is used for the image position calibration method as claimed in any one of claims 1-3.

5. The image displacement sensor of claim 4, wherein, The microscopic image capturing unit is a camera device, and the microscopic image capturing unit is used for photographing at a photographing position.

6. The image displacement sensor of claim 4, wherein, The control unit at least comprises a control board, and the control board at least comprises a single-chip microcomputer and a memory.

7. The image displacement sensor of claim 4, wherein, The transmission unit at least comprises a transmission line, and the transmission unit is used for sending the image collected by the microscopic image capturing unit to the control unit.

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