JP2018029232A - Imaging apparatus - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an imaging apparatus capable of improving visibility, even when visual examination by machine vision camera is partially performed by person.SOLUTION: An imaging apparatus 100 having an image sensor 101 includes image storage means 108 for storing the image information of multiple preset areas of interest, storage means 107 for storing the coordinate data and rotation information of the areas of interest, sensor control means 102 for controlling the photographing area of the image sensor 101 from partial reading position, position setting means 105 for reading the coordinate data from the storage means 107, and setting the partial reading position, and output control means 109 for outputting an output image, based on the rotation information, and the image information stored in the image storage means 108.SELECTED DRAWING: Figure 1

Description

  The present invention relates to an imaging apparatus. More specifically, the present invention relates to an imaging apparatus having an image sensor.

  In recent years, machine vision cameras equipped with image sensors have become widespread in appearance inspection systems such as factory production lines. Some image sensors have 10 million or more high pixels. Japanese Patent Application Laid-Open No. 2004-228688 discloses a technique for designating a part of all pixels as a region of interest and reading out only the corresponding region of interest in order to shorten the signal readout time of an image sensor with an increased number of pixels.

Japanese Patent No. 3484178

  However, when the part is a small lot, it takes time to set the pattern matching necessary for automatic determination by the machine vision. Therefore, it is necessary for a human to perform a partial inspection. Patent Document 1 does not consider such a case. For example, when a person confirms the attention area, if the top and bottom are displayed upside down, the visibility is lowered and it is difficult to confirm.

  The problem in the present invention will be described more specifically using the subject shown in FIG. In FIG. 12, two printed circuit boards 1205 and 1206 are combined. This is a contrivance for reducing waste of area when the desired printed circuit board is L-shaped because the rigid circuit board that is the basis of the printed circuit board is square. In the present application, two or more printed circuit boards combined in the arrangement as shown in FIG.

  When this assembled substrate is photographed with a machine vision camera and the attention areas 1201, 1202, 1203, and 1204 are inspected, a monitor that has partially read these photographing locations is displayed as shown in FIG.

  Silk characters 1301, 1302, 1303, and 1304 are obtained by cutting out the respective attention areas 1201, 1202, 1203, and 1204. At this time, the silk characters 1301 and 1302 are displayed upside down. Even if the camera is rotated 180 degrees, the silk characters 1303 and 1304 are displayed upside down. When humans check characters in such a state, the visibility is poor and it is difficult to inspect.

  The present invention has been made in view of the above problems, and an object of the present invention is to provide an imaging apparatus capable of improving visibility even when a human performs a partial appearance inspection using a machine vision camera. .

  In order to achieve the above object, the present invention is an imaging apparatus having an image sensor, and stores image information of a plurality of preset attention areas, coordinate data and rotation information of the attention areas. Storage means for storing, sensor control means for controlling the imaging area of the image sensor from a partial readout position, position setting means for reading out coordinate data from the storage means and setting the partial readout position, and the rotation information Output control means for outputting an output image based on the image information stored in the image storage means.

  According to the present invention, it is possible to provide an imaging apparatus capable of improving the visibility even when a human performs a partial appearance inspection using a machine vision camera.

The block diagram which shows the apparatus structure of embodiment which concerns on this invention. FIG. 13 is a full-screen shooting diagram relating to the assembled substrate of FIG. 12. A table summarizing data stored in the memory 107 according to the first embodiment. The figure which illustrates the relationship between the pixel at the time of memorize | storing the whole screen in the image memory 108, and an address. The figure which illustrates the address at the time of memorize | storing in the image memory 108 each pixel of the image which carried out partial reading imaging | photography. The figure which illustrates the output order of the data from the image memory. FIG. 3 is a diagram illustrating a final output image according to the first embodiment. FIG. 6 is a diagram illustrating a problem of a color image sensor according to a second embodiment. The figure which illustrates the solution means of Embodiment 2. 10 is a flowchart illustrating attention area correction processing according to the second embodiment. FIG. 6 is a diagram illustrating a coordinate system according to the second embodiment. The subject explanatory drawing of a prior art example. The subject explanatory drawing of a prior art example.

  Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings. The embodiment described below is an example for realizing the present invention, and should be appropriately modified or changed depending on the configuration and various conditions of the apparatus to which the present invention is applied. It is not limited to the embodiment. Moreover, you may comprise combining suitably one part of each embodiment mentioned later.

(Embodiment 1)
First, Embodiment 1 will be described with reference to FIGS. 1 to 7 and FIGS. In the following description, a designated area that needs to be inspected among imaging areas of the image sensor is referred to as an attention area (region of interest). A method of cutting out and capturing an attention area as shown in FIG. 12, storing predetermined information, and outputting an imaging signal of the attention area is referred to as partial reading. In addition, photographing in the partial reading is referred to as partial reading photographing.

  In this embodiment, the subject is partially read and photographed as a monochrome image, and image information is output in a state where a part of the attention area is rotated.

  With reference to FIG. 1, the overall configuration of the imaging apparatus of each embodiment will be described. The imaging apparatus 100 includes an image sensor 101, a sensor drive control unit 102, an AD conversion unit 103, a partial readout position setting unit 105, a camera control communication unit 106, a memory 107, an image memory 108, an image memory control unit 109, a lens 110, an image A signal output unit 111 is provided. The AD conversion unit 103 may be configured in the image sensor 101.

  The imaging apparatus 100 has an imaging system including an image sensor 101, and imaging processing is performed by the sensor drive control unit 102 and the AD conversion unit 103. The light flux that has passed through the lens 110 forms an image on the image sensor 101 of the imaging apparatus 100. The sensor drive control unit 102 controls accumulation operation and readout operation of the image sensor 101 as sensor control means. An analog imaging signal is output from the image sensor 101. The analog imaging signal is digitally converted by the AD conversion unit 103 and temporarily stored in the image memory 108 as image data. The image memory 108 is an image storage unit that stores image information of a plurality of preset regions of interest.

  The output of the image data stored in the image memory 108 is controlled by an image memory control unit 109 serving as an output control unit. The image memory control unit 109 designates an address with respect to the image memory 108 to retrieve data, and transmits the image data to the image signal output unit 111. The image signal output unit 111 converts the image data into an output video format and outputs the video.

  On the other hand, the camera control communication unit 106 is an interface that receives the setting of the imaging apparatus 100, coordinate data of a region of interest for which partial reading is desired, and rotation information of the region of interest from a PC or an external device. The memory 107 is a storage unit for storing the setting value of the imaging apparatus 100 input by the camera control communication unit 106, the coordinate data of the attention area to be partially read, and the rotation information of the attention area. The partial readout position setting unit 105 is a position setting unit that reads out coordinate data of a region of interest from the memory 107 and sets a partial readout position for the sensor drive control unit 102.

  The sensor drive control unit 102 controls the imaging area of the image sensor 101 so that the image sensor 101 outputs only image information of the attention area. The image memory control unit 109 receives the rotation information of the attention area from the memory 107 and reads the image data from the image memory 108 according to the information. The rotation information of the attention area will be described later.

  Next, a method for partially reading and photographing an object and outputting an image by rotating a part of the attention area will be described.

  FIG. 2 is a full-screen photograph of the assembled board of FIG. On the printed circuit boards 201 and 202 in the screen 205, square attention areas 203 and 204 are present. Coordinates 207, 208, 209, and 210 are the coordinates of the upper left and lower right corners of each region of interest. Each coordinate value starts from the origin 206 and increases as it is placed to the right or below. For example, the coordinate values of the coordinates 207, 208, 209, and 210 are (2000, 50), (2100, 150), (1000, 2000), and (1100, 2100), respectively.

  These coordinate values are stored in the memory 107 through the camera control communication unit 106 in FIG. In the memory 107, upper left coordinates and lower right coordinates can be stored for each region of interest as shown in FIG. The attention area 203 in FIG. 2 is the attention area NO. 1 and the attention area 204 in FIG. Stored as 2.

  Also, the character string displayed in the attention area 203 in FIG. 2 is upside down and needs to be rotated. As one rotation information, 180 degrees is stored. The rotation information of the attention area can be stored in four ways of 0 degree, 90 degrees, 180 degrees, and 270 degrees. Further, the rotation information can be stored so as to be compatible with an error angle in an actual production line.

  Next, the relationship between pixels and addresses when the entire screen is stored in the image memory 108 of FIG. 1 will be described with reference to FIG. In the address map 401 of the image memory 108, the pixel array 402 of the image sensor stores information of one pixel per address. In order to store 4800 pixels for one line, 0 to 4799 addresses are used. Since the image sensor of this case has 3200 lines, 4800 × 3200 = 15,360,000 addresses are prepared to store one screen.

  In the first embodiment, only a total of two attention regions 203 and 204 are cut out. Therefore, the image data from the AD conversion unit 103 is stored in the image memory 108 in the order of reading. As a result, the image memory 108 is stored as shown in FIG.

  Next, with reference to FIG. 5, the address at which each pixel that has undergone partial readout imaging is stored will be described. The image memory control unit 109 determines an address to be called from the image memory 108 based on the coordinate information and the rotation information of the attention area stored in the memory 107.

  Next, the output order of data from the image memory 108 will be described with reference to FIG. The attention area NO. Since 1 is written with information to be inverted 180 degrees, it is read from the image memory in the order shown in FIG. The image memory control unit 109 outputs addresses so that the image memory 108 outputs image data in the order of (1), (2), (3), and (4), and controls the output order of the addresses.

  Needless to say, the output order of the addresses can be changed corresponding to each piece of rotation information of the region of interest.

  Since the first embodiment is a monochrome image, it is not necessary to consider a pixel color arrangement such as a Bayer arrangement. By reading in this way, a part of the attention area is rotated, and as shown in FIG. 7, both of the attention areas 203 and 204 are displayed in a correct state.

  As described above, according to the present embodiment, even when a human performs a visual inspection by a machine vision camera, a part of the attention area is rotated and the top and bottom are displayed in a correct state, thereby enabling visual recognition. It is possible to obtain an imaging apparatus that can improve the performance.

(Embodiment 2)
Next, Embodiment 2 of the present invention will be described with reference to FIGS. In the first embodiment, partial reading in a monochrome image using a monochrome image sensor has been described. On the other hand, in the second embodiment, partial reading in a color image using a color image sensor will be described. In the case of a color image sensor, each pixel is configured as a Bayer array 801 in FIG.

  In that case, if the designated range is simply rotated, a Bayer array different from the original array 801 may be obtained, such as the arrays 802, 803, and 804 after the rotation, depending on conditions. Therefore, if this image data is directly passed to the image signal output unit 111 of FIG. 1, the image signal output unit 111 acquires color information in the original arrangement, so that the color changes and the image cannot be displayed correctly. Arise.

  The difference between the second embodiment and the first embodiment is an improvement of this point. Therefore, in the second embodiment, only the partial readout position setting unit 105 in FIG. 1 will be described, and the description of the other parts will be omitted because it is the same as in the first embodiment.

  The partial reading position setting unit 105 according to the second embodiment has a function of finely correcting the range of the attention area and setting the partial reading position when the coordinate data of the attention area is read from the memory 107. It has been solved.

  The correction method will be described with reference to FIG. In the pixel array 901 of the color image sensor, R is a red pixel, G is a green pixel, and B is a blue pixel. A range 902 surrounded by a broken line is a range of a region of interest read from the memory 107 in FIG. In order not to destroy the arrangement pattern even when the range of the attention area is rotated, the four corners need to be the arrangement pattern of the dot object of the R pixel.

  That is, the range 902 may be corrected to a range as indicated by the range 903. Since the correction is performed on the order of one pixel, the range of the attention area does not change significantly. If the attention area after correction is an array pattern such as the range 903, the array pattern does not change no matter which angle is rotated by 90 degrees, 180 degrees, or 270 degrees, and this affects the subsequent image signal output unit 111. Things will disappear.

  Next, a coordinate system in the attention area correction flow will be described with reference to FIG. In the memory 107 of FIG. 1, two coordinates are stored as the coordinate data of the region of interest. In the coordinate system of FIG. 11, the upper left is the origin (0, 0) and corresponds to the pixel of the image sensor. Pt and Pb are coordinate data of the upper left (Top) and lower right (Bottom) of the attention area, and a range 1101 is the range of the attention area. This attention area is preset from the outside so as to be a square. This is to prevent the shape from changing even when rotated.

  Next, a flow for correcting the Pt and Pb coordinates so that all four corners of these regions of interest become R pixels will be described with reference to FIG.

  In step 1011 of FIG. 10, it is determined whether the pixel at the Pb coordinate is an R pixel. If it is not an R pixel, the process proceeds to Step 1012.

  Next, in step 1012, it is confirmed whether the pixel of Pb coordinate is a B pixel. If the pixel is a B pixel, the process proceeds to step 1013. In the case of the B pixel, since the R pixel is adjacent to the upper left, upper right, lower left, and lower right of the pixel, any one may be changed to the Pb coordinate. However, in order to make the shape of the attention area square after correction, it can only be changed to either the lower right or upper left R pixel.

  Therefore, in step 1013, it is confirmed that the Pb pixel is not the right end or the lower end of the image sensor area. If it is not either end, the process proceeds to step 1014 in order to change to the lower right R pixel.

  Next, in step 1014, 1 is added to the coordinates Xb and Yb of the Pb pixel, respectively, and the lower row and the right column of the attention area are added. If the Pb pixel is at the right end or the lower end of the image sensor area in step 1013, Xb-1 and Yb-1 are performed in step 1015, and the lower row and the right column in the region of interest are deleted. As a result, the correction is made to the R pixel when the pixel of the Pb coordinate is the B pixel.

  Next, in step 1012, if the pixel at the Pb coordinate is not a B pixel, that is, if it is a G pixel, the process proceeds to step 1016. In step 1016, it is determined whether the pixel is a G pixel in the row of R pixels or a G pixel in the row of B pixels. If the Y coordinate Yb of Pb is an even number, it is a row of R pixels. In this case, the process proceeds to step 1017.

  Next, in step 1017, it is determined whether the pixel at the Pb coordinate is the right end of the image sensor. In the Bayer array of the image sensor, since the last row is a row of B pixels, it is not necessary to confirm that the G pixel in the row of R pixels is the lower end. Therefore, if it is determined at step 1017 that it is the right end, Xb-1 is performed at step 1018, and one column on the right side of the region of interest is deleted. Thereby, the pixel of Pb coordinate is changed to R pixel.

  Next, in step 1018, if one column on the right side of the region of interest is deleted, the shape of the region of interest will no longer be square, so in step 1019 Xt-1 is performed and one column is added to the left side of the region of interest.

  Next, when the pixel at the Pb coordinate is not the right end in step 1017, Xb + 1 is performed in step 1020, and one column is added to the right side of the attention area. Thereby, the pixel of Pb coordinate is changed to R pixel. If one column is added to the right side in step 1020, the shape of the attention area is no longer square. Therefore, Xt + 1 is performed in step 1021, and one column is deleted from the left side of the attention area.

  On the other hand, if it is determined in step 1016 that the pixel at the Pb coordinate is a G pixel in the B pixel row, it is determined in step 1022 whether the Pb coordinate is the lower end of the image sensor. Since the pixel at the right end of the row of B pixels is a B pixel in the Bayer array, it is not necessary to confirm that the G pixel in the row of B pixels is the right end.

  Therefore, if it is determined in step 1022 that the lower end is reached, Yb-1 is performed in step 1023, and one line below the attention area is deleted. Thereby, the pixel of Pb coordinate is changed to R pixel. If one line below the attention area is deleted in step 1023, the shape of the attention area is no longer square. Therefore, Yt-1 is performed in step 1024 to add one line above the attention area. If the pixel at the Pb coordinate is not the lower end in step 1022, Yb + 1 is performed in step 1025, and one line is added below the attention area. Thereby, the pixel of Pb coordinate is changed to R pixel.

  Next, if one line is added below the attention area in step 1025, the shape of the attention area is no longer square. Therefore, Yt + 1 is performed in step 1026, and one line above the attention area is deleted. With these processes, even if it is determined in step 1011 that the pixel of the Pb coordinate is not an R pixel, the lower right pixel Pb of the attention area is changed to an R pixel while the attention area remains square. .

  By performing such range correction of the attention area, the upper left coordinate Pt of the attention area is R pixel or B pixel in the judgment step 1027. This is because the pixel of the Pb coordinate is an R pixel and the attention area is a square, which can be either an R pixel or a B pixel in the pixel array of FIG.

  Therefore, if it is determined in step 1027 that the pixel at the Pt coordinate is not an R pixel, it is always a B pixel. In that case, the process moves to step 1028, and the region of interest is expanded to the upper and left sides by performing Xt-1 and Yt-1, and Pt is finely corrected to R pixels. Here, the fact that the pixel of the Pt coordinate is the B pixel is not the left end or the upper end of the image sensor on the Bayer array, and therefore Xt−1 and Yt−1 can be performed without confirming the end.

  By following the above flow, the attention area is corrected to a pattern of R pixels at the four corners, and becomes a pattern arrangement of point objects. As a result, the original color arrangement is always obtained when the attention area is rotated at any angle of 90 degrees, 180 degrees, and 270 degrees, so that the color can be correctly reproduced in the image signal output 111 of FIG. . Since other processes are the same as those in the first embodiment, description thereof is omitted.

  As described above, according to the present embodiment, when a person partially performs an appearance inspection using a machine vision camera including a color image sensor, the top and bottom are displayed in a correct state by rotating a part of the attention area. . Furthermore, it is possible to obtain an imaging device that can improve visibility by reproducing colors correctly.

  As mentioned above, although preferable embodiment of this invention was described, this invention is not limited to these embodiment, A various deformation | transformation and change are possible within the range of the summary.

107 Memory 105 Partial Reading Position Setting Unit 109 Image Memory Control Unit

Claims (3)

An imaging device having an image sensor,
Image storage means for storing image information of a plurality of attention areas set in advance;
Storage means for storing coordinate data and rotation information of the region of interest;
Sensor control means for controlling the imaging region of the image sensor from a partial readout position;
Position setting means for reading coordinate data from the storage means and setting the partial reading position;
Output control means for outputting an output image based on the rotation information and the image information stored in the image storage means;
An imaging apparatus comprising: The output of the image information of the output control means controls the order of reading out the address of the image information corresponding to the rotation information,
The imaging device according to claim 1. The image sensor is a color image sensor whose pixel array is a Bayer array, and
The position setting means has a function of finely correcting the coordinate data and setting the partial readout position.
The imaging device according to claim 2.

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