JP2010151712A - Phase difference detection system - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To heighten up to a pixel unit at high speed, phase difference detection accuracy with respect to a processing object. <P>SOLUTION: A plurality of dummy images are extracted among all dummy images acquired in relation to a phase difference from a reference position, and a processing object image is compared with the plurality of dummy images, and one dummy image whose phase is most similar to the processing object image is extracted. Then, a plurality of dummy images whose each phase difference with one dummy image whose phase is most similar to the processing object image is within a fixed range are extracted from among all the dummy images, and one dummy image whose phase is most similar to the processing object image is extracted from among them, and the phase difference with the dummy image is replaced with a pixel numerical value. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention provides a processed object that is required as a pre-process when performing a highly accurate and accurate fixed process at a fixed position on the outer surface of a processed object having various displays such as patterns, characters, and barcodes on the outer surface. The present invention relates to a system for detecting a phase difference (phase angle difference) from a reference position.

  Some beverages are provided to consumers by attaching a straw or other device to the outer surface of the container. In such beverages, when the consumer drinks the beverage in the container, the beverage is peeled off from the container. You can use tools such as straws.

  In the beverage container, various indications such as patterns, characters, barcodes, and the like indicating the type of contents, how to drink and eat the contents, product names, prices, and the like are given on the outer surface. For this reason, it is not preferable that these indications are obscured by the tool attached to the outer surface of the container. Therefore, prior to the process of attaching a device such as a straw to the outer surface of the container with an automatic machine, the phase difference from the reference position of the fixed position (the position where the display is not hidden) on the outer surface of the container is detected, and the detection data Based on this, it is performed that the sticking position of the straw by the automatic machine becomes a fixed position on the outer surface of the container.

  Conventionally, in order to detect a phase difference from a reference position of a fixed position (a position where the display is not hidden) on the outer surface of the container, a bottomed cylindrical container with a predetermined mark on the outer surface is placed on a pedestal, It has been practiced to install mark detection sensors at a plurality of equiangular positions around the pedestal and determine which mark detection sensor has detected the mark on the container (conventional example).

Further, as a preceding example, the alignment mark added to the container is detected by a detection means including a light emitting element and a light receiving element, the output signal of the detection means is amplified and differentiated, and the position of the alignment mark is determined from the differentiated signal. Has been proposed (see, for example, Patent Document 1).
JP-A-6-135425

  However, the above-described conventional example has a problem that it is difficult to increase the phase difference detection accuracy because there is a restriction in reducing the installation interval of the mark detection sensor. In addition, because it is necessary to install the mark detection sensor close to the container, in addition to sanitary problems, it is necessary to detect while cleaning and moving the mark detection sensor up and down, so the detection speed is increased. There was a problem that it was difficult to plan.

  The present invention has been made in view of the above problems, and it is possible to solve the problem of hygiene by eliminating the need to install the mark detection sensor close to the container. An object of the present invention is to provide a phase difference detection system in which measures are taken to increase the number of pixels and make it easy to increase the detection speed.

  The phase difference detection system according to the present invention includes a sample image acquisition step, a primary sample image readout step, a processed product image acquisition step, a primary selection image extraction step, a secondary sample image readout step, and a secondary selection image extraction. A process and a calculation process.

  In the sample image acquisition process, one processed object is selected as a dummy from among a large number of the same processed objects having a pattern pattern or the like displayed on the outer surface, and front images at a plurality of positions in the circumferential direction of the dummy are photographed to obtain a reference position. It is the process of acquiring the dummy image of each location linked | related with the phase difference from. The processed products include bottomed cylindrical containers such as beverage containers and food containers, as well as cuboid containers such as paper packs.

  The primary sample image reading step is a step of extracting a plurality of dummy images having different phase differences from the reference position from all the dummy images acquired in the sample image acquiring step.

  The processed product image acquisition step is a step of acquiring one processed product image by capturing a front image of the processed product.

  The primary selection image extraction step compares the single processed product image acquired in the processed product image acquisition step with a plurality of dummy images extracted in the primary sample image reading step, so that the phase is selected from the dummy images. This is a step of extracting one dummy image that most closely approximates the processed product image.

  The secondary sample image reading step includes a plurality of dummy images in which the phase difference from one dummy image extracted in the primary selection image extraction step is within a certain range from all the dummy images acquired in the sample image acquisition step. This is a step of extracting an image.

  In the secondary selection image extraction step, the processed image is compared with the plurality of dummy images extracted in the secondary sample image reading step, so that the phase of the dummy image is closest to the processed image. This is a step of extracting one dummy image.

  The calculation step is a step of replacing the phase difference between the processed image and the one dummy image extracted in the secondary selection image extraction step with a pixel value.

  According to this invention, through a series of steps from the sample image acquisition step to the calculation step, the phase difference detection accuracy of the processed object is increased to the pixel unit. Further, in each of the above steps, there is no need to install a mark detection sensor as described at the beginning close to the container, so that no sanitary problem occurs.

  In the present invention, the four series of steps of the primary sample image reading step, the primary selected image extracting step, the secondary sample image reading step, and the secondary selected image extracting step are among the many dummy images acquired in the sample image acquiring step. To a dummy image having a phase difference closest to one processed image acquired in the processed image acquisition step. In the present invention, the access means consisting of the above four series of steps is divided into two stages: a primary sample image readout step and a primary selection image extraction step, a secondary sample image readout step and a secondary selection image extraction step. As a result, the phase difference from the reference position for the processed image can be detected at high speed without reducing the phase difference detection accuracy.

  To further explain this point, in the present invention, the greater the number of dummy images acquired in the sample image acquisition step, the higher the phase difference detection accuracy. Therefore, in order to increase the phase difference detection accuracy, it is preferable to acquire as many dummy images as possible in the sample image acquisition process. However, the time required to search all of the dummy images and extract the dummy image having the phase difference that most closely approximates the phase difference of the processed image is the greater the number of dummy images acquired in the sample image acquisition process. become longer.

  Therefore, in the present invention, an image reading process for searching all the dummy images and extracting a dummy image having a phase difference that most closely approximates the phase difference of the processed image is performed by two first and second image reading steps. It is possible to detect the phase difference at a high speed by performing the process separately. That is, as a first stage of image readout, a primary selection image extraction step is performed by comparing a part of phase difference dummy images extracted from all dummy images in the primary sample image readout step with a processed product image. One dummy image whose phase is closest to the processed image is extracted from some of the dummy images having a phase difference. Then, as a second stage of image reading, in the secondary sample image reading process, a plurality of dummy images whose phase difference from one dummy image extracted in the primary selection image extraction process is within a certain range are extracted. Thus, the number of dummy images to be accessed is greatly reduced compared to the number of all dummy images, and one dummy image whose phase is closest to the processed image is extracted from a small number of dummy images. I have to.

  When the process of extracting the dummy image having the phase difference that most closely approximates the phase difference of the processed image is divided into the above-described two-stage image reading process of the first stage and the second stage, the sample image acquisition process is performed. Since it is only necessary to search only a part of the obtained dummy images, the phase difference can be detected at high speed without degrading the phase difference detection accuracy.

  In the present invention, in the sample image acquisition step, a plurality of front images at a plurality of intervals in the circumferential direction of the dummy are acquired as dummy images, and in the primary sample image reading step, the phase difference from the reference position in ascending order or It is desirable to extract a predetermined number of dummy images from all the dummy images arranged in descending order. The plurality of dummy images extracted in the secondary sample image reading step includes the dummy images extracted in the primary sample image reading step, and the phase difference from the reference position is larger than that of the dummy image. It is desirable that the predetermined number of dummy images are arranged in the order of decreasing and increasing. In this way, the mutual phase differences of the plurality of dummy images extracted in the primary sample image reading step are equalized. Therefore, in the process of searching for the plurality of dummy images extracted in the secondary sample image reading step, the same Since the dummy images are not searched redundantly, the time spent for detecting the phase difference is not wasted.

  In the present invention, the rotating pedestal mounted with the dummy in the sample image acquisition step and intermittently rotated, and the front image of the dummy mounted on the rotating pedestal in the sample image acquisition step are stopped. In some cases, a dummy image of each part is acquired as image data by photographing at a fixed position, and a front image of the processed object is captured at the fixed position in the processed object image acquiring step, and the processed object image is converted into image data. And a terminal device for causing the primary sample image readout step, the primary selection image extraction step, the secondary sample image readout step, the secondary selection image extraction step, and the calculation step to be performed. It is desirable to provide.

  As described above, according to the present invention, the phase difference detection accuracy for a processed product is increased to a pixel unit without causing a sanitary problem, and the detection speed can be increased.

  For this reason, it is beneficial to perform processing with an automatic machine in which a tool such as a straw is attached to a predetermined portion of a beverage container having various displays such as a pattern on the outer surface with high accuracy and accuracy. That is, the present invention is useful for eliminating a situation in which the display is obscured by the tool attached to the outer surface of the container by processing with an automatic machine.

  FIG. 1 is a flowchart showing a series of steps adopted in an embodiment of a phase difference detection system according to the present invention. FIG. 2 is a flowchart showing specific processing performed in the series of steps shown in FIG.

  As shown in FIG. 1, in the phase difference detection system of this embodiment, a sample image acquisition step, a primary sample image read step, a processed product image acquisition step, a primary selection image extraction step, and a secondary sample image read step The secondary selection image extraction step and the calculation step are performed in this order.

  In the sample image acquisition process, one processed object is selected as a dummy from among a large number of the same processed objects having a pattern pattern or the like displayed on the outer surface, and front images at a plurality of positions in the circumferential direction of the dummy are photographed to obtain a reference position. It is the process of acquiring the dummy image of each location linked | related with the phase difference from. The processed product includes a bottomed cylindrical container such as a beverage container and a food container and a rectangular parallelepiped container such as a paper pack. Below, a bottomed cylindrical container is demonstrated as an example of a processed material.

  FIG. 3 is an explanatory diagram of a process of acquiring a dummy image at each location associated with a phase difference from the reference position by capturing front images at a plurality of locations in the circumferential direction of the dummy D. In the figure, reference numeral 1 denotes a rotating pedestal that is intermittently driven at a fixed angle, and an arrow R indicates the intermittent rotation direction. One rotation angle θ of the rotary base 1 can be arbitrarily determined, and is set to, for example, 1.8 ° or 1 °. One imaging device 2 (for example, a digital camera having a communication function) protected by a transparent glass 21 is installed at one fixed position around the rotary base 1. In this sample image acquisition step, the imaging device 2 captures the front image of the dummy D mounted on the rotating pedestal 1 at a fixed position when the rotating pedestal 1 is stopped, and associates it with the phase difference from the reference position. This is a means for acquiring dummy images at each location as image data. Therefore, in the system in which the rotation angle θ of the rotation base 1 is set to 1.8 °, 200 dummy images having a phase difference of 1.8 ° can be acquired. Further, in a system in which the rotation angle θ of the rotation base 1 is set to 1 °, 360 dummy images having a phase difference of 1 ° can be acquired. In the figure, if a indicates the reference position, the phase difference A from the reference position a of the dummy image to be acquired is expressed by Expression (1).

  A = θ · N (1)

  In the formula (1), N = 0 or a positive integer of 0 <N <(360 / θ). When N = 0, A indicates the phase difference (A = 0) of the reference position a. Therefore, when the rotary pedestal 1 is stopped, the total number of dummy images taken at a fixed position and associated with the phase difference A from the reference position, that is, all of the dummy images acquired in the sample image acquisition process is obtained. The number (number of sheets) P is expressed by the equation (2).

  P = N + 1 (2)

  As shown in FIG. 2, all (number P) dummy images acquired in the sample image acquisition process are associated with the phase difference from the reference position by the storage means of the terminal device (personal computer) 3 (see FIG. 3). Memorized and registered.

  In FIG. 1, the primary sample image reading step is a step of extracting a plurality of dummy images having different phase differences from the reference position from all the dummy images acquired in the sample image acquiring step. In this embodiment, a predetermined number of dummy images are extracted from all dummy images arranged in order of increasing or decreasing phase difference from the reference position.

  FIG. 4 is an explanatory diagram of the primary sample image reading process. FIG. 4 shows an example in which the number (number) of all dummy images acquired in the sample image acquisition process is 45. The phase difference from the reference position of each of the dummy images D1 to D45 increases toward the arrow X direction and the arrow Y direction. In this example, five dummy images D9, D18, D27, D36, and D45 are extracted from every nine dummy images D1 to D45. As described above, when only the five dummy images D9, D18, D27, D36, and D45 having different phase differences extracted from all the dummy images D1 to D45 are extracted in the primary sample image reading step, all the dummy images are extracted. There is no need to access D1 to D45, and the processing speed is increased accordingly.

  The processed product image acquisition step is a step of acquiring one processed product image by capturing a front image of the processed product. Therefore, the number of processed images for one processed product is one. In this processed product image acquisition step, the dummy D shown in FIG. 3 is replaced with the processed product, and a front image of the processed product is taken by the imaging device 2.

  The primary selection image extraction process shown in FIG. 1 includes five dummy images D9, D18, D27, D36, and D45 obtained by extracting one processed image acquired in the processed image acquisition process in the primary sample image reading process. This is a step of extracting one dummy image whose phase is closest to the processed image from the dummy images D9, D18, D27, D36, and D45 by comparison. As shown in FIG. 2, in this primary selection image extraction step, the five dummy images D9, D18,... Extracted by the comparison means of the terminal device 3 (see FIG. 3) in the processing image and primary sample image reading step. D27, D36, and D45 are compared, and one dummy image whose phase is closest to the processed image, for example, a dummy image D36 (see FIG. 4) is extracted.

  In FIG. 1, in the secondary sample image reading step, the phase difference from one dummy image extracted in the primary selection image extraction step is within a certain range from all the dummy images acquired in the sample image acquisition step. This is a step of extracting a plurality of dummy images. Specifically, if one dummy image D36 shown in FIG. 4 is extracted in the primary selection image extraction step, a plurality of dummy images whose phase difference from the dummy image D36 is within a certain range, that is, In this step, nine dummy images D28 to D35 having a smaller phase difference than the dummy image D36, the dummy image D36, and nine dummy images D37 to D44 having a larger phase difference than the dummy image D36 are extracted. In this way, 19 dummy images D28 to D44 (FIG. 4) in which the phase difference from one dummy image 36 extracted in the primary selection image extraction step is within a certain range in the secondary sample image reading step. By extracting, the number of dummy images to be accessed is greatly reduced compared to the number of all dummy images. Therefore, the phase difference can be detected at high speed without reducing the phase difference detection accuracy.

  In FIG. 1, in the secondary selection image extraction step, the processed image is compared with a plurality of dummy images extracted in the secondary sample image reading step, so that the phase of the processed image is determined from the dummy images. This is a step of extracting one dummy image that most closely approximates. Specifically, in FIG. 2, the processed image and the 19 dummy images D28 to D44 (FIG. 4) extracted in the secondary sample image reading step by the comparison means of the terminal device 3 (see FIG. 3) are obtained. By comparison, one dummy image whose phase is closest to the processed image, for example, a dummy image D32 is extracted.

  The phase difference from the reference position of the dummy image D32 thus extracted becomes a value that is very close to the phase difference from the reference position for the processed image. Therefore, finally, in the calculation step shown in FIG. 1, the phase difference between the processed image and the one dummy image D32 extracted in the secondary selection image extraction step is replaced with a pixel value (FIG. 2). As shown in FIG. 2, this correction process is performed by processing the dummy image D32 and the processed product image by the comparison calculation means. Specifically, this is a process of detecting a gap between the processed image and the dummy image D32 on the outer surface of the container and determining how many pixels are included in the gap.

  In the above embodiment, through a series of steps from the sample image acquisition step to the calculation step, the phase difference detection accuracy of the processed object is increased to the pixel unit. Further, in each of the above steps, a front image of the processed object may be taken by the imaging device 2 installed at a location away from the processed object, so that the mark detection sensor as described at the beginning is installed close to the container. This eliminates the need to do so and does not cause hygiene problems.

  Further, in this embodiment, a series of steps from the primary sample image reading step to the primary selected image extracting step, the secondary sample image reading step, and the secondary selected image extracting step are 45 pieces acquired in the sample image acquiring step. This is a step of accessing the dummy image D32 having the phase difference closest to one processed product image acquired in the processed product image acquiring step from among the dummy images D1 to D45. In this embodiment, this step is divided into two steps, ie, a primary sample image reading step and a primary selection image extraction step, and a secondary sample image reading step and a secondary selection image extraction step. The phase difference from the reference position for the processed image can be detected at high speed without reducing the image quality.

  Of course, the embodiment of the present invention is not limited to the embodiment, and various modifications can be made to the embodiment without departing from the scope of the invention.

It is the flowchart which showed the series of processes employ | adopted by embodiment of this invention. It is the flowchart which showed the specific process performed in the series of processes shown in FIG. It is explanatory drawing of the process of acquiring a dummy image. It is explanatory drawing of a primary sample image reading process.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Rotation base 2 Imaging device 3 Terminal device θ One rotation angle of the rotation base D Dummy

Claims (4)

One processed product is selected as a dummy from a large number of the same processed products having a pattern pattern or the like displayed on the outer surface, and front images of the dummy in a plurality of circumferential directions are photographed and associated with the phase difference from the reference position. A sample image acquisition step of acquiring a dummy image of each location,
A primary sample image reading step for extracting a plurality of dummy images having different phase differences from the reference position from all the dummy images acquired in the sample image acquiring step;
A processed product image acquisition step of acquiring one processed product image by capturing a front image of the processed product;
By comparing one processed image acquired in the processed image acquisition process with a plurality of dummy images extracted in the primary sample image reading process, the phase of the dummy images is most approximate to the processed image. A primary selection image extraction step of extracting one dummy image;
A secondary sample image for extracting a plurality of dummy images whose phase difference with a single dummy image extracted in the primary selection image extraction step is within a certain range from all the dummy images acquired in the sample image acquisition step A reading process;
By comparing the processed image with a plurality of dummy images extracted in the secondary sample image reading step, one dummy image whose phase is closest to the processed image is extracted from the dummy images. Secondary selection image extraction process;
A calculation step of replacing the phase difference between the processed product image and one dummy image extracted in the secondary selection image extraction step with a pixel value;
A phase difference detection system comprising: In the sample image acquisition step, a front image of a plurality of locations at equal intervals in the circumferential direction of the dummy is acquired as a dummy image,
2. The phase difference detection according to claim 1, wherein in the primary sample image reading step, a predetermined number of dummy images are extracted from all dummy images arranged in order of increasing or decreasing phase difference from the reference position. system.   The plurality of dummy images extracted in the secondary sample image reading step includes the dummy images extracted in the primary sample image reading step, and the phase difference from the reference position is smaller than that of the dummy image. The phase difference detection system according to claim 2, wherein the predetermined number of dummy images are arranged in order and increasing order. A rotating pedestal mounted with a dummy in the sample image acquisition process and driven to rotate intermittently;
In the sample image acquiring step, a dummy front image mounted on the rotating pedestal is photographed at a fixed position when the rotating pedestal is stopped, and dummy images at the respective locations are acquired as image data, and the processed product In an image acquisition step, an imaging device that captures a front image of the processed object at the fixed position and acquires the processed image as image data;
A terminal device for causing the primary sample image readout step, the primary selection image extraction step, the secondary sample image readout step, the secondary selection image extraction step, and the calculation step;
The phase difference detection system according to any one of claims 1 to 3, further comprising:

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