JPS59211167A - Pattern position detector - Google Patents

Abstract

PURPOSE:To search automatically and quickly a prescribed pattern and to detect the position of said pattern with high accuracy by narrowing the searching range by a subject pattern position obtained from the rough detection and then carrying out the fine detection. CONSTITUTION:A standard pattern (b), for example, having a size with which the peculiar characteristics is secured in the screen of a pattern is used for the rough detection. If the sempling intervals are defined as 6 picture elements in both vertical and horizontal directions, the entire screen is sampled with intervals of 6 picture elements both vertically and horizontally and then fetched to be successively compared with a 2-dimensional segment pattern having the same size as a standard pattern. Thus the coordinate position having the highest coincidence is obtained. In a fine detection mode an attention is given to the ridge line parts of both vertical and horizontal directions of a pattern. Then the position of a ridge line is detected in the direction rectangular to the rigde line. In this case, the sampling interval is set at one picture element and four sampling patterns (a-d) are used.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Application of the Invention] The present invention relates to a position detection device that automatically and quickly searches for a predetermined pattern in a two-dimensional image and detects its position with high accuracy.

[Background of the invention]

A method has already been developed for extracting a specific pattern from images captured by an imaging device such as a television camera, distinguishing it from other patterns and background patterns, and determining its position in the two-dimensional (6) image. The present inventor filed Japanese Patent Application No. 48-21636 (Japanese Unexamined Patent Publication No. 49-11)
No. 1665). This method stores the local pattern of the target as a standard pattern, sequentially compares this standard pattern with the cutout pattern at each position in the video input by the imaging device, and detects the coordinate position that best matches the standard pattern. By doing so, the position of the entire object is detected. In this case, when the size of the cutout pattern in the video is fixed depending on the device, the following problem occurs.

Figure 1A shows an example of an image obtained from an imaging device. Using the standard pattern shown at the beginning of the figure from image 1, a ``5'' pattern 3 on object 2 is detected. The position of the entire object 2 is detected. At this time, if the mouth pattern consists of, for example, 10 x 10 sample points, in order to detect this pattern, the image plane of A will be searched at a sampling interval corresponding to 1/10 of the pattern mouth both vertically and horizontally. , so the detection accuracy (7) is approximately the same as this sampling interval.

In order to further increase the detection accuracy, if the sampling interval is further reduced to 1/3, for example, 1 of the pattern openings
/3, which is made up of the same 10×10 sample points, is set as a standard pattern, and the entire screen is searched.

However, if we use a small part on the target as the standard pattern, it will match the standard pattern at positions 4-2, 4-3, etc. in addition to the correct position 4-1, so it will definitely be 4-1.
It is difficult to detect the location of This is because the pattern has no specificity as a pattern.

In this case, it would be difficult to simply reduce the sampling interval to 173 by using the pattern opening as the standard pattern in order to improve the detection accuracy, as this would require an extremely large increase in the size of the detection device, such as the memory capacity. .

Generally, it cannot be expected that there will be a pattern on the object that is sufficiently small and has specificity in the image, and there are cases where the addition of such a pattern (8) is not allowed. Other than this point, the problem with this method is that the detection accuracy is determined by the size of the local standard pattern on the target, and the accuracy may be insufficient depending on the application.

[Purpose of the invention]

SUMMARY OF THE INVENTION An object of the present invention is to provide a simple pattern position detection device with a suitable configuration for solving the above problems.

[Summary of the invention]

In order to achieve the above object, the present invention provides a device that performs coarse detection and fine detection by changing the sampling interval, and further narrows the search range based on the target pattern position obtained as a result of coarse detection to perform fine detection. did.

[Embodiments of the invention]

Hereinafter, before a detailed description of the invention, matters necessary for understanding embodiments of the invention will be schematically explained.

For purposes of explanation, an image input device that performs rask-like scanning, such as a television camera, will be considered as an imaging device. This converts video (9) information arranged in space into signals arranged in time, that is, signals that are sent out in series. In this case, sampling on the video is replaced with temporal sampling of the video signal. Here, there are two methods for changing the sampling interval on the video.

The first method is to fix the scanning period and sampling time interval and change the scanning width of the imaging device. In other words, if Fig. 2A is the standard scanning line, -
For example, if the horizontal scan width is reduced by 1/2 and the vertical scan width is reduced by 1/3, the scan line will appear at the mouth for the same image plane, and the spatial sampling interval will therefore change. It turns out. This method can be implemented by controlling the amplitude of the deflection signal of the imaging device. It is easy to change the amplification factors independently of each other for horizontal deflection and vertical deflection, and it is also possible to switch them electronically at high speed. However, due to the characteristics of the imaging device, changing the scanning line in this way may change the characteristics of the video signal, and doing so requires modification of the imaging device (10). This is not a method that can be used.

A second method of changing the sampling interval is to fix the scanning period and deflection amplitude of the imaging device and change the temporal sampling interval of the video signal. Among the base items shown in FIG. 3A, the horizontal lines directly indicate scanning lines, and the vertical lines are drawn at intervals equal to the scanning line spacing. In this case, the intersections of vertical lines and horizontal lines, ie, grid points, are picture elements that are the basis of sampling points when sampling and processing an image. Figure A shows an example of a standard pattern consisting of 4×4 picture elements marked with 0. On the other hand, the drawing shows the sampling points when the horizontal sampling interval is tripled and the vertical sampling interval is doubled, as the intersection of thick vertical lines and horizontal lines, and also uses a 4x4 standard This shows the size of the pattern.

By switching the sampling interval in this manner, even if the number of sampled picture elements constituting the standard pattern is constant, the size of the standard pattern can be appropriately selected.

In the following embodiments, a standard pattern of a size that guarantees the specificity of the pattern in the screen is used in rough detection. In the example of the object shown in Figure 1A-2, the standard pattern of the size shown in the mouth has a specificity.

Assuming that the sampling interval at this time is 6 pixels both vertically and horizontally, the entire screen is sampled and captured at intervals of 6 pixels both vertically and horizontally, and the standard pattern and the two-dimensional cutout pattern of the same size are sequentially compared. , find the coordinate position with the best match. The position obtained in this way includes an error of up to one sampling interval, that is, up to 6 pixels,
In order to obtain a more precise position, precision detection is next performed.

Precise detection is performed by focusing on the ridgeline portions of the pattern in both the horizontal and vertical directions and detecting the position of the ridgeline in a direction perpendicular to the ridgeline. At this time, the sampling interval is one picture element, and four standard patterns shown in FIG. 4 are used. In this case, although the standard pattern has no specificity, the search range is limited using the results obtained by rough detection (12), so no wrong position will be found.

FIG. 5 shows the search range in precise detection. That is, the thick solid lines 5-1.5" 2.5-3.5-4 represent the standard putters 242 (b) and (c) in FIG. 4, respectively.

The rectangle shown with a broken line shows the range of the lower right point shown in each standard pattern of the cutting pattern to be compared with the second one.
The search range of the corresponding cutout pattern is shown. In this case, in coarse detection, the search is performed over the entire screen, while in fine detection, it is only necessary to perform the search in a linear range perpendicular to the ridgeline. Note that the length is at least twice the sampling interval of rough detection, and may be extended to about three times. Note that the rectangle drawn with a broken line in the upper left of the figure indicates the size of the standard pattern.

If rough detection is performed correctly, there is bound to be a part within that range that almost matches the standard pattern, and the degree of matching shows a sharp peak within that range, so at least the sampling interval, that is, approximately one pixel, is guaranteed. The position of the ridgeline can be detected with an accuracy of (13). In this case, even if the ridgeline has some irregularities as shown in FIG. 6, it is possible to detect the average boundary.

If you want to detect a pattern like the one in Figure 7 A, which has no vertical or horizontal ridge lines, prepare the pattern shown in Figure 7 A as a standard pattern for fine detection, and then create the corresponding cutting pattern for fine detection. The two-dimensional subdivision 7-1.7-2 may be used as the search range for the lower right point. If a standard pattern like the one shown in this example is used, the degree of coincidence shows sharp peaks in both the horizontal and vertical directions, so that the necessary positioning can be performed.

Hereinafter, the present invention will be explained in detail with reference to Examples.

FIG. 8 is a block diagram showing an example of the overall configuration of a detection device according to the detection method of the present invention. 11 is a circuit that generates a basic clock, a scanning point coordinate signal 11', and horizontal and vertical synchronization signals if necessary; 12 is a circuit that sends out timing signals necessary for each part according to a specified sampling interval and search range; It is. The signal obtained from the image input device 13 is (14) converted into a black and white binary code 30 by the binarization circuit 14, and thereafter treated as a digital signal.

Reference numeral 15 denotes a video memory that stores two-dimensional images, and stores images corresponding to n-1 scanning lines while sequentially shifting them. Reference numeral 16 denotes a two-dimensional local extraction section of the image consisting of n shift registers of length n'. 17 is also a register for temporarily storing a standard pattern of nXn' points, and the contents of the registers 16 and 17 are compared for each corresponding point by a matching circuit 18 to determine the degree of mismatch between the patterns.

The minimum value detection circuit 19 observes the degree of mismatch, and when a value smaller than the held value appears, it replaces the held value with the value that appears, and also takes in the scanning point coordinates at that time into the register 20. In this way, the value held when the specified range has been scanned remains the minimum value, and the register 20 contains the coordinates of the scanning point at that time.

Reference numeral 21 denotes a calculation circuit that calculates coordinates, provides the pattern search range and sampling interval to the timing signal generation circuit 12, and outputs a signal (15) 21' indicating the detection result of the target position.

Reference numeral 22 denotes a memory for storing as many standard patterns as necessary to be set in the register 17. The motion control unit 23 issues operation commands to each part of the device in order, and upon receiving the search end signal 24, performs sequence control for proceeding to the next stage. In addition, the part indicated by 25, that is, 21 to 2
It is easy to replace the arithmetic processing unit consisting of 3 with a general purpose arithmetic processing unit such as an electronic computer, which increases the flexibility of the entire device. Each part will be explained below.

FIG. 9 shows the configuration of the video memory 15 and the local extraction section 16. Here, the video memory 15 includes n-1 shift registers 31-1, 31-2, . .......

31-n-1 are connected in cascade. The input of the first shift register 31-1 is the binarization circuit 14 in FIG.
This signal is the output 30 of the local extraction unit 1.
6 is input 32-1. Note that the outputs of each shift register 32-2, 32-3. ...*32-n is also input to the local cutting section 16.

(16) Each shift register 31-1, 31-2...

3l-n-1 has a length enough to contain information for one scanning line, so each signal 32-1.32-2°...
, 32-n have information of vertically arranged picture elements in the image.The 0 local extraction unit 16 has n shift registers 33-1, 33-2, .・・・・・・
- Consists of 33-n. These shift registers each receive signals 32-1, 32-2 .・・・・・・32-
n are added as serial inputs and send each parallel output 34 to matching circuit 18.

For the shift registers coupled in this manner, the sampling interval is controlled by clock signals 35, 36. That is, in order to control the sampling interval in the vertical direction to m, both the shift registers 31 and 33 need to use the shift clocks 35 and 3 only every m-th scanning line.
All you have to do is roll a 6.

In this case, the shift register 31 is supplied with a clock 35 for each pixel without sampling.

Furthermore, in order to control the sampling interval in the horizontal direction of the local cut-out portion and set it to m', the shift clock (17) 36 is applied only to each m' picture element.

In this way, the value that was input at the moment of the shift operation is captured, and the values at other times are not captured. For this reason, sampling is performed at the entrance of the shift register 33, and images captured at sampling intervals of m in the vertical direction and m' in the horizontal direction appear one after another in the local cutout section 16.

FIG. 10 shows the configuration of the matching circuit 18, in which n shift registers 33-1, 33-2.
. . . each n' parallel output 34 from 33-n,
An exclusive OR operator 38 sends out a mismatch signal 39 for each set of signals corresponding to the nXn' outputs 37 of the standard pattern temporary storage register 17. In this case, the degree of mismatch of the entire pattern is expressed by the number of '1n' out of nXn' signals 39. Next, the output of each current circuit 40 is turned on and off by the signal 39, and the currents are added by the adding circuit 41, thereby generating a voltage 4 indicating the degree of mismatch corresponding to the number of current source circuits that are turned on.
You can get 2.

(18) In FIG. 10, the adder circuit 41 is constructed from an analog arithmetic circuit, but it can also be constructed from an adder with a 1-bit nXn' input. In this case, the circuit is a multi-stage circuit, with the first stage consisting of a 1-bit 3-manpower adder to obtain a 2-bit output, and the second stage consisting of a 2-bit input adder that performs the same operation as the first stage. Collect the results, proceed through the stages in the same way, and finally obtain the sum of all initial stage inputs, that is, II
The number of 17H can be obtained as a binary number.

FIG. 11 shows the configuration of the minimum value detection circuit 19.

The initial value setter 43 is for setting a large value in the holding circuit 44 as an initial value. When the standard pattern and search range for matching are specified,
The switching device 45 is switched to the initial value side by the timing signal 46, and the holding circuit 44 is switched through the OR operator 47.
The input gate is opened and the initial value from the initial value setter 43 is set.

Next, the switch 45 is returned to the signal 42 side, and the comparator 48 compares the signal 42 (19) indicating the degree of mismatch found momentarily within the search range with the value held in the holding circuit 44. When it is detected that the new value of the mismatch voltage signal 42 is smaller, the new value is gated by the logic integrator 50 using the sampling clock 49, the input gate of the holding circuit 44 is opened through the OR operator 47, and the mismatch voltage Take in the new value of signal 42.

The output 19' of the AND operator 50 also opens the input gate of the register 20, as shown in FIG. 8, and takes in the X and Y coordinates of the scanning point at that time. In this way, when scanning of the search range is completed, the minimum value remains in the holding circuit 44, and the XY coordinates at the time when the minimum value occurs remain in the register 20.

FIG. 13 shows the detailed configuration of the scanning point coordinate and synchronization signal generation circuit 11 and the timing signal generator 12. First, the X coordinate counter 53 is advanced by the output clock 52 of the oscillator 51. The period of the counter 53 is set in a constant setter 54, and when the minus number setting circuit 55 detects that the counter 53 has reached the period (20), the counter 53 is reset.

In this way, the counter 53 repeatedly counts at a predetermined period.

The output 56 of the coincidence detection circuit 55 is applied as a clock to the Y coordinate counter 57, and the counter 57 repeatedly counts at a predetermined period by a combination of a constant setter 58 that provides a period and a coincidence detection circuit 59. Horizontal sync signal generator 6
The zero and vertical synchronization signal generators 61 detect that the contents of the X and Y coordinate counters 53 and 57 have reached predetermined values, respectively, and send out signals having a constant timing and width.

Next, a circuit for limiting the search range in the timing signal generation circuit 12 will be described.

62 and 63 are registers that hold the X coordinates of the left end and right end of the search range, respectively, and the values are given by the arithmetic processing unit 25 in FIG. First, a match between the contents of the X-coordinate counter 53 and 62.63 is detected by the minus number bases 64 and 65, and the flip-flop 66 is set and reset for each (21). Therefore, flip-flop 66 is turned on only when the X coordinate is within the specified range. Similarly, for the Y coordinate, the flip-flop 71 is set and reset by the registers 67, 69 and 69, 70 that give the upper and lower ends, and a signal that is turned on only within the specified range is created.

Next, a sampling interval control circuit will be described. 7
2 is a counter that operates with the same clock 52 as the X coordinate counter 53 in the circuit 11, and its contents are stored in the register 73.
The coincidence detector 74 detects that the period held by the content matches the content.
At that point, the register 73 is reset to return the contents to zero.

In this way, the counter 72 repeatedly counts at the period held by the register 73.

75 detects that the content of the counter 72 is zero, and the output is turned on for only one clock time in one cycle.

Similarly, in the Y direction, a counter 76, a period register 77, a minus number unit 78 . The zero detector 79 produces a signal that turns on only one horizontal scanning line in one period.

(22) Reference numerals 80 to 82 are AND operating units that generate necessary timing signals. That is, the clock 80 outputs the clock 52 gated for one horizontal scanning line at each designated sampling interval in the Y direction, and uses this as the shift clock 35 of the video memory 15. 81 further outputs a clock sampled in the X direction, and uses this as the shift clock 36 of the local extraction section. 82 creates a clock by further limiting the shift clock 36 within the search range in the X and Y directions, and uses it as the clock 49 of the minimum value detection circuit 19. Further, the output of the coincidence detector 70 at the lower end of the search range is used as a signal 24 to notify the processing unit that scanning of the search range has been completed.

FIG. 13 is a block diagram showing an example of the configuration of the calculation circuit, that is, the coordinate calculation processing section 21 in FIG. 8.

In addition, Fig. 14 is an explanatory diagram showing how to switch the standard pattern and search range as the scanning progresses, with the progress direction of screen scanning facing down. 23) are shown consecutively. In both figures above, rough recognition is first performed. Therefore, the operation control unit 23 switches the selection circuit 91 to send out a signal indicating the search range for rough detection. This search range is often taken as the entire screen, and when using the standard pattern A in Figure 14 as the standard pattern, a
The area indicated by the diagonal line. When the scanning progresses and two points are reached, the search ends, and the i point has a mismatch, the degree of match is the minimum, and its coordinates are sent as a signal 20'. This value is stored in the register 93.

Next, the selection circuit 91 is switched and the process moves to fine detection, and 14
Using the standard patterns B, C, D, and E shown in the figure, matching is performed in the linear search ranges shown by s, c, d, and e in FIG. 14, respectively. Since this search range has a fixed relative positional relationship to the i point obtained as a result of rough detection, the value stored in the register 94 for each standard pattern is retrieved by switching the selection circuit 91', and the adder 95 As a result, the position is added to the position of the rough detection result held in the register 93, and the result is sent out through the selection circuit 91. b.

The search range of c, d, and e reaches point q+rySyt (24
), the search ends, and a search end signal 24 is applied from the timing generation circuit 12 to the operation control section 23 as shown in FIG.

Here, it is assumed that with respect to search pattern B, the degree of mismatch is the smallest in portion j. Since there is a certain relative positional relationship between part j and the position n that is to be finally determined, the value stored in the register 96 for each standard pattern is taken out by switching the selection circuit 97, and the value is added by the adder 98. Add the position coordinates of the matching results and store them in the corresponding parts of the register 99. When the matching for the four standard patterns B-H is completed, the X coordinates of the register 99 corresponding to the standard patterns B and E are added. The adder 100-1 adds the signals and removes the least significant bit to obtain the average of both. Similarly, from the results for standard patterns C and D, an adder 100-2 obtains the average of the X coordinates. This output of 100-1°100-2 is the coordinate of the n point to be finally determined.

As described above, according to the pattern matching method (25) used in this embodiment, the position of a specific pattern in a target pattern can be detected at high speed.

The configuration shown in FIG. 13 shows an example for performing rough detection and fine detection. If a plurality of search range registers 93 are prepared, and the sampling interval and standard pattern are changed to the necessary values and sent to the timing signal generation circuit 12 and the standard pattern register 17 to specify the matching operation, a wide variety of patterns can be obtained. It can be used to detect objects.

These controls may be realized by a dedicated circuit, or may be realized by a program using a general-purpose program-embedded arithmetic processing device. According to the latter method, multiple standard patterns are provided as a countermeasure in case matching with each standard pattern is not successful, or matching is performed by checking the relative positional relationship of the matching result positions of multiple standard patterns. It is also easy to confirm that is correct.

In the above embodiments, the video signal is binarized and processed26), but the video signal may be converted into a multi-valued digital quantity of multiple bits or processed as an analog signal. . In that case, the portrait memory and matching calculation section may be replaced with those having the same functions as those of the above-described embodiment.

〔Effect of the invention〕

As explained above, according to the present invention, since fine detection is performed by narrowing down the search range after rough detection, the position of the target pattern is detected with the necessary accuracy using a simpler device than when only fine detection is performed from the beginning. can do. In particular, if the partial pattern extraction circuit and the extraction circuit for the extracted partial pattern and the standard pattern are switched between coarse detection and fine detection, the device configuration becomes simpler.

[Brief explanation of the drawing]

Fig. 1 is an explanatory diagram showing an example of a miscellaneous pattern, Fig. 2 is an explanatory diagram showing a method of changing the scanning axis, and Fig. 3 is an explanatory diagram showing a method of changing the sampling interval (27). is an explanatory diagram showing a standard pattern for fine detection, Fig. 5 is an explanatory diagram showing a fine detection method, Fig. 6 is an explanatory diagram showing detection of an uneven ridgeline, and Fig. 7 is a standard pattern for fine detection. FIG. 8 is a block diagram showing an example of the overall configuration of the apparatus according to the present invention, FIG. 9 is a block diagram of an example of the configuration of the image memory and local extraction section, and FIG. 10 is an example of the configuration of the matching circuit. 11 is a block diagram of an example of the configuration of the minimum value detection circuit. FIG. 12 is a block diagram of an example of the configuration of the XY coordinate and timing signal generation section.
FIG. 3 is a block diagram of a configuration example of the coordinate calculation section, and FIG. 14 is an explanatory diagram showing the order of rough detection and fine detection. DESCRIPTION OF SYMBOLS 1... Video, 2... Target, 3... "5"-shaped pattern, 11... Synchronization signal generation circuit, 12... Timing signal generation circuit, 13... Image input device, 14...
- Binarization circuit, 15... Video memory, 16... Two-dimensional local extraction section, 17... Standard pattern register, 1
8... Matching circuit, 19... Minimum detection circuit, 2
0...Register, 21...Calculation circuit, 22...Memory, 23...Operation control (28) (29) 81 Figure No. , 3 (B) (Z)
Fig. 84 Fig. 5 Fig. 10 Glass No. 8 Fig. Flute II Fig. ■ ■ Ko 13) Fig. 614 Continuation of Fig. 1 page 0 Inventor Rijun Hamada 292 Yoshida-cho, Totsuka-ku, Yokohama City, Hitachi, Ltd. Production Technology Laboratory @ Inventor: Isamu Yamazaki, 1450 Kamimizu Honmachi, Kodaira City, Musashi Factory, Hitachi, Ltd.

Claims (1)

[Claims] 1. A device for imaging a target pattern, and a first signal representing a pattern obtained by sampling the target pattern at a first sampling interval from a video signal obtained from the imaging device, and a first signal representing a pattern obtained by sampling the target pattern at a first sampling interval. means for generating a second signal representing a pattern sampled at a second sampling interval smaller than the first sampling interval; means for detecting a position of a first pattern; means for determining a second search area smaller than the first search area from the first pattern position; and means for determining a second search area in the second signal. The second part in the target pattern from the part belonging to the area
and means for detecting the position of the first pattern with higher precision than the position of the first pattern. 2. The first pattern position detecting means detects a pattern obtained by sampling the pattern of the first partial area at a predetermined position during the target pattern (1) at the first sampling interval. , a first means for storing as the first pattern, and a position of a partial image area having a pattern matching the first pattern from a portion of the first signal belonging to the first search area. 1. The pattern position detecting device according to item 1, comprising a second means for detecting the position of the first pattern. 3. The second means corresponds to a plurality of partial regions having the same size as the first partial region, and each pattern of the plurality of partial image regions located at different positions within the first search region. and the first pattern based on the first signal portion belonging to the first search area and the first pattern.
and a fourth means for detecting the position of the first pattern based on the detected degree of coincidence. 4. The third means includes a fifth means for sequentially cutting out patterns of partial image regions (2) of a first size located at mutually different positions in the first search area; 3. The pattern position detecting device according to claim 3, further comprising a sixth means for detecting the degree of coincidence based on the first pattern. 5. The second pattern position detecting means stores a pattern obtained by sampling a pattern of a second partial area at a predetermined position in the target pattern at the second sampling interval as the second pattern. 7th to do
means for detecting the position of a partial image area having a pattern matching the second pattern from a portion of the second signal belonging to the first search area as the position of the second pattern; 8. A pattern position detecting device according to the first term or the second term, which comprises the means described in item 8. 6. The eighth means corresponds to a plurality of partial regions having the same size as the second partial region, and the eighth means corresponds to the patterns of each of the plurality of partial regions located at different positions within the first search region. a ninth means (3) for detecting the degree of coincidence with the second pattern based on the first signal portion belonging to the first search area and the second pattern; and a tenth means for detecting the position of the second pattern based on the matching degree. 7. The first pressure means are located at different positions in the first search area. an eleventh means for sequentially cutting out patterns of a partial image area of a first size; and a first means for detecting the degree of coincidence based on the cut out patterns and the first pattern.
6. The pattern position detection device according to item 6, comprising the means of item 2. 8. The first standard pattern is a pattern that exists only once in the first search area, and a plurality of the second standard patterns exist in the first search area, but the second The pattern position detecting device according to any one of items 1 to 7, in which only one pattern exists in the search area. 9. The pattern position detection device according to any one of items 2 to 8, wherein the second partial area is a part of the first partial area. 10. A device for imaging the target pattern, and the imaging device (4
) A first signal representing a pattern obtained by sampling the target pattern at a first sampling interval, and a first signal representing a pattern obtained by sampling the target pattern at a second sampling interval smaller than the second sampling interval. means for switching and generating a second signal representing a turn; the first or second signal being switched and input;
means for sequentially cutting out partial pattern signals consisting of a predetermined number of picture elements; Second
The patterns of the partial areas of the first . The patterns sampled at the second sampling interval are
．． means for storing the first standard pattern as a second standard pattern; comparing means for switching and comparing the output of the cutting means and the contents of the first and second standard patterns when each second signal is input; Based on the output of the comparison means when inputting,
means for detecting the position of a partial image area having a pattern matching the first standard pattern (5); and determining a second search area smaller than the first search area based on the detected position. and a pattern matching the second standard pattern in the second search area based on the output of the comparison means when the second signal is input to the extraction means. A pattern position detection device comprising means for detecting the position of a partial image area. 11. Said 1st. 10. The pattern position detection device according to item 10, wherein the number of picture elements of the second standard pattern is both equal to the predetermined number.