JP2001147138A - Device and method for automatically reading indicator - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a device and a method for automatically reading an indicator so as to quickly read a pointed value of the indicator in various kind of measurement controlling equipment used in a plant and the like in the same reading way as an operator. SOLUTION: Previously, each coordinate value of a pointer visually determined to be on each scale by an operator is found as an index. In actual reading, a reading value of the pointer is decided on the basis of the coordinate value of the pointer at that time and the previously found index.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an automatic indicator reading device and a method for automatically reading an indicator value of an indicator in various measurement control equipment used in a plant or the like.

[0002]

2. Description of the Related Art In a plant or the like, reading the value of an indicator in various measurement and control equipments is performed automatically without an operator or the like from the viewpoints of labor saving, work efficiency and improvement of work environment. May need to be done at 8 and 9 are diagrams each showing an example of a general indicator. The indicator shown in FIG. 8 is of a type in which a pointer 6 moves up and down on a scale plate 8 provided with a scale 7 based on measured values and the like. The indicator shown in FIG. 9 is integrated with a recorder, and a pen tip 10 that moves based on the measured values and the like records the measured values and the like on a recording paper 9 as a locus 11 and the pen tip The pointer 6 is a type in which the pointer 6 moves right and left together with 10 to indicate a value on the scale plate 8. Therefore, it may be called a recorder with an indicator (indicator).

As a device for automatically reading the indicated value of the indicator, there is a device as shown in FIG. FIG. 10 is a configuration diagram showing an example of a conventional indicator automatic reading device. As shown in the figure, a conventional apparatus includes a camera 1 installed at a fixed position for photographing an indicator, an image input apparatus 2 for inputting an image photographed by the camera 1 as a digital image to an image processing apparatus 3, and an image processing apparatus. Guideline 6
The image processing apparatus 3 obtains a reading value of the image data, and the result output apparatus 4 outputs the obtained reading value.

FIGS. 11 and 12 show an example of a processing flow in the image processing apparatus 3 of the conventional apparatus. First, FIG. 1 assuming that the indicator shown in FIG. 8 is read.
1 will be described. First, an image captured by the camera 1 is input to the image processing device 3 via the image input device 2 (step S01 in FIG. 11). The scale 7 near the pointer 6 is extracted from the input image, and its vertical (vertical) coordinate value is calculated (step S in FIG. 11).
02). Similarly, the coordinate value of the pointer 6 in the vertical direction is calculated (step S03 in FIG. 11).

Next, the obtained coordinate value of the pointer 6 and the pointer 6
From the coordinate values of the scale 7 before and after (located immediately above and below)
Calculate the reading of the pointer 6 (step S0 in FIG. 11).
4). The calculation is performed by linear approximation from those coordinate values and the value of the scale 7. Subsequently, a visual correction process is performed on the obtained reading value (step S0 in FIG. 11).
5). The visual correction is a process for correcting a shift (error) due to the fact that the pointer 6 cannot be always viewed from a direction perpendicular to the scale plate 8 because the camera 1 is installed at a fixed position.

FIG. 13 is a diagram for explaining the situation. When a person such as an operator reads the indicator, the pointer 6 is usually viewed from a direction perpendicular to the scale plate 8, so that a substantially correct reading can be obtained. However, as shown in the figure, since the position of the camera 1 is fixed, there is no problem if the pointer 6 is located at the position A in the figure, but if the pointer 6 is located at a position such as B, the correct reading is performed. Error against the value (
X). Therefore, in order to obtain a value equivalent to a case where a person reads, a correction process for that is necessary. Such visual correction is performed by a complicated calculation process using parameter values such as camera position, camera distortion, and focal length.

Finally, the corrected reading value of the pointer 6 is output to the result output device 4 as a processing result of the image processing device 3 (step S06 in FIG. 11). On the other hand, the flow shown in FIG. 12 shows a processing flow when the recorder with the indicator (indicator) shown in FIG. 9 is read by the conventional device.
In particular, the case where the locus 11 of the pen tip 10 on the recording paper 9 is read is shown. The basic processing is the same as that described above with reference to FIG. 11, except that the pointer 6 and the scale plate 8 are replaced with the pen tip 10 and the recording paper 9. Conventionally, automatic reading has been performed by the indicator automatic reading device as described above.

[0008]

However, in the conventional device, accurate camera parameter values (camera position, camera distortion, focal length, etc.) are required to perform the visual correction processing, and the measurement requires a great deal of time. The cost is high, and the calculation of the correction processing is complicated. When the pointer 6 is on the scale 7 and a person reads it, the reading is immediately changed to the scale 7.
However, in the conventional apparatus, such a way of reading is not realized, and the calculation processing is performed in the same manner as when the pointer 6 is located at another position. Therefore, especially when the line width of the scale 7 is wide, it is considered that the read value often differs from that when human reads.

Accordingly, an object of the present invention is to provide an indicator capable of rapidly reading an indicator value of an indicator in various measurement and control equipment used in a plant or the like in a manner similar to the case where an operator or the like reads. An automatic reading device and method are provided.

[0010]

In order to achieve the above-mentioned object, one aspect of the present invention is to provide a method in which each coordinate value of a pointer when it is determined in advance by a human eye that the pointer is on each scale. Is determined as an index, and at the time of actual reading, the reading value of the pointer is determined based on the coordinate value of the pointer at that time and the previously determined index. Therefore, according to the present invention, it is possible to quickly perform automatic reading similar to the case of reading by an operator or the like.

In order to achieve the above object, another aspect of the present invention is a camera for taking an image of an indicator indicating an indicated value by a position of a pointer moving on a graduated scale plate, In the indicator automatic reading device having an image processing device that determines the reading value of the hands based on the position coordinates of the hands obtained by performing image processing on the captured image,
The image processing apparatus, in advance, for each of the scales, the position coordinates of the hands obtained when the hands are placed at a position where a person determines that the hands are on the scales are stored as an index, The reading value of the pointer at the time of automatic reading is determined based on the position coordinates of the pointer at the time of automatic reading and the index.

Further, in the above-mentioned invention, it is preferable that the determination of the reading value of the hands at the time of the automatic reading be performed by determining the position coordinates of the hands at the time of the automatic reading and the position coordinates above and below the position coordinates. The calculation is performed by interpolation calculation from the values of the two indexes and the values of the two scales corresponding to the two indexes.

[0013] In the above invention, another aspect is as follows.
The index stored for each of the scales has the position coordinates of the two hands obtained when the hand is placed at a position where a person determines that the hands are at both ends of the width of the line representing the scale. When the value of the position coordinates of the hands at the time of the automatic reading is located between the two position coordinates of the index, the reading value of the hands at the time of the automatic reading is changed to the scale corresponding to the index. It is characterized by the value of

Further, in the above invention, another aspect is as follows.
The indicator is an indicator of the recorder that indicates an indication value by a pointer linked with a pen of the recorder.

[0015] In order to achieve the above object, still another aspect of the present invention is to perform image processing on an image of an indicator indicating an indicated value by a position of a pointer moving on a graduated scale plate. In an automatic reading method of an indicator that determines a reading value of the pointer based on the position coordinates of the pointer obtained by the image processing, a position where a person determines that the pointer is present on each scale is prepared in advance. The reading value of the hands at the time of automatic reading is determined based on the position coordinates of each hand obtained when the hands are placed on the hand and the position coordinates of the hands at the time of automatic reading.

Further objects and features of the present invention will become apparent from the embodiments of the present invention described below.

[0017]

Embodiments of the present invention will be described below with reference to the drawings. However, such embodiments do not limit the technical scope of the present invention.
In the drawings, the same or similar components are denoted by the same reference numerals or reference symbols.

FIG. 1 is a block diagram showing a first embodiment of an automatic indicator reading apparatus to which the present invention is applied. The configuration of the apparatus according to the first embodiment is substantially the same as the configuration of the conventional apparatus shown in FIG. 10, except that the image processing apparatus 3 has an index table 5 described later. The apparatus according to the first embodiment prepares coordinate values of the hands 6 when the hands 6 are on the scales 7 as indexes for each scale 7 and reads the hands 6 using the values. This is an apparatus for automatically reading an indicator of the type shown in FIG.

Hereinafter, the specific contents of the apparatus according to the first embodiment will be described. First, before the actual automatic reading is performed, the index table 5 is created. FIG.
FIG. 6 is a diagram illustrating an example of an index table 5; As shown in the figure, the index table 5 has a scale (value).
And an index (coordinate value) corresponding thereto, and the index is obtained by the following procedure. One scale 7 is selected (for example, scale N in the figure), and when an operator or the like reads the indicator, the pointer is set at a position where it is determined that the pointer 6 is on the scale. In this state, the indicator automatic reading device of this embodiment executes a reading process, and calculates the coordinate values of the hands 6 (step S2 in FIG. 3 described later) by the coordinate values of the hands 6 (Yn in the figure). ) Is calculated. The calculated coordinate value is used as an index of the scale 7. The above processes are executed for all necessary scales 7. The index table 5 created by the above procedure is stored in the image processing device 3.

Next, an actual automatic reading process is performed. FIG.
FIG. 4 is a diagram showing a processing flow in the image processing device 3 of the automatic indicator reading device according to the present embodiment. The photographing of the indicator by the camera 1 and the input of the image photographed by the image input device 2 to the image processing device 3 (Step S1 in FIG. 3)
Is performed in the same manner as in the conventional apparatus.

Next, the coordinate value y of the pointer 6 in the vertical direction (the direction in which the value of the scale changes) is obtained from the input image (step S2 in FIG. 3). FIG. 4 is a diagram showing an example of a process in the step of calculating the pointer coordinates. First, guideline 6
Is binarized (step S21 in FIG. 4). next,
The binarized result is projected in the horizontal direction (step S22 in FIG. 4). And the vertical direction (vertical direction) of the projection
The maximum value of the coordinates is searched, and the value is set as the coordinate value y of the pointer 6 (step S23 in FIG. 4). Other methods may be used for this coordinate calculation process.

Next, returning to FIG. 3, the obtained coordinate value y of the pointer 6 and the previously prepared index table 5 will be described.
, The reading of the pointer 6 is calculated (step S in FIG. 3).
3). FIG. 5 is a diagram for explaining the calculation of the pointer reading value. The reading value of the pointer 6 is linearly approximated from the two indexes Ym and Yn in the index table 5 whose values are above and below the coordinate value y of the pointer 6 and the corresponding values M and N of the scale 7. We ask by doing. That is, the following (1)
When the relationship of the formulas is established, it is obtained by the following formula (2). Ym <y <Yn (1) Reading value of pointer 6 = ((y−Ym) / (Yn−Ym)) × (N−M) + M (2) Here, a linear interpolation formula was used. , Other interpolation formulas may be used. Finally, the calculated reading value of the pointer 6 is output from the result output device 4 (step S4 in FIG. 3), and the processing of the indicator automatic reading device ends.

When the width of the scale 7 is wide, the index of each scale 7 is provided with a range, and when the coordinate value y of the pointer 6 falls within the range, the reading of the pointer 6 is read. The value of the scale 7 may be used. In this case, when the index table 5 is generated, the coordinate values when the hands 6 are set at the upper end and the lower end of each scale 7 are obtained, and the two coordinate values are used as the index of the scale 7. it can.

Next, a second embodiment to which the present invention is applied will be described. In the second embodiment, the present invention is applied to a recorder with an indicator (indicator) illustrated in FIG. The device according to the present embodiment is substantially the same as the automatic indicator reading device according to the first embodiment described above, and the following description will focus on the differences. The configuration of the apparatus is the same as that of the apparatus according to the first embodiment shown in FIG.

In the apparatus according to the second embodiment, first, the index table 5 is created in advance. The difference from the first embodiment is that before the preparation, the both ends of the scale 7 of the scale plate 8 and the both ends of the scale of the recording paper 9 are confirmed to coincide with each other. This is a position where it is determined that the locus 11 exists on the scale. Hereinafter, the index table 5 is created and stored in the same manner as the contents described in the first embodiment. Note that, in the second embodiment, since the recorder shown in FIG. 9 is targeted, the coordinate value serving as an index is a value in the horizontal direction unlike the case of the first embodiment.

Next, the created index table 5
The actual automatic reading is performed on the basis of the flowchart shown in FIG. 3, and the processing flow is the same as that shown in FIG. 3 described in the first embodiment. When an image captured by the camera 1 is input to the image processing device 3 via the image input device 2, first, calculation of pointer coordinates (step S2 in FIG. 3) is performed. FIG. 6 is a diagram showing an example of the processing procedure. Basically, FIG.
However, since the direction of the scale 7 is different as described above, the processing of the projection after binarization is performed in the vertical direction (step S2 in FIG. 6).
2 '). Otherwise, the same process is performed to obtain the horizontal coordinate value x of the pointer 6.

Next, the reading value of the pointer 6 is the coordinate value x of the pointer 6.
Is calculated from the index table 5 created in advance (step S3 in FIG. 3). The concept of this calculation method is the same as that of the first embodiment, but the direction of the coordinate value is different. FIG. 7 is a diagram for explaining calculation of a pointer reading value in the case of the second embodiment. The reading value of the pointer 6 is calculated by using two indexes in the index table 5 whose values are located above and below the coordinate value x of the pointer 6.
It is determined by linear approximation from Xm and Xn and the corresponding values M and N of the scale 7. That is, when the relationship of the following equation (3) is established, the value is obtained by the following equation (4). Xm <x <Xn (3) Reading value of pointer 6 = ((x−Xm) / (Xn−Xm)) × (N−M) + M (4) Here, a linear interpolation formula is used. , Other interpolation formulas may be used.

Finally, the calculated reading value of the pointer 6 is output from the result output device 4 (step S4 in FIG. 3).
The processing is also completed in the device according to the second embodiment. In the device according to the second embodiment, similarly to the first embodiment, when the width of the scale is wide, the index of each scale has a range, and the coordinate value x of the pointer 6 is changed. When the value falls within the range, the reading value of the pointer 6 may be used as the value of the scale.

As described above with reference to the first and second embodiments, by using the indicator automatic reading apparatus to which the present invention is applied, it is possible to obtain a reading close to the case where an operator or the like reads at the time of automatic reading. A value can be obtained, and complicated calculation processing for visual correction, which is required in the conventional device, is not required, and rapid processing can be performed. In addition, as in the second embodiment, when reading a recorder with an indicator, the value of the pointer is read. There is no need to wait until it is, and the process is quick.

The scope of protection of the present invention is not limited to the above embodiments, but extends to the inventions described in the claims and their equivalents.

[0031]

As described above with reference to the accompanying drawings, the present invention has the following effects.

First, each coordinate value of the pointer when the pointer is judged to be on each scale by a human eye is obtained as an index in advance, and based on the index at the time of actual reading. Is determined, the same result as in the case where an operator or the like reads the data can be obtained quickly.

Second, the reading value of the hands is calculated from the position coordinates of the hands, the values of the two indexes located above and below the position coordinates, and the values of the two scales corresponding to the two indexes. , By the interpolation calculation, it is possible to quickly obtain a reading value similar to a case where the reading is performed by an operator or the like.

Third, the index is provided with a range in consideration of the scale width, and when the coordinate value of the pointer falls within the range, the reading of the pointer is used as the value of the scale of the index. In the case where there is a pointer on the scale, how to read by the reader as the value of the scale can be realized in the automatic reading.

Fourth, when reading the recorder, it is necessary to wait until the trajectory has a readable length, as in the conventional device for reading the trajectory of the pen tip, by reading the value of the pointer of the pointing unit. Therefore, the automatic reading process can be performed quickly.

[Brief description of the drawings]

FIG. 1 is a configuration diagram according to a first embodiment of an automatic indicator reading apparatus to which the present invention is applied.

FIG. 2 is a diagram showing an example of an index table 5;

FIG. 3 is a diagram showing a processing flow in the image processing apparatus 3 of the automatic indicator reading apparatus according to the first embodiment.

FIG. 4 is a diagram showing an example of a pointer coordinate calculation process in the first embodiment.

FIG. 5 is a diagram for explaining calculation of a pointer reading value in the first embodiment.

FIG. 6 is a diagram illustrating an example of a process of calculating a pointer coordinate according to the second embodiment.

FIG. 7 is a diagram for explaining calculation of a pointer reading value in the second embodiment.

FIG. 8 is a diagram showing an example of a general indicator.

FIG. 9 is a diagram illustrating an example of a recorder with an indicator.

FIG. 10 is a configuration diagram showing one example of a conventional indicator automatic reading device.

FIG. 11 is a diagram showing an example of a processing flow in an image processing device 3 of a conventional device.

FIG. 12 is a diagram showing an example of a processing flow in an image processing device 3 of a conventional device.

FIG. 13 is a diagram for explaining visual correction.

[Explanation of symbols]

 Reference Signs List 1 Camera 2 Image input device 3 Image processing device 4 Result output device 5 Index table 6 Pointer 7 Scale 8 Scale plate 9 Recording paper 10 Pen tip 11 Trace

Claims (5)

[Claims] 1. A camera for photographing an image of an indicator representing an indicated value by a position of a pointer moving on a graduated scale plate, and an image obtained by performing image processing on the photographed image. An indicator automatic reading device having an image processing device that determines a reading value of the hands based on the position coordinates of the hands, wherein the image processing device is provided for each of the scales in advance, when the hands are on the scales. The position coordinates of the pointer obtained when the pointer is placed at the position determined by are stored as an index, and the reading value of the pointer at the time of automatic reading is read as the position coordinates of the pointer at the time of the automatic reading. An automatic indicator reading device characterized in that it is determined based on an index. 2. The method according to claim 1, wherein the determination of the reading value of the pointer at the time of the automatic reading includes: a position coordinate of the pointer at the time of the automatic reading; and two values of the index positioned above and below the value of the position coordinate. When,
An automatic indicator reading device, wherein interpolation is performed from two scale values corresponding to the two indexes. 3. The index according to claim 1, wherein the index stored for each scale is obtained when the pointer is placed at a position where a person determines that the pointer is at each of both ends of the width of the line representing the scale. The position coordinates of the hands at the time of the automatic reading is located between the two position coordinates of the index, the position of the hands at the time of the automatic reading An automatic indicator reading device, wherein a reading value is a value of the scale corresponding to the index. 4. An instruction according to claim 1, wherein the indicator is an indicator of the recorder which indicates an indication value by a pointer linked with a pen of the recorder. Automatic reading device. 5. An image processing device performs an image processing on an image of the indicator representing an indicated value by a position of a pointer moving on a scale plate provided with a scale, and performs the image processing based on the position coordinates of the pointer obtained by the image processing. In an automatic reading method of an indicator for determining a reading value of a pointer, a position coordinate of each pointer obtained when the pointer is placed at a position prepared by a person at a position where a person determines that the pointer is present on each scale. And determining a reading value of the pointer at the time of automatic reading based on the position coordinates of the pointer at the time of automatic reading.