JP2002010997A - Photographing device, image processor, image processing system, operation control method and storage medium - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a photographing device capable of acquiring stable excellent images at all times by objectively reporting a state at the time of image acquisition to a user. SOLUTION: An extraction means 113a extracts a prescribed value (feature amount) from photographed images (X-ray images). Alarming means 111 and 112 perform alarming by screen display and voice output based on the result of verifying whether or not the prescribed value obtained in the extraction means 113a is within a prescribed range. Thus, the user easily and accurately recognizes whether or not a present photographing state (X-ray amount or the like) is an optimum state or the like.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to, for example, extracting a characteristic amount from a photographed image obtained by radiography (such as X-ray), and performing image processing such as gradation conversion processing on the photographed image based on the characteristic amount. Used in devices and systems that perform
The present invention relates to a photographing device, an image processing device, an image processing system, an operation control method, and a storage medium in which a computer stores processing steps for implementing the method.

[0002]

2. Description of the Related Art In recent years, with the advance of digital technology, for example, a captured image obtained by X-ray photography is digitized, and the digital image is subjected to image processing and displayed on a monitor device, or used for X-ray diagnosis. The output on the film has been done.

As the image processing described above, there is a gradation conversion process for converting a density value of a captured image into a density value which can be easily observed on a monitor screen, a film, or the like which is an output destination of the captured image. In this gradation conversion process, for example, when a captured image obtained by X-ray imaging of a lung region is output to a film for X-ray diagnosis, first, histograms of all pixels constituting the captured image are created, Analyze the histogram. Then, as a feature amount of the captured image, a pixel value of a certain partial point (upper 5% point or the like) of the histogram is extracted. Density value conversion (gradation conversion) is performed so that the extracted pixel value (feature amount) has a constant density value (eg, a density of about 1.9) on the film.

[0004]

However, in the conventional X-ray imaging apparatus having the above-described image processing function, the subsequent processing is executed unconditionally regardless of the state of the feature used in the image processing. It had been. That is, even when the feature amount extracted from the captured image is not in an appropriate state due to an excess or deficiency of the X-ray dose in the X-ray imaging, the subsequent process is executed unconditionally regardless of the user's intention. It had been. For this reason, the user cannot grasp that the photographing has failed only after the captured image is output on the monitor device or the film.

[0005] In addition, since the user could not know whether the X-ray dose during X-ray imaging was appropriate or not, an excessively large X-ray dose was required to obtain an optimal captured image. May have been emitted. This is particularly a problem in the case of X-ray photography for diagnosis or the like, for reasons of protecting the human body.

Accordingly, the present invention has been made to eliminate the above-mentioned drawbacks, and aims to always obtain a stable and good image by objectively informing the user of the state at the time of image acquisition. It is an object of the present invention to provide a photographing apparatus, an image processing apparatus, an image processing system, an operation control method, and a storage medium in which a computer stores the processing steps for implementing the method.

[0007]

For such a purpose,
A first invention is characterized by comprising extraction means for extracting a predetermined value from a photographed image, and warning means for giving a warning based on the predetermined value obtained by the extraction means.

[0008] In a second aspect based on the first aspect,
A display unit for displaying a predetermined value obtained by the extraction unit on a screen is provided.

[0009] In a third aspect based on the first aspect,
The warning means notifies the verification result by at least one of a screen display and a sound output based on a verification result of whether the predetermined value is within a predetermined range.

In a fourth aspect based on the first aspect,
The extraction means extracts the predetermined value from a predetermined area of the photographed image.

According to a fifth aspect of the present invention, in the fourth aspect,
The predetermined region includes a subject region to be photographed.

According to a sixth aspect of the present invention, in the fourth aspect,
The extraction means extracts a maximum pixel value in the predetermined area as the predetermined value.

[0013] In a seventh aspect based on the first aspect,
The extraction means extracts the predetermined value based on a histogram analysis result of a pixel value of the captured image.

According to an eighth aspect based on the first aspect,
The captured image includes an image obtained by radiography,
The extraction unit includes a pass-through region from the photographed image and a pass-through deletion unit that deletes a region in contact with the pass-through region at a constant interval, and extracts the predetermined value from the image after the pass-through deletion by the unit. It is characterized by.

According to a ninth aspect, in the first aspect,
The photographed image includes an image obtained by radiographing a lung as a subject.

A tenth invention is an image processing apparatus for extracting a predetermined amount from a photographed image and performing image processing on the photographed image using the predetermined amount. It has a function of a photographing device.

An eleventh invention is an image processing system in which a plurality of devices are communicably connected to each other, wherein at least one of the plurality of devices is one of the first to ninth embodiments. It has a function of a photographing device or a function of the image processing device according to claim 10.

A twelfth invention is an operation control method for photographing an arbitrary subject, wherein a warning is issued based on a verification result as to whether or not a predetermined value extracted from the photographed image is within a predetermined range. Is performed.

According to a thirteenth aspect, in the twelfth aspect, a display step of displaying the predetermined value on a screen is provided.

In a fourteenth aspect based on the twelfth aspect, the warning step includes at least one of a step of displaying the verification result on a screen and a step of outputting a sound based on the verification result. It is characterized by the following.

A fifteenth invention is characterized in that, in the twelfth invention, an extraction step of extracting the predetermined value from a predetermined area of the photographed image is provided.

In a sixteenth aspect based on the fifteenth aspect, the predetermined area includes a subject area to be photographed.

In a seventeenth aspect based on the fifteenth aspect, the extracting step includes a step of extracting a maximum pixel value in the predetermined area as the predetermined value.

In an eighteenth aspect based on the fifteenth aspect, the extraction step includes a step of extracting the predetermined value based on a histogram analysis result of pixel values of the photographed image.

In a nineteenth aspect based on the fifteenth aspect, the photographed image includes an image obtained by radiography, and the extracting step includes the step of determining a pass-through area and a pass-through area from the photographed image. It is characterized by including a pass-through deletion step of deleting an area that is in contact at a fixed interval, and a step of extracting the predetermined value from the image after the pass-through deletion in this step.

According to a twentieth aspect, in the twelfth aspect, the photographed image includes an image obtained by radiographing a lung as a subject.

According to a twenty-first aspect, a computer-readable storage medium stores the processing steps of the operation control method according to any one of claims 12 to 20.

[0028]

Embodiments of the present invention will be described below with reference to the drawings.

The present invention is applied to, for example, an X-ray imaging apparatus 100 as shown in FIG. This X-ray imaging apparatus 100
Has an alarm function for objectively informing the success or failure of imaging. As shown in FIG. 1, the X-ray generation circuit 101 for generating X-rays and the X-ray light transmitted through the subject 103 are imaged. Two-dimensional X-ray sensor 104, a data collection circuit 105 for collecting captured images output from the two-dimensional X-ray sensor 104, and a pre-processing circuit 106 for performing pre-processing on the captured images collected by the data collection circuit 105 And the preprocessing circuit 1
The main memory 109 stores various information such as a captured image (original image) pre-processed in step 06 and a processing program for executing various processes, and instructs the apparatus to execute X-ray imaging and other instructions and various settings. Operation panel 110 for performing the above operation, and a feature extraction circuit 11 for extracting a predetermined value (feature amount) from a captured image (original image) preprocessed by the preprocessing circuit 106
3 and an image processing circuit 1 that performs image processing such as gradation conversion processing on a captured image (original image) that has been preprocessed by the preprocessing circuit 106 using the feature amount obtained by the feature extraction circuit 113.
14, an image display 111 for displaying a captured image or the like after processing by the image processing circuit 114, a sound generator 112 for issuing an alarm, and a CPU 1 for controlling the operation of the entire apparatus.
08, a data collection circuit 105, a preprocessing circuit 106, a feature extraction circuit 113, an image processing circuit 114,
CPU 108, main memory 109, operation panel 11
0, the image display 111, and the sound generator 112 are connected to the CPU bus 107, respectively, so that data can be exchanged with each other.

Here, the feature extraction circuit 113 verifies the feature amount extracted from the subject area of the original image, displays the image on the image display 111 based on the verification result,
A warning is issued by the sound generator 112,
The configuration is the most characteristic in the present embodiment. For this reason, the feature extraction circuit 113 extracts a feature amount from the subject region of the original image, and verifies whether the feature amount obtained by the feature amount extraction circuit 113a is within a predetermined range. Verification circuit 113b. Therefore, the image display 111 and the sound generator 112
The operation is performed based on the verification result of the verification circuit 113b.

Therefore, the X-ray imaging apparatus 100 as described above
First, in the main memory 109, the CPU 10
The data and processing programs required for executing various processes in step 8 are stored in advance, and include a work memory for the CPU 108 to work with. Main memory 109
Here, as a processing program for verifying a feature amount, and for displaying a screen or outputting an alarm based on the verification result, for example, the processing program stored in FIG.
A processing program according to the flowchart of FIG. Therefore, the CPU 108 reads out the above-described processing program from the main memory 109 and executes the processing program to control the operation of the entire apparatus as described below in accordance with the operation from the operation panel 110.

1. Main processing (see Fig. 2)

Step S200: First, the X-ray generation circuit 1
Numeral 01 radiates the X-ray beam 102 to the inspection object 103. The X-ray beam 102 emitted from the X-ray generation circuit 101 passes through the subject 103 while attenuating, reaches the two-dimensional X-ray sensor 104, and is output as an X-ray image by the two-dimensional X-ray sensor 104. Is done. here,
An X-ray image output from the two-dimensional X-ray sensor 104 is, for example, a lung front image or a limb image. Next, the data collection circuit 105 converts the X-ray image output from the two-dimensional X-ray sensor 104 into an electric signal, and converts the X-ray image into an electric signal.
6 The preprocessing circuit 106 includes the data collection circuit 1
Pre-processing such as offset correction processing and gain correction processing is performed on the signal (X-ray image signal) from step 05. The X-ray image signal preprocessed by the preprocessing circuit 106 is input to the main memory 109, the feature extraction circuit 113, and the image processing circuit 114 via the CPU bus 115 under the control of the CPU 108 as input image information. Each is transferred.

Step S201: In the feature extracting circuit 113, first, the feature amount extracting circuit 113a converts a feature amount from an input image (hereinafter, also referred to as a "target image") transferred under the control of the CPU 108, which will be described in detail later. Is extracted. Then, the feature quantity extraction circuit 113a supplies the extracted feature quantity to the verification circuit 113b and the image display 111, respectively.

Step S202: The image display device 111
The feature amount from the feature amount extraction circuit 113a is displayed on a screen.

Step S203: On the other hand, verification circuit 113
b verifies whether the characteristic amount from the characteristic amount extraction circuit 113a is within a predetermined range, and supplies the verification result to the image display 111 and the sound generator 112, respectively.

Step S204: The image display 111
If the verification result from the verification circuit 113b indicates that the feature amount is not within the predetermined range, a screen display for notifying (warning) of the fact is performed. The sound generator 112 is connected to the verification circuit 1
As a result of the verification from 13b, if the feature amount is not within the predetermined range, an audio output for notifying (warning) to that effect is performed. With this, the user is notified when an alarm is issued.
An operation or the like for taking a picture again is performed.

Step S205: As described above, X
When a line image is captured and an appropriate feature amount is obtained from the captured image, the feature amount is supplied to the image processing circuit 114. The image processing circuit 114 performs image processing such as a gradation conversion process using the above-mentioned feature amount on the input image transferred under the control of the CPU 108. This image processing circuit 1
The image after the image processing in 14 is displayed on the image display 111 or output on a film.

2. Feature amount extraction processing (step S201:
The feature extraction circuit 113a of the feature extraction circuit 113 executes the following processes of steps S301 to S303.
Here, a case will be described in which the input image (target image) is a lung front image and the maximum value of the pixel values in the lung region is extracted as a feature value.

Step S301: First, an X-ray irradiation area is extracted from an input image by using an arbitrary method (for example, the method described in Japanese Patent Application No. 10-243020).

Step S302: Next, in the target image, the outside of the irradiation region, the through region and the body region that is in contact with the through region within a predetermined interval are replaced with, for example, pixel value = "0". Specifically, input image data f (x, y)
As

[0042]

(Equation 1)

The image is converted by the following equation (1).
The image data f1 (x, x) in which the outside of the irradiation region, the through region and the body region in contact with the through region within a certain interval are deleted.
y) is obtained. “Sng (x, y)” in equation (1)
Is

[0044]

(Equation 2)

It is expressed by the following equation (2). This equation (2)
In the equation, “Th1” is a constant determined in advance by experiments or the like, and is, for example, 5% of the maximum pixel value of the input image (original image). "D1" and "d2"
Is a constant that determines the constant interval (width) when deleting a body region that is in contact with the through region within a certain interval.

Step S303: and step S3
02, the maximum value of the pixels of the image f1 (x, y) obtained (the highest value of the image density value) is extracted as a feature amount.

Therefore, the feature quantity obtained in step S303, that is, the maximum density value extracted from a predetermined area (an area that has not been through-deleted) of the subject area of the input image is supplied to the verification circuit 113b. It will be supplied to the image display 111. Accordingly, as described above, the verification circuit 113 verifies whether the maximum density value is within a predetermined range, and the image display 111 displays the maximum density value on a screen. Further, the image display 111 and the sound generator display an alarm or generate an alarm based on the verification result of the verification circuit 113. Based on this, the user performs shooting again and the like. The optimum maximum density value obtained as a result is supplied to the image processing circuit 114, and the image processing circuit 114 performs gradation conversion of the image such that the maximum density value becomes, for example, 1.8 density.

As described above, in the present embodiment, the feature amount extracted from the captured image is displayed on the screen, and whether or not the feature amount is within a predetermined range is verified, and based on the verification result, , Alarm display and alarm generation. Accordingly, the user can easily and accurately grasp the current degree of the X-ray dose, so that it is possible to prevent an excessive amount of the X-ray from being emitted and prevent the X-ray dose from being excessive or insufficient. This is particularly effective for protecting the human body. In addition, since it is possible to easily and accurately grasp that the X-ray dose is not appropriate at that time, it is possible to immediately grasp that the radiographing has failed, and to perform re-imaging immediately. As a result, very efficient imaging can be performed. Furthermore, when the target image is a lung front image, the maximum value of the pixel in the lung region can be stably extracted, and the appropriate range of the maximum value is determined regardless of the subject in the image processing. In X-ray imaging of the lung part, more stable verification of the feature amount can be performed by using the maximum value of the pixels in the lung region as the feature amount.

In the above-described embodiment, the feature value extraction processing shown in FIG. 3 may be, for example, processing according to the flowchart of FIG. 4 (feature value extraction processing by histogram analysis). Specifically, for example, when the target image is a limb image or the like, first, an irradiation field region is extracted from the target image as described above (step S301),
The pass-through area is deleted (step S302). As a result, the image data f1 (x, y) is obtained (see the above equation (1)). Therefore, this image data f1
A histogram of (x, y) as shown in FIG. 5 is created (step S303). In FIG. 5, the horizontal axis indicates the pixel value, and the horizontal axis indicates the frequency. Then, in the histogram of FIG. 5, pixel values X1 and X2 corresponding to the peak value of the convex portion are extracted, and are used as feature amounts. In the case of such a configuration, in a limb image or the like, since the appropriate range of the feature amount extracted by the histogram analysis is determined regardless of the subject, more stable feature amount verification can be performed.

Further, in the above-described embodiment, when the feature amount is not within the predetermined range, both the screen display and the sound output for notifying the feature amount are performed. However, the present invention is not limited to this. The notification may be made by any one of the above means.

Another object of the present invention is to supply a storage medium storing program codes of software for realizing the functions of the host and the terminal of the above-described embodiment to a system or an apparatus, and to provide a computer (a computer) of the system or the apparatus. It is needless to say that the present invention can also be achieved by a CPU or an MPU) reading and executing a program code stored in a storage medium. In this case, the program code itself read from the storage medium implements the functions of the present embodiment, and the storage medium storing the program code constitutes the present invention. ROM, as a storage medium for supplying the program code,
Floppy (registered trademark) disk, hard disk, optical disk, magneto-optical disk, CD-ROM, CD-R,
A magnetic tape, a nonvolatile memory card, or the like can be used. By executing the program code read out by the computer, not only the functions of the present embodiment are realized, but also the OS and the like running on the computer perform actual processing based on the instructions of the program code. It goes without saying that a part or all of the above is performed, and the processing realizes the function of the present embodiment. Further, after the program code read from the storage medium is written to a memory provided in an extension function board inserted into the computer or a function extension unit connected to the computer, the function extension is performed based on the instruction of the program code. C provided on board and function expansion unit
It goes without saying that a PU or the like performs part or all of the actual processing, and the processing realizes the functions of the present embodiment.

[0052]

As described above, according to the present invention, a warning is issued based on a predetermined value extracted from a photographed image, so that the photographing state at that time can be easily and accurately grasped. . Thereby, stable shooting can be performed. Therefore, according to the present invention, the state at the time of image acquisition can be objectively notified to the user,
A stable and good image can always be obtained.

[Brief description of the drawings]

FIG. 1 is a block diagram illustrating a configuration of an X-ray imaging apparatus to which the present invention has been applied.

FIG. 2 is a flowchart illustrating a main process of the X-ray imaging apparatus.

FIG. 3 is a flowchart illustrating an example of a feature amount extraction process of the main process.

FIG. 4 is a flowchart for explaining another example of the feature amount extraction processing (processing by histogram analysis).

FIG. 5 is a diagram for explaining an example of the histogram.

[Explanation of symbols]

 REFERENCE SIGNS LIST 100 X-ray imaging apparatus 101 X-ray generation circuit 102 X-ray beam 103 subject 104 two-dimensional X-ray sensor 105 data collection circuit 106 preprocessing circuit 107 CPU bus 108 CPU 109 main memory 110 operation panel 111 image display 112 sound generator 113 Feature extraction circuit 113a Feature amount extraction circuit 113b Verification circuit

Claims (21)

[Claims] 1. An image capturing apparatus comprising: an extracting unit that extracts a predetermined value from a captured image; and a warning unit that issues a warning based on the predetermined value obtained by the extracting unit. 2. The apparatus according to claim 1, further comprising display means for displaying a predetermined value obtained by said extracting means on a screen.
The imaging device according to the above. 3. The method according to claim 2, wherein the warning unit notifies the verification result by at least one of a screen display and a sound output based on a verification result of whether the predetermined value is within a predetermined range. The photographing device according to claim 1. 4. The apparatus according to claim 1, wherein the extracting means extracts the predetermined value from a predetermined area of the photographed image.
The imaging device according to the above. 5. The photographing apparatus according to claim 4, wherein the predetermined area includes a subject area to be photographed. 6. The photographing apparatus according to claim 4, wherein said extracting means extracts a maximum pixel value in said predetermined area as said predetermined value. 7. The photographing apparatus according to claim 1, wherein the extracting means extracts the predetermined value based on a histogram analysis result of a pixel value of the photographed image. 8. The photographed image includes an image obtained by radiographic imaging, and the extracting means removes a through region from the photographed image and a region in contact with the through region at a constant interval. 2. The photographing apparatus according to claim 1, further comprising: means for extracting the predetermined value from the image after the deletion by the means. 9. The photographing apparatus according to claim 1, wherein the photographed image includes an image obtained by radiographing a lung as a subject. 10. An image processing apparatus for extracting a predetermined amount from a photographed image and performing image processing on the photographed image using the predetermined amount, wherein the function of the photographing apparatus according to any one of claims 1 to 9 is provided. An image processing apparatus comprising: 11. An image processing system in which a plurality of devices are communicably connected to each other, wherein at least one of the plurality of devices is one of a plurality of devices.
An image processing system having the function of the photographing device according to claim 9 or the function of the image processing device according to claim 10. 12. An operation control method for photographing an arbitrary subject, comprising: a warning step for issuing a warning based on a result of verifying whether a predetermined value extracted from the photographed image is within a predetermined range. An operation control method comprising: 13. The operation control method according to claim 12, further comprising a display step of displaying the predetermined value on a screen. 14. The operation according to claim 12, wherein the warning step includes at least one of a step of displaying the verification result on a screen and a step of outputting a sound based on the verification result. Control method. 15. The operation control method according to claim 12, further comprising an extraction step of extracting the predetermined value from a predetermined area of the photographed image. 16. The operation control method according to claim 15, wherein the predetermined area includes a subject area to be photographed. 17. The operation control method according to claim 15, wherein said extracting step includes a step of extracting a maximum pixel value in said predetermined area as said predetermined value. 18. The method according to claim 15, wherein the extracting step includes a step of extracting the predetermined value based on a histogram analysis result of pixel values of the photographed image.
The described operation control method. 19. The captured image includes an image obtained by radiographic imaging, and the extracting step includes removing a through area from the captured image and an area in contact with the through area at regular intervals. 16. The operation control method according to claim 15, comprising: a step; and a step of extracting the predetermined value from the image after the pass-through deletion in the step. 20. The operation control method according to claim 12, wherein the photographed image includes an image obtained by radiographing a lung as a subject. 21. A storage medium, wherein the processing steps of the operation control method according to claim 12 are stored in a computer readable manner.