Radiation image processing device, radiation image processing system, radiation image processing method, and computer-readable recording medium storing program

Abstract

Provided are a radiographic image processing device, a radiographic image processing system, a radiographic image processing method, and a computer-readable recording medium in which a program is stored, with which it is possible to obtain a composite image in which radiographic reading can be facilitated. A console (30) functioning as a radiographic image processing device is provided with: a control unit (31) functioning as an image acquisition unit that acquires a plurality of radiographic images captured by a subject under different imaging conditions; a pixel value correction unit that corrects a pixel value of at least one radiation image among the plurality of radiation images; and an image processing unit (36) that functions as an image synthesis unit that synthesizes a plurality of radiation images, each of which has an image overlapping region with at least one other radiation image, to acquire one synthesized image. The pixel value correction unit corrects the pixel values such that the maximum value of the pixel values of at least one radiation image is equal to or less than the maximum value of the gradation of the image.

Description

Technical Field

[0001] This invention relates to a radiation image processing apparatus, a radiation image processing system, a radiation image processing method, and a computer-readable recording medium containing a program. Background Technology

[0002] Previously, methods for creating composite images by combining multiple images obtained by changing the irradiation direction of a radiation source in the body axis direction (so-called head-shaking ruler) were known.

[0003] In this method, the subject needs to be irradiated with radiation multiple times. Therefore, there is a possibility of adverse health effects on the subject. Therefore, for example, Patent Documents 1 and 2 describe methods that suppress the effects of irradiation by changing the photographic conditions for each image capture and automatically correcting the pixel values ​​of each image during image synthesis.

[0004] Existing technical documents

[0005] Patent documents

[0006] Patent Document 1: Japanese Patent No. 5759405

[0007] Patent Document 2: Japanese Patent No. 4754812 Summary of the Invention

[0008] However, patent documents 1 and 2 do not describe specific methods for pixel value correction. Therefore, the pixel values ​​in the synthesized image may exceed the maximum grayscale value, causing (so-called density saturation) black spots, making image reading difficult.

[0009] The present invention was made in view of the above circumstances. Its object is to provide a radiographic image processing apparatus, a radiographic image processing system, a radiographic image processing method, and a computer-readable recording medium storing a program, capable of obtaining a composite image that facilitates image reading.

[0010] To address the above-mentioned problems, the invention described in technical solution 1 is a radiation image processing device, comprising:

[0011] The image acquisition unit acquires multiple radiographic images of the subject taken under different photographic conditions;

[0012] A pixel value correction unit corrects the pixel values ​​of at least one of the plurality of radiation images; and

[0013] The image synthesis unit combines the multiple radiation images to obtain a composite image.

[0014] Each of the plurality of radiation images has an image region that overlaps with at least one other radiation image.

[0015] The pixel value correction unit corrects the pixel value in such a way that the maximum value of the pixel value of the at least one radiation image becomes less than or equal to the maximum value of the grayscale of the image.

[0016] The invention described in technical solution 2 is based on the radiation image processing apparatus described in technical solution 1.

[0017] Equipped with a photography condition acquisition unit that obtains mAs values ​​from multiple photography conditions,

[0018] The pixel value correction unit corrects the pixel values ​​of the at least one radiation image based on the mAs value.

[0019] The invention described in technical solution 3 is based on the radiation image processing apparatus described in technical solution 2.

[0020] The pixel value correction unit uses the pixel value of the radiation image with the lowest mAs value among the plurality of radiation images as a benchmark to correct the pixel values ​​of the other radiation images.

[0021] The invention described in technical solution 4 is based on the radiation image processing apparatus described in technical solution 1.

[0022] When the pixel value correction unit finds that the pixel value of the at least one radiation image becomes a decimal after correction, it makes the pixel value of all radiation images an integer by making the pixel value of all radiation images a predetermined coefficient multiple.

[0023] The invention described in technical solution 5 is based on the radiation image processing apparatus described in technical solution 1.

[0024] The system includes a display control unit that enables the display unit to display the composite image and the plurality of radiation images.

[0025] The display control unit causes the display unit to display, in a recognizable manner, a radiation image that serves as a reference for correcting the pixel values ​​of at least one radiation image using the pixel value correction unit.

[0026] The invention described in technical solution 6 is a radiation image processing system, which includes:

[0027] The radiation image processing apparatus according to any one of technical solutions 1 to 5;

[0028] Radiation generating device, which generates radiation; and

[0029] A radiographic device that generates a radiographic image by receiving radiation emitted by the radiation generating device.

[0030] The invention described in technical solution 7 is a method for processing radiographic images, comprising:

[0031] The image acquisition step involves acquiring multiple radiation images of the subject taken under different photographic conditions.

[0032] A pixel value correction step corrects the pixel values ​​of at least one of the plurality of radiation images; and

[0033] In the image compositing step, the multiple radiation images are combined to obtain a composite image.

[0034] Each of the plurality of radiation images has an image region that overlaps with at least one other radiation image.

[0035] In the pixel value correction step, the pixel values ​​are corrected in such a way that the maximum value of the pixel values ​​of the at least one radiation image becomes less than or equal to the maximum value of the grayscale of the image.

[0036] The invention described in technical solution 8 is based on the radiation image processing method described in technical solution 7.

[0037] The photography condition acquisition step includes obtaining mAs values ​​from multiple photography conditions.

[0038] In the pixel value correction step, the pixel values ​​of the at least one radiation image are corrected according to the mAs value.

[0039] The invention described in technical solution 9 is based on the radiation image processing method described in technical solution 8.

[0040] In the pixel value correction step, the pixel value of the radiation image with the lowest mAs value among the plurality of radiation images is used as a benchmark to correct the pixel values ​​of the other radiation images.

[0041] The invention described in technical solution 10 is based on the radiation image processing method described in technical solution 7.

[0042] In the pixel value correction step, if the pixel value of the at least one radiation image becomes a decimal after correction, the pixel values ​​of all radiation images are made integers by making the pixel values ​​of all radiation images a predetermined coefficient multiple.

[0043] The invention described in technical solution 11 is based on the radiation image processing method described in technical solution 7.

[0044] The system includes a display control step that causes the display unit to display the composite image and the plurality of radiation images.

[0045] In the display control step, the display unit displays, in a recognizable manner, a radiation image that serves as a reference for correcting the pixel values ​​of at least one radiation image through the pixel value correction step.

[0046] The invention described in technical solution 12 is a computer-readable recording medium storing a program.

[0047] This program enables the computer of the radiographic image processing device to function as a component in the following way:

[0048] The image acquisition unit acquires multiple radiographic images of the subject taken under different photographic conditions;

[0049] A pixel value correction unit corrects the pixel values ​​of at least one of the plurality of radiation images; and

[0050] The image synthesis unit combines the multiple radiation images to obtain a composite image, wherein...

[0051] Each of the plurality of radiation images has an image region that overlaps with at least one other radiation image.

[0052] The pixel value correction unit corrects the pixel value in such a way that the maximum value of the pixel value of the at least one radiation image becomes less than or equal to the maximum value of the grayscale of the image.

[0053] The invention described in technical solution 13 is stored in a computer-readable recording medium containing a program, as described in technical solution 12.

[0054] This enables the computer to function as a photography condition acquisition unit, obtaining mAs values ​​from multiple photography conditions.

[0055] The pixel value correction unit corrects the pixel values ​​of the at least one radiation image based on the mAs value.

[0056] The invention described in technical solution 14 is stored in a computer-readable recording medium containing a program, as described in technical solution 13.

[0057] The pixel value correction unit uses the pixel value of the radiation image with the lowest mAs value among the plurality of radiation images as a benchmark to correct the pixel values ​​of the other radiation images.

[0058] The invention described in technical solution 15 is stored in a computer-readable recording medium containing a program, as described in technical solution 12.

[0059] When the pixel value correction unit finds that the pixel value of the at least one radiation image becomes a decimal after correction, it makes the pixel value of all radiation images an integer by making the pixel value of all radiation images a predetermined coefficient multiple.

[0060] The invention described in technical solution 16 is stored in a computer-readable recording medium containing a program, as described in technical solution 12.

[0061] The computer functions as a display control unit that displays the composite image and the plurality of radiation images on the display unit.

[0062] The display control unit causes the display unit to display, in a recognizable manner, a radiation image that serves as a reference for correcting the pixel values ​​of at least one radiation image using the pixel value correction unit.

[0063] According to the present invention, it is possible to obtain composite images that make image reading easier. Attached Figure Description

[0064] Figure 1 This is a schematic diagram of a radiation image processing system.

[0065] Figure 2 This is a block diagram of the console.

[0066] Figure 3 This is a flowchart of the process for obtaining and processing composite images.

[0067] Figure 4 This is an example diagram showing multiple radiation images.

[0068] Figure 5 This is a diagram showing an example of a composite image.

[0069] Figure 6 This is a diagram showing an example of a display section that displays a composite image.

[0070] Figure 7 This is a diagram illustrating an example of a synthetic image involved in a variant example. Detailed Implementation

[0071] Hereinafter, embodiments of the present invention will be described with reference to the accompanying drawings. However, the scope of the present invention is not limited to the embodiments described below and the examples illustrated in the drawings.

[0072] [Radiation Image Processing System]

[0073] First, the radiation image processing system 100 involved in this embodiment will be described. Figure 1 This is a schematic diagram of a radiation image processing system 100.

[0074] Radiation Image Processing System 100 Figure 1 As shown, the system includes a radiation generating device 10, a radiation imaging device 20, and a control console 30 that serves as a radiation image processing device. The devices constituting the radiation image processing system 100 can be interconnected via, for example, a communication network (LAN, WAN, or the Internet).

[0075] Furthermore, the radiographic image processing system 100 can also be communicatively connected to a system not shown. Examples include HIS (Hospital Information System), RIS (Radiology Information System), or PACS (Picture Archiving and Communication System).

[0076] (Radiation generating device)

[0077] The radiation generating apparatus 10 generates radiation in a pattern corresponding to the type of radiation image. The radiation generating apparatus 10 includes a generator 11, an irradiation switch 12, and a radiation source 13.

[0078] {Generator, Irradiation switch}

[0079] The generator 11 applies a voltage corresponding to the preset imaging conditions to the radiation source 13 according to the operation of the irradiation switch 12.

[0080] {Radiation source}

[0081] The radiation source 13 includes a bulb (not shown), a wire, and the like. The radiation source 13 is positioned facing the radiographic apparatus 20, separated from the subject. When a voltage is applied from the generator 11, the wire irradiates an electron beam corresponding to that voltage towards the rotating anode. The rotating anode irradiates the subject with a dose of radiation (X-rays) corresponding to the intensity of the electron beam. Furthermore, the radiation source 13 can be rotated around a rotation axis parallel to the X-axis, a Y-axis orthogonal to the X-axis, and a Z-axis orthogonal to both the X-axis and Y-axis, thereby changing the orientation of the radiation irradiation port.

[0082] In addition, Figure 1The example shown illustrates a scenario where the generator 11, irradiation switch 12, and radiation source 13 are separate entities, but this is not the only possible embodiment. The generator 11, irradiation switch 12, and radiation source 13 can also be integrated into one unit. Furthermore, the irradiation switch 12 may not be connected to the generator 11, but instead connected to an operating table (not shown). Additionally, the radiation generating device 10 can be a type installed in a radiography room, or it can be a portable type configured to be movable by being assembled into a medical cart, etc.

[0083] (Radiation imaging device)

[0084] The radiography apparatus 20 detects radiation emitted from a radiation source 13 and transmitted through a subject to capture a radiographic image. The radiography apparatus 20 is constructed from an FPD (Flat Panel Detector) or similar device. The radiography apparatus 20 includes, for example, a glass substrate. At predetermined positions on the substrate, the radiography apparatus 20 detects radiation (X-rays) emitted from a radiation generator 10 and transmitted through at least the subject based on their intensity. In the radiography apparatus 20, multiple detection elements (pixels) are arranged in a matrix to convert the detected radiation into electrical signals and store them. Each pixel is configured, for example, to include a switching unit such as a TFT (Thin Film Transistor). Based on image reading conditions input from a control console 30, the radiography apparatus 20 controls the switching units of each pixel to switch on and off to read the electrical signals stored in each pixel, thereby reading the electrical signals stored in each pixel. Through this control, the radiography apparatus 20 acquires image data (frame images). Furthermore, the radiographic imaging device 20 outputs the acquired image data to the control console 30.

[0085] (Console)

[0086] The control console 30 accepts input of imaging conditions set for at least one of the radiation generating apparatus 10 and the radiation imaging apparatus 20. The control console 30 is a dedicated device such as a PC. There are no particular limitations on the method of inputting imaging conditions to the control console 30. For example, it can be any of the following: an operation performed by a user, obtained from another system (HIS, RIS, etc.), or an operation performed by another user (e.g., a technician). The detailed structure of the control console 30 will be described later.

[0087] In the radiation image processing system 100 configured in this way, when the user operates the irradiation indication switch 111, the radiation source 13 irradiates the subject with radiation under the photographic conditions according to the photographic sequence information described later. Moreover, the radiation imaging device 20 located behind the subject receives the radiation transmitted through the subject, reads out the image data, and sends the image data to the control console 30.

[0088] (Detailed structure of the console)

[0089] This section describes the detailed structure of console 30. Figure 2 This is a block diagram of the control console 30. The control console 30 includes a control unit 31, a communication unit 32, a storage unit 33, a display unit 34, an operation unit 35, and an image processing unit 36. Furthermore, all parts of the control console 30 are electrically connected via a bus, etc. The control console 30 functions as a radiographic image processing apparatus that receives various inputs related to the composite image acquisition and processing described later and performs various processing steps.

[0090] {Control Department}

[0091] The control unit 31 consists of a CPU (Central Processing Unit), RAM (Random Access Memory), etc. The CPU reads various programs stored in the storage unit 33 and expands them in the RAM. The CPU executes various processes according to the expanded programs. Through this structure, the control unit 31 centrally controls the operation of each part of the control console 30.

[0092] {Ministry of Communications}

[0093] The communication unit 32 is composed of communication modules and the like. The communication unit 32 transmits and receives various signals and data with other devices such as the radiation generating device 10 and the radiation imaging device 20, which are connected via a communication network.

[0094] {Storage Department}

[0095] The storage unit 33 is composed of non-volatile semi-dynamic memory, hard disk, etc. The storage unit 33 stores various programs executed by the control unit 31, parameters required for program execution, etc. In addition, the storage unit 33 can also store image data of radiation images. Furthermore, the storage unit 33 stores imaging sequence information transmitted from the RIS, etc.

[0096] The imaging sequence information includes information about the patient, the examination details, and the imaging conditions. The examination information includes the examination ID, the imaging site, and the examination date. The imaging conditions include various factors related to the radiation dose irradiated by the radiation generating device 10. These include, for example, the angle of the radiation source 13 (i.e., the imaging site), its positioning (PA, LAT, etc.), tube voltage (kV), tube current (mA), irradiation time (ms), current-time product (mAs value), and the focal-to-radiography device distance (SID).

[0097] {Display Section}

[0098] Display unit 34 displays various images. Display unit 34 may be composed of, for example, LCD (Liquid Crystal Display), ELD (Electronic Luminescent Display), or CRT (Cathode Ray Tube). Display unit 34 displays lists, radiographic images, etc., corresponding to image signals received from control unit 31.

[0099] {Operations Department}

[0100] The operation unit 35 is an operation unit configured for user operation. The operation unit 35 may be a keyboard with cursor keys, numeric input keys, various function keys, an indicator device (such as a mouse), or a touch panel superimposed on the surface of the display unit 34. The operation unit 35 outputs control signals corresponding to the operations performed by the user to the control unit 31.

[0101] {Image Processing Department}

[0102] The image processing unit 36 ​​performs image processing on the radiation image acquired from the radiography device 20. Examples of image processing include dynamic range compression, contrast transformation, LUT (Look Up Table) processing, frequency enhancement, scattering correction, noise suppression, image trimming, image masking, image rotation, and image inversion.

[0103] In particular, the image processing unit 36 ​​functions as a pixel value correction unit, which corrects the pixel values ​​of multiple radiation images acquired from the radiography apparatus 20 in a manner that prevents density saturation. Furthermore, the image processing unit 36 ​​functions as an image compositing unit, which combines the pixel-value-corrected radiation images to generate a single composite image. Details regarding the pixel value correction and image compositing processes will be described later.

[0104] [Image Acquisition and Processing]

[0105] according to Figure 3 The flowchart illustrates the synthetic image acquisition process performed using the radiation image processing system 100 described above.

[0106] The user selects the imaging sequence information of the subject using the operation unit 35 of the control console 30. The communication unit 32 sends the selected imaging sequence information to the radiation generating device 10. After positioning the subject, the user presses the irradiation switch 12. Then, radiation is irradiated from the radiation source 13. The irradiated radiation imaging device 20 reads the radiation image and sends it to the control console 30 (step S101).

[0107] After acquiring the radiation image, the user uses the operation unit 35 to select a different imaging sequence from the previous imaging sequence information (here, step S101). Among these imaging sequence information, at least the angle of the radiation source 13 differs as an imaging condition. The communication unit 32 sends the selected imaging sequence information to the radiation generating device 10. After positioning the subject, the user presses the irradiation switch 12. Radiation is then irradiated from the radiation generating device 10. The irradiated radiation imaging device 20 reads the radiation image and sends it to the control console 30 (step S102).

[0108] The control unit 31, which acquires the second and subsequent radiographic images, displays a confirmation screen on the display unit 34 indicating whether the radiographic imaging is complete, and accepts the user's instruction (step S103). If the radiographic imaging is not complete (step S103; "No"), the user proceeds to step S102, whereby radiographic images are acquired based on imaging sequence information that differs from previous imaging sequence information.

[0109] Upon completion of radiography (step S103; "Yes"), the user instructs the control unit 31 via the operation unit 35 to execute pixel value correction processing and image synthesis processing. The image processing unit 36, receiving the instruction to execute pixel value correction processing, corrects the pixel values ​​based on the actual mAs values ​​in the radiography sequence information (step S104). During pixel value correction processing, the image processing unit 36 ​​corrects the pixel values ​​of each image in a manner that makes the pixel values ​​below the maximum grayscale value (i.e., in a manner that does not cause density saturation).

[0110] As described above, in this step, the image processing unit 36 ​​does not use the set value of mAs, but uses the actual value. Therefore, by setting an AEC (Automatic Exposure Control), even if the dose changes based on the imaging sequence information, processing can be performed to accommodate the change. Furthermore, the actual value of mAs can be obtained from the radiation generating device 10.

[0111] The following, such as Figure 4As shown, two images are acquired from the radiography apparatus 20: a first radiographic image with an mAs value of 3 and a second radiographic image with an mAs value of 6. Both the first and second radiographic images are 16-bit images. Therefore, the maximum grayscale value of both the first and second radiographic images is 65535. Furthermore, as described above, the pixel value of the first radiographic image is between 1000 and 40000. The pixel value of the second radiographic image is between 2000 and 50000.

[0112] At this time, when pixel value correction processing is performed to make the pixel values ​​of the first radiation image match the pixel values ​​of the second radiation image based on the mAs value, the pixel values ​​of the first radiation image become 2000 to 80000, which may cause density saturation. Therefore, in this embodiment, the image processing unit 36 ​​performs pixel value correction processing to make the pixel values ​​of the second radiation image match the pixel values ​​of the first radiation image with the lowest mAs value. As a result, the pixel values ​​of the second radiation image become 1000 to 25000, so density saturation is not caused.

[0113] Furthermore, when correcting pixel values ​​in radiation images to a decimal value, a predetermined coefficient can be set to ensure that all pixel values ​​in all radiation images are integers. This control suppresses rounding errors and concentration deviations.

[0114] After pixel value correction processing, the image processing unit 36, as follows Figure 5 As shown, an image compositing process (step S105) is performed to combine multiple radiation images into a single composite image. Figure 4 as well as Figure 5 As shown, in steps S101 and S102, the user takes a photograph of a radiation image with overlapping regions. Therefore, the image processing unit 36 ​​synthesizes multiple radiation images by overlapping these overlapping regions.

[0115] After generating the composite image, the image processing unit 36 ​​performs grayscale processing to adjust the contrast of the composite image (step S106). The control unit 31 makes the composite image generated by the image processing unit 36 ​​appear as shown in the image. Figure 6 The image is displayed on the display unit 34 (step S107). The user uses the operation unit 35 to appropriately adjust the pixel values ​​and composite position of the displayed composite image (step S108).

[0116] [Effects of the Implementation Method]

[0117] As described above, the control console 30 according to this embodiment includes a control unit 31 that functions as an image acquisition unit, which acquires multiple radiation images of a subject taken under different photographic conditions. Furthermore, the control console 30 includes a pixel value correction unit that corrects the pixel values ​​of at least one radiation image among the multiple radiation images, and an image processing unit 36 ​​that functions as an image compositing unit that combines the multiple radiation images to obtain a composite image. Moreover, the pixel value correction unit corrects the pixel values ​​so that the maximum value of the pixel value of at least one radiation image is below the maximum grayscale value of the image. Therefore, using the control console 30 according to this embodiment, it is possible to suppress the effects of multiple irradiations on the subject while obtaining a composite image that suppresses density saturation and facilitates image reading.

[0118] [Other Structures]

[0119] The embodiments of the present invention have been described in detail above, but the present invention is not limited to the above embodiments. Various modifications are possible, including the scope of the invention as described in the claims and its equivalents.

[0120] For example, the above example illustrates a structure where the image processing unit 36 ​​corrects the pixel values ​​of the second radiation image in a manner that matches the pixel values ​​of the first radiation image with the lowest mAs value, but this is not a limitation. Regarding the pixel value correction processing performed by the image processing unit 36, the specific method is not particularly limited as long as the final synthesized image does not cause density saturation. Therefore, for example, the image processing unit 36 ​​may also correct the pixel values ​​of the first radiation image with a relatively low mAs value in a manner that matches the pixel values ​​of other radiation images with relatively high mAs values.

[0121] Furthermore, the above example illustrates a structure in which the image processing unit 36 ​​uniformly corrects the pixel values ​​of the second radiation image in a manner consistent with the pixel values ​​of the first radiation image, but it is not limited to this. Figure 7 As shown, the image processing unit 36 ​​can also sequentially change the suitability of image processing in other radiation images in the body axis direction.

[0122] Furthermore, the above example illustrates a structure where step S105 of image compositing is performed after step S104 of pixel value correction processing, but it is not limited to this. That is, pixel value correction processing can also be performed after image compositing processing. When this structure is implemented, the user can first check the composite image and determine as early as possible whether re-photographing is needed due to body movement.

[0123] In addition, such as Figure 6As shown, the control unit 31 can also highlight the information in step S107 to indicate which radiation image was used as the reference for pixel value correction processing. Furthermore, in Figure 6 In this context, as an example of emphasis, an identification mark M is assigned, but this is not the only one. For instance, it could also be configured to simply overlap and display a radiographic image serving as a reference.

[0124] Furthermore, step S108 is not limited to manual adjustment of the composite image performed by the operation unit 35. That is, after selecting a radial image as the reference for pixel values, the process can proceed to step S104, whereby the image processing unit 36 ​​performs pixel value correction processing and image compositing processing again. In this case, the user can also select the pixel value processing method performed by the image processing unit 36 ​​from the above types. Alternatively, the user can select the pixel value processing method at the timing of the execution instruction for the pixel value correction processing and image compositing processing immediately following step S104.

[0125] Furthermore, the above description illustrates a structure for storing the photography sequence information obtained from the RIS into the storage unit 33, but it is not limited to this. The photographer can also input the photography sequence information by operating the operation unit 35.

[0126] Furthermore, in the above description, since the multiple radiation images have a density difference, the image processing unit 36 ​​performs pixel value correction processing, but it is not limited to this. That is, for radiation images that serve as a reference and radiation images with approximately the same pixel value, pixel value correction processing can be omitted and composite processing can be performed.

[0127] Furthermore, the above description illustrates a structure for obtaining multiple radiation images by changing the angle of the radiation source 13, but it is not limited to this. It is also possible to configure multiple radiation sources 13 with different irradiation angles, allowing these multiple radiation sources 13 to perform radiation irradiation based on different imaging sequence information, thereby obtaining multiple radiation images at once. When this structure is constructed, deviations in radiation images caused by subject movement between radiation irradiations can be suppressed.

[0128] Furthermore, examples of using hard disks, semiconductor non-volatile memory, etc., as computer-readable media for the program according to the present invention have been disclosed above, but the invention is not limited to these. Other computer-readable media include removable recording media such as CD-ROMs. Additionally, a carrier wave is used as the medium for providing data of the program according to the present invention via a communication line.

[0129] (Symbol Explanation)

[0130] 100: Radiation image processing system; 10: Radiation generating device; 20: Radiation imaging device; 30: Control console (radiation image processing device); 31: Control unit (image acquisition unit, imaging condition acquisition unit, display control unit); 36: Image processing unit (pixel value correction unit, image synthesis unit).

Claims

1. A radiation image processing apparatus, comprising: The image acquisition unit acquires multiple radiographic images of the subject taken under different photographic conditions; A pixel value correction unit corrects the pixel values ​​of at least one of the plurality of radiation images; and The image synthesis unit combines the multiple radiation images to obtain a composite image. Each of the plurality of radiation images has an image region that overlaps with at least one other radiation image. The pixel value correction unit corrects the pixel value in such a way that the maximum value of the pixel value of the at least one radiation image becomes less than or equal to the maximum value of the grayscale of the image.

2. The radiation image processing apparatus according to claim 1, wherein, Equipped with a photography condition acquisition unit that obtains mAs values ​​from multiple photography conditions, The pixel value correction unit corrects the pixel values ​​of the at least one radiation image based on the mAs value.

3. The radiation image processing apparatus according to claim 2, wherein, The pixel value correction unit uses the pixel value of the radiation image with the lowest mAs value among the plurality of radiation images as a benchmark to correct the pixel values ​​of the other radiation images.

4. The radiation image processing apparatus according to claim 1, wherein, When the pixel value correction unit finds that the pixel value of the at least one radiation image becomes a decimal after correction, it makes the pixel value of all radiation images an integer by making the pixel value of all radiation images a predetermined coefficient multiple.

5. The radiation image processing apparatus according to claim 1, wherein, The device includes a display control unit that displays the composite image and the plurality of radiation images on a display unit. The display control unit causes the display unit to display, in a recognizable manner, a radiation image that serves as a reference for correcting the pixel values ​​of at least one radiation image using the pixel value correction unit.

6. A radiation image processing system, comprising: The radiation image processing apparatus according to any one of claims 1 to 5; Radiation generating device, which generates radiation; and A radiographic device that generates a radiographic image by receiving radiation emitted by the radiation generating device.

7. A method for processing radiation images, comprising: The image acquisition step involves acquiring multiple radiation images of the subject taken under different photographic conditions. A pixel value correction step corrects the pixel values ​​of at least one of the plurality of radiation images; and The image compositing step combines the multiple radiation images to obtain a composite image. Each of the plurality of radiation images has an image region that overlaps with at least one other radiation image. In the pixel value correction step, the pixel values ​​are corrected in such a way that the maximum value of the pixel values ​​of the at least one radiation image becomes less than or equal to the maximum value of the grayscale of the image.

8. The radiation image processing method according to claim 7, wherein, The photography condition acquisition step includes obtaining mAs values ​​from multiple photography conditions. In the pixel value correction step, the pixel values ​​of the at least one radiation image are corrected according to the mAs value.

9. The radiation image processing method according to claim 8, wherein, In the pixel value correction step, the pixel value of the radiation image with the lowest mAs value among the plurality of radiation images is used as a benchmark to correct the pixel values ​​of the other radiation images.

10. The radiation image processing method according to claim 7, wherein, In the pixel value correction step, if the pixel value of the at least one radiation image becomes a decimal after correction, the pixel values ​​of all radiation images are made integers by making the pixel values ​​of all radiation images a predetermined coefficient multiple.

11. The radiation image processing method according to claim 7, wherein, The system includes a display control step that causes the display unit to display the composite image and the plurality of radiation images. In the display control step, the display unit displays, in a recognizable manner, a radiation image that serves as a reference for correcting the pixel values ​​of at least one radiation image through the pixel value correction step.

12. A computer-readable recording medium containing a program. This program enables the computer of the radiographic image processing device to function as a component in the following way: The image acquisition unit acquires multiple radiographic images of the subject taken under different photographic conditions; A pixel value correction unit corrects the pixel values ​​of at least one of the plurality of radiation images; and The image synthesis unit combines the multiple radiation images to obtain a composite image, wherein... Each of the plurality of radiation images has an image region that overlaps with at least one other radiation image. The pixel value correction unit corrects the pixel value in such a way that the maximum value of the pixel value of the at least one radiation image becomes less than or equal to the maximum value of the grayscale of the image.

13. The computer-readable recording medium storing a program according to claim 12, wherein, This enables the computer to function as a photography condition acquisition unit, obtaining mAs values ​​from multiple photography conditions. The pixel value correction unit corrects the pixel values ​​of the at least one radiation image based on the mAs value.

14. The computer-readable recording medium storing a program according to claim 13, wherein, The pixel value correction unit uses the pixel value of the radiation image with the lowest mAs value among the plurality of radiation images as a benchmark to correct the pixel values ​​of the other radiation images.

15. The computer-readable recording medium storing a program according to claim 12, wherein, When the pixel value correction unit finds that the pixel value of the at least one radiation image becomes a decimal after correction, it makes the pixel value of all radiation images an integer by making the pixel value of all radiation images a predetermined coefficient multiple.

16. The computer-readable recording medium storing a program according to claim 12, wherein, The computer functions as a display control unit that displays the composite image and the plurality of radiation images on the display unit. The display control unit causes the display unit to display, in a recognizable manner, a radiation image that serves as a reference for correcting the pixel values ​​of at least one radiation image using the pixel value correction unit.

Images