JP2011087781A - Image processor and image processing system - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an image processor and an image processing system, capable of executing quick and appropriate defective pixel correction corresponding to various kinds of photographing. <P>SOLUTION: The image processor includes: a storage part 52 for storing two or more kinds of defective pixel maps a, b, c, ... corresponding to the charge storage time; and a control part 51 for extracting the defective pixel maps a, b, c, ... corresponding to the charge storage time of a radiation image forming apparatus 2 from the storage part 52 and correcting defective pixels in the radiation image forming apparatus 2 using the defective pixel maps a, b, c, and so on. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to an image processing apparatus and an image processing system.

  2. Description of the Related Art Conventionally, as a means for acquiring a medical radiographic image, a radiographic image forming apparatus in which a solid-state imaging device called a so-called flat panel detector (FPD) is two-dimensionally arranged is known. In such a radiation image forming apparatus, the radiation energy is directly converted into charges using a photoconductive material such as a-Se (amorphous selenium) as a radiation detection element, and the charges are arranged two-dimensionally. A direct readout method that reads out electrical signals in pixel units by switching elements for signal readout, such as TFT (Thin Film Transistor), or radiation energy is converted into light by a scintillator, and this light is arranged two-dimensionally. It is known that there is an indirect type that is converted into electric charge by a photoelectric conversion element such as a photodiode and read out as an electric signal by a TFT or the like.

  In an FPD-type radiation image forming apparatus, pixels that output abnormal image data constantly or with a certain probability due to impurities mixed into the image sensor when the image sensor is laminated on a sensor panel. (Hereinafter referred to as a defective pixel) may occur.

When such a defective pixel exists, an image defect occurs in that portion, and a high-definition image cannot be obtained.
Therefore, conventionally, when shooting is performed using a sensor panel having defective pixels, simple average interpolation is performed using pixel values of normal pixels in the vicinity of the defective pixels, weighted average interpolation is performed, etc. Interpolation processing for interpolating pixel values of defective pixels has been performed by this method.

In order to correct a defective pixel, it is necessary to specify the position of the defective pixel, and a radiation image forming apparatus having means for registering a pixel that outputs an inconsistent output signal as a defective pixel has been proposed (for example, Patent Document 1).
It is also conceived that the position of such a defective pixel is registered in advance to generate a defective pixel map, the position of the correction target pixel is specified using this map, and correction processing is performed.

JP 2000-135210 A

  However, some pixels function normally when the charge accumulation time is short, but they exhibit unstable behavior when the charge accumulation time is long. To increase.

For this reason, if a defective pixel map corresponding to a case where the charge accumulation time is short is prepared, defective pixels that cannot be corrected are generated when photographing with a long charge accumulation time is performed.
On the other hand, if a defective pixel map corresponding to the case where the charge accumulation time is long regardless of the length of the charge accumulation time is used to correct a pixel that exhibits unstable behavior when the charge accumulation time is long, the charge accumulation time is When it is short, normal pixels are corrected, and there is a problem that the image quality deteriorates and the correction speed decreases.

  The present invention has been made in view of the circumstances as described above, and an object thereof is to provide an image processing apparatus and an image processing system capable of performing quick and appropriate defective pixel correction in response to various shootings. It is what.

In order to solve the above problems, an image processing apparatus according to the present invention provides:
Radiation image formation that includes a detection unit in which a plurality of radiation detection elements constituting a pixel are arranged in a two-dimensional matrix, reads out the charges accumulated in the radiation detection elements, and forms an image corresponding to the accumulated charge amount An image processing apparatus for correcting defective pixels in the apparatus,
Map storage means for storing a plurality of types of defective pixel maps according to charge accumulation time;
Map extraction means for extracting the defective pixel map according to the charge accumulation time of the radiation image forming apparatus from the map storage means;
Defective pixel correction means for correcting defective pixels in the radiation image forming apparatus using the defective pixel map extracted by the map extraction means;
It is characterized by having.

In addition, an image processing system according to another aspect of the present invention is as follows.
Radiation image formation that includes a detection unit in which a plurality of radiation detection elements constituting a pixel are arranged in a two-dimensional matrix, reads out the charges accumulated in the radiation detection elements, and forms an image corresponding to the accumulated charge amount Equipment,
Map storage means for storing a plurality of types of defective pixel maps;
Map extraction means for extracting the defective pixel map according to the charge accumulation time of the radiation image forming apparatus from the map storage means;
Defective pixel correction means for correcting defective pixels in the radiation image forming apparatus using the defective pixel map extracted by the map extraction means;
It is characterized by having.

  According to the present invention, by properly using a plurality of types of defect maps according to the charge accumulation time, even if the charge accumulation time is long, pixels that exhibit unstable behavior due to long-time charge accumulation are corrected as defective pixels. In addition, when the charge accumulation time is short, only pixels that are abnormal during the charge accumulation time can be corrected, and image quality deterioration can be prevented and correction processing can be performed quickly.

It is a schematic diagram showing an example of a system configuration of an image processing system in this embodiment. 1 is a perspective view showing an appearance of a radiation image forming apparatus applied to an image processing system according to the present embodiment. FIG. 3 is an equivalent circuit diagram illustrating configurations of a sensor panel unit, a reading unit, and the like of the radiographic image forming apparatus illustrated in FIG. 2. It is a principal part block diagram which shows the functional structure of the console shown in FIG.

  Hereinafter, preferred embodiments of the present invention will be described with reference to the drawings. Note that embodiments to which the present invention is applicable are not limited to this.

  First, a first embodiment of an image processing apparatus according to the present invention and an image processing system including the same will be described with reference to FIGS. 1 to 4. However, the present invention is not limited to the illustrated example.

FIG. 1 is a schematic diagram illustrating a schematic configuration of an image processing system according to the present embodiment.
The image processing system is a system applied in radiographic imaging performed in a hospital, and includes a radiographic image forming apparatus 2 that obtains radiographic image data (hereinafter simply referred to as “image data”), and the radiographic image forming apparatus. 2 and a console 5 as an image processing apparatus capable of communicating with the computer 2.
The console 5 is connected to a wireless local area network (LAN) 8. Similarly, a wireless access point 113 (described later) connected to the wireless LAN 8, a data relay server 116, and a data management server 7 (described later) such as PACS. It is possible to send and receive information with a wireless system.

As shown in FIG. 1, the radiographic image forming apparatus 2 is provided in an imaging room R1 that performs imaging of a subject (an imaging target site of the patient H), for example, by irradiating radiation. The console 5 is provided corresponding to the photographing room R1.
In the present embodiment, a case where one imaging room R1 is provided in the image processing system and one radiation image forming apparatus 2 is arranged in the imaging room R1 will be described as an example. The number of rooms and the number of radiation image forming apparatuses 2 provided in each imaging room are not limited to the illustrated example.
Further, when there are a plurality of shooting rooms R1, the consoles 5 do not have to be provided corresponding to the respective shooting rooms R1, and even if one console 5 is associated with the plurality of shooting rooms R1. Good.

In the radiographing room R1, a bucky device 110 having a cassette holding unit 111 capable of loading and holding the radiographic image forming apparatus 2, and a radiation source such as an X-ray tube that irradiates a subject (imaging target region of the patient H) A radiation generator 112 is provided which comprises (not shown). The cassette holding unit 111 is for loading the radiation image forming apparatus 2 at the time of imaging.
Although FIG. 1 illustrates the case where one bucky device 110 for standing-up shooting is provided in the shooting room R1, the number and types of the bucky devices 110 provided in the shooting room R1 are particularly limited. It is not limited. For example, the bucky device 110 may be a bucky device for standing position shooting, or may be provided with a bucky device for standing position shooting and a bucky device for position shooting. Further, when there are a plurality of the bucky devices 110, one radiation generation device 112 may be provided corresponding to each of the bucky devices 110, or one radiation generation device 112 is provided in the imaging room R1, One radiation generation device 112 may correspond to the plurality of bucky devices 110, and may be used by appropriately moving the position or changing the radiation irradiation direction.

In addition, since the radiographing room R1 is a room that shields radiation and radio waves for radio communication are also blocked, the radiographic image forming apparatus 2 and an external device such as the console 5 communicate in the radiographing room R1. Are provided with a wireless access point (base station) 113 for relaying these communications.
The wireless access point 113 is connected to a wireless LAN (Local Area Network) 8 in the facility by a LAN cable or the like, and can communicate with each device provided outside the photographing room R1.

In the radiographing room R1, a signal repeater 116 that relays transmission / reception of signals between the radiation generating apparatus 112 and another apparatus such as the radiation image forming apparatus 2 and the console 5 is provided. The signal repeater 116 is connected to the wireless LAN 8 in the facility by a LAN cable or the like.
The signal repeater 116 functions as a conversion device that converts, for example, a signal output from the radiation generator 112 into a signal for LAN communication suitable for a general HUB or the like. The radiographic image forming apparatus 2 and the console 5 and the radiation generating apparatus 112 can transmit and receive signals via the signal repeater 116. For example, the exposure timing and the reset timing of the radiographic image forming apparatus 2 are linked. The irradiation field, tube position, and the like can be linked in accordance with shooting.

  In the present embodiment, a front room R2 is provided adjacent to the photographing room R1. In the anterior chamber R2, an operation device 115 including an exposure button (not shown) of a radiation generator 112 that radiates radiation onto a subject is provided by a radiologist, a doctor, or the like (hereinafter referred to as an “operator”). Yes. The operation device 115 is connected to the radiation generation device 112 via a cable or the like. When an engineer operates the exposure button in hope of starting imaging, a signal indicating that the exposure button has been pressed is sent to the radiation generation device 112. And is further transmitted from the radiation generator 112 to the console 5 or the like via the signal relay 116.

  Note that a control signal for controlling the radiation irradiation conditions of the radiation generation apparatus 112 may be transmitted from the console 5 to the operation device 115. In this case, the radiation irradiation condition of the radiation generator 112 is set according to the control signal from the console 5 transmitted to the operation device 115. Examples of radiation irradiation conditions include exposure start / end timing, radiation tube current value, radiation tube voltage value, filter type, and the like.

In the present embodiment, the radiation image forming apparatus 2 is a cassette type FPD in which a so-called flat panel detector (hereinafter referred to as “FPD”) is configured to be portable, and is used for radiographic imaging to detect radiation. Thus, radiation image data corresponding to the radiation dose (hereinafter simply referred to as “image data”) is generated and acquired.
In the following, a so-called indirect radiation image forming apparatus that includes a scintillator or the like and converts the emitted radiation into electromagnetic waves of other wavelengths such as visible light to obtain an electrical signal will be described as the radiation image forming apparatus 2. However, the present invention can also be applied to a so-called direct type radiation image forming apparatus that directly detects radiation with a radiation detection element without using a scintillator or the like.

FIG. 2 is a perspective view of the radiation image forming apparatus 2 in the present embodiment.
As shown in FIG. 2, the radiation image forming apparatus 2 includes a housing 21 that protects the inside. The housing 21 has at least a surface X on which radiation is received (hereinafter referred to as a radiation incident surface X) formed of a material such as a carbon plate or plastic that transmits radiation. FIG. 2 shows a case where the casing 21 is formed of a front member 21a and a back member 21b. However, the shape and configuration are not particularly limited. It is also possible to form a cylindrical so-called monocoque shape.

  As shown in FIG. 2, in the present embodiment, a power switch 22, an indicator 25, a connection portion 26, and the like are disposed on the side surface portion of the radiation image forming apparatus 2.

  The power switch 22 switches ON / OFF of the power supply of the radiation image forming apparatus 2, and by operating the power switch 22, start and stop of power supply to each functional unit of the radiation image forming apparatus 2 by a battery. The instructing signal is output to the control unit 30 (see FIG. 3) described later. When the radiographic image forming apparatus 2 is not used for imaging, the power consumption of the battery can be suppressed by turning off the power (that is, stopping the power supply to each functional unit by the battery).

The indicator 25 is composed of, for example, an LED or the like, and displays the remaining charge amount of the battery, various operation states, and the like.
In the present embodiment, for example, it performs a function of notifying the operator of the completion of the reset operation by blinking when the reset is completed.

The radiographic image forming apparatus 2 is provided with a battery (not shown) that supplies power to each functional unit of the radiographic image forming apparatus 2.
The battery can be charged, for example, a rechargeable secondary battery such as a nickel cadmium battery, a nickel metal hydride battery, a lithium ion battery, a small sealed lead battery, a lead storage battery, an electric double layer capacitor, a lithium ion capacitor (LIC). A power storage element or the like can be applied.
Among these, a lithium ion capacitor is particularly preferable because it is excellent in power storage efficiency, can be charged at high speed with a large current (for example, 5 to 10 A), and can greatly shorten the charging time.

  Further, a lid member 70 that is opened and closed for replacement of a battery built in the housing 21 is provided on a side surface portion of the radiation image forming apparatus 2, and a radiation image is disposed on a side surface portion of the lid member 70. An antenna device 71 is embedded in which the forming apparatus 2 transmits and receives information to and from the outside via a wireless access point 113 (see FIG. 1) described later.

  The connection unit 26 is a connection unit for connecting a power supply cable (not shown) for charging the battery or an external power supply terminal. The connection unit 26 may be capable of connecting a communication cable (not shown) when performing communication by a wired method in addition to a power feeding cable or the like.

A scintillator layer (not shown) that absorbs radiation incident from the radiation incident surface X and converts it into light having a wavelength including visible light is formed inside the radiation incident surface X (see FIG. 2) of the housing 21. As the scintillator layer, for example, a layer formed by using a phosphor in which a luminescent center substance is activated in a mother body such as CsI: Tl, Gd ₂ O ₂ S: Tb, ZnS: Ag, or the like can be used.

  A plurality of photoelectric conversion elements 23 (see FIG. 3) that convert light output from the scintillator layer into electric signals are two-dimensionally provided on the surface of the scintillator layer opposite to the surface on which radiation is incident. A sensor panel unit 24 as an arrayed detection unit is provided. The photoelectric conversion element 23 is, for example, a photodiode, and constitutes a radiation detection element that converts the radiation transmitted through the subject into an electrical signal together with the scintillator layer and the like.

  In the present embodiment, a reading unit 45 (see FIG. 3) that is a reading unit that reads the output value of each photoelectric conversion element 23 of the sensor panel unit 24 by the control unit 30, the scanning drive circuit 32, the signal reading circuit 33, and the like. Is configured.

The configurations of the sensor panel unit 24 and the reading unit 45 will be further described with reference to the equivalent circuit diagram of FIG.
As shown in FIG. 3, one electrode of each photoelectric conversion element 23 of the sensor panel unit 24 is connected to a source electrode of a TFT 46 which is a signal reading switch element. In addition, a bias line Lb is connected to the other electrode of each photoelectric conversion element 23, and the bias line Lb is connected to a bias power supply 36, and a reverse bias voltage is applied from the bias power supply 36 to each photoelectric conversion element 23. It has come to be.

  The gate electrode of each TFT 46 is connected to a scanning line Ll extending from the scanning drive circuit 32, and a read voltage (ON voltage) or OFF voltage is applied to the gate electrode of the TFT 46 from a TFT power source (not shown) via the scanning line Ll. Is applied. The drain electrode of each TFT 46 is connected to the signal line Lr. Each signal line Lr is connected to an amplifier circuit 37 in the signal readout circuit 33, and an output line of each amplifier circuit 37 is connected to an analog multiplexer 39 via a sample hold circuit 38. The signal readout circuit 33 is connected to an A / D converter 40 as processing means for converting the signal into a digital signal. The analog image signal sent from the analog multiplexer 39 is an A / D converter. 40 is converted into a digital image signal. The signal readout circuit 33 is connected to the control unit 30 via the A / D conversion unit 40, and a digital image signal is output to the control unit 30. A storage unit 31 is connected to the control unit 30, and the control unit 30 stores the digital image signal sent from the A / D conversion unit 40 in the storage unit 31 as image data.

  The control unit 30 is a computer including a CPU (Central Processing Unit), a ROM (Read Only Memory), a RAM (Random Access Memory), and the like (not shown), and comprehensively controls the entire radiation image forming apparatus 2.

The ROM stores a program for performing various processes in the radiation image forming apparatus 2 such as an image data generation process and a power supply control process, various control programs, parameters, and the like.
The control unit 30 reads a predetermined program stored in the ROM, develops it in a work area of the RAM, and the CPU executes various processes according to the program.

  In addition to generating image data, the control unit 30 performs conversion processing of image data that is converted into data in a format suitable for outputting image data to the outside by performing predetermined signal processing on the image data.

In the present embodiment, the control unit 30 controls the communication unit to perform communication with the corresponding console 5 via the wireless access point 113.
When the reset process of the radiation image forming apparatus 2 is completed, the control unit 30 transmits a reset completion signal to that effect to the corresponding console 5.

  The storage unit 31 is configured by, for example, an HDD (Hard Disk Drive), a flash memory, or the like. The storage unit 31 includes actual image data generated by the reading unit 45 (see FIG. 3) (radiation transmitted through the subject). Based image data), dark read values (image data of dark images acquired without radiation), and the like are stored.

  The storage unit 31 may be a built-in memory or a removable memory such as a memory card. Further, the capacity is not particularly limited, but preferably has a capacity capable of storing a plurality of pieces of image data. By providing such a storage means, it is possible to continuously irradiate a subject with radiation, and to record and accumulate image data each time, enabling continuous shooting and moving image shooting. Become.

The communication unit is connected to the antenna device 71, and transmits / receives various signals to / from an external device such as the console 5 under the control of the control unit 30. The communication unit communicates with an external device such as the console 5 in a wireless manner via the wireless access point 113.
The communication unit transmits image data based on an image signal read by the reading unit 45 and converted from an analog signal to a digital signal by the A / D conversion unit 40 to the console 5 which is an external device and also photographed from the console 5 or the like. Order information can be received.

  As shown in FIG. 4, the console 5 includes a control unit 51 including a CPU (Central Processing Unit), a storage unit 52, an input unit 53, a display unit 54, a communication unit 55, and the like. Each part is connected by a bus 57.

The storage unit 52 includes a ROM (read only memory), a RAM (Random Access Memory), and the like (not shown).
The ROM is composed of, for example, an HDD (Hard Disk Drive), a semiconductor non-volatile memory, or the like. The ROM performs image processing such as gradation processing and frequency processing based on automatic part recognition for detecting an affected area. In addition to storing various programs such as programs for image processing, image processing parameters for adjusting image data of captured images to an image quality suitable for diagnosis (look-up table defining tone curves used for tone processing, Frequency processing emphasis degree, etc.) are stored.
The RAM forms a work area that temporarily stores various programs, input or output data, parameters, and the like that are read from the ROM and executed by the control unit 51 in various processes that are executed and controlled by the control unit 51. . In the present embodiment, the RAM temporarily stores image data, patient information, and the like received from the radiation image forming apparatus 2.
In the present embodiment, the storage unit 52 stores shooting order information and the like. The storage unit 52 functions as an image data storage unit that temporarily stores the image data transmitted from the radiation image forming apparatus 2. Furthermore, the storage unit 52 also functions as a storage unit that stores offset correction value information and gain correction value information of the radiation image forming apparatus 2 used for imaging.

In the present embodiment, the storage unit 52 is a map storage unit that stores a plurality of defective pixel maps. Here, the defective pixel map is a map in which pixel positions of defective pixels in the radiation image forming apparatus 2 are stored.
In order to perform defective pixel correction processing, the pixel position of the defective pixel must be known in advance. Such defective pixels are detected by performing post-manufacturing shipping inspections or inspections involving radiation irradiation during regular calibration, and the pixel positions of the detected defective pixels are registered in the defective pixel map. When the console 5 is associated with a plurality of radiation image forming apparatuses 2, a defective pixel map is constructed for each radiation image forming apparatus 2, and thereafter operated in association with each radiation image forming apparatus 2. Managed.

  In this embodiment, as shown in FIG. 4, a plurality of defective pixel maps a, b, c... Are prepared for one radiographic image forming apparatus 2 corresponding to the imaging mode. In the present embodiment, as will be described later, as the imaging mode, a synchronization mode in which the radiation image forming apparatus 2 performs imaging in synchronization with the radiation generation apparatus 112 and an asynchronous in which imaging is performed without synchronization with the radiation generation apparatus 112. In addition, in the asynchronous mode, the long-time mode in which the charge accumulation time is set to be relatively long and the short-time mode in which the charge accumulation time is set to be shorter are used as the shooting modes. It can be selected.

Each imaging mode has different charge accumulation times of the radiation image forming apparatus 2, and a plurality of types of defective pixel maps a, b, c... Are provided according to the length of the charge accumulation time.
That is, for example, in the case of the synchronous mode, the timing of the reset operation by the radiation image forming apparatus 2 and the start of radiation exposure by the radiation generating apparatus 112 are synchronized, and the radiation image forming apparatus 2 Charges can be accumulated in accordance with the start and end timing of the exposure. Therefore, in this case, the radiation image forming apparatus 2 has a charge accumulation time from the start of exposure to the end of exposure by the radiation generator 112 after the end of the reset operation, for example, 1 second or more. The following is a very short time. Therefore, the defective pixel map corresponding to the synchronous mode is, for example, recorded and registered defective pixels detected in a time of 1 second or less.
On the other hand, in the asynchronous mode, since the timing of the start and end of radiation exposure by the radiation generator 112 is unknown, the charge accumulation time is set longer than that in the synchronous mode. In the long time mode of the asynchronous mode, for example, the charge accumulation time is set to about 5 seconds, and in the short time mode, for example, the charge accumulation time is set to about 2 seconds. Therefore, the defective pixel map corresponding to the long-time mode in the asynchronous mode is, for example, recorded / registered defective pixels detected in the charge accumulation time of 5 seconds. The pixel map is, for example, recorded and registered defective pixels detected with a charge accumulation time of 2 seconds.
Each charge accumulation time is an example, and is not limited to this time. The selectable shooting modes are not limited to those exemplified here, and a plurality of shooting modes may be selectable, or only two types of synchronous mode and asynchronous mode may be selected. Defective pixel maps a, b, c... Are prepared corresponding to the charge accumulation times corresponding to the respective photographing modes.

  Even a pixel that functions normally when the charge accumulation time is short may exhibit an unstable behavior in which the signal value greatly fluctuates with each photographing when the charge accumulation time becomes long. In general, it is known that as the charge accumulation time becomes longer, the number of pixels that exhibit such unstable behavior increases, and a pixel that fluctuates beyond a certain threshold for each photographing is registered as a defective pixel in the defective pixel map.

  The method for generating the defective pixel maps a, b, c... Is not particularly limited. For example, a defective pixel is detected and extracted by performing an inspection accompanied by radiation irradiation at the time of shipping inspection after manufacture of the radiation image forming apparatus 2 or periodic calibration, and the pixel position of the detected defective pixel Are registered in the defective pixel map. At this time, for example, when the charge accumulation time is 1 second, when 2 seconds, when 5 seconds, the charge accumulation time is changed, a plurality of inspections are performed, and a defective pixel map corresponding to each charge accumulation time is obtained. Generate.

  The control unit 51 is a control unit of the console 5 that reads out various programs such as a system program and a processing program stored in the ROM, expands them in a work area of the RAM, and executes various processes according to the expanded programs.

The control unit 51 determines whether the photographing is performed in the synchronous mode or the asynchronous mode, and when the photographing is performed in the asynchronous mode, how much time is set as the charge accumulation time, and is stored as map storage means. It functions as a map extraction means for extracting defective pixel maps a, b, c... According to the charge accumulation time input from the input section 53 as setting means and set in the control section 51.
In addition, the control unit 51 functions as a defective pixel correction unit that corrects defective pixels in the radiation image forming apparatus using the extracted defective pixel maps a, b, c.

Further, the control unit 51 accesses the data management server 7 via the wireless LAN 8 and performs imaging from the offset correction value information and gain correction value information of the radiation image forming apparatus 2 stored in the data management server 7. The data corresponding to the radiation image forming apparatus 2 used in the above is read out and acquired. When image data is transmitted from the radiation image forming apparatus 2, the image data is corrected using the offset correction value and gain correction value acquired from the data management server 7.
Further, the control unit 51 controls the display of the display unit 54 so as to display an image based on the image data sent from the radiation image forming apparatus 2.

The control unit 51 determines whether the reset processing of the radiation image forming apparatus 2 has been completed and is in a state suitable for imaging.
Specifically, it is determined whether or not a reset completion signal indicating that the reset process has been completed is received from the radiation image forming apparatus 2.

In the present embodiment, the control unit 51 controls the communication unit 55 so as to output an exposure prohibition signal (interlock signal) so as to maintain an exposure prohibition state with respect to the radiation generator 112. . The exposure prohibition signal (interlock signal) is output to the radiation generator 112 via, for example, a LAN cable and a signal repeater 116 (not shown).
Even if a signal indicating that the exposure button has been operated is transmitted from the radiation generator 112, the control unit 51 does not receive the reset completion signal from the radiation image forming apparatus 2, but the control unit 51 performs the exposure prohibition signal (interlock). Signal) is output and the exposure prohibited state is maintained.

The input unit 53 includes a keyboard having character input keys, numeric input keys, various function keys, and the like, and a pointing device such as a mouse, and a key pressing signal pressed by the keyboard and an operation signal by the mouse. Are output to the control unit 51 as an input signal.
In the present embodiment, the input unit 53 can set a plurality of types of imaging modes having different charge accumulation times for the radiation image forming apparatus 2 and functions as a setting unit that selects and sets a synchronous mode, an asynchronous mode, and the like. .
The input unit 53 functions as input means for inputting subject information (photographing order information) related to the subject, an exposure instruction, and the like.
Note that subject information (imaging order information) registered in advance from a HIS / RIS (not shown) may be sent to the console 5. In this case, subject information (imaging order information) can be acquired without input from the input unit 53.

The display unit 54 includes a monitor such as a CRT (Cathode Ray Tube) or an LCD (Liquid Crystal Display), for example, and displays various screens according to instructions of display signals input from the control unit 51.
A pressure-sensitive (resistive film pressure type) touch panel (not shown) in which transparent electrodes are arranged in a grid pattern is formed on the screen of the display unit 54, and the display unit 54 and the input unit 53 are configured integrally. It may be a touch screen. In this case, the touch panel is configured to detect the XY coordinates of the power point pressed by a finger, a touch pen, or the like as a voltage value, and output the detected position signal to the control unit 51 as an operation signal. The display unit 54 may have a higher definition than a monitor used in a general PC (Personal Computer).

In the present embodiment, the display unit 54 is a display unit that displays an image based on image data transmitted from the radiation image forming apparatus 2.
Further, the display unit 54 can display a shooting order list based on shooting order information acquired by input from the input unit 53 or the like. When the user selects arbitrary shooting order information from the shooting order list (selects arbitrary shooting order information from the shooting order list on the screen with the input unit 53 such as a mouse), the shooting order information is obtained. You can select and enter.

  The communication unit 55 is connected to the wireless LAN 8 and transmits / receives information to / from the radiation image forming apparatus 2 and the like via the wireless access point 113 provided in the imaging room R corresponding to each console 5.

  In addition to the data management server, the console 5 may be connected to an external device such as a HIS / RIS, an imager, or the like (all not shown) via a network. Note that the external device connected to the console 5 via the network is not limited to the one exemplified here.

Next, the operation of the image processing apparatus and the image processing system in this embodiment will be described.
In imaging using the radiation image forming apparatus 2, when an imaging mode is input from the input unit 53 of the console 5, imaging according to the imaging mode is performed.
Specifically, for example, when the synchronous mode is set, when the radiation engineer or the like operates the exposure button of the operation device 115 in the front chamber R2, the radiation image forming device 2 side performs a reset operation based on this. A signal to the effect that the exposure button has been operated is output from the radiation generator 112 to the console 5 via the signal repeater 116. From the communication unit 55 of the console 5, corresponding imaging via a LAN cable or the like is performed. An exposure prohibition signal (interlock signal) that prohibits exposure is output to the radiation generator 112 in the room R1, and the exposure button of the operation device 115 is operated unless the exposure prohibition signal is canceled. Even in this case, the state where the radiation generator 112 is prohibited from being exposed is maintained. And the control part 51 of the console 5 judges whether the reset completion signal was received from the radiographic image forming apparatus 2 used for imaging | photography, and when not receiving a reset completion signal, output of an exposure prohibition signal Is not released, and the radiation generator 112 is kept from being exposed to radiation. On the other hand, when the reset completion signal is received, the output of the exposure prohibition signal to the radiation generator 112 is canceled. Thereby, radiation is exposed from the radiation generator 112 and imaging is performed.
For example, when the asynchronous mode is set to the long-time mode, the radiation image forming apparatus 2 performs a reset operation, and when the reset operation is completed, notifies the operator of the completion of the reset operation by blinking the indicator 25 or the like. Then, the charge accumulation state is entered for 5 seconds after the reset operation is completed. The operator confirms that the indicator of the radiation image forming apparatus 2 has blinked, and operates the exposure button on the operation device 115 or the like. As a result, the interlock is released, radiation is emitted from the radiation generator 112, and imaging is performed.
When imaging is performed, the image data acquired thereby is appropriately transmitted from the radiation image forming apparatus 2 to the console 5.

When image data is sent from the radiation image forming apparatus 2, the console 5 extracts a defective pixel map corresponding to the charge accumulation time in the set imaging mode from the storage unit 52.
For example, among the defective pixel maps a, b, c... Shown in FIG. 4, the defective pixel map a is a map in which defective pixels are recorded when the charge accumulation time corresponding to the synchronous mode is 1 second. b is a map in which defective pixels are recorded when the charge accumulation time is 5 seconds corresponding to the long-time mode of the asynchronous mode, and the defective pixel map c is a map when the charge accumulation time is 2 seconds corresponding to the short-time mode of the synchronous mode. Assuming that the map is a map in which defective pixels are recorded, the defective pixel map a is extracted when the set shooting mode selected in shooting is the synchronous mode. Further, when the long-time mode of the asynchronous mode is set, the defective pixel map b is extracted.
Then, defective pixel correction is performed on the image data sent from the radiation image forming apparatus 2 using any of the extracted defective pixel maps a, b, c.
Furthermore, an offset correction value, gain correction value information, and the like corresponding to the radiation image forming apparatus 2 are acquired from the data management server 7 and the like, and image processing such as offset correction and gain correction is appropriately performed.

  When various corrections and image processing are completed, an image based on the image data after the correction processing and image processing is displayed on the display unit 54 of the console 5.

As described above, according to the present embodiment, a plurality of types of defective pixel maps a, b, c... According to the charge accumulation time are prepared, and according to the set charge accumulation time of the photographing mode. Any defective pixel map a, b, c... Is extracted, and defective pixels are corrected according to this map.
Some pixels function normally when the charge accumulation time is short, but some of them exhibit unstable behavior as the charge accumulation time increases, and the number of pixels that are determined to be defective pixels increases as the charge accumulation time increases. . However, in order to correct such a pixel, if a defective pixel map corresponding to the case where the charge accumulation time is long regardless of the length of the charge accumulation time is used, the normal pixel is corrected when the charge accumulation time is short. As a result, the image quality deteriorates and the correction speed decreases.
In this regard, by properly using a plurality of types of defective pixel maps a, b, c... According to the charge accumulation time, pixels that exhibit unstable behavior due to long-time charge accumulation when the charge accumulation time is long. Can also be corrected as defective pixels, and when the charge accumulation time is short, only pixels that are abnormal in the charge accumulation time can be corrected, preventing deterioration in image quality and promptly performing correction processing. It can be carried out.
In the case of the asynchronous mode, the long time mode and the short time mode can be selected according to the situation, so that various shootings can be flexibly handled.

In the present embodiment, the case where the charge accumulation time is set in advance in the asynchronous mode has been described as an example, but the start of radiation exposure by the radiation generator 112 is detected, and the charge accumulation state is transitioned. In the case of the radiation image forming apparatus 2 that detects the end of radiation exposure and transitions to the charge readout state, the time from the start of the exposure to the end of exposure may be calculated as the charge accumulation time. it can. In this case, the control unit 30 of the radiation image forming apparatus 2 functions as the calculation unit of the present invention. Then, the radiation image forming apparatus 2 transfers the calculated charge accumulation time to the console 5.
The console 5 can extract a defective pixel map corresponding to the transferred charge accumulation time, and use this to correct a defective pixel in the radiation image forming apparatus 2.
For the detection of the start and end of radiation exposure, for example, a known method described in JP-A-9-131337, US7, 211, 803 or the like can be used.
Only the start and end times of radiation exposure may be transferred from the radiation image forming apparatus 2 to the console 5, and the charge accumulation time may be calculated in the console 5. In this case, the control unit 51 of the console 5 functions as calculation means of the present invention.

  In the present embodiment, the radiographic image forming apparatus 2 and the console 5 transmit and receive information using the wireless LAN 8, but the communication method between the radiographic image forming apparatus 2 and the console 5 is wireless. It is not limited to LAN.

  In the present embodiment, offset correction value information, gain correction value information, and the like for each radiation image forming apparatus 2 may be held and managed by the data management server 7, or stored in the storage unit 52 of the console 5. Offset correction value information, gain correction value information, and the like for each forming apparatus 2 may be stored.

  In the present embodiment, the operation device 115 provided in the front chamber R2 is described as an example where the exposure button of the radiation generation device 112 is provided. However, the exposure button of the radiation generation device 112 is the operation device. 115 is not limited thereto. For example, an exposure button may be provided on the console 5.

  In addition, it goes without saying that the present invention is not limited to the present embodiment and can be appropriately changed.

2 Radiation image forming apparatus 5 Console 7 Data management server 24 Sensor panel unit 25 Indicator 26 Connection unit 30 Control unit 51 Control unit 52 Storage unit R1 Imaging room

Claims (4)

Radiation image formation that includes a detection unit in which a plurality of radiation detection elements constituting a pixel are arranged in a two-dimensional matrix, reads out the charges accumulated in the radiation detection elements, and forms an image corresponding to the accumulated charge amount An image processing apparatus for correcting defective pixels in the apparatus,
Map storage means for storing a plurality of types of defective pixel maps according to charge accumulation time;
Map extraction means for extracting the defective pixel map according to the charge accumulation time of the radiation image forming apparatus from the map storage means;
Defective pixel correction means for correcting defective pixels in the radiation image forming apparatus using the defective pixel map extracted by the map extraction means;
An image processing apparatus comprising: It is possible to set at least a synchronous mode in which the radiation image forming apparatus operates in synchronization with a radiation generating apparatus that generates radiation, and an asynchronous mode in which the radiation image forming apparatus operates without synchronizing with the radiation generating apparatus. Yes,
The image processing apparatus according to claim 1, wherein the asynchronous mode sets a longer charge accumulation time of the radiation image forming apparatus than the synchronous mode. Radiation image formation that includes a detection unit in which a plurality of radiation detection elements constituting a pixel are arranged in a two-dimensional matrix, reads out the charges accumulated in the radiation detection elements, and forms an image corresponding to the accumulated charge amount Equipment,
Map storage means for storing a plurality of types of defective pixel maps;
Map extraction means for extracting the defective pixel map according to the charge accumulation time of the radiation image forming apparatus from the map storage means;
Defective pixel correction means for correcting defective pixels in the radiation image forming apparatus using the defective pixel map extracted by the map extraction means;
An image processing system comprising: The radiation image forming apparatus detects the start of radiation exposure and transitions to a charge accumulation state, detects the end of radiation exposure and transitions to a charge readout state,
The image processing system according to claim 3, further comprising a calculation unit that calculates a charge accumulation time of the radiation image forming apparatus based on a time from the start of the exposure to the end of the exposure.

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