JP2012143474A - Radiation imaging apparatus, and radiation imaging system - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a radiation imaging apparatus and a radiation imaging system capable of increasing compression ratio in compressing image data obtained through radiation imaging.SOLUTION: To create data for compressed and thinned images, the radiation imaging apparatus 1 performs a thinning process in the direction of a signal line at a prescribed rate for data for one image so as to create image for thinned images, creates difference data in the direction of a scanning line for each image data making up the data for the thinned images, and performs a compression process on the difference data. To create data for one compressed image, the radiation imaging apparatus creates difference data in the direction of the signal line for each image data making up the data for the one image, and performs a compression process on the difference data. Also, the radiation imaging apparatus creates data for remaining compressed images, creates difference data in the direction of the signal line for each image data making up data for remaining images after the thinning process, and performs a compression process on the difference data.

Description

  The present invention relates to a radiographic image capturing apparatus and a radiographic image capturing system.

  For the purpose of disease diagnosis and the like, radiographic images taken using radiation typified by X-ray images are widely used. Conventionally, such medical radiographic images have been taken using a screen film. In order to digitize radiographic images, CR (Computed Radiography) devices using stimulable phosphor sheets have been developed recently. Then, a radiation image capturing apparatus has been developed in which irradiated radiation is detected by a radiation detection element arranged in a two-dimensional form and acquired as digital image data.

  As such a radiographic imaging apparatus, a so-called direct type radiographic imaging apparatus that generates a charge in a detection element in accordance with a dose of irradiated radiation such as X-rays and converts it into an electrical signal, or irradiated radiation So-called indirect radiation that is converted into an electric signal by generating electric charges with a photoelectric conversion element such as a photodiode in accordance with the energy of the converted electromagnetic wave Various image photographing apparatuses have been developed. In the present invention, the detection element in the direct type radiographic imaging apparatus and the photoelectric conversion element in the indirect type radiographic imaging apparatus are collectively referred to as a radiation detection element.

  This type of radiographic imaging apparatus is known as an FPD (Flat Panel Detector), and conventionally formed integrally with a support base (or a bucky apparatus) (for example, see Patent Document 1). A portable radiographic imaging apparatus in which a detection element or the like is housed in a casing and can be carried has been developed and put into practical use (see, for example, Patent Documents 2 and 3).

  By the way, in such a radiographic imaging apparatus, a plurality of radiation detection elements are arranged in a two-dimensional shape (matrix shape) to form a detection unit. At this time, the number of radiation detection elements (that is, the number of pixels) is Usually, the number of pixels is several million to several tens of millions or more. Therefore, if the image data read from each radiation detection element is transferred to the external device without being compressed, the transfer time becomes longer. Further, in a portable radiographic imaging apparatus with a built-in battery, when the transfer time of image data becomes long, the power consumed at the time of transfer increases, leading to battery consumption.

Therefore, the read image data is usually compressed by a data compression method such as lossless compression (also referred to as lossless compression) or lossy compression (also referred to as lossy compression), and is then transferred to an external device such as a console or server. Transferred.
For example, when a radiographic image captured by a radiographic image capturing apparatus is used as a medical image used for diagnosis or the like, as a data compression method for compressing image data, information that image data has by compression is generally used. It is preferable to adopt a lossless compression method in which compression is performed so that the pre-compression image data and the restored image data completely coincide with each other, rather than the lossy compression method in which a part of the image is lost. It has been.

However, even when the reversible compression method is employed, there is a case where sufficient compression is not performed when there is variation in each image data, and the compression processing time, the data transfer time, etc. cannot be sufficiently reduced. .
Further, some radiation detection elements of the radiographic imaging apparatus may output an abnormal detection value from the beginning of manufacture, and this abnormal detection value hinders efficient compression of image data. It was.
Therefore, the position information of the radiation detection element showing an abnormal detection value is stored in advance as a defective pixel map, and at the time of radiographic imaging, the detection value is not adopted for the radiation detection element showing an abnormal detection value, A radiographic imaging apparatus has been developed that employs detection values obtained by interpolation processing from detection values of surrounding radiation detection elements. As a result, the influence of abnormality of the radiation detection element is eliminated, and the dispersion of image data is eliminated (see, for example, Patent Document 4).

JP-A-9-73144 JP 2006-058124 A JP-A-6-342099 JP 2009-172078 A

However, there is a problem that it is difficult to improve the compression rate simply by reversibly compressing image data.
In order to explain this, first, an example of processing for image data and processing for displaying a radiographic image in the radiographic imaging system will be described with reference to the flowchart of FIG.

  In the radiographic imaging system, the radiographic imaging device reads image data from the radiation detection element by a readout circuit (step S101), performs compression processing on the read image data, and creates compressed image data. (Step S102), the compressed image data is transferred to an external device such as a console (Step S103).

  When an external device such as a console receives the compressed image data transferred from the radiographic image capturing device, the external device performs a decompression process on the compressed image data (step S104), and the decompressed image data. An offset correction process is performed (step S105), a gain correction process is performed on the image data after the offset correction (step S106), and a defective pixel correction process is performed on the image data after the gain correction (step S107). Then, a predetermined display process is performed on the image data after the defective pixel correction (step S108), and a radiation image based on the image data is displayed on the display unit (step S109).

  By the way, in the process of performing compression processing on image data to create compressed image data (step S103), a lossless compression processing method such as Huffman coding is used. In Huffman coding, data with higher appearance frequency is assigned a shorter Huffman code, thereby compressing data as a whole.

  However, it is assumed that the distribution of the appearance frequency F of the image data D is, for example, as shown in FIG. In the distribution shown in FIG. 22, since the distribution range of the image data D having a relatively high appearance frequency F is wide, there is a problem that the image data D to which a relatively long Huffman code is assigned increases and the compression rate does not increase so much. End up.

In addition, an external device such as a console is a thinned image obtained by thinning pixels from image data at a predetermined ratio prior to displaying a medical radiographic image (diagnostic radiographic image) used for diagnosis or the like on a display unit. May be configured to be displayed for preview.
In this case, for example, the radiographic image capturing apparatus 1 transfers all the image data for one image or the remaining image data remaining after the thinning process to the console 58 after transferring the image data for the thinned image to the console 58 as compressed image data. 58.

  The inventor of the present application analyzed the compression ratio in detail for the image data for the thinned image and the entire image data or the remaining image data for one image, and as a result, the compression ratio of the image data acquired by the radiographic image capturing apparatus is further increased. We have found a reversible data compression method that can be improved.

  The present invention has been made in view of the above points, and provides a radiographic imaging apparatus and a radiographic imaging system capable of improving the compression rate when compressing image data acquired by radiographic imaging. The purpose is to do.

In order to solve the above-described problem, the radiographic imaging device of the present invention includes:
A plurality of scanning lines and a plurality of signal lines arranged so as to cross each other, and a plurality of radiation detection elements arranged in a two-dimensional manner in each region partitioned by the plurality of scanning lines and the plurality of signal lines A detection unit comprising:
A plurality of readout circuits for reading out charges from the radiation detection elements through the signal lines and outputting the charges as image data for each of the radiation detection elements;
Creating means for creating compressed thinned-out image data and compressed one-image data based on one-image data composed of each image data output from the plurality of readout circuits;
The creating means includes
When creating the compressed thinned image data, thinned image data is created by performing thinning processing in the extending direction of the signal line at a predetermined ratio with respect to the data for one image, and the thinned image data The difference between the image data read from the radiation detection elements adjacent in the extending direction of the scanning line is calculated for each of the image data constituting the difference data, and compression processing is performed on the difference data. To create the compressed thinned image data,
When creating the compressed image data, the difference between the image data read from the radiation detection elements adjacent in the signal line extending direction is calculated for each image data constituting the image data. Differential data is created, and the compressed data is created by performing compression processing on the differential data.

Moreover, the radiographic imaging device of the present invention is
A plurality of scanning lines and a plurality of signal lines arranged so as to cross each other, and a plurality of radiation detection elements arranged in a two-dimensional manner in each region partitioned by the plurality of scanning lines and the plurality of signal lines A detection unit comprising:
A plurality of readout circuits for reading out charges from the radiation detection elements through the signal lines and outputting the charges as image data for each of the radiation detection elements;
Creating means for creating compressed thinned image data and uncompressed image data based on one image data composed of each image data output from the plurality of readout circuits;
The creating means includes
When creating the compressed thinned image data, thinned image data is created by performing thinning processing in the extending direction of the signal line at a predetermined ratio with respect to the data for one image, and the thinned image data The difference between the image data read from the radiation detection elements adjacent in the extending direction of the scanning line is calculated for each of the image data constituting the difference data, and compression processing is performed on the difference data. To create the compressed thinned image data,
When creating the compressed residual image data, image data read from the radiation detection elements adjacent to each other in the signal line extending direction for each image data constituting the residual image data after the thinning process It is characterized in that difference data is created by calculating a difference, and the compressed image data is created by performing compression processing on the difference data.

Moreover, the radiographic imaging system of the present invention is
A radiographic imaging apparatus comprising transfer means for transferring the compressed thinned-out image data created by the creating means and the compressed one-image data to an external device;
When the compressed thinned image data is transferred from the radiation image capturing apparatus, the compressed thinned image data is decompressed to the original difference data, and the original thinned image data is based on the difference data. When the compressed image data is transferred from the radiographic imaging device, the compressed image data is decompressed into the original difference data, and the original data is based on the difference data. And a console for restoring data for one image.

Moreover, the radiographic imaging system of the present invention is
A radiographic imaging apparatus comprising transfer means for transferring the compressed thinned-out image data and the compressed uncompressed image data created by the creating means to an external device;
When the compressed thinned image data is transferred from the radiation image capturing apparatus, the compressed thinned image data is decompressed to the original difference data, and the original thinned image data is based on the difference data. And when the compressed residual image data is transferred from the radiographic imaging device, the compressed residual image data is decompressed to the original difference data, and the original data based on the differential data is extracted. And a console for restoring the remaining image data.

  According to the radiographic imaging apparatus and radiographic imaging system of the system of the present invention, when creating data for one compressed image or data for an uncompressed image, difference data in the extending direction of the signal line, that is, the same When creating difference data of each image data read from a plurality of radiation detection elements connected to the signal line, compressing the difference data, and creating compressed thinned image data, scanning is performed. Create differential data in the line extending direction, that is, differential data of each image data read from a plurality of radiation detection elements connected to the same scanning line, and compress the differential data did. That is, it is configured to switch between taking a difference in the extending direction of the signal line and taking a difference in the extending direction of the scanning line according to the type of compressed image data to be created.

  Therefore, when creating one compressed image data or uncompressed image data, a compression process is performed on the difference data of each image data read by the same readout circuit. It becomes possible to prevent the distribution of differential data from spreading due to the variation in characteristics and reduce the compression ratio, and when creating compressed thinned image data, the radiation detection elements adjacent to each other Since the compression process is performed on the difference data of each image data read out from, the distribution of the difference data spreads depending on the distance between the radiation detection elements to prevent the compression rate from being lowered. Thus, it is possible to accurately improve the compression ratio when compressing difference data of image data acquired by radiographic imaging.

  In addition, the difference data can be compressed at a high compression ratio, so the amount of data to be transferred is reduced and the transfer time is shortened, reducing the power consumption of the entire radiographic imaging apparatus and radiographic imaging system. It becomes possible to make it.

It is a perspective view which shows the radiographic imaging apparatus which concerns on this embodiment. It is sectional drawing which follows the AA line in FIG. It is a top view which shows the structure of the board | substrate of a radiographic imaging apparatus. FIG. 4 is an enlarged view showing a configuration of a radiation detection element, a TFT and the like formed in a small region on the substrate of FIG. 3. It is sectional drawing which follows the XX line in FIG. It is a side view explaining the board | substrate with which COF, a PCB board | substrate, etc. were attached. It is a block diagram showing the equivalent circuit of a radiographic imaging apparatus. It is a block diagram showing the equivalent circuit about 1 pixel which comprises a detection part. It is a figure explaining the state where the image data read from the radiation detection element at the same time by each readout IC is rearranged after being stored in the buffer memory and transmitted to the storage means. (A) is a diagram for explaining data for one image, (B) is a diagram for explaining thinned image data, and (C) is a diagram for explaining remaining image data. It is a figure explaining the case where a difference is taken in a signal line direction. It is a figure explaining the method of the production | generation of the difference data of the image data adjacent to the structure of a register part, and the signal line direction connected to the same signal line in this embodiment. It is a figure explaining the case where a difference is taken in a signal line direction about each image data read from each radiation detection element connected to line L1 of a scanning line. (A)-(C) It is a figure explaining the method of producing the difference data of the image data adjacent to the signal line direction connected to the same signal line using one buffer register. It is a figure explaining the case where a difference is taken in a scanning line direction. It is a figure explaining the method of the production | generation of the difference data of the structure of a register part, and the image data adjacent to the scanning line direction connected to the same scanning line in this embodiment. (A)-(C) It is a figure explaining the method of producing the difference data of the image data adjacent to the scanning line direction connected to the same scanning line using one buffer register. It is a figure which shows the whole structure of the radiographic imaging system which concerns on this embodiment. FIG. 6 is a distribution of difference data obtained when radiation is uniformly applied to a radiographic image capturing apparatus, and is a diagram showing a distribution of difference data created by taking a difference in the scanning line direction for each image data constituting one image data It is. FIG. 6 is a distribution of difference data obtained when radiation is uniformly applied to a radiographic image capturing apparatus, and shows a distribution of difference data created by taking differences in the signal line direction for each image data constituting one image data. It is. It is a flowchart for demonstrating an example of the process regarding image data and the process regarding the display of a radiographic image in a radiographic imaging system. It is a graph which shows an example of distribution of appearance frequency of image data.

  Hereinafter, preferred embodiments of the present invention will be described with reference to the drawings. However, embodiments to which the present invention is applicable are not limited to this, and the present invention is not limited to the illustrated examples.

In the following, a scintillator or the like is provided as a radiographic image capturing device, and the irradiated radiation is converted into electromagnetic waves having other wavelengths such as visible light and irradiated, and converted into image data that is an electrical signal by the radiation detection element. The so-called indirect type radiographic imaging apparatus will be described. However, the present invention can also be applied to a so-called direct type radiographic imaging apparatus that directly detects radiation with a radiation detection element without using a scintillator or the like. it can.
Although the case where the radiographic imaging apparatus is a portable radiographic imaging apparatus will be described, the present invention can also be applied to a radiographic imaging apparatus formed integrally with a support base or the like.

[Radiation imaging equipment]
First, the configuration of the radiographic image capturing apparatus according to the present embodiment will be described.
FIG. 1 is an external perspective view of the radiographic image capturing apparatus according to the present embodiment, and FIG. 2 is a cross-sectional view taken along line AA in FIG.
The radiographic image capturing apparatus 1 according to the present embodiment 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 image capturing. It generates and acquires image data corresponding to the dose.
As shown in FIGS. 1 and 2, the radiographic image capturing apparatus 1 is configured by housing a scintillator 3, a substrate 4, and the like in a housing 2.

The housing 2 is formed of a material such as a carbon plate or plastic that at least the radiation incident surface R transmits radiation.
In addition, in FIG.1 and FIG.2, although the case 2 is what is called a lunch box type | mold formed with the frame board 2A and the back board 2B, it is not limited to this, For example, Also, it is possible to adopt a so-called monocoque type in which the housing 2 is integrally formed in a rectangular tube shape.

As shown in FIG. 1, in the present embodiment, a power switch 36, an indicator 37 composed of an LED, etc., a battery 41 (see FIG. 7 to be described later) are replaced on the side surface of the housing 2. A lid member 38 that can be opened and closed is disposed.
Further, in the present embodiment, an antenna device 39 that is a transfer means for wirelessly transferring image data or the like to an external device such as a console 58 (see FIG. 18 described later) is embedded in the side surface portion of the lid member 38. It is. It is also possible to transfer the image data or the like to an external device in a wired manner. In this case, for example, as a transfer means, a connection terminal or the like for connecting by inserting a cable or the like is used as radiation. Provided on the side surface of the image capturing apparatus 1 or the like.

  As shown in FIG. 2, a base 31 is disposed inside the housing 2 via a lead thin plate (not shown) on the lower side of the substrate 4, and an electronic component 32 and the like are disposed on the base 31. The PCB substrate 33, the buffer member 34, and the like are attached. In the present embodiment, a glass substrate 35 for protecting the substrate 4 and the scintillator 3 on the radiation incident surface R side is disposed.

  The scintillator 3 is bonded to a detection part P (described later) of the substrate 4. In this embodiment, the scintillator 3 is, for example, a phosphor whose main component is converted into an electromagnetic wave having a wavelength of 300 to 800 nm, that is, an electromagnetic wave centered on visible light and output when receiving radiation. .

  In the present embodiment, the substrate 4 is formed of a glass substrate, and as shown in FIG. 3, a plurality of scanning lines 5 and a plurality of signal lines are provided on a surface 4 a of the substrate 4 facing the scintillator 3. 6 are arranged so as to cross each other. A radiation detection element 7 is provided in each small region r defined by the plurality of scanning lines 5 and the plurality of signal lines 6 on the surface 4 a of the substrate 4.

  In this way, the entire region in which a plurality of radiation detection elements 7 arranged in a two-dimensional manner are provided in each small region r partitioned by the scanning line 5 and the signal line 6, that is, shown by a one-dot chain line in FIG. The region is a detection unit P.

In the present embodiment, a photodiode is used as the radiation detection element 7, but, for example, a phototransistor or the like can also be used.
Each radiation detection element 7 is connected to a source electrode 8s of a thin film transistor (hereinafter referred to as “TFT”) 8 as a switch element, as shown in FIG. 4 which is an enlarged view of FIG. 3 or FIG. Yes. The drain electrode 8 d of the TFT 8 is connected to the signal line 6.

The TFT 8 is turned on when the on-voltage is applied to the connected scanning line 5 and the on-voltage is applied to the gate electrode 8g by the scanning drive means 15 (described later), and is stored in the radiation detection element 7. The electric charge is emitted from the radiation detection element 7 to the signal line 6.
The TFT 8 is turned off when an off voltage is applied to the connected scanning line 5 and an off voltage is applied to the gate electrode 8g, and the discharge of the charge from the radiation detecting element 7 to the signal line 6 is stopped. The electric charge generated in the radiation detection element 7 is held and accumulated in the radiation detection element 7.

  Here, the structure of the radiation detection element 7 and the TFT 8 in this embodiment will be briefly described with reference to the cross-sectional view shown in FIG. FIG. 5 is a sectional view taken along line XX in FIG.

  As shown in FIG. 5, a gate electrode 8g of a TFT 8 made of Al, Cr, or the like is formed on the surface 4a of the substrate 4 so as to be integrally laminated with the scanning line 5, and the gate electrode 8g and the surface 4a. The radiation detecting element 7 is disposed above the gate electrode 8g on the gate insulating layer 81 made of silicon nitride (SiNx) or the like laminated on the semiconductor layer 82 made of hydrogenated amorphous silicon (a-Si) or the like. The source electrode 8 s connected to the first electrode 74 and the drain electrode 8 d formed integrally with the signal line 6 are laminated.

  The source electrode 8s and the drain electrode 8d are divided by a first passivation layer 83 made of silicon nitride (SiNx) or the like, and the first passivation layer 83 covers the electrodes 8s and 8d from above. In addition, ohmic contact layers 84a and 84b formed in an n-type by doping hydrogenated amorphous silicon with a group VI element are stacked between the semiconductor layer 82 and the source electrode 8s and the drain electrode 8d, respectively. The TFT 8 is formed as described above.

  In the radiation detection element 7, an auxiliary electrode 72 is formed by laminating Al, Cr or the like on an insulating layer 71 formed integrally with the gate insulating layer 81 on the surface 4 a of the substrate 4. A first electrode 74 made of Al, Cr, Mo or the like is laminated on the auxiliary electrode 72 with an insulating layer 73 formed integrally with the first passivation layer 83 interposed therebetween. The first electrode 74 is connected to the source electrode 8 s of the TFT 8 through the hole H formed in the first passivation layer 83. Note that the auxiliary electrode 72 is not necessarily provided.

  On the first electrode 74, an n layer 75 formed in an n-type by doping a hydrogenated amorphous silicon with a group VI element, an i layer 76 which is a conversion layer formed of hydrogenated amorphous silicon, and a hydrogenated amorphous A p layer 77 formed by doping a group III element into silicon and forming a p-type layer is formed by laminating sequentially from below.

  When the radiation irradiated to the radiographic imaging apparatus 1 enters from the radiation incident surface R of the housing 2 and is converted into an electromagnetic wave such as visible light by the scintillator 3, and the converted electromagnetic wave is irradiated from above in the figure. The electromagnetic waves reach the i layer 76 of the radiation detection element 7, and electron-hole pairs are generated in the i layer 76. In this way, the radiation detection element 7 converts the electromagnetic waves irradiated from the scintillator 3 into electric charges.

  On the p layer 77, a second electrode 78 made of a transparent electrode such as ITO is laminated and formed so that the irradiated electromagnetic wave reaches the i layer 76 and the like. In the present embodiment, the radiation detection element 7 is formed as described above. The order of stacking the p layer 77, the i layer 76, and the n layer 75 may be reversed. In the present embodiment, as the radiation detection element 7, a case where a so-called pin-type radiation detection element formed by sequentially stacking the p layer 77, the i layer 76, and the n layer 75 as described above is described. However, it is not limited to this.

  A bias line 9 for applying a bias voltage to the radiation detection element 7 is connected to the upper surface of the second electrode 78 of the radiation detection element 7 via the second electrode 78. The second electrode 78 and the bias line 9 of the radiation detection element 7, the first electrode 74 extended to the TFT 8 side, the first passivation layer 83 of the TFT 8, that is, the upper surfaces of the radiation detection element 7 and the TFT 8 are The upper side is covered with a second passivation layer 79 made of silicon nitride (SiNx) or the like.

  As shown in FIGS. 3 and 4, in the present embodiment, one bias line 9 is connected to a plurality of radiation detection elements 7 arranged in rows, and each bias line 9 is a signal line. 6 in parallel. Further, as shown in FIG. 3, each bias line 9 is bound to the connection 10 at a position outside the detection portion P of the substrate 4.

  Further, in the present embodiment, the connection lines 10 of the scanning lines 5, the signal lines 6, and the bias lines 9 are respectively connected to input / output terminals (also referred to as pads) 11 provided near the edge of the substrate 4. Yes. As shown in FIG. 6, a COF (Chip On Film) 12 in which a chip such as an IC 12 a is incorporated in each input / output terminal 11 includes an anisotropic conductive adhesive film (Anisotropic Conductive Film) or an anisotropic conductive paste ( It is connected via an anisotropic conductive adhesive material 13 such as Anisotropic Conductive Paste).

  The COF 12 is routed to the back surface 4b side of the substrate 4 and connected to the PCB substrate 33 on the back surface 4b side. Thus, the board | substrate 4 part of the radiographic imaging apparatus 1 is formed. In FIG. 6, illustration of the electronic component 32 and the like is omitted.

Here, the circuit configuration of the radiation image capturing apparatus 1 will be described.
FIG. 7 is a block diagram illustrating an equivalent circuit of the radiographic image capturing apparatus 1 according to the present embodiment, and FIG. 8 is a block diagram illustrating an equivalent circuit for one pixel constituting the detection unit P.

As described above, each radiation detection element 7 of the detection unit P of the substrate 4 has the bias line 9 connected to the second electrode 78, and each bias line 9 is bound to the connection 10 to the bias power supply 14. It is connected. The bias power supply 14 applies a bias voltage to the second electrode 78 of each radiation detection element 7 via the connection 10 and each bias line 9.
The bias power supply 14 is connected to a control means 22 (described later), and the bias voltage applied from the bias power supply 14 to each radiation detection element 7 is controlled by the control means 22.

  In the present embodiment, the current detection means 43 for detecting the amount of current flowing through the connection 10 (bias line 9) is provided in the connection 10 of the bias line 9. As described above, when the radiation imaging apparatus 1 is irradiated with radiation, electron-hole pairs are generated in the i layer 76 (see FIG. 5) of each radiation detection element 7, and this is the bias line 9 or the connection. The current detection means 43 can detect the start and end of radiation irradiation by detecting the increase or decrease of the current flowing through the connection 10. Note that the current detection means 43 is not necessarily provided.

  As shown in FIGS. 7 and 8, in this embodiment, it can be seen that the bias line 9 is connected via the second electrode 78 to the p-layer 77 side (see FIG. 5) of the radiation detection element 7. In addition, the bias power supply 14 supplies a voltage equal to or lower than a voltage applied to the second electrode 78 of the radiation detection element 7 via the bias line 9 as a bias voltage on the first electrode 74 side of the radiation detection element 7 (that is, a so-called reverse bias voltage). Is applied.

  The first electrode 74 of each radiation detection element 7 is connected to the source electrode 8s of the TFT 8 (indicated as S in FIGS. 7 and 8), and the gate electrode 8g of each TFT 8 (FIGS. 7 and 8). Are connected to the lines L1 to Lx of the scanning line 5 extending from the gate driver 15b of the scanning driving means 15 (described later). Further, the drain electrode 8 d (denoted as D in FIGS. 7 and 8) of each TFT 8 is connected to each signal line 6.

  In the present embodiment, the scanning drive unit 15 includes a power supply circuit 15a that supplies an on voltage and an off voltage to the gate driver 15b, and a voltage applied to each line L1 to Lx of the scanning line 5 between the on voltage and the off voltage. A gate driver 15b that switches between the on state and the off state of each TFT 8 is provided. In the present embodiment, the gate driver 15b is formed with a plurality of the above-described ICs 12a arranged side by side.

  Each signal line 6 is connected to each readout circuit 17 formed in the readout IC 16. Note that the readout IC 16 is provided with one readout circuit 17 for each signal line 6.

  The read circuit 17 mainly includes a read circuit 17 including an amplifier circuit 18 and a correlated double sampling circuit 19, an analog multiplexer 21, and an A / D converter 20. 7 and 8, the correlated double sampling circuit 19 is represented as CDS. In FIG. 8, the analog multiplexer 21 is omitted.

  In the present embodiment, the amplifier circuit 18 includes a charge amplifier circuit, and includes an operational amplifier 18a, a capacitor 18b and a charge reset switch 18c connected in parallel to the operational amplifier 18a. In addition, a power supply unit 18 d for supplying power to the amplifier circuit 18 is connected to the amplifier circuit 18.

The signal line 6 is connected to the inverting input terminal on the input side of the operational amplifier 18 a of the amplifier circuit 18, and the reference potential V ₀ is applied to the non-inverting input terminal on the input side of the amplifier circuit 18. Yes.
The reference potential V ₀ is set to an appropriate value, and in this embodiment, for example, 0 [V] is applied.

Further, the charge reset switch 18c of the amplifier circuit 18 is connected to a control means 22 (described later), and is configured to be turned on / off by the control means 22.
When the image data is read from each radiation detection element 7, when the charge reset switch 18c is turned off and the TFT 8 of the radiation detection element 7 is turned on (that is, the scanning line 5 is applied to the gate electrode 8g of the TFT 8). When an on-voltage for signal readout is applied via the signal), the electric charge released from the radiation detection element 7 flows into the capacitor 18b and is accumulated, and a voltage value corresponding to the accumulated electric charge is output from the operational amplifier 18a. It is configured to output from the side. In this way, the amplifier circuit 18 outputs a voltage value according to the amount of charge output from each radiation detection element 7 and converts the charge voltage.

  Further, when the charge reset switch 18c is turned on, the input side and the output side of the amplifier circuit 18 are short-circuited, and the charge accumulated in the capacitor 18b is discharged, so that the amplifier circuit 18 is reset. It is configured. Note that the amplifier circuit 18 may be configured to output a current in accordance with the charge output from the radiation detection element 7.

  At the time of reading the image data from each radiation detection element 7, the charge is read from each radiation detection element 7, and the voltage value that is output after being subjected to charge-voltage conversion by the amplifier circuit 18 is sampled by the correlated double sampling circuit 19. It is processed and output downstream as image data. The image data of each radiation detection element 7 output from the correlated double sampling circuit 19 is transmitted to the analog multiplexer 21 (see FIG. 7), and is sequentially transmitted from the analog multiplexer 21 to the A / D converter 20. Then, the A / D converter 20 sequentially converts the image data into digital values, outputs them to the storage means 40, and sequentially stores them.

  In the present embodiment, when the image data is read from each radiation detection element 7, the lines L1 to Lx of the scanning line 5 to which the ON voltage is applied are sequentially switched, and the above-described respective A process for reading image data from the radiation detection element 7 is performed.

Here, in the present embodiment, the 128 signal lines 6 are processed by one readout IC 16.
That is, one read IC 16 mainly includes 128 read circuits 17 (that is, an amplifier circuit 18 and a correlated double sampling circuit 19) corresponding to each signal line 6, one analog multiplexer 21, and 1 The two A / D converters 20 are formed.

When the number of signal lines 6 is 2048, for example, 2048/128 = 16 readout ICs 16 are arranged in parallel to form a readout unit.
Hereinafter, the number of readout circuits 17 formed in one readout IC 16, that is, the number of signal lines 6 connected to one readout IC 16 is 128, and the total number of signal lines 6 is 2048. However, it goes without saying that the present invention is not limited to this case.

  As shown in FIG. 9, when an on-voltage is applied to the line L <b> 1 of the scanning line 5, for example, when the image data is read out, the radiation detection elements 7 connected to the line L <b> 1 of the scanning line 5 simultaneously. Image data is read out and sent to each reading IC 16 in parallel.

  Then, charge voltage conversion and the like are performed in each readout circuit 17 in each readout IC 16, and 128 image data transmitted in parallel are sequentially sent to the A / D converter 20 by the analog multiplexer 21 in each readout IC 16. The serially transferred and digitized image data is temporarily stored in the buffer memory 45 from the A / D converter 20.

  That is, the radiation detection element 7 corresponding to the pixel at the pixel position (n, m) is represented as a radiation detection element (n, m), and image data read from the radiation detection element (n, m) is represented by D (n, m). m), each image data of image data D (1, 1), D (1, 129), D (1, 257),..., D (1, 1921) is transmitted from each readout IC 16 first. And stored in the buffer memory 45. Subsequently, the image data D (1,2), D (1,130), D (1,258),..., D (1,1922) are transmitted. Are stored in the buffer memory 45.

  Then, the image data D (1, 1) to D (1, 2048) from the radiation detection elements (1, 1) to (1, 2048) connected to the line L1 of the scanning line 5 are stored in the buffer memory 45. Are stored, the image data are rearranged in the order of image data D (1,1), D (1,2), D (1,3), D (1,4),. 40 are sequentially transmitted and stored.

  In addition, the reading process of each image data D (1,1) to D (1,2048) from each radiation detection element (1,1) to (1,2048) connected to the line L1 of the scanning line 5 is completed. Then, the line of the scanning line 5 to which the ON voltage is applied is subsequently switched to L2. Similarly, the image data D (2,1) to D (2,2048) are transmitted to the buffer memory 45 for each readout IC 16 and rearranged, and then sequentially transmitted to the storage means 40 and stored. The

  The reading process and the storing process in the storage unit 40 are sequentially repeated for each of the lines L1 to Lx of the scanning line 5, and the reading process of the image data from all the radiation detection elements 7 is performed. Has been.

  Note that this image data rearrangement process is usually performed by converting the image data into image data D (1, 1), whatever the external device to which the image data is transferred from the radiation image capturing apparatus 1. Since it can be handled by transferring in the order of D (1,2), D (1,3), D (1,4),..., General-purpose at the stage of storing image data in the storage means 40 The image data is rearranged in the above order and stored.

  Therefore, when the order of transferring the image data from the radiation image capturing apparatus 1 to the external apparatus can be determined in advance, the image data can be rearranged according to the determination.

  Further, image data D (1, 1), D (1, 129),..., D (1, 1921) in advance, for example, in the order in which each image data is output from the radiation image capturing apparatus 1 to the external apparatus. , D (1,2), D (1,130),..., D (1,1922),..., The image data output from each readout IC 16 is stored in the buffer memory. It is also possible to send the data directly to the storage means 40 and save them without going through 45.

  Furthermore, when rearranging the image data as described above, the image data is rearranged when each image data is read from the storage means 40, not when each image data is stored in the storage means 40. It is also possible to configure.

  In the present embodiment, each image data (difference) is stored when the image data read from each radiation detection element 7 is temporarily stored in the storage unit 40 as described above and then transferred from the radiation image capturing apparatus 1 to the external apparatus. The case of performing compression processing on the data) will be described. However, each image data read from each radiation detection element 7 is not stored in the storage unit 40 or is separately processed in parallel with the storage in the storage unit 40. The image data (difference data) can be compressed and transferred directly.

The control means 22 is constituted by a computer having a central processing unit (CPU), a read only memory (ROM), a random access memory (RAM), an input / output interface or the like connected to a bus, or a field programmable gate array (FPGA). ing. The control means 22 may be configured with a dedicated control circuit.
And the control means 22 controls operation | movement etc. of each function part of the radiographic imaging apparatus 1.

As shown in FIG. 7 and the like, the control means 22 is connected to a storage means 40 composed of a DRAM (Dynamic RAM) or the like.
In the present embodiment, an antenna device 39 is connected to the control unit 22, and each functional unit such as the detection unit P, the scanning drive unit 15, the readout circuit 17, the storage unit 40, and the bias power source 14 is further connected. A battery 41 for supplying power is connected. A connection terminal 42 for charging the battery 41 by supplying power to the battery 41 from a charging device such as a cradle 55 (see FIG. 18 described later) or the like is attached to the battery 41.

  As described above, the control means 22 controls the bias power supply 14 to set a bias voltage to be applied to each radiation detection element 7 from the bias power supply 14, or the charge reset switch 18 c of the amplification circuit 18 of the readout circuit 17. It is configured to perform various processes such as controlling on / off, transmitting a pulse signal to the correlated double sampling circuit 19 of the readout circuit 17, and controlling on / off of its sample hold function. Yes.

  Further, the control means 22 performs scanning from the scanning driving means 15 to the scanning driving means 15 at the time of reset processing of each radiation detecting element 7 or reading of image data from each radiation detecting element 7 after radiographic imaging. A pulse signal for switching the voltage applied to the gate electrode 8g of each TFT 8 between the on voltage and the off voltage via the line 5 is transmitted.

  In the present embodiment, the control unit 22 is connected to a register unit 44 having at least two buffer registers, and the control unit 22 and the register unit 44 form the creation unit of the present invention.

In the present embodiment, when the control means 22 is configured by an FPGA, a register provided integrally with the FPGA may be used as the register unit 44. When the means 22 is constituted by a computer comprising a CPU or the like, it is also possible to use an existing register as the register unit 44 in the computer.
In the present embodiment, two buffer registers are provided in the register unit 44. However, the present invention is not limited to this. For example, it is possible to provide one buffer register as described later. It is also possible to provide three or more buffer registers.

<Creation of data for one compressed image, compressed thinned image data, and uncompressed image data>
Hereinafter, creation of one compressed image data, compressed thinned-out image data, and uncompressed image data by the control unit 22 as a creating unit will be described.

  In this embodiment, as will be described later, after the compressed one-image data, the compressed thinned-out image data, and the uncompressed image data are created, the data is not stored in the storage unit 40 as it is and is transmitted from the antenna device 39 by a wireless method. Although the case of transferring to an external device will be described, it is also possible to configure so that the created compressed image data, compressed thinned image data, and uncompressed image data are stored in the storage means 40 of the radiation image capturing apparatus 1. It is.

  Here, the compressed data for one image is composed of all image data for one image as shown in FIG. 10A, that is, in this embodiment, image data D (1, 1) to D ( x, 2048) is compressed image data created when transferring data for one image to an external device.

Further, the compressed thinned image data is the extending direction of the signal line 6 at a predetermined rate (1/4 in this embodiment) with respect to the data for one image as shown in FIG. This is compressed image data created when thinned image data created by performing a thinning process (hereinafter referred to as “signal line direction”) is transferred to an external device.
That is, the compressed thinned image data is a predetermined number of lines (3 in the present embodiment) among the image data output from the radiation detection elements 7 connected to the lines L1 to Lx of the scanning line 5. Created when transferring thinned image data created by extracting each image data lined up in the extending direction of the scanning line 5 (hereinafter referred to as “scanning line direction”) every other line) to the external device. Compressed image data.

  Further, the remaining compressed image data is compression generated when the remaining image data remaining after the thinning out of one image data as shown in FIG. 10C is transferred to the external device. It is data.

<Difference>
First, the difference between image data will be described.
In this embodiment, the image data is finely divided into gradations comparable to an analog image using a conventional silver salt film, so that the dynamic range of data values that each image data can take is extremely high. Become bigger.
For example, when the image data has 2 ¹⁶ (= 65536) gradations, the image data can take each data value between 0 and 65535. Therefore, for example, when a method such as Huffman coding is used as a compression method for image data as described later, there is a possibility that the compression rate of the image data does not necessarily become a good value.

On the other hand, in the case of a radiographic image, it is known that when the difference between image data read from the radiation detection elements 7 adjacent to each other is calculated, the distribution of the difference is a relatively narrow range.
Therefore, in the present embodiment, the difference between the image data read from the radiation detection elements 7 adjacent to each other is calculated to create difference data, and compression processing is performed on the difference data.

In this embodiment, as described later, when creating one compressed image data or uncompressed image data, a difference is taken in the signal line direction, and when creating compressed thinned image data, the scanning line direction is used. It is comprised so that a difference may be taken.
That is, it is configured to switch between taking a difference in the signal line direction and taking a difference in the scanning line direction depending on the type of compressed image data to be created.

<Creation of difference data when creating compressed image data>
Next, creation of difference data when creating compressed image data will be described.
First, as shown in FIG. 11, the control unit 22 first stores image data D (n, 1), D (n, 2), D (n, 3), D of each line Ln of the scanning line 5 from the storage unit 40. (N, 4), ... are read out. Next, each image data in the signal line direction, that is, each image data D (1, m), D (2, m), D (3,3) read from each radiation detection element 7 connected to the same signal line 6. For m), D (4, m),..., the difference between adjacent image data is calculated to create difference data, and the difference data is compressed. Note that the vertical arrows in FIG. 11 indicate the direction in which the difference is made when creating compressed image data, that is, the signal line direction in this case.

  Here, in the present embodiment, the register unit 44 is provided with at least two buffer registers 44 a and 44 b as shown in FIG. 12, and each of the compressed differential data is transmitted via the antenna device 39. A buffer memory 44c for temporarily storing the data before transferring it to the external device.

  The control means 22 reads from the radiation detection elements 7 connected to the lines Ln and Ln + 1 of the adjacent scanning lines 5 from the storage means 40 when creating the difference data at the time of creating the compressed image data. Each image data D (n, 1), D (n, 2), D (n, 3), D (n, 4),..., D (n + 1, 1), D ( n + 1, 2), D (n + 1, 3), D (n + 1, 4),... are read out and temporarily stored in the buffer registers 44a and 44b, respectively.

  Thereafter, the difference between the image data at the same address in the buffer registers 44a and 44b is calculated, and the difference data ΔD (n + 1,1), ΔD (n + 1,2), ΔD (n + 1,3), ΔD (n + 1,4) Are created so as to create difference data between the image data read from the radiation detection elements 7 adjacent to each other in the signal line direction connected to the same signal line 6.

  At this time, if the image data arranged in the scanning line direction for two adjacent lines is read from the storage unit 40 every time in order to create the difference data, the reading control becomes troublesome.

  For this reason, in the present embodiment, the control unit 22 obtains difference data between the image data arranged in the scanning line direction read from the radiation detecting elements 7 connected to the lines Ln and Ln + 1 of the adjacent scanning line 5. When created, the image data D (n + 1,1), D (n + 1,2), D (n + 1,3), D (n + 1,4),... Are moved from the buffer register 44b to the buffer register 44a, and become empty. Each image data D (n + 2, 1), D (n + 2, 2), D (n + 2, 3), D (n + 2, 4) arranged in the scanning line direction of the line Ln + 2 of the scanning line 5 next adjacent to the buffer register 44b. , ... accumulate.

When the difference data ΔD (n + 2, 1), ΔD (n + 2, 2), ΔD (n + 2, 3), ΔD (n + 2, 4),... Are created, the image data D (n + 2, 1), D (n + 2) are created. , 2), D (n + 2, 3), D (n + 2, 4),... Are transferred from the buffer register 44b to the buffer register 44a, and the image data D (n + 3, 1), D (n + 3, 2) are transferred to the buffer register 44b. , D (n + 3, 3), D (n + 3,4),.
In this way, the process of calculating the difference between the image data at the same address in the buffer registers 44a and 44b while transferring each image data from the buffer register 44b to the buffer register 44a is repeated to sequentially create the difference data. It is configured.

  When configured as described above, the image data D (1,1), D (1,2), arranged in the scanning line direction read from each radiation detecting element 7 connected to the line L1 of the scanning line 5, Difference data ΔD (1,1), ΔD (1,2), ΔD (1,3), ΔD (1,4),... Of D (1,3), D (1,4),. The data used as the standard for this is needed. Therefore, in this embodiment, preset reference data Dc (0, m), specifically, reference data Dc (0,1), Dc (0,2), Dc (0,3), Dc ( 0, 4),... Are stored in advance in a memory such as a ROM provided in the control means 22.

  When the control means 22 creates each difference data ΔD (1,1), ΔD (1,2), ΔD (1,3), ΔD (1,4),... As described above, the reference data Dc (0,1), Dc (0,2), Dc (0,3), Dc (0,4),... Read from the memory are accumulated in the buffer register 44a and stored in the storage means 40. Each image data D (1,1), D (1,2), D (1,3) arranged in the scanning line direction read from each radiation detecting element 7 connected to the line L1 of the read scanning line 5 , D (1,4),... Are accumulated in the buffer register 44b, the difference is calculated, and the difference data ΔD (1,1), ΔD (1,2), ΔD (1,3), ΔD (1 , 4),... Are created.

  At that time, the reference data Dc (0, 1), Dc (0, 2), Dc (0, 3), Dc (0, 4),... Can be set to the same value. Also, different values can be set, and are set as appropriate in advance.

  Even when only one buffer register 44a is provided in the register unit 44, the difference data can be generated by calculating the difference between the image data adjacent in the signal line direction similar to the above. It is.

  First, as shown in FIGS. 14 (A), 14 (B), and 14 (C), the control means 22 starts from each radiation detection element 7 connected to each line Ln, Ln + 1 of the adjacent scanning line 5. Among the read image data arranged in the scanning line direction, the image data D (n, 1), D (n, 2), D (n, 3) arranged in the scanning line direction of the line Ln of the scanning line 5. , D (n, 4),... Are stored in the buffer register 44a.

  In this state, the control means 22 makes the image data D (n + 1, 1), D (n + 1, 2), D (n + 1, 3), D (n + 1) arranged in the scanning line direction of the line Ln + 1 of the adjacent scanning line 5. , 4),... Are sequentially read from the storage means 40, and the corresponding image data D (n, 1), D (n, 2), D (n, 3), D (n, 4),. Are stored in the buffer register 44a while being sequentially replaced. At this time, the difference data between corresponding image data is created and replaced.

  With this configuration, even when only one buffer register 44a is provided, the image data read from the adjacent radiation detection elements 7 connected to the same signal line 6 is similar to the above. Difference data can be created.

  The image data D (n + 1, 1), D (n + 1, 2), D (n + 1, 3), D (n + 1, 4) accumulated in the buffer register 44a while the difference data is created and replaced in this way. ),..., But this time, each image data D (n + 2, 1), D (n + 2, 2), D (n + 2, 3), D (n + 2, 4), sequentially read out from the storage means 40. ... are replaced while differential data is created in sequence. Therefore, even when only one buffer register 44a is provided, it is possible to easily perform the process of creating each difference data continuously.

<Creation of difference data when creating compressed thinned image data>
Next, creation of difference data when creating compressed thinned image data will be described.
When creating the compressed thinned image data, unlike the case of creating the data for one compressed image described above, the difference data is created by calculating the difference between the image data adjacent in the scanning line direction.

  Specifically, as shown in FIG. 15, the control unit 22 firstly stores each line Lb of the scanning line 5 from the storage unit 40 (b = 4a + 1 in this embodiment, where a = 0, 1, 2,. 3,..., Image data D (b, 1), D (b, 2), D (b, 3), D (b, 4),. Next, each image data in the scanning line direction, that is, each image data D (b, 1), D (b, 2), D (b, B) read from each radiation detecting element 7 connected to the same scanning line 5 3) For D (b, 4),..., The difference between adjacent image data is calculated to create difference data, and the difference data is compressed. Note that the horizontal arrows in FIG. 15 indicate the direction in which the difference is made when creating the compressed thinned image data, that is, the scanning line direction in this case.

  As described above, in the present embodiment, the register unit 44 is provided with at least two buffer registers 44a and 44b, as shown in FIG. A buffer memory 44c is provided for temporarily storing the data before transferring the data to the external device via the.

When creating the difference data when creating the compressed thinned image data, the control unit 22 first temporarily stores preset reference data Dc (b, 0) at the head of the buffer register 44a.
Thereafter, the image data D (b, 1), D (b, 2), D arranged in the scanning line direction read from the radiation detecting elements 7 connected to the line Lb of the scanning line 5 from the storage unit 40. (B, 3), D (b, 4),... Are read and temporarily stored in the buffer registers 44a and 44b, respectively.

At this time, the image data D (b, 1) is stored immediately after the reference data Dc (b, 0) stored in the buffer register 44a and at the head of the buffer register 44b.
Next, the image data D (b, 2) is stored immediately after the image data D (b, 1) stored in the buffer register 44a, and the image data D (b, 1) stored in the buffer register 44b is stored. ) Immediately after.
Next, the image data D (b, 3) is stored immediately after the image data D (b, 2) stored in the buffer register 44a, and the image data D (b, 2) stored in the buffer register 44b is stored. ) Immediately after.
Similarly, the image data D (b, 4) to D (b, 2047) are stored in the buffer registers 44a and 44b.
Then, the last image data D (b, 2048) of the image data arranged in the scanning line direction read from each radiation detecting element 7 connected to the line Lb of the scanning line 5 is accumulated in the buffer register 44b. It is stored immediately after the image data D (b, 2047). Note that the image data D (b, 2048) may or may not be stored in the buffer register 44a.

  Thereafter, the difference between the image data of the same address in the buffer registers 44a and 44b is calculated, and the difference data ΔD (b, 1), ΔD (b, 2), ΔD (b, 3), ΔD (b, 4) Are created so as to create difference data between the image data read from the radiation detection elements 7 adjacent to each other in the scanning line direction connected to the same scanning line 5.

In this embodiment, reference data Dc (b, 0) set in advance, specifically, reference data Dc (1, 0), Dc (5, 0), Dc (9, 0), Dc (13, 0),... Are stored in advance in a memory such as a ROM provided in the control means 22.
At this time, each value of the reference data Dc (1, 0), Dc (5, 0), Dc (9, 0), Dc (13, 0),... Can be set to the same value. Also, different values can be set, and are set as appropriate in advance.

  Even when only one buffer register 44a is provided in the register unit 44, it is possible to create a difference data by calculating a difference between adjacent image data in the scanning line direction similar to the above. It is.

First, as shown in FIG. 17A, the control means 22 accumulates the reference data Dc (b, 0) at the head of the buffer register 44a.
In this state, the control means 22 reads the image data D (b, 1) of the image data arranged in the scanning line direction of the line Lb of the scanning line 5 from the storage means 40 and puts it at the head of the buffer register 44a. After the difference data with the accumulated reference data Dc (b, 0) is created, the difference data is replaced with the reference data Dc (b, 0) and accumulated in the buffer register 44a.

  Next, as shown in FIG. 17B, the control means 22 reads out the image data D (b, 2) of the image data arranged in the scanning line direction of the line Lb of the scanning line 5 from the storage means 40. Then, after creating difference data with the image data D (b, 1) stored at the head of the buffer register 44a, the difference data is replaced with the image data D (b, 1) and stored in the buffer register 44a.

Next, as shown in FIG. 17C, the control means 22 reads out the image data D (b, 3) of the image data arranged in the scanning line direction of the line Lb of the scanning line 5 from the storage means 40. Thus, after creating difference data with the image data D (b, 2) stored at the head of the buffer register 44a, the difference data is replaced with the image data D (b, 2) and stored in the buffer register 44a.
In the same manner, difference data is created for image data D (b, 4) to D (b, 2047) and then stored in the buffer register 44a. Note that difference data is created for the last image data D (b, 2048) of the image data arranged in the scanning line direction read from the radiation detecting elements 7 connected to the line Lb of the scanning line 5. After that, it may be accumulated in the buffer register 44a or may not be accumulated.

  With this configuration, even when only one buffer register 44a is provided, the image data read from the adjacent radiation detection elements 7 connected to the same scanning line 5 is similar to the above. Difference data can be created.

<Creation of difference data when creating data for the remaining compressed image>
Next, creation of difference data at the time of creation of data for remaining compressed images will be described.
At the time of creating the data for the remaining compressed image, the difference between the image data adjacent in the signal line direction is calculated to create the difference data, which is the same as the case of creating the data for one compressed image described above. The point that the data for the remaining image after the thinning process is used in the image data is different from the case of creating the compressed data for one image. Therefore, only a different part will be described by taking as an example a case where two buffer registers 44a and 44b are provided.

Specifically, when creating the difference data at the time of creating the remaining compressed image data, the control unit 22 firstly stores each line of the scanning line 5 adjacent to the line Lb of the scanning line 5 from the storage unit 40. Each image data D (b-1, 1), D (b-1, 2), D (b-1) arranged in the scanning line direction read from each radiation detecting element 7 connected to Lb-1, Lb + 1. , 3), D (b-1, 4),..., D (b + 1, 1), D (b + 1, 2), D (b + 1, 3), D (b + 1, 4),. 44a and 44b are temporarily stored.
However, when b = 1, the image data D (b-1, 1) D (b-1, 2), D (b-1, 3), D (b-1, 4),. Data Dc (0, 1), Dc (0, 2), Dc (0, 3), Dc (0, 4),... Are accumulated in the buffer register 44a.

  Thereafter, the difference between the image data of the same address in the buffer registers 44a and 44b is calculated, and the difference data ΔD (b + 1, 1), ΔD (b + 1, 2), ΔD (b + 1, 3), ΔD (b + 1, 4), Create….

  Next, the control means 22 reads from the storage means 40 each image data D (b + 1, b) aligned in the scanning line direction read from each radiation detecting element 7 connected to each line Lb + 1, Lb + 2 of the scanning line 5 adjacent to each other. 1), D (b + 1, 2), D (b + 1, 3), D (b + 1, 4), ..., D (b + 2, 1), D (b + 2, 2), D (b + 2, 3), D (b + 2 , 4),... Are read out and temporarily stored in the buffer registers 44a and 44b, respectively.

  Thereafter, the difference between the image data at the same address in the buffer registers 44a and 44b is calculated, and the difference data ΔD (b + 2, 1), ΔD (b + 2, 2), ΔD (b + 2, 3), ΔD (b + 2, 4), Create….

  Next, the control unit 22 reads each image data D (b + 2, 2) arranged in the scanning line direction read from each radiation detecting element 7 connected to each line Lb + 2, Lb + 3 of the scanning line 5 adjacent to each other from the storage unit 40. 1), D (b + 2, 2), D (b + 2, 3), D (b + 2, 4), ..., D (b + 3, 1), D (b + 3, 2), D (b + 3, 3), D (b + 3 , 4),... Are read out and temporarily stored in the buffer registers 44a and 44b, respectively.

Thereafter, the difference between the image data at the same address in the buffer registers 44a and 44b is calculated, and the difference data ΔD (b + 3, 1), ΔD (b + 3, 2), ΔD (b + 3, 3), ΔD (b + 3, 4), Create….
In this way, difference data that is the basis of the remaining compressed image data is created.

<Compression processing>
Next, compression processing for the created difference data will be described.
In the present embodiment, as described above, the generated difference data is configured to be compressed.

  Here, when using the radiographic image image | photographed with the radiographic imaging apparatus 1 as a medical image used for a diagnosis etc., as a compression processing method with respect to differential data, the differential data before compression and the differential data after decompression | restoration It is preferable to employ a reversible compression method in which compression is performed so that and completely match.

In the present embodiment, the Huffman coding method is adopted as the lossless compression method.
In this embodiment, the Huffman encoding method is adopted as the compression processing method for the difference data, but the compression processing method for the difference data is not necessarily limited to the Huffman encoding method. It is also possible to perform a compression process on the difference data using a lossless compression method or a lossy compression method.

  In the present embodiment, in order to perform the compression process on the difference data by the Huffman encoding method, a table of Huffman codes created in advance for the compression process is stored in a memory such as a ROM provided in the control unit 22 in advance. The control means 22 constituting the creation means is configured to perform Huffman coding of the difference data with reference to this table during the compression process.

  In the present embodiment, the control means 22 is configured to refer to the Huffman code table every time difference data is created as described above and to assign a corresponding Huffman code to the difference data. That is, each Huffman code corresponds to each compressed difference data, and each Huffman code constitutes one compressed image data, compressed thinned image data, and uncompressed image data. In data compression by Huffman coding, as is well known, shorter Huffman codes are assigned to data with higher appearance frequency.

  Then, the control means 22 temporarily stores each Huffman code assigned to each difference data in the buffer memory 44c (see FIG. 12 and the like), and compresses one image data, compressed thinned image data, and uncompressed image data. As described above, the data is sequentially transferred to the external device via the antenna device 39.

  In this case, the external device to which the difference data is transferred from the radiographic image capturing apparatus 1 also includes the same Huffman code table, and the external device transfers the difference data with reference to the table during the decompression process. It is configured to decompress the compressed difference data that has been received.

  The Huffman code table may be configured to include only one type of table, but may be configured to include a plurality of types of tables, and the control unit 22 may select and refer to the table. It is also possible to configure.

  For example, when compression processing is performed on difference data between image data read from radiation detection elements 7 adjacent to each other in the signal line direction, that is, difference data that is a source of compressed image data or uncompressed image data. And the case where the compression processing is performed on the difference data between the image data read from the radiation detection elements 7 adjacent in the scanning line direction, that is, the difference data that is the basis of the compressed thinned image data, The table may or may not be changed.

In addition, for example, when the radiographic imaging device 1 is used as a radiographic imaging device for medical use as described above, the imaging region (chest, skull, lumbar spine, etc.) of the patient's body, which is the subject, and the imaging direction (front, In many cases, the imaging conditions such as the dose of radiation and the irradiation time can be changed depending on the side surface.
Therefore, a plurality of types of Huffman code tables for compression processing are prepared in advance for each imaging condition including the imaging part and imaging direction of the patient's body, which is the subject, and the control means 22 responds to the set imaging condition. If the table is selected, and the Huffman encoding of the difference data is performed with reference to the selected table to compress the difference data, the compression rate of the difference data is further improved in accordance with the shooting conditions. It becomes possible.

  Note that, when taking a medical radiographic image using the radiographic imaging device 1, imaging order information for specifying the imaging region or imaging direction of the patient's body, which is the subject, is often created in advance. The imaging order information and imaging condition information including the imaging region and imaging direction are transferred from the external device to the radiographic imaging device 1, or an operator such as a radiographer sends the imaging order information and imaging to the radiographic imaging device 1. An imaging condition is set for the radiation image capturing apparatus 1 by inputting condition information.

  In addition, the radiographic imaging apparatus 1 and the external apparatus are previously associated with the radiographic imaging apparatus 1 and the external apparatus in advance, and the radiographic imaging apparatus 1 and the external apparatus are associated with the radiographic imaging apparatus 1 and the external apparatus in advance. However, it is possible to specify a table to be used from the imaging region and imaging direction in the imaging order information and to use a common table. In addition, when transferring the Huffman code as the compressed difference data from the radiation imaging apparatus 1 to the external device, the information on the number of the used table is transferred together and designated by the external device with the number information or the like. It is also possible to configure to decompress using a table.

  Further, every time a radiographic image is captured, a control table 22 is transmitted from the external device to the radiographic image capturing device 1 to store the Huffman code table suitable for the radiographic image capturing conditions and store or rewrite the table. It is also possible to perform a compression process by referring to the Huffman code table and performing Huffman encoding of the difference data.

[Radiation imaging system]
Next, the radiographic imaging apparatus 1 according to the present embodiment has received compressed one-image data, compressed thinned-out image data, and uncompressed image data that are composed of compressed difference data (ie, Huffman code). Data restoration on the external device side will be described.
Hereinafter, first, the configuration of the radiographic image capturing system 50 according to the present embodiment will be described.

FIG. 18 is a diagram showing an overall configuration of a radiographic image capturing system 50 according to the present embodiment.
The radiographic image capturing system 50 is a system that assumes radiographic image capturing performed in, for example, a hospital or a clinic, and can be employed as a system that captures a medical diagnostic image as a radiographic image, but is not necessarily limited thereto. Not.

  As shown in FIG. 18, the radiographic image capturing system 50 includes a radiographing room R1 that irradiates radiation and captures a subject that is a part of the patient (a patient's radiographing target site), and a radiographer adjacent to the radiographic room R1. Are arranged in the front chamber R2 for performing various operations such as control of radiation irradiated to the subject by the operator, and the outside thereof.

  In the radiographing room R1, for example, a Bucky device 51 that can be loaded with the radiographic imaging device 1, and a radiation generation device 52 that includes a radiation source (not shown) including an X-ray tube that generates radiation to irradiate the subject. A radio station 53 is provided, and a base station 54 is provided that relays these communications when the radiographic imaging device 1 communicates with an external device such as the console 58.

In FIG. 18, when the portable radiographic imaging device 1 is used in a state where it is loaded in the cassette holding part 51a of the bucky device 51, or when it is used in a single state where it is not loaded in the bucky device 51, specifically, The case where the patient's hand or the like as the subject is placed on the radiation incident surface R and used on the radiation incident surface R is shown. The image capturing device 1 may be formed integrally with the bucky device 51, a support base or the like.
Here, when the portable radiographic image capturing apparatus 1 is used in a state where it is not loaded in the bucky device 51, the portable radiographic image capturing device 1 is disposed on the upper surface side of the bucky device 51B for lying position photographing and is an object on the radiation incident surface R. In addition to placing and using the patient's hand, for example, the patient's hand or the like as a subject is placed on the radiation incident surface R by placing it on the upper surface side of a bed or the like provided in the imaging room R1. Alternatively, for example, the patient can be used by being inserted between a patient's waist or legs lying on the bed and the bed.

In FIG. 18, the radiographic image capturing apparatus 1 and the base station 54 are wirelessly connected, and communication between the radiographic image capturing apparatus 1 and the external device can be performed wirelessly via the base station 54. The radiographic image capturing apparatus 1 and the base station 54 are wired by a LAN (Local Area Network) cable or the like, and communication between the radiographic image capturing apparatus 1 and an external device is performed. It is also possible to configure so that it can be performed in a wired manner via the base station 54.
In FIG. 18, the Bucky device 51 and the base station 54 are connected by wire, and the communication between the radiographic imaging device 1 loaded in the Bucky device 51 and the external device is wired via the base station 54. However, the present invention is not limited to this, and the bucky device 51 and the base station 54 may not be connected by wire.

Further, FIG. 18 shows a case in which one of the standing-up shooting bucky device 51A and the standing-up shooting bucky device 51B is provided as the bucky device 51 in the shooting room R1. The number and type of the bucky devices 51 provided in the photographing room R1 are not particularly limited.
Further, FIG. 18 shows a case where one radiation generating device 52A associated with the bucky device 51 and one portable radiation generating device 52B are provided as the radiation generating device 52 in the imaging room R1. However, the number and type of radiation generators 52 provided in the imaging room R1 are not particularly limited.

  As shown in FIG. 18, in the present embodiment, when the radiographic image capturing apparatus 1 is inserted into the radiographing room R1, a cassette ID for identifying the radiographic image capturing apparatus 1 from the radiographic image capturing apparatus 1 is shown. And a cradle 55 for notifying an external device such as a console 58 via the base station 54. Note that, as described above, the cradle 55 may be configured to charge the radiographic image capturing apparatus 1 or the like.

In the radiographing room R1, a radiation generating device 52 that irradiates the radiographic imaging device 1 with radiation is provided.
In the present embodiment, an operation console 57 of the radiation generating device 52 is provided in the front room R2 adjacent to the imaging room R1, and an operator such as a radiation technician is placed on the operation console 57 by the radiation generating device. An operation switch 56 is provided to be operated when instructing the start of radiation irradiation to 52.

  In addition, the radiation generating device 52 adjusts the radiation irradiation direction so that the radiation image capturing device 1 is appropriately irradiated with radiation by the operator such as a radiologist operating the console 57 or manually. The diaphragm may be adjusted so that the radiation is irradiated within a predetermined region of the radiographic image capturing apparatus 1, or the radiation source may be adjusted so that the radiation having the appropriate dose and the appropriate radiation quality is irradiated. It is configured to be able to.

[console]
As shown in FIG. 18, the console 58 includes a display unit 58a made up of a CRT (Cathode Ray Tube), LCD (Liquid Crystal Display), etc., a control unit 58b for controlling the operation of each functional unit of the console 58, an HDD, and the like. A storage unit 59 (Hard Disk Drive) or the like, and a communication unit (not shown) for communicating with another device such as the radiation imaging apparatus 1 connected to the base station 54 via a LAN cable or the like, The computer includes an input unit (not shown) including a keyboard and a mouse.

18 shows a case where the console 58 is provided outside the photographing room R1 and the front room R2, the console 58 may be provided in the front room R2, for example.
18 shows the case where the storage means 59 is connected to the console 58, the storage means 59 may be built in the console 58.

  The control unit 58b of the console 58 includes a CPU, a ROM, a RAM, and the like. A predetermined program is stored in the ROM, and the CPU reads out a necessary program, expands it in the work area of the RAM, executes various processes according to the program, and controls the operation and the like of each functional unit of the console 58. It is configured as follows.

<Restoration of one image data, thinned image data, and remaining image data>
Hereinafter, restoration of data for one image, thinned image data, and remaining image data in the console 58 will be described.

  The console 58 (specifically, the control unit 58b of the console 58) configures compressed image data, compressed thinned image data, and uncompressed image data from the radiographic image capturing apparatus 1 via the base station 54. When each Huffman code, that is, each compressed difference data is transferred, it is temporarily stored in the storage means 59, and then the data for one image, the thinned image data, and the remaining image data are restored based on them. It is configured as follows.

<Restoring one image data>
First, restoration of data for one image will be described by taking as an example a case where the console 58 is provided with a Huffman code table common to the radiographic image capturing apparatus 1 in advance.
First, the console 58 reads a Huffman code table stored in advance in a ROM or storage means 59 provided in the control unit 58b, refers to the read Huffman code table, and reads each Huffman code table from the radiographic imaging apparatus 1. The Huffman code, specifically, each Huffman code constituting the compressed image data is decompressed to the original difference data. Then, based on the decompressed original difference data, the original one image data, specifically, each image data constituting one image data is restored.

  In this case, the reference data Dc (0, m) described above also on the console 58 side, specifically, the reference data Dc (0, 1), Dc (0, 2), Dc (0, 3), Dc (0, 4). ),... Are stored in advance in a ROM or storage means 59 provided in the control unit 58b, and the console 58 first stores the reference data Dc (0,1), Dc (0,2), Dc (0, 3), Dc (0, 4),... Are read.

Then, referring to the Huffman code table, the Huffman code corresponding to each difference data ΔD (1,1), ΔD (1,2), ΔD (1,3), ΔD (1,4),. To restore the original difference data ΔD (1,1), ΔD (1,2), ΔD (1,3), ΔD (1,4),.
Dc (0, m) + ΔD (1, m) → D (1, m) (1)
To restore the original image data D (1,1), D (1,2), D (1,3), D (1,4),... Aligned in the scanning line direction.
After that, the console 58 stores the restored image data D (1,1), D (1,2), D (1,3), D (1,4),.

  Next, the console 58 refers to the Huffman code table and corresponds to each difference data ΔD (2,1), ΔD (2,2), ΔD (2,3), ΔD (2,4),. The Huffman code is decompressed to restore the original difference data ΔD (2,1), ΔD (2,2), ΔD (2,3), ΔD (2,4),.

Then, using the previously restored image data D (1,1), D (1,2), D (1,3), D (1,4),.
D (1, m) + ΔD (2, m) → D (2, m) (2)
To restore the original image data D (2,1), D (2,2), D (2,3), D (2,4),... Aligned in the scanning line direction. Data D (2, 1), D (2, 2), D (2, 3), D (2, 4), ... are stored in the storage means 59.

In this way, the console 58 refers to the Huffman code table, decompresses the Huffman code corresponding to each difference data ΔD (n, m), and restores the original difference data ΔD (n, m). , Using the previously calculated image data D (n-1, m),
D (n−1, m) + ΔD (n, m) → D (n, m) (3)
By calculating the above, all image data D (n, m) are restored in sequence to restore data for one image.

  Then, the console 58 generates a diagnostic radiographic image, which is a medical radiographic image, based on the one-image data restored in this manner, and displays the diagnostic radiographic image on the display unit 58a or transmits it to another device. Or

<Restoration of thinned image data>
Next, restoration of thinned-out image data will be described by taking as an example a case where the console 58 is previously provided with a Huffman code table common to the radiation image capturing apparatus 1.
First, the console 58 reads a Huffman code table stored in advance in a ROM or storage means 59 provided in the control unit 58b, refers to the read Huffman code table, and reads each Huffman code table from the radiographic imaging apparatus 1. The Huffman code, specifically, each Huffman code constituting the compressed thinned image data is decompressed into the original difference data. Then, based on the decompressed original difference data, the original thinned image data, specifically, each image data constituting the thinned image data is restored.

  In this case, the reference data Dc (b, 0) described above also on the console 58 side, specifically, the reference data Dc (1, 0), Dc (5, 0), Dc (9, 0), Dc (13, 0). ,... Are stored in advance in a ROM or storage means 59 provided in the control unit 58b, and the console 58 first reads the reference data Dc (1, 0) of these reference data.

Then, referring to the Huffman code table, the Huffman code corresponding to each difference data ΔD (1,1), ΔD (1,2), ΔD (1,3), ΔD (1,4),. To restore the original difference data ΔD (1,1), ΔD (1,2), ΔD (1,3), ΔD (1,4),.
D (1, m-1) + ΔD (1, m) → D (1, m) (4)
To restore the original image data D (1,1), D (1,2), D (1,3), D (1,4),... Aligned in the scanning line direction. However, when m = 1, the reference data Dc (1, 0) read out as the image data D (1, m−1) is substituted.
After that, the console 58 stores the restored image data D (1,1), D (1,2), D (1,3), D (1,4),.

  Next, the console 58 reads the reference data Dc (5, 0), refers to the Huffman code table, and sets the difference data ΔD (5, 1), ΔD (5, 2), ΔD (5, 3), The Huffman code corresponding to ΔD (5,4),... Is decompressed, and the original difference data ΔD (5,1), ΔD (5,2), ΔD (5,3), ΔD (5,4), Restore ...

Then, using the restored image data D (5,1), D (5,2), D (5,3), D (5,4),.
D (5, m-1) + ΔD (5, m) → D (5, m) (5)
To restore the original image data D (5,1), D (5,2), D (5,3), D (5,4),... Aligned in the scanning line direction. Data D (5, 1), D (5, 2), D (5, 3), D (5, 4), ... are stored in the storage means 59. However, when m = 1, the reference data Dc (5, 0) read as the image data D (5, m−1) is substituted.

In this way, the console 58 refers to the Huffman code table, decompresses the Huffman code corresponding to each difference data ΔD (b, m), and restores the original difference data ΔD (b, m). , Using the previously calculated image data D (b, m−1),
D (b, m-1) + ΔD (b, m) → D (b, m) (6)
By calculating the above, all the image data D (b, m) are restored in sequence, and the thinned image data is restored.

  The console 58 generates a preview image or the like for confirming the positioning of the subject in radiographic imaging based on the thinned image data restored in this way, and displays the preview image on the display unit 58a.

<Restoring the remaining image data>
Next, the restoration of the remaining image data will be described by taking as an example a case where the console 58 includes a Huffman code table common to the radiation image capturing apparatus 1 in advance.
First, the console 58 reads a Huffman code table stored in advance in a ROM or storage means 59 provided in the control unit 58b, refers to the read Huffman code table, and reads each Huffman code table from the radiographic imaging apparatus 1. The Huffman code, specifically, each Huffman code constituting the uncompressed image data is decompressed to the original difference data. Then, based on the decompressed original difference data, the original remaining image data, specifically, each image data constituting the remaining image data is restored.

The console 58 refers to the Huffman code table, and Huffman codes corresponding to the difference data ΔD (b + 1, 1), ΔD (b + 1, 2), ΔD (b + 1, 3), ΔD (b + 1, 4),. To restore the original difference data ΔD (b + 1,1), ΔD (b + 1,2), ΔD (b + 1,3), ΔD (b + 1,4),.
D (b−1, m) + ΔD (b + 1, m) → D (b + 1, m) (7)
To restore the original image data D (b + 1, 1), D (b + 1, 2), D (b + 1, 3), D (b + 1, 4),... Aligned in the scanning line direction.
Thereafter, the console 58 saves the restored image data D (b + 1, 1), D (b + 1, 2), D (b + 1, 3), D (b + 1, 4),.

  However, in the case of b = 1, the reference data Dc (0, m) stored in advance in the ROM or the storage means 59 provided in the control unit 58b as the image data D (b-1, m), specifically, Substitutes the reference data Dc (0,1), Dc (0,2), Dc (0,3), Dc (0,4),.

  Next, the console 58 refers to the Huffman code table and corresponds to each difference data ΔD (b + 2, 1), ΔD (b + 2, 2), ΔD (b + 2, 3), ΔD (b + 2, 4),. The Huffman code is decompressed to restore the original difference data ΔD (b + 2, 1), ΔD (b + 2, 2), ΔD (b + 2, 3), ΔD (b + 2, 4),.

Then, using the previously restored image data D (b + 1, 1), D (b + 1, 2), D (b + 1, 3), D (b + 1, 4),.
D (b + 1, m) + ΔD (b + 2, m) → D (b + 2, m) (8)
To restore the original image data D (b + 2, 1), D (b + 2, 2), D (b + 2, 3), D (b + 2, 4),... Aligned in the scanning line direction. Data D (b + 2, 1), D (b + 2, 2), D (b + 2, 3), D (b + 2, 4),...

  Next, the console 58 refers to the Huffman code table and corresponds to each difference data ΔD (b + 3, 1), ΔD (b + 3, 2), ΔD (b + 3, 3), ΔD (b + 3, 4),. The Huffman code is decompressed to restore the original difference data ΔD (b + 3, 1), ΔD (b + 3, 2), ΔD (b + 3, 3), ΔD (b + 3, 4),.

Then, using the previously restored image data D (b + 2, 1), D (b + 2, 2), D (b + 2, 3), D (b + 2, 4),.
D (b + 2, m) + ΔD (b + 3, m) → D (b + 3, m) (9)
To restore the original image data D (b + 3, 1), D (b + 3, 2), D (b + 3, 3), D (b + 3, 4),... Aligned in the scanning line direction. Data D (b + 3, 1), D (b + 3, 2), D (b + 3, 3), D (b + 3, 4),.
In this way, the console 58 is configured to sequentially restore all the image data D (b + 1, m), D (b + 2, m), D (b + 3, m) and restore the remaining image data. ing.

  The console 58 then combines the remaining image data restored in this way with the thinned image data restored as described above to create synthesized data. Based on this synthesized data, a diagnostic radiographic image, which is a medical radiographic image, is generated and displayed on the display unit 58a or transmitted to another device.

  As described above, in the case where the radiographic imaging apparatus 1 and the console 58 are provided with a plurality of types of Huffman code tables, information on the table numbers used for the console 58 is transferred from the radiographic imaging apparatus 1. If configured to do so, the console 58 reads the table specified by the transferred number information or the like from the ROM or the storage means 59 and performs decompression processing and restoration processing using the table. Configured as follows.

  In the radiographic image capturing system 50 as described above, the above-described imaging order information for specifying the imaging region and imaging direction of the patient's body, which is the subject, is often created on the console 58 before imaging. Therefore, when imaging is performed based on the imaging order information, the radiographic imaging apparatus 1 side specifies imaging conditions including an imaging region and an imaging direction based on the imaging order information, and a Huffman code corresponding thereto Therefore, when restoring the data for one image, the thinned image data, and the remaining image data, the console 58 also receives information such as the number of the table used from the radiographic image capturing apparatus 1. Instead, it is possible to select a table of Huffman codes to be used based on the photographing order information itself.

  Further, as described above, when the radiographic imaging device 1 is configured to transmit a Huffman code table suitable for the radiographic imaging conditions from the console 58 side, which is an external device, every radiographic imaging. When the compressed image data, compressed thinned-out image data, and uncompressed image data composed of differential data compressed with reference to the table are transferred from the radiation image capturing apparatus 1, the data for one image is transferred. When restoring the thinned-out image data and the remaining image data, the console 58 is configured to perform decompression processing and restoration processing with reference to the same Huffman code table as that transmitted to the radiographic imaging apparatus 1. It is also possible.

  On the other hand, it is also possible to create a Huffman code table each time the radiation image capturing apparatus 1 performs compression processing on the difference data. In this case, the console 58 refers to the Huffman code table transferred together with the Huffman code from the radiation image capturing apparatus 1 when restoring the data for one image, the thinned image data, and the remaining image data. In the same manner as described above, the original difference data is restored and the data for one image, the thinned image data, and the remaining image data are restored.

  In this case, the reference data Dc (0, m) and Dc (b, 0) may be created each time the radiographic image capturing apparatus 1 performs the compression process on the difference data. On the other hand, the console 58 restores the original difference data in the same manner as described above based on the reference data transferred together with the Huffman code table, for example, for one image data, thinned image data, and remaining image data. Configured to restore data.

  Next, the operation of the radiographic image capturing apparatus 1 and the radiographic image capturing system 50 according to the present embodiment will be described.

The control means 22 of the radiographic image capturing apparatus 1 compresses the data for one image composed of all the image data for one image output from the plurality of readout circuits 17 to transmit it to an external device such as the console 58. When creating the data for one image, the difference data is created by calculating the difference between the image data read from the radiation detection elements 7 adjacent in the signal line direction for each image data constituting the data for one image. The compressed data for one image is created by performing compression processing on the difference data.
Here, in this embodiment, when the control means 22 of the radiographic image capturing apparatus 1 is instructed to transmit data for one image from an external device such as the console 58 or the console 57 to the external device such as the console 58. It is assumed that when one compressed image data is created or when compressed thinned image data is created, compressed one image data is automatically created.

  When the data for one compressed image is transferred from the radiographic imaging apparatus 1, the console 58 (specifically, the control unit 58 b of the console 58) decompresses the compressed one image data into the original difference data. Then, the original image data is restored based on the difference data. A diagnostic radiation image or the like is generated based on the restored one-image data by performing image correction processing such as offset correction processing, gain correction processing, and defective pixel correction processing on the restored one-image data. It is configured to display on the display unit 58a.

  Note that the console 58 can also generate a preview image based on the restored data for one image. That is, it is also possible to perform a thinning process on the restored one-image data and generate a preview image based on the one-image data on which the thinning process has been performed.

  Here, according to the study by the inventors of the present application, each image data constituting one image data is read from the image data adjacent in the scanning line direction, that is, read from the radiation detection elements 7 adjacent to each other in the scanning line direction. It was found that the difference data created by calculating the difference between the image data is distributed over a relatively wide range.

  Thus, in order to clarify the cause of the difference data in the scanning line direction being distributed over a relatively wide range, the same scanning is performed when the radiation imaging apparatus 1 is uniformly irradiated with radiation without passing through the subject. Image data D (n, 1) read from each radiation detection element (n, 1), (n, 2), (n, 3), (n, 4),. ), D (n, 2), D (n, 3), D (n, 4),... Were calculated, and the distribution of the difference data as shown in FIG. 19 was obtained. In FIG. 19 and FIG. 20 described later, the vertical axis represents the appearance frequency F of the difference data ΔD.

  As shown in FIG. 19, each radiation detection element (n, 1), (n, 2), (n, 3), (n, 4),... Connected to the line Ln of the same scanning line 5 has the same dose. Despite being irradiated with the same amount of radiation or with the same intensity of electromagnetic waves converted by the scintillator 3 that has been irradiated with the same dose of radiation It can be seen that each difference data of the image data D (n, 1), D (n, 2), D (n, 3), D (n, 4),... Is distributed in a relatively wide range.

  The reason why the distribution of the difference data becomes wide is due to the manufacturing variation of each radiation detecting element 7 formed by stacking each layer as shown in FIG. Further, according to the manufacturing variation of each radiation detecting element 7, it should be a normal distribution centered on ΔD = 0, but as long as the distribution shown in FIG. Rather, the distribution can be said to be trapezoidal.

  The main cause of the difference data distribution of the image data read from each radiation detection element 7 connected to the line Ln of the same scanning line 5 as shown in FIG. It is considered that the output characteristics of the readout circuit 17 that reads image data from the detection element 7 are different for each readout circuit 17 and the output characteristics of the readout circuits 17 vary.

  That is, in the present embodiment, as shown in FIG. 9, a total of 2048 readout circuits 17 formed in each readout IC 16 are provided. In each readout circuit 17, the charge-voltage conversion characteristics of the amplifier circuit 18 are provided. And the output characteristics of the readout circuit 17 in which the sampling characteristics of the correlated double sampling circuit 19 are integrated. For this reason, even if the image data sent from each radiation detection element 7 to each readout circuit 17 has the same value, it is considered that the image data output by charge-voltage conversion in each readout circuit 17 has a different value.

  Note that the difference that occurs in the image data due to the difference in the output characteristics of each readout circuit 17 is, for example, transferred to an external device such as the console 58 and then image data (more precisely, from the image data) during the image correction processing. It is eliminated or reduced by adjusting the gain correction value for each readout circuit 17 that multiplies the value obtained by subtracting the offset.

In the trapezoidal distribution as shown in FIG. 19, the appearance frequency is relatively high even in the difference data other than the difference data in the portion of ΔD = ± α (α ≠ 0) to which the highest occurrence frequency and the shortest Huffman code are assigned. .
Therefore, if a Huffman code is assigned to each differential data having a distribution as shown in FIG. 19, the number of differential data to which a Huffman code not so short is assigned increases. For this reason, it is considered that the compression rate of the differential data does not become so high.

  On the other hand, the image data D read from each radiation detection element (1, m), (2, m), (3, m), (4, m),... Connected to the same signal line 6. Each difference data of (1, m), D (2, m), D (3, m), D (4, m),... Is distributed in a relatively narrow range as shown in FIG. It turned out that it becomes distribution of normal distribution centering on = 0.

  As can be seen from the configuration shown in FIG. 7, each of the radiation detection elements (1, m), (2, m), (3, m), (4, m) connected to the same signal line 6 is understood. ),... Are output from the image data D (1, m), D (2, m), D (3, m), D (4, m),. Therefore, the influence of the variation in the output characteristics of the readout circuits 17 as described above does not appear in the distribution of the difference data. Therefore, in this case, it is considered that only the influence due to the manufacturing variation of each radiation detection element 7 is reflected, and the distribution of the difference data becomes a normal distribution as shown in FIG.

In the normal distribution as shown in FIG. 20, the appearance frequency of the difference data of ΔD = 0 to which the shortest Huffman code is assigned is very large, and the appearance frequency of the difference data to which other longer Huffman codes are assigned. Becomes smaller.
Therefore, if a Huffman code is assigned to each differential data having a distribution as shown in FIG. 20, the number of differential data to which a short Huffman code is assigned increases, and the compression rate of the differential data is considered to improve. That is, when creating data for one compressed image, if the difference is taken in the signal line direction as in this embodiment, the compression rate is improved compared to the case where the difference is taken in the scanning line direction.

Further, the control means 22 of the radiographic image capturing apparatus 1 transmits thinned image data created by performing thinning processing in the signal line direction at a predetermined ratio to one image data to an external device such as the console 58. Therefore, when creating compressed thinned image data, the difference between the image data read from the radiation detection elements 7 adjacent in the scanning line direction is calculated for each image data constituting the thinned image data. Difference data is created, and the compressed thinned image data is created by compressing the difference data.
Here, in the present embodiment, when the control means 22 of the radiographic image capturing apparatus 1 is instructed to transmit thinned image data from an external device such as the console 58 or the console 57 to the external device such as the console 58. It is assumed that the compressed thinned image data is created or the compressed thinned image data is automatically created when shooting is completed.

  When the compressed thinned image data is transferred from the radiographic imaging apparatus 1, the console 58 (specifically, the control unit 58b of the console 58) decompresses the compressed thinned image data into the original difference data. Then, the original thinned-out image data is restored based on the difference data. Then, the restored thinned image data is stored in the ROM or the storage means 59 provided in the control unit 58b, and the restored thinned image data is subjected to offset correction processing, gain correction processing, defective pixel correction processing, and the like. A preview image or the like is generated based on the restored thinned image data by performing an image correction process or the like, and is displayed on the display unit 58a.

  Note that when generating a preview image, the console 58 further performs a thinning process on the restored thinned image data, and generates a preview image based on the thinned image data on which the thinning process has been performed. It is also possible to do.

  Here, according to the study of the present inventors, for each image data constituting the thinned image data, the difference data distribution created by calculating the difference between the image data adjacent in the signal line direction, and the scanning line direction Compared with the distribution of the difference data created by calculating the difference between the image data adjacent to each other, the difference between the image data adjacent in the scanning line direction is calculated unlike the case of creating the data for one compressed image. The difference data created in this way was found to be distributed in a narrower range.

  This is because when image data for compression thinning is created, the image data adjacent in the scanning line direction are image data D (b, 1) and D (b, 2), and image data D (b, 2) and D ( b, 3),... are image data read from the radiation detecting elements 7 adjacent to each other. On the other hand, the image data adjacent in the signal line direction is image data extracted every predetermined number of lines (every three lines in the present embodiment). Therefore, in this embodiment, the image data D (1 , M) and D (5, m), image data D (5, m) and D (9, m),..., Which are considered to be because they are not image data read from the radiation detecting elements 7 adjacent to each other.

  That is, if the pixel position is separated, there is a high possibility that the difference between the pixel values is large. Therefore, if the positions of the radiation detection elements 7 and 7 are separated, difference data between the image data read from the radiation detection elements 7 and 7 is obtained. Is more likely to deviate from ΔD = 0. As the difference between the pixel values increases, the distribution of the difference data greatly affects more than the variation in the output characteristics of each readout circuit 17. Therefore, when creating the compressed thinned image data, the difference is taken in the signal line direction, that is, the position The difference between the image data read from the radiation detection elements 7 and 7 separated from each other takes the difference in the scanning line direction, that is, the image data read from the radiation detection elements 7 and 7 adjacent to each other. It is considered that the distribution of the distribution of the difference data is larger than the difference between the two.

  Therefore, when creating compressed thinned-out image data, if difference data in the signal line direction is created, the number of difference data to which a not so short Huffman code is assigned increases, so the compression rate of the difference data does not increase so much. On the other hand, when the difference data in the scanning line direction is created, the number of difference data to which a short Huffman code is assigned increases, so that the compression rate of the difference data is considered to improve. That is, when creating the compressed thinned image data, if the difference is taken in the scanning line direction as in this embodiment, the compression rate is improved compared to the case where the difference is taken in the signal line direction.

Further, the control means 22 of the radiographic image capturing apparatus 1 creates compressed residual image data in order to transmit the residual image data after the thinning processing of one image data to an external device such as the console 58. In this case, for each image data constituting the remaining image data, the difference between the image data read from the radiation detection elements 7 adjacent in the signal line direction is calculated to create difference data, and the difference data is compressed. By performing the process, the compressed image data is generated.
Here, in this embodiment, when the control unit 22 of the radiographic image capturing apparatus 1 is instructed to transmit the remaining image data from an external device such as the console 58 or the console 57 to the external device such as the console 58. It is assumed that the apparatus is configured to automatically generate uncompressed image data when the uncompressed image data is created or when the compressed thinned image data is created.

  When the uncompressed image data is transferred from the radiographic image capturing apparatus 1, the console 58 (specifically, the control unit 58 b of the console 58) decompresses the uncompressed image data into the original difference data. Then, the original remaining image data is restored based on the difference data. Then, the restored remaining image data and the thinned image data restored in advance and stored in the ROM or the storage means 59 provided in the control unit 58b are synthesized to create synthesized data, and the synthesized data On the other hand, image correction processing such as offset correction processing, gain correction processing, and defective pixel correction processing is performed to generate a diagnostic radiation image or the like based on the combined data, and display it on the display unit 58a. ing.

  Here, according to the present inventors' research, for each image data constituting the remaining image data, the difference data distribution created by calculating the difference between the image data adjacent in the signal line direction, and the scanning line direction When the difference data distribution calculated by calculating the difference between the image data adjacent to each other is compared, the difference between the image data adjacent in the signal line direction is calculated as in the case of generating the data for one compressed image. It was found that the difference data created in this way is distributed in a narrower range.

  This is presumably because the uncompressed image data is more similar to the compressed image data than the compressed thinned image data.

  That is, the remaining image data is image data other than the image data extracted every predetermined number of lines (every three lines in this embodiment). Therefore, in this embodiment, when creating the data for the remaining compressed image, the image data adjacent in the signal line direction are the image data D (b−1, m) and D (b + 1, m), and the image data D (b + 1). , M) and D (b + 2, m), and image data D (b + 2, m) and D (b + 3, m). The image data D (b−1, m) and D (b + 1, m) are not image data read from the radiation detecting elements 7 adjacent to each other, but the image data D (b + 1, m) and D (b + 2, m) ), Image data D (b + 2, m) and D (b + 3, m) are image data read from the radiation detecting elements 7 adjacent to each other.

Further, although the image data D (b−1, m) and D (b + 1, m) are not image data read from the radiation detecting elements 7 adjacent to each other, the image data D (1, m) described above are used. D (5, m), image data D (5, m) and D (9, m),... Are image data read from the radiation detection elements 7 and 7 that are not separated from each other.
That is, the distance between the radiation detection element (b-1, m) and the radiation detection element (b + 1, m) is the distance between the radiation detection element (1, m) and the radiation detection element (5, m). Or it is shorter than the distance between a radiation detection element (5, m) and a radiation detection element (9, m). In other words, the distance between the pixel position (b−1, m) and the pixel position (b + 1, m) is the distance between the pixel position (1, m) and the pixel position (5, m) It is shorter than the distance between the position (5, m) and the pixel position (9, m).

Therefore, the difference between the data values of the image data D (b−1, m) and D (b + 1, m) is the difference between the data values of the image data D (1, m) and D (5, m), It is considered that the difference between the data values of the image data D (5, m) and D (9, m) is smaller. In other words, the pixel value difference between the pixel position (b-1, m) and the pixel position (b + 1, m) is the pixel between the pixel position (1, m) and the pixel position (5, m). It is considered that the difference is smaller than the difference in values and the difference in pixel values between the pixel position (5, m) and the pixel position (9, m).
Therefore, when creating the data for the remaining compressed image, as in the case of creating the data for one compressed image, it is considered that the variation in the output characteristics of each readout circuit 17 greatly affects the distribution of the difference data.

  For this reason, when creating the uncompressed image data, if the difference data in the scanning line direction is created, the number of difference data to which a not-short Huffman code is assigned increases, so the compression rate of the difference data does not increase so much. On the other hand, if difference data in the signal line direction is created, the number of difference data to which a short Huffman code is assigned increases, so the compression rate of the difference data is considered to improve. That is, when creating the data for the remaining compressed image, if the difference is taken in the signal line direction as in the present embodiment, the compression rate is improved compared to the case where the difference is taken in the scanning line direction.

  As described above, according to the radiographic image capturing apparatus 1 according to the present embodiment, when data for one compressed image or data for an uncompressed image is created, the difference data in the signal line direction, that is, the same signal line 6 is used. When creating difference data of each image data read from a plurality of connected radiation detection elements 7 and performing compression processing on the difference data to create compressed thinned image data, the scanning line direction Difference data, that is, difference data of image data read from a plurality of radiation detection elements 7 connected to the same scanning line 5, and compression processing is performed on the difference data. . That is, it is configured to switch between taking a difference in the signal line direction and taking a difference in the scanning line direction according to the type of compressed image data to be created.

  With this configuration, when creating data for one compressed image or data for an uncompressed image, compression processing is performed on difference data of each image data read by the same read circuit 17. Therefore, it is possible to prevent the distribution of the difference data from spreading due to the variation in the output characteristics of each readout circuit 17 and to reduce the compression rate, and to create compressed thinned image data. Since the compression processing is performed on the difference data of the respective image data read from the radiation detection elements 7 adjacent to each other, the distribution of the difference data depends on the difference in the pixel values with the distance between the radiation detection elements. It is possible to prevent the compression ratio from being reduced and the compression ratio to decrease, and the compression ratio when compressing differential data of image data acquired by radiographic imaging is accurately improved. So it becomes possible.

  In addition, since the differential data can be compressed at a high compression rate as in this embodiment, the amount of data to be transferred is reduced and the transfer time is shortened, so that power consumption can be reduced. Become. In particular, when the radiographic imaging apparatus 1 is a battery built-in type as shown in the present embodiment, since the power consumption of the battery 41 is reduced, the radiographic imaging apparatus 1 is used for a longer time with one charge. Thus, the use efficiency of the radiation image capturing apparatus 1 can be improved.

  In the present embodiment, as a Huffman code table, one common table is provided for each signal line 6 or each line Lb of the scanning line 5, and this common table is referred to when assigning a Huffman code to difference data. However, for example, a Huffman code table may be provided for each signal line 6 or for each line Lb of the scanning line 5. Further, for example, the detection unit P may be divided into a plurality of regions extending in the signal line direction or the scanning line direction, and a Huffman code table may be provided for each division of the regions.

  In the present embodiment, as described above, a table of a plurality of types of Huffman codes is stored in advance in the ROM or the like of the radiation image capturing apparatus 1 for each type or imaging condition, and the control unit that constitutes the creation unit 22 describes the case where the data is compressed by performing Huffman encoding of the difference data with reference to the table during the compression process, but the present invention is not limited to this. Instead of creating a table, a Huffman code table is created based on the obtained difference data, and the Huffman coding of the difference data is performed by referring to the created table to compress the data. It is also possible to configure.

Specifically, before compressing the created difference data, the stored difference data is temporarily stored in the buffer memory 44c (see FIG. 12, etc.), and the created difference data is stored in the buffer memory 44c. The values are voted on the histogram, and at the stage where all the created difference data is stored in the buffer memory 44c, the distribution of the difference data as shown in FIG. 20 and the like is completed on the histogram.
Based on the distribution of the difference data, the control unit 22 creates a Huffman code table by assigning a Huffman code to each value of the difference data so that data having a higher appearance frequency is assigned a shorter Huffman code. . Then, each difference data is read from the buffer memory 44c, a Huffman code corresponding to each difference data is assigned, and each Huffman code which is the compressed difference data is stored and accumulated again in the buffer memory 44c. In this case, a plurality of buffer memories 44c, for example, one for differential data and one for Huffman code may be provided.

With this configuration, even if a Huffman code table is not created in advance, a Huffman code table is created based on the created difference data, and the Huffman coding of the difference data is performed by referring to the table. Data compression processing can be performed.
In this case as well, a Huffman code table is created for each signal line 6 or for each line Lb of the scanning line 5, and a plurality of detectors P are extended in the signal line direction or the scanning line direction. It is also possible to divide into areas and create a Huffman code table for each area.

  Further, in this case, when transferring from the radiographic image capturing apparatus 1 Huffman code, that is, compressed one-image data composed of compressed difference data, compressed thinned-out image data, and uncompressed image data, to the external apparatus, the radiation It is also necessary to transfer the information of the Huffman code table created by the image capturing device 1 to the external device. Therefore, in this case, the information of the generated Huffman code table is reversibly compressed and transmitted to the external device together with the Huffman code.

  Further, as described above, according to the radiographic image capturing system 50 according to the present embodiment, the compressed differential data transferred from the radiographic image capturing apparatus 1 is restored so as to completely match the original differential data. Therefore, it is possible to reliably restore each image data of the radiographic image captured by the radiographic image capturing apparatus 1.

  Also in the radiographic imaging system 50 according to the present embodiment, the radiographic imaging device 1 switches between taking a difference in the signal line direction or taking a difference in the scanning line direction depending on the type of compressed image data to be created. Therefore, the differential data can be compressed at a high compression rate, and the data transfer time is shortened and the power consumption is reduced. Therefore, even when viewed as the entire system, it is possible to shorten the data transfer time and reduce power consumption.

  According to the radiographic image capturing apparatus 1 and the radiographic image capturing system 50 according to the present embodiment described above, the radiographic image capturing system 50 generates a predetermined ratio with respect to data for one image when creating compressed thinned image data. The thinned image data is created by performing the thinning process in the signal line direction, and the image data read from the radiation detection elements 7 adjacent to each other in the scanning line direction is created for each image data constituting the thinned image data. When the difference is calculated and difference data is created, the compressed thinned image data is created by performing compression processing on the difference data, and the data for one compressed image is created, the data for one image is configured. The difference data is calculated by calculating the difference between the image data read from the radiation detecting elements 7 adjacent in the signal line direction for each image data. When creating the compressed one-image data by creating and compressing the difference data, and creating the remaining compressed image data, each image data constituting the remaining image data after the thinning process The difference between the image data read from the radiation detection elements 7 adjacent to each other in the signal line direction is calculated to create difference data, and the difference data is subjected to compression processing to generate the uncompressed image data. Is configured to do.

That is, the radiographic image capturing apparatus 1 is configured to switch between taking a difference in the signal line direction and taking a difference in the scanning line direction according to the type of compressed image data to be created.
Therefore, when creating one compressed image data or uncompressed image data, a compression process is performed on the difference data of each image data read by the same readout circuit 17. It is possible to prevent the distribution of differential data from spreading and the compression ratio from being lowered depending on the output characteristic variation, and when creating compressed thinned image data, the radiation adjacent to each other Since the compression process is performed on the difference data of each image data read from the detection element 7, the distribution of the difference data spreads depending on the distance between the radiation detection elements 7 and the compression rate decreases. Therefore, it is possible to accurately improve the compression rate when compressing difference data of image data acquired by radiographic imaging.

  In addition, since the difference data can be compressed at a high compression rate, the amount of data to be transferred is reduced and the transfer time is also shortened. Therefore, the power consumption of the radiographic imaging apparatus 1 and the radiographic imaging system 50 as a whole. Can be reduced.

  Further, according to the radiographic image capturing system 50 according to the present embodiment described above, when the compressed thinned image data is transferred from the radiographic image capturing apparatus 1, the console 58 stores the compressed thinned image data. When decompressed to the original difference data, the original thinned image data is restored based on the difference data, and data for one compressed image is transferred from the radiation image capturing apparatus 1, the data for the one compressed image Is decompressed into the original difference data, the original image data is restored based on the difference data, and when the compressed image data is transferred from the radiation image capturing apparatus 1, the compressed image data is compressed. The data is decompressed into the original difference data, and the original remaining image data is restored based on the difference data.

  Therefore, the console 58 completely matches the compressed difference data constituting the compressed one-image data, the compressed thinned-out image data, and the uncompressed image data transferred from the radiation image capturing apparatus 1 with the original difference data. Thus, the image data of the radiographic image captured by the radiographic image capturing apparatus 1 can be reliably recovered.

  Further, according to the radiographic imaging system 50 according to the present embodiment described above, the console 58 is configured to generate a preview image based on the restored thinned image data and display the preview image on the display unit 58a. In addition, a diagnostic radiographic image can be generated based on restored one-image data, or synthesized data obtained by synthesizing the restored thinned image data and the restored remaining image data. It is configured.

  Needless to say, the present invention is not limited to the above-described embodiment, and can be appropriately changed without departing from the gist of the present invention.

For example, in the above embodiment, the thinning-out image data is configured to be thinned out at a rate of 1/4 for one image data. However, the thinning-out rate is not limited to 1/4. , 1/2 or less is optional.
Further, when the thinning ratio is ½, when creating the remaining compressed image data, the difference in the scanning line direction may be taken as in the case of creating the compressed thinned image data. . That is, when the thinning ratio is ½, both the thinned image data and the remaining image data are data created by extracting the image data arranged in the scanning line direction every other line. Therefore, in this case, when the difference data is created from the remaining image data, if the difference is taken in the signal line direction, the difference between the image data read from the radiation detection elements 7 adjacent to each other cannot be taken. A difference may be taken in the scanning line direction so that the difference between the image data read from the radiation detecting elements 7 adjacent to each other can be obtained.

  Moreover, in the said embodiment, although the radiographic imaging device 1 was comprised so that the data for compression 1 image, the data for compression thinning | decimation image, and the data for compression remaining images may be produced, the data for compression 1 image or the compression remaining image is comprised. It is possible to configure so that no business data is created. That is, it may be configured to create one compressed image data and compressed thinned image data, or may be configured to create compressed thinned image data and uncompressed image data.

DESCRIPTION OF SYMBOLS 1 Radiographic imaging apparatus 5 Scanning line 6 Signal line 7 Radiation detection element 17 Reading circuit 22 Control means (preparation means)
39 Antenna device (transfer means)
44 Register section (creating means)
50 Radiation imaging system 58 Console (external device)
58a Display part P Detection part r area

Claims (6)

A plurality of scanning lines and a plurality of signal lines arranged so as to cross each other, and a plurality of radiation detection elements arranged in a two-dimensional manner in each region partitioned by the plurality of scanning lines and the plurality of signal lines A detection unit comprising:
A plurality of readout circuits for reading out charges from the radiation detection elements through the signal lines and outputting the charges as image data for each of the radiation detection elements;
Creating means for creating compressed thinned-out image data and compressed one-image data based on one-image data composed of each image data output from the plurality of readout circuits;
The creating means includes
When creating the compressed thinned image data, thinned image data is created by performing thinning processing in the extending direction of the signal line at a predetermined ratio with respect to the data for one image, and the thinned image data The difference between the image data read from the radiation detection elements adjacent in the extending direction of the scanning line is calculated for each of the image data constituting the difference data, and compression processing is performed on the difference data. To create the compressed thinned image data,
When creating the compressed image data, the difference between the image data read from the radiation detection elements adjacent in the signal line extending direction is calculated for each image data constituting the image data. A radiographic imaging apparatus, wherein differential data is generated and data for one compressed image is generated by performing compression processing on the differential data. A plurality of scanning lines and a plurality of signal lines arranged so as to cross each other, and a plurality of radiation detection elements arranged in a two-dimensional manner in each region partitioned by the plurality of scanning lines and the plurality of signal lines A detection unit comprising:
A plurality of readout circuits for reading out charges from the radiation detection elements through the signal lines and outputting the charges as image data for each of the radiation detection elements;
Creating means for creating compressed thinned image data and uncompressed image data based on one image data composed of each image data output from the plurality of readout circuits;
The creating means includes
When creating the compressed thinned image data, thinned image data is created by performing thinning processing in the extending direction of the signal line at a predetermined ratio with respect to the data for one image, and the thinned image data The difference between the image data read from the radiation detection elements adjacent in the extending direction of the scanning line is calculated for each of the image data constituting the difference data, and compression processing is performed on the difference data. To create the compressed thinned image data,
When creating the compressed residual image data, image data read from the radiation detection elements adjacent to each other in the signal line extending direction for each image data constituting the residual image data after the thinning process A radiographic imaging apparatus, wherein difference data is created by creating a difference, and the compression residual image data is created by performing compression processing on the difference data. The radiographic imaging apparatus according to claim 1, further comprising a transfer unit that transfers the compressed thinned image data and the compressed one-image data generated by the generating unit to an external device;
When the compressed thinned image data is transferred from the radiation image capturing apparatus, the compressed thinned image data is decompressed to the original difference data, and the original thinned image data is based on the difference data. When the compressed image data is transferred from the radiographic imaging device, the compressed image data is decompressed into the original difference data, and the original data is based on the difference data. A radiographic imaging system comprising: a console for restoring data for one image.   The console generates a preview image based on the restored thinned image data and displays the preview image on a display unit, and generates a diagnostic radiation image based on the restored one-image data. 3. The radiographic imaging system according to 3. The radiographic image capturing apparatus according to claim 2, further comprising a transfer unit that transfers the compressed thinned image data and the compressed uncompressed image data created by the creating unit to an external device;
When the compressed thinned image data is transferred from the radiation image capturing apparatus, the compressed thinned image data is decompressed to the original difference data, and the original thinned image data is based on the difference data. And when the compressed residual image data is transferred from the radiographic imaging device, the compressed residual image data is decompressed to the original difference data, and the original data based on the differential data is extracted. A radiographic imaging system comprising: a console for restoring remaining image data.   The console generates a preview image based on the restored thinned image data, displays the preview image on a display unit, and combines the restored thinned image data and the restored remaining image data. 6. The radiographic image capturing system according to claim 5, wherein a diagnostic radiographic image is generated based on the radiographic image.

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