JP4136063B2 - Radiation imaging device - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a radiation imaging apparatus including an apparatus that displays an X-ray digital image that has been captured and stored.
[0002]
[Prior art]
In the field of medical diagnostic imaging equipment, digital technology has advanced rapidly, and radiation image detectors using semiconductor X-ray surface sensors have been developed in place of X-ray films and imaging plates used in simple X-ray imaging equipment. Yes. This X-ray surface sensor is usually composed of an X-ray conversion film for converting X-rays into light, a photodiode array, and a TFT switch. After X-ray irradiation, signal charges accumulated in each pixel are read out. A line image is formed.
[0003]
A method for fetching into a general image storage device and a method for displaying it on a display device will be described with reference to FIGS. The radiological image detection unit of FIG. 4 switches a photoelectric conversion unit composed of a scintillator that converts X-rays into light and a photodiode that receives the light and generates a charge signal as one pixel of the X-ray image, and switches the signal. It is composed of a thin film transistor TFT that goes out. Depending on how these pixels are arranged in a given dimension, the resolution of the image is determined geometrically. Then, the charge pattern is sequentially sent to the scanning line by the scanning pulse generator of the signal readout circuit, the TFT is switched, and the charge signal of the photodiode is sequentially sent to the transfer register via the signal line.
[0004]
An X-ray charge image signal is input in time series from the transfer register to the input buffer of the image memory (RAM). The write circuit operates by the WRITE input signal and the chip selector signal from the control bus, and the data enters the memory cells in the matrix configuration. The matrix memory cell is a buffer memory corresponding to one image page and is used as a page memory (frame memory). The memory size is determined by the size of the image, and the pixel size is expressed as, for example, 2048 × 2048.
When storing the image in this frame memory, it is transferred to a large image storage device (magnetic disk) by a data bus by a READ input signal and a chip selector signal from the control bus, and recorded by this route for every imaging.
[0005]
Next, when displaying on the image display device (CRT), reading from the frame memory is similarly performed by a READ input signal and a chip selector signal from the control bus. The data reading unit 60 shown in FIG. 5 performs the address control B according to the reading start origin of the frame memory stored in the address register and the size (horizontal direction and vertical direction) of the frame memory, and the image data in the memory is stored. The data is taken into the reading register B (reading means) and sequentially stored in the refresh memory B20 (RAM video memory) by the data bus.
[0006]
Then, the memory control 9 generates a read control signal for the refresh memory B20 by a signal from the display timing generation unit 10, while the video signal generation unit B23 reads the read signal from the refresh memory B20 and the display timing from the display timing generation unit 10. In response to the signal, a video signal is generated. The display device CRT-B 26 receives the video signal and displays an image by non-interlaced scanning or interlaced scanning.
[0007]
If necessary, the image data is output to the image hard copy device 5 in the same manner.
[0008]
[Problems to be solved by the invention]
The conventional radiation imaging apparatus is configured as described above, but the image data output from the radiation image detection unit 1 is temporarily transferred to the buffer memory 3 (frame memory), and the image storage device (magnetic disk) 4 or the image is stored. The image display device CRT is transferred to the display device CRT-B26 or the image hard copy device 5, and there are various image display devices CRT having various resolutions from a high-resolution monitor for medical use to a low-resolution monitor for personal computers. There was a problem that the size of did not necessarily match. In particular, when the radiation image detection unit 1 is intended to capture both moving images and still images, for example, when outputting to a video monitor in the case of a moving image and to a laser imager in the case of a still image, There is a need for data transfer means that can accommodate devices of different resolutions.
[0009]
The present invention has been made in view of such circumstances, and an object of the present invention is to provide a radiographic imaging apparatus capable of transferring or displaying or recording image data simultaneously or sequentially to devices having different resolutions. And
[0010]
[Means for Solving the Problems]
In order to achieve the above object, a radiation imaging apparatus according to the present invention includes a memory for storing captured pixel data and pixel data in the memory in a radiation imaging apparatus including a one-dimensional or two-dimensional semiconductor radiation sensor array. Data reading means for reading
Calculation means for inputting pixel data read from the data reading means, a plurality of refresh memories for storing pixel data calculated by the calculation means, and a video signal generation connected to each of the plurality of refresh memories And an image display device that is connected to each of the video signal generators and displays an image, and the calculation means compresses or enlarges the image according to the resolution of the image display device. It is characterized by that.
[0011]
Further, the data reading means reads only partly specific pixel data of the image data.
[0012]
Further, for the different said image display device resolution, and having the different numbers only provided a process control line.
[0013]
In addition, the image display device includes a moving image display device and a still image display device.
[0014]
In addition, it is characterized in that a portion where the imaged pixel data is not in the memory is interpolated and reduced (enlarged) by using the pixel data of the peripheral portion.
[0015]
The radiation imaging apparatus of the present invention is configured as described above, and the calculation means performs reduction or enlargement calculation processing, the data reading means reads only a part of specific pixel data of the image data, or the imaged pixels Interpolation calculation is performed on peripheral data for parts with missing data, and multiple calculation means are provided according to display devices with different resolutions, and moving images and still images are displayed simultaneously or sequentially on the display device. Necessary images can be displayed.
[0016]
DETAILED DESCRIPTION OF THE INVENTION
An embodiment of the radiation imaging apparatus of the present invention will be described with reference to FIG.
[0017]
In FIG. 1, the radiation imaging apparatus includes an image generation unit including a radiation image detection unit 1 and a signal readout circuit 2, an image including a buffer memory 3 (frame memory) that temporarily captures the image, and an image storage device 4. The memory unit and a processing control unit that controls the image data in the buffer memory 3 and transfers the image data to the display devices CRT-A25, B26, and C27.
[0018]
The processing control unit includes a register unit 40 that stores an address value of the buffer memory 3, a data reading unit 60 that reads image data from the buffer memory 3, and a calculation unit 50 that performs compression operation A or expansion operation C on the read data. And refresh memories (RAM video memories) A19, B20, C21 having a memory size corresponding to the resolution of the display device, video signal generators A22, B23, C24, and display timing generation for taking the display timing of each line The image display unit 25, the image display devices 25, 26, and 27 have different resolutions.
Next, the signal flow of the processing control unit will be described. The data reading unit 60 performs the address control A, B, C on the image data in the buffer memory 3 according to the address register values (41, 42), (43, 44) stored in the register unit 40, and stores them in the memory. Are read into reading registers A, B, and C (reading means) and sent to the arithmetic unit 50 via a data bus.
[0019]
In the present invention, the read start origin (41, 42), the size of the original image, that is, the frame memory 3 (horizontal direction 43 and vertical direction 44), and the output image size (horizontal direction 45 and vertical direction 46) are stored in each address register of the register unit 40. ) Are stored respectively. The data reading unit 60 and the calculation unit 50 read the image data in the frame memory based on the stored address register value and perform calculation processing.
[0020]
The arithmetic unit 50 performs compression / enlargement arithmetic operations A and C in accordance with the resolution of the display device in accordance with the register values (45, 46) of the register unit 40, and uses the data bus to refresh memories A19, B20, C21 (RAM video memory). Store data sequentially.
The processing control unit is provided with a different number of processing control lines for image display devices having different resolutions, and includes a data reading unit 60-an arithmetic unit 50-refresh memories A, B, C,-a video signal generation unit A, B, C, lines of the image display devices 25, 26, and 27 are configured, and the display timings of the lines are controlled by the display timing generator 10 and the memory control 9. By controlling in this way, it is possible to display simultaneously or sequentially on display devices having different resolutions.
[0021]
In the apparatus shown in FIG. 2, the specific area extraction 6 of the data reading unit 60 extracts only part of specific image data in the frame memory (buffer memory) by address control. This extraction is performed by storing the cut-out size (the horizontal direction 47 and the vertical direction 48) of the specific image in the register values (47, 48) of the register unit 40 and performing address control D. Only the extracted image data is subjected to the compression / enlargement operation A or C corresponding to the resolution of the display device CRT-D13 without transferring the peripheral image data unnecessary for display, and the entire extracted image is viewed. The data is stored in the refresh memory D11 (RAM) with a data bus at a compression rate. Then, the extracted image is displayed on the display device CRT-D13 via the video signal generator D12.
[0022]
Next, the compression / enlargement calculation will be described. For example, it is assumed that the number of pixels of the radiation image detection unit 1 is 2048 × 2048. On the other hand, it is assumed that the displayable size of the display device CRT is 400 × 400. In this case, normally, there is a problem that the transfer display cannot be performed due to the size mismatch, or there is a problem that a large amount of data unnecessary for display must be transferred even if display is possible. The size conversion from the number of pixels 2048 × 2048 to the displayable size 400 × 400 is performed as follows.
[0023]
The calculation is executed based on each register value of the register unit. First, the reading start origin (horizontal direction and vertical direction) on the buffer memory (frame memory) 3 is stored in the register. In this case, since all the pixels on the buffer memory 3 are to be read, “0” is stored in all of them. The next register stores the size (horizontal direction and vertical direction) of the original image to be read out. In this case, both are “2048”. The next register stores the output image size (horizontal direction and vertical direction). In this case, both are “400”. If the size of the output image is smaller than the size of the original image, the calculation operation is image reduction, and vice versa.
[0024]
Next, a calculation example with the exemplified numerical values is shown. First, a mapping operation from the original images B0, B1,... B2047 to the output image values A0, A1,. Specifically, with respect to the pixel Xi (i = 0, 1,..., 2047), an operation of i × 400 ÷ 2048 is performed, and the pixels whose integer part has the same value (i) are averaged and stored as Ai. It is. For example, since the image numbers 1019 to 1023 of the original image are all calculated as 199 by the above calculation, the value of A199 is determined by A199 = (B1019 + B1020 +... + B1023) ÷ 5. After performing this calculation in the horizontal direction of the image, the two-dimensional image size can be reduced and converted by performing the same calculation in the vertical direction. When the calculation is an enlargement calculation, the number of pixels may be increased in both the vertical and horizontal directions using spline interpolation or linear interpolation processing. FIG. 3 shows a schematic diagram of compression, enlargement, and specific area extraction.
[0025]
In the embodiment, the case where the original image size stored in the memory is 2048 × 2048 and the output size is 400 × 400 has been described, but the present invention is not limited to this size, and any size may be used. good. The same applies to the one-dimensional case.
Furthermore, in the embodiment, it is assumed that each pixel from the radiation image detection unit 1 to the frame memory 3 corresponds to one-to-one, but the sensor array pitch is further reduced and a plurality of sensor outputs are added in advance. In this case, the image data may be stored in a memory area for one pixel.
[0026]
In the image reduction (enlargement) calculation, if the corresponding sensor pixel is a defective pixel, the calculation can be performed using only the sensor pixel value in the peripheral portion without using the pixel value.
[0027]
If the apparatus involves changing the image size, the output data string can be coded according to a predetermined procedure, and can be easily changed by selecting the code.
[0028]
【The invention's effect】
The radiation imaging apparatus of the present invention is configured as described above, and can display X-ray images simultaneously or sequentially on image display apparatuses having various resolutions. For example, a moving image can be displayed on a monitor of a low-resolution personal computer, and only the important frames can be output to a high-resolution imager. In addition, only a specific area can be displayed on a necessary image display device with the same image size.
[Brief description of the drawings]
FIG. 1 is a diagram showing an embodiment of a radiation imaging apparatus of the present invention.
FIG. 2 is a diagram showing another embodiment of the radiation imaging apparatus of the present invention.
FIG. 3 is a diagram for explaining compression, enlargement, and specific extraction of an original image.
FIG. 4 is a diagram for explaining writing, reading, and display of digital data of a radiographic image.
FIG. 5 is a diagram showing a conventional radiation imaging apparatus.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 ... Radiation image detection part 2 ... Signal reading circuit 3 ... Buffer memory 4 ... Image storage device 5 ... Image hard copy device 6 ... Specific area extraction 9 ... Memory control 10 ... Display timing generation part 11 ... Refresh memory D
12 ... Video signal generator D
13 ... CRT-D
19 ... Refresh memory A
20 ... Refresh memory B
21 ... Refresh memory C
22 ... Video signal generator A
23 ... Video signal generator B
24 ... Video signal generator C
25 ... CRT-A
26 ... CRT-B
27 ... CRT-C
30 ... Original image 31 ... Compression calculation image 32 ... Enlarged calculation image 33 ... Specific area extraction image 40 ... Register unit 41 ... Read start origin X
42 ... Reading origin Y
43 ... Original image, that is, the size X of the frame memory 3
44 ... Original image, that is, the size Y of the frame memory 3
45 ... Output image size X
46 ... Output image size Y
47 ... Specific image output size X
48 ... Specific image output size Y
50 ... Calculation unit 60 ... Data reading unit

Claims (5)

In a radiation imaging apparatus comprising a one-dimensional or two-dimensional semiconductor radiation sensor array,
A memory for storing captured pixel data;
Data reading means for reading pixel data in the memory;
Arithmetic means for inputting pixel data read from the data reading means;
A plurality of refresh memories for storing pixel data calculated by the calculation means ;
A video signal generator connected to each of the plurality of refresh memories;
An image display device connected to each of the video signal generators for displaying an image;
The radiation imaging apparatus, wherein the calculation means performs a compression or enlargement calculation process on an image in accordance with the resolution of each of the image display apparatuses. The radiation imaging apparatus according to claim 1, wherein the data reading unit reads only partly specific pixel data of the image data. The radiation imaging apparatus according to claim 1, further comprising processing control lines provided in different numbers for the image display apparatuses having different resolutions . The radiation imaging apparatus according to claim 1, wherein the image display apparatus includes a moving image display apparatus and a still image display apparatus. 2. The radiation imaging apparatus according to claim 1, wherein a portion where the captured pixel data is not in the memory is interpolated and reduced (enlarged) by using the pixel data of the peripheral portion thereof.

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