JP2005295045A - Image display device - Google Patents

Abstract

Gradation reference image data corresponding to a reference gradation of a display image is quickly selected.
An image display device 1 of the present invention checks all image data of a region of interest in a DSA image P when selecting gradation reference image data corresponding to a reference gradation of a DSA image P that is a display image. do not do. Preliminarily selected as candidates for gradation reference image data for each divided section U set in advance for the entire DSA image, and corresponds to the region of interest from the reference candidate image data registered in association with each divided section U Tone reference image data is selected simply by extracting and checking only the reference candidate image data of the divided section U to be selected as candidate image data. The reference candidate image data to be checked is preliminarily selected from the image data of each divided section U of the image to be displayed, and the reference candidate image data to be checked is compared with the total number of image data for the region of interest. Since the total number is much smaller, it does not take time to read out the image data necessary for selecting the gradation reference image data, and the gradation reference image data can be selected quickly.
[Selection] Figure 1

Description

  The present invention selects specific image data from the display image as gradation reference image data corresponding to the reference gradation (reference density) of the display image, and selects the selected gradation reference image data as a reference gradation. In particular, the present invention relates to a technique for selecting gradation reference image data corresponding to a reference gradation of a display image.

  In the case of an image display apparatus incorporated in an X-ray imaging apparatus used in a medical institution such as a hospital, X-rays are extracted from image data on a region of interest set in advance for an X-ray image that is a display image. By selecting gradation reference image data corresponding to the reference gradation of the image and performing gradation conversion using the selected gradation reference image data as the reference gradation on the image data of the X-ray image, An X-ray image is displayed with appropriate contrast.

In the case of gradation conversion of image data in a conventional image display device, for example, the maximum value and the minimum value among image data in a region of interest set in advance for a display image are selected as gradation reference image data, As shown in FIG. 11, the image data having the maximum value MX is set to the maximum luminance gradation level (white density) HB, the image data having the minimum value MU is set to the minimum luminance gradation level (black density) LB, and the maximum value MX is set. And the minimum luminance value MU are assigned so that the density between the maximum luminance gradation level HB and the minimum luminance gradation level LB is proportional to the data value. Thereby, in the final image, the pixel corresponding to the image data of the maximum value MX is displayed brightest, the pixel corresponding to the image data of the minimum value MU is displayed darkest, and between the maximum value MX and the minimum value MU. As a result of displaying the pixels corresponding to the image data with a density proportional to the data value, the image is displayed with an appropriate contrast (see, for example, Patent Document 1).
JP 2000-79110 A (Page 7, FIGS. 6 and 7)

  However, the above-described conventional image display apparatus has a problem that it takes time to select gradation reference image data corresponding to the reference gradation of the display image.

  The image data of the region of interest set in advance for the display image is a considerable amount as the total number of data even if the region of interest is partial, and it takes time to read and check the image data from the image signal memory. It will take. It is usual that there are a plurality of regions of interest set in the display image. When there are a plurality of regions of interest, it takes a longer time to select the gradation reference image data.

  The present invention has been made in view of such circumstances, and an object thereof is to provide an image display apparatus capable of quickly selecting gradation reference image data corresponding to a reference gradation of a display image. To do.

  In order to achieve such an object, the present invention has the following configuration.

  That is, the image display device according to the first aspect of the present invention includes (A) a region of interest setting means for setting a region of interest for a display image, and (B) a gradation reference corresponding to the reference gradation of the display image. As candidate image data, reference candidate image data preliminarily selected for each divided section from among image data of a plurality of divided sections set in advance for the entire display image is associated with each divided section. The region of interest set by the region-of-interest setting unit among all the divided sections of the display image from among the reference candidate image data registered in the reference candidate image data registration unit to be registered and (C) the reference candidate image data registration unit Selection candidate image data extraction means for extracting the reference candidate image data of the divided sections corresponding to the selection candidate image data, and (D) selection candidate image data extracted by the selection candidate image data extraction means Tone reference image data selection means for selecting gradation reference image data from among them, and (E) gradation conversion using gradation reference image data selected by the gradation reference image data selection means as reference gradation And a tone converting means for applying to the image data.

  [Operation / Effect] In the image display apparatus according to the first aspect of the present invention, the gradation reference image data corresponding to the reference gradation of the display image is selected through the following process. First, the region of interest is set for the display image by the region of interest setting means, and a gradation reference corresponding to the reference gradation of the display image is set for each of a plurality of division sections set in advance for the entire display image. Reference candidate image data preliminarily selected from the image data of each divided section as image data candidates is registered in association with each divided section by the reference candidate image data registration means. Next, only the reference candidate image data of the divided section corresponding to the region of interest set by the region-of-interest setting unit from the reference candidate image data registered in the reference candidate image data registration unit is selected by the selection candidate image data extraction unit. Extracted as selection candidate image data. Further, the gradation reference image data selection means selects gradation reference image data from the selection candidate image data extracted by the selection candidate image data extraction means.

  That is, in the case of the image display device according to the first aspect of the invention, when selecting the gradation reference image data corresponding to the reference gradation of the display image, it is possible to check all the image data for the region of interest in the display image one by one. do not do. Preliminarily selected as candidates for gradation reference image data for each of a plurality of preset divisions for the entire display image and registered in the region of interest among the reference candidate image data registered in association with each division. The gradation reference image data is selected simply by extracting and checking the reference candidate image data of the corresponding divided section as selection candidate image data. The reference candidate image data to be checked is preliminarily selected from the image data of each divided section of the display image, and the total number of reference candidate image data to be checked is compared with the total number of image data for the region of interest. Since it is far less, it does not take time to read and check the image data necessary for selecting the gradation reference image data.

  According to a second aspect of the present invention, in the image display device according to the first aspect, (F) registration to the reference candidate image data registering unit for each of a plurality of division sections set in advance for the entire display image. The reference candidate image data selecting means for selecting the reference candidate image data to be selected without the image data reading process is provided in the preceding stage of the gradation converting means, and the reference candidate image data selected by the reference candidate image data selecting means is the reference candidate. It is registered in the image data registration means.

  [Operation / Effect] In the case of the image display device according to the second aspect of the present invention, the reference candidate image data is not accompanied by the image data reading process by the reference candidate image data selection means provided on the preceding stage of the gradation conversion means. Since it is configured to be selected and registered by the reference candidate image data registration means, the apparatus itself performs preliminary selection of the reference candidate image data to be registered without preventing the prompt selection of the gradation reference image data. Can do.

  According to a third aspect of the present invention, in the image display device according to the second aspect, (G) image data adjustment processing means for performing adjustment processing for adjusting each image data of the display image so that gradation conversion can be performed. The reference candidate image data selection means executes the selection process of the reference candidate image data without the image data reading process by using the adjustment process by the image data adjustment processing means. To do.

  [Operation / Effect] In the image display device according to the invention of claim 3, the reference candidate image data selection means is such that the image data adjustment processing means on the front side of the gradation conversion means converts the gradation of each image data of the display image. By using the adjustment process for adjusting the state to be able to be performed, it is possible to easily execute the selection process of the reference candidate image data without the image data read process.

  According to a fourth aspect of the present invention, in the image display device according to the third aspect, the piggybacking on the adjustment processing of the image data adjustment processing means of the reference candidate image data selection means is adjusted by the image data adjustment processing means. The reference candidate image data selection means directly uses the image data at a stage in which the gradation conversion can be performed by the standard candidate image data selection means.

  [Operation / Effect] In the case of the image display device according to the invention of claim 4, the reference candidate image data selection means obtains the image data at a stage where the gradation conversion by the adjustment processing can be performed by the image data adjustment processing means. By directly using for selection of the reference candidate image data, the adjustment processing of the image data adjustment processing means can be easily used.

  According to a fifth aspect of the present invention, in the image display device according to any one of the first to fourth aspects, the reference candidate image data selection means is an image having a maximum value and a minimum value in the image data for the divided sections. The data is preliminarily selected as reference candidate image data, and the gradation reference image data selection means selects the maximum and minimum image data extracted from the selection candidate image data extraction means by the gradation reference. This is selected as image data.

  [Operation / Effect] In the case of the image display device of the invention of claim 5, the reference candidate image data preliminarily selected by the reference candidate image data selection means is the maximum value and the minimum value in the image data for the divided sections. The gradation reference image data selected by the gradation reference image data selection unit is image data of the maximum value and the minimum value of the selection candidate image data extracted by the selection candidate image data extraction unit, As the gradation reference image data, the image data of the maximum value and the minimum value in the image data of the region of interest is selected. Therefore, the gradation conversion of the image data is substantially performed in the image data of the region of interest. This is performed based on the maximum and minimum image data.

  According to a sixth aspect of the present invention, in the image display device according to any one of the first to fifth aspects, the region of interest setting means can set a plurality of regions of interest for one image to be displayed. At the same time, when a plurality of regions of interest are set by the region of interest setting means, the selection candidate image data extracting means extracts the reference candidate image data of all the divided sections corresponding to the plurality of regions of interest as selection candidate image data. It is.

  [Operation / Effect] In the image display device according to the invention of claim 6, when a plurality of regions of interest are set by the region-of-interest setting unit for the display image, the selection candidate image data extracting unit corresponds to the plurality of regions of interest. Since the reference candidate image data of all the divided sections is extracted as the selection candidate image data, the region where the gradation reference image data may exist is set as the region of interest without omission, so that accurate gradation reference image data can be obtained. Selection can be made.

  In the case of the image display device of the present invention, when selecting the gradation reference image data corresponding to the reference gradation of the display image, all image data regarding the region of interest in the display image is not checked one by one. Preliminarily selected as candidates for gradation reference image data for each of a plurality of preset divisions for the entire display image and registered in the region of interest among the reference candidate image data registered in association with each division The gradation reference image data is selected simply by extracting and checking the reference candidate image data of the corresponding divided section as selection candidate image data. The reference candidate image data to be checked is preliminarily selected from the image data of each divided section of the display image, and the total number of reference candidate image data to be checked is compared with the total number of image data for the region of interest. Since it is far less, it does not take time to read and check the image data necessary for selecting the gradation reference image data.

  Therefore, according to the image display device of the present invention, the gradation reference image data corresponding to the reference gradation of the display image can be quickly selected.

  An embodiment of the present invention will be described with reference to the drawings. FIG. 1 is a block diagram showing the configuration of a DSA (digital subtraction angiography) type X-ray imaging apparatus incorporating an image display apparatus according to an embodiment of the present invention.

  The X-ray imaging apparatus of FIG. 1 includes an X-ray imaging system including an X-ray tube XA that irradiates a subject M with X-rays and a two-dimensional X-ray detector XD that detects a transmitted X-ray image of the subject M. The two-dimensional X-ray detector XD detects a transmission X-ray image generated by X-ray irradiation as the X-ray tube XA irradiates the subject M with X-rays according to the control performed by the irradiation control unit Xa. The X-ray detection signal is output as image data of a DSA image. As the two-dimensional X-ray detector XD, a flat panel type X-ray detector, an image intensifier type X-ray detector, or the like is used. In the case of the X-ray imaging apparatus of FIG. 1, the image display apparatus 1 (shown by being surrounded by a dotted line in FIG. 1) provided from the two-dimensional X-ray detector XD from the two-dimensional X-ray detector XD. A DSA image is displayed based on an X-ray detection signal as output image data.

  The image display apparatus 1 includes an image data adjustment processing unit 2 that performs an adjustment process for adjusting the X-ray detection signal as the image data output from the two-dimensional X-ray detector XD so that gradation conversion can be performed, An image data memory 3 that stores image data that has been adjusted to a state in which gradation conversion can be performed by the image data adjustment processing unit 2, and a gradation conversion unit 4 that performs gradation conversion on the image data stored in the image data memory 3 And a DSA image memory 5 for storing the DSA image acquired by the gradation processing by the gradation converting unit 4, and a display monitor 6 for displaying the acquired DSA image, an input operation menu, and the like.

  As shown in FIG. 2, the image data adjustment processing unit 2 includes a mask image signal memory 2A, a live image signal memory 2B, and an image subtraction unit 2C. In addition, the image data adjustment processing unit 2D and the adjusted data temporary A holding register 2E is provided, and image data of a difference image between the mask image and the live image is obtained. For example, when an angiographic DSA image is acquired as a difference image, a mask image before the contrast agent is input is first captured and stored in the mask image signal memory 2A, and then a live image after the contrast agent is input is captured. Are stored in the live image signal memory 2B, and after subtracting the image data of the same pixel of the mask image and the live image by the image subtraction unit 2C, an appropriate amount of base is further obtained by the signal base adjustment unit 2D. In addition to the uniform adjustment process, the adjustment process stored in the adjusted data temporary holding register 2E is repeated for each image data. In the case of angiography DSA, only the blood vessel is finally displayed in the display image.

  As a result, when the image data is stored in the adjusted data temporary holding register 2E, it is in a stage where it is adjusted for the DSA image and ready for gradation conversion, and is stored in the adjusted data temporary holding register 2E. The adjusted image data thus adjusted is sent to the image data memory 3 promptly and sequentially.

  As shown in FIG. 3, the DSA image P to be displayed is composed of N × M pixels Pa arranged in a two-dimensional matrix of vertical N rows and horizontal M columns, one for each pixel Pa. Image data corresponds. The scale of the matrix of vertical N rows and horizontal M columns varies depending on the type of detector, but examples include thousands to tens of thousands x thousands to tens of thousands.

  On the other hand, the image display device 1 includes a region-of-interest setting unit 7 that sets one or a plurality of regions of interest for a DSA image P that is a display image. That is, in the case of the region-of-interest setting unit 7, one region of interest Ra is set for the DSA image P as shown in FIG. 4 by the operation of the operation unit 8 composed of input operation devices such as a keyboard and a mouse. In addition, for example, three regions of interest Ra to Rc can be set for the DSA image P as shown in FIG.

  On the other hand, the tone conversion unit 4 performs tone conversion using the tone reference image data selected from the image data in the region of interest set by the region of interest setting unit 7 as the reference tone, and the image data of the DSA image P. To apply.

  Further, as will be described in detail below, the image display device 1 has a configuration for quickly selecting gradation reference image data corresponding to the reference gradation of the DSA image P.

  In the case of the image display device 1, first, as shown in FIG. 6, the gradation reference image corresponding to the reference gradation of the DSA image P for each of a number of division sections U set in advance for the entire DSA image P. The gradation candidate conversion unit 4 includes a reference candidate image data selection unit 9 that selects reference candidate image data as data candidates from the image data of each divided section U without reading image data from the image data memory 3. And a reference candidate image data memory 10 for registering reference candidate image data preliminarily selected by the reference candidate image data selection unit 9 in association with each divided section U.

  That is, in the case of the divided section U set for the DSA image P, as shown in FIG. 6, the divided section U is set by dividing the entire DSA image P vertically and horizontally, as shown in FIG. In addition, each divided section U includes n × m pixels Pa in a mini-matrix arrangement of n rows and m columns, and the reference candidate image data selection unit 9 performs n × for each divided section U. Reference candidate image data is selected from n × m image data corresponding to m pixels Pa.

  Specifically, the reference candidate image data selection unit 9 uses, as reference candidate image data, two image data of a maximum value (maximum pixel value) and a minimum value (minimum pixel value) from n × m pieces of image data. A selection is made for each divided section U.

  Therefore, the reference candidate image data memory 10 registers two image data of the maximum value and the minimum value for each divided section U as reference candidate image data.

  In the case of the reference candidate image data selection unit 9, specifically, the selection process of the next reference candidate image data is repeatedly performed for each divided section U.

  As shown in FIG. 8, the reference candidate image data selection unit 9 includes a maximum value holding register 9A, a minimum value holding register 9B, a maximum value selection comparison unit 9a, and a minimum value selection comparison unit 9b. The maximum value holding register 9A holds the lower limit value among the values that can be held by the register, and the minimum value holding register 9B holds the upper limit value among the values that can be held by the register.

  Then, the maximum value selection comparison unit 9a compares the size of the image data sent to the maximum value holding register 9A, and if the sent image data is larger, the maximum value holding register The 9A data is replaced with the sent image data.

  Further, the image data sent to the minimum value selection comparison unit 9b is compared with the data held in the minimum value holding register 9B. If the sent image data is smaller, the minimum value holding register The 9B data is replaced with the sent image data.

  The data held in the maximum value holding register 9A at the stage where the processing of n × m image data of one divided section U is completed is the image data of the maximum value, and the minimum value holding register 9B holds the data. The image data is the minimum image data.

  In addition, the reference candidate image data selection unit 9 uses the adjustment process performed by the image data adjustment processing unit 2 provided on the preceding stage of the gradation conversion unit 4 to select the reference candidate image data and perform image data read processing. Run without That is, in the case of the reference candidate image data selection unit 9, the image data adjustment processing unit 2 directly uses the image data at a stage where the gradation conversion can be performed by the adjustment process, thereby directly using the reference candidate image data selection unit 9. Is configured to use the adjustment processing of the image data adjustment processing unit 2. Specifically, the adjusted image data stored in the adjusted data temporary holding register 2E is sequentially sent to the reference candidate image data selection unit 9 and used for selection of the reference candidate image data. ing.

  Further, the image display device 1 divides the reference candidate image data registered in the reference candidate image data memory 10 into the divided regions corresponding to the region of interest set by the region of interest setting unit 7 among all the divided sections U of the display image. Selection candidate image data extraction unit 11 that extracts reference candidate image data of section U as selection candidate image data, and gradation reference image data is selected from selection candidate image data extracted by selection candidate image data extraction unit 11. A gradation reference image data selection unit 12 is provided.

  The selection candidate image data extraction unit 11 extracts all the reference candidate image data of the divided section U in which all or part of the region of interest is included as selection candidate image data. For example, as shown in FIG. 5, when three regions of interest Ra to Rc are set, as shown in FIG. 9, six divided sections that are all contained in the region of interest Ra as shown by hatching. U, six divided sections U that are all contained in the region of interest Rb, one divided section U that is entirely contained in the region of interest Rc, and three divided sections that contain a part The selection candidate image data extraction unit 11 selects 16 maximum image data and 16 minimum image data, which are reference candidate image data registered for a total of 16 divided sections U of the section U. Extracted as image data.

  The gradation reference image data selection unit 12 selects the maximum and minimum image data among the extracted selection candidate image data as the gradation reference image data. That is, the maximum of the 16 maximum image data and the minimum of the 16 minimum image data are selected as the gradation reference image data by the gradation reference image data selection unit 12. Is done.

  Then, the gradation conversion unit 4 performs gradation conversion on all the image data of the DSA image P using the gradation reference image data selected by the gradation reference image data selection unit 12 as a reference gradation. That is, in the case of the image display device 1, the tone conversion unit 4 performs tone conversion of the image data based on the image data having the maximum value and the minimum value in the image data of the region of interest substantially.

  In the case of the gradation converting unit 4, as shown in FIG. 11, the image data having the maximum value MX is set to the highest luminance gradation level (white density) HB, and the image data having the minimum value MU is set to the lowest luminance gradation level (black density). The image data between the maximum value MX and the minimum value MU is assigned so that the density between the maximum luminance gradation level HB and the minimum luminance gradation level LB is proportional to the data value. . Thereby, in the final image, the pixel corresponding to the image data of the maximum value MX is displayed brightest, the pixel corresponding to the image data of the minimum value MU is displayed darkest, and between the maximum value MX and the minimum value MU. As a result of displaying the pixels corresponding to the image data with a density proportional to the data value, the DSA image P is displayed on the screen of the display monitor 6 with an appropriate contrast.

  In addition to the image display device 1, the main control unit 13 appropriately uses an X-ray imaging system including an X-ray tube XA and a two-dimensional X-ray detector XD according to the input operation of the operation unit 8 and the progress of the imaging process. It plays a role in controlling the operation of the entire device by controlling it.

  Further, the number of divided sections U set for the display image is not limited to a specific number. However, if the number of divided sections U is too large, the number of reference candidate image data increases and the reference candidates are increased. The pre-selection effect of image data tends to fade. On the other hand, if the number of divided sections U is too small, the region of interest and the divided sections do not exactly correspond to each other, and there is a strong possibility that image data at a position outside the region of interest is selected as the gradation reference image data. If the display image is a medical image, the number of divided sections U is preferably about 16 × 16 to 128 × 128.

  The image display device 1 may be configured such that the number of divided sections U for the DSA image P can be changed by an input operation using the operation unit 8.

  In addition, the image display device 1 may be configured to be adjusted by the input operation of the operation unit 8 with respect to the partitioning method set for the display image.

  Next, a process of selecting gradation reference image data corresponding to the reference gradation of the DSA image P in the image display device 1 having the above-described configuration will be described with reference to the drawings. FIG. 10 is a flowchart showing a selection process of gradation reference image data corresponding to the reference gradation of the DSA image P in the image display apparatus 1.

  [Step S1] One or more regions of interest are set for the DSA image P displayed by the region-of-interest setting unit 7 in accordance with a setting operation for region-of-interest setting performed by the operator or the like by an operator or the like.

  [Step S2] The image data adjustment processing unit 2 adjusts an X-ray detection signal as image data output from the two-dimensional X-ray detector XD to prepare a state where gradation conversion can be performed.

  [Step S3] The maximum value as the reference candidate image data for each divided section U using the image data at the stage where the reference candidate image data selection unit 9 has been adjusted to a state where gradation conversion can be performed by the image data adjustment processing unit 2 And select the minimum image data.

  [Step S4] The reference candidate image data memory 10 registers two image data of the maximum value and the minimum value for each divided section U in association with each divided section U as reference candidate image data.

  [Step S5] If there are still divided sections for which selection / registration of reference candidate image data has not been completed, the process returns to step S3. If there are no divided sections for which selection / registration of reference candidate image data has not been completed, step S5 is performed. Proceed to S6.

  [Step S6] The selection candidate image data extraction unit 11 extracts all the reference candidate image data of the divided section U corresponding to the region of interest set by the region of interest setting unit 7 as selection candidate image data.

  [Step S7] The gradation reference image data selection unit 12 sets the maximum and minimum image data as gradation reference image data corresponding to the reference gradation of the DSA image P to be displayed from the extracted selection candidate image data. Is selected.

  In the case of the image display apparatus 1 according to the embodiment having the above-described configuration, when selecting the gradation reference image data corresponding to the reference gradation of the DSA image P, all images for the region of interest in the DSA image P are selected. Do not check the data one by one. That is, the reference candidate image data selected in advance for each of the plurality of divided sections U set in advance for the entire display image as candidates for gradation reference image data and registered in association with each divided section U. Of these, only the reference candidate image data of the divided section U corresponding to the region of interest is extracted as selection candidate image data and checked, and the gradation reference image data is selected. The reference candidate image data to be checked is preliminarily selected from the image data of each divided section U of the display image, and the total number of reference candidate image data to be checked is compared with the total number of image data for the region of interest. Therefore, it takes no time to read out and check the image data necessary for selecting the gradation reference image data.

  Therefore, according to the image display apparatus 1 according to the embodiment, the gradation reference image data corresponding to the reference gradation of the DSA image P can be quickly selected.

  In the case of the image display device 1, the reference candidate image data is selected and registered in the reference candidate image data memory 10 by the reference candidate image data selection unit 9 provided on the front side of the gradation conversion unit 4. Therefore, the apparatus itself can perform preliminary selection of reference candidate image data to be registered without hindering prompt selection of gradation reference image data.

  Further, in the case of the image display device 1, the reference candidate image data selection unit 9 is in a state in which the image data adjustment processing unit 2 on the front side of the gradation conversion unit 4 can perform gradation conversion on each image data of the display image. By using the adjustment process for adjusting, the selection process of the reference candidate image data without the image data reading process can be easily executed, and the reference candidate image data selection unit 9 is adjusted by the image data adjustment processing unit 2. By directly using the image data at a stage in which the gradation conversion can be performed by the method for selecting the reference candidate image data, the adjustment processing of the image data adjustment processing unit 2 can be easily used.

  In addition, in the case of the image display device 1, when a plurality of regions of interest are set for the DSA image P by the region-of-interest setting unit 7, all divided sections corresponding to the plurality of regions of interest are selected by the selection candidate image data extraction unit 11. Since the U reference candidate image data is extracted as the selection candidate image data, it is possible to select an appropriate gradation reference image data by setting an area where the gradation reference image data may exist as a region of interest without omission. Yes.

  The present invention is not limited to the above embodiment, and can be modified as follows.

  (1) In the case of the image display device 1 according to the embodiment, the gradation reference image data is the image data of the maximum value and the minimum value, but the gradation reference image data is limited to the image data of the maximum value and the minimum value. For example, the gradation reference image data may be selected based on frequency, such as mode data.

  (2) The image display apparatus 1 according to the embodiment is incorporated in the X-ray imaging apparatus and is configured to acquire image data and reference candidate image data in real time. However, the image display apparatus 1 is not included in the X-ray imaging apparatus. This is a single-type device that is not incorporated, and is based on image data that has been separately prepared in a state where gradation conversion can be performed separately by another device or reference candidate image data that has been previously preliminarily selected by another device. The image may be displayed. In the case where an image is displayed using only image data acquired at such an off-time or reference candidate image data, the image data adjustment processing unit 2 and the reference candidate image data selection unit 9 need not be provided. .

  (3) In the image display device 1 according to the embodiment, the region of interest is a square, but the region of interest is not limited to a square. The region of interest may be a shape such as a triangle, a perfect circle, or an ellipse, for example.

  (4) In the image display device 1 according to the embodiment, the divided section set for the display image is a square, but the divided section is not limited to a square. The divided section may be, for example, a triangle or a rectangle.

  (5) Although the image display device 1 of the embodiment is configured to display a medical image, an image to be displayed by the image display device of the present invention is not limited to a medical image.

It is a block diagram which shows the structure of the DSA type | formula X-ray imaging apparatus incorporating the image display apparatus which concerns on an Example. It is a block diagram which shows the structure of the image data adjustment process part of the image display apparatus of an Example. It is a schematic diagram which shows the pixel matrix of a display image with the image display apparatus of an Example. It is a schematic diagram which shows the example of a setting of the region of interest of a display image with the image display apparatus of an Example. It is a schematic diagram which shows the other example of a setting of the region of interest of a display image with the image display apparatus of an Example. It is a schematic diagram which shows the setting condition of the division division with respect to the image in the image display apparatus of an Example. It is a schematic diagram which shows the pixel matrix in the division division set to the display image with the image display apparatus of an Example. It is a block diagram which shows the structure of the reference | standard candidate image data selection part of the image display apparatus of an Example. It is a schematic diagram which shows the correspondence condition of the region of interest of a display image, and a division | segmentation division with the image display apparatus of an Example. It is a flowchart which shows the selection process of the gradation reference image data in the image display apparatus of an Example. It is a graph which shows the conversion characteristic of the gradation conversion performed to image data.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 ... Image display apparatus 2 ... Image data adjustment process part (Image data adjustment process means)
4 ... gradation conversion section (gradation conversion means)
7: Region of interest setting section (region of interest setting means)
9: Reference candidate image data selection section (reference candidate image data selection means)
10: Reference candidate image data memory (reference candidate image data registration means)
11 ... Selection candidate image data extraction unit (selection candidate image data extraction means)
12 ... gradation reference image data selection unit (gradation reference image data selection means)
P ... DSA image (image)
Ra to Rc ... Region of interest U ... Divided section

Claims (6)

  (A) Region-of-interest setting means for setting a region of interest for the display image, and (B) gradation reference image data corresponding to the reference gradation of the display image. Reference candidate image data registration means for registering reference candidate image data preliminarily selected for each divided section from among a plurality of divided section image data in association with each divided section; and (C) a reference candidate image. Among the reference candidate image data registered in the data registration means, the reference candidate image data of the divided section corresponding to the region of interest set by the region of interest setting means among all the divided sections of the display image is selected candidate image data. Selection candidate image data extracting means for extracting, and (D) gradation reference image data for selecting gradation reference image data from the selection candidate image data extracted by the selection candidate image data extracting means. Selection means, and (E) gradation conversion means for performing gradation conversion on the image data of the display image using gradation reference image data selected by the gradation reference image data selection means as a reference gradation. An image display device characterized by the above.   2. The image display device according to claim 1, wherein (F) image data is read out from the reference candidate image data to be registered in the reference candidate image data registration means for each of a plurality of preset divisions for the entire display image. An image display device comprising reference candidate image data selection means for selection without gradation before the gradation conversion means, wherein reference candidate image data selected by the reference candidate image data selection means is registered in the reference candidate image data registration means .   The image display device according to claim 2, further comprising (G) an image data adjustment processing unit that performs adjustment processing for each image data of the display image so that gradation conversion can be performed. The reference candidate image data selection means is an image display device that executes the selection process of the reference candidate image data without using the image data read process by using the adjustment process by the image data adjustment processing means.   4. The image display device according to claim 3, wherein the piggybacking on the adjustment process of the image data adjustment processing unit of the reference candidate image data selection unit is arranged so that gradation conversion can be performed by the adjustment process by the image data adjustment processing unit. Image display apparatus which is made by directly using the image data at the selected stage by the reference candidate image data selection means.   5. The image display device according to claim 1, wherein the reference candidate image data selection means preliminarily selects the maximum and minimum image data among the image data for the divided sections as reference candidate image data. An image display device in which the gradation reference image data selection means selects the maximum and minimum image data among the selection candidate image data extracted by the selection candidate image data extraction means as gradation reference image data. 6. The image display device according to claim 1, wherein the region-of-interest setting unit can set a plurality of regions of interest for one image to be displayed, and the region-of-interest setting unit can set a plurality of regions of interest. Is set, the selection candidate image data extraction unit extracts the reference candidate image data of all divided sections corresponding to a plurality of regions of interest as selection candidate image data.

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