JP5826606B2 - Image distribution server - Google Patents

Description

  The present invention relates to an image distribution server.

  Conventionally, a virtual slide image (hereinafter referred to as a VS image) obtained by photographing a pathological specimen with extremely high resolution is used in pathological diagnosis. The VS image is an image constructed by dividing and photographing a pathological specimen into small areas and arranging the acquired images of the small areas in two dimensions. Since the VS image has a very large data capacity, it is stored in an image server different from the browsing terminal. The image server distributes a part or all of the VS image to the terminal according to the position desired by the viewer and the display magnification requested for distribution from the terminal.

  As such an image server, a plurality of VS images having different resolutions are created by gradually reducing the resolution of the original image of the VS image, and a VS image having a resolution corresponding to the display magnification requested from the terminal is created. What is distributed is known (for example, refer to Patent Document 1). According to such an image server, a VS image having a relatively low resolution is distributed when displayed at a low magnification, and a VS image having a relatively high resolution is distributed when displayed at a high magnification. The terminal displays the received VS image after enlarging or reducing it so that the display magnification specified by the viewer is obtained. As described above, by distributing the VS image having the resolution corresponding to the display magnification, it is possible to shorten the time required for the transmission of data from the image server to the terminal and the enlargement / reduction of the VS image by the terminal.

JP-T-2006-519443

  However, in the case of Patent Document 1, when a viewer who is viewing a VS image displayed on a terminal requests the image server to distribute a VS image with a different display magnification, the resolution of the VS image distributed from the image server May switch. At this time, there is a disadvantage that the resolution of the VS image displayed on the terminal greatly changes with respect to the change in display magnification, which gives the viewer a sense of discomfort.

  The present invention has been made in view of the above-described circumstances, and in an image distribution server that distributes an image having a resolution according to a display magnification designated by a terminal to the terminal, the resolution naturally changes in accordance with the display magnification. An object of the present invention is to provide an image distribution server capable of distributing an image to be performed.

In order to achieve the above object, the present invention provides the following means.
The present invention is connected to an image storage server for storing a plurality of hierarchical images having different resolutions created from an original image obtained by photographing a specimen, and a terminal capable of displaying images, via a network, a resolution determination means for determining a request receiving means for receiving with the specified display magnification of the image, the required resolution based on the display magnification specified received by said request receiving means a distribution request of an image of the specimen from the The requested resolution determined by the resolution determining means is compared with the resolutions of the plurality of hierarchical images, and if there is a hierarchical image whose resolution matches the required resolution, the hierarchical image whose resolution matches the required resolution And two hierarchical images that are adjacent to the hierarchical image are acquired from the image storage server, and the resolution is the required resolution. If no matching hierarchical image is not present, an image obtaining unit for obtaining a two-layer image adjacent in between the layer corresponding to the required resolution from the image storage server, which is acquired by the image acquisition unit comprising an image synthesizing means for generating a distribution image by synthesizing bear the weight each of the two-layer image, and an image transmitting means for transmitting a distribution image generated by the image synthesizing means to said terminal, said image combining means, wherein one of the two-layer image, to provide an image delivery server subjecting greater weight to hierarchy image towards differential resolution and the required resolution is less.

  According to the present invention, when the request receiving unit receives the image distribution request together with the display magnification designation, the image obtaining unit obtains a hierarchical image corresponding to the resolution determined by the resolution determining unit based on the display magnification from the image storage server. The image composition unit generates a distribution image from the acquired hierarchical image, and the image transmission unit transmits the distribution image to the terminal. Thereby, the terminal can display an image having a resolution corresponding to the display magnification.

  In this case, the image acquisition means includes two hierarchical images including a hierarchical image having a resolution that matches the resolution determined by the resolution determination unit in the hierarchical image group, or the determined resolution sandwiched therebetween. Two hierarchical images having the closest resolution are acquired. The image composition unit synthesizes the distribution image by assigning a greater weight to the layer image having the resolution closer to the determined resolution with respect to the acquired two layer images. In other words, the synthesized image is an image in which the resolution corresponding to the display magnification requested from the terminal is simulated, so that it is possible to deliver a distribution image whose resolution naturally changes in accordance with the display magnification. it can.

In the above invention, the image synthesizing unit may transparently superimpose the two hierarchical images so that the hierarchical image with the smaller difference has a lower transparency.
By doing so, the transparency of the hierarchical image having a resolution close to the resolution determined based on the display magnification is lower than that of the other hierarchical image, and is reflected more strongly in the distribution image. As a result, the distribution images can be synthesized by simply weighting the two hierarchical images.

In the above invention, the image synthesizing unit may add a weight proportional to a difference ratio between the resolution of each hierarchical image and the required resolution to each hierarchical image.
In this way, it is possible to synthesize a delivery image in which the resolution determined based on the display magnification is more accurately realized.

The present invention also relates to an image storage means that is connected to a terminal capable of displaying an image via a network and that stores a plurality of hierarchical images having different resolutions created from an original image obtained by photographing a specimen and layered according to resolution. request receiving means and the resolution determining means for determining a required resolution based on the display magnification specified received by said request receiving means for receiving a distribution request of an image of the specimen from the terminal with the specified display magnification of the image And the required resolution determined by the resolution determining means and the resolutions of the plurality of hierarchical images stored in the image storage means, and when there is a hierarchical image whose resolution matches the required resolution the resolution select two hierarchical image composed of a hierarchical image adjacent to the layer image and the hierarchical image matching the required resolution, the resolution is pre If the hierarchical image that matches the required resolution is not present, select two hierarchical image adjacent in between the layer corresponding to the required resolution, denoted by the respective two-layer image selected weights an image synthesizing means for generating a distribution image by synthesizing, and an image transmitting means for transmitting a distribution image generated by the image synthesizing means to said terminal, said image combining means, of the two-layer image , to provide an image delivery server subjecting greater weight to hierarchy image towards differential resolution and the required resolution is less.

  Advantageous Effects of Invention According to the present invention, an image distribution server that distributes to a terminal an image having a resolution corresponding to a display magnification specified from the terminal can deliver an image whose resolution naturally changes in accordance with the display magnification. Play.

1 is a functional block diagram of an image distribution server according to an embodiment of the present invention and an overall configuration diagram of an image distribution system including the image distribution server. It is a figure which shows an example of the viewer displayed on the terminal with which the image delivery system of FIG. 1 is provided. It is a conceptual diagram explaining the hierarchical image group memorize | stored in the image storage part of the image delivery server of FIG. It is a figure which shows the modification of the image delivery server and image delivery system of FIG.

Hereinafter, an image distribution server 1 and an image distribution system 100 according to an embodiment of the present invention will be described with reference to the drawings.
As shown in FIG. 1, the image distribution system 100 according to the present embodiment is connected to a terminal 2 used by a viewer such as a pathologist and a VS image of a pathological specimen connected to the terminal 2 via the network 3. And an image distribution server 1 that stores the VS image to the terminal 2 in response to a distribution request from the terminal 2.

  The terminal 2 is installed, for example, in an examination room in a hospital where a pathologist performs pathological diagnosis. The image distribution server 1 is installed, for example, in an in-hospital laboratory or laboratory that creates a pathological specimen from a sample collected from the body of a provider such as a patient and creates a VS image of the pathological specimen. The terminal 2 and the image distribution server 1 may be installed in the same facility and connected via a local network (network 3) such as an intranet, or installed in different facilities and connected to a wide area network such as the Internet or a telephone line. It may be connected via (network 3).

  The terminal 2 is a computer including a screen, a main storage device, a CPU (Central Processing Unit) that reads and executes a program stored in the main storage device, and an input device such as a mouse and a keyboard. The main storage device stores a viewer program for displaying a viewer window 4 (hereinafter referred to as a viewer 4) in which an image display area for displaying a VS image and a user interface area operated by a viewer are set. ing. When the viewer gives an instruction to start the viewer program using the input device, the CPU executes the viewer program, and the viewer 4 is displayed on the screen.

  FIG. 2 is a diagram illustrating an example of the viewer 4. The user interface area B includes a specimen ID column C in which a specimen ID indicating a specimen of a VS image that the viewer wants to browse is input, and slide bars D1 to D3 for selecting a color tone such as brightness and contrast of the VS image and a display magnification. And at least a thumbnail column E for displaying a thumbnail Q of a VS image already acquired from the image distribution server 1 and stored as a cache image (described later).

  As will be described in detail later, the terminal 2 uses the sample ID, position, and display magnification (hereinafter, requested sample ID, requested position) of the VS image that the viewer wants to browse based on an operation performed on the user interface area B by the operator. And distribution request information including at least the request display magnification) and transmitting the distribution request information to the image distribution server 1.

  The image distribution server 1 stores an image storage unit 11 that stores a VS image created by the VS image creation device 5 and a hierarchical image group in which the resolution is gradually reduced from the VS image stored in the image storage unit 11. The hierarchization processing unit 12 to be created, the request receiving unit (request receiving means) 13 for receiving the distribution request information from the terminal 2, and two layers from the hierarchical image group according to the distribution request information received by the request receiving unit 13 A resolution determining unit (resolution determining unit) 14 for selecting a hierarchical image, an image processing unit (image combining unit) 15 for generating a distribution image from the two hierarchical images selected by the resolution determining unit 14, and the image processing unit 15 includes an image transmission unit (image transmission unit) 16 that transmits the distribution image generated by 15 to the terminal 2.

  The image storage unit 11 stores an original image of a VS image, which is a digital image of a pathological specimen imaged with extremely high resolution by the VS image creation device 5, in association with the specimen ID assigned to each pathological specimen. Specifically, the pathological specimen and the barcode on which the specimen ID indicating the pathological specimen is recorded are attached to the same slide glass, and the VS image creation device 5 continuously images the pathological specimen and the barcode, The sample ID is associated with the original image of the VS image and stored in the image storage unit 11.

  At this time, the VS image creation device 5 divides the pathological specimen into small regions and captures images by repeatedly imaging the pathological specimen using a relatively high magnification objective lens while moving the pathological specimen by small amounts. The captured image of the small area (hereinafter referred to as a tile image) is given an address indicating a position in the pathological specimen, and a part or all of the VS image is arranged by arranging some or all of the tile images according to the address. Is built.

  The hierarchization processing unit 12 reads the original image from the image storage unit 11 when the original image of the newly created VS image is stored in the image storage unit 11, and reduces the resolution of the original image stepwise. Thus, a hierarchical image group having resolutions of 1/1, 1/2, 1/4, 1/8,... With respect to the original image is created. Specifically, binning is performed with 1 pixel × 1 pixel, 2 pixels × 2 pixels, 4 pixels × 4 pixels, 8 pixels × 8 pixels,... Adjacent to each other in each tile image in the vertical direction and the horizontal direction as one pixel.

  As shown in FIG. 3, the hierarchical image group created in this way forms a pyramid-like hierarchical structure that is hierarchized according to the resolution and the resolution becomes smaller as it is higher. Hereinafter, for the sake of brevity, a hierarchical image having a resolution of 1 / n (n = 1, 2, 4, 8,. The hierarchization processing unit 12 stores the created hierarchical image group in the image storage unit 11 in association with the sample ID. As a result, the image storage unit 11 stores the original image and the hierarchical image group for each pathological specimen.

  The request receiving unit 13 outputs the requested display magnification of the information included in the distribution request information received from the terminal 2 to the resolution determining unit 14, and outputs the requested sample ID and the requested position to the image processing unit 15.

  The resolution determining unit 14 determines the resolution corresponding to the requested display magnification from the requested display magnification received from the request receiving unit 13. The required display magnification and the resolution have a proportional relationship in which the resolution increases as the required display magnification increases, and is stored in the resolution determination unit 14 as data associated in advance. The resolution determination unit 14 outputs the determined resolution (hereinafter referred to as a required resolution) to the image processing unit 15.

  First, the image processing unit 15 acquires two hierarchical images from the image storage unit 11 based on the requested sample ID input from the request receiving unit 13 and the requested resolution input from the resolution determining unit 14.

  Specifically, the image processing unit 15 compares the determined resolution with the resolution of each hierarchical image constituting the hierarchical image group. If there is a hierarchical image having a resolution that matches the required resolution, the hierarchical image and a hierarchical image positioned immediately above or directly below the hierarchical image are selected. On the other hand, when there is no hierarchical image having a resolution that matches the required resolution, hierarchical images that are positioned immediately above and below the hierarchy are selected with a hierarchy corresponding to the required resolution in the hierarchical structure. Then, two hierarchical images selected from the hierarchical image group associated with the requested specimen ID are acquired from the image storage unit 11. Here, the image processing unit 15 selects and reads out some or all tile images according to the requested position and the requested display magnification.

  Next, the image processing unit 15 performs image processing on the acquired two hierarchical images, and then generates a distribution image from these hierarchical images. Specifically, the image processing unit 15 includes a plurality of types of image processing filters, and applies various image processing filters to the two hierarchical images acquired from the image storage unit 11 in a previous stage and a subsequent stage. To do. First, in the previous step, the image processing unit 15 applies a color correction filter that corrects brightness, contrast, and the like to the two hierarchical images. The setting of the color tone correction filter is determined by the color tone slide bars D1 and D2 provided in the user interface area B of the viewer 4.

  Subsequently, in a later stage, the image processing unit 15 applies a transparency filter for correcting the transparency of the image to the two hierarchical images. Here, the image processing unit 15 is configured so that the ratio of the transparency of the two hierarchical images is the reciprocal of the ratio of the difference between the resolution of each hierarchical image and the required resolution determined by the resolution determining unit 14. Transparency of each hierarchical image is determined so that the sum of 1 becomes 1. When the transparency is 1, the hierarchical image is completely transparent, and when the transparency is 0, the hierarchical image is completely opaque.

  For example, when the resolution of the original image is R and the required resolution is R / 3, the resolution determination unit 14 selects a 1/2 image and a 1/4 image. The difference between the required resolution R / 3 and the resolution R / 2 of the immediately higher layer image is R / 6, and the difference between the required resolution R / 3 and the resolution R / 4 of the immediately lower layer image is R / 12. These ratios are 2: 1. Accordingly, the transparency of the 1/2 image is determined to be about 0.33, and the transparency of the 1/4 image is determined to be about 0.67. By doing in this way, a large weight is given to the hierarchical image having a resolution close to the required resolution.

  In this way, after applying various image processing filters to the two hierarchical images in the previous stage and the subsequent stage, the image processing unit 15 generates a distribution image by superimposing these hierarchical images. As a result, when a hierarchical image having a resolution that matches the requested resolution exists in the image storage unit 11, the transparency of the hierarchical image becomes 0, and a distribution image reflecting only the hierarchical image is generated. On the other hand, when there is no hierarchical image having a resolution that matches the required resolution in the image storage unit 11, a distribution image having a pseudo required resolution is generated from two hierarchical images having a resolution close to the required resolution.

  In the case of the above-described example, the 1/2 image is reflected more strongly than the 1/4 image, and the relatively detailed structure in the 1/2 image is also displayed relatively clearly. A distribution image having an equivalent resolution is generated. The image processing unit 15 outputs the generated distribution image to the image transmission unit 16, and the image transmission unit 16 transmits the distribution image to the terminal 2 that has transmitted the distribution request information.

Next, the operation of the image distribution system 100 including the image distribution server 1 configured as described above will be described.
In order to perform pathological diagnosis of a pathological specimen using the image distribution system 100 according to the present embodiment, the viewer first activates the viewer 4 in the terminal 2 and sets the specimen ID of the specimen to be diagnosed in the specimen ID column C. Click on the Enter button F. As a result, the terminal 2 creates distribution request information and transmits it to the image distribution server 1.

  At this time, when a sample ID is newly input, the terminal 2 creates distribution request information with the requested display magnification as the lowest magnification and the requested position as the center position. As a result, the terminal 2 receives the distribution image, which is the low-magnification and low-resolution VS image P on which the entire image of the pathological specimen to be diagnosed is displayed, and displays it on the viewer 4.

  The terminal 2 stores the VS image P received from the image distribution server 1 as a cache image in a cache memory provided in the CPU. When the VS image having the same request position and request display magnification as the cache image existing in the cache memory is designated again, the terminal 2 reads the cache image without newly requesting distribution from the image distribution server 1 to display the image display area. A is displayed. Also, the terminal 2 creates a thumbnail Q of the cache image and displays it in the thumbnail list E. The viewer can also redisplay the cache image in the image display area A by designating the thumbnail Q displayed in the thumbnail list E by the input means.

  The viewer, after observing the whole image of the pathological specimen displayed on the terminal 2, for example, designates a suspicious position of the lesion in the whole image with the mouse, and sets the display magnification to a higher value by the slide bar D3. Then, click the confirmation button F. As a result, the terminal 2 requests the image distribution server 1 for distribution of the VS image in which the designated position is enlarged, acquires the VS image, and displays it in the image display area A. In this way, the viewer can observe the desired position of the pathological specimen at the desired display magnification by repeatedly specifying the position and the display magnification.

  In this case, according to the present embodiment, the image distribution server 1 distributes to the terminal 2 a distribution image having a resolution that matches or is approximately the same as the requested resolution proportional to the requested display magnification from the terminal 2. That is, when the VS image P displayed on the terminal 2 is enlarged / reduced, the resolution continuously increases / decreases in proportion to the enlargement / reduction ratio. Thereby, the resolution of the VS image P displayed on the terminal can be naturally changed with the change of the display magnification.

  Also, by creating a large number of hierarchical images with a small resolution width, it is possible to deliver a VS image whose resolution naturally changes in accordance with the display magnification to the terminal as in the present embodiment. However, in that case, since the data capacity of each hierarchical image is extremely large, the image storage unit 11 is required to have a huge storage capacity. On the other hand, according to the present embodiment, the number of hierarchical images is limited, for example, several for one pathological specimen, and it is not necessary to enlarge the image storage unit 11.

  For the VS image P displayed on the terminal 2 as described above, the viewer moves the color slide bars D1 and D2 to the left and right to set the desired setting values, and clicks the confirm button F. Thus, the color tone such as the brightness and contrast of the VS image P can be changed. The terminal 2 transmits to the image distribution server 1 color tone change request information including the installation value set by the slide bars D1 and D2. The image distribution server 1 resets the corresponding image processing filter of the image processing unit 15 according to the received color tone change request information, and then creates and transmits a distribution image again based on the distribution request information received immediately before. As a result, the VS image P whose color tone has been changed is displayed on the terminal 2.

  Here, when the image distribution server 1 receives the color tone change request information from the terminal 2, the image distribution server 1 instructs the terminal 2 to delete all the cache images stored so far. Note that the terminal 2 may be configured such that the CPU executes erasure of all cache images at the same time when the color tone change requesting unit is transmitted to the image distribution server 1.

  If the terminal 2 continues to hold the cache image even after the color tone setting is changed, the following inconvenience occurs. That is, the cache image existing in the terminal 2 remains in the color tone before the change even after the setting of the color correction filter of the image processing unit 15 is changed. That is, the VS image received from the image distribution server 1 after the color tone change and the VS image received from the image distribution server 1 before the color tone change are displayed on the terminal 2 with different color tone settings. For the viewer, the appearance of the VS image that does not reflect the change once set often appears in the middle of the diagnosis, which also hinders troublesome and smooth diagnosis. Therefore, by deleting all the cache images held by the terminal 2 every time the color tone setting is changed, only the VS image reflecting the new setting is displayed after the color tone setting is changed. Such inconveniences can be solved.

In the present embodiment, the image distribution server 1 distributes the distribution image to the terminal 2 in tile image units, and the terminal 2 displays the tile image in the viewer 4 as the VS image P by arranging the tile images in two dimensions. The terminal 2 may display the image on the viewer 4 after performing the smoothing process on the edge portion where the tile images are adjacent to each other.
By doing in this way, the joint of the tile image which feels bothersome for the viewer or obstructs the observation becomes inconspicuous, and the VS image P can be observed more comfortably.

  Further, in the present embodiment, the image processing unit 15 weights each hierarchical image in the distribution image by performing transparency processing on two hierarchical images having different resolutions. The image weighting method is not limited to this.

In the present embodiment, the image distribution server 1 may distribute a distribution image having a size larger than the image display area A to the terminal 2.
In this way, for example, when a region slightly deviated from the region currently displayed in the image display region A is viewed, the cache image can be displayed in a short time, and the VS image can be efficiently displayed. P can be browsed.

  Further, in the present embodiment, the image distribution server 1 stores the hierarchical image group, but instead, an image storage server separate from the image distribution server 1 stores the hierarchical image group and distributes it. The image distribution server 1 may acquire a hierarchical image from the image storage server based on the request information.

  In this case, as shown in FIG. 4, the image distribution server 1 distributes the distribution image from the image storage server 20 based on the distribution request information received by the request reception unit 13 and the resolution determined by the resolution determination unit 14. The image acquisition part (image acquisition means) 17 which acquires two hierarchy images used for the production | generation of is provided. The image processing unit 15 performs the above-described image processing on the two hierarchical images acquired by the image acquisition unit 17, and then generates a distribution image from these hierarchical images.

DESCRIPTION OF SYMBOLS 1 Image distribution server 2 Terminal 3 Network 4 Viewer window 5 Virtual slide image creation apparatus 11 Image storage part (image storage means)
12 Hierarchical processing unit 13 Request receiving unit (request receiving means)
14 Resolution determination unit (resolution determination means)
15 Image processing unit (image composition means)
16 Image transmission unit (image transmission means)
17 Image acquisition unit (image acquisition means)
20 Image storage server 100 Image distribution system A Image display area B User interface area C Sample ID field D1-D3 Slide bar E Thumbnail field F Confirm button P VS image (distributed image)
Q Thumbnail

Claims (4)

An image storage server for storing a plurality of hierarchical images with different resolutions created from the original image from which the specimen is photographed and layered according to the resolution and a terminal capable of displaying the images are connected via a network,
Request receiving means for receiving a distribution request for the image of the specimen from the terminal together with designation of a display magnification of the image;
A resolution determination means for determining a required resolution based on the display magnification specified received by said request receiving means,
The requested resolution determined by the resolution determining means is compared with the resolutions of the plurality of hierarchical images, and when there is a hierarchical image whose resolution matches the required resolution, the hierarchical level that matches the required resolution. If two hierarchical images consisting of an image and a hierarchical image adjacent to the hierarchical image are acquired from the image storage server and there is no hierarchical image whose resolution matches the required resolution, the hierarchical level corresponding to the required resolution Image acquisition means for acquiring two hierarchical images adjacent to each other with the image storage server therebetween ,
An image synthesizing means for generating a distribution image by synthesizing bear the weight each of the two-layer image acquired by the image acquiring means,
And an image transmitting means for transmitting a distribution image generated by the image synthesizing means to said terminal,
The image synthesizing means, wherein two of the hierarchical image, the image distribution server subjecting greater weight to hierarchy image towards differential resolution and the required resolution is less.   The image distribution server according to claim 1, wherein the image synthesizing unit transparentizes and superimposes the two layer images so that the layer image having the smaller difference has a lower transparency. The image distribution server according to claim 1, wherein the image composition unit assigns a weight proportional to a ratio of a difference between a resolution of each hierarchical image and the required resolution to each hierarchical image. Connected to a device capable of displaying images via a network,
Image storage means for storing a plurality of hierarchical images having different resolutions created from an original image in which a specimen is photographed and layered according to resolution;
Request receiving means for receiving a distribution request for the image of the specimen from the terminal together with designation of a display magnification of the image;
A resolution determination means for determining a required resolution based on the display magnification specified received by said request receiving means,
The requested resolution determined by the resolution determining means is compared with the resolution of the plurality of hierarchical images stored in the image storage means, and when there is a hierarchical image whose resolution matches the required resolution, When two hierarchical images composed of a hierarchical image whose resolution matches the required resolution and a hierarchical image adjacent to the hierarchical image are selected, and there is no hierarchical image whose resolution matches the required resolution , the required resolution An image synthesizing unit that generates two distribution images by selecting two layer images adjacent to each other with a layer corresponding to the selected layer image and combining the selected two layer images with weights;
And an image transmitting means for transmitting a distribution image generated by the image synthesizing means to said terminal,
The image synthesizing means, wherein two of the hierarchical image, the image distribution server subjecting greater weight to hierarchy image towards differential resolution and the required resolution is less.

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