JP2000270325A - File communication server - Google Patents

Abstract

(57) [Summary] [PROBLEMS] To enable file communication between systems that can handle different file formats. For example, when a JPEG image file is communicated between systems 1A, 1B, and 1C, a transmitting system 1
The image file is sent from A to the server 3, stored in the server 3, and sent from the server 3 to the receiving side systems 1B, 1C. When receiving the image file from the transmitting system 1A, the server 3 permits the JPEG compression format desired by the transmitting system 1A, and permits the JPEG compression format desired by the transmitting system 1A. It receives the compressed image file 21, 23 or 25 and saves it in an appropriate JPEG compression format. Server 3
When transmitting the stored image files 51, 53 or 55 to the receiving side systems 1B and 1C, the image files are transmitted in a JPEG compression format that can be handled by the receiving side systems 1B and 1C.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a server for communicating files between systems, and more particularly, to a server suitable for communicating image files in conformity with DICOM 3.0, which is an international standard for medical images. Related to a file communication server.

[0002]

2. Description of the Related Art DICO, an international standard for medical images
M3.0 defines a protocol for communicating an image file, a format of the image file, and the like. inside that,
It is defined that JPEG can be used as a compression method. Therefore, in DICOM, uncompressed files and JP
A total of 10 or more types of image files can be used together with the EG compressed file. For example, image files in the following formats can be used.

(1) Non-compressed Implicit 8bit, Implicit 12bit, Implicit 16bit Explicit 8bit, Explicit 12bit, Explicit 16bit (2) Lossless compression Lossless 8bit, Lossless 12bit, Lossless 16bit (3) Lossless compression Baseline 8bit, Extended 8bit, Extended Systems that communicate medical images in compliance with 12-bit DICOM inform one another of which file format is being handled, negotiate a common file format, and then start communication of the common format image file.

[0004]

[0006] Image files cannot be communicated between systems that do not have a common image file format.

Accordingly, it is an object of the present invention to enable files to be communicated between systems that handle different file formats.

Another object of the present invention is to provide a file transfer method which is advantageous in achieving the above object.

[0007]

SUMMARY OF THE INVENTION The present invention provides a file communication system for receiving and storing a file from a transmitting system that wants to transmit a file, and transmitting the stored file to a receiving system that wants to receive the file. A server and a method of operating the server are provided.

[0008] The file communication server of the present invention negotiates a receiving format when receiving a file from the transmitting system with the transmitting system, and then receives the file in the receiving format from the transmitting system; A transmission unit that negotiates the transmission format when transmitting a file to the receiving system with the receiving system and then transmits the file to the receiving system, and a storage format for storing the file when receiving the file. Decide,
When saving a received file in the save format and transmitting the saved file, determine the actual transmission format for sending the file, convert the file to the actual transmission format described above, and pass the file format to the transmission unit Unit. Here, the storage format is the same as the reception format or a file format that can be converted from the reception format. The actual transmission format is the same as the storage format or a file format that can be converted from the storage format and can be handled by the receiving system.

Since this file communication server has a file format conversion function, even if the transmitting system and the receiving system do not have a common file format,
The file can be communicated using the file communication server as an intermediary.

In a preferred embodiment, when the receiving unit negotiates the receiving format with the transmitting system, the receiving unit uses a file format that can be handled by the transmitting system as the receiving format.
Therefore, negotiation of the reception format with the transmission side system is always established, and the file can be reliably received from the transmission side system.

In a preferred embodiment, when the transmission unit negotiates the transmission format with the receiving system, a file format that can be handled by the receiving system is set as the transmission format.
Therefore, negotiation of the transmission format with the receiving system is always established, and the file can be transmitted to the receiving system without fail.

In a preferred embodiment, the file communication server stores a preset setting storage format. When determining the storage format, if the setting storage format is the same as the reception format or can be converted from the reception format, the file conversion unit of the server uses the setting storage format as the storage format. If the storage format cannot be converted from the reception format, another file format that can be converted from the reception format is set as the storage format. As a result, when saving the received file, in principle, it is possible to save in a desired file format set in advance, and even if the setting saving format is inappropriate, it is possible to surely save the received file in another appropriate format. it can.

In a preferred embodiment, the file conversion unit includes:
When the storage format is determined, even if the setting storage format can be converted from the reception format, it is disadvantageous from a predetermined viewpoint to convert from the reception format to the setting storage format (for example, a disadvantage that the file size increases). In this case, another file format that can be converted from the reception format and is more advantageous than the setting storage format (for example, does not increase the file size) is set as the storage format. As a result, the data is stored in the setting storage format in principle, but if there is a more advantageous storage format, the data can be stored in the more advantageous storage format.

In a preferred embodiment, when the file format conversion unit determines the actual transmission format, if the transmission format negotiated with the receiving system is the same as the storage format or can be converted from the storage format, the file format conversion unit determines the actual transmission format. The negotiated transmission format is set as the actual transmission format. On the other hand, if the negotiated transmission format cannot be converted from the storage format, another file format that can be converted from the storage format and can be handled by the receiving system is used as the actual transmission format. Format. This allows files stored in any format,
The data can be transmitted to the receiving system in a format that can be reliably handled by the receiving system.

In a preferred embodiment, the principle of the present invention is applied to image file communication conforming to DICOM, and the above-mentioned file format is specifically a JPEG compression format (including non-compression) of an image file. However, the field of application of the present invention is not limited to image files and their compression formats, but is also applicable to other files and other file formats.

In a preferred embodiment, when the compression format of an image file is converted (for example, compression or decompression is performed), the image file is separated into a header and data, and only the data is converted. The converted data is created by combining the converted data with the subsequent data. Thus, when referring to a header including image information such as the file name, the presence / absence of compression, and the file format, compression / decompression processing is not necessary, which is advantageous in handling various compression formats.

The server of the present invention can be typically implemented by a computer, and a computer program for that can be installed or loaded on the computer through various media such as a disk storage, a semiconductor memory, and a communication network. it can.

[0018]

FIG. 1 shows an overall configuration of an embodiment in which the present invention is applied to communication of medical images conforming to DICOM.

A plurality of client systems (hereinafter simply referred to as clients) 1A, 1B,
1C,... And a server system (hereinafter simply referred to as a server) 3 for mediating delivery of medical images between the clients (or storing various medical images and providing the clients with desired images). Exists. Each of the clients 1A, 1B, 1C,... Is communicably connected to the server 3 through a communication network (not shown) at any time or all the time.

The server 3 includes a receiving unit 13 and a JPEG unit 15
And a transmission unit 19. The receiving unit 13 and the transmitting unit 19 are configured such that the server 3 receives an image file from the client 1A, 1B, 1C,.
When sending image files to 1B, 1C,.
It executes a communication protocol according to the OM. In DICOM, the format of an image file to be communicated is some JPEG compression format (in this specification, the term “JPEG compression format” means not only a JPEG compressed file format but also an uncompressed file format. Used in). The JPEG unit 15 stores the image file received by the receiving unit 13 from the clients 1A, 1B, 1C,... In a JPEG compression format suitable for storage,
Further, the transmitting unit 19 transmits the saved file to the client 1A,
When the data is transmitted to 1B, 1C,..., The stored file is transmitted to the transmission unit 19 in a JPEG compression format suitable for transmission.

As already described in the section of the prior art, the DIC
Systems that communicate image files according to OM
Before starting transmission / reception of an image file, one system notifies the other system of a JPEG compression format that can be handled, and a common file format is negotiated between the two systems. In this negotiation, the receiving unit 13 and the transmitting unit 19 of the server 3 determine that the client 1A, 1B, 1 can handle all JPEG compression formats.
Notify C, ... Therefore, the clients 1A, 1
No matter how limited the JPEG compression format that can be handled by B, 1C,...
., B, 1C,... Can always be established. Therefore, the format of the image file that the server 3 receives from the clients 1A, 1B, 1C,... And the image file that is transmitted to the clients 1A, 1B, 1C,. As described in the section of the prior art, JPE
The G compression format includes, for example, the following.

(1) Non-compressed Implicit 8bit, Implicit 12bit, Implicit 16bit Explicit 8bit, Explicit 12bit, Explicit 16bit (2) Lossless compression Lossless 8bit, Lossless 12bit, Lossless 16bit (3) Lossless compression Baseline 8bit, Extended 8bit, Extended The JPEG unit 15 of the 12-bit server 3 saves the received image file in a storage device in the server 3 in a certain format,
Upon receiving a request from the client, the requested image file is read from the storage device, the format is converted as necessary, and then the image file is transmitted to the client. (Hereinafter, the JPEG compression format of a received image file is called a “reception format,” and the JPEG format used when saving
The compression format is called a “storage format”, and the JPEG compression format used when transmitting the compression format is called a “transmission format”. )
The JPEG unit 15 has an environment file 17 in which a storage format and a transmission format are each set to a specific format in advance. In this environment file 17, the storage format is one in principle, but a plurality of transmission formats can be set for each client. Upon receiving the image file, the JPEG unit 15 stores the received image file in a storage device in a storage format set in the environment file 17 in principle. When a request for an image file is received from a client, the JPEG unit 15 notifies the client of the transmission format set for the client in the environment file 17 and causes the client to specify a desired format from the transmission format. Then, the stored image file is transmitted to the client in a transmission format specified by the client in principle.

However, depending on the relationship between the reception format and the storage format, it may not be advantageous or possible to convert the reception format to the storage format set in the environment file 17. Similarly, in the relationship between the storage format and the transmission format,
It may not be advantageous or possible to convert the storage format to the transmission format specified by the client. In such a case, as described later, the JPEG unit 15 selects an appropriate storage format different from the storage format set in the environment file 17, or selects an appropriate transmission format different from the transmission format specified by the client. select. Since the JPEG unit 15 has this flexible format selection function, the server 3
Functions as an intermediary between clients of different file formats that can be handled so that image files can be communicated between the two clients without any problem.

The operation of this embodiment is as follows. The JPEG compression format can be divided into 1 as described above.
Although there are zero or more types, in order to avoid unnecessarily complicating the description, the JPEG compression format will be roughly classified into three formats: non-compression, lossless compression, and lossy compression.

As shown in FIG. 1, when the client 1A wants to send an image file to the server 3, first, between the client 1A and the server 3, the file format (the uncompressed file 21 , Losslessly compressed file 23 or lossyly compressed file 25) (arrows 31, 32,
35). At this time, the receiving unit 13 of the server 3 accepts any file format specified by the client 1A, so that the negotiation is established. Thereafter, the client 1A transmits the image files 21, 23, 25 to the server 3 (arrows 41, 43, 45). The JPEG unit 13 of the server 3 determines the reception format of the image files 21, 23, 25 received from the client 1A and the environment file 1
7, the storage format for the image files 21, 23, 25 is determined based on the storage format set in
Then, the image file is converted from the reception format to the determined storage format (of course, if the reception format and the storage format are the same, no conversion is performed), and the files are stored in the storage device, for example, as the files 51 and 5.
Save as 3,55.

The clients 1B and 1C are connected to the server 3
When the user wants to transmit a certain image file from the client, first, negotiations regarding the transmission format of the image file are performed between the clients 1B and 1C and the server 3 (arrows 71 and 73). At this time, the transmitting unit 19 of the server 3 notifies the clients 1B and 1C that the client 1B and 1C can handle any of one or two or more transmission formats preset for the clients 1B and 1C. , 1C can designate a desired format from the transmission formats for itself to the server 3. Thereafter, the image file is transmitted from the server 3 to the clients 1B and 1C (arrows 81 and 83). At this time, the JPEG unit 15 of the server 3 determines the optimal transmission format from the storage format of the image file and the transmission format specified by the clients 1B and 1C, and stores the image file in the transmission format in the client 1B, 1C. Send to For example, if the transmission format specified by the client 1B is the same as the storage format of the image file to be transmitted, the server 3 transmits the image file in the same format as the storage format (arrow 8).
1). On the other hand, if the transmission format specified by the client 1C is different from the storage format, the server 3 converts the image file in the storage format into a storage format specified by the client or an image in another appropriate transmission format (if it is inappropriate). The file is converted into a file 61, and the converted image file 61 is transmitted (arrow 83).

FIG. 2 shows a communication procedure when an image file is transmitted from the client 1 to the server 3.

First, the client 1 specifies a JPEG compression format (reception format) of an image file to be transmitted, and
An association establishment request is issued to the server 3 (step S1). The server 3 returns an association acknowledgment to the client 1 irrespective of the reception format specified by the client (S
2). Next, the client 1 issues a save request to the server 3 (S3). The server 3 returns a save response to the client 1 (S4). Upon receiving the storage response, the client 1 converts the image file to be transmitted into a DICOM object in the reception format permitted by the server 3 (that is, the reception format specified first by the client 3), and transmits the DICOM object to the server 3 (S5). The server 3 registers the image-related information of the received image file in a database in the server 3 (S6). Further, the server 3 acquires the storage format set in the environment file 17, determines the actual storage format from the set storage format and the format of the received image file, and converts the received image file into that format. The data is stored in the determined storage format (S7). After saving the image file,
The server 3 returns an image file reception response to the client 1 (S8). Then, the client 1 issues an association release request to the server 3 (S9). In response, the server 3 returns an association release response to the client 1 (S10).

FIG. 3 shows the logic for determining the storage format when the server 3 saves the image file received from the client 1 in step S7.

As shown in FIG. 3, the reception formats are roughly classified into three types: “non-compression”, “lossless compression” and “lossy compression”. On the other hand, the storage format (setting There are four types of “storage format”: “non-compression”, “lossless compression”, and “lossy compression” and “save in reception format”. Actually, as described above, non-compression, lossless compression, and lossy compression are each further divided into finer formats.
Although there are more than three formats, the description is omitted here. In FIG. 3, a mark “○” means that the data is stored according to the setting storage format.

As shown in FIG. 3, when the setting storage format is "uncompressed", the received image file is converted to the uncompressed format (that is, if the received format is uncompressed), regardless of the reception format. If the receiving format is compressed, it is uncompressed and saved (as is). When the setting storage format is “save in reception format”, the data is stored in the reception format without compression or expansion. When the setting storage format is “lossless compression”, if the reception format is uncompressed, it is losslessly compressed and saved, and if the reception format is lossless compression, it is saved as it is. However, even if the setting storage format is “lossless compression”, if the reception format is lossy compression, the data is stored in the lossy compression format. The reason is that even if an image that has been lossy-compressed is converted to lossless compression, the file size will increase with the loss of image quality due to lossy compression. This is because it is small and advantageous. When the setting storage format is "irreversible compression", the data is saved with lossy compression in principle, however, when the receiving format cannot be converted to the lossy compression format of the setting storage format (for example, when the receiving format is set to Implicit 16bit) In the case where the storage format is Baseline, for example), the data is stored in the reception format as shown in parentheses in FIG.

With the above-described storage format determination logic, no matter what image format of the received image file is received from the client, it is ensured that the image quality is substantially the same as when the image file is stored in the set storage format. Can be saved.

FIG. 4 shows a communication procedure when an image file is transmitted from the server 3 to the client 1.

First, the client 1 issues an association establishment request to the server 3 (step S2).
1). The server 3 returns an association acceptance response to the client 1 (S22). Next, client 1
A transfer request is issued to the server 3 by designating desired image information (S23). The server 3 is convinced that the image information requested to be transferred is registered in the database (S2
4) Then, an initial transfer response is issued to the client 1 (S25).

Subsequently, the server 3 acquires one or more transmission formats for the client 1 from the environment file 17 and specifies this transmission format to establish a separate association with the client 1. Make a request (S2
6). The client 1 permits one desired transmission format from among the transmission formats specified by the server 1, and returns an association acceptance response specifying the permitted transmission format to the server 3 (S27). Server 3 is Client 1
Is issued to the server (S28). Client 1
The storage response is returned to the server 3 (S29). The server 3 reads the requested image file from the storage location,
This is sent in DICOM in the transmission format permitted by client 1.
Is converted into an object and transmitted to the client 1 (S
30). The client 1 receives the transmitted image file and returns a reception response to the server 3 (S3).
1). The server 3 sends a transfer response as progress information to the client 1 (S32). The server 3 issues an association release request to the client 1 (S
33). The client 1 issues an association release response to the server 3 (S34).

The operations in steps S26 to S34 described above are repeated for the number of transmission formats requested by the client 1. When the process is completed, the server 3 issues a transfer response indicating the end to the client 1 (S35). The client 1 issues an association release request to the server 3 (S36). The server 3 returns an association release response to the client 1 (S37).

FIG. 5 shows the server 3 in step S30 described above.
2 shows the logic for determining the transmission format when the image file is transmitted to the client 1.

As shown in FIG. 5, the storage format in the server 3 is roughly classified into three types: "non-compression", "lossless compression" and "lossy compression". Storage format), there are three types of “non-compression”, “lossless compression” and “lossy compression”. Actually, as described above, non-compression, lossless compression, and irreversible compression are each further divided into finer types, and there are ten or more types, but the description is omitted here. In FIG. 5, the symbol “○” means that the data is transmitted in the designated transmission format.

As shown in FIG. 5, when the designated transmission format is “uncompressed”, the saved image file is converted to the uncompressed format (that is, the storage format is uncompressed), regardless of the storage format. If it is, then send it as is, and if the storage format is compressed, expand it to uncompressed). When the designated transmission format is “lossless compression”, if the storage format is uncompressed, the data is converted to a lossless compression format and transmitted. If the storage format is lossless compression, the lossless compression format is transmitted. However, even if the designated transmission format is “lossless compression”, if the storage format is irreversible compression, the data is decompressed to the non-compression format and transmitted. The reason is that even if an image that has been lossy compressed is converted to lossless compression and transmitted,
This is because irreversible compression is accompanied by deterioration of image quality, so that it is more advantageous to send the image in non-compression rather than to save the trouble of lossless compression. If the specified transmission format is “irreversible compression”, the data will be transmitted using irreversible compression in principle. However, if the storage format cannot be converted to the specified transmission format irreversible compression format (for example, if the reception format is Implicit 16bit, In the case where the setting storage format is Baseline, for example), the data is transmitted in an uncompressed format as shown in parentheses in FIG. The reason for using the non-compressed format in this last case is that any client can be handled without any restrictions as long as the client is in the non-compressed format.

According to the above-described transmission format determination logic, the image quality of any storage format can be maintained at substantially the same image quality as when the image file is transmitted in the transmission format specified by the client, and This can be transmitted to the client in a format that can be reliably handled by the client.

FIG. 6 shows that the server 3 and the client 1
A method for compressing / decompressing a COM-compliant medical image file will be described.

The image file 101 includes a header 103 and data 105. The header 103 includes patient information and image information, and also describes whether JPEG compression is performed, a compression format, a file name, and the like. The data 105 is data of a net image value. When the image file 101 is JPEG-compressed / decompressed, the header 103 and the data 105 are separated, and only the data 105 is subjected to JPEG conversion processing such as JPEG compression / decompression. After that, the original header 103 and the data 111 after the JPEG conversion are combined to form the converted image file 12.
Create 1.

As described above, the JPEG conversion process is performed only on the data of the image file, so that the image information such as the file name and the file format and the patient report are read by the JPEG when reading the JPEG by referring to the header. Since there is no need to perform processing, it is easy to handle various JPEG compression format files. Also, since the size of the header is much smaller than that of the data, the compression of only the data can achieve a size reduction substantially equivalent to the compression of the entire file.

The embodiment of the present invention has been described above.
The above embodiment is merely an example for describing the present invention, and is not intended to limit the present invention to only the above embodiment. Therefore, the present invention can be implemented in various forms other than the above-described embodiment.

[Brief description of the drawings]

FIG. 1 is a block diagram showing the overall configuration of an embodiment of the present invention.

FIG. 2 is a diagram showing a communication procedure when transmitting an image file from a client 1 to a server 3.

FIG. 3 is a view showing logic for determining a storage format when an image file received by a server 3 is stored.

FIG. 4 is a diagram showing a communication procedure when an image file is transmitted from the server 3 to the client 1.

FIG. 5 is a diagram showing logic for determining a transmission format when the server 3 transmits an image file to the client 1.

FIG. 6 is a diagram showing a method for compressing and decompressing an image file.

[Explanation of symbols]

 Reference Signs List 1 client system (client) 3 server system (server) 13 receiving unit 15 JPEG unit 17 environment file 19 transmitting unit 101, 121 image file 103 header 105, 111 data

Claims (10)

[Claims] 1. A system for receiving and storing a file from a transmitting system that wants to transmit a file, and transmitting the stored file to a receiving system that wants to receive the file. A receiving unit for negotiating a receiving format when receiving the file with the transmitting system, and receiving the file in the receiving format from the transmitting system; and transmitting the file to the receiving system. After negotiating the transmission format with the receiving system,
A transmitting unit that transmits the file to the receiving side system; and, when receiving the file, determining a storage format for storing the file, storing the file in the storage format, and transmitting the file. Sometimes, a file format conversion unit that determines an actual transmission format for transmitting the file, passes the file to the actual transmission format, and passes the file to the transmission unit, wherein the storage format is the reception format and A file format that can be converted from the same or the receiving format, the actual transmission format is the same as the storage format or a file that can be converted from the storage format, and the receiving system can handle A file communication server in the form. 2. The file communication server according to claim 1, wherein when the receiving unit negotiates the receiving format with the transmitting system, a file format that can be handled by the transmitting system is set to the receiving format. 3. The file communication server according to claim 1, wherein when the transmission unit negotiates the transmission format with the receiving system, the transmission format is a file format that can be handled by the receiving system. 4. A setting storage format which is set in advance is stored, and when the file conversion unit determines the storage format,
If the setting storage format is the same as the reception format or can be converted from the reception format, the setting storage format is the storage format, and if the setting storage format cannot be converted from the reception format, 2. The file communication server according to claim 1, wherein another file format convertible from the reception format is set as the storage format. 5. When the file conversion unit determines the storage format, even if the setting storage format is convertible from the reception format, the file conversion unit may convert the reception format to the setting storage format. The file communication server according to claim 4, wherein, if disadvantageous from a viewpoint, another file format that is convertible from the reception format and more advantageous than the setting storage format is the storage format. 6. The file format converter, when determining the actual transmission format, when the transmission format negotiated with the receiving side system is the same as the storage format or when conversion from the storage format is possible, If the negotiated transmission format is the actual transmission format, and if the negotiated transmission format cannot be converted from the storage format, another file format that can be converted from the storage format and handled by the receiving system is used as the actual transmission format. 6. The file communication server according to claim 5, wherein the file communication server uses a transmission format. 7. The file communication server according to claim 1, wherein the file is an image file, and the file format is a compression format of the image file. 8. When converting the compression format of the image file, the file format conversion unit separates the image file into a header and data, performs the conversion only on the data, 8. The file communication server according to claim 7, wherein the file communication server creates the converted image file by combining the data. 9. A method for receiving and storing a file from a transmitting system that wants to transmit a file, and transmitting the stored file to a receiving system that wants to receive the file, the method comprising: Negotiating a reception format when the file is received with the transmission system; receiving the file in the reception format from the transmission system after negotiating with the transmission system; Determining a storage format for storing the file, and storing the file received in the storage format; and negotiating a transmission format when transmitting the file to the reception system with the reception system. And transmitting an actual transmission form for transmitting the saved file. Determining the stored file in the actual transmission format; and, after negotiating with the receiving system, transmitting the file in the actual transmission format to the receiving system. The storage format is the same as the reception format or a file format that can be converted from the reception format, and the actual transmission format is the same as the storage format or can be converted from the storage format, and A file communication method, which is a file format that can be handled by the receiving system. 10. A program for causing a computer to execute a method for receiving and storing a file from a transmitting system that wants to transmit a file and transmitting the stored file to a receiving system that wants to receive the file. In a computer-readable recording medium carried, the method comprises: negotiating a receiving format when receiving the file from the transmitting system with the transmitting system; and negotiating with the transmitting system, the receiving format. Receiving the received file from the transmission-side system, determining a storage format for storing the received file, and storing the file received in the storage format; Specify the transmission format when sending the file to the system. Negotiating with the receiving system; determining an actual transmission format for transmitting the stored file; converting the stored file into the actual transmission format; and after negotiating with the receiving system, Transmitting the file in the actual transmission format to the receiving side system, wherein the storage format is the same as the reception format or a file format convertible from the reception format; Is a file format that is the same as or can be converted from the storage format and is a file format that can be handled by the receiving system.