JP2006185134A - Network system and image delivery method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To enable a user to acquire specified image data by adding the specification of conversion parameters, when using a client device to make an image data acquisition request to a server for delivering image data. <P>SOLUTION: A network system 100 comprises the WWW server 102 for providing image data, and the client device 101 comprising an image data acquisition means for receiving requested image data from the WWW server and a conversion-specified image data acquisition request sending means for generating and sending a conversion-specified image data acquisition request with conversion parameters added for the acquisition of image data from the WWW server. The WWW server receives the conversion-specified image data acquisition request from the client device, interprets the received conversion-specified image data acquisition request to execute processing depending on the conversion specification, and sends converted image data thus generated to the client device. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a network system and an image distribution method, and more particularly to a server and a client device that perform transmission / reception of image data in a client-server network and a technique of image data conversion processing in the server.

  With the development of network technology, opportunities to receive images distributed by small devices such as mobile phones and personal digital assistants (PDAs) are increasing. The image data distribution service obtains image data by placing image data on a normal WWW server and designating the location of the image from a client terminal using a URI (Uniform Resource Identifier).

  FIG. 12 is a diagram showing the most general form of exchange for acquiring image data on a WWW server from a client device in a network system. In FIG. 12, an HTTP GET request is transmitted from the client device to the WWW server, and image data is transmitted to the client device as an HTTP response to the request. For example, http: // example. org / path / to / image. When acquiring image data specified by a URI of jpg, first, example. An HTTP GET request having the format shown in FIG. 13 is transmitted to the WWW server named org. The WWW server transmits the corresponding image data following the HTTP response header in the format shown in FIG. 14 to the client device. The client device processes the image data with reference to the header information of the HTTP response. Thereby, the image data of the WWW server can be acquired from the client device.

  However, particularly in the case of small devices, the processing capability is not so high, and there are many restrictions on the types of image formats that can be processed such as display, image resolution, image size, etc. Depending on the network environment of the device, it is necessary to reduce the amount of image data.

  As a method used to solve this problem, one original image data converted according to the type of terminal is prepared in advance and placed on a WWW server, and each image data is transferred from the client device. There is a way to keep it available. However, in this method, the image data distributor must convert the image data for each type of terminal, and it is difficult to deal with diversification of devices.

  The present invention has been made in view of such points, and in a client-server network system, when a user makes an image data acquisition request to a server that distributes image data using a client device, a conversion parameter is provided. It is an object of the present invention to provide a method capable of acquiring designated image data by adding the designation.

  Another object of the present invention is to provide a simple method capable of acquiring target image data without providing complicated means in a client device having a low processing capability such as a small device.

  The network system according to the present invention includes a WWW server that provides image data, an image data acquisition unit that receives image data requested from the WWW server, and the WWW in a network system that transmits and receives image data in a client-server network. A client device comprising a conversion designation-added image data acquisition request transmitting means for generating and sending an image data acquisition request with a conversion specification to which a conversion parameter is added when acquiring image data from the server, wherein the WWW server , A data acquisition request receiving unit with conversion specification for receiving the image data acquisition request with conversion specification from the client device, and an image data acquisition request with conversion specification received by the image data acquisition unit with conversion specification Image to be processed according to the specification And having a chromatography data conversion means and converting the processed image data transmitting means for transmitting the converted processed image data generated by the image data conversion processing unit to the client device.

  An image distribution method according to the present invention is an image distribution method in a network system that transmits and receives image data in a client-server network, and an image with a conversion specification to which a conversion parameter is added when acquiring image data from the WWW server. Generating and transmitting a data acquisition request, wherein the WWW server receives the image data acquisition request with conversion specification from the client device, interprets the received image data acquisition request with conversion specification, The method includes a step of performing processing in accordance with the conversion designation and a step of transmitting the converted image data to the client device.

  A program according to the present invention causes a computer to execute the image distribution method.

  The computer-readable recording medium of the present invention is characterized in that the program is recorded.

  According to the present invention, when a user makes an image data acquisition request using a client device to a server that distributes image data, image data obtained by converting original image data by adding a conversion parameter is added. Will be able to get.

  Further, according to the present invention, it is possible to provide a simple method capable of acquiring target image data without providing complicated means in a client apparatus having a low processing capability such as a small device.

  DESCRIPTION OF EXEMPLARY EMBODIMENTS Hereinafter, preferred embodiments to which the invention is applied will be described in detail with reference to the accompanying drawings.

  FIG. 1 is a diagram for explaining the principle of the network system of the present invention. In FIG. 1, a network system 100 has a client server type network configuration including a client apparatus 101 and a WWW server 102, and the client apparatus 101 and the WWW server 102 transmit and receive image data through a communication network 108.

  Further, the client apparatus 101 receives image data transmitted from the WWW server 102 and an image data acquisition request transmission unit 103 with a conversion designation that transmits a URI and conversion parameters of image data to the WWW server 102. The unit 104 is configured.

Further, the WWW server 102 receives a conversion designation-added data acquisition request receiving unit 105 that receives a conversion-designated image data acquisition request from the client apparatus 101, and an image data conversion processing unit 106 that interprets the conversion request and performs image data conversion processing. And a converted image data transmission unit 107 that transmits the converted image data to the client apparatus 101.
Here, the image data acquisition request with conversion designation will be described in detail with reference to FIG.

  As an example, the original image data is transferred to http: // example. org / path / to / image. Let us consider a case in which it is specified by a URI of svg, the resolution is 72 DPI, the aspect ratio is preserved, and the size is requested to be converted to JPEG image data of 480 pixels wide × 360 pixels high.

  First, the URI of the original image data of the image to be acquired is designated (step 201). Next, each conversion parameter is designated (step 202). The determination of each conversion parameter may be based on an operation of a user using the client apparatus 101 or may be automatically generated according to the processing capability of the device. Each conversion parameter in step 202 will be described later.

  Next, the conversion parameters generated in step 202 are connected with a “+” symbol to form one character string as shown in FIG. 3 (step 203).

  Next, the portion indicating the name of the URI WWW server of the image data designated in step 201 is separated from the path of the image data (step 204). The URI character string can be decomposed into a protocol identifier, a server name, and an image data path, as shown in FIG. org, / path / to / image. svg is cut out.

  Next, it is confirmed whether or not it exists correctly with the name of the WWW server cut out in step 204 (step 205, step 206), and if it does not exist, an error is output and the process ends (step 210). If there is a WWW server, an image data acquisition request character string with conversion designation is generated from the image data path cut out at step 204 and the conversion parameter character string generated at step 203 (step 207). The image data acquisition request character string with conversion designation generated in step 207 is expressed by a character string as shown in FIG. 5 according to the format of the HTTP GET request. Next, the image data acquisition request character string with conversion designation generated in step 207 is transmitted to the WWW server (step 208). When the processing at the WWW server is finished, the image data is received, and all processing is terminated (step 209).

  Next, the processing of the WWW server that receives the conversion-designated image data acquisition request character string transmitted from the client device in step 208 will be described using the flowchart shown in FIG.

  The WWW server waits until it receives a request from the client device. When the image data acquisition request character string with conversion specification transmitted from the client device is received (step 1001), the image data acquisition request character string with conversion specification is analyzed (step 1002). The received image data acquisition request character string with conversion designation has a format similar to the HTTP GET request 1101 shown in FIG. 11 as described above, and can be decomposed into a path 1102 and a conversion parameter 1103. It is checked whether or not the original image data file exists from the character string of the path 1102 (step 1003). If it does not exist, the status “404” (file does not exist) is transmitted to the client device as an HTTP response (step 1004). ).

  Here, the HTTP response transmitted in step 1004 will be described. FIG. 7 shows an HTTP response transmitted from the WWW server to the client device when there is no image data designated by the URI on the WWW server. Upon receiving this HTTP response, the client device recognizes that the specified file does not exist on the WWW server, and performs error processing.

  Returning to FIG. 10, if an image data file exists in step 1003, it is next checked whether or not all the conversion processes specified by the character string of the conversion parameter 1103 are possible (step 1005), and impossible processes are included. If so, status “501” (function not implemented) is transmitted to the client apparatus as an HTTP response (step 1006).

  Here, the HTTP response transmitted in step 1006 will be described. FIG. 8 shows an HTTP response transmitted from the WWW server to the client apparatus when part or all of the processing specified by the conversion parameter cannot be processed on the WWW server. By receiving this HTTP response, the client device recognizes that the conversion process designated on the WWW server has failed, and performs error processing.

  Returning to FIG. 10, when it is determined in step 1005 that the conversion process is possible, the conversion process is executed (step 1007), and the image data of the conversion process result is transmitted to the client device as an HTTP response (step 1008).

  Here, the HTTP response transmitted in step 1008 will be described. FIG. 6 shows image data received by the client device when the conversion process is successful in the WWW server. The first line describes the HTTP version and response status code, the second line describes the format of the received image data in the media type specified in RFC3023, and the third line shows the size of the image data in bytes. ing. The header information of the HTTP response is composed of the first to third lines. There is an empty row in the fourth row, and the fifth and subsequent rows are byte sequences of actual image data. As a result, the SVG file (media type: image / jpeg) is specified as the original image data on the client device side, but the image data is received as if the JPEG file was specified by the URI, and the display etc. Processing can be performed.

  Next, the conversion parameter specified in step 202 will be described. FIG. 9 explains the conversion parameter and its specifying method using BNF. Each conversion parameter in FIG. 9 will be described in detail.

  First, the description method of format designation will be described. Here, there are three types of formats that can be specified: SVG, JPEG, and PNG. A character string “svg” is described after “format =” when acquired in the SVG format, “jpg” when acquired in the JPEG format, and “png” when acquired in the PNG format. In addition, the format can be described with a “-” symbol in between. If multiple format formats are described using the "-" symbol, the first format format described on the leftmost side takes precedence. If the format cannot be converted on the server side, it indicates a request to convert to the second format format. ing. In other words, when “format = png−jpg” is described, the first format is the PNG format, and when the conversion to the PNG is impossible on the server side, the second format is used. This indicates that conversion in JPEG format is requested.

  Next, a method for specifying the resolution will be described. The resolution is specified by an integer having a unit of DPI, and is described after “resolution =”. The resolution can also be specified as a range, and an integer character string is connected by a “˜” (tilde) symbol. At that time, priority is given to the resolution that can be processed by the server close to the numerical value described on the left side. For example, when specifying the resolution between 300 DPI and 600 DPI and requesting processing at as high a resolution as possible, “resolution = 600 to 300” is described.

  Next, a method for specifying the size will be described. The size can be specified with the integer number of horizontal and vertical pixels. The aspect ratio is fixed as “preserve” when fixed, and as “non” when adjusted to the specified size without fixing. Express. These character strings are described in the order of “size =” followed by the number of vertical pixels, “x” symbol, horizontal pixel number, “@” symbol, and aspect ratio. For example, when it is requested to convert data with a fixed aspect ratio as data of horizontal 400 pixels and vertical 300 pixels, “size = 400 × 300 @ preserve” is described.

  Next, the designation of the clipping range will be described. The cropping range is a rectangular range parallel to the XY axis for the original image data. Specify the XY coordinate values of the upper left and lower right points of the rectangle, and set the X and Y coordinate values of the two points respectively. Connect with "x" symbol and connect each with "~" (tilde) symbol. For example, if the clipping range is a rectangle indicated by the upper left (10.5, 30) and the lower right (210, 315.5), “crop = 10.5 × 30 to 210 × 315.5” is described.

  Another object of the present invention is to supply a storage medium storing software program codes for realizing the functions of the above-described embodiments to a system or apparatus, and the computer (or CPU or MPU) of the system or apparatus stores the storage medium. Needless to say, this can also be achieved by reading and executing the program code stored in.

  In this case, the program code itself read from the storage medium realizes the functions of the above-described embodiments, and the program code itself and the storage medium storing the program code constitute the present invention.

  As a storage medium for supplying the program code, for example, a flexible disk, a hard disk, an optical disk, a magneto-optical disk, a CD-ROM, a CD-R, a magnetic tape, a nonvolatile memory card, a ROM, or the like can be used.

  Further, by executing the program code read by the computer, not only the functions of the above-described embodiments are realized, but also an OS (basic system or operating system) running on the computer based on the instruction of the program code. Needless to say, a case where the functions of the above-described embodiment are realized by performing part or all of the actual processing and the processing is included.

  Further, after the program code read from the storage medium is written in a memory provided in a function expansion board inserted into the computer or a function expansion unit connected to the computer, the function is determined based on the instruction of the program code. It goes without saying that the CPU or the like provided in the expansion board or function expansion unit performs part or all of the actual processing and the functions of the above-described embodiments are realized by the processing.

1 is a network diagram illustrating the principle of a network system according to an embodiment of the present invention. It is the flowchart which showed the flow of the process of the client apparatus in the network system which concerns on embodiment of this invention. It is a figure which shows the example of a description of the conversion parameter character string in embodiment of this invention. It is a figure explaining URI. It is a figure which shows the example of the HTTP GET request transmitted to a WWW server from a client apparatus. It is a figure which shows the example of the HTTP response when the process in a WWW server transmitted to a client apparatus from a WWW server succeeds. It is a figure which shows the example of an HTTP response when the original image data file designated on the WWW server does not exist transmitted to the client device from the WWW server. It is a figure which shows the example of the HTTP response when the conversion process designated on the WWW server which was transmitted to a client apparatus from a WWW server cannot be performed. It is the figure explaining the description method of each conversion parameter about a conversion parameter character string. It is the flowchart which showed the flow of the process of a WWW server. It is the figure explaining the process which analyzes the HTTP GET request which a WWW server receives from a client apparatus. It is the figure explaining transmission / reception of the data of a WWW server and a client apparatus in a general network system. It is the figure which showed the example of the HTTP GET request transmitted to a WWW server from a client apparatus in a general network system. It is the figure which showed the example of the HTTP response transmitted to a client apparatus from a WWW server in a general network system.

Explanation of symbols

DESCRIPTION OF SYMBOLS 100 Network system 101 Client apparatus 102 WWW server 103 Image data acquisition request transmission part with conversion specification 104 Image data reception part 105 Data acquisition request reception part with conversion specification 106 Image data conversion processing part 107 Conversion processed image data transmission part 108 Communication network

Claims (10)

In a network system that transmits and receives image data on a client-server network,
A WWW server that provides image data;
Image data acquisition means for receiving image data requested from the WWW server, and image data with conversion specification for generating and transmitting an image data acquisition request with conversion specification to which a conversion parameter is added when acquiring image data from the WWW server A client device having an acquisition request transmission means,
The WWW server
A data acquisition request receiving unit with conversion specification for receiving the image data acquisition request with conversion specification from the client device;
Image data conversion processing means for interpreting the image data acquisition request with conversion specification received in the image data acquisition means with conversion specification and performing processing according to the conversion specification;
A network system comprising: converted image data transmission means for transmitting the converted image data generated by the image data conversion processing means to a client device.   The network system according to claim 1, wherein the network system transmits and receives image data using an HTTP protocol.   The network system according to claim 1, wherein the data acquisition request with conversion designation is represented by a character string that combines a URI (Uniform Resource Identifier) for the WWW server and a conversion parameter.   The network system according to claim 1, wherein the client device transmits data in an HTTP GET request format to the WWW server in the network system.   The network system according to claim 1, wherein the WWW server transmits data in an HTTP response format to the client device in the network system.   When the WWW server interprets the data acquisition request with conversion designation received by the image conversion processing unit and finds that it cannot perform a part or all of the requested processing, the WWW server 6. The network system according to claim 5, wherein the fact is notified to that.   The network system according to claim 5, wherein the WWW server explicitly notifies the client device of the converted image data format. An image distribution method in a network system for transmitting and receiving image data in a client server type network,
Generating and transmitting an image data acquisition request with a conversion specification to which a conversion parameter is added when acquiring image data from the WWW server,
The WWW server
Receiving the image data acquisition request with the conversion designation from the client device;
Interpreting the received image data acquisition request with a conversion specification and performing a process according to the conversion specification;
And a step of transmitting the converted image data to the client device.   The program for making a computer perform the image delivery method of Claim 8.   A computer-readable recording medium on which the program according to claim 9 is recorded.

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