KR20160120017A - System for cloud streaming service, method of image cloud streaming service using process shortering and apparatus for the same - Google Patents

Abstract

Disclosed are a cloud streaming service system, an image cloud streaming service method using process shortening, and an apparatus therefor. The cloud streaming server of the present invention may receive an application executed screen, capture images corresponding to a changed portion of the application executed screen, determine whether the process shortening is applied to at least some of the captured images, acquire a compressed image corresponding to the at least a portion of a compressed image cache without encoding a still image when the process shortening is applied, and transmit the compressed image to a terminal of a user. At an image cloud streaming service, a still image encoding process for an image is shortened, so that it is possible to save resources of a cloud streaming server and increase a concurrent connection rate.

Description

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an image cloud streaming service method and an image cloud streaming service method using the stream cloud service system,

The present invention relates to a cloud streaming service system capable of saving resources of a server by shortening a process corresponding to still image encoding by utilizing a cache for storing still image encoded images in an image-based cloud streaming service, To an image cloud streaming service method and apparatus therefor.

The rapid development of the Internet has resulted in a rapid increase in the communication speed of an individual. The improvement in the communication speed can be achieved by downloading or uploading a large amount of data by accessing a computer located at a remote place, or by using a remote computer control program, As well as providing an environment in which a remote computer can be used.

In addition, as a variety of applications have been developed for mobile communication terminals such as smart phones, many virtualization technologies have been proposed for driving applications requiring high performance in relatively low performance user terminals.

Among them, the application is driven on the server, the driving screen is compressed through video encoding and transmitted to the client, and the client reproduces the transmitted video to generate a screen virtualization Cloud streaming service is becoming popular.

The cloud streaming service basically adopts the cloud streaming method based on the video codec. However, even when a static screen such as a menu display is serviced, the entire screen is unnecessarily captured and operated using a video codec, which makes the overall system ineffective.

Therefore, an image that can shorten the process of performing still image encoding in the entire process for providing a service using a cache for capturing and storing a captured still image, Based cloud streaming service technology.

Korean Patent Publication No. 2014-0047916, published on Apr. 23, 2014 (name: data compression apparatus and method, memory system including data compression apparatus)

An object of the present invention is to save resources of a cloud streaming server by shortening the process of performing still image encoding on an image in an image-based cloud streaming service.

It is another object of the present invention to provide a service with improved image quality by storing a screen having a high connection rate in a compressed image cache in advance among execution screens of an application before a user accesses a cloud streaming server.

It is another object of the present invention to provide a high-performance application execution screen even in a low-end terminal by processing only the changed image on the application execution screen and providing it to the user terminal.

According to an aspect of the present invention, there is provided a server including: a receiving unit for receiving an application execution screen; An abbreviation application determining unit for capturing images corresponding to the changed portions in the application execution screen and determining whether or not process shortening is applied to at least a part of the captured images; A process abbreviation for obtaining a compressed image corresponding to the at least a portion in a compressed image cache without performing still image encoding when the process abbreviation is applied; And a transmission unit for transmitting the compressed image to a user terminal.

In this case, the shortening application determining unit may calculate the at least some hash value, and may determine that the process shortening is applied when the compressed image corresponding to the hash value exists in the compressed image cache.

In this case, the cloud streaming server may further include a pre-compressed image caching unit for storing a still image encoding the at least one basic application execution screen among a plurality of application execution screens corresponding to the application, and storing the still image in the compressed image cache.

At this time, the pre-compressed image caching unit may store at least one of the original image of the at least one basic application execution screen and the compressed image generated by still image encoding the at least one basic application execution screen in the cache table of the compressed image cache .

At this time, the short-term application determining unit searches for a reference table item having a table address corresponding to the hash value among at least one table item constituting the cache table, and determines whether the original image included in the reference table item It can be determined that the compressed image exists when they are compared with each other.

At this time, the process shortening unit may obtain the compressed image included in the reference table item.

In this case, if the process shortening is not applied, the transmitting unit may perform still image encoding on the images and transmit the still image to the terminal.

At this time, the cloud streaming server may further include an additional caching unit for storing the still image encoded images in the compressed image cache before transmitting them to the terminal.

At this time, at least one basic application execution screen may include an application execution screen corresponding to a connection count of the plurality of application execution screens equal to or greater than a preset reference number, and an access step of the plurality of application execution screens, And may correspond to at least one of the application execution screens corresponding to the upper level.

According to another aspect of the present invention, there is provided an image cloud streaming service method using a process shortening method, comprising: receiving an application execution screen; Capturing images corresponding to changed portions of the application execution screen and determining whether process shortening is applied to at least some of the captured images; Obtaining a compressed image corresponding to the at least a portion in a compressed image cache without performing still image encoding when the process shortening is applied; And transmitting the compressed image to a user's terminal.

At this time, the determining step may calculate the at least some hash value, and determine that the process shortening is applied when the compressed image corresponding to the hash value exists in the compressed image cache.

In this case, the image cloud streaming service method may further include a step of encoding a still image of at least one basic application execution screen among a plurality of application execution screens corresponding to the application and storing the still image in the compressed image cache.

At this time, the storing step may store at least one of the original image of the at least one basic application execution screen and the compressed image generated by still image encoding the at least one basic application execution screen in the cache table of the compressed image cache have.

In this case, the determining step may include: searching a reference table item having a table address corresponding to the hash value among at least one table item constituting the cache table, and comparing the original image included in the reference table item with the at least a part It can be determined that the compressed image exists when they are compared with each other.

At this time, the step of acquiring the compressed image may acquire the compressed image included in the reference table item.

In this case, if the process shortening is not applied, the transmitting step may perform still image encoding on the images and transmit the still image to the terminal.

At this time, the image cloud streaming service method may further include storing the still image encoded images in the compressed image cache before transmitting them to the terminal.

At this time, at least one basic application execution screen may include an application execution screen corresponding to a connection count of the plurality of application execution screens equal to or greater than a preset reference number, and an access step of the plurality of application execution screens, And may correspond to at least one of the application execution screens corresponding to the upper level.

According to the present invention, resources of a cloud streaming server can be saved by shortening the process of performing still image encoding on an image in an image-based cloud streaming service.

In addition, the present invention can provide a service with improved image quality by storing a screen having a high connection rate among execution screens of an application beforehand in a compressed image cache before a user connects to a cloud streaming server.

In addition, according to the present invention, only the changed image is processed on the application execution screen and provided to the user terminal, thereby providing a high-performance application execution screen even in low-end terminals.

1 is a block diagram illustrating a cloud streaming service system according to an embodiment of the present invention.
2 is a block diagram illustrating an example of the cloud streaming server shown in FIG.
3 is a diagram illustrating a cache table of a compressed image cache according to an embodiment of the present invention.
FIG. 4 is a diagram illustrating a process for determining whether or not a process shortening is applied according to an embodiment of the present invention.
5 is a diagram illustrating a process of capturing images on an application execution screen according to an embodiment of the present invention.
6 is a flowchart illustrating an image cloud streaming service method using a process shortening process according to an exemplary embodiment of the present invention.
7 is a detailed flowchart illustrating an image cloud streaming service method using a process shortening process according to an embodiment of the present invention.
8 is a flowchart illustrating an image cloud streaming service process using a process shortening process according to an embodiment of the present invention.

Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings. In the following description and the accompanying drawings, detailed description of well-known functions or constructions that may obscure the subject matter of the present invention will be omitted. It should be noted that the same constituent elements are denoted by the same reference numerals as possible throughout the drawings. Embodiments of the present invention are provided to more fully describe the present invention to those skilled in the art. Accordingly, the shapes and sizes of the elements in the drawings and the like can be exaggerated for clarity.

The terms and words used in the present specification and claims should not be construed to be limited to ordinary or dictionary meanings and the inventor is not limited to the concept of terminology for describing his or her invention in the best way. It should be interpreted as meaning and concept consistent with the technical idea of the present invention. Therefore, the embodiments described in the present specification and the configurations shown in the drawings are merely the most preferred embodiments of the present invention, and not all of the technical ideas of the present invention are described. Therefore, It is to be understood that equivalents and modifications are possible. Also, the terms first, second, etc. are used for describing various components and are used only for the purpose of distinguishing one component from another component, and are not used to define the components.

1 is a block diagram illustrating a cloud streaming service system according to an embodiment of the present invention.

Referring to FIG. 1, a cloud streaming service system according to an embodiment of the present invention includes a cloud streaming server 110, terminals 120-1 to 120-N, and a network 130. FIG.

The cloud streaming server 110 receives an application execution screen.

In addition, the cloud streaming server 110 captures images corresponding to the changed portions of the application execution screen, and determines whether or not process shortening is applied to at least some of the captured images.

At this time, it is possible to calculate at least some hash values, and judge that the process shortening is applied when there is a compressed image corresponding to the hash value in the compressed image cache.

A reference table entry having a table address corresponding to a hash value of at least one table entry constituting the cache table is searched and at least a part of the original image included in the reference table entry is compared to find that a compressed image exists .

In addition, the cloud streaming server 110 obtains a compressed image corresponding to at least a portion of the compressed image cache, without performing still image encoding when process shortening is applied.

At this time, the compressed image contained in the reference table item can be obtained.

In addition, the cloud streaming server 110 transmits the compressed image to the user terminals 120-1 to 120-N.

At this time, if the process shortening is not applied, still image encoding on the images may be performed and transmitted to the terminals 120-1 to 120-N.

In addition, the cloud streaming server 110 may still image-encode at least one of the plurality of application execution screens corresponding to the application and store the same in the compressed image cache.

At this time, at least one of the original image of the at least one basic application execution screen and the compressed image generated by still image encoding of the at least one basic application execution screen may be stored in the cache table of the compressed image cache.

At this time, at least one basic application execution screen includes an application execution screen corresponding to a connection count of a plurality of application execution screens equal to or greater than a predetermined reference number, and an application execution screen corresponding to an access step among a plurality of application execution screens, Lt; RTI ID = 0.0 > application < / RTI >

In addition, the cloud streaming server 110 may further store the still image encoded images in a compressed image cache prior to transmission to the terminal.

The terminals 120-1 to 120-N receive an application execution screen corresponding to the cloud streaming service from the cloud streaming server 110 and provide them to the user.

The terminals 120-1 to 120-N are connected to a communication network and are capable of executing applications on the basis of a cloud computing system. The terminals 120-1 to 120-N are not limited to the mobile communication terminal but may be any information communication device, multimedia terminal, A fixed terminal and an IP (Internet Protocol) terminal. Each of the terminals 120-1 to 120-N may be a mobile phone, a portable multimedia player (PMP), a mobile Internet device (MID), a smart phone, a desktop, a tablet PC, A mobile terminal having various mobile communication specifications such as a notebook computer, a notebook computer, a netbook, a personal digital assistant (PDA), a smart TV, and an information communication device.

The terminals 120-1 to 120-N receive various kinds of information such as numeric and character information, set various functions, and input signals related to the function control of the terminals 120-1 to 120-N And can be transmitted to the control unit through the input unit. The input unit of the terminals 120-1 to 120-N may include at least one of a keypad and a touchpad for generating an input signal according to a user's touch or operation. At this time, the input units of the terminals 120-1 to 120-N are configured in the form of one touch panel (or touch screen) together with the display units of the terminals 120-1 to 120-N, Display function can be performed at the same time. The input unit of the terminals 120-1 to 120-N may be any type of input unit that can be developed in addition to an input unit such as a keyboard, a keypad, a mouse, a joystick, and the like. In particular, the input units of the terminals 120-1 to 120-N according to the present invention can transmit input signals for uploading or downloading contents based on cloud computing to the control units of the terminals 120-1 to 120-N.

In addition, the display unit of the terminals 120-1 to 120-N can display information on a series of operation states, operation results, and the like that occur during the performance of the functions of the terminals 120-1 to 120-N. In addition, the display units of the terminals 120-1 to 120-N can display menus of the terminals 120-1 to 120-N and user data input by the user. The display units of the terminals 120-1 to 120-N may be a liquid crystal display (LCD), a thin film transistor LCD (TFT-LCD), a light emitting diode (LED) An organic light emitting diode (OLED), an organic light emitting diode (AMOLED), an active matrix OLED, a retina display, a flexible display, and a three-dimensional display have. At this time, when the display units of the terminals 120-1 to 120-N are configured as touch screens, the display units of the terminals 120-1 to 120-N function as the input units of the terminals 120-1 to 120- Some or all of them. In particular, the display unit of the terminals 120-1 to 120-N according to the present invention can display information related to execution of content provided on a cloud computing basis on a screen.

The storage units of the terminals 120-1 to 120-N are devices for storing data, and include a main storage device and an auxiliary storage device, and are used for applications required for functional operations of the terminals 120-1 to 120- You can save the program. The storage units of these terminals 120-1 to 120-N may largely include a program area and a data area. Here, when the terminals 120-1 to 120-N activate the respective functions in response to a request from the user, the terminals 120-1 to 120-N provide the respective functions by executing the corresponding application programs under the control of the controller. In particular, the storage units of the terminals 120-1 to 120-N according to the present invention may store an operating system for booting the terminals 120-1 to 120-N, a program for uploading or downloading contents on the basis of cloud computing have. In addition, the storage units of the terminals 120-1 to 120-N may store information of a content DB storing a plurality of contents and information of the terminals 120-1 to 120-N. At this time, the content DB includes execution data for executing the content and attribute information about the content, and content usage information according to the execution of the content can be stored. The information of the terminals 120-1 to 120-N may include terminal specification information.

In addition, the communication units of the terminals 120-1 to 120-N may perform a function of transmitting and receiving data through the cloud streaming server 110 and the network 130. [ Here, the communication unit of the terminals 120-1 to 120-N may include RF transmitting means for up-converting and amplifying the frequency of the transmitted signal, RF receiving means for low-noise amplifying the received signal and down-converting the frequency . The communication units of the terminals 120-1 to 120-N may include at least one of a wireless communication module and a wired communication module. In the case where the terminals 120-1 to 120-N use wireless communication, the wireless communication module is a module for transmitting and receiving data according to a wireless communication method. The wireless communication module, the wireless LAN communication module, The data can be transmitted / received to / from the cloud streaming server 110 by using any one of them. The wired communication module is for transmitting / receiving data by wire. The wired communication module may connect to the network 130 through a wired network and transmit / receive data to / from the cloud streaming server 110. That is, the terminals 120-1 to 120-N access the network 130 using a wireless communication module or a wired communication module and transmit and receive data to and from the cloud streaming server 110 through the network 130. [ In particular, the network 130 according to the present invention can communicate with the cloud streaming server 110 or other terminals 120-1 to 120-N to transmit / receive data necessary for uploading or downloading content based on cloud computing.

The control unit of the terminal devices 120-1 to 120-N may be an operating system (OS) and a process unit for driving each configuration. For example, the control unit may include a cloud streaming server 110, When accessing the cloud streaming server 110 through a separate service application, it is possible to control the entire process of executing the service application according to the request of the user, and at the same time, It is possible to control the streaming server 110 to transmit the service use request and control the information of the terminals 120-1 to 120-N necessary for user authentication to be transmitted together.

In addition, the control units of the terminals 120-1 to 120-N can execute the specific contents stored in the storage units of the terminals 120-1 to 120-N according to the request of the user. At this time, the control unit may store the content usage history according to the execution of the content as the content usage information.

In addition, the control unit of the terminals 120-1 to 120-N may execute execution data for executing the content, content information including attribute information about the content, and content usage information, which is information according to the content usage history, And uploaded to the server 110 for uploading. Then, the controller transmits the uploaded content to the cloud streaming server 110, deletes the uploaded content from the storage unit of the terminals 120-1 to 120-N according to the user's request, connects to the cloud streaming server 110 The content may be executed through the cloud streaming server 110 and used.

In addition, the control units of the terminals 120-1 to 120-N may access the cloud streaming server 110 to download the content from the other terminals 120-1 to 120-N and control the content to be stored in the storage unit , It is also possible to control the content to be executed after receiving only data necessary for execution at the time of executing the content through the cloud streaming server 110.

The network 130 provides a path for transferring data between the cloud streaming server 110 and the terminals 120-1 to 120-N, and is a concept covering both existing networks and future developable networks . For example, the network 130 may be a wired / wireless local area network that provides communication of various information devices within a limited area, a mobile communication network that provides communication between mobile objects and mobile objects outside the mobile object, Or a wired / wireless communication network, or a combination of two or more. Meanwhile, the transmission scheme standard of the network 130 is not limited to the existing transmission scheme standard, and may include all transmission scheme standards to be developed in the future. In addition, the network used between the cloud streaming server 110 and the terminals 120-1 to 120-N in FIG. 1 may be different from the network used between the terminals 120-1 to 120-N, It may be the same.

2 is a block diagram illustrating an example of the cloud streaming server shown in FIG.

2, the cloud streaming server 110 shown in FIG. 1 includes a receiving unit 210, a pre-compressed image caching unit 220, a short-axis application determining unit 230, a process shortening unit 240, 250, an additional caching unit 260, and a storage unit 270.

The receiving unit 210 receives an application execution screen.

For example, when the user inputs a key through the terminal 120-1 shown in FIG. 1, the application server can receive information corresponding to the key input. The application server receiving the key input can execute the application, and the cloud streaming server 110 can receive the generated application execution screen through the receiving unit 210.

At this time, a key input of the user terminal can be obtained through a communication network such as the network shown in FIG. 1, or an application execution screen can be received from the application server.

The pre-compressed image caching unit 220 performs still image encoding of at least one basic application execution screen among a plurality of application execution screens corresponding to the application, and stores the still image in the compressed image cache. For example, assuming that the user first connects to the cloud streaming server, since there is no compressed image stored as still image encoding in the compressed image cache, it may be necessary to perform still image encoding to provide the service. In such a case, the reaction speed of the system may be slow and it may be an environment where it is difficult to provide a high-quality image.

Thus, before the user first connects to the cloud streaming server, basic application execution screens can be cached in the compressed image cache by virtually creating a user terminal. By caching basic application execution screens in this way, even if the user first connects to the cloud streaming server, the service according to the process shortening can be provided through the compressed image cache.

In addition, when still image encoding of basic application execution screens is performed through a key script input to a virtually created terminal, since the user is not actually connected, the still image encoding speed may be slow even if the speed is low. Therefore, even if the still image encoding is performed slowly, the image can be compressed with high image quality, so that the still image encoded high quality image can be cached in the compressed image cache and provided to the user.

At this time, at least one basic application execution screen can be compressed by the still image encoding method and stored in the compressed image cache. Also, the still image encoding method can be determined in consideration of the load generated in the cloud streaming server, the service speed, the image quality of the image, or the performance of the terminal receiving and rendering the encoded image. For example, to improve the speed of the cloud streaming service, you can compress the image with a palette PNG encoding method that has a high compression ratio and low load. In addition, if it is desired to provide a good image quality without regard to the load, the image can be compressed using the PNG 32-bit encoding method or the JPEG encoding method.

At this time, at least one original image of the basic application execution screen and at least one compressed image generated by still image encoding of the basic application execution screen can be stored in the cache table of the compressed image cache.

At this time, the cache table can store the original image and the compressed image corresponding to the preset number of tables. Also, the preset number of tables can store more tables if the cache space is large, depending on the performance of the compressed image cache.

In addition, the original image and the compressed image are matched and stored, respectively, so that the compressed image can be obtained easily through the comparison result of the original image retrieved using the hash value.

At this time, at least one basic application execution screen includes an application execution screen corresponding to a connection count of a plurality of application execution screens equal to or greater than a predetermined reference number, and an application execution screen corresponding to an access step among a plurality of application execution screens, Lt; RTI ID = 0.0 > application < / RTI >

That is, the basic application execution screen may correspond to a screen which is accessed a lot when users execute the application. For example, the first index screen or first page screen that appears when an application is launched may correspond. Also, when the menu items are listed in the approach step, the screen that can be accessed at a relatively high level in the menu item may correspond to the basic application execution screen.

Accordingly, it is possible to count the number of connections for each application execution screen by the users of the image cloud streaming service, and to set the application execution screen accessed by the users more than a preset reference number as a default application execution screen. Also, the application execution screen corresponding to the upper level of the access step may be set as the basic application execution screen based on the menu item.

For example, suppose you can access menus 2, 3, and 4 through a menu item 1 with an access step of 1, and access menus 5 and 6 through a menu item 2 with an access step of 2 have. At this time, if the preset reference step is the second step, the application execution screen corresponding to the first step whose access step is higher than the second step can be set as the basic application execution screen. That is, in the example, only the application execution screen corresponding to the menu 1 item can be set as the basic application execution screen.

The shortening application determining unit 230 captures images corresponding to changed portions in the application execution screen and determines whether or not the process shortening is applied to at least a part of the captured images.

The cloud streaming technique based on the video codec can capture and encode all the frames corresponding to the screen on which the application operates. However, when the frame-to-frame change on the screen on which the application operates is not large, the still-image encoding is performed by capturing only the change area of the changed frame as compared with the previous frame like the image-based cloud streaming technique, It is possible to display the parts except for the change area in the same manner and display only the change area.

At this time, it is possible to render the received application execution screen and to compare the frames of the rendered application execution screen and to capture the regions corresponding to the changed portion into the images. For example, if the current frame is compared with the previous frame when the current frame is compared with the previous frame, the changed area of the current frame can be captured as an image. In addition, the captured image may vary in size or quality according to an input signal input from a user terminal.

In addition, it is possible to detect intervals in which the frames change little between frames, and to capture the images in the intervals where there is little change between frames. For example, it may be inefficient to provide an image-based cloud streaming service because there are a large number of images to be captured with a large number of frames between frames. Accordingly, in such a period, a service can be performed through a cloud streaming technique based on a video codec, and an image of a changed region can be captured in order to perform an image-based cloud streaming service only in a period in which there is little change between frames.

At this time, it is possible to calculate the hash value of at least some of the images, and judge that the process shortening is applied when there is a compressed image corresponding to the hash value in the compressed image cache.

In this case, the hash value can be calculated using a hashing function used to convert the key value to the address of the storage location. That is, the address of the table to store the compressed image in the compressed image cache can be calculated as a hash value. Thus, for a good hashing function, the computation is fast and easy, and the computed address redundancy can be small. Representative hashing functions may include digit analysis, mid-square, division, folding, and radix conversion.

Therefore, in the present invention, it is possible to calculate the hash value using the captured images, and if the compressed image corresponding to the hash value exists in the compressed image cache, it can be determined that the process shortening using the compressed image can be applied . For example, a hash value can be calculated through a hashing algorithm that extracts bits at specific intervals for each of the images and performs XOR, SHIFT bit operations. Accordingly, it is possible to judge whether or not the process shortening is applied by judging whether a compressed image exists according to the table address corresponding to the calculated hash value.

At this time, a reference table entry having a table address corresponding to a hash value among at least one table entry constituting the cache table is searched, at least a part of the reference image entry included in the reference table entry is compared with the original image, It can be judged that there is a < / RTI >

For example, a still image encoded compressed image may be stored together with the original image for each table item constituting the cache table. Therefore, the table address assigned to each table item can be retrieved by using the hash value corresponding to the key value for retrieving the table value. At this time, the table address value may be the same value as the hash value.

Also, even if a reference table entry corresponding to the hash value is searched, the original image stored in the reference table entry may not match the image that calculated the hash value. For example, depending on the type and method of the hash algorithm, multiple images may use a single hash value. Therefore, after the reference table entry corresponding to the hash value is retrieved, the original image stored in the corresponding reference table item is compared with the captured image which computes the hash value, It can be determined that the image exists.

The process shortening unit 240 obtains a compressed image corresponding to at least a part of the images in the compressed image cache without performing still image encoding when process shortening is applied. That is, a compressed image can be obtained through a compressed image cache without performing a process of still image encoding in the entire process of the image-based cloud streaming service. Thus, the process shortening can be applied to obtain a compressed image, thereby saving the resources of the cloud streaming server.

At this time, the compressed image contained in the reference table item can be obtained. Through the hash value calculated using the captured image, the reference table item having the table address corresponding to the hash value can be searched, and the compressed image stored in the reference table item can be obtained.

The transmission unit 250 transmits the compressed image to the user terminal.

At this time, if the process shortening is not applied, still image encoding may be performed on the images to be transmitted to the terminal. That is, if there is no compressed image corresponding to the image captured in the compressed image cache, the process of still image encoding of the captured image can be performed since the processor can not be shortened. Thereafter, the still image encoding is performed and the generated compressed image is transmitted to the terminal to perform an image-based cloud streaming service.

The additional caching unit 260 further stores the still image encoded images in the compressed image cache before transmitting them to the terminal. That is, by caching the application execution screen having experience of accessing according to the usage pattern of the user in the compressed image cache, when the same application execution screen is requested from the user next, the network consumption amount and the transmission time are shortened to provide the service .

The storage unit 270 stores various information generated in the cloud streaming service process according to the embodiment of the present invention as described above.

According to an embodiment, the storage unit 270 may be configured independently of the cloud streaming server 110 to support a function for the cloud streaming service. At this time, the storage unit 270 may operate as a separate mass storage and may include a control function for performing operations.

In addition, the cloud streaming server 110 configured as described above may be implemented as one or more servers.

On the other hand, the cloud streaming server 110 can store information in the memory on which the memory is mounted. In one implementation, the memory is a computer-readable medium. In one implementation, the memory may be a volatile memory unit, and in other embodiments, the memory may be a non-volatile memory unit. In one implementation, the storage device is a computer-readable medium. In various different implementations, the storage device may comprise, for example, a hard disk device, an optical disk device, or any other mass storage device.

3 is a diagram illustrating a cache table of a compressed image cache according to an embodiment of the present invention.

Referring to FIG. 3, the cache table 310 of the compressed image cache according to an exemplary embodiment of the present invention may include a plurality of table entries.

At this time, each of the plurality of table items may be stored with the original image matching the compressed image, and a table address may be allocated to each of the plurality of table items.

According to FIG. 3, in order to retrieve a compressed image from the compressed image cache according to the present invention, it is first possible to capture images corresponding to the changed portion in the application execution screen.

Thereafter, the hash value may be computed using the image 320 corresponding to some of the captured images.

In this case, the hash value can be calculated using a hashing function, i.e., the hash algorithm 330, which is used to convert the key value to the address of the storage location. That is, the address of the table to store the compressed image in the compressed image cache can be calculated as a hash value.

For example, a hash value may be computed through a hash algorithm 330 that extracts bits at a specific interval for image 320 and performs XOR, SHIFT bit operations.

 Thereafter, a reference table item having an address corresponding to a hash value among at least one table item constituting the cache table of the compressed image cache can be searched.

In this case, the space for storing the original image 1 and the compressed image 1 in the cache table 310 may correspond to one table item, and the corresponding table item may be assigned a unique table address.

Accordingly, it is possible to determine whether a compressed image corresponding to the image 320 is stored in the compressed image cache by searching whether a table item allocated with the table address is present.

FIG. 4 is a diagram illustrating a process for determining whether or not a process shortening is applied according to an embodiment of the present invention.

Referring to FIG. 4, in the process of determining whether to apply the process shortening according to an embodiment of the present invention, the receiving unit 413 of the cloud streaming server 410 receives a basic application execution screen .

At this time, the cloud streaming server 410 can receive a basic application execution screen by generating a virtual terminal and performing a key script input.

Thereafter, in the pre-compressed image caching unit 411, the basic application execution screen is captured and still image encoded to generate a compressed image, and the generated compressed image can be stored in the compressed image cache.

Thus, even if the user first accesses the cloud streaming server 410 by caching the compressed image corresponding to the basic application execution screen in advance in the compressed image cache 412 before the user accesses the cloud streaming server 410, The service according to the shortening of the process can be provided through the process 412.

In addition, when still image encoding of basic application execution screens is performed through a key script input to a virtually created terminal, since the user is not actually connected, the still image encoding speed may be slow even if the speed is low. Therefore, even if the still image encoding is performed slowly, the image can be compressed with high image quality, so that the still image encoded high quality image can be cached in the compressed image cache and provided to the user.

Thereafter, the user accesses the cloud streaming server 410 through the terminal 420, and the cloud streaming server 410 can receive the application execution screen according to the user request from the application server 400. [

Thereafter, the shortening application determining unit 414 may capture the images corresponding to the changed portions in the application execution screen received, and determine whether or not the process shortening is applied to at least a part of the captured images.

That is, a compressed image can be obtained in the compressed image cache 412 to determine whether the compressed image can be provided to the terminal 420 without performing the still image encoding, that is, whether the process shortening is applied.

At this time, the short-axis application determining unit 414 calculates a hash value for at least some of the images, and calculates a hash value corresponding to the hash value among the at least one table item constituting the cache table of the compressed image cache 412 It is possible to judge whether or not the process shortening is applied by searching whether a reference table item having an address exists.

Thereafter, when the process shortening is applied, the process shortening unit 415 acquires a compressed image from the compressed image cache 412 and transmits the compressed image to the terminal 420 through the transmitting unit 416, The encoding process can provide a shortened image cloud streaming service.

In addition, if the process shortening is not applied, the transmitting unit 416 may still image-encode the images and transmit them to the terminal 420.

At this time, still image-encoded images may be additionally stored in the compressed image cache 412 through the additional caching unit 417. [

5 is a diagram illustrating a process of capturing images on an application execution screen according to an embodiment of the present invention.

Referring to FIG. 5, in the process of capturing images according to the present invention, first, frames of a small change in the screen can be obtained in an application execution screen according to a user request.

At this time, it may be more efficient to provide the application execution screen to the user through the cloud streaming service based on the video codec for the part where the screen changes much.

Thereafter, the current frame 520 and the previous frame 510 among the frames of the small change portion can be compared. For example, when comparing the current frame 520 and the previous frame 510 shown in FIG. 5, there is no change in the A region and the B region of the two frames. However, the C region and the D region of the previous frame 510, (520), it can be confirmed that C 'and D'.

Thus, the cloud streaming server can identify such changes and capture the changed C 'and D' regions into the changed regions 530. That is, an image corresponding to the changed area 530 at the capture end of the cloud streaming server can be captured.

When the current frame 520 and the previous frame 510 are compared with each other, if a plurality of regions are identified as the changed region 530, one region including all the changed regions is referred to as a changed region 530 ) Can be recognized and captured. In addition, it is also possible to recognize various changed areas as the changed areas 530 and to capture a plurality of changed areas 530 to perform an image-based cloud streaming service.

6 is a flowchart illustrating an image cloud streaming service method using a process shortening process according to an exemplary embodiment of the present invention.

Referring to FIG. 6, an image cloud streaming service method using a process shortening according to an embodiment of the present invention receives an application execution screen (S610).

For example, when the user inputs a key through the terminal 120-1 shown in FIG. 1, the application server can receive information corresponding to the key input. The application server receiving the key input can execute the application and the cloud streaming server can receive the generated application execution screen.

At this time, a key input of the user terminal can be obtained through a communication network such as the network shown in FIG. 1, or an application execution screen can be received from the application server.

6, an image cloud streaming service method using a process shortening method according to an exemplary embodiment of the present invention includes at least one application execution screen of a plurality of application execution screens corresponding to an application, And stores it in the compressed image cache. For example, assuming that the user first connects to the cloud streaming server, since there is no compressed image stored as still image encoding in the compressed image cache, it may be necessary to perform still image encoding to provide the service. In such a case, the reaction speed of the system may be slow and it may be an environment where it is difficult to provide a high-quality image.

Thus, before the user first connects to the cloud streaming server, basic application execution screens can be cached in the compressed image cache by virtually creating a user terminal. By caching basic application execution screens in this way, even if the user first connects to the cloud streaming server, the service according to the process shortening can be provided through the compressed image cache.

In addition, when still image encoding of basic application execution screens is performed through a key script input to a virtually created terminal, since the user is not actually connected, the still image encoding speed may be slow even if the speed is low. Therefore, even if the still image encoding is performed slowly, the image can be compressed with high image quality, so that the still image encoded high quality image can be cached in the compressed image cache and provided to the user.

At this time, at least one basic application execution screen can be compressed by the still image encoding method and stored in the compressed image cache. Also, the still image encoding method can be determined in consideration of the load generated in the cloud streaming server, the service speed, the image quality of the image, or the performance of the terminal receiving and rendering the encoded image. For example, to improve the speed of the cloud streaming service, you can compress the image with a palette PNG encoding method that has a high compression ratio and low load. In addition, if it is desired to provide a good image quality without regard to the load, the image can be compressed using the PNG 32-bit encoding method or the JPEG encoding method.

At this time, at least one original image of the basic application execution screen and at least one compressed image generated by still image encoding of the basic application execution screen can be stored in the cache table of the compressed image cache.

At this time, the cache table can store the original image and the compressed image corresponding to the preset number of tables. Also, the preset number of tables can store more tables if the cache space is large, depending on the performance of the compressed image cache.

In addition, the original image and the compressed image are matched and stored, respectively, so that the compressed image can be obtained easily through the comparison result of the original image retrieved using the hash value.

At this time, at least one basic application execution screen includes an application execution screen corresponding to a connection count of a plurality of application execution screens equal to or greater than a predetermined reference number, and an application execution screen corresponding to an access step among a plurality of application execution screens, Lt; RTI ID = 0.0 > application < / RTI >

That is, the basic application execution screen may correspond to a screen which is accessed a lot when users execute the application. For example, the first index screen or first page screen that appears when an application is launched may correspond. Also, when the menu items are listed in the approach step, the screen that can be accessed at a relatively high level in the menu item may correspond to the basic application execution screen.

Accordingly, it is possible to count the number of connections for each application execution screen by the users of the image cloud streaming service, and to set the application execution screen accessed by the users more than a preset reference number as a default application execution screen. Also, the application execution screen corresponding to the upper level of the access step may be set as the basic application execution screen based on the menu item.

For example, suppose you can access menus 2, 3, and 4 through a menu item 1 with an access step of 1, and access menus 5 and 6 through a menu item 2 with an access step of 2 have. At this time, if the preset reference step is the second step, the application execution screen corresponding to the first step whose access step is higher than the second step can be set as the basic application execution screen. That is, in the example, only the application execution screen corresponding to the menu 1 item can be set as the basic application execution screen.

In addition, the image cloud streaming service method using the process shortening according to an embodiment of the present invention captures images corresponding to the changed portions in the application execution screen (S620), and determines whether the process shortening is applied to at least a part of the captured images (S625).

The cloud streaming technique based on the video codec can capture and encode all the frames corresponding to the screen on which the application operates. However, when the frame-to-frame change on the screen on which the application operates is not large, the still-image encoding is performed by capturing only the change area of the changed frame as compared with the previous frame like the image-based cloud streaming technique, It is possible to display the parts except for the change area in the same manner and display only the change area.

At this time, it is possible to render the received application execution screen and to compare the frames of the rendered application execution screen and to capture the regions corresponding to the changed portion into the images. For example, if the current frame is compared with the previous frame when the current frame is compared with the previous frame, the changed area of the current frame can be captured as an image. In addition, the captured image may vary in size or quality according to an input signal input from a user terminal.

In addition, it is possible to detect intervals in which the frames change little between frames, and to capture the images in the intervals where there is little change between frames. For example, it may be inefficient to provide an image-based cloud streaming service because there are a large number of images to be captured with a large number of frames between frames. Accordingly, in such a period, a service can be performed through a cloud streaming technique based on a video codec, and an image of a changed region can be captured in order to perform an image-based cloud streaming service only in a period in which there is little change between frames.

At this time, it is possible to calculate the hash value of at least some of the images, and judge that the process shortening is applied when there is a compressed image corresponding to the hash value in the compressed image cache.

In this case, the hash value can be calculated using a hashing function used to convert the key value to the address of the storage location. That is, the address of the table to store the compressed image in the compressed image cache can be calculated as a hash value. Thus, for a good hashing function, the computation is fast and easy, and the computed address redundancy can be small. Representative hashing functions may include digit analysis, mid-square, division, folding, and radix conversion.

Therefore, in the present invention, it is possible to calculate the hash value using the captured images, and if the compressed image corresponding to the hash value exists in the compressed image cache, it can be determined that the process shortening using the compressed image can be applied . For example, a hash value can be calculated through a hashing algorithm that extracts bits at specific intervals for each of the images and performs XOR, SHIFT bit operations. Accordingly, it is possible to judge whether or not the process shortening is applied by judging whether a compressed image exists according to the table address corresponding to the calculated hash value.

At this time, a reference table entry having a table address corresponding to a hash value among at least one table entry constituting the cache table is searched, at least a part of the reference image entry included in the reference table entry is compared with the original image, It can be judged that there is a < / RTI >

For example, a still image encoded compressed image may be stored together with the original image for each table item constituting the cache table. Therefore, the table address assigned to each table item can be retrieved by using the hash value corresponding to the key value for retrieving the table value. At this time, the table address value may be the same value as the hash value.

Also, even if a reference table entry corresponding to the hash value is searched, the original image stored in the reference table entry may not match the image that calculated the hash value. For example, depending on the type and method of the hash algorithm, multiple images may use a single hash value. Therefore, after the reference table entry corresponding to the hash value is retrieved, the original image stored in the corresponding reference table item is compared with the captured image which computes the hash value, It can be determined that the image exists.

As a result of the judgment in the step S625, if the process shortening is applied, the image cloud streaming service method using the process shortening according to the embodiment of the present invention does not perform the still image encoding, (S630). That is, a compressed image can be obtained through a compressed image cache without performing a process of still image encoding in the entire process of the image-based cloud streaming service. Thus, the process shortening can be applied to obtain a compressed image, thereby saving the resources of the cloud streaming server.

At this time, the compressed image contained in the reference table item can be obtained. Through the hash value calculated using the captured image, the reference table item having the table address corresponding to the hash value can be searched, and the compressed image stored in the reference table item can be obtained.

As a result of the determination in step S625, if the process shortening is not applied, the image cloud streaming service method using the process shortening according to the embodiment of the present invention performs still image encoding on the images (S640). That is, if there is no compressed image corresponding to the image captured in the compressed image cache, the process of still image encoding of the captured image can be performed since the processor can not be shortened. Thereafter, the still image encoding is performed and the generated compressed image is transmitted to the terminal to perform an image-based cloud streaming service.

In addition, the image cloud streaming service method using the process shortening according to an embodiment of the present invention transmits the compressed image to the user terminal (S650).

Also, although not shown in FIG. 6, the image cloud streaming service method using the process shortening according to an embodiment of the present invention further stores the still image encoded images in the compressed image cache before transmitting them to the terminal. That is, by caching the application execution screen having experience of accessing according to the usage pattern of the user in the compressed image cache, when the same application execution screen is requested from the user next, the network consumption amount and the transmission time are shortened to provide the service .

Although not shown in FIG. 6, the image cloud streaming service method using the process shortening according to the embodiment of the present invention stores various information generated in the cloud streaming service process according to the embodiment of the present invention do.

According to the embodiment, the storage unit for storing various information generated in the cloud streaming service process may be configured independently of the cloud streaming server to support the function for the cloud streaming service. At this time, the storage unit may operate as a separate mass storage and may include a control function for performing operations.

In addition, the cloud streaming server configured as described above may be implemented as one or more servers.

On the other hand, the cloud streaming server can store information in the device by loading the memory. In one implementation, the memory is a computer-readable medium. In one implementation, the memory may be a volatile memory unit, and in other embodiments, the memory may be a non-volatile memory unit. In one implementation, the storage device is a computer-readable medium. In various different implementations, the storage device may comprise, for example, a hard disk device, an optical disk device, or any other mass storage device.

7 is a detailed flowchart illustrating an image cloud streaming service method using a process shortening process according to an exemplary embodiment of the present invention.

Referring to FIG. 7, an image cloud streaming service method using a process shortening according to an embodiment of the present invention receives a basic application execution screen from an application server through a virtual terminal (S702).

At this time, the basic script execution screen can be received by performing the key script input through the virtual terminal.

At this time, the basic application execution screen may correspond to a screen which is accessed a lot when users execute the application. For example, the first index screen or first page screen that appears when an application is launched may correspond.

Thereafter, the basic application execution screen is captured and still image encoded, and the generated compressed image is pre-cached in the compressed image cache (S704).

At this time, since the user is not actually connected, it may not be a problem even if the still image encoding speed is slow. Therefore, even if the still image encoding is performed slowly, the image can be compressed with high image quality, so that the still image encoded high quality image can be cached in the compressed image cache and provided to the user.

At this time, at least one basic application execution screen can be compressed by the still image encoding method and stored in the compressed image cache. Also, the still image encoding method can be determined in consideration of the load generated in the cloud streaming server, the service speed, the image quality of the image, or the performance of the terminal receiving and rendering the encoded image. For example, to improve the speed of the cloud streaming service, you can compress the image with a palette PNG encoding method that has a high compression ratio and low load. In addition, if it is desired to provide a good image quality without regard to the load, the image can be compressed using the PNG 32-bit encoding method or the JPEG encoding method.

Thereafter, an application execution screen corresponding to the user request is received (S706).

At this time, a key input of the user terminal can be obtained through a communication network such as the network shown in FIG. 1, or an application execution screen can be received from the application server.

Thereafter, the images corresponding to the changed portions on the application execution screen are captured (S708).

At this time, it is possible to render the received application execution screen and to compare the frames of the rendered application execution screen and to capture the regions corresponding to the changed portion into the images.

In addition, it is possible to detect intervals in which the frames change little between frames, and to capture the images in the intervals where there is little change between frames.

Thereafter, a hash value of at least a part of the captured images is calculated (S710).

In this case, the hash value can be calculated using a hashing function used to convert the key value to the address of the storage location. That is, the address of the table to store the compressed image in the compressed image cache can be calculated as a hash value. For example, a hash value can be calculated through a hashing algorithm that extracts bits at specific intervals for each of the images and performs XOR, SHIFT bit operations.

Thereafter, it is determined whether a reference table item having a table address corresponding to the hash value calculated in the cache table among at least one table item constituting the compressed image cache exists (S712). For example, a still image encoded compressed image may be stored together with the original image for each table item constituting the cache table. Therefore, the table address assigned to each table item can be retrieved by using the hash value corresponding to the key value for retrieving the table value. At this time, the table address value may be the same value as the hash value.

If it is determined in step S712 that there is a reference table item having a table address corresponding to the hash value, it is determined whether the original image stored in the reference table item matches the image in which the hash value is calculated (step S714).

At this time, even if a reference table item corresponding to the hash value is searched, the original image stored in the reference table item may not match the image that has calculated the hash value. For example, depending on the type and method of the hash algorithm, multiple images may use a single hash value. Therefore, after the reference table entry corresponding to the hash value is retrieved, the original image stored in the corresponding reference table item is compared with the captured image which computes the hash value, It can be determined that the image exists.

If it is determined in step S714 that the original image stored in the reference table item matches the image in which the hash value is calculated, the still image is not encoded and the compressed image stored in the reference table item is matched with the original image (S716) . That is, a compressed image can be obtained through a compressed image cache without performing a process of still image encoding in the entire process of the image-based cloud streaming service. Thus, the process shortening can be applied to obtain a compressed image, thereby saving the resources of the cloud streaming server.

If it is determined in step S712 that there is no reference table item having a table address corresponding to the hash value, still images are encoded in step S718 and cached in the compressed image cache in step S720. That is, if there is no compressed image corresponding to the image captured in the compressed image cache, the process of still image encoding of the captured image can be performed since the processor can not be shortened.

In addition, by caching the application execution screen having the experience of accessing according to the usage pattern of the user in the compressed image cache, when the same application execution screen is requested by the user, the network consumption amount and the transmission time are shortened to provide the service .

If it is determined in step S714 that the original image stored in the reference table item does not match the image in which the hash value is calculated, it is determined that the hash value has been calculated to be duplicated, the error of the hash value is corrected in step S722, S718).

Thereafter, the compressed image generated in the compressed image cache or still image encoded is transmitted to the user terminal (S724).

8 is a flowchart illustrating an image cloud streaming service process using a process shortening process according to an embodiment of the present invention.

Referring to FIG. 8, in step S802, the cloud streaming server 820 generates a virtual terminal to perform the pre-image caching in the image cloud streaming service process using the process shortening according to an embodiment of the present invention.

Thereafter, key input is performed to the application server 810 using the virtual terminal (S804).

Thereafter, the application server 810 executes the application corresponding to the key input (S806).

Thereafter, the application server 810 transmits the basic application execution screen generated by executing the application to the cloud streaming server 810 (S808).

Thereafter, the cloud streaming server 820 captures images corresponding to the received basic application execution screen (S810).

Thereafter, the captured images are compressed by a still image encoding method (S812), and a pre-cache is performed on the compressed image cache 630 (S814).

Thereafter, when a user key input is generated from the user terminal 840 (S816), the application server 810 executes an application corresponding to the user key input (S818).

Thereafter, the application server 810 transmits an application execution screen corresponding to the user key input to the cloud streaming server 820 (S820).

Thereafter, the image corresponding to the changed portion in the application execution screen is captured (S822), and a hash value of at least a part of the captured images is calculated (S824).

Thereafter, a reference table item having a table address corresponding to a hash value of at least one table item constituting the cache table of the compressed image cache 830 is searched (S826).

Thereafter, the source image is obtained from the reference table item (S828), and the hash value is compared with the calculated image (S830).

Thereafter, the images are matched (S832), the cloud streaming server 820 does not perform the still image encoding, and the compressed image cache 830 transfers the compressed image to the cloud streaming server 820 (S834).

Thereafter, the cloud streaming server 820 transmits the compressed image to the terminal 840 (S836).

Thereafter, the terminal 840 renders the received compressed image (S838) and displays it to the user (S840).

The image cloud streaming service method using the process shortening according to the present invention can be implemented in the form of a program command which can be executed through various computer means and recorded in a computer readable medium. The computer-readable medium may include program instructions, data files, data structures, and the like, alone or in combination. The program instructions recorded on the medium may be those specially designed and constructed for the present invention or may be available to those skilled in the art of computer software. Examples of computer-readable media include magnetic media such as hard disks, floppy disks and magnetic tape; optical media such as CD-ROMs and DVDs; magnetic media such as floppy disks; Includes all types of hardware devices that are specially configured to store and execute magneto-optical media and program instructions such as ROM, RAM, flash memory, and the like. Examples of program instructions may include machine language code such as those generated by a compiler, as well as high-level language code that may be executed by a computer using an interpreter or the like. Such a hardware device may be configured to operate as one or more software modules to perform the operations of the present invention, and vice versa.

As described above, the cloud streaming service system, the image cloud streaming service method using the process shortening method, and the apparatus therefor according to the present invention are not limited to the configuration and method of the embodiments described above, The examples may be constructed by selectively combining all or a part of each embodiment so that various modifications can be made.

According to the present invention, there is provided an image processing method including receiving an application execution screen, capturing images corresponding to changed portions in an application execution screen, determining whether or not process shortening is applied to at least a part of the captured images, It is possible to obtain a compressed image corresponding to at least a part of the compressed image cache without performing still image encoding and to transmit the compressed image to the user's terminal. Further, in the image-based cloud streaming service, it is possible to simultaneously provide services to more users at the same time by using resources of the cloud streaming server, and it is possible to provide a high-quality service through high-quality images stored in the cache .

110, 410, 820: Cloud streaming server
120-1 to 120-N, 420, and 840:
130: network 210, 413:
220, 411: Pre-compression image caching unit
230, 414: short axis application determining unit 240, 415:
250, 416: Transmitting unit 260, 417: Additional caching unit
270: storage unit 310: cache table
320: image 330: hash algorithm
400, 810: application server 412, 830: compressed image cache
510: previous frame 520: current frame
530: captured image

Claims (10)

A receiving unit for receiving an application execution screen;
An abbreviation application determining unit for capturing images corresponding to the changed portions in the application execution screen and determining whether or not process shortening is applied to at least a part of the captured images;
A process abbreviation for obtaining a compressed image corresponding to the at least a portion in a compressed image cache without performing still image encoding when the process abbreviation is applied; And
A transmission unit for transmitting the compressed image to a user terminal
Wherein the server comprises: The method according to claim 1,
The shortening application determining unit
Wherein the determining step determines that the process shortening is applied when the compressed image corresponding to the hash value exists in the compressed image cache. The method of claim 2,
The cloud streaming server
Further comprising: a pre-compressed image caching unit that performs still image encoding of at least one basic application execution screen among a plurality of application execution screens corresponding to the application and stores the still image in the compressed image cache. The method of claim 3,
The pre-compressed image caching unit
Wherein at least one of the at least one basic application execution screen and the at least one basic application execution screen is stored in the cache table of the compressed image cache. . The method of claim 4,
The shortening application determining unit
Searching for a reference table item having a table address corresponding to the hash value among at least one table item constituting the cache table, comparing the at least one part with the original image included in the reference table item, And determines that the compressed image exists. The method of claim 5,
The process shortening part
And obtains the compressed image included in the reference table item. The method of claim 2,
The transmitter
And if the process shortening is not applied, performs still image encoding on the images and transmits the still image to the terminal. The method of claim 7,
The cloud streaming server
Further comprising an additional caching unit for storing the still image encoded images in the compressed image cache before transmitting them to the terminal. The method of claim 3,
The at least one basic application execution screen
An application execution screen corresponding to a connection count of the plurality of application execution screens corresponding to a preset reference number or more and an application execution screen corresponding to a higher level than an access step of the plurality of application execution screens, Of the cloud streaming server. Receiving an application execution screen;
Capturing images corresponding to changed portions of the application execution screen and determining whether process shortening is applied to at least some of the captured images;
Obtaining a compressed image corresponding to the at least a portion in a compressed image cache without performing still image encoding when the process shortening is applied; And
Transmitting the compressed image to a user terminal
The method comprising the steps of: (a)

Images