KR20160015123A - System for cloud streaming service, method of cloud streaming service based on still image and apparatus for the same - Google Patents

Abstract

A cloud streaming service system, still image-based cloud streaming service method and apparatus therefor are disclosed. A still image compression method is selected in consideration of at least one of a size and an image property of the change area, and a change area encoded by the still image compression method is displayed to the user So that the still image based cloud streaming service can be performed. It is possible to improve the compression efficiency of still images and the speed of cloud streaming service by using still image compression method suitable for the situation when providing still image based cloud streaming service.

Description

TECHNICAL FIELD [0001] The present invention relates to a cloud streaming service system, a still image-based cloud streaming service method, and a device for the same. BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a cloud streaming service system,

The present invention relates to a cloud streaming service capable of improving compression efficiency and service speed by selecting and encoding a compression scheme according to a captured screen when providing a still image-based cloud streaming service for a portion of a cloud streaming service, System, a still image-based cloud streaming service method, and an apparatus therefor.

Due to the rapid development of the modern Internet, the communication speed of an individual has been dramatically improved. As a result of this communication speed, it is possible to access or download a large amount of data by connecting to a remote computer, As a result, an environment where remote computers can be used has been established.

In addition, 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 provide a screen virtualization Cloud streaming service is becoming popular.

This 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 served, the entire screen is unnecessarily captured and operated using a video codec, which is inefficient in operating the cloud streaming service system.

Korean Patent Laid-Open No. 10-2014-0076668, published on June 23, 2013 (name: game providing method, system, client terminal and service apparatus based on cloud streaming)

It is an object of the present invention to improve the compression efficiency and the speed of the cloud streaming service by using a still image compression technique that is suitable for a still image based cloud streaming service.

It is also an object of the present invention to provide streaming extrusion efficiency through a still image-based cloud streaming service, thereby providing a cloud streaming service for a faster and more users over the same band.

According to an aspect of the present invention, there is provided a cloud streaming server comprising: a capture unit for capturing a change area included in a changed frame compared with a previous frame; Selecting a still image compression scheme considering at least one of a size of the change area and an image property corresponding to the change area, and using the still image compression scheme, An encoding unit encoding a still image; And a sender for transmitting the still image-encoded change area to the user to perform a still image based cloud streaming service.

At this time, the encoding unit can compress the change area using a still image compression technique of any one of portable network graphics (PNG), portable network graphics (PNG), and joint experts group (JPEG).

In this case, if the size of the change area is less than a preset reference value, the encoding unit may encode the change area using the PNG still image compression scheme.

In this case, if the size of the change area is equal to or larger than the reference value, the encoding unit may select the still image compression scheme considering the image property.

In this case, the encoding unit may encode the change area using the JPEG still image compression scheme when the image quality is a natural image.

In this case, the encoding unit may encode the change area by applying the palette PNG still image compression scheme when the size of the change area is equal to or greater than a preset reference value and the image property is a synthetic image.

In this case, when the image property is an image in which the natural image and the synthetic image are mixed, the encoding unit may include a region corresponding to the natural image of the change region and a region corresponding to the composite image, The still image compression technique can be selected according to image characteristics corresponding to more areas.

In this case, the capturing unit may capture the changed area compared with the screen area corresponding to the previous frame among the screen areas corresponding to the changed frame.

At this time, the capture unit detects an interval in which a frame change is small in the entire frame to be transmitted to the terminal apparatus of the user, and captures the change area in a section in which the frame change is small.

At this time, the capturing unit detects an event type of the application generated from the terminal device of the user, and can detect an interval in which the frame change is small.

Also, a still image-based cloud streaming service method according to the present invention includes: capturing a change area included in a changed frame compared with a previous frame; Selecting a still image compression scheme considering at least one of a size of the change area and an image property corresponding to the change area, and using the still image compression scheme, Encoding a still image; And transmitting the still image-encoded change area to the user to perform a still image-based cloud streaming service.

At this time, the encoding step may compress the change area using a still image compression technique of any one of portable network graphics (PNG), portable network graphics (PNG), and joint experts group (JPEG).

In this case, when the size of the change area is less than a preset reference value, the encoding step may encode the change area using the PNG still image compression technique.

In this case, when the size of the change area is equal to or larger than the reference value, the still image compression method may be selected in consideration of the image property.

In this case, the encoding step may encode the change area using the JPEG still image compression scheme when the image quality is a natural image.

In this case, the encoding step can encode the change area by applying the palette PNG still image compression scheme when the size of the change area is equal to or larger than a preset reference value and the image property is a synthetic image .

In this case, the step of encoding may include the step of, when the image property is an image in which the natural image and the synthetic image are mixed, a region corresponding to the natural image, The still image compression technique can be selected according to image characteristics corresponding to more areas.

In this case, the capturing may capture the changed area compared with the screen area corresponding to the previous frame among the screen areas corresponding to the changed frame.

In this case, the step of capturing includes detecting an interval in which a frame change is small, of the entire frame to be transmitted to the terminal device of the user, and the change area can be captured in a section in which the frame change is small.

At this time, the detecting step detects an event type of the application generated from the terminal device of the user, and can detect an interval in which the frame change is small.

As another means for solving the problem of the present invention, there is provided a computer program stored in a medium for executing the above-described method.

In addition, the cloud streaming service system according to the present invention captures a change area included in a changed frame compared with a previous frame, and determines whether or not the still image a still image compression method is used to still image encode the change area corresponding to one frame using the still image compression technique and transmits the still image encoded change area to the user, A cloud streaming server for performing a cloud streaming service; And a terminal receiving an application execution result screen corresponding to the cloud streaming service from the cloud streaming server.

According to the present invention, it is possible to improve the compression efficiency of an image and the speed of a cloud streaming service by using a still image compression technique that is suitable for a still image based cloud streaming service.

Also, the present invention maximizes the streaming compression efficiency through the still image-based cloud streaming service, and can provide the cloud streaming service to a faster and more users over the same band.

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 still image-based cloud streaming system.
FIG. 4 illustrates a process of capturing a change area in a still image-based cloud streaming service according to an embodiment of the present invention.
5 is a flowchart illustrating a still image-based cloud streaming service method according to an exemplary embodiment of the present invention.
FIG. 6 is a detailed flowchart illustrating a still image-based cloud streaming service method 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.

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.

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

The cloud streaming server 110 receives the cloud streaming service request from the terminal devices 120-1 to 120-N and executes the application. The cloud streaming server 110 transmits the execution result screen corresponding to the application execution result to the terminal devices 120 -1, ..., 120-N.

Since the cloud streaming service basically adopts the cloud streaming technique based on the video codec, even when the cloud streaming technique is applied to a static screen such as a menu display, an inefficient method of capturing an entire screen unnecessarily and encoding it into a video codec We performed cloud streaming service. In order to solve such a problem, the present invention provides a cloud streaming system in which a cloud streaming server detects a change between frames when a change between frames is not large as in a menu display screen, and encodes only the detected change region using a still image compression technique do.

The cloud streaming server 110 captures the change area included in the changed frame as compared with the previous frame. At this time, the changed area compared with the screen area corresponding to the previous frame among the screen areas corresponding to the changed frame can be captured as the changed area. At this time, it is possible to detect a section in which a frame change is small in the entire frame to be transmitted to the terminal devices 120-1, ..., and 120-N, and capture the change area in a section in which the frame change is small. At this time, an event type of an application generated from the terminal devices 120-1, ..., and 120-N may be detected to detect an interval in which a frame change is small.

In addition, the cloud streaming server 110 selects a still image compression scheme in consideration of at least one of the size of the change area and the image property corresponding to the change area, And still image encoding the change area corresponding to the still image. At this time, the change area can be compressed using a still image compression technique of any one of portable network graphics (PNG), portable network graphics (PNG), and joint experts group (JPEG). At this time, if the size of the change area is less than a preset reference value, the change area can be encoded by applying the PNG still image compression technique. At this time, if the size of the change area is equal to or larger than a preset reference value, the still image compression technique can be selected in consideration of image characteristics. In addition, if the image quality is a natural image, the JPEG still image compression technique can be applied to encode the change area. In this case, if the size of the change area is equal to or larger than a preset reference value and the image quality is a synthetic image, the change area can be encoded by applying the palette-edged PNG still image compression technique. At this time, when the image property is an image in which a natural image and a synthetic image are mixed, a region corresponding to the natural image in the change region is compared with a region corresponding to the composite image in the change region, The still image compression technique can be selected according to the nature of the image.

In addition, the cloud streaming server 110 transmits a still image encoded changed area to a user to perform a still image based cloud streaming service.

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

Each of the terminal devices 120-1 to 120-N is connected to a communication network and is capable of executing applications on the basis of a cloud computing system. The terminal devices 120-1 to 120-N are not limited to mobile communication terminals, , A wired terminal, a fixed terminal, and an IP (Internet Protocol) terminal. Each of the terminal devices 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 mobile terminal having various mobile communication specifications such as a tablet PC, a notebook computer, a net book, a personal digital assistant (PDA), a smart TV, have.

The network 130 provides a pathway for transferring data between the cloud streaming server 110 and the terminal devices 120-1, ..., 120-N, . 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. The network used between the cloud streaming server 110 and the terminal devices 120-1 to 120-N in FIG. 1 is a terminal device 120-1 to 120-N, And may be the same or different from the network used for mutual use.

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

Referring to FIG. 2, the cloud streaming server 110 shown in FIG. 1 includes a capture unit 210, an encoding unit 220, a sending unit 230, and a storage unit 240.

Since the cloud streaming service basically adopts the cloud streaming technique based on the video codec, even when the cloud streaming technique is applied to a static screen such as a menu display, an inefficient method of capturing an entire screen unnecessarily and encoding it into a video codec We performed cloud streaming service. In order to solve such a problem, the present invention is characterized in that when a change between frames is not large as in a menu display screen, the cloud streaming server 110 detects a change between frames and encodes only the detected change region using a still image compression technique ).

The capture unit 210 captures a change area included in the changed frame as compared with the previous frame. 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 change between the frames 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 compared with the previous frame, and when displaying on the user's terminal device, And only the change area is changed.

At this time, the changed area compared with the screen area corresponding to the previous frame among the screen areas corresponding to the changed frame can be captured as the changed area. For example, if the changed area compared with the screen area corresponding to the previous frame among the screen areas corresponding to the changed frame is the area A, only the area A of the screen area corresponding to the changed frame can be captured as the changed area. Such a change area may vary in the nature of the image corresponding to the size or change area according to the input signal input from the terminal device of the user.

At this time, a section in which a frame change is small in the entire frame to be transmitted to the user terminal device is detected, and the change area can be captured in a section in which the frame change is small.

At this time, an event type of the application generated from the user's terminal device is detected, and a section in which a frame change is small can be detected. For example, an event type of an application can be determined according to an input signal generated from a user's terminal device. Depending on the input signal, a static event with little frame change or a dynamic event with frequent frame changes such as video playback and game play may occur when an application such as a menu, option, or guide window is executed. Therefore, if the event type is a static event, the user detects an event type with an input signal generated through a terminal device, and can detect an interval in which a frame change is small in the entire frame corresponding to the event.

The encoding unit 220 selects a still image compression scheme considering at least one of the size of the change area and the image property corresponding to the change area, and uses the still image compression scheme to compress the image corresponding to one frame And still image encodes the change area. For example, the change area can be captured in various ways, ranging from a very small size to a large size corresponding to the entire frame size, depending on the area to be changed in the frame. In addition, the image quality of the captured change area may be a natural image such as a photograph or a picture, or a synthetic image formed by combining a plurality of images. In addition, a natural image and a composite image may exist simultaneously in the captured change area.

At this time, the change area can be compressed using a still image compression technique of any one of portable network graphics (PNG), portable network graphics (PNG), and joint experts group (JPEG). In PNG still image compression, the image quality is good when encoding, but when the bandwidth of the transmission network is low due to the large data size, the transmission speed may be lowered. PALETED PNG still image compression techniques can reduce the data size of the image during encoding, which can guarantee the transmission speed, but it can cause deterioration in image quality because it expresses color with 8 bits. The JPEG Still Image Compression technique can greatly reduce the amount of data transferred during encoding because of its high compression efficiency. However, when encoding and decoding are performed, the system load may be increased.

At this time, if the size of the change area is less than a preset reference value, the change area can be encoded by applying the PNG still image compression technique. For example, when the size of the change area is smaller than the preset reference value, the size of the image is not large and the amount of data to be transmitted is not large. Therefore, the PNG still image compression technique, which can relatively encode the image, . In addition, the predetermined reference value can be freely set by the server administrator in consideration of the processing performance of the cloud streaming server 110, the network transmission speed, and the load of the server system.

At this time, if the size of the change area is larger than the reference value, the still image compression technique can be selected in consideration of image properties. If the size of the change area is larger than the reference value and the amount of data to be transmitted is large, encoding can be performed using a JPEG still image compression technique with high compression efficiency or a palettized PNG still image compression technique capable of reducing data size.

At this time, if the image quality is a natural image, the JPEG still image compression technique can be applied to encode the change area. The JPEG still image compression technique may be more effective in compressing a natural image with similar colors gathered around one pixel. Therefore, when the size of the change area is larger than the reference value and the image property corresponding to the change area is a natural image, the change area can be encoded by the JPEG still image compression technique.

In this case, if the size of the change area is equal to or larger than a preset reference value and the image quality is a synthetic image, the change area can be encoded by applying the palette-edged PNG still image compression technique. Since the size of the change area is large, a JPEG still image compression technique with good compression efficiency can be used, but a JPEG still image compression technique can not be expected to have a great effect on a synthetic image. Therefore, in such a case, the change area can be encoded using the paletteed PNG still image compression technique which can reduce the size of the data.

At this time, when the image property is an image in which a natural image and a synthetic image are mixed, a region corresponding to the natural image in the change region is compared with a region corresponding to the composite image in the change region, The still image compression technique can be selected according to the nature of the image. For example, if the area corresponding to the natural image in the change area is larger than the area corresponding to the synthetic image, the change area is encoded by applying the JPEG still image compression technique, and the area corresponding to the synthetic image in the change area is converted into the natural image , The change area can be encoded by applying the palette-edged PNG still image compression technique.

In addition, the order of considering the size of the change area and the image property corresponding to the change area to determine the still image compression technique to encode the change area may be determined differently according to the cloud streaming service.

The sending unit 230 transmits the still image encoded changed area to the user to perform a still image based cloud streaming service. By transmitting the compressed change area to the terminal device of the user by completing the encoding, the user can perform the cloud streaming service so as to receive the feeling of running the application on the terminal device of the user.

The storage unit 240 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 240 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 240 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 include, for example, a hard disk device, an optical disk device, or any other mass storage device.

3 is a diagram illustrating a still image-based cloud streaming system.

Referring to FIG. 3, the server 310 may perform a screen capture by executing a program screen 310 corresponding to a user input generated from a user terminal. In this case, the server 300 may be a server collectively referred to as a cloud streaming server and a web application server. In addition, the process of executing the screen capture by executing the program screen 310 may correspond to the operation flow of the capture unit 210 shown in FIG.

The server 300 may encode the screen 310 of the screen-captured program through a still image compression technique. At this time, the process of performing the encoding (Image Encoding) 320 may correspond to the operation flow of the encoding unit 220 shown in FIG.

At this time, the changed frame can be compared with the previous frame to capture only the changed area. In addition, a still image compression technique such as portable network graphics (PNG), portable network graphics (PNG), and joint experts group (JPEG) is selected in consideration of the size of the changed area and the image characteristics corresponding to the changed area And the changed area can be encoded by the selected still image compression technique.

Thereafter, the server 300 may provide a still image-based cloud streaming service by streaming 330 the still image-encoded changed area to the user's terminal device. At this time, the process of performing the streaming 330 may correspond to the operation flow of the sending unit 230 shown in FIG.

Thereafter, the user's terminal device renders the received data (Image Rendering) 340 so that the program screen 310 executed in the application by the user input (User Input) is displayed to the user Can be displayed.

FIG. 4 illustrates a process of capturing a change area in a still image-based cloud streaming service according to an embodiment of the present invention.

Referring to FIG. 4, a still image-based cloud streaming service according to an embodiment of the present invention can capture and encode only the changed change area 430 by comparing the first frame 410 and the second frame 420.

For example, assuming that the areas of B, C, D and E in the first frame 410 and the second frame 420 are menu displays, in the first frame 410, the cursor is positioned in the C area, B, D, and E regions, and in the second frame 420 the cursor is moved from the C region to the D region so that the D region is shaded so that it can be distinguished from the other B, C, and E regions .

At this time, when the first frame 410 and the second frame 420 are compared, only the changed regions C and D can be captured in the change region 430. Also, the still image compression method may be selected in consideration of the size of the change area 430 and the image characteristics corresponding to the change area 430, and the change area 430 may be encoded using the selected still image compression technique.

Thus, in the conventional cloud streaming service, the first frame 410 and the second frame 420 must be clearly changed. In the conventional cloud streaming service, it is necessary to capture and encode all the frames corresponding to the frame rate including two frames have. However, since the still image-based cloud streaming service captures only the change area 430 and encodes it using the still image compression technique, it improves service efficiency compared to the existing cloud streaming service method that captures an entire screen of unnecessary frames and frames .

5 is a flowchart illustrating a still image-based cloud streaming service method according to an exemplary embodiment of the present invention.

Referring to FIG. 5, a still image-based cloud streaming service method according to an exemplary embodiment of the present invention captures a change area included in a changed frame compared with a previous frame (S510). 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 change between the frames 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 compared with the previous frame, and when displaying on the user's terminal device, And only the change area is changed.

At this time, the changed area compared with the screen area corresponding to the previous frame among the screen areas corresponding to the changed frame can be captured as the changed area. For example, if the changed area compared with the screen area corresponding to the previous frame among the screen areas corresponding to the changed frame is the area A, only the area A of the screen area corresponding to the changed frame can be captured as the changed area. Such a change area may vary in the nature of the image corresponding to the size or change area according to the input signal input from the terminal device of the user.

At this time, a section in which a frame change is small in the entire frame to be transmitted to the user terminal device is detected, and the change area can be captured in a section in which the frame change is small.

At this time, an event type of the application generated from the user's terminal device is detected, and a section in which a frame change is small can be detected. For example, an event type of an application can be determined according to an input signal generated from a user's terminal device. Depending on the input signal, a static event with little frame change or a dynamic event with frequent frame changes such as video playback and game play may occur when an application such as a menu, option, or guide window is executed. Therefore, if the event type is a static event, the user detects an event type with an input signal generated through a terminal device, and can detect an interval in which a frame change is small in the entire frame corresponding to the event.

Also, the still image-based cloud streaming service method according to an embodiment of the present invention selects a still image compression scheme considering at least one of a size of a change area and an image property corresponding to a change area, Still image encoding is performed on the change area corresponding to one frame using the image compression technique (S520). For example, the change area can be captured in various ways, ranging from a very small size to a large size corresponding to the entire frame size, depending on the area to be changed in the frame. In addition, the image quality of the captured change area may be a natural image such as a photograph or a picture, or a synthetic image formed by combining a plurality of images. In addition, a natural image and a composite image may exist simultaneously in the captured change area.

At this time, the change area can be compressed using a still image compression technique of any one of portable network graphics (PNG), portable network graphics (PNG), and joint experts group (JPEG). In PNG still image compression, the image quality is good when encoding, but when the bandwidth of the transmission network is low due to the large data size, the transmission speed may be lowered. PALETED PNG still image compression techniques can reduce the data size of the image during encoding, which can guarantee the transmission speed, but it can cause deterioration in image quality because it expresses color with 8 bits. The JPEG Still Image Compression technique can greatly reduce the amount of data transferred during encoding because of its high compression efficiency. However, when encoding and decoding are performed, the system load may be increased.

At this time, if the size of the change area is less than a preset reference value, the change area can be encoded by applying the PNG still image compression technique. For example, when the size of the change area is smaller than the preset reference value, the size of the image is not large and the amount of data to be transmitted is not large. Therefore, the PNG still image compression technique, which can relatively encode the image, . Also, the predetermined reference value can be freely set by the server administrator in consideration of the processing performance of the cloud streaming server, the network transmission speed, the load of the server system, and the like.

At this time, if the size of the change area is larger than the reference value, the still image compression technique can be selected in consideration of image properties. If the size of the change area is larger than the reference value and the amount of data to be transmitted is large, encoding can be performed using a JPEG still image compression technique with high compression efficiency or a palettized PNG still image compression technique capable of reducing data size.

At this time, if the image quality is a natural image, the JPEG still image compression technique can be applied to encode the change area. The JPEG still image compression technique may be more effective in compressing a natural image with similar colors gathered around one pixel. Therefore, when the size of the change area is larger than the reference value and the image property corresponding to the change area is a natural image, the change area can be encoded by the JPEG still image compression technique.

In this case, if the size of the change area is equal to or larger than a preset reference value and the image quality is a synthetic image, the change area can be encoded by applying the palette-edged PNG still image compression technique. Since the size of the change area is large, a JPEG still image compression technique with good compression efficiency can be used, but a JPEG still image compression technique can not be expected to have a great effect on a synthetic image. Therefore, in such a case, the change area can be encoded using the paletteed PNG still image compression technique which can reduce the size of the data.

At this time, when the image property is an image in which a natural image and a synthetic image are mixed, a region corresponding to the natural image in the change region is compared with a region corresponding to the composite image in the change region, The still image compression technique can be selected according to the nature of the image. For example, if the area corresponding to the natural image in the change area is larger than the area corresponding to the synthetic image, the change area is encoded by applying the JPEG still image compression technique, and the area corresponding to the synthetic image in the change area is converted into the natural image , The change area can be encoded by applying the palette-edged PNG still image compression technique.

In addition, the order of considering the size of the change area and the image property corresponding to the change area to determine the still image compression technique to encode the change area may be determined differently according to the cloud streaming service.

In addition, the still image-based cloud streaming service method according to an embodiment of the present invention transmits a still image encoded changed region to a user to perform a still image based cloud streaming service in operation S530. A still image encoding and transmitting the compressed change area to a terminal device of a user enables a user to perform a cloud streaming service so as to receive an impression that an application is executed on the terminal device.

FIG. 6 is a detailed flowchart illustrating a still image-based cloud streaming service method according to an embodiment of the present invention.

Referring to FIG. 6, in the still image-based cloud streaming service method according to an embodiment of the present invention, a cloud streaming server captures a change area included in a changed frame compared with a previous frame in operation S610. At this time, the changed area compared with the screen area corresponding to the previous frame among the screen areas corresponding to the changed frame can be captured as the changed area. At this time, a section in which a frame change is small in the entire frame to be transmitted to the user terminal device is detected, and the change area can be captured in a section in which the frame change is small. At this time, an event type of the application generated from the user's terminal device is detected, and a section in which a frame change is small can be detected.

The cloud streaming server determines whether the size of the change area is less than a preset reference value (S615).

If it is determined in step S615 that the size of the change area is less than the preset reference value, the change area is encoded using the PNG still image compression technique (S620). In PNG still image compression, the image quality is good when encoding, but when the bandwidth of the transmission network is low due to the large data size, the transmission speed may be lowered. Therefore, since the size of the image of the change area is not large and the amount of data to be transmitted is not large, the PNG still image compression technique, which can relatively encode the image, can be applied.

If it is determined in step S615 that the size of the change area is equal to or greater than the predetermined reference value, it is determined whether the image property corresponding to the change area is a natural image (S625).

If it is determined in step S625 that the image property corresponding to the change area is the natural image, the change area is encoded using the JPEG still image compression technique (S630). The JPEG Still Image Compression technique can greatly reduce the amount of data transferred during encoding because of its high compression efficiency. However, when encoding and decoding are performed, the system load may be increased. In addition, the JPEG still image compression technique may be more effective in compressing a natural image in which similar colors are gathered around one pixel rather than a composite image in which a plurality of pictures or photographs are combined. Therefore, when the size of the change area is larger than the reference value and the image property corresponding to the change area is a natural image, the change area can be encoded by the JPEG still image compression technique.

If it is determined in step S625 that the image property corresponding to the change area is a composite image, the change area is encoded using the palette-based PNG still image compression technique (S640). If the size of the change area is larger than the reference value and the image property corresponding to the change area is a synthetic image, the change area can be encoded using the palette-based PNG still image compression technique, which can reduce the data size .

Thereafter, the cloud streaming server delivers the still image encoded changed area to the user (S650). A still image encoding and transmitting the compressed change area to a terminal device of a user enables a user to perform a cloud streaming service so as to receive an impression that an application is executed on the terminal device.

The still image based cloud streaming service method according to the present invention may 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 configured 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 still image-based cloud streaming service method, and the apparatus therefor according to the present invention are not limited to the configuration and method of the embodiments described above, All or some of the embodiments may be selectively combined so that various modifications can be made.

According to the present invention, it is possible to capture a change area included in a changed frame compared with a previous frame, select a still image compression technique considering at least one of the size of the change area and the image property corresponding to the change area, A still image corresponding to one frame is still image encoded using a compression technique, and a still image encoded changed region is transmitted to a user to perform a still image based cloud streaming service. Furthermore, cloud-streaming service providers can maximize streaming compression efficiency through still-image-based cloud streaming services and provide cloud streaming services to users faster and through more users over the same band. Thereby providing efficient services to users.

110: Cloud streaming servers 120-1 to 120-N:
130: Network 210: Capture unit
220: encoding unit 230:
240: Storage unit 300: Server
310: Program screen 320: Image encoding
330: Streaming 340: Image rendering
410: first frame 420: second frame
430: Change area

Claims (20)

A capturing unit for capturing a change area included in the changed frame in comparison with the previous frame;
Selecting a still image compression scheme considering at least one of a size of the change area and an image property corresponding to the change area, and using the still image compression scheme, An encoding unit encoding a still image; And
And transmits the still image-encoded change region to the user to perform a still image based cloud streaming service.
Wherein the server comprises: The method according to claim 1,
The encoding unit
Wherein the change area is compressed using a still image compression technique of any one of portable network graphics (PNG), portable network graphics (PNG), and joint art experts group (JPEG). The method of claim 2,
The encoding unit
Wherein when the size of the change area is less than a predetermined reference value, the change area is encoded by applying the PNG still image compression scheme. The method of claim 3,
The encoding unit
Wherein the still image compression technique is selected in consideration of the image quality when the size of the change area is greater than or equal to the reference value. The method of claim 2,
The encoding unit
Wherein when the image quality is a natural image, the change area is encoded by applying the JPEG still image compression technique. The method of claim 5,
The encoding unit
Wherein the change region is encoded by applying the palette PNG still image compression scheme when the size of the change region is equal to or greater than a preset reference value and the image property is a synthetic image. The method of claim 6,
The encoding unit
Wherein when the image property is an image in which the natural image and the synthetic image are mixed, an area corresponding to the natural image of the change area is compared with an area corresponding to the synthetic image of the change area, Wherein the still image compression technique is selected according to image properties corresponding to the region. The method according to claim 1,
The capture unit
Wherein the control unit captures the changed area in comparison with the screen area corresponding to the previous frame among the screen areas corresponding to the changed frame as the change area. The method of claim 8,
The capture unit
Wherein the frame detecting unit detects an interval in which a frame change is small among the entire frame to be transmitted to the terminal apparatus of the user and captures the change area in a section in which the frame change is small. The method of claim 9,
The capture unit
Detects an event type of an application generated from the terminal device of the user, and detects an interval in which the frame change is small. Capturing a change area included in a changed frame compared to a previous frame;
Selecting a still image compression scheme considering at least one of a size of the change area and an image property corresponding to the change area, and using the still image compression scheme, Encoding a still image; And
Transmitting the still image encoded change area to the user to perform a still image based cloud streaming service
The method of claim 1, further comprising the steps of: The method of claim 11,
The encoding step
A still image of the cloud streaming service is compressed using a still image compression technique of PNG (Portable Network Graphics), Palletized PNG (Portable Network Graphics), and JPEG (Joint Pictures Experts Group) Based cloud streaming service method. The method of claim 12,
The encoding step
And if the size of the change area is less than a preset reference value, encoding the change area by applying the PNG still image compression scheme to the still image based cloud streaming service method of the cloud streaming service. 14. The method of claim 13,
The encoding step
Wherein the still image compression technique is selected in consideration of the image property when the size of the change area is greater than or equal to the reference value. The method of claim 12,
The encoding step
Wherein the JPEG still image compression technique is applied to encode the change area when the image quality is a natural image. 16. The method of claim 15,
The encoding step
Wherein the change area is encoded by applying the palette PNG still image compression scheme when the size of the change area is equal to or greater than a preset reference value and the image property is a synthetic image. Image based cloud streaming service method. 18. The method of claim 16,
The encoding step
Wherein when the image property is an image in which the natural image and the synthetic image are mixed, an area corresponding to the natural image of the change area is compared with an area corresponding to the synthetic image of the change area, Wherein the still image compression technique is selected according to an image characteristic corresponding to a region of the still image. The method of claim 11,
The step of capturing
Wherein the change area is captured by the change area in comparison with a screen area corresponding to the previous frame among the screen areas corresponding to the changed frame. A computer program stored on a medium for carrying out the method according to any one of claims 11 to 18. Capturing a change area included in a changed frame in comparison with a previous frame, selecting a still image compression scheme considering at least one of a size of the change area and an image property corresponding to the change area, A cloud streaming server for still image encoding the change region corresponding to one frame using a still image compression scheme and transmitting the still image encoded change region to the user to perform a still image based cloud streaming service; And
And a terminal for receiving an application execution result screen corresponding to the cloud streaming service from the cloud streaming server,
And a server for providing the cloud streaming service.

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