KR102199270B1 - System for cloud streaming service, method of cloud streaming service based on still image and apparatus for the same - Google Patents

Abstract

Disclosed are a cloud streaming service system, a still image-based cloud streaming service method, and an apparatus therefor. Compared with the previous frame, the change region included in the changed frame is captured, the still image compression method is selected in consideration of one or more of the size of the change region and the image property, and the change region encoded by the still image compression method is presented to the user. By transmitting, it is possible to perform a still image-based cloud streaming service. When providing a still image-based cloud streaming service, it is possible to improve the compression efficiency of still images and the speed of the cloud streaming service by using a still image compression technique suitable for the situation.

Description

Cloud streaming service system, still image-based cloud streaming service method and device therefor {SYSTEM FOR CLOUD STREAMING SERVICE, METHOD OF CLOUD STREAMING SERVICE BASED ON STILL IMAGE AND APPARATUS FOR THE SAME}

The present invention is a cloud streaming service capable of improving compression efficiency and service speed by selecting and encoding a compression technique according to a captured screen when providing a still image-based cloud streaming service for a portion with little change in the cloud streaming service. A 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 individuals has rapidly improved. With this increase in communication speed, access to a remote computer to download or upload large amounts of data, or log in locally to the remote computer using a remote computer control program. As previously described, an environment where remote computers can be used has been created.

In addition, the application is run on the server, the driving screen is compressed through video encoding and transmitted to the client, and the client plays the transmitted video to create the same effect as running the application on its own terminal based on screen virtualization. Cloud streaming service is in the spotlight.

In this cloud streaming service, a cloud streaming technique based on a video codec is basically applied. However, even in the case of servicing a static screen such as a menu display, since the entire screen is unnecessarily captured and operated using a video codec, there is an inefficient part in operating the cloud streaming service system.

Korean Patent Publication No. 10-2014-0076668, published on June 23, 2013 (Name: Cloud streaming-based game provision method, system, client terminal and service device)

An object of the present invention is to improve compression efficiency and cloud streaming service speed by using a still image compression technique suitable for a situation when providing a still image-based cloud streaming service.

In addition, an object of the present invention is to maximize the streaming extrusion efficiency through a still image-based cloud streaming service to provide a cloud streaming service that is faster and targets more users through the same band.

Cloud streaming server according to the present invention for achieving the above object, the capture unit for capturing a change area included in the changed frame compared to the previous frame; A still image compression technique is selected in consideration of any one or more of the size of the change area and image properties corresponding to the change area, and the change area corresponding to one frame by using the still image compression technique. An encoding unit for encoding a still image; And a sending unit that transmits the still image-encoded change area to the user to perform a still image-based cloud streaming service.

In this case, the encoding unit may compress the change region using any one of still image compression techniques among portable network graphics (PNG), portable network graphics (PNG), and joint photography experts group (JPEG).

In this case, when the size of the change region is less than a preset reference value, the encoding unit may encode the change region by applying the PNG still image compression technique.

In this case, when the size of the change region is greater than or equal to the reference value, the encoding unit may select the still image compression technique in consideration of the image property.

In this case, when the image property is a natural image, the encoding unit may encode the change region by applying the JPEG still image compression technique.

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

In this case, when the image property is an image in which the natural image and the synthetic image are mixed, the encoding unit includes a region corresponding to the natural image among the change regions and a region corresponding to the composite image among the change regions. The still image compression technique can be selected according to image properties corresponding to more areas by comparing.

In this case, the capture unit may capture a changed area as the change area compared to a screen area corresponding to the previous frame among the screen areas corresponding to the changed frame.

In this case, the capture unit may detect a section in which a frame change is small among the entire frame section to be transmitted to the user's terminal device, and capture the change area in the section in which the frame change is small.

In this case, the capture unit may detect an event type of an application generated from the user's terminal device to detect a section in which the frame change is small.

In addition, a still image-based cloud streaming service method according to the present invention includes: capturing a change area included in a changed frame compared to a previous frame; A still image compression technique is selected in consideration of any one or more of the size of the change area and image properties corresponding to the change area, and the change area corresponding to one frame by using the still image compression technique. Encoding the still image; And transmitting the still image-encoded change region to the user to perform a still image-based cloud streaming service.

In this case, the encoding step may compress the change region using any one of still image compression techniques among portable network graphics (PNG), portable network graphics (PNG), and joint photography experts group (JPEG).

In this case, in the encoding step, when the size of the change region is less than a preset reference value, the change region may be encoded by applying the PNG still image compression technique.

In this case, in the encoding step, when the size of the change region is greater than or equal to the reference value, the still image compression technique may be selected in consideration of the image property.

In this case, in the encoding step, when the image property is a natural image, the change region may be encoded by applying the JPEG still image compression technique.

In this case, in the encoding step, when the size of the change region is greater than or equal to a preset reference value, and the image property is a synthetic image, the change region may be encoded by applying the palletized PNG still image compression technique. .

In this case, the encoding step is, 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 among the change regions and the composite image among the change regions. The still image compression technique may be selected according to image properties corresponding to more areas by comparing the areas to be compared.

In this case, in the capturing step, the changed area may be captured as the change area by comparing 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 a section in which a frame change is small among the entire frame section to be transmitted to the user's terminal device, and the change region may be captured in a section in which the frame change is small.

In this case, in the detecting step, an event type of an application generated from the user's terminal device may be detected and a section in which the frame change is small may be detected.

In addition, as another means for solving the problem of the present invention, a computer program stored in a medium is provided in order to execute the above-described method.

In addition, the cloud streaming service system according to the present invention captures the change region included in the changed frame compared to the previous frame, and considers any one or more of the size of the change region and the image property corresponding to the change region. Selecting a (still image) compression technique, encoding the change area corresponding to one frame using the still image compression technique, and transmitting the still image-encoded change area to the user A cloud streaming server that performs 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, when providing a still image-based cloud streaming service, it is possible to improve image compression efficiency and cloud streaming service speed by using a still image compression technique suitable for a situation.

In addition, the present invention maximizes the streaming compression efficiency through a still image-based cloud streaming service, thereby providing a cloud streaming service faster and targeting more users through the same band.

1 is a block diagram showing a cloud streaming service system according to an embodiment of the present invention.
2 is a block diagram illustrating an example of a cloud streaming server shown in FIG. 1.
3 is a diagram showing a still image-based cloud streaming system.
4 is a diagram illustrating 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 embodiment of the present invention.
6 is a detailed operation 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. However, in the following description and the accompanying drawings, detailed descriptions of known functions or configurations that may obscure the subject matter of the present invention will be omitted. In addition, it should be noted that the same components are indicated by the same reference numerals as possible throughout the drawings.

The terms or words used in the present specification and claims described below should not be construed as being limited to a conventional or dictionary meaning, and the inventor is appropriate as a concept of terms for describing his own invention in the best way. It should be interpreted as a meaning and concept consistent with the technical idea of the present invention on the basis of the principle that it can be defined. Therefore, the embodiments described in the present specification and the configurations shown in the drawings are only the most preferred embodiments of the present invention, and do not represent all the technical spirit of the present invention, and thus various alternatives that can be substituted for them at the time of application It should be understood that there may be equivalents and variations. In addition, terms such as first and second are used to describe various elements, and are used only for the purpose of distinguishing one element from other elements, and are not used to limit the elements.

1 is a block diagram showing 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, terminal devices 120-1, ..., 120-N, and a network 130. .

The cloud streaming server 110 executes an application by receiving a cloud streaming service request from the terminal devices 120-1, ..., 120-N, and displays an execution result screen corresponding to the application execution result to the terminal devices 120 -1, ..., 120-N).

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

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

In addition, the cloud streaming server 110 selects a still image compression technique in consideration of any one or more of the size of the change area and image properties corresponding to the change area, and uses the still image compression technique to select one frame. The still image is encoded on the change area corresponding to. In this case, the change region may be compressed using any one of still image compression techniques among portable network graphics (PNG), portable network graphics (PNG), and joint photography experts group (JPEG). In this case, when the size of the change region is less than a preset reference value, the change region may be encoded by applying a PNG still image compression technique. In this case, when the size of the change region is greater than or equal to a preset reference value, a still image compression technique may be selected in consideration of image properties. In addition, when the image property is a natural image, the change region may be encoded by applying a JPEG still image compression technique. In this case, when the size of the change region is greater than or equal to a preset reference value and the image property is a synthetic image, the change region may be encoded by applying a palletized PNG still image compression technique. In this case, when the image property is an image in which a natural image and a synthetic image are mixed, the area corresponding to the natural image among the change areas and the area corresponding to the composite image among the change areas are compared to correspond to more areas. You can choose a still image compression technique according to the image properties.

In addition, the cloud streaming server 110 performs a still image-based cloud streaming service by transmitting the still image-encoded change region to the user.

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

Terminal devices 120-1, ..., 120-N are devices that are connected to a communication network and can execute applications based on a cloud computing system, and are not limited to mobile communication terminals, and all information and communication devices and multimedia terminals , A wired terminal, a fixed terminal, and an Internet Protocol (IP) terminal. In addition, the terminal devices 120-1, ..., 120-N are mobile phones, Portable Multimedia Played (PMP), Mobile Internet Devices (MID), smart phones, desktops, and tablet computers, respectively. (Tablet PC), notebook (Note book), net book (Net Book), personal digital assistant (PDA), smart TV and information communication devices, such as a mobile terminal with various mobile communication specifications have.

The network 130 provides a path for transferring data between the cloud streaming server 110 and the terminal devices 120-1, ..., 120-N, and is a network used in the past and a network that can be developed in the future. It is a concept that encompasses all. For example, the network 130 is a wired/wireless local area communication network that provides communication of various information devices within a limited area, a mobile communication network that provides communication between mobiles and the mobile and the outside of the mobile, and the earth station and the earth station communicate using satellites. It may be a satellite communication network, a wired or wireless communication network, or a combination of two or more. Meanwhile, the transmission method standard of the network 130 is not limited to the existing transmission method standard, and may include all transmission method standards to be developed in the future. In addition, in FIG. 1, a network used between the cloud streaming server 110 and the terminal devices 120-1, ..., 120-N is the terminal devices 120-1, ..., 120-N. It may be different from a network used for each other, or may be the same.

2 is a block diagram illustrating an example of a cloud streaming server shown in FIG. 1.

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

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

The capture unit 210 captures a change area included in the changed frame compared to the previous frame. The video codec-based cloud streaming technique can perform encoding by capturing all frames corresponding to the screen on which the application is running. However, if there is not much change between frames on the screen on which the application is running, the still image encoding is performed by capturing only the change region of the changed frame compared to the previous frame, and the part except the change region is the same when displayed on the user's terminal device It can be displayed in such a way that it is displayed in a way that changes only the change area.

In this case, among the screen areas corresponding to the changed frame, the changed area may be captured as the change area compared with the screen area corresponding to the previous frame. For example, if the area A is the changed area compared to the screen area corresponding to the previous frame among the screen area corresponding to the changed frame, only the area A of the screen area corresponding to the changed frame may be captured as the change area. The change region may vary in size or image properties corresponding to the change region according to an input signal input from the user's terminal device.

In this case, a section in which a frame change is small among the entire frame section to be transmitted to the user's terminal device may be detected, and a change region may be captured in a section in which the frame change is small.

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

The encoding unit 220 selects a still image compression technique in consideration of any one or more of the size of the change area and the image properties corresponding to the change area, and uses the still image compression technique to correspond to one frame. Encode the region of change as a still image. For example, the change area may be variously captured from a very small size to a large size corresponding to the total size of the frame according to the area changed in the frame. In addition, the image property of the captured change area may be a natural image such as a photograph or a picture, or a synthetic image created by combining multiple images. In addition, a natural image and a composite image may exist simultaneously in the captured change area.

In this case, the change region may be compressed using any one of still image compression techniques among portable network graphics (PNG), portable network graphics (PNG), and joint photography experts group (JPEG). In the PNG still image compression technique, the image quality is good when encoding, but the transmission speed may decrease when the bandwidth of the transmission network is low due to the large data size. The palletized PNG still image compression technique reduces the data size of the image during encoding, so the transmission speed can be guaranteed. However, since the color is expressed in 8 bits, it may deteriorate the image quality. The JPEG still image compression technique has good compression efficiency and can significantly reduce the amount of transmitted data during encoding, but as the compression efficiency is high, it can generate a lot of system load when encoding and decoding are performed.

In this case, when the size of the change region is less than a preset reference value, the change region may be encoded by applying a PNG still image compression technique. For example, if 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, a PNG still image compression technique that can be encoded with relatively high quality is applied to encode the image. I can. In addition, the preset reference value may 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 server system load.

In this case, when the size of the change area is greater than or equal to the reference value, a still image compression technique may be selected in consideration of image properties. When the amount of data to be transmitted is large because the size of the change region is greater than or equal to the reference value, encoding may be performed using a JPEG still image compression technique with good compression efficiency during encoding or a palletized PNG still image compression technique capable of reducing data size.

In this case, when the image property is a natural image, the change region may be encoded by applying a JPEG still image compression technique. The JPEG still image compression technique may be more effective when compressing natural images in which similar colors are gathered around one pixel. Accordingly, when the size of the change region is larger than the reference value and the image property corresponding to the change region is a natural image, the change region may be encoded using a JPEG still image compression technique.

In this case, when the size of the change region is greater than or equal to a preset reference value and the image property is a synthetic image, the change region may be encoded by applying a palletized 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 for a composite image, it may be difficult to expect a large effect even with the JPEG still image compression technique. Therefore, in this case, the change region can be encoded using a palletized PNG still image compression technique that can reduce the size of the data.

In this case, when the image property is an image in which a natural image and a synthetic image are mixed, the area corresponding to the natural image among the change areas and the area corresponding to the composite image among the change areas are compared to correspond to more areas. You can choose a still image compression technique according to the image properties. For example, if the area corresponding to the natural image among the change areas is larger than the area corresponding to the composite image, a JPEG still image compression technique is applied to encode the change area, and the area corresponding to the composite image among the change areas is a natural image. If there are more areas than the area corresponding to, the change area can be encoded by applying a palletized PNG still image compression technique.

In addition, in order to determine a still image compression technique for encoding the change region, the order of considering the size of the change region and the image properties corresponding to the change region may be determined differently according to the cloud streaming service.

The sending unit 230 transmits the still image-encoded change region to the user to perform a still image-based cloud streaming service. By completing the encoding and transmitting the compressed change region to the user's terminal device, a cloud streaming service can be performed so that the user's terminal device can feel the application being executed.

As described above, the storage unit 240 stores various types of information generated during a cloud streaming service process according to an embodiment of the present invention.

According to an embodiment, the storage unit 240 may be configured independently from the cloud streaming server 110 to support a function for a cloud streaming service. In this case, the storage unit 240 may operate as a separate mass storage, and may include a control function for performing the operation.

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

Meanwhile, the cloud streaming server 110 is equipped with a memory to store information in the device. In one implementation, the memory is a computer-readable medium. In one implementation, the memory may be a volatile memory unit, and in another implementation, 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 some other mass storage device.

3 is a diagram showing 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's terminal device. 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, a process of performing a screen capture by executing the program screen 310 may correspond to an operation flow of the capture unit 210 illustrated in FIG. 2.

The server 300 may encode (Image Encoding) 320 the captured program screen 310 through a still image compression technique. In this case, the process of performing the encoding (Image Encoding) 320 may correspond to the operation flow of the encoding unit 220 illustrated in FIG. 2.

In this case, only the changed area may be captured by comparing the changed frame with the previous frame. In addition, considering the size of the changed area and image properties corresponding to the changed area, a still image compression technique is selected from among PNG (portable network graphics), palletized PNG (portable network graphics), and JPEG (joint photography experts group). And, it is possible to encode the changed area using the selected still image compression technique.

Thereafter, the server 300 may provide a still image-based cloud streaming service by streaming 330 of the changed region encoded with the still image to the user's terminal device. In this case, the process of performing the streaming 330 may correspond to the operation flow of the sending unit 230 shown in FIG. 2.

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 is sent to the user as if it was executed on the user's terminal device. Can be displayed.

4 is a diagram illustrating 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, the still image-based cloud streaming service according to an embodiment of the present invention may compare a first frame 410 and a second frame 420 to capture and encode only a changed region 430.

For example, assuming that the areas 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, so that the C area is different. It has been shaded so that it can be distinguished from areas B, D, and E, and in the second frame 420, the cursor moves from area C to area D, so that area D is shaded so that it can be distinguished from other areas B, C and E. I can.

In this case, when comparing the first frame 410 and the second frame 420, only the changed regions C and D regions may be captured as the change region 430. In addition, a still image compression technique may be selected in consideration of the size of the change area 430 and image properties corresponding to the change area 430, and the change area 430 may be encoded using the selected still image compression technique.

As described above, the first frame 410 and the second frame 420 are frames that are clearly changed, and in the case of the existing cloud streaming service, it may be necessary to capture all frames corresponding to the frame rate including two frames to perform encoding. have. However, since the still image-based cloud streaming service captures only the change area 430 and encodes it using a still image compression technique, it will improve the efficiency of the service compared to the existing cloud streaming service method that captures unnecessary many frames and the entire screen. I can.

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

Referring to FIG. 5, the still image-based cloud streaming service method according to an embodiment of the present invention captures a change area included in a changed frame compared to a previous frame (S510). The video codec-based cloud streaming technique can perform encoding by capturing all frames corresponding to the screen on which the application is running. However, if there is not much change between frames on the screen on which the application is running, the still image encoding is performed by capturing only the change region of the changed frame compared to the previous frame, and the part except the change region is the same when displayed on the user's terminal device It can be displayed in such a way that it is displayed in a way that changes only the change area.

In this case, among the screen areas corresponding to the changed frame, the changed area may be captured as the change area compared with the screen area corresponding to the previous frame. For example, if the area A is the changed area compared to the screen area corresponding to the previous frame among the screen area corresponding to the changed frame, only the area A of the screen area corresponding to the changed frame may be captured as the change area. The change region may vary in size or image properties corresponding to the change region according to an input signal input from the user's terminal device.

In this case, a section in which a frame change is small among the entire frame section to be transmitted to the user's terminal device may be detected, and a change region may be captured in a section in which the frame change is small.

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

In addition, the still image-based cloud streaming service method according to an embodiment of the present invention selects a still image compression technique in consideration of at least one of a size of a change area and an image property corresponding to the change area, and A still image is encoded on a change area corresponding to one frame using an image compression technique (S520). For example, the change area may be variously captured from a very small size to a large size corresponding to the total size of the frame according to the area changed in the frame. In addition, the image property of the captured change area may be a natural image such as a photograph or a picture, or a synthetic image created by combining multiple images. In addition, a natural image and a composite image may exist simultaneously in the captured change area.

In this case, the change region may be compressed using any one of still image compression techniques among portable network graphics (PNG), portable network graphics (PNG), and joint photography experts group (JPEG). In the PNG still image compression technique, the image quality is good when encoding, but the transmission speed may decrease when the bandwidth of the transmission network is low due to the large data size. The palletized PNG still image compression technique reduces the data size of the image during encoding, so the transmission speed can be guaranteed. However, since the color is expressed in 8 bits, it may deteriorate the image quality. The JPEG still image compression technique has good compression efficiency and can significantly reduce the amount of transmitted data during encoding, but as the compression efficiency is high, it can generate a lot of system load when encoding and decoding are performed.

In this case, when the size of the change region is less than a preset reference value, the change region may be encoded by applying a PNG still image compression technique. For example, if 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, a PNG still image compression technique that can be encoded with relatively high quality is applied to encode the image. I can. In addition, the preset reference value may be freely set by the server administrator in consideration of the processing performance of the cloud streaming server, the network transmission speed, and the server system load.

In this case, when the size of the change area is greater than or equal to the reference value, a still image compression technique may be selected in consideration of image properties. When the amount of data to be transmitted is large because the size of the change region is greater than or equal to the reference value, encoding may be performed using a JPEG still image compression technique with good compression efficiency during encoding or a palletized PNG still image compression technique capable of reducing data size.

In this case, when the image property is a natural image, the change region may be encoded by applying a JPEG still image compression technique. The JPEG still image compression technique may be more effective when compressing natural images in which similar colors are gathered around one pixel. Accordingly, when the size of the change region is larger than the reference value and the image property corresponding to the change region is a natural image, the change region may be encoded using a JPEG still image compression technique.

In this case, when the size of the change region is greater than or equal to a preset reference value and the image property is a synthetic image, the change region may be encoded by applying a palletized 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 for a composite image, it may be difficult to expect a large effect even with the JPEG still image compression technique. Therefore, in this case, the change region can be encoded using a palletized PNG still image compression technique that can reduce the size of the data.

In this case, when the image property is an image in which a natural image and a synthetic image are mixed, the area corresponding to the natural image among the change areas and the area corresponding to the composite image among the change areas are compared to correspond to more areas. You can choose a still image compression technique according to the image properties. For example, if the area corresponding to the natural image among the change areas is larger than the area corresponding to the composite image, a JPEG still image compression technique is applied to encode the change area, and the area corresponding to the composite image among the change areas is a natural image. If there are more areas than the area corresponding to, the change area can be encoded by applying a palletized PNG still image compression technique.

In addition, in order to determine a still image compression technique for encoding the change region, the order of considering the size of the change region and the image properties corresponding to the change region 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 performs a still image-based cloud streaming service by transmitting a still image-encoded change region to a user (S530). A cloud streaming service can be performed so that the user's terminal device can feel the application running on the user's terminal device by transmitting the compressed change region by encoding the still image to the user's terminal device.

6 is a detailed operation 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 first captures a change area included in a changed frame compared to a previous frame (S610). In this case, among the screen areas corresponding to the changed frame, the changed area may be captured as the change area compared with the screen area corresponding to the previous frame. In this case, a section in which a frame change is small among the entire frame section to be transmitted to the user's terminal device may be detected, and a change region may be captured in a section in which the frame change is small. In this case, by detecting an event type of an application generated from the user's terminal device, a section with little change in frame may be detected.

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

As a result of the determination in step S615, if the size of the change region is less than a preset reference value, the change region is encoded using a PNG still image compression technique (S620). In the PNG still image compression technique, the image quality is good when encoding, but the transmission speed may decrease when the bandwidth of the transmission network is low due to the large data size. Therefore, since the size of the image in 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 be encoded with relatively high quality, can be applied to encode the image.

As a result of the determination in step S615, if the size of the change region is greater than or equal to a preset reference value, it is determined whether the image property corresponding to the change region is a natural image (S625).

As a result of the determination in step S625, if the image property corresponding to the change region is a natural image, the change region is encoded using a JPEG still image compression technique (S630). The JPEG still image compression technique has good compression efficiency and can significantly reduce the amount of transmitted data during encoding, but as the compression efficiency is high, it can generate a lot of system load when encoding and decoding are performed. In addition, the JPEG still image compression technique may be more effective when compressing natural images in which similar colors are gathered around one pixel than when a composite image of several pictures or photos is compressed. Accordingly, when the size of the change region is larger than the reference value and the image property corresponding to the change region is a natural image, the change region may be encoded using a JPEG still image compression technique.

As a result of the determination in step S625, if the image property corresponding to the change region is a composite image, the change region is encoded using a palletized PNG still image compression technique (S640). When 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 a palletized PNG still image compression technique that can reduce the size of the data. .

After that, the cloud streaming server delivers the still image-encoded change area to the user (S650). A cloud streaming service can be performed so that the user's terminal device can feel the application running on the user's terminal device by transmitting the compressed change region by encoding the still image to the user's 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 that 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 specially designed and configured for the present invention, or may be known and usable to those skilled in computer software. Examples of computer-readable recording media include magnetic media such as hard disks, floppy disks, and magnetic tapes, optical media such as CD-ROMs and DVDs, and magnetic media such as floptical disks. -Including magneto-optical media, and any type of hardware device specially configured to store and execute program instructions such as ROM, RAM, flash memory, etc. Examples of the program instructions may include not only machine language codes such as those produced by a compiler but also high-level language codes that can be executed by a computer using an interpreter or the like. These hardware devices may be configured to operate as one or more software modules to perform the operation 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 for the same according to the present invention are not limited to the configuration and method of the embodiments described as described above, but the embodiments are All or some of the embodiments may be selectively combined and configured so that various modifications may be made.

According to the present invention, a change region included in a frame changed compared to a previous frame is captured, a still image compression technique is selected in consideration of any one or more of the size of the change region and image properties corresponding to the change region, and the selected still image A still image-based cloud streaming service may be performed by encoding a still image on a change area corresponding to one frame using a compression technique, and transmitting the still image-encoded change area to a user. Furthermore, cloud streaming service providers can save resources that require bandwidth expansion because they can maximize streaming compression efficiency through still image-based cloud streaming services and provide cloud streaming services faster and target more users through the same band. While doing so, it can provide efficient services to users.

110: cloud streaming server 120-1 to 120-N: terminal devices
130: network 210: capture unit
220: encoding unit 230: sending unit
240: storage unit 300: server
310: Program Screen 320: Image Encoding
330: streaming 340: image rendering
410: first frame 420: second frame
430: area of change

Claims (20)

A capture unit for capturing a change area included in the changed frame compared to the previous frame;
A still image compression technique is selected in consideration of any one or more of the size of the change area and image properties corresponding to the change area, and the change area corresponding to one frame by using the still image compression technique. An encoding unit for encoding a still image; And
Sending unit for performing a still image-based cloud streaming service by transmitting the still image-encoded change area to the user
Including,
The encoding unit, when the size of the change area is greater than or equal to a preset reference value, selects the still image compression technique in consideration of the image property. delete delete delete delete delete delete The method according to claim 1,
The capture unit
And capturing a changed area as the change area compared to a screen area corresponding to the previous frame among the screen areas corresponding to the changed frame. The method of claim 8,
The capture unit
A cloud streaming server, comprising: detecting a section in which a frame change is small among the entire frame period to be transmitted to the user's terminal device, and capturing the change area in a section in which the frame change is small. The method of claim 9,
The capture unit
A cloud streaming server, characterized in that detecting an event type of an application generated from the user's terminal device to detect a section in which the frame change is small. Capturing a change area included in the changed frame compared to the previous frame;
A still image compression technique is selected in consideration of any one or more of the size of the change area and image properties corresponding to the change area, and the change area corresponding to one frame by using the still image compression technique. Encoding the still image; And
Transmitting the still image-encoded change region to a user to perform a still image-based cloud streaming service
Including,
The step of encoding is:
When the size of the change area is greater than or equal to a preset reference value, the still image compression method is selected in consideration of the image property. delete delete delete delete delete delete delete delete Capturing a change area included in the changed frame compared to the previous frame, and selecting a still image compression technique in consideration of any one or more of the size of the change area and image properties corresponding to the change area, and the A cloud streaming server that performs a still image-based cloud streaming service by encoding the change region corresponding to one frame using a still image compression technique and transmitting the still image encoded change region to a user; And
Terminal receiving an application execution result screen corresponding to the cloud streaming service from the cloud streaming server
Including,
Cloud streaming server,
When the size of the change region is greater than or equal to a preset reference value, the still image compression technique is selected in consideration of the image property.

Images