KR20150144458A - Method and device for delivery of scalable digital content - Google Patents

Abstract

The present invention relates to a method for requesting a digital content including the steps of: setting a first communications connection with a server; setting a second communications connection with the server; transmitting a first request regarding a plurality of basic layer data segments through the first communications connection; and transmitting at least one second request regarding at least one enhanced layer data segment through the second communications connection, wherein at least one layer data segment and at least a portion of the basic layer data segments form at least a portion of the encoded stream of the digital content.

Description

[0001] METHOD AND DEVICE FOR DELIVERY OF SCALABLE DIGITAL CONTENT [0002]

This disclosure relates generally to the streaming of scalable digital content.

Recent advances in communication technology have resulted in an increase in multimedia communications beyond simple text and voice communications. In particular, with the surge in the Internet, a variety of online multimedia content providers such as Netflix, Hulu, and YouTube have emerged in recent years. In addition, due to the development of digital multimedia and other related technologies, the range of end-user devices capable of receiving content from such on-line multimedia content providers may range, for example, from a personal computer Smart phones, digital televisions, and video game consoles. In recent years, multimedia traffic occupies at least a substantial portion of the bandwidth of the Internet, if not all of it.

In keeping with the above developments, there has been a continuing effort to optimize the delivery of digital content over the Internet so that end-users using the services provided by online multimedia content providers may have the best experience. The multimedia content can be provided to the end-users with variable quality. For example, YouTube currently offers video content at various display resolutions such as 360p, 480p, and 720p. However, the quality of the content delivered may depend on various factors such as the performance of the end-user device requesting the content (e.g., the processing power of the end-user device and the size of the display) and the available network bandwidth at the time of digital content delivery , And may require some adjustment even during delivery of the content.

Embodiments of the disclosed subject matter relate to providing methods and devices for dynamically adjusting the quality of digital content delivered over a communications network in a fast and efficient manner without wasting bandwidth of the communications network. The following summary is a brief summary of the disclosure in order to provide a basic understanding of some aspects of the various embodiments of the disclosure. This summary is not an exhaustive summary of the disclosure. It is not intended to identify key or critical elements of the disclosed subject matter nor to delineate the scope of the disclosed subject matter. Its sole purpose is to present some concepts in a simplified form as a preface to a more detailed explanation to be discussed later.

Some embodiments provide a method for requesting digital content, for example. In such embodiments, the method comprises: establishing a first communication connection with the server; Establishing a second communication connection with the server; Sending a first request for a plurality of base layer data segments over the first communication connection to the server; And transmitting at least one second request for one or more enhancement layer data segments over the second communication connection to the server, wherein the at least a portion of the one or more enhancement layer data segments and the plurality of base layer data segments comprises the digital And configure at least a portion of the encoded stream of content.

In the above embodiments, the method may further comprise receiving and decoding the one or more enhancement layer data segments along with the at least a portion of the plurality of base layer data segments to provide a decoded stream of the encoded stream . The first and second communication connections may each be a transport layer connection that provides ordered, error-checked, and / or reliable delivery of the base layer and / or enhancement layer data segments. The transmitting the first request may include sending a request to the server to transmit the plurality of data segments via the first communication connection in a progressive streaming mode. The method includes storing the base layer and enhancement layer data segments in a buffer; Determining a fullness level of the buffer; And communicating with the server to limit the transfer rate of the plurality of base layer data segments based on the level of integrity of the buffer. Wherein communicating with the server comprises modulating a temporal spacing between a plurality of acknowledgments (ACKs) to be sent to the server, each of the plurality of acknowledgments responding to successful receipt of at least some of the plurality of base layer data segments Transmitted < / RTI > Communicating with the server may include communicating with the server to limit the transfer rate to inversely proportionate to the level of integrity of the buffer. Wherein transmitting the one or more second requests may include transmitting the one or more second requests over the second communication connection based on an adaptive streaming scheme. The method includes storing the base layer and enhancement layer data segments in a buffer; Estimating an available network bandwidth; And determining one or more enhancement layer data segments to be subsequently received based on the estimated available network bandwidth and the integrity level of the buffer. Estimating the available network bandwidth may include estimating available network bandwidth using the first communication connection. The step of determining the one or more enhancement layer data segments to be subsequently received may comprise determining a network bandwidth to be allocated to the second communication connection based on the estimated available network bandwidth.

Other embodiments may provide a method for providing digital content, for example. The method includes receiving a first request for a plurality of base layer data segments from a client over a first communication connection; Sequentially transmitting the plurality of base layer data segments via the first communication connection to the client in response to the first request; Receiving at least one second request for one or more enhancement layer data segments from the client over a second communication connection, the at least one enhancement layer data segment and at least a portion of the plurality of base layer data segments being associated with the digital content ≪ / RTI > And transmitting the one or more enhanced layer data segments over the second communication connection to the client in response to the at least one second request.

In the above embodiments, the first communication connection and the second communication connection are each a transport layer connection number that provides ordered, error-checked and / or reliable delivery of the base layer and / or enhancement layer data segments, have. The transmitting of the plurality of base layer data segments may comprise transmitting the plurality of base layer data segments in a progressive streaming mode. The transmitting of the one or more enhancement layer data segments may comprise transmitting the one or more enhancement layer data segments in an adaptive streaming mode.

Still other embodiments may provide a method for receiving digital content, for example. The method comprising: determining a level of integrity of a buffer for storing a plurality of base layer data segments received from a server and one or more enhancement layer data segments; And allocating available network bandwidth to at least one of the plurality of base layer data segments and the one or more enhancement layer data segments based on the level of vulnerability of the buffer.

In the above embodiments, allocating the available network bandwidth may further comprise communicating with the server to limit the transfer rate of the plurality of base layer data segments based on the level of vulnerability of the buffer . The step of allocating the available network bandwidth may further comprise determining one or more enhancement layer data segments to be subsequently received based on the level of integrity of the buffer. Wherein communicating with the server comprises modulating the temporal spacing between a plurality of acknowledgments (ACKs) to be sent to the base layer access unit, each of the plurality of acknowledgments including at least some of the plurality of base layer data segments Lt; / RTI > is received in response to successful receipt of the request. Communicating with the server may include communicating with the server to limit the transfer rate in inverse proportion to the level of the integrity of the buffer. The method may further comprise establishing a first communication connection for receiving the plurality of base layer data segments and a second communication connection for receiving the one or more enhancement layer data segments. The method may further include estimating an available network bandwidth using the first communication connection.

Still other embodiments may provide, for example, a device for requesting digital content. Wherein the device is configured to establish a first communication connection with a server and receive a first request for a plurality of sequential base layer data segments over the first communication connection; And an enhancement layer access unit configured to establish a second communications connection with the server and to transmit at least one second request for one or more enhancement layer data segments over the second communications connection, And at least a portion of the plurality of base layer data segments constitute at least a portion of an encoded stream of the digital content.

In the above embodiments, the device is configured to decode the one or more enhancement layer data segments with the at least a portion of the plurality of base layer data segments to provide the at least a portion of the decoded stream of the encoded stream Decoder. The first and second communication connections may each be a transport layer connection providing ordered, error-checked, and / or reliable delivery of the base layer and / or enhancement layer data segments. The first request may include a request to transmit the plurality of base layer data segments over the first communication connection in a progressive streaming mode. Wherein the device further comprises a buffer for storing the base layer and enhancement layer data segments, the communication unit comprising: a buffer poolless allocation unit configured to determine a level of integrity of the buffer; And a throttling unit configured to communicate with the server to limit the transmission rate of the plurality of base layer data segments. Wherein the throttling unit is configured to modulate the temporal spacing between a plurality of acknowledgments (ACKs) to be sent to the server, each of the plurality of acknowledgments being transmitted in response to successful receipt of at least a portion of the plurality of base layer data segments . The throttling unit may be configured to communicate with the server to limit the transmission rate in inverse proportion to the level of the buffer ' s buffer. The enhancement layer access unit may be configured to transmit the one or more second requests over the second communication connection based on an adaptive streaming scheme. Wherein the device further comprises a buffer for storing the base layer and enhancement layer data segments, wherein the communication unit further comprises a bandwidth estimation unit configured to estimate an available network, the enhancement layer access unit comprising: And a scheduling unit configured to determine one or more enhancement layer data segments to be subsequently received based on a possible network bandwidth and a health level of the buffer. The bandwidth estimation unit may be configured to estimate the available network bandwidth using the first communication connection.

Still other embodiments may provide, for example, a device for providing digital content. In such embodiments, the device comprises: a storage unit for storing together a plurality of base layer data segments and a plurality of enhancement layer data segments constituting an encoded version of the digital content; And receive a first request for the plurality of base layer data segments from a client over a first communication connection; Sequentially send the plurality of base layer data segments via the first communication connection to the client in response to the first request; Receive at least one second request for one or more segments of the plurality of enhancement layer data segments from the client over a second communication connection; And a communication unit configured to transmit the one or more enhanced layer data segments over the second communication connection to the client in response to the at least one second request.

In the above embodiments, the first communication connection and the second communication connection are each a transport layer connection that provides ordered, error-checked and / or reliable delivery of the base layer and / or enhancement layer data segments, . The communication unit may be configured to transmit the plurality of base layer data segments in a progressive streaming mode. The communication unit may be configured to transmit the one or more enhancement layer data segments in an adaptive streaming mode.

Still other embodiments may provide, for example, a device for receiving digital content. The device comprising: a communication unit configured to receive a plurality of base layer data segments and one or more enhancement layer data segments; And a buffer configured to store the base layer and enhancement layer data segments, wherein the communication unit is configured to store the plurality of base layer data segments and at least one of the one or more enhancement layer data segments based on a level of health of the buffer Lt; RTI ID = 0.0 > network bandwidth. ≪ / RTI >

In the above embodiments, the communication unit may further include: a buffer fullness determination unit configured to determine the level of the flexibility of the buffer; And a base layer access unit configured to communicate with the server to limit the transmission rate of the plurality of base layer data segments based on the level of the security of the buffer. Wherein the communication unit comprises: a buffer fullness determination unit configured to determine the level of the integrity of the buffer; And an enhancement layer access unit configured to determine one or more enhancement layer data segments to be subsequently received based on the level of the security of the buffer. Wherein the base layer access unit is configured to modulate temporal spacing between a plurality of acknowledgments (ACKs) to be transmitted to the server, each of the plurality of acknowledgments responding to successful receipt of at least some of the plurality of base layer data segments May be transmitted. The base layer access unit may be configured to communicate with the server to limit the transmission rate in inverse proportion to the level of the buffer's integrity. The communication unit may be configured to establish a first communication connection for receiving the plurality of base layer data segments and a second communication connection for receiving the one or more enhanced layer data segments. The communication unit may further comprise a bandwidth determination unit configured to estimate an available network bandwidth using the first communication connection.

1 is a schematic diagram of a system for providing digital content in accordance with some embodiments.
2 is a detailed block diagram illustrating a server, such as the server shown in FIG.
3 is a non-limiting illustrative drawing of a layered stream structure of a scalable video coding extension of the H.264 / AVC (Advanced Video Coding) standard, in accordance with some embodiments.
4 is a detailed block diagram illustrating a client device, such as the client shown in FIG.
5 is a diagram illustrating selecting one or more enhancement layer sub-streams based on the amount of available network bandwidth, in accordance with some embodiments.
Figure 6 is a flow diagram of a method performed by a client device, such as the client of Figure 1, for receiving digital content, in accordance with some embodiments.
7A is a conceptual signaling diagram illustrating message exchange in a progressive streaming mode, in accordance with some embodiments.
7B is a conceptual signaling diagram illustrating message exchange in an adaptive streaming mode, in accordance with some embodiments.
Figure 8 is a flow diagram of a method performed by a server device, such as the server of Figure 1, to provide digital content, in accordance with some embodiments.
9 is a detailed block diagram illustrating another embodiment of a client device, such as the client shown in FIG.
10 is a detailed block diagram illustrating an embodiment of a base layer (BL) access unit shown in FIG.
11 is a diagram of determining throttling parameters from buffer fullness, in accordance with some embodiments.
12 is a detailed block diagram illustrating an embodiment of the enhancement layer (EL) access unit shown in FIG.
13A and 13B are diagrams illustrating selecting one or more enhancement layer data segments, in accordance with some embodiments.
FIG. 14 is a flow chart performed by a client device, such as the client of FIG. 1, to divide network bandwidth for base layer and enhancement layer data segments according to some embodiments.
15 is a block diagram illustrating a computing system architecture that may be used to implement one or more of the components and processes thereof described herein.

Various embodiments are now described with reference to the drawings, wherein like reference numerals are used to refer to like elements throughout. In the following description, for purposes of explanation, numerous specific details are set forth in order to provide a thorough understanding of one or more of the constituent elements. It may be evident, however, that such embodiment (s) may be implemented without these specific details. In other instances, well-known structures and devices are shown in block diagram form in order to facilitate describing one or more embodiments.

According to some embodiments of the present disclosure, Figure 1 is a schematic diagram of a system 100 for providing digital content. Referring to Figure 1, a system 100 includes a server 110 configured to provide digital content, a communications network 120, and a communications link 120 to the communications network 120 for requesting and receiving digital content from the server 110. [ A plurality of clients 131-133 (collectively referred to below as clients 130) that are coupled to the client 130-133. Although only three clients 131-133 are illustrated in FIG. 1 for ease of illustration, fewer or more client devices may be connected to the communications network 120 to access the server 110 Should be recognized.

The server 110 may include one or more computing devices for communicating with the clients 130 and optionally other communication entities (not shown) via the communication network 120 or software and / or hardware modules (E. G., A web server). ≪ / RTI > Examples of such computing devices include, but are not limited to, a dedicated computer or a plurality of networked computers capable of operating under a client-server architecture.

In one embodiment, the server 110 may be configured to store the encoded digital content to be delivered at various quality or "scalable" levels (e.g., at a display resolution of 360p, 480p, 760p, or 1080p) . In one embodiment, the server 110 receives a request for digital content from clients 131, 132, and / or 133 and, in response thereto, generates a plurality of different types of sub-streams (e.g., Can be used (e.g., combined, decoded, etc.) with the base layer sub-stream to provide a base layer sub-stream that can be independently decoded to provide quality video and improved or improved quality digital content One or more enhancement layer sub-streams). Examples of digital content include any type of audio (e.g., music, noise, etc.), video (video selectively coupled to audio), images (e.g., still images) Text messages, hypertext messages, email, Short Message Service (SMS) messages, etc.), and other multimedia content.

Communication network 120 may be configured to allow communication requests to establish communication connections between any entities connected therewith (e.g., between server 110 and clients 131, 132 and / or 133) A plain old telephone service (POTS) network, a mobile network, a data communication network, and the like, which may be routed and / or routed. In one embodiment, communication network 120 may also be comprised of one or more public and / or private communication networks. Examples of such communication networks are Public Switched Telephone Network (PLNN), Public Land Mobile Network (PLMN), Universal Mobile Telecommunications System (UMTS), Long-Term Evolution (LTE) : Long Term Evolution) network, the Internet, and the like.

Clients 130 may be end-user devices or software and / or hardware module (s) installed therein (e.g., a web browser) for communicating with server 110 via communications network 120, respectively. Examples of such end-user devices include any type of device capable of playing digital content received from a personal computer, a personal digital assistant (PDA), a smart phone, a digital television, a video game console, But are not limited to.

In one embodiment, clients 130 may each be configured to request and receive digital content from server 110, for example, in the form of a base layer sub-stream and / or one or more enhancement layer sub- have. In another embodiment, clients 130 may each be configured to establish separate communication connections with server 110 to request and receive different layers of sub-streams. For example, each of the clients 130 may establish a first communication connection to the base layer sub-stream, and one or more separate second communication connections to some or all of the enhancement layer sub-streams.

2 is a detailed block diagram illustrating the server 110 shown in FIG. 2, the server 110 may include, without limitation, a storage unit 210, a control unit 220, and a communication unit 230.

The storage unit 210 may be configured with any suitable temporary and / or permanent memory. Examples of such memories include, but are not limited to, high speed random access memory (e.g., DRAM, SRAM, DDR RAM or other random access solid state memory devices), non-volatile memory , Flash memory devices, or other non-volatile solid state storage devices). In some embodiments, storage unit 210 may include one or more storage devices remotely located from control unit 220 and / or remotely located at multiple locations.

In one embodiment, the storage unit 210 stores the encoded digital content in accordance with a scaling coding algorithm (e.g., storing a plurality of base layer data segments and a plurality of enhancement layer segments constituting an encoded stream of digital content ). Here, the term "scalable coding" refers to a variant (e.g., a video having a display resolution of 360p, 480p, 720p, or 1080p) differently scaled from a source stream of digital content (e.g., video with a display resolution of 720p) Quot; refers to one or more types of coding that produce a plurality of sub-streams of different layers, which can be used to provide digital content with a plurality of sub-streams. FIG. 3 illustrates a non-limiting example of a layered stream structure of H.264 / SVC stream 300. Referring to FIG. 3, an H.264 / SVC stream 300 encoded from a source video stream includes: (a) a set of base layer data segments (or data "chunks") (B ₀ , B ₁ , B ₂ ,. ... and B _{N -1} ); And (b) a set of the first enhancement layer data segment _{(E 0, E 1, E} 2, ... _{N -1,} and E) and a series of second enhancement layer data segment _{(E '0, E' 1} , E _'2, ..., and E' _{N -1),} respectively consisting of first and second enhancement layer sub-streams (321 and 322) (hereinafter referred to as enhancement layer sub-streams 320 may be referred to collectively as Lt; / RTI >

In one embodiment, base layer sub-stream 310 provides video at a base quality level (e.g., a display resolution of 360p) that is lower than the quality level of the source video stream (e.g., a display resolution of 760p) And can be decoded independently. In a non-limiting example, the base layer data segments (B ₀ , B ₁ , B ₂ , ..., and B _N-1 ) each include encoded video data corresponding to successive time intervals of the same length It may be (e.g., for a video of the second M-length, N of a base layer data segment _{(B 0, B 1, B} 2, ... , and B _N-1) are consecutive M / N the length of each video Lt; RTI ID = 0.0 > time periods < / RTI >

In one embodiment, the first enhancement layer sub-stream 321 includes a base layer sub-stream 310 for reconstructing digital content to improve the quality level of the video (e.g., to improve the display resolution to 480p) ≪ / RTI > Non-limiting example, the first enhancement layer data segment (E ₀₎ may be used together with the base layer data segment (B ₀₎ in order to improve the display resolution of the video corresponding to the first M / N seconds to 480p, The first enhancement layer data segment E ₁ may be used with the base layer data segment B ₁ to improve the display resolution of the video corresponding to the next M / N second to 480p, and so on. In one embodiment, the second enhancement layer sub-stream 322 includes a base layer sub-stream 310 to further improve the quality level of the video (e.g., to further improve the display resolution to 760p) And the first enhancement layer sub-stream 321. In a non-limiting example, the second enhancement layer data segment (E ' ₀ ) includes a base layer data segment B ₀ and a first enhancement layer data segment B ₀ to further improve the display resolution of the video corresponding to the first M / And the second enhancement layer data segment (E ' ₁ ) may be used with the enhancement layer data segment (E ₀ ) to further improve the display resolution of the video corresponding to the next M / N seconds to 760 p, (B ₁ ) and the first enhancement layer data segment (E ₁ ). The technical details necessary to encode and decode the base and enhancement layer sub-streams are well known and may be implemented without further explanation in this disclosure.

Referring again to Figure 2, the storage unit 210 may include: (a) one or more base layer files (e.g., base layer (BL) files 211); And (b) one or more enhancement layer files (e.g., first and second enhancement layer (EL) files 212 and 213). One or more base layer files may comprise a series of base layer data segments (B ₀ , B ₁ , B ₂ , ..., and B _N-1 ) of base layer sub- In addition, one or more enhancement layer files may include a series of first enhancement layer data segments (E ₀ , E ₁ , E ₂ , ..., and E _{N -1} ) of the first enhancement layer sub- May include a series of second enhancement layer data segments (E ' ₀ , E' ₁ , E ' ₂ , ..., and E' _{N -1} ) of layer sub-

In a non-limiting example, the storage unit 210 includes all of the base layer data segments (B ₀ , B ₁ , B ₂ , ..., and B _{N -1} ) of the base layer sub- You can store one base layer file. In another non-limiting example, storage unit 210 may store a plurality of base layer files, each of a plurality of base layer files comprising a set of base layer data segments (B ₀ , B ₁ , B ₂ , ..., and B _{N -1} ). In a non-limiting example, the storage unit 210 may include two enhancement layer files, one of which is the first enhancement layer data segment E ₀ , E ₁ , E ₂ , ..., and E _{N -1} ) of the second enhancement layer sub-stream 322 and the other includes the second enhancement layer data segments E ' ₀ , E' ₁ , E ' ₂ , ..., and E ' _N-1 ). In another non-limiting example, the storage unit 210 may store a plurality of enhancement layer files, each of which includes a first enhancement layer data segment E ₀ , E ₁ , E ₂ , ... , And E _{N -1} ) and second enhancement layer data segments (E ' ₀ , E' ₁ , E ' ₂ , ..., and E' _{N -1} ).

The storage unit 210 may store information for locating at least a portion of the base layer and / or enhancement layer file (s) (e.g., a Uniform Resource Identifier (URI) Uniform resource identifier) or the URI of the enhancement layer file. Examples of such information include, but are not limited to, dynamic adaptive streaming over HTTP (DASH) or media description description (MPD) as defined in MPEG-DASH.

The storage unit 210 controls communication unit 230 to control the overall operation of the server 110 and to perform and / or implement any of the processes, operations and methods described herein with respect to the server 110. [ Or any number of software programs including a set of instructions to be executed by the control unit 220 to control the control unit 220. [ For example, the storage unit 210 may include: (a) one or more operating system programs for handling various base system services and performing hardware dependent tasks, and / or (b) communication with other communication entities Lt; RTI ID = 0.0 > and / or < / RTI >

The control unit 220 may include any number of hardware and / or software module (s) (e.g., specialized analog and / or digital control circuitry and / or one or more operating Which may be implemented by one or more general purpose processors executing a set program). For example, control unit 220 may control the transfer of data to storage unit 210 and communication unit 230 and from storage unit 210 and communication unit 230 (e.g., communication Retrieves and forwards one or more of the base layer and enhancement layer data segments from storage unit 210 to communication unit 230 upon receiving a data transfer request from unit 230).

The communication unit 230 may be implemented by any number of hardware and / or software module (s) (e.g., one or more general purpose processors executing specialized analog and / or digital control circuits and / ). ≪ / RTI > The communication unit 230 may communicate with one or more communication entities (e.g., server 110 and clients 130 in FIG. 1) via a communication network (e.g., communication network 120 in FIG. 1) Establish communication connections, and assist in exchanging information with communication entities over established communication connections. For this purpose, the communication unit 230 may be configured to support various public and / or private network protocols for establishing communication connections and for communicating data over a communication network such as the Internet. Such network protocols may be implemented in a network layer protocol (s) (e.g., Internet Protocol (IP)), transport layer protocol (s) (e.g., Transmission Control Protocol , User Datagram Protocol (UDP), etc.) and application layer protocol (s) [e.g., Hypertext Transfer Protocol (HTTP), etc.). The communication unit 230 may also be configured to support one or more techniques for delivering a stream of data over a communication network. Examples of such streaming techniques include, but are not limited to, Dynamic Adaptive Streaming over HTTP (DASH) or HAS (HTTP Adaptive Streaming) such as MPEG-DASH.

In one embodiment, communication unit 230 is configured to: send one or more requests to establish one or more communication connections between server 110 and client 131 from a client (e.g., client 131 of FIG. 1) And in response, generate and send one or more responses to the client 131 to establish communication connections with the client. In one embodiment, each of the communication connections includes a transport layer connection (i. E., Connection-oriented, error checking and / or error checking) that provides ordered, error- A communication connection of a transport layer protocol that provides reliable transport functions). Examples of such transport layer connections include, but are not limited to, TCP connections that may be established according to the TCP three-way handshake procedure.

In the above embodiment, the communication unit 230 further comprises (a) one or more requests (e.g., HTTP GET requests) to provide one or more of the base layer and / or enhancement layer data segments, (E.g., client 131, 132, or 133 in FIG. 1) through one of the client devices (e.g. (b) receiving one or more base layer and / or enhancement layer data segments requested from the storage unit 210 under the control of the control unit 220; And (c) send one or more base layers and / or enhancement layer data segments to a client (e.g., client 131, 132, or 133 in FIG. 1) via one of the established communications connections .

An HTTP GET request (discussed above) allows a client (e.g., client 131, 132, or 133 in FIG. 1) to request data from a server over a TCP connection, as defined under HTTP standards Request to receive. The HTTP GET request may include URI (uniform resource information) of the data file and, optionally, a "byte-range" parameter indicating a portion of the data file to be downloaded. In a non-limiting example, communication unit 230 is configured to: (a) send an HTTP GET request (i.e., a "non-byte- Range "HTTP GET request) from a client (e.g., client 131, 132, or 133 in FIG. 1) over a first communication connection; (b) sending an HTTP 200 OK response indicating successful receipt and authentication of the HTTP GET request received from the client over the first communication connection; And (c) receive the base layer data segments (B ₀ , B ₁ , B ₂ , ..., and B _N-1 ) in the base layer file 211, (E.g., client 131, 132, or 133 in FIG. 1).

In another non-limiting example, the communication unit 230 is configured to: (a) provide a "byte-range" parameter that indicates the contiguous portion of the base layer file 211 along with the URI of the base layer file 211 (E.g., a "byte-range" HTTP GET request) from a client (eg, client 131, 132, or 133 of FIG. 1) via a first communication connection; (b) sending an HTTP 200 OK response to the client 131, 132, or 133 via the first communication connection; And (c) transmitting to the client 131, 132, or 133 via the first communication connection a successive number of base layer data segments (B ₀ , B ₁ , B ₂ ) included in successive portions of the base layer file 211 , ..., and B _{N -1} ).

In another non-limiting example, communication unit 230 may include: (a) an enhancement layer file 212, which includes a URI of one of the enhancement layer files 212 and 213 and a first or second enhancement layer data segment Or " 213 "parameter) indicating a portion of a client (e.g., client 131, 132, or 213 in FIG. 1) via a second communication connection that is different than the first communication connection 133), < / RTI > (b) sending an HTTP 200 OK response to the client 131, 132, or 133 via the second communication connection; And (c) send the requested first or second enhancement layer data segment to the client 131, 132, or 133 via the second communication connection.

4 is a detailed block diagram illustrating the client 131 shown in FIG. 4, the client 131 may include, without limitation, a storage unit 410, a control unit 420, a communication unit 430, and a decoder 440.

The storage unit 410 may be configured with any suitable temporary and / or permanent memory configured to store one or more operating system programs, other system programs, and / or one or more communication programs. In one embodiment, the storage unit 410 may store information (e.g., a URI of the base layer file and / or information for determining the location of the base layer and / or enhancement layer file (s) URI of the enhancement layer file]. Examples of such information include, but are not limited to, an MPD (e.g., MPD 411) as defined in MPEG-DASH. In one embodiment, the storage unit 410 may store data of the digital content (e.g., basic and / or enhancement layer sub-streams received from the communication unit 430 that constitute at least a portion of the encoded stream of digital content (E. G., Data segments of data). ≪ / RTI > The storage unit 410 may also include other permanent and / or temporary data needed for the operation of the control unit 420.

The storage unit 410 may further store a media player program (not shown). The media player program can be configured to respond to user input for playing digital content (e.g., playing a song, displaying a video, etc.). The media player program can be invoked by invoking the control unit 420 to issue one or more instructions for generating and sending one or more HTTP GET requests for enhancement layer data segments to match the display resolution selected by the user Lt; / RTI > may be further configured to respond to user input to improve the display resolution of the digital content being played.

The control unit 420 may include any number of hardware and / or software module (s) (e.g., specialized analog and / or digital control circuitry and / or one or more operating Implemented by one or more general purpose processors executing a set program). For example, the control unit 420 may be configured to receive data (e.g., from the base unit and enhancement layer sub-streams received from the communication unit 430) between the storage unit 410, the communication unit 430 and the decoder 440 Of data segments).

The communication unit 430 may be implemented by any number of hardware and / or software module (s) (e.g., one or more general purpose processors executing specialized analog and / or digital control circuits and / ). ≪ / RTI > The communication unit 430 may communicate with one or more communication entities (e.g., server 110 and clients 130 in FIG. 1) via a communication network (e.g., communication network 120 in FIG. 1) Establish a communication connection, and assist in exchanging information with communication entities through established communication connections. For this purpose, the communication unit 430 may be configured to support various public and / or private network protocols (e.g., TCP, HTTP, etc.). In addition, the communication unit 450 may be configured to support one or more streaming techniques, such as DASH.

In one embodiment, the communication unit 430 receives a selection input indicating at least one of the digital content available at the server 110 from, for example, the end-user of the client 131, May be configured to establish a separate communication connection with server 110 to request and receive data segments of different layers. In one embodiment, communication unit 430 is configured to: (a) establish a first communication connection (e.g., a first TCP connection) with server 110 and transmit a first request for a base layer sub- A base layer access unit (431) configured to: And (b) establishing one or more second communication connections (e.g., one or more second TCP connections) with the server 110 to establish at least one second request for one or more enhanced layer sub- And an enhancement layer access unit 432 configured to transmit.

In a non-limiting example, the enhancement layer access unit 432 may be configured to establish a second communications connection with the server 110 to receive multiple enhancement layer sub-streams (e.g., 2 enhancement layer sub-streams 321 and 322). In another non-limiting example, the enhancement layer access unit 432 may be configured to establish a single second communication connection for each enhancement layer sub-stream (e.g., 1 enhancement layer sub-stream 321 and the other for the second enhancement layer sub-stream 322).

In one embodiment, the base layer access unit 431 may be configured to send a request to the server 110 to stream the base layer sub-stream over the first communication connection established in the progressive streaming mode. Herein, the "progressive streaming mode" means that the entirety of the sub-stream from the server to the client by a single request from the client (e.g., client 131, 132, or 133) Or at least a predefined number of contiguous data segments are streamed continuously to the client 131, 132, or 133.

In a non-limiting example, the base layer access unit 431 may communicate with the server 110 over a first TCP connection to continuously receive all of the base layer data segments in the base layer file from the server 110 Quot; non-byte-range "HTTP GET request that includes the URI of the base layer file but does not include the" byte-range "parameter). In the above example, the base layer access unit 431 may retrieve the URI of the base layer file from the MPD 411 in the storage unit 410 to generate an HTTP GET request. In another non-limiting example, the base layer access unit 431 is configured to receive base layer data segments in successive portions of the base layer file from the server 110 over a first TCP connection, Quot; HTTP GET request (including the URI of the base layer file and also including a "byte-range" parameter)

In one embodiment, the enhancement layer access unit 432 is configured to send one or more requests to the server 110 for streaming one or more enhancement layer sub-streams over one or more established second communications connections in an adaptive streaming mode . Herein, the term "adaptive streaming mode" means that only selected ones of the data segments of the sub-stream of digital content are transmitted as a series of requests (each request including at least one of the entire data segments to the client 132, or 133) to request from the server to dynamically adjust the quality level of the digital content) to the client 131, 132, or 133.

In a non-limiting example, the enhancement layer access unit 432 may: (a) adaptively select one or more enhancement layer data segments to be downloaded from the server 110; And (b) send a separate HTTP GET request for each of the selected enhancement layer segments. In the example above, the enhancement layer access unit 432 may select one or more enhancement layer data segments according to any of the various adaptation algorithms provided for adaptive streaming.

In one example, enhancement layer access unit 432 may select one or more enhancement layer data segments based on the amount of network bandwidth available for digital content. In the example above, the enhancement layer access unit 432 may include a bandwidth determination unit (not shown) configured to determine the available network bandwidth according to one or more of various manners. For example, the bandwidth determination unit may be configured to: determine the amount of time it takes to send one or more data segments of a defined length to the server 110 and to receive one or more responses from the server 110 to confirm successful receipt of one or more data segments , The available network bandwidth can be estimated. Further, in the example above, the enhancement layer access unit 432 may select one or more enhancement layer data segments to receive based on the estimated available network bandwidth and prescribed thresholds.

5 is a diagram illustrating selecting one or more enhancement layer sub-streams based on the amount of available network bandwidth. Referring to FIG. 5, the enhancement layer access unit 432 is configured to: (a) receive no enhancement layer data segments when the available network bandwidth is below a first threshold TH ₀ ; (b) receive one enhancement layer segment belonging to a first enhancement layer sub-stream when the available network bandwidth is between a first threshold (TH ₀ ) and a second threshold (TH ₁ ); And (c) when the available network bandwidth is greater than or equal to a second threshold value TH ₁ , one of the enhancement layer segments belongs to the first enhancement layer sub-stream and the other belongs to the second enhancement layer sub- Can be selected. For example, as shown in FIG. 5, a base layer access unit 431 receives base layer segments (B ₀ , B ₁ , and B ₂ ) from a server 110 over a first communication connection , an enhancement layer access unit 432 may be selected to receive the first enhancement layer segments from the server (110) (E ₁ and E ₂₎ and the second enhancement layer segments (E _'1) on a second communication connection . It should be understood that the adaptation algorithm described above is only one example, and that any other adaptation algorithm, such as the algorithm used in Microsoft's Silverlight, and other known algorithms may be used.

In one embodiment, the communication unit 430 is capable of receiving, under control of the control unit 420, some or all of the base layer and / or enhancement layer segments received by the base layer and enhancement layer access units 431 and 432 To buffer 412 in storage unit 410 for storage. For example, in the example described with respect to FIG. 5, the communication unit 430 may include base layer segments B ₀ , B ₁ , and B ₂ , first enhancement layer segments E ₁ and E ₂ , The second enhancement layer segment (E ' ₁ ) may be forwarded to the buffer 412 for storage.

Decoder 440 may be configured to receive base layer and / or enhancement layer segments from buffer 412 of storage unit 410 for decoding under control of control unit 420. [ In one embodiment, the decoder 440 fetches and decodes the base layer data segments and / or the corresponding enhancement layer data segments from the buffer 412 to derive the digital content therefrom, for example, Quality level. ≪ / RTI > Buffer 412 described above is that stores the base layer segments (B _0, B _1, and B _2), the the first enhancement layer segments (E ₁ and E ₂₎ and the second enhancement layer segments (E _'1) In the illustrated example, the decoder 440: (a) invokes and decodes the base layer segment B ₀ to generate the first M / N seconds of video at 360p resolution; (b) recall and decode the base layer segment (B ₁ ) and the first and second enhancement layer segments (E ₁ and E ' ₁ ) to produce the next M / N seconds of video at 760p resolution; And (c) recall and decode the base layer segment B ₂ and the first enhancement layer segments E ₂ to generate the next M / N seconds of video at 480p resolution. The technical details necessary to decode the base layer and / or enhancement layer data segments are well known and may be implemented without further explanation.

In the above embodiments, by setting up separate communication connections (e. G., TCP connections) to receive data segments of different types of tiers, the client 131 can establish a minimum over Stream (with a single HTTP GET request can initiate progressive streaming of the base layer sub-stream over the first communication connection only with the head and better bandwidth utilization), and the base layer data segment To one or more enhancement layer data segments received over one or more separate second communication connections at the same time, The quality of the digital contents can be adaptively adjusted.

6 is a flow diagram of a method performed by a client device, e.g., client 131, to receive digital content. 6, in step 610 performed by the base layer access unit 431 of the client 131, a first TCP connection with the server (e.g., the server 110 of FIG. 1) Stream is received from the server 110 in the progressive streaming mode via the first TCP connection, for example, at step 620 performed by the base layer access unit 431 of the client 131 A first request is sent to the server 110. 7A is a conceptual signaling diagram for message exchange in a progressive streaming mode. 7A, the base layer access unit 431 of the client 131 may perform a TCP-3 directional handshake procedure (e.g., by using a synchronization (SYN) and / or acknowledgment (E. G., By exchanging a series of TCP segments including acknowledgment (ACK) control bit flags). In the following, the base layer access unit 431 of the client 131 can send a "non-byte-range" HTTP GET request containing the URI of the base layer file to the server 110 via the established first TCP connection have. Upon successful receipt of the HTTP GET request, the server 110 first transmits an HTTP 200 OK response indicating successful reception and authentication of the HTTP GET request received from the client 131 via the first TCP connection (B ₀ , B ₁ , B ₂ , ..., and B _{N -1} ) in the base layer file requested to the client 131 over the first TCP connection.

In one embodiment, the base layer access unit 431 of the client 131 may send a TCP ACK after successfully receiving a predetermined number of base layer data segments from the server 110. In addition, in the above embodiment, after transmitting a predetermined number of base layer data segments, the server 100 only transmits subsequent base layer data (hereinafter referred to as base layer data) only when receiving a TCP ACK for previously transmitted base layer data segments Segment can be transmitted. The limiting example, as shown in Figure 7a, server 110 before the base layer data segment base layer data only subsequently, when receiving the TCP ACK for the (e. G., B ₀₎ segment (non- For example, B ₁ ).

In one embodiment, the base layer access unit 431 of the client 131 is configured to determine the base layer data segments B ₀ , B ₁ , B (B ₁ , B ₁ , B ₂ ) by adjusting the rate at which TCP ACKs are sent from the client 131 to the server 110 _2, ..., and a transmission rate (that is, the base layer data segment (B _0, B _1, B _2, ..., and B _N-1) by the client 131 from the server of the B _N-1) The transmission rate) can be indirectly adjusted. For example, a client (e.g., client 131, 132, or 133 in FIG. 1) may delay the transmission of TCP ACKs to reduce or increase the transmission rate of base layer data segments, )can do. This manner for a client (e.g., client 131, 132, or 133 in FIG. 1) to indirectly adjust the server's transfer rate may be referred to as "ACK paging ".

Upon successful reception of the last one of the base layer data segments (B ₀ , B ₁ , B ₂ , ..., and B _{N -1} ), the base layer access unit 431 of the client 131 sends a final TCP ACK And terminates the first TCP connection with the server 110. As can be seen from the above description, in the progressive streaming mode, only one HTTP GET request and the subsequent HTTP 200 OK response are transmitted from the server 110 to the client 131 as the base layer data segments B ₀ , B ₁ , B ₂ , ..., and B _{N -1} ).

6, at step 630, the enhanced layer access unit 432 of the client 131 sends one or more second TCP (s) to the server (e. G., The server 110 of FIG. 1) Connections are established and at step 640 performed by, for example, the enhancement layer access unit 432 of the client 131, one or more enhancement layer sub-streams are transmitted from the server 110 via one or more second TCP connections And transmits at least one second request to receive in an adaptive streaming mode.

7B is a conceptual signaling diagram illustrating message exchange in an adaptive streaming mode. Referring to FIG. 7B, the enhancement layer access unit 432 of the client 131 can establish a second TCP connection with the server 110 by performing a TCP three-way handshake procedure. Thereafter, the enhancement layer access unit 432 of the client 131 selects one of the video enhancement layer data segments (e.g., E ₁ ) and includes the URI of the enhancement layer file including the selected enhancement layer data segment An HTTP GET request can be sent to the server. If the enhancement layer file includes other enhancement layer data segments as well as other enhancement layer data segments, a byte-range parameter indicating a portion of the enhancement layer file containing the selected enhancement layer data segment may be included in the HTTP GET request. Upon successful receipt of the HTTP GET request, the server 110 first transmits an HTTP 200 OK response indicating successful reception and authentication of the HTTP GET request received at the client 131 via the second TCP connection, And sends the requested enhancement layer data segment (E ₁ ). Thereafter, when the server 110 receives the TCP ACK for the transmitted enhancement layer data segment E ₁ , the server 110 terminates the transmission and waits for another HTTP GET request to be received from the client 131. The enhancement layer access unit 432 of the client 131 continues to select and request the next enhancement layer data segments if necessary and terminates the second TCP connection with the server 110 upon completion of the video transmission.

Figure 8 is a flow diagram of a method performed by a server, e.g., server 110, to provide digital content. 8, in step 810 performed by, for example, the communication unit 230 of the server 110, a first request for a series of base layer data segments (e.g., all of the base layer data segments (E.g., an HTTP GET request for the client 131) from the client (e.g., client 131 of FIG. 1) over the first communication connection. For example, in step 820 performed by the communication unit 230 of the server 110, a series of base layer data segments are transmitted to the client device 131 via the first communication connection in response to the first request. For example, at step 830 performed by the communication unit 230 of the server 110, at least one second request for one or more enhancement layer data requests (e. G., One or more enhancement layer data segments) (E.g., HTTP GET request (s)) from the client 131 via the second communication connection. For example, in step 840 performed by the communication unit 230 of the server 110, the client 131 may request the one or more enhancement layer data segments requested in response to the at least one second request, Lt; / RTI >

The systems, devices, and methods described in this disclosure may be used to adaptively adjust network bandwidth allocated to base layer sub-streams and / or one or more enhancement layer sub-streams. For example, the total network bandwidth available for transmission of the requested digital content may be determined by various factors such as the fullness of the client side buffer (e.g., buffer 412 of client 131 of FIG. 4) Streams and one or more enhancement layer sub-streams based on one or more factors of the enhancement layer sub-streams.

FIG. 9 is a detailed block diagram illustrating another embodiment of the client 131 shown in FIG. 9, client 131 includes, without limitation, storage unit 910 (including MPD 911 and buffer 912); A control unit 920; A communication unit 930; And a decoder 940. The structure and function of the storage unit 910 (including the MPD 911 and the buffer 912), the control unit 920 and the decoder 940 are similar to those of the storage unit 410 (MPD 411) And a buffer 412), a control unit 420 and a decoder 440. Thus, for simplicity, the contents of storage unit 910 (including MPD 911 and buffer 912), control unit 920 and decoder 940 will not be described in further detail.

The communication unit 930 is similar to the communication unit 430 of Fig. 4 is a server (110) a set of the base layer segment (e.g., a digital content example, a set of the base layer of FIG segment (B _0, B _1, from B (BL) access unit 931 configured to set up a first communication connection (e.g., a first TCP connection) for requesting and receiving a plurality (e.g., ₂ , ..., and B _N-1 ) And one or more enhancement layer data segments (e.g., the first enhancement layer data segments E ₀ , E ₁ , E ₂ , ..., and E _{N -1} ) of the same digital content from the server 110 and a second enhancement layer data segment _{(E '0, E' 1} , E '2, ..., and E' _{N -1))} of at least one to request a part of it) to receive one of the second communication connection (e.g. (EL) access unit 932 that is configured to set up one or more second TCP connections (e.g., one or more second TCP connections). The base layer access unit 931 and the enhancement layer access unit 932 are the same as or similar to those described for the base layer access unit 431 and the enhancement layer access unit 432 of FIG. You can set up a connection.

In one embodiment, the communication unit 930 refers to the base layer data segments and the integrity level of the buffer 912 in the storage unit 910 to determine the network bandwidth available for transmission of digital content to base layer data segments < RTI ID = 0.0 > And one or more enhancement layer data segments. For this purpose, the communications unit 930 may be configured to: (a) send the entire network bandwidth or total transmission rate available for transmission of the requested digital content (e.g., the server 110 receives the base layer segments B ₀ , B _{1 , B 2, ..., B N} -1), the first enhancement layer data segment _{(E 0, E 1, E} 2, ..., E N -1) and the second enhancement layer data segment (E _'0 , E ' ₁ , E' ₂ , ..., and E ' _{N -1} ) of the transmission rate (s)); (BF) determination unit 934 configured to determine the level of fitness of the buffer 912 in the storage unit 910 (b).

Refers to the amount of digital content stored in the buffer relative to the total capacity of the buffer (e. G., Buffer 812). ≪ / RTI > In some embodiments, the total capacity of the buffer may be defined as the time (e.g., 30 seconds) required to reproduce the digital content in the buffer when the buffer is fully populated. Also, the bufferiness of the buffer may be expressed as the time required to reproduce the digital content currently stored in the buffer (e.g., 15 seconds when half of the buffer is full).

In one embodiment, bandwidth determination unit 933 may be configured to determine the overall available network bandwidth according to one or more of various manners. In one embodiment, the bandwidth determination unit 933 is configured to: send one or more data segments of a defined length to the server 110 and transmit one or more responses to the server 110 to confirm successful reception of one or more data segments By measuring the time taken to receive, the total available network bandwidth can be estimated. In a non-limiting example, the bandwidth determination unit 933 may be configured to determine the bandwidth of the first communication (e. G., The base layer data segments are received) by sending one or more data segments over a first communication connection The total available network bandwidth can be estimated based on the connection. In the above example, the bandwidth determination unit 933 periodically estimates the total available network bandwidth and uses a predetermined number of moving average (MA) values of previously estimated total available bandwidths as the total available bandwidth, Bandwidth < / RTI >

In the above embodiment, the base layer (BL) access unit 931 is configured to determine whether the base layer data segments are based on one or more of a variety of factors, such as the server (e.g., (E. G., Limiting or "throttling") the rate that is transmitted by the base station (e. Examples of such factors are: (a) the total network bandwidth available for transmission of the requested digital content (e.g., as determined by bandwidth determination unit 933); And (b) the buffer 912 in the storage unit 910 of the client 131 (e.g., as determined by the buffer availability determination unit 934). In a non-limiting example, the base layer access unit 931 is configured to determine the number of base layer segments B ₀ , B ₁ , B ₂ , ..., and B _N-1 to be inversely proportional to the fitness of the buffer 912 And may be configured to limit the transmission rate.

In one embodiment, base layer access unit 931 may be configured to limit the transmission rate by using one of a variety of pacing schemes such as the ACK pacing scheme described in conjunction with FIG. 7A. In a non-limiting example, the base layer access unit 931 receives a response to the successful reception of TCP ACKs (i.e., base layer data segments B ₀ , B ₁ , B ₂ , ..., and B _N-1 ) (TCP ACKs transmitted from the client 131 to the server 110) are generated and transmitted to the server 110 from the client 131. The transmission rate may be indirectly limited by adjusting the rate at which the TCP ACKs are generated and transmitted from the client 131 to the server 110. Additional detail items related to the base layer access unit 931 are described in conjunction with FIGS. 10 and 11.

In one embodiment, enhancement layer access unit 932 may include one or more enhancement layer data segments (e.g., first enhancement layer data segments E ₀ , E ₁ , E ₂ , ...) based on one or more factors. ., _{N -1,} and E) and a second whether received from the enhancement layer data segment _{(E '0, E' 1} , E '2, ..., and E' _N-1)) which the server (110 in) Or < / RTI > Examples of such factors include (a) the total network bandwidth available for transmission of the requested digital content (e.g., as determined by the overall bandwidth determination unit 833); And (b) the amount of network bandwidth allocated for transmission of the base layer data segments (B ₀ , B ₁ , B ₂ , ..., and B _N-1 ) (B ₀ , B ₁ , B ₂ , ..., and B _N-1 ) as limited or "throttled" by the base layer access unit 831 But are not limited to. Additional technical details relating to the enhancement layer access unit 932 are described in conjunction with FIGS. 12 and 13. FIG.

10 is a detailed block diagram illustrating an embodiment of a base layer (BL) access unit 931 shown in FIG. 10, the base layer access unit (931) comprising: a server (e.g., server 110 of FIG. 1) a set of the base layer segments from (e.g., base layer segment of Fig. 3 (B ₀ A bandwidth (BW) allocation unit 1010 configured to determine a network bandwidth (i.e., a transmission rate) for transmission of a plurality of data streams (e.g., B ₁ , B ₂ , ..., and B _{N -1} ) And a throttle configured to limit or throttle the rate at which a series of base layer segments (B ₀ , B ₁ , B ₂ , ..., and B _N-1 ) are transmitted from the server 110 based on the determined network bandwidth. Ring unit 1020 as shown in FIG.

In one embodiment, bandwidth allocation unit 1010 receives a set of base layer segments (B ₀ , B ₀ ) from server 110 based on buffer fullness, e.g., as determined by the buffer integrity determination unit of FIG. B ₁ , B ₂ , ..., and B _N-1 ). In a non-limiting example, the bandwidth allocation unit 1010 may be configured to determine the network bandwidth according to the following equation:

BW _BL = E _BL +? (Equation 1)

Here, "BW _BL " represents the network bandwidth allocated for the transmission of a series of base layer segments (B ₀ , B ₁ , B ₂ , ..., and B _N-1 ) from the server 110 to the client 131 indicates, "E _BL" is a set of the base layer segment _{(B 0, B 1, B} 2, ..., and B _N-1) indicates the encoding rate of, "α" is the storage unit of the client 131 ( Lt; / RTI > is a throttling parameter that can be determined and dynamically adjusted based on the fitness of the buffer 912 in the memory (e. G.

In one embodiment, the bandwidth allocation unit 1010 may be configured to determine the throttling parameter a in inverse proportion to the fitness of the buffer 812. In a non-limiting example, the throttling parameter a may be determined according to the following equation:

(수학식 2)

(2)

Here, "α" denotes a throttling Parameters, "BW _total" represents the total network bandwidth available for transmission of the digital content, "E _BL" is the base layer data segment _{(B 0, B 1, B} 2, ..., and B _N-1 ), "lambda" represents a predetermined constant, and "b" represents buffer poolness.

Figure 11 illustrates a graph for determining throttling parameters from buffer pulses. 11, the graph 1100 includes first and second graphs 1110 and 1120, which have a constant "[lambda]" with different values, Are the graphs of the throttling parameter "a" The first graph 1110 is graphically displayed by setting "BW _total - BW _BL " and "λ" at 10 Mbit / sec and 1/2 respectively and the second graph 1120 at 10 Mbit / sec and 1/6 (I.e., the first graph 1110 is plotted with a larger "? &Quot; than the second graph 1120). 11, the value of the throttling parameter "b" in the first graph 1110 changes more rapidly as the buffer clearance "b" changes relative to the second graph 1120 (i.e., The magnitude of the constant "?" In equation (2) is proportional to the rate of change of the throttling parameter "b"). The first graph 1110 exhibits a more adaptive but less stable adjustment scheme than the second graph 1120. [

In both graphs 1110 and 1120, when the buffer 912 in the storage unit 910 of the client 131 is nearly or completely empty, a higher level (E.g., expressed in bits per second) are allocated for transmission of the base layer data segments (B ₀ , B ₁ , B ₂ , ..., and B _N-1 ). Further, in both graphs 1110 and 1120, a lower level transmission rate or network bandwidth may be used for the base layer data segments B ₀ , B ₁ , B ₂ , ..., And B _N-1 ), so that more network bandwidth is allocated for the first enhancement layer data segments (E ₀ , E ₁ , E ₂ , ..., and E _{N -1} ) and / Is assigned to the layer data segments (E ' ₀ , E' ₁ , E ' ₂ , ..., and E' _{N -1} ), thereby improving the quality of the digital content being played back.

Referring again to FIG. 10, the throttling unit 1020 includes a server 110 and a server 110 to limit the transmission rate of the base layer segments (B ₀ , B ₁ , B ₂ , ..., and B _{N -1} ) Lt; / RTI > In one embodiment, the throttling unit 1020 is operable to determine the number of base layer segments (B ₀ , B ₁ , B ₂ , ..., and B _N-1 ) in the sequence, as determined by the bandwidth allocation unit 1010 In response to successful receipt of a series of TCP ACKs (i.e., at least a portion of base layer data segments (B ₀ , B ₁ , B ₂ , ..., and B _N-1 ) based on the network bandwidth for transmission And TCP ACKs sent from the client 131 to the server 110). In a non-limiting example, the throttling unit 1020 may be configured to determine the transmission rate of the base layer data segments (B ₀ , B ₁ , B ₂ , ..., and B _N-1 ) by the bandwidth allocation unit 1010 And may delay or expedite the transmission of TCP ACKs to remain below the determined transmission rate. The technical details necessary to limit or throttle the transmission rate of data segments are known and may be implemented without further explanation in this disclosure.

12 is a detailed block diagram illustrating an embodiment of enhancement layer (EL) access unit 932 shown in FIG. 12, the enhancement layer access unit 832 may receive one or more enhancement layer segments (e.g., the first enhancement layer data segments of FIG. 3) from a server (e.g., server 110 of FIG. 1) _{(E 0, E 1, E} 2, ..., _{N -1,} and E) and a second enhancement layer of the data segment _{(E '0, E' 1} , E '2, ..., and E' _{N - 1)),} the bandwidth assignment unit 1210 configured to determine the network bandwidth (that is, the transmission rate) for transmission; And a scheduling unit 1220 configured to determine which of the one or more enhancement layer segments is to be received from the server 110 based on the determined network bandwidth (and thereby determine the quality of the digital content to be played back) .

In one embodiment, the bandwidth allocation unit 1210 may be configured to determine network bandwidth for transmission of one or more enhancement layer data segments based on one or more of a variety of factors. Examples of such parameters are: (a) the total network bandwidth available for transmission of the requested digital content (e.g., as determined by the bandwidth determination unit 933 of FIG. 9); And (b) the amount of network bandwidth allocated for transmission of a series of base layer data segments (e.g., limited by the base layer access unit 931 of FIG. 9 from the perspective of the buffer 912) But not limited to, the transmission rate of the base layer data segments (B ₀ , B ₁ , B ₂ , ..., and B _N-1 ) as being "throttled.

As a non-limiting example, the bandwidth allocation unit 1210 may be configured to determine the network bandwidth according to the following equation:

BW _EL = BW _total - BW _BL (Equation 3)

"BW _BL " represents a series of base layer data segments (B ₀ , B ₁ ) from the server 110 to the client 131, "BW _total " represents the total network bandwidth available for transmission of the requested digital content, , B ₂ , ..., and B _N-1 ).

In one embodiment, bandwidth allocation unit 1210 may be configured to periodically determine network bandwidth for each of a predetermined series of time periods. 13A and 13B are diagrams illustrating the determination of network bandwidth and the selection of one or more enhancement layer data segments. 13A and 13B, in a non-limiting example, the bandwidth allocation unit 1210 may determine the network bandwidth to be allocated for time intervals between 2 and 8 seconds for a time interval between 0 and 2 seconds . In addition, the bandwidth allocation unit 1010 can determine the network bandwidth to be allocated for time intervals between 10 and 16 seconds for a time interval between 8 and 10 seconds.

12, in one embodiment, the scheduling unit 1220 is configured to: (a) determine which of the enhancement layer segments will be forwarded from the server 110 in the future based on the network bandwidth determined by the network allocation unit 1210 Select whether to receive; And (b) generate and transmit HTTP GET request (s) for selected ones of the enhancement layer data segments. Referring again to Figures 13A and 13B, in a non-limiting example, the scheduling unit 1220 is provided with network bandwidth as determined by the bandwidth allocation unit 1210 for a time interval between 0 and 2 seconds, (And thus, determines the quality of the digital content to be played during time intervals between 2 and 8 seconds) during which time intervals between 2 and 8 seconds. In the example in Figs. 13a and 13b embodiment, a portion of the first enhancement layer data segment (E _1, E _2, and E ₃₎ and the second enhancement layer data segment _{(E '1, E' 2} , and E _'3) Or all may be selected to be received from the server 110 for time intervals between 2 and 8 seconds.

13A, if the network bandwidth allocated by the bandwidth allocation unit 1210 is sufficient to allow reception of three enhancement layer data segments, then the scheduling unit 1220 may determine that the time interval between 2 and 8 seconds while can be selected to receive one of the enhancement layer data segment (E _1, E _2, and E _3). Alternatively, as shown in FIG. 13B, the scheduling unit 1220 may generate the first enhancement layer data segments (E ₁ and E ₂ ) and the second enhancement layer data segment (E ₁ and E ₂ ) during time intervals between 2 and 8 seconds E ' ₁ ). The example illustrated in FIG. 13A may provide a relatively stable quality of digital content as compared to the example illustrated in FIG. 13B, while the example illustrated in FIG. 13B may be at least temporarily higher in level than the example illustrated in FIG. It is possible to provide digital contents in quality.

According to some embodiments, FIG. 14 is a flow diagram of a method performed by a client, for example, client 131, to divide network bandwidth for base layer and enhancement layer data segments. 14, in step 1410 performed by, for example, the buffer availability determination unit 934 of the client 131, a series of packets received from the server (e.g., the server 110 of FIG. 1) (E.g., buffer 912 of FIG. 9) for temporarily storing a base layer data segment and one or more enhancement layer data segments. For example, in step 1420 performed by the bandwidth decision unit 933 of the client 131, an estimate of the total network bandwidth available for the delivery of a series of base layer segments and one or more enhancement layer segments.

For example, in step 1430 performed by the base layer access unit 931 of the client 131, the transmission rate of a sequence of base layer data segments may be determined by the level of privacy of the buffer 912 by communicating with the server 110, / RTI > and / or indirectly based on the total available network bandwidth. For example, the temporal spacing of a series of acknowledgments (ACKs) to be sent to the server 110 in response to successful receipt of a series of base layer data segments may be modulated by the base layer access unit 931. [ For example, in step 1440 performed by the enhancement layer access unit 932 of the client 131, it is determined which of the one or more enhancement layer data segments is to be received based on the integrity level of the buffer 912 and / Is determined based on the network bandwidth.

While this disclosure has been shown and described with respect to preferred embodiments, those skilled in the art will recognize that various changes and modifications can be made without departing from the spirit and scope of the invention as defined in the appended claims. Moreover, although the methods and systems of the present disclosure have been described above with regard to specific embodiments, some or all of the elements or operations thereof may be implemented using a computer system having a general purpose hardware architecture. Figure 15 illustrates a block diagram of a computing system architecture that may be used to implement one or more of the components and processes thereof described herein. 15, in one implementation, a hardware system 1500 includes a processor 1502, a cache memory 1504, and one or more software applications / drivers (not shown) associated with the functions described herein. . ≪ / RTI >

In addition, the hardware system 1500 may include a high performance input / output (I / O) bus 1506 and a standard I / O bus 1508. Host bridge 1510 couples processor 1502 to high performance I / O bus 1506 while I / O bus bridge 1512 couples two busses 1506 and 1508 to each other. System memory 1514 and network / communication interface 1516 are coupled to bus 1506. The hardware system 1500 may further include a video memory (not shown) and a display device (not shown) coupled to the video memory. Mass storage 1518 and I / O ports 1520 are coupled to bus 1508. The hardware system 1500 may optionally include a keyboard (not shown) and a pointing device (not shown). It may also include a display device (not shown) coupled to the standard I / O bus 1508. Collectively, these components include, but are not limited to, general purpose computer systems based on one or more processors manufactured by Intel Corporation of Santa Clara, California, as well as any other suitable processor And is intended to represent a broad category of computer hardware systems.

The components of the hardware system 1500 are described in further detail below. In particular, network interface 1516 provides communication between any of a wide variety of networks, such as hardware system 1500 and Ethernet (e.g., IEEE 802.3) networks. In the case of the server 110 (Figures 1 and 2), the network interface 1516 is connected to the communications network 120 (e.g., the network 130) connected to the clients 130 to allow the hardware system 1500 to communicate with the clients 130 ) And the hardware system 1500. [ Similarly, in the case of client 130 (FIGS. 1, 4 and 8), network interface 1516 provides communication system 120 with server 110 to enable hardware system 1500 to communicate with server 110. [ Lt; / RTI > Mass storage 1518 provides persistent storage of data and programming instructions for performing the aforementioned functions implemented in clients 130 or server 110 while system memory 1514 (e.g., DRAM) provides temporary storage of data and programming instructions when executed by the processor 1502. < RTI ID = 0.0 > I / O ports 1520 are one or more serial and / or parallel communication ports that provide for communication between additional peripheral devices that may be coupled to hardware system 1500.

The hardware system 1500 may include various system architectures. In addition, various components of the hardware system 1500 may be rearranged. For example, the cache 1504 may be on-chip with the processor 1502. Alternatively, the cache 1504 and the processor 1502 may be packaged together as a " processor module ", and the processor 1502 is referred to as a "processor core ". Furthermore, certain implementations of the present disclosure may or may not include all of the above components. For example, peripheral devices shown as being coupled to the standard I / O bus 1508 may be coupled to the high performance I / O bus 1506. Additionally, in some implementations, only a single bus may be present and the components of the hardware system 1500 are coupled to a single bus. In addition, the hardware system 1500 may include additional components such as additional processors, storage devices, or memories. As discussed below, in one embodiment, the operations of the system including the system 100 for providing the digital content described herein may be implemented as a series of software routines executed by the hardware system 1500 have. These software routines include a plurality or series of instructions to be executed by a processor in a hardware system, such as processor 1502. Initially, a series of commands are stored on a storage device, such as mass storage 1518. However, a series of instructions may be stored on any suitable storage medium such as a diskette, CD-ROM, ROM, EEPROM, and the like. Also, the series of commands need not be stored locally, but may be received from a remote storage device, such as a server on the network, via network interface 1516. [ The instructions are copied into the memory 1514 from a storage device, such as mass storage 1518, and then accessed and executed by the processor 1502. [

The operating system manages and controls the operation of the hardware system 1500, including input and output of data to and from software applications (not shown). The operating system provides an interface between the software applications running on the system and the hardware components of the system. According to one embodiment of the present invention, the operating system is a Windows® operating system provided by Microsoft Corporation of Redmond, Washington. However, the present invention may be used with other suitable operating systems such as the Apple Macintosh operating system, UNIX operating system, LINUX operating system, etc., provided by Apple Computer Inc. of Cupertino, CA.

The objects of the disclosed subject matter and corresponding portions of the detailed description are presented in terms of software, algorithms, or symbolic operational representations of data bits in computer memory. An algorithm refers to one or more operations or steps that result in a desired result, as the term is used herein and as generally used. Operations or steps may be those requiring physical manipulations of physical quantities or features. Typically, such quantities or features take the form of optical, electrical, or magnetic signals that can be stored, transmitted, combined, compared, or otherwise manipulated. For convenience, such signals are referred to herein as bits, data, values, symbols, characters, items, numbers, streams,

It should be borne in mind, however, that all of these and similar items will be associated with appropriate physical quantities and features, and are merely convenient labels applied to such quantities and features. Computing, "" determining, "" determining, "" displaying, "" receiving, "" modulating, "" generating, "" Quot ;, " coupled ", "applying "," maximizing ", "minimizing ", and the like refer to data expressed in physical and electrical quantities in registers and memories of a computer system, Registers, or other such information, storage, transmission, or other data similarly represented as physical quantities within display devices.

It should also be appreciated that the software implementation aspects of the disclosed subject matter are typically stored on some form of program storage medium or implemented on some type of transmission medium. Program storage media may be any suitable medium capable of storing data or signals such as hard drives, tapes, CD-ROMs, DVDs, Blu-ray, RAM, ROM, flash memory, Similarly, the transmission medium may be a twisted wire pair, a coaxial cable, an optical fiber, or any other suitable transmission medium known in the art. The disclosed subject matter is not limited by these aspects of any given embodiment.

While the embodiments of the present disclosure may be susceptible to various modifications and alternative forms, specific embodiments have been shown by way of example in the drawings and are herein described in detail. It should be understood, however, that the embodiments of the present disclosure are not intended to be limited to the specific forms disclosed. Rather, the embodiments are intended to cover all modifications, equivalents, and alternatives falling within the spirit and scope of the disclosure as defined by the following appended claims.

Claims (25)

A method for requesting digital content,
Establishing a first communication connection with the server;
Establishing a second communication connection with the server;
Sending a first request for a plurality of base layer data segments over the first communication connection to the server;
Transmitting one or more second requests for one or more enhancement layer data segments over the second communication connection to the server, wherein the at least one enhancement layer data segment and at least a portion of the plurality of base layer data segments are associated with the digital content Lt; RTI ID = 0.0 > of: < / RTI > The method according to claim 1,
Receiving and decoding the one or more enhancement layer data segments with the at least a portion of the plurality of base layer data segments to provide a decoded stream of the encoded stream. The method according to claim 1,
Wherein the first and second communication connections are transport layer connections each providing ordered, error-checked, and / or reliable delivery of the base layer and / or enhancement layer data segments. The method according to claim 1,
Wherein sending the first request comprises sending to the server a request to transmit the plurality of base layer data segments over the first communication connection in a progressive streaming mode. 5. The method of claim 4,
Storing the base layer and enhancement layer data segments in a buffer;
Determining a fullness level of the buffer; And
Communicating with the server to limit the transfer rate of the plurality of base layer data segments based on a level of integrity of the buffer
≪ / RTI > 6. The method of claim 5,
Wherein communicating with the server comprises modulating a temporal spacing between a plurality of acknowledgments (ACKs) to be sent to the server, each of the plurality of acknowledgments responding to successful receipt of at least some of the plurality of base layer data segments Transmitted < / RTI > 6. The method of claim 5,
Wherein communicating with the server comprises communicating with the server to limit the transfer rate in inverse proportion to the level of integrity of the buffer. 3. The method of claim 2,
Wherein transmitting the one or more second requests comprises transmitting the one or more second requests over the second communication connection based on an adaptive streaming scheme. 9. The method of claim 8,
Storing the base layer and enhancement layer data segments in a buffer;
Estimating an available network bandwidth;
Determining one or more enhancement layer data segments to be subsequently received based on the estimated available network bandwidth and the level of integrity of the buffer
≪ / RTI > 10. The method of claim 9,
Wherein estimating the available network bandwidth comprises estimating an available network bandwidth using the first communication connection. 11. The method of claim 10,
Wherein determining the one or more enhancement layer data segments to be subsequently received comprises determining a network bandwidth to be allocated to the second communication connection based on the estimated available network bandwidth. A device for receiving digital content, the device comprising:
A communication unit configured to receive a plurality of base layer data segments and one or more enhancement layer data segments; And
And a buffer configured to temporarily store the base layer and enhancement layer data segments,
Wherein the communication unit is further configured to allocate available network bandwidth to at least one of the plurality of base layer data segments and the one or more enhancement layer data segments based on a level of integrity of the buffer. 13. The communication system according to claim 12,
A buffer fullness determination unit configured to determine the fullness level of the buffer; And
And a base layer access unit configured to communicate with the server to limit the transfer rate of the plurality of base layer data segments based on the level of integrity of the buffer. 13. The communication system according to claim 12,
A buffer fullness determination unit configured to determine the fullness level of the buffer; And
And an enhancement layer access unit configured to determine one or more enhancement layer data segments to be subsequently received based on the level of integrity of the buffer. 14. The method of claim 13,
Wherein the base layer access unit is configured to modulate temporal spacing between a plurality of acknowledgments (ACKs) to be transmitted to the server, each of the plurality of acknowledgments responding to successful receipt of at least some of the plurality of base layer data segments Lt; / RTI > 14. The method of claim 13,
Wherein the base layer access unit is configured to communicate with the server to limit the transfer rate in inverse proportion to a level of integrity of the buffer. 13. The method of claim 12,
Wherein the communication unit is configured to establish a first communication connection for receiving the plurality of base layer data segments and a second communication connection for receiving the one or more enhancement layer segments. 18. The communication system according to claim 17, wherein the communication unit
And a bandwidth determination unit configured to estimate an available network bandwidth using the first communication connection. A method for receiving digital content,
Determining a level of integrity of a buffer for storing a plurality of base layer data segments received from the server and one or more enhancement layer data segments; And
Allocating available network bandwidth to at least one of the plurality of base layer data segments and the one or more enhancement layer data segments based on the level of integrity of the buffer. 20. The method of claim 19, wherein allocating the available network bandwidth comprises:
Further comprising communicating with the server to limit the transfer rate of the plurality of base layer data segments based on the level of integrity of the buffer. 20. The method of claim 19, wherein allocating the available network bandwidth comprises:
Further comprising determining one or more enhancement layer data segments to be subsequently received based on a level of integrity of the buffer. 22. The method of claim 21,
Wherein communicating with the server comprises modulating a temporal spacing between a plurality of acknowledgments (ACKs) to be sent to the server, each of the plurality of acknowledgments responding to successful receipt of at least some of the plurality of base layer data segments The method comprising the steps of: 23. The method of claim 22,
Wherein communicating with the server comprises communicating with the server to limit the transfer rate in inverse proportion to the level of integrity of the buffer. 20. The method of claim 19,
Further comprising establishing a first communication connection for receiving the plurality of base layer data segments and a second communication connection for receiving the one or more enhanced layer data segments. 25. The method of claim 24,
Further comprising estimating an available network bandwidth using the first communication connection.

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