KR20080059866A - Method for receiving efficient video using received signal strength notification mechanism in iptv environment - Google Patents

Abstract

A method for transmitting contents data according to signal strength in a mobile IPTV environment is provided to remarkably improve the service quality of IPTV by varying the bit rate of contents, which are transmitted to a mobile terminal, according to the mobile terminal's RSS(Received Signal Strength) so as to provide a seamless service to the user in a mobile IPTV environment. A media server transmits a video to a mobile terminal at a predefined bit rate initially(S11). If a notification message is received from the mobile terminal(S12), the media server judges whether or not the received notification message is bit rate information(S13). If not, the media server temporarily stops video transmission(S14). In case the received notification message is bit rate information, however, the media server transmits a video source having the nearest value to the received bit rate information among its own bit rate video sources(S15). Then the media server confirms whether the transmission of the contents data is completed(S16).

Description

Method of transmitting content data according to signal strength in mobile adaptive environment {METHOD FOR RECEIVING EFFICIENT VIDEO USING RECEIVED SIGNAL STRENGTH NOTIFICATION MECHANISM IN IPTV ENVIRONMENT}

1 is a network configuration diagram for a general IPTV service,

2 is a flowchart illustrating a process of a mobile portable terminal in a method of transmitting content data according to signal strength in a mobile adaptive environment of the present invention;

 3 is a flowchart illustrating a process performed by a media server in response to receiving the notification message transmitted in FIG. 2 according to an embodiment of the present invention.

* Explanation of symbols in the drawing 8

10: IPTV Server 20: Streaming Server

30: content providing server 40: access network

41: base station 42: access point

43: LAN 41 ~ 43: subscriber connection

50: subscriber device

The present invention relates to content data transmission according to reception intensity in a mobile IPTV environment (hereinafter, referred to as 'IPTV'). More particularly, the present invention converts a data transmission rate according to a reception signal strength of a mobile IPTV environment to transmit content data. It is related to a method of transmitting content data according to signal strength in an environment.

1 is a diagram illustrating a system configuration for a general IPTV service.

As shown in FIG. 1, the system for IPTV service includes an IPTV server 20 as a service provider (SP) for performing subscriber access management, content data transmission control, and the like for providing an IPTV service, and an IPTV server. Streaming server (SS) 20 which encodes and transmits the content transmitted to the user as streaming data under the control of 10, and a content providing server as a content provider (CP) for supplying content. A server system comprising 30, a PSTN for supporting network communication by IP, a mobile communication network, and the like, and a subscriber connection unit for providing access points such as a base station 41, an access point 42, a LAN 43, and the like. And a subscriber device 50 such as a TV, a mobile terminal, a computer, and the like, which receive IPTV service through the subscriber connection unit.

The IPTV service provided with the system configuration as described above is a level of quality of service (QoS) required to allow a TV receiver to watch content transmitted through a wired or wireless network using an internet protocol (IP). It provides multimedia services such as television / video / audio / text / data delivered over IP-based networks that provide quality of experience, information protection, interaction and reliability. The conventional IPTV service having the above-described configuration uses a method of transmitting content encoded at one bit rate when transmitting content data.

However, the mobile environment is characterized by low communication bandwidth and frequent fluctuations in the signal strength received from the base station or access point due to the interference and influence of the surroundings. In addition, a change in signal strength occurs due to the mobility of the user. In the case of frequent signal intensity fluctuations due to the mobility of the user, especially when transmitting a high bit rate content when the signal strength is low, the reception screen is interrupted due to a high error rate and a loss rate.

That is, in the case of the conventional IPTV service system as described above, since the transmitted content data is encoded at one bit rate, it is impossible to properly cope with the mobile propagation environment and the user's mobile environment, thereby degrading the service quality of the IPTV. Has the problem.

Accordingly, the present invention is to solve the above-mentioned problems of the prior art, the mobile terminal after storing the video content and multiplexer of different bit rates in a server (hereinafter referred to as a media server) for storing the content data for providing the IPTV service The purpose of the present invention is to provide a method of transmitting content data according to signal strength in an environment in which a mobile server that transmits content having an appropriate bit rate by notifying the media server whenever a portable terminal detects a change in signal strength at present. It is done.

Content data transmission method according to the signal strength in the mobile adaptive environment of the present invention for achieving the above object, if the mobile portable terminal detects the received wireless signal strength and exceeds the allowable change value to the notification message to the media server Receiving signal strength change notification process; And a transmission bit rate conversion process of receiving, by the media server, the received signal strength change value included in the notification message, converting the content data into a content data having a bit rate suitable for the sea reception strength, and transmitting the content data to the mobile portable terminal. do.

The received signal strength change notification process may include: a signal strength detection process of detecting, by the mobile portable terminal, the strength of a received wireless signal to store a current received signal strength and then detecting a difference from a previous current received signal strength; A comparison process of comparing a difference value of the received signal strength detected in the signal strength detection process with a preset threshold value; A bit rate calculation step of calculating a corresponding receivable bit rate when a difference value of the received signal strength detected as a result of the comparison in the comparison step is out of a preset threshold value; And a reception bit rate notification step of notifying the media server of the annual result value of the bit rate calculation process by a notification message.

The transmission bit rate conversion step may include: a content data selection step of selecting content data having a bit rate closest to a receivable bit rate of the mobile terminal included in the notification message; And a data rate conversion process of detecting a region of the content data previously transmitted from the selected content data and transmitting the region from a corresponding region in a streaming manner.

Hereinafter, with reference to the accompanying drawings showing a preferred embodiment of the present invention will be described in more detail the present invention.

FIG. 2 is a flowchart illustrating a process in which a mobile portable terminal calculates a bit rate that can be transmitted according to a received signal strength and notifies the media server as a notification message in a method of transmitting content data according to signal strength in an environment.

As shown in FIG. 2, the mobile handheld terminal transmits a notification message to the media server based on the signal strength at the beginning stages of pRSS (existing reception strength value), cRSS (current reception strength value), and DIFF (receipt strength change amount). ) Is initialized (S1).

As the initialization process of S1 is performed, the mobile portable terminal continuously updates the cRSS to the current reception intensity and calculates a DIFF (S2).

While performing the S2 process, the mobile portable terminal determines whether the calculated DIFF is greater than a predefined threshold THdiff (S3).

If the calculated DIFF is not larger than the predefined threshold THdiff as a result of the determination of S3, the process is repeated by moving S1.

On the contrary, if the calculated DIFF is larger than the predefined threshold THdiff, the S3 process judges that a sufficiently large signal strength change has occurred, and compares the currently changed signal strength value with the minimum allowable threshold value THmin. S4).

As a result of the comparison of the S4 process, if the current signal strength is smaller than the minimum allowable signal strength, the video pause control message is transmitted to the media server and monitored and waited until the signal strength is good (S5).

On the contrary, if the current signal strength is greater than the minimum allowable signal strength, the new video bit rate crate is estimated and the estimated value is transmitted to the media server (S6).

After the process S6, it is determined whether the reception service of the content data is terminated, if the process is terminated, and if it is not terminated, the process moves to the process S1 and repeats the process (S7).

Next, the processing of the media server will be described.

3 is a flowchart illustrating a process performed by a media server in response to receiving the notification message transmitted in FIG. 2 according to an embodiment of the present invention.

As shown in FIG. 3, the media server initially transmits video at a predefined bit rate (S11).

The media server waits for a notification message sent from the receiving mobile portable terminal and receives the message (S12). It determines whether the received notification message is bit rate information (S13).

If the result of the determination in step S13 is that the type of the received notification message is not the bit rate information, the message processing procedure is performed accordingly. Also, if the type of the received message is not the bit rate information, it is determined that the received signal strength of the terminal is not sufficient and the video is transmitted. The process of pausing the process is performed (S14).

In contrast, if the type of the notification message received as a result of the determination in step S13 is a bit rate information, the video source (content data) having the closest value to the received bit rate information among various bit rate video sources currently owned by the media server is transmitted. (S15).

If it is determined that the transmission of the content data has ended, the process moves to step S11 to repeat the process, and if so, the process ends (S16).

As described above, the present invention enables the media server to measure the exact available bandwidth that can be transmitted to the mobile handheld terminal so as to efficiently transmit the content data (video source).

Meanwhile, in the above description of the present invention, specific embodiments have been described, but various modifications may be made without departing from the scope of the present invention. Therefore, the scope of the invention should be determined by the claims rather than by the described embodiments.

In the foregoing description of the present invention, specific embodiments have been described, but various modifications may be made without departing from the scope of the present invention. Therefore, the scope of the present invention should be determined by the claims rather than by the described embodiments.

The present invention described above significantly improves the quality of service of IPTV by allowing the user to receive a seamless service by varying the bit rate of the content transmitted to the mobile terminal according to the signal reception strength of the mobile terminal in the mobile IPTV environment. It provides an effect.

Claims (3)

A received signal strength change notification process of notifying the media server by a notification message when the mobile portable terminal detects the received wireless signal strength and exceeds the allowable change value; And a transmission bit rate conversion process of receiving, by the media server, the change value of the received signal strength included in the notification message, converting the content data into a content data having a bit rate suitable for the corresponding reception strength, and transmitting the changed content data to the mobile portable terminal. Mobile data transmission method according to the signal strength in the environment. The method of claim 1, wherein the received signal strength change notification process, A signal strength detection process of detecting, by the mobile portable terminal, the strength of the received wireless signal to store the current received signal strength and then detecting a difference from the previous current received signal strength; A comparison process of comparing a difference value of the received signal strength detected in the signal strength detection process with a preset threshold value; A bit rate calculation step of calculating a corresponding receivable bit rate when a difference value of the received signal strength detected as a result of the comparison in the comparison step is out of a preset threshold value; And a received bit rate notification process of notifying a media server of an annual result value of the bit rate calculation process by a notification message. The method of claim 1 or 2, wherein the transmission bit rate conversion process, A content data selection process of selecting content data having a bit rate closest to a receivable bit rate of the mobile terminal included in the notification message; A data rate conversion process of detecting an area of content data previously transmitted from the selected content data and transmitting the data content in a streaming manner from the corresponding area; .

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