The present invention relates to a method for processing a channel change request in a television system operating according to the IP protocol.
This application claims the benefit, under 35 U.S.C.§119 of EP Patent Application 0853804, filed Jun. 9, 2008.
In television systems operating according to IP (Internet Protocol) protocol, the video streams are generally transmitted to subscribers via a broadband connection. More specifically, a transmission signal is transmitted to digital decoders (Set Top Box) of subscribers via an access network and DSL (Digital Subscriber Line) modems. This transmission signal is decoded then converted into standard television signals by the digital decoder of the subscriber.
To change channel, the subscriber presses the programme keys P+ or P− of the digital decoder remote control. The P+ key enables incrementing the channel number currently being viewed and the P− key enables decrementing it. In response to a channel change request, the digital decoder transmits to the access network a physical channel change request via its DSL modem. Typically this request is carried out using the IGMP (Internet Group Management Protocol) protocol. In this case, the physical channel change request is a subscription request. The digital decoder then sends as a subscription parameter the IP address of the channel that it wants to receive.
To avoid this overloading of the access network, it is known in the art to not transmit all the physical channel change requests. This operating mode is shown in
The operating mode described with respect to
The present invention enables all or some of the previously cited problems to be overcome.
For this purpose, the present invention proposes a method for processing a channel change request in a television system on IP comprising a digital decoder connected to a television and an access network, remarkable in that, in response to said channel change request, the digital decoder carries out the following steps:
a) transmits to the access network a physical channel change request corresponding to the channel change request, and triggers a timeout period of Ttempo,
b) if a new channel change request is received by the digital decoder during said timeout period, it triggers a new timeout period of Ttempo, and
c) transmits to the access network a physical channel change request corresponding to the channel change request as soon as the new timeout period has ended or, if a new channel change request is received by the digital decoder during the new timeout period, it restarts at step b).
Hence in the case of burst zapping, a physical channel change request is transmitted only for the first and last channel change requests of the burst. The physical channel change request corresponding to the first channel change request is transmitted upon reception of the first channel change request by the decoder and the physical channel change request corresponding to the channel change request is transmitted upon the expiration of the timeout period of the last channel change request. In the case of simple zapping, the physical channel change request is transmitted immediately after the reception of the channel change request.
Hence the present invention enables both to avoid overloading the access network in the case of burst zapping and to not penalise the system reactivity time in cases of simple zapping.
According to a preferred embodiment, the decoder also transmits, during step a), a control message to display on the television information relating to the channel requested to inform the subscriber that his channel change request was indeed received by the decoder.
Likewise, according to another preferred embodiment, the decoder also transmits, during step b), a control message to display on the television information relating to the channel newly requested.
The invention also relates to a digital decoder for a television system on IP, said digital decoder is connected to a television and an access network and comprises the means to process channel change requests able to implement the aforementioned method.
The invention will be better understood, and other purposes, details, characteristics and advantages will appear more clearly over the following detailed explanatory description of a preferred embodiment of the invention, with reference to annexed diagrammatical drawings among which:
The method shown in
The decoder then tests, during a step referenced as 410, if it has received a channel change request from the remote control of the decoder. In the negative, it waits for a channel change request. In the affirmative, the decoder implements step 420. In this step, the decoder immediately transmits a physical channel change request, for example in the form of a subscription request in the case of IGMP protocol, to the access network and triggers a timeout period with a duration of Ttempo. Preferably, the decoder also commands, through the transmission of a control message, the display of information relating to the channel change request on the screen of the television connected to the decoder to inform the subscriber that his channel change request has indeed been received by the decoder. This transmission shown by step 430 in
The following steps, 440 and 450, are test steps to determine if the decoder has received a new channel change request during the timeout period. If the timeout period expires without a new change request being received, there is a return to step 410. However, if a new channel change request is received before the end of the timeout period, there is a passage to step 460.
At step 460, the decoder triggers a new timeout period. Preferably, the decoder also commands, through the transmission of a control message, the display of information relating to the new channel change request on the screen of the television connected to the decoder in a step 470. This step can be carried out at the same time as step 460.
The following steps, 480 and 490, are test steps to determine if the decoder has received a new channel change request during this new timeout period. If this new timeout period expires, without a new change request being received, a physical channel change request is transmitted to the access network in step 500 and if not it is restarted at step 460.
Finally, after step 500, it is restarted at step 410.
The results of this method are shown in
In response to a burst of channel change requests (case where the time interval between two consecutive requests is less than Ttempo), the decoder transmits a physical channel change request for the first and last channel change requests of the burst. The physical channel change request corresponding to the first channel change request is transmitted immediately after the reception of the first channel change request. The physical channel change request corresponding to the last channel change request is transmitted at the end of a timeout period of the last channel change request. Hence, if these results are compared to those of
In response to a plurality of simple channel change requests (case where the time interval between two consecutive requests is greater than Ttempo), the decoder transmits a physical channel change request for each of the channel change requests and this physical channel change request is transmitted immediately after reception of the channel change request. Hence, if these results are compared with those of
The duration of the timeout period employed in this method is comprised between 300 ms and 700 ms. It is preferably in the order of 500 ms.
Though the invention has been described in relation to a specific embodiment, it is evident that this is in no way restricted and that it comprises all technical equivalents of the steps described as well as their combinations if these enter into the scope of the invention.
Number | Date | Country | Kind |
---|---|---|---|
08 53804 | Jun 2008 | FR | national |
Number | Name | Date | Kind |
---|---|---|---|
7685616 | Virdi et al. | Mar 2010 | B2 |
20040194134 | Gunatilake et al. | Sep 2004 | A1 |
20070107024 | Versteeg et al. | May 2007 | A1 |
20070107026 | Sherer et al. | May 2007 | A1 |
20080244679 | Sukumar et al. | Oct 2008 | A1 |
20080288979 | Smoyer et al. | Nov 2008 | A1 |
20090031392 | VerSteeg et al. | Jan 2009 | A1 |
20100017463 | Horn et al. | Jan 2010 | A1 |
Number | Date | Country |
---|---|---|
4304365 | Aug 1994 | DE |
0821523 | Jan 1998 | EP |
2784253 | Apr 2000 | FR |
Entry |
---|
Scott Shoaf et al. “IGMP Capabilities in Broadband Network Architectures” Internet Citation, Nov. 26, 2007 XP002459905 Nov. 26, 2007, *p. 5, *p. 8-11*, *p. 17*. |
Search Report dated Oct. 10, 2008. |
Number | Date | Country | |
---|---|---|---|
20100100913 A1 | Apr 2010 | US |