Abstract:
In certain home multimedia networks having a plurality of terminals, there are no provisions for sending error messages when a service cannot be delivered owing to conflicts with another service. The present invention proposes to let the media server of the tuner in such a network provide an image bearing the message and deliver this image to the terminal that otherwise would be left in the dark.

Description:
FIELD OF THE INVENTION 
       [0001]    The present invention is generally directed to digital content distribution, and in particular to error reporting in digital content distribution networks. 
       BACKGROUND OF THE INVENTION 
       [0002]    This section is intended to introduce the reader to various aspects of art, which may be related to various aspects of the present invention that are described and/or claimed below. This discussion is believed to be helpful in providing the reader with background information to facilitate a better understanding of the various aspects of the present invention. Accordingly, it should be understood that these statements are to be read in this light, and not as admissions of prior art. 
         [0003]    The prior art teaches many systems for service delivery, such as for example those described in WO 03/085892 and WO 00/67135. In these systems, a device may notify a user of non-delivery of a service through dedicated error messages. However, as will be seen, there are systems that do not have such messages, in which case these solutions may not be used for such a notification. 
         [0004]      FIG. 1  illustrates an exemplary prior art network that will help present a problem solved by the present invention. The network  100  comprises an access network  110  and a home network  120 . The access network  110 , which may be based on any suitable technology such as for example broadcast satellite or broadband ADSL, is adapted to deliver content, such as broadcast television, to a plurality of home networks  120  (only one home network is shown in the Figure for reasons of clarity.) The content delivered over the access network  110  to the home network  120  is received by a gateway device  130 , hereinafter called “tuner”. The tuner  130  is adapted to select at least one item of content and to deliver it over an internal network  140 , that for example is Ethernet based, to at least one of a plurality of terminals  150 ,  155 . 
         [0005]    The tuner  130  works as a media server towards the terminals  150 ,  155  and is preferably adapted to provide a content service list to them, this service list providing a view on all the content accessible by the tuner  130 . The terminals  150 ,  155  are able to retrieve or receive this list from a media server in the tuner. 
         [0006]    Assume, for example, the first terminal  150  uses a SD&amp;S (Service Description and Selection) protocol to select a service, such as a particular program, from the service list and to request the tuner  130  to deliver the service on the internal network  140 . According to the protocol, the first terminal  150  comprises a RTP (Real Time Protocol) client  151 , the tuner  130  comprises a RTP server  131 , and the terminal  150  sends a IGMP (Internet Group Multicast Protocol) join request on the network, which multicast group address is corresponding to the service; the Multicast group address being indicated in the list. The tuner  130  then accesses the service via the access network  110 . Depending on the technology used in the access network  110 , the access may for example be established by locking to the right frequency or by joining the right multicast group. Once the service has been accessed, the tuner  130  sends the service over the internal network  140 . 
         [0007]    Assume then that the second terminal  155  requests another service, using its RTP client  156  in a similar manner. If this second service is compatible with the first service—i.e. it may be accessed from the access network  110  in parallel with the first service, which may be the case if the services for example share a frequency, or there is enough bandwidth left to retrieve the service and send it over the internal network  140 —then the second service will be delivered to the second terminal  155 . 
         [0008]    However, the second service may also be incompatible with the first service, e.g. if they do not share a frequency or if sufficient bandwidth is lacking. In this case it is not possible to deliver both services and the tuner  130  is left with a choice: either it refuses the request or it accepts the request at the cost of stopping the delivery of the first service to the first terminal  150 . In both cases, a terminal will be left in the dark as to what happened, since the protocol does not provide any error messages. 
         [0009]    It will be appreciated that users would benefit from a solution to this problem. At present, though, no such solutions exist and it is an object of the present invention to provide a solution that enables users be alerted for example when service delivery is impossible for any of the reasons detailed hereinbefore. 
       SUMMARY OF THE INVENTION 
       [0010]    In a first aspect, the invention is directed to a method for delivering error information in a network that comprises an apparatus and a first device. The apparatus receives from the first device a request for a first audiovisual service. In case the first audiovisual service may not be delivered, the apparatus delivers an item of audiovisual content to the first device, the item of audiovisual content being such that it, when rendered to a user, provides to the user error information about the non-delivery of the first service. 
         [0011]    In a first preferred embodiment, the network further comprises at least one second device to which the apparatus delivers a second audiovisual service. If the second audiovisual service is to be refused in order to deliver the first audiovisual service, the apparatus refuses delivery of the second audiovisual service, and delivers an item of audiovisual content to the at least one second device, the item of audiovisual content being such that it, when rendered to a user, provides to the user error information about the non-delivery of the second audiovisual service. It is advantageous that the first audiovisual service and the audiovisual second service are accessed by the apparatus over a second network. 
         [0012]    In a second preferred embodiment, the item of audiovisual content is an image. 
         [0013]    In a third preferred embodiment the first audiovisual service is accessed by the apparatus over a second network. 
         [0014]    In a second aspect, the invention is directed to an apparatus adapted to be connected to a network further comprising a first device. The apparatus comprises an interface adapted to receive from the first device a request for a first audiovisual service; and a processor adapted to, in case the first audiovisual service may not be delivered, deliver an item of audiovisual content to the first device, the item of audiovisual content being such that it, when rendered to a user, provides to the user error information about the non-delivery of the first audiovisual service. 
         [0015]    In a first preferred embodiment, the apparatus is further adapted to be connected to at least one second device and the processor is adapted to deliver a second audiovisual service to the at least one second device; and, if the second service is to be refused in order to deliver the first audiovisual service, refuse delivery of the second audiovisual service, and deliver an item of audiovisual content to the at least one second device, the item of audiovisual content being such that it, when rendered to a user, provides to the user error information about the non-delivery of the second audiovisual service. It is advantageous that the apparatus further comprises a second interface adapted to be connected to a second network and the processor is further adapted to access the first audiovisual service and the second audiovisual service over the second network. 
         [0016]    In a second preferred embodiment, the item of audiovisual content is an image. 
         [0017]    In a third preferred embodiment, the apparatus further comprises a second interface adapted to be connected to a second network and the processor is further adapted to access the first audiovisual service over the second network. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0018]    Preferred features of the present invention will now be described, by way of example, with reference to the accompanying drawings, in which: 
           [0019]      FIG. 1 , already described hereinbefore, illustrates a prior art network; and 
           [0020]      FIG. 2  illustrates an apparatus according to a preferred embodiment of the present invention. 
       
    
    
     DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS 
       [0021]      FIG. 2  illustrates an apparatus according to a preferred embodiment of the present invention.  FIG. 2  only illustrates the apparatus itself, while the objects of  FIG. 1  that are outside the apparatus are not shown, but the same reference numbers will be used for convenience. Furthermore, internal connections are left out of the Figure for the sake of clarity. 
         [0022]    The apparatus, in the present example a tuner  230 , comprises at least a first interface (I/O  1 )  231  for communication with an access network  110  and a second interface (I/O  2 )  232  for communication with terminals  150 ,  155  over an internal network  140 . The tuner  230  further comprises at least one memory (hereinafter “memory”)  233  and at least one processor (hereinafter “processor”)  234  adapted to respond to requests from the terminals  150 ,  155 . 
         [0023]    Assume now that the terminals  150 ,  155  request services from the tuner  230  in the same order as that described hereinbefore, i.e. the first terminal  150  requests a first service after which the second terminal  155  requests a second service. The processor  234  preferably performs the functions of the media server  131  depicted in  FIG. 1 , and the latter is for that reason not shown. 
         [0024]    As already mentioned, if the two services are compatible, then the processor  234  will provide each terminal  150 ,  155  with the requested service. The present invention is used if the two services are incompatible. As previously remarked, the prior art tuner  130  has the choice between either stopping the first service to deliver the second service (without notifying the first terminal  150 ) or continuing the first service without delivering the second service (without notifying the second terminal  155 ). The inventive tuner  230 , however, overcomes this problem of the prior art in that the processor  234  either retrieves an image X from the memory  233  or creates an image Y (not shown), for example by superposition or insertion of relevant words on a white background, in order to send it to the relevant terminal. 
         [0025]    If, for example, the processor  234  is programmed to interrupt the first service to deliver the second service, then it sends the retrieved or created image to the first terminal  150  that then, in a sense believing it is part of the service, displays the image to the user. It is advantageous that the image in this case states something along the lines of: “The service has been interrupted to deliver a service to another terminal.” In case the network  100  comprises a plurality of terminals to which the delivered service is interrupted, it is advantageous to send the image to all these terminals. 
         [0026]    On the other hand, if the processor  234  is programmed to continue the first service and refuse the request for the second service, then it sends the retrieved or created image to the second terminal  155  that then, also in a sense believing that the service is delivered, displays the image to the user. In this case it is advantageous that the image in this case states words to the effect of: “The service cannot be delivered as a service is being delivered to another terminal.” 
         [0027]    As there is no need to access the access network  110  in order to retrieve an image and that the images may be made to consume very little bandwidth, the processor  234  is practically always able to send an image to a terminal. 
         [0028]    The skilled person will appreciate that the invention for example allows error messaging in a network without dedicated messages in the protocol used for communication. This is due to the fact that the message masquerades as content that is delivered to a terminal. 
         [0029]    The skilled person will also appreciate that the invention is not limited to images, but that other means of communication, such as sound, may also be employed, possibly in conjunction with images. 
         [0030]    It will be understood that the present invention has been described purely by way of example. Each feature disclosed in the description and (where appropriate) the claims and drawings may be provided independently or in any appropriate combination. Features described as being implemented in hardware may also be implemented in software, and vice versa. Connections may, where applicable, be implemented as wireless connections or wired, not necessarily direct or dedicated, connections. 
         [0031]    Reference numerals appearing in the claims are by way of illustration only and shall have no limiting effect on the scope of the claims.