AU2008200302B2

AU2008200302B2 - System for resolving tuner conflict

Info

Publication number: AU2008200302B2
Application number: AU2008200302A
Authority: AU
Inventors: Peter Samuel Vogel
Original assignee: VOGEL ROSS Pty Ltd
Current assignee: VOGEL ROSS Pty Ltd
Priority date: 2007-01-22
Filing date: 2008-01-22
Publication date: 2013-09-05
Anticipated expiration: 2028-01-22
Also published as: AU2008200302A1

Abstract

An improved DVR can record programs received in part from a local tuner and in part from another source such as the Internet. This ensures that parts of recordings are not missed due to schedule inaccuracies or tuner conflicts. 5 Programs are normally recorded off-air using the local tuners. If a problem results in a section of a recording being missed, a request is sent to a central office to connect the DVR to a video stream from a suitable tuner at the office via a network such as the Internet. By recording the majority of the desired program locally within the DVR, utilisation of network bandwidth is minimal 10 and the invention can be used even in situations where the Internet bandwidth is insufficient for realtime streaming. Antenna. 1 ................ Tuner2 Caches Tuner3 Cache6 Server S Tuner4 Cache 7 Antenra 10 Antenna 11 Internet 9 Antenna 12 -DVR 15 Fig. 1

Description

SYSTEM FOR RESOLVING TUNER CONFLICT 5 FIELD OF THE INVENTION The present invention relates to digital video recorders (DVRs) and in particular methods of preventing loss of parts of recordings due to mismatch between the time at which the recording has been scheduled and the time the 10 program is actually aired. The invention also assists in recording multiple programs that air simultaneously. BACKGROUND OF THE INVENTION 15 When recording TV shows off-air, parts of the recording might be missed, for example because a show runs overtime and the tuner is required for recording a subsequent show. This has been partly addressed by inclusion of a second tuner in some DVRs 20 however this still often fails, for example if a show runs overtime and no padding (extra recording time) has been allocated, or if a spare tuner is not available. One system that has been proposed to address this problem is to record 25 broadcasts at a central office and allow householders to access these recordings by means of a suitable set-top-box. This system, sometimes referred to as a "network DVR", has the advantage that the set-top-box does not need to have tuners or disk storage for programs. However such systems require a communications network capable of streaming programs to multiple 30 customers in real time. Recording programs at a central office may also not be permitted for copyright reasons, some jurisdictions restricting recording of TV programs to domestic premises.

SUMMARY OF THE INVENTION It is an object of this invention to provide a system and process for recording programs or parts of programs that would otherwise be missed by utilising 5 spare tuners located remotely at a central office and accessed via the Internet. The customer's DVR is connected to the Internet and equipped with at least one local tuner. Programs are normally recorded off-air using the local tuners. 10 If a problem results in a section of a recording being missed, a request is sent to a central office to connect the DVR to a video stream from a suitable tuner at the office via a network such as the Internet. By recording the majority of the desired program locally within the DVR, utilisation of network bandwidth is minimal and the invention can be used even in situations where the Internet 15 bandwidth is insufficient for realtime streaming. In one aspect, the present invention provides a method of recording broadcasts comprising the steps of receiving a desired broadcast program; recording said program to a local storage device; and, if the desired program 20 was not recorded in its entirety; requesting from a remote server the portions of said desired program which were missing from the recording; and receiving said missing portions. In another aspect, the present invention further includes the step of merging 25 said missing portions with the incomplete recording. In another aspect, the invention further includes the steps of calculating whether a desired broadcast has been correctly recorded by referring to correction data describing the actual time at which said broadcast started and 30 finished and comparing this to the time at which the recording started and finished. This correction data can be provided, for example, by persons monitoring the broadcasts at a central office, by the home viewer's personal observation, or by signaling provided electronically, such as signals embedded within the broadcast. 2 In yet another aspect, the present invention further includes the step of receiving a plurality of broadcasts at a central office; caching said received broadcasts; and transmitting said cached broadcasts to said remote server. 5 The invention also consists in digital video recorder means adapted to receive a desired broadcast program using a local tuner; record said program to a local storage device; and, if the desired program was not recorded in its entirety; request from a remote server the portions of said desired program 10 which were missing from the recording; and receive said missing portions. The invention also consists in digital video recorder means adapted to indicate to a user if a requested recording has not been completed in its entirety. For example, the invention can be arranged to interrogate a remote server after 15 each recording is completed to obtain actual start and end times of the program theoretically completely recorded, compare the actual times to the time period recorded, and if part of the recording was missed notify the user accordingly, for example by a pop-up message or by adding a warning to the filename or file information. 20 In another aspect, said digital video recorder means is further adapted to merge said missing portions with the incomplete recordings. In some embodiments of the invention the missing portions of recordings are 25 merged with the incompletely-recorded file to form a new, complete file. In other embodiments the incomplete recording is not corrected, the missing portions being played to the viewer at the appropriate time to give the impression of a complete recording. 30 Whereas in some embodiments the invention is applied to timeshifted television viewing, it can also be applied to viewing in realtime. For example, in one embodiment the invention comprises a television receiver and display device equipped with a tuner and a network interface. When the viewer chooses to watch a particular program, if that program is available through the 3 tuner, the tuner is routed to the display, but if the program is not available through the tuner, the network interface is utilised to fetch the desired program from a remote server. Availability of the program through the tuner may be dependant on whether the program is being broadcast at the desired time of 5 viewing, or the tuner might me required for another task such as recording. The source of program being viewed can also switch between alternative sources several times during viewing of a given program. DESCRIPTION OF A PREFERRED EMBODIMENT 10 An embodiment of the invention will now be described with reference to the block diagram Fig. 1. Referring now to Fig. 1, Antenna 1, Tuners 2-4, caches 5-7 and server 8 are 15 located at a central office. In this example three tuners are used, however in practice it is preferable that the number of tuners be sufficient to receive all the popular channels available to the users of the invention. Caches 5-7 are continuously buffering the program received by each tuner and are preferably large enough to cache many hours or even days of program. 20 Fig I also shows three DVRs (13-15) which represent the DVRs installed at viewers' homes. In practice there are of course many thousands of these. Each DVR receives programs through its local antenna (10-12) and is also connected to the Internet 9. 25 In addition to the personal video recorder software usually supplied with such devices, the DVRs incorporate additional software to implement the novel features of the present invention. Operation of the software and overall system will now be described by way of certain examples. 30 In a first example, the user of DVR 14 desires to record a show on channel 9 from 7.30pm to 8.30pm, then- a show on channel 10 from 8.30pm to 9.30pm. The DVR has a single tuner. Following the traditional protocol, at 7.30pm DVR 14 tunes to channel 9 and starts recording signals received through 4 Antenna 11. At 8.30pm it stops recording channel 9, closes the recorded file, tunes to channel 10, and starts recording a new file. However in this example the show on channel 9 is running 5 minutes overtime, so the last 5 minutes of the show are missing from the recording. 5 After starting the new recording, DVR 14 runs a software routine which queries server 8 at the central office to determine the actual end time of the channel 9 show it has just recorded. In this example, server 8 replies with a message indicating that the show of interest is not yet finished. DVR 14 then 10 checks its stored recording of the channel 9 show to determine the time of the end of the recording, and sends a request to server 8 to deliver the channel 9 cached program starting from that time (the time at which the recorded file ends). Server 8 accordingly accesses data from the appropriate point in the cache assigned to channel 9 and starts delivering the program at whatever 15 speed the network and servers will allow. DVR14 receives this data and appends it to the relevant recorded file. When the end of the cached program is reached delivery is terminated. In many cases the DVR has multiple tuners, however conflicts can still arise 20 when recording shows which overlap. For example if two tuners are provided and two programs are scheduled to record, one tuner may be occupied recording a previous show which is running overtime. In this case too the invention allows the DVR to use a spare tuner at the remote office to cover the local tuner shortfall. 25 In another example, the invention is helpful in the situation where a viewer decides to record a program after the broadcast has started. This is a common requirement and is handled to some degree by DVRs which provide an internal buffer memory which is continuously being recycled so that when 30 the user decides to record a show that has already started, there is a good chance that the beginning of the show is in the buffer and that buffer is prepended to the recording file. This however assumes that the DVR has been tuned to the channel of interest since the desired show started, otherwise the buffer memory will not contain the desired show. 5 Using the present invention in this exemplary case, when the viewer hits "record" after watching the first 5 minutes of a show, the local DVR starts recording off-air and the first 5 minutes of the show are fetched from the 5 remote office and prepended to the recorded file. It will be understood that the foregoing describes only some embodiments of the invention, and many variations are possible without departing from the scope of the inventive concept. 10 For example, although the invention is applicable to DVRs using no local tuners, it is preferable that the DVR have at least one local tuner as this reduces the amount of data that must be communicated over the Internet. 15 Whereas the invention is described as utilising tuners to capture broadcasts at the remote office, this is by way of example only and the invention can also be practised using other means of sourcing content at the remote office. For example the tuners 2-4 of Fig 1 could be replaced, network interfaces or tape players or any other means of receiving the content to be served. 20 It is also anticipated that methods other than the Internet can be used for communicating programs between the remote tuners and the DVR. For example the programs can be transmitted over a wireless data service, digital data channel of a television broadcast, or any other communications medium. 25 Similarly, whereas the invention is described as utilising broadcast signals received through antennas, the invention can also be beneficially applied to program received by any other medium, for example cable or digital network. Furthermore the remote spare tuners need not be located in a central office. 30 For example they may be located remotely from the DVR but within the same building. One such application is in multiple dwelling units, where individual occupants have their own DVRs with say one tuner, supplemented by a pool of spare tuners located centrally in the building and accessed by multiple DVRs within the building via a network. 6 The network may for example be an Ethernet network connected by cable or wirelessly. Other networks such as Ethernet-over-coax, Ethernet-over-mains, Ethernet-over-phone can also be beneficially utilised. 5 It is also understood that multiple central offices might be used in implementing the invention. This can offer greater capacity to service large numbers of customers or increase the number of channels available to be cached, including services broadcast in different geographical areas. One 10 further benefit of including extra geographical coverage might be to capture programming in a different timezone so that if, for example, a user requires part or all of a program that is no longer in the cache of their nearest central office, the same program might be aired later in a different timezone and could accordingly be captured at that time. 15 In some extensions of the invention the recording devices can alert the appropriate central office that it will require a program to be recorded Whereas the invention is described in relation to television broadcasts, this is 20 by way of example only and it should be understood that the invention can be equally well applied to radio, textual information, websites or any other information or mix of different types of information, and as well as being applied to broadcasts the invention can also be applied to narrowcasts, subscription services or any other information conveyance system. 25 Furthermore, whereas the examples herein describe the operation of the invention as recording the desired program first, in part, from the local tuner and then subsequently filling in the missing content from a remote server, the invention can also operate in a different order, that is portions of the program 30 can be fetched from the remote server before, during or after recording parts of the program from the tuner. 7

Claims

1. A video recording system comprising: a central office comprising at least one television signal tuner; 5 a video recorder comprising at least one local television signal tuner and located remotely from said central office; and means for communicating television signals from a tuner at said central office to said remotely located video recorder; wherein said video recorder is adapted to make a television program recording 10 using television signals communicated from said central office merged with signals from said local television signal tuner.

2. A video recording system according to claim 1 wherein said central office also comprises means to store and retrieve programs received by said television signal tuner. 5

3. A video recording system according to claim 2 wherein the television program recording is made by: recording signals from said local television signal tuner; testing whether the recording made was a complete recording of a program; and 20 if the recording was not complete, completing it using television signals communicated from said central office.

4. A video recording system according to claim 1 wherein the television program recording is made by recording signals from said local television signal tuner when said signal is available and at other times by recording signals 25 communicated from said central office.

5. A video recording system according to claim 3 wherein the test of whether the recording was complete is based on information provided by persons monitoring the program at a central office. 3

6. A video recording system according to claim 3 wherein the test of whether the recording was complete is based on electronic information signaling provided in conjunction with the received program.

7. A video recording system according to claim 3 wherein the test of whether the 5 recording was complete is based on electronic information signaling received from a remote server.

8. A video recording system according to claim 3 wherein the test of whether the recording was complete is based on at least scheduled broadcast times of programs recorded. [0

9. A video recording system according to claim 2 wherein said means to store and retrieve programs is adapted to store at least part of a television program in response to a request from said remote video recorder.

10.A video recording system according to claim 1-8 and further adapted to indicate to a user if a requested recording has not been completed in its 5 entirety.

11. A video recording system comprising: a central office comprising at least one television signal tuner; a video recorder comprising at least one local television signal tuner and located remotely from said central office; and 0 means for communicating television signals from a tuner at said central office to said remotely located video recorder; wherein said video recorder is adapted to output to a viewing device a video signal representing a first television programs communicated from said central office while recording a second television program. 25 4