Abstract:
The invention relates to a method and arrangement for storing and playing back TV programmes, in particular to an improved method and arrangement ( 100 ) for operating a network PVR ( 102 ). The inventive arrangement ( 100 ) for storing and playing back TV programmes comprises a PVR server ( 102 ) provided with means for receiving several digitally encoded TV channels, for feeding several terminals ( 104 ) and for recording storable TV programmes. The terminals ( 104 ) are provided with means for selecting storable TV programmes ( 106 ) and means for transmitting the choice to the PVR server. The inventive system also comprises means making it possible to playing back the TV programmes which are selected for storing by the terminal ( 104 ) in the form of a continuous TV programme on said terminal ( 104 ).

Description:
CLAIM FOR PRIORITY 
       [0001]    This application is a national stage application of PCT/EP2006/061076, filed Mar. 28, 2006, which claims the benefit of priority to U.S. Application Ser. No. 60/666,392, filed Mar. 30, 2005, the contents of which are hereby incorporated by reference. 
     
    
     TECHNICAL FIELD OF THE INVENTION 
       [0002]    The present invention relates to a method and an arrangement for the storage and playback of TV programs, and in particular, to a method and arrangement for operating a network PVR. 
       BACKGROUND OF THE INVENTION 
       [0003]    After decades of tape-based analog video recorders being the only means whereby home users could record and conveniently store programs screened on antenna, cable or satellite TV, with the availability of fast and at the same time inexpensive video processors and high-performance video codecs such as, say, MPEG2 (1994) and MPEG4 (1998) a number of mainly hard-disk-based digital machines providing not only straight video recording but also a number of convenience features have become available in recent years. 
         [0004]    The term personal video recorder (PVR), or sometimes digital video recorder (DVR), is frequently used for this new generation of devices. While these modern machines can of course be used like conventional VCRs for simple recording and subsequent playback of programs, they are capable of much more than that. For example, a frequently used feature of a PVR is what is referred to as time shifting, whereby the user can begin replaying a program even while it is still recording. Thanks to the high-performance hardware of a modern PVR, the picture quality achieved is superior to that of a conventional VHS or S-VHS tape machine. 
         [0005]    Time-shifted viewing also allows the user to “pause” a program initially being viewed live, e.g. to take a telephone call, and to resume playback later, it appearing to the user that he has actually paused the live screening and continued it later. In the background, however, pressing of the “Pause” button by the user has caused the user&#39;s PVR to record the current program, and pressing the “Pause” button again results, on the one hand, in the recorded program continuing to be recorded and, on the other, allows it to played back already. 
         [0006]    Another very popular feature of a PVR is the ability to skip lengthy sections in a recording with minimal delay. Often this is used during playback to skip blocks of commercials contained in the recorded program. A number of services have become established around this capability which facilitate locating the boundaries of the blocks of commercials, e.g. by storing the start and end of a block as points in time relative to the beginning of a program as a recording index, thereby enabling the commercials to be automatically skipped during playback. 
         [0007]    In addition to specially adapted entertainment electronics, multimedia PCs with suitable software are also increasingly being used as PVRs (known as home theater PCs, HTPCs). Technically there is virtually no difference between a specialized PVR and a PC PVR; both have a large (disk) memory, sufficient processor power and suitable video codecs. 
         [0008]    By means of configurable software or firmware, both platform variants are able to offer the user additional functions, such as program search, thematically geared to his favorite programs. The common feature of both platform variants is that recording takes place locally on the user&#39;s premises and the quantity of recordable programs is limited by the local disk memory. It is therefore often possible to transfer recorded programs from the device&#39;s internal memory to writable media such as re(writable) CDs or DVDs. However, this involves a time and a cost factor and, not least, the price of a PVR is also considerable. And even PVRs suffer from the problem that recording several programs simultaneously also requires a plurality of PVRs. More expensive multi-tuner machines solve this problem only to a limited extent, as there will always be fewer tuners than TV stations and, in addition, PVR hardware that is of sufficiently high performance for one channel reveals its limitations when required to record a plurality of channels simultaneously. 
         [0009]    To be able to offer users all the advantages of a PVR without them having to invest in a PVR, the white paper titled “Network PVR: Everything on Demand”, Jay Schiller, nCube Corporation, proposes a network PVR whereby storage, encoding logic and codecs are held available in the cable network by a provider. The user gets a unit with which he can select programs to be stored and can retrieve stored programs which are then transmitted to the user in real time by means of a broadband connection. Such a device can be much less powerful than a PVR or an HTPC. At the same time the user can rent virtually unlimited storage space on the PVR server, while the operator of the PVR server only needs to keep one copy of each program which is then distributed as required to those users who have stored that program in their (virtual) store. 
         [0010]    In one alternative, a network PVR of this kind can be designed so as to eliminate “programming” of the network PVR by the user, instead of which the user has access to all the shows in its program bouquet of, say, the last 4 weeks. 
         [0011]    In both cases, however, the user must decide separately for each program whether he would like to program it or to select from the pool of all recorded programs those programs of interest to him for playback. Where there is a great broadcaster offering, however, this is very laborious and time-consuming. 
       SUMMARY OF THE INVENTION 
       [0012]    The invention discloses a method and an arrangement for storing and playing back TV programs which make it easier for the user to play back interesting TV programs or other video content. 
         [0013]    In one embodiment of the invention, there is an arrangement for storing and playing back TV programs which includes a PVR server having a receiving device for receiving a plurality of digitally encoded TV channels, a supplying device for supplying a plurality of user terminals, and a recording device for recording TV programs to be stored, at least one user terminal having a selecting device for selecting TV programs to be stored and a transmitting device for transmitting the selection to the PVR server, and a playback device for playing back the recorded TV programs selected for storage by the user terminal as a continuous TV program on the user terminal. 
         [0014]    In another embodiment of the invention, there is a method for the storage and playback of TV programs, including, reception of a plurality of digitally encoded TV channels by a PVR server which supplies a plurality of user terminals and records TV programs to be stored, selection by a user terminal of TV programs to be stored and transmission of the selection to the PVR server, and playback of the recorded TV programs selected for storage by the user terminal as a continuous TV program on the user terminal. 
         [0015]    The selection of interesting TV programs is advantageously made easier for the user in that the user specifies a selection on his user terminal and can then play back the recorded programs as a continuous, personal TV program, the personal program then requiring no further user interaction in order to run. The selection can also include simultaneously broadcast programs which are then scheduled for playback in an order chosen by the user or by the PVR server. The user can of course skip programs or parts thereof during playback if these are of no interest to him in an individual case or generally. User preferences can be formed from the regular skipping of programs or parts thereof, for example such that only the first 30 minutes of a specific, regularly broadcast program are of interest to the user. 
         [0016]    The user can select the programs by using an electronic program guide (EPG). In this case a single selection can, for example, automatically schedule for recording all episodes of a series, all news programs of a specific channel or the program broadcast regularly at a specific time on one channel (e.g. the weekly changing film that is always broadcast in the same timeslot). 
         [0017]    The programs can also be selected by the user&#39;s specifying preferences, for example the mains news of all regional broadcasters; all films/series featuring a particular actor or having a particular director; and/or all reports, documentaries and/or films on a particular subject. The preferences can, as indicated above, be determined and/or updated at least partly automatically by analysis of which of the programs played back as a personal TV program are skipped by the user. A requirement for this is that for example the PVR server can determine, for each broadcast program, metadata permitting a synchronization with the user preferences from the videotext of the broadcasting stations or from the internet or by inputs by operating personnel of the PVR server. 
         [0018]    Finally, the selection of the programs can be made by a user group whose members know of one another, for example, that they have similar interests in terms of the choice of TV programs. One or more users within the user group can recommend a program for recording, and all the other users are then requested to approve this recommendation or reject it. If, for example, the majority of the votes cast is in favor of the recording, the program is recorded for all the users and subsequently played back within their personal TV program. It can also be provided in addition that personal preferences are managed for each user of the user group so that a program rejected by a user will not appear in that user&#39;s personal TV program and/or that a program desired by a user against the majority rejection will be included in that user&#39;s personal TV program. 
         [0019]    In a further embodiment it can be determined on the basis of further details which programs a user selects for his personal TV program and which he actually views. On the basis of the consumer behavior determined in this way, offerings from an on-demand video archive VoD (VoD=Video on Demand) can then be made selectively to the user; it is also possible to match the pricing structure thereto by, for example, offering films that are likely to be of particular interest to a user (e.g. the third part of a trilogy) at a higher price and films in which he has shown no interest to date (e.g. the first part of a different trilogy) at a lower price or free of charge. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0020]    Preferred exemplary embodiments of the present invention are explained in greater detail below with reference to a drawing. 
           [0021]      FIG. 1  shows an exemplary arrangement of a network or server and user terminals in accordance with the invention. 
       
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
       [0022]      FIG. 1  shows an arrangement  100  including a network PVR or PVR server  102  and user terminals  104 A . . .  104 N supplied by same. The PVR server  102  receives digitally encoded TV channels from an encoder  120 . The encoder in turn receives the TV channels from a receiver  122  which receives suitable TV signals via terrestrial antenna  124  and/or satellite antenna  126  and/or TV cable  128 . In this arrangement, the encoder  120  and the receiver  122  can be designed as a single unit. The encoder  120  uses a codec such as MPEG2 or MPEG4 or codecs derived therefrom to convert the TV signals initially present in analog form into an efficient digital data format. If a TV channel is already present as a digital data stream, e.g. as digital video broadcast DVB, (received terrestrially as DVB-T, via cable as DVB-C or via satellite as DVB-S), the encoder  120  can forward this data stream unmodified to the PVR server  102  or modify it prior to forwarding, e.g. by matching the bandwidth of the data stream to the bandwidth of the connection to the user terminals  104 . 
         [0023]    The PVR server  102  is linked to a mass storage device  108  such as a hard disk drive array or HDD array. Numerous methods of creating redundant hard disk mass storage arrays which can still deliver the stored data in full in the event of the failure of individual hard disks are well known in the technology. The use of such a redundant array, e.g. a redundant array of independent disks (RAID), is advantageous in relation to the present invention, since a PVR server  102  and the attached mass storage device  108  stores all or at least a large portion of the data of the TV recordings of a large number of users. 
         [0024]    The user terminals  104  are connected to the PVR server  102  via the TV cable network or via a DSL link, for example. Modern codecs permit an acceptable video quality and transmission rates of a few hundred kbit/s or more. With the bandwidths of several Mbit/s technically possible via DSL links, two or more parallel video streams (for different playback devices in the user&#39;s household) or a single high-quality video stream are conceivable. 
         [0025]    The user terminals  104  can be equipped with or linked to local memory  110  which is implemented for example as a conventional hard disk and/or as flash memory and/or as RAM. Special forms such as micro hard drives available in flash memory card format are of course also conceivable, flash memory having the advantage that data can be stored independently of the presence of a supply voltage while at the same time enabling particularly quiet user terminals  104  to be created, as flash memory has no rotating or other mechanical parts. 
         [0026]    In such an arrangement the memory  110  can be permanently connected to the user terminal  104  or be embodied as a replaceable medium. The memory  110  of the user terminals  104  is subject to less stringent requirements than the mass storage device  108  in terms of redundancy and failsafe operation. 
         [0027]    The user terminal or CPE  104  can be a set-top box which is connected to a video playback device  116 . Alternatively, the user terminal  104  can be integrated in the video playback device  116 . The video playback device  116  can be a conventional TV. Alternatively, it can be a monitor which does not have a TV tuner of its own. The user terminal  104  has a user interface  106  allowing the user for example to manage his archive of recorded TV programs. This user interface can, as is usual in the set-top box field, be implemented such that the user makes inputs via a remote control and outputs are displayed to him on the video playback device  116 . 
         [0028]    According to an exemplary embodiment of the present invention, the user interface  106  serves to display an EPG and enable the user to navigate therein. As already explained above, the EPG-based selection of programs can include not only individual programs but also, for example, all episodes of a series, all news broadcasts of a particular channel or even the program broadcast weekly or daily in the same timeslot. 
         [0029]    Alternatively, or in addition, it is possible to specify preferences by the user interface  106 , for example the main news of all regional broadcasters; all films/series featuring a particular actor or having a particular director; and/or all reports, documentaries and/or films on a particular subject. The preferences can be determined and/or updated at least partly automatically by analysis of which of the programs played back as a personal TV program are skipped by the user or which programs/program type he consistently programs in addition. A requirement for selecting programs on the basis of user preferences for recording by the PVR server  102  is that, for example, the PVR server can determine, for each broadcast program, metadata permitting a synchronization with the user preferences from the videotext of the broadcasting stations or from the internet or by inputs by operating personnel of the PVR server. 
         [0030]    In a further alternative, the operator of the PVR server offering users the option of setting up and managing user groups  140  (or this is done by the operator of the PVR server). For this purpose, a database  132  can be provided in which the user groups and the user terminals belonging to the respective user groups are recorded. The user groups are preferably set up and managed by the user interface  106 , for example by a user&#39;s “inviting” further users and the latter confirming the invitation. If a user is to be removed from the user group  140 , this can be effected for example by means of a majority decision of the other users—likewise supported by the user interface  106 . 
         [0031]    The members of such a user group  140  who know of one another, for example, that they have similar interests in terms of the choice of TV programs, select programs based on one of more users within the user group recommending a program for recording and all the other users then being requested to approve this recommendation or reject it. If, for example, the majority of the votes cast is in favor of the recording, the program is recorded for all users and subsequently played back within their personal TV program. 
         [0032]    Advantageously, a user who belongs to a user group that accurately reflects his own interests can rely exclusively on the selection of the other users for the choice of “his” personal program. With sufficiently large groups the user does not need to contribute actively to the selection for this purpose; depending on user group, his inactivity can be interpreted in the voting as abstention or approval. 
         [0033]    It can be provided in addition to manage personal preferences for each user of the user group  140  so that a program rejected by a user or always skipped during playback will not appear in that user&#39;s personal TV program and/or that a program desired by a user against the majority rejection will be included in that user&#39;s personal TV program. 
         [0034]    The inputs of a user or the users of a user group are sent to the PVR server  102  which generates data records identifying all the TV programs to be recorded from the data received (individual program, program groups, user preferences, votes of the users of a user group  140 ). The corresponding TV programs are earmarked for recording by means of a scheduler. A first database  130 , e.g. a user database, manages in this way the programs earmarked by a user for recording and checks the user&#39;s authorizations, e.g. whether the user has subscribed to the corresponding TV channel. 
         [0035]    When a TV program is transmitted, the PVR server  102  checks in conjunction with the database  130  whether a user (a single user suffices) has earmarked that program for recording. If this is the case, recording is performed, the data arising from the recording being able to be stored completely in the mass storage array  108  of the PVR server or subdivided into a local and a central part and stored accordingly in the memory  110  of the user terminal  104  or in the mass storage device  108 . If the program has been programmed for recording on a plurality of user terminals  104 , either a common copy can be provided, all or the central portion of which is stored in the mass storage array  108  of the PVR server  102 , or a separate copy is created for each user terminal. For each user terminal which had earmarked the program for recording, address information relating to the common or separate copy, e.g. a filename or other index information, is then stored in the first database  130 . A user-related entry of this kind can contain further information about the program in the form of metadata such as an expiration date or the positions of any blocks of commercials in order to enable same to be skipped. 
         [0036]    If the recording data is subdivided into central and local data, the local data is accordingly sent to the user terminals  104  on which the program is to be included in the personal TV program, the subdivision of the data being implementable in such a way that at least the central data stream, on its own, no longer supplies a decodable video signal (picture and sound). When the two volumes of data (from the memory  110  of the user terminal  104  and the mass storage device  108 ) are combined can the program be played back in its entirety. 
         [0037]    To initiate playback, a user accesses, via user interface  106  on the user terminal  104 , his personal TV program which is sent from the database  130  to the user terminal  104  for display on the screen  116 . In this case TV programs can also be viewed in real time, i.e. the PVR server  102  forwards the video data received from the encoder  120  to the user terminal(s)  104  whose personal TV program includes the corresponding program. A parallel storage of the video data can also be provided here in order to enable the users to “pause” the program. 
         [0038]    If the recording data has been subdivided into central and local data, the parts of the recording stored in the memory  110  of the selecting user terminal  104  and in the mass storage device  108  can be combined in the PVR server  102 . For this purpose, the data stored in the user terminal is first transmitted to the PVR server and combined there. The completed video data is then transmitted to the user terminal  104  for playback as a real-time data stream. 
         [0039]    Alternatively, the parts of the recording stored in the memory  110  of the selecting user terminal  104  and in the mass storage device  108  can be combined in real time in the user terminal  104 . In response to appropriate user input, by means of the PVR server  102  the incomplete video data is transmitted as a near-real-time data stream from the mass storage device  108  to the user terminal  104  where it is supplemented by the data stored in the user terminal  104  and played back. Near-real-time data stream, in this context, means that, depending on the selected subdivision of data between local memory  110  and mass storage device  108 , comparatively large volumes of data can also be present in the local memory, e.g. intro sequences which are played back first before the possibly hitherto buffered data from the mass storage array  108  is prepared for playback. 
         [0040]    In a further embodiment of the present invention, it can be determined which programs a user selects for his personal TV program, which he actually watches and how he otherwise uses “his” network-based PVR. On the basis of the consumer behavior determined in this way, Video on Demand offerings can then be made selectively to the user, which offerings can be delivered by a VoD server  150 ; it is also possible to match the pricing structure to the determined consumer behavior by, for example, offering films that are likely to be of particular interest to a user at a higher price and films in which he has previously not been interested at a lower price or free of charge. 
         [0041]    The following information can be evaluated for example automatically in order to determine consumer behavior:
       film genres, subject areas of reports and documentaries which are contained in a user&#39;s personal TV program or archive,   the preferences input by the user from case to case,   switchover, fast-forward and rewind actions by the user when viewing the recorded content, and/or   Video on Demand offerings consumed hitherto.       
 
         [0046]    Depending on currently applicable data protection regulations, it can be provided that the user first consents to the corresponding automated acquisition and use of personal data. 
         [0047]    It is obvious, and has also already been presented in detail for individual combinations, how the described exemplary embodiments of the present invention can be combined. 
         [0048]    It should be noted that the integration of the VoD server  150  in the arrangement  100  can be realized in different ways. For example, the PVR server  102  can, as shown in the figure, receive the video data from the VoD server  150  and forward it unchanged to the requesting user terminal  104 . Alternatively, the PVR server  102  can match the data rate to the data rate of the connection to the requesting user terminal  104 . It is also possible to link the VoD server to the user terminals  104  in such a way that the data does not have to pass through the PVR server (not shown). 
         [0049]    If the VoD server  150  is operated by a different operator from the PVR server  102 , it can be provided for data protection reasons that the consumer behavior of users who have consented to a corresponding use of their data only in respect of the operator of the PVR server  102 , is made accessible to the operator of the PVR server  102 . In this case the VoD server  150  can supply a list of content that is available for download on demand along with content-describing metadata to the PVR server  102 , which then presents a user with the content that fits that user&#39;s profile based on his consumer behavior and in response to the user selection then requests the content for the user in question from the VoD server  150 . 
         [0050]    If, on the other hand, the declaration of consent by the user also applies to the operator of the VoD server  150  (or if the operators of the PVR server  102  and the VoD server are identical), a user profile can also be sent to the VoD server  150  by the PVR server  102  or the database  130 , whereupon the VoD server  150 , bypassing the PVR server  102 , selects content for an offering and in response to a user request transmits requested content to the user.