Patent Application
20180146237
The invention relates to a method of controlling the rendering of an audio and/or video signal comprising trick play limited parts for which skipping during trick play is not desirable. The invention further relates to a time shift arrangement for program information representing an audio and/or video program comprising trick play limited program parts for which skipping during trick play is not desirable.
The revenue income of commercial TV-program providers is principally derived from commercials interspersed with the programming. As is well known, a TV show is typically interrupted by commercial breaks during which commercials are played. A program provider sells commercial time slots to advertisers for the purpose of placing commercials therein. The price of a commercial time slot varies with the anticipated size of the audience of the associated TV show, stemming from the assumption that the same audience would watch both the show and the commercial placed in such a time slot. That is, the more popular the show is, the more expensive the commercial time slots associated with the show.
Time shift services may adversely affect the return on their investment, inasmuch as the time shift service removes the traditional broadcast schedule constraint, and allows the user to view the program at a time with a delay. The fast-forward trick mode function afforded by the time shift service may negatively affect the advertising income. Using such a trick mode function, an user may fast-forward a TV program to skip commercials therein, thus rendering such commercials and advertisements ineffective. Advertisers are unlikely to pay well for ineffective commercials and advertisements.
The TV program providers are looking for solutions to reduce the possibilities for commercial skipping.
A method for counteracting skipping commercials is described in US2008193104.
US20060013557 discloses a personal video recorder. Trick mode control date is read from a computer file associated with a commercial and it is determined whether trick mode play is prohibited for the commercial. If trick play is not permitted for the commercial the prohibited trick play is disabled during play of the commercial.
Further US20080317433 discloses a playback apparatus for play back audio/video information stored as play items on a storage medium. A random access flag can be assigned to the play items. The value of the random access flag indicates whether jumps to entry points are allowed. If such jump is not allowed a request to a jump to such entry point results in a jump to the beginning of a clip audio/video clip stream pointed to by the play item.
It is an object of the invention to provide a method and arrangement which further counteracts the skipping of marked parts of broadcasted audio and/or video information.
According to a first aspect of the invention this is achieved by a method of controlling the rendering of an audio and/or video program comprising trick play limited parts for which skipping during trick play is not desirable.
whereby the audio and/or video program can be rendered in a live mode or time shifted mode, whereby in the live mode program information, representing the audio and or video program, is directly transferred to a rendering device, and whereby in the time shift mode the program information is transferred to the rendering device via a time shift buffer, the program information being stored in the time shift buffer and being read a time shift later than it is stored, and
whereby in a first trick play mode the time shift between the program information stored in the time shift buffer and the time shifted program information read from the time shift buffer is decreased, and whereby in a second trick play mode the time shift between the program information stored in the time shift buffer and the time shifted program information read from the time shift buffer is increased, and whereby in case that program information representing trick play restricted parts is read from the time shift buffer the first trick play mode is disabled, and
whereby in case the rendering is in the live mode the second trick play mode is disabled in case this would lead to read access to program information representing a program part which has not yet been rendered and which follows a trick play restricted part of the program part which has not yet been rendered.
According to a second aspect of the invention the object of the invention is achieved by a time shift arrangement for program information representing an audio and/or video program comprising trick play limited program parts for which skipping during trick play is not desirable, which arrangement comprises: an input for receiving the program information.
a transfer output to be coupled to a rendering device for rendering the program represented by the program information, a time shift buffer for storing the program information and outputting the stored program information a time shift later, and a controller which is operable in a first trick play mode in which the time shift between the program information stored in the time shift buffer and the time shifted program information read from the time shift buffer is decreased and a second trick play mode in which the time shift between the program information stored in the time shift buffer and the time shifted program information read from the time shift buffer is increased, whereby the arrangement is operable in a live mode in which the program information received on the input is transferred without delay to the transfer output and a time shifted mode in which the program information outputted by the time shift buffer is transferred to the transfer output, and whereby the controller is arranged to disable the first trick play mode in case the program information outputted from the time shift buffer represents trick play restricted parts and to disable between the program information stored in the time shift buffer and the time shifted program information read from the time shift buffer the second trick play mode in case this would result in that the time shift buffer outputs program information which represents a program part which has not yet been made available on the output and which is following a trick play restricted part program part which has also not yet been made available on the transfer output.
The invention is at least partly based on the insight that the parts with trick play restriction, such as for example commercials, can be skipped, by first switching the arrangement into the live mode and subsequently executing the second trick mode, such as for example a rewind mode, with which the read out of the shift buffer can be shifted to the end of the trick play limited part.
With the measures according to the invention this circumvention is not possible anymore, and TV program providers may continue to allow trick play to be used.
Further embodiments of the method and arrangement and the advantages thereof are presented hereinafter with reference to
The trick play restricted parts in the video program can be indicated in the metadata incorporated in the video information transferred.
In case of packetized digital video information the meta data can be incorporated in packets or parts of the packets which are reserved for this type of data.
It will be clear that the trick play limited parts can also be indicated in other ways than by meta data in the transferred video information. For example by means of software executing a dedicated algorithm or an application of a third party which for example available on the internet. The places of the trick play limited parts in the program can also be determined by using a data base in which the information about the places of the trick play limited parts are stored can be used. Further it is possible to mark a complete program as trick play limited in case the available methods for determining trick play limited parts give no results.
It is also possible to indicate parts for which no trick play limitations exist. Parts for which such indication, that there are no trick play limitations, is lacking can then be considered as trick play limited parts.
The invention will hereinafter be described with reference to equipment arranged for processing the video information representing the video part of a TV program. It will be clear that the invention is also applicable to equipment for processing audio information representing an audio program, e.g. radio program or an arrangement for processing both audio and video information.
The video information can be in analog format or digital format. An often used digital video format is the MPEG format, in which a sequence of images is coded according to one of the MPEG-standards for video information. However the invention is also applicable to video information coded according to other coding schemes or standards.
The arrangement 10 further comprises a time shift buffer 21 for temporarily storing the received video information before it is outputted. For time shifting, the stored video information is read from the time shift buffer 21 a shift time interval later than it is written into the time shift buffer 21. The reading speed is chosen equal to the writing speed so that the video information on an output 23 becomes available with a delay with respect the receipt of the video information on input 20 at a normal speed.
A read/write controller 22 controls the write and read process of the video information in the time shift buffer 21.
The time shift buffer 21 is preferably a so called circular buffer, in which the video signal is stored in memory locations with subsequent address locations within an address range. As soon as the location with the highest address in the address range is filled the writing continues with the lowest address in the address range. The position with the lowest address is hereinafter referred to as the begin BB of the time shift buffer 21. The read out is performed in a similar manner. Thus as soon the as the location with the highest address is read the read process continues with the lowest address. Read/write controller 22 uses a pointer WP to keep record of the actual write address and a pointer RP to keep record of the read location.
It will be clear to the person skilled in the art that also other buffers than circular buffers can be used. Each memory in which a constant time difference can be kept between the writing of the content and the reading of this content can be used.
The video information received on input 20 is supplied to an input 26 of a multiplexer 24 and the time shifted video information on output 23 is supplied to input 25 of the multiplexer 24. The multiplexer 24 is controlled by an arrangement controller 35.
The arrangement 10 is operable in a Live mode and Time shifted mode. In the Live mode the video information on input 26 is fed via multiplexer 24 to a transfer output 27 of the arrangement 10. In the time shifted mode the time shifted video information on the output 23 of the time shift buffer 21 is fed to the transfer output 27.
The transfer output 27 is coupled to an input 31 of the rendering unit 11. The rendering unit 11 is provided with a video processor 29 which is coupled with the input 31. The video processor 29 submits display driving signals to a video display 30 causing a rendering of the video program represented by the video information.
The arrangement 10 controller 35 is provided with a programmable processor for performing software programs stored in a program memory 28. These programs comprise software for controlling the read write controller 22 and the multiplexer 24 to cause trick play. The trick play can be operated in several modes such as Pause mode, Play mode, Fast Forward mode and Rewind Mode. In the Pause mode the read out of the time shifted buffer 21 is stopped and video processor 29 is brought under control of controller 25 in a mode wherein it submits in an usual manner driving signals to the display 30 which cause a rendering of a still picture corresponding with latest picture available in video information on transfer output 27.
In the Play mode the video information in the time shift buffer 21 is read out at the time shift later than it was stored in the time shift buffer 21, whereby the read speed is equal to the write speed. The video information read from the time shift buffer is submitted to the video processor via the transfer output 27 which is brought by controller 25 in a mode where it submits driver signals which cause the rendering of the video program represented by the video information received on input 31 at normal speed. This results in a time shifted rendering of the video program on the display 30.
In the Fast Forward mode the read out of the time shift buffer a sequence of forward jumps are made, each time skipping a part of the video information. This results in that the video information is rendered on the display with higher speed than normal playback. Usually Fast Forward can be performed at different speeds, but always with a speed that is higher than the normal playback speed.
In the Rewind mode the video information is read out in reversed order resulting in that the video program is rendered in reversed order. Usually the Rewind mode can be performed with different speeds. In principle the speed in the Rewind mode can be any speed. In other words the Rewind speed can be higher, equal or lower than the normal playback speed. The trick play processes are initiated under control of trick play commands, which can be for example user commands which can be given by a user via an user interface 32 comprising user command buttons 33, for example one separate button 33 for each of the different modes. The user commands are received by the arrangement controller 35 via a usual communication channel for example a signal bus 34.
The memory 28 further comprises software for storing control data related to the contents stored in the time shift buffer 21. These control data comprises the pointer BB to the beginning of the time shift buffer 21. If a new storing cycle of storing video information is started, for example after a change of a video channel or after switching on the arrangement, the storing starts at the address indicated by this pointer BB.
The control data also comprises the pointer WP which points to the actual address in which the data received on the input of the time shift buffer 21 is stored and a pointer RP which points to the actual address of the read out of the time shift buffer.
The control data also comprises the address ranges of the video information in the time shift buffer 21 which is already read, and consequently rendered on the display 30. The control data also comprises the address ranges of the locations in the time shift buffer where trick play restricted parts stored. These address ranges are for example determined during the writing of the trick play restricted parts.
Finally the control data comprises the address ranges of the video information parts representing the program parts with the trick play restrictions. These ranges can be derived from the meta data in the video information.
The trick play processes executed in the different trick play modes and Live mode are described hereinafter with reference to
If so, then step S3 is performed, in which the read pointer RP is set to a value that points to the part of the video information stored in the time shift buffer just before the Pause mode was initiated. This value of the read pointer is maintained until it has to be changed for another trick play process.
Subsequently step S4 is performed in which the Live mode is ended. Step S4 is followed by step S5 in which a pause play is executed.
If in the execution of S2 it is determined that the arrangement was not operating in the live mode, then all trick play processes are stopped in step S6, followed by the execution of the pause play process in step S5.
However, if it appears in step S11 that the arrangement was not operating in the Live mode, then all trick mode processes are stopped in S13 and subsequently step S14 is executed. In Step S14 the read out speed of the time shift buffer is set at a value corresponding with the speed with which the video information is written in the time shift buffer 21. The read pointer RP maintains the value which it had at the end of the previous trick play mode. After the execution of S14 the video signal is fed to the output 27 in a time shifted manner.
If during the execution of step S31 it is determined that the arrangement was operating in the Live mode, then in step S36 it is determined on the basis of the control data whether the Rewind mode is allowed. The Rewind is only allowed in case the Rewind mode will not result in that the time shift buffer outputs program information which represents a program part which has not yet been made available on the output and which is following a trick play restricted part program part which has also not yet been made available on the transfer output 27. This is the case when video information representing trick play restricted parts which are not yet outputted to the transfer output 27 are present in the time shift buffer between the begin of the time shift buffer and the actual writing s15 position. The test in step S36 is made on the basis of the address ranges included in the control data.
If in step S36 it is determined that the rewind mode is not allowed, then in step S37 a jump to a subprogram SP for disabling the Rewind mode is made.
The subprogram starts with the execution of step S40. In this step it is determined whether the position in the time shift buffer, indicated by the registered reading pointer RP, is between the actual writing position and the position of the oldest program information the time shift buffer 21. If so, a jump to this position is made in step S41 and the arrangement is brought in the Play mode in step S42, resulting in the output of a still picture stored at the position indicated by RP, which is the position where the read out in the previous trick mode stopped.
If in step S40 it is determined that the pointer RP points to an address before the location with the oldest stored program information, then in step S43 a jump to the location where this oldest program information is stored is made. After the step S43 the Pause mode is entered in step S42, resulting in an output of a still picture of the oldest program part represented by the program information stored in the time shift buffer 21.
If it appeared during the execution of Step S75 that a video part with trick play restrictions has been reached, then it is checked in step S78 whether this video information has already been read from the time shift buffer to be rendered. This checking continues until video information is reached which has not yet been read. If such unread video has been reached it is checked in step S79 whether the information currently has still trick play restrictions. If so this means that a part of the information has been reached which is not yet read and rendered. Skipping this part is not allowed. The trick play is stopped and the Live mode is entered in step S77. Alternatively, the Play mode could be entered instead of the Live mode. If no trick play restrictions are detected in step S79, then the process is continued with step S75.
The effect on the trick play of the control processes of
As soon as this maximum length has been reached the oldest information in the time shift buffer is overwritten with the latest received video information. The stored contents are divided in 3 parts. Parts indicated by reference signs 73 and 74 comprise video information having no trick play restrictions. A part 75 indicates video information with trick play restrictions.
Location 76 indicates a read position for a situation wherein the arrangement 10 is in Play mode. The part between position 72 and 76 is already read from the time shift buffer and rendered on the display 30. The length of this part is indicated by Lp.
Reference sign 77 indicates an empty part of the time shift buffer 21 in which no video information of the current program is written yet.
Starting from position 76 several trick play modes are possible. In the Rewind mode the part between the position 76 and 72 can be read out in reverse order so as to cause a rendering of the video in reversed order. The flow chart of the process controlling the Rewind mode is described hereinbefore with reference to
In this process in step S34 it is checked whether the begin 72 has been reached. And if, so the Play mode is entered.
Starting from position 76 the Fast Forward mode is also possible. In case the Fast Forward mode is entered the video contents is read in forward order skipping parts of the video information so as to cause a rendering at high speed. The flow chart of the process controlling the Fast Forward mode is described hereinbefore with reference to
After the live position has been reached the Rewind mode to move the read out position in the direction of position 78 is disabled by the execution of step S36 in the process shown in
In this way it is prevented that a user can skip the video information part 75 by jumping to live rendering followed by a Rewind to the beginning of part 74.
If a Rewind command is given this will result in a Jump to location with was read at the moment that the arrangement was set into the Live mode, as described hereinbefore with reference to
For the interval Lp all trick modes are allowed. Although the part between location 78 and reading position 80 represents a video program part with trick play restriction trick play modes for this part is allowed because this information is already been read and the program parts represented by this information has been rendered. So these program parts are already presented to the user. However the Fast Forward mode is not allowed from reading location 80.
A Fast Forward command will result in a switch to the Live mode in step S78 and S79 as described with reference to
Since in this situation all video information parts representing video programs with trick play restricted are already played and rendered, all trick play modes are allowed for the video information stored in the interval L.
In embodiments of the method and arrangement according to invention in which program information representing a plurality of audio and/or video programs is stored in the time shift buffer it may occur that the user wants to watch an entire program, starting from the beginning of the program. However this program may be stored in the time shift buffer after a program with one or more trick play restricted part. If so then with embodiments described hereinbefore the user is obliged to first watch the trick play limited part of the program stored before the desired program before the desired program can be watched. To prevent this annoying situation, the controller 35 can be arranged to jump over program information representing trick play limited parts to program information representing the begin of a program independent from the information which precedes the said program information in the time shift buffer.
The TV apparatus 50 comprises a receiver 54 for receiving user commands from a remote control device 55 which is provided with user interface 32.
By means of a remote controller 55 a user can send trick play request commands to the TV apparatus 50. A remote control signal receiver 54 is coupled to signal bus 34 for forwarding the trick play request commands to arrangement 10. In the TV apparatus described with reference to
Broadcast TV signals are often submitted by a network provider to their clients, using a network, for example a cable network or the internet. A server or head end is coupled to the network to submit a plurality of channels to the network. The clients are also coupled to the network channels to receive the channels submitted by the server or head end. Recently network providers started offering services whereby a time shifting buffer for a client is incorporated on the head end side or server side. For each client who wants to make use of such time shift service a time shift buffer is present.
A internet receiver unit 62 is also coupled to the internet 61.
The server comprises a content unit 64 in which video information is stored which has to be sent to the receiver unit 62. The video information is submitted via the arrangement 10 to a streaming unit 63 which creates a video stream which is sent via the internet to receiver unit 62. The video information received by the receiver unit 62 is submitted a display device 66, e.g. a monitor or TV-apparatus, for rendering the video information. The server 60 comprises a communication unit 65 coupled to the internet 61 to receive user commands from receiver unit 62 at the client side. The communication unit forwards the user commands to bus 29 of arrangement 10.
By entering the user commands on the receiver side the arrangement 10 can be brought in the Live mode in which the video information stored in content unit 64 is fed to the output 27 without a delay so that a video stream representing the live video information is streamed to the receiver unit 62.
The arrangement 10 can also be brought in the trick play modes by means of the user commands as described with reference to
Alternatively, a pointer or indicator can be dragged (continuous press and move) over a representation of the buffer/part of the buffer, selecting another playback point, or a pointer may be placed (one time click on the new position) to another position in a representation of the buffer I/part of the buffer. All these trick play modes have in common that the time shifts are decreased as a result of operating the arrangement in these trick play modes.
In the embodiments of the method and arrangement according to the invention described hereinafter the Rewind mode is the second trick play mode that cause a decrease of the time shift. It is to be noted that the invention is not limited to embodiments in which the second trick mode is the Rewind mode. The invention is also applicable for all embodiments in which the increase of the time shift is caused by other trick play modes, for example the scrubbing mode or a mode wherein a pointer is dragged or placed to a new location.
Although several embodiments of the present invention have been illustrated in the accompanying drawings and described in the above detailed description, it will be understood that the invention is not limited to the embodiments disclosed, but is capable of numerous modifications without departing from the scope of the invention as set out in the following claims.
| Number | Date | Country | Kind |
|---|---|---|---|
| 14179774.6 | Aug 2014 | EP | regional |
| Filing Document | Filing Date | Country | Kind |
|---|---|---|---|
| PCT/EP2015/067862 | 8/3/2015 | WO | 00 |
