WO2011077057A1 - Method and device for video recording and broadcasting by so-called time shifting - Google Patents

Method and device for video recording and broadcasting by so-called time shifting Download PDF

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Publication number
WO2011077057A1
WO2011077057A1 PCT/FR2010/052890 FR2010052890W WO2011077057A1 WO 2011077057 A1 WO2011077057 A1 WO 2011077057A1 FR 2010052890 W FR2010052890 W FR 2010052890W WO 2011077057 A1 WO2011077057 A1 WO 2011077057A1
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WIPO (PCT)
Prior art keywords
recording
broadcasting
transmission channel
broadcast
rate
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PCT/FR2010/052890
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French (fr)
Inventor
Daniel Creusot
Original Assignee
Softathome
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Publication date
Application filed by Softathome filed Critical Softathome
Priority to EP10808924A priority Critical patent/EP2517465A1/en
Publication of WO2011077057A1 publication Critical patent/WO2011077057A1/en

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Classifications

    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04N—PICTORIAL COMMUNICATION, e.g. TELEVISION
    • H04N5/00—Details of television systems
    • H04N5/76—Television signal recording
    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04N—PICTORIAL COMMUNICATION, e.g. TELEVISION
    • H04N21/00—Selective content distribution, e.g. interactive television or video on demand [VOD]
    • H04N21/40—Client devices specifically adapted for the reception of or interaction with content, e.g. set-top-box [STB]; Operations thereof
    • H04N21/41—Structure of client; Structure of client peripherals
    • H04N21/414—Specialised client platforms, e.g. receiver in car or embedded in a mobile appliance
    • H04N21/4147—PVR [Personal Video Recorder]
    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04N—PICTORIAL COMMUNICATION, e.g. TELEVISION
    • H04N21/00—Selective content distribution, e.g. interactive television or video on demand [VOD]
    • H04N21/40—Client devices specifically adapted for the reception of or interaction with content, e.g. set-top-box [STB]; Operations thereof
    • H04N21/41—Structure of client; Structure of client peripherals
    • H04N21/426—Internal components of the client ; Characteristics thereof
    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04N—PICTORIAL COMMUNICATION, e.g. TELEVISION
    • H04N21/00—Selective content distribution, e.g. interactive television or video on demand [VOD]
    • H04N21/40—Client devices specifically adapted for the reception of or interaction with content, e.g. set-top-box [STB]; Operations thereof
    • H04N21/43—Processing of content or additional data, e.g. demultiplexing additional data from a digital video stream; Elementary client operations, e.g. monitoring of home network or synchronising decoder's clock; Client middleware
    • H04N21/432—Content retrieval operation from a local storage medium, e.g. hard-disk
    • H04N21/4325—Content retrieval operation from a local storage medium, e.g. hard-disk by playing back content from the storage medium
    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04N—PICTORIAL COMMUNICATION, e.g. TELEVISION
    • H04N21/00—Selective content distribution, e.g. interactive television or video on demand [VOD]
    • H04N21/40—Client devices specifically adapted for the reception of or interaction with content, e.g. set-top-box [STB]; Operations thereof
    • H04N21/43—Processing of content or additional data, e.g. demultiplexing additional data from a digital video stream; Elementary client operations, e.g. monitoring of home network or synchronising decoder's clock; Client middleware
    • H04N21/433—Content storage operation, e.g. storage operation in response to a pause request, caching operations
    • H04N21/4333—Processing operations in response to a pause request
    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04N—PICTORIAL COMMUNICATION, e.g. TELEVISION
    • H04N21/00—Selective content distribution, e.g. interactive television or video on demand [VOD]
    • H04N21/40—Client devices specifically adapted for the reception of or interaction with content, e.g. set-top-box [STB]; Operations thereof
    • H04N21/43—Processing of content or additional data, e.g. demultiplexing additional data from a digital video stream; Elementary client operations, e.g. monitoring of home network or synchronising decoder's clock; Client middleware
    • H04N21/44—Processing of video elementary streams, e.g. splicing a video clip retrieved from local storage with an incoming video stream, rendering scenes according to MPEG-4 scene graphs
    • H04N21/4402—Processing of video elementary streams, e.g. splicing a video clip retrieved from local storage with an incoming video stream, rendering scenes according to MPEG-4 scene graphs involving reformatting operations of video signals for household redistribution, storage or real-time display
    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04N—PICTORIAL COMMUNICATION, e.g. TELEVISION
    • H04N5/00—Details of television systems
    • H04N5/76—Television signal recording
    • H04N5/907—Television signal recording using static stores, e.g. storage tubes or semiconductor memories

Definitions

  • the present invention relates to a method and a device for recording and broadcasting a TV transmission channel according to the principle known as "timeshifting".
  • timeshifting comes from the English expression “time shifting”, a time shift in French, and allows a real-time recording of a television program while allowing its viewing slightly delayed compared to its real-time broadcast.
  • the recording length is always limited for example to two hours or less.
  • the functionality of "TimeShifting” is realized by recording on a memory that is used as a circular buffer. For example, depending on the expected duration of the "TimeShifting" (maximum time between pause and recovery without loss of data), the size of the circular buffer can reach 8 GB (8Mbits / s for 2 hours).
  • the "timeshifting" feature first appeared in living room recorders or PVR (for "Personal Video Recorder") incorporating a high-capacity hard disk (HDD) for store the contents of the circular buffer.
  • the present invention finds a particularly interesting application in Flash NAND technology which offers a large memory capacity for a reasonable cost.
  • This type of memory occupies little space and consumes less energy than hard disks in particular.
  • a flash memory is a nonvolatile semiconductor mass memory that is easily accessible for writing and reading. It keeps the information contained therein even when it is no longer electrically powered.
  • such technology does not allow permanent recording functionality as in hard drives. This is why we introduced the notion of "timeshiftOnly" for a "timeshifting" feature based on flash memory.
  • NAND flash memory has a mean duration between two MTBF faults (for "Mean Time Between Failures") relatively low, this limits the number of write cycles / erasure to a few hundred thousand while hard drives offer several million.
  • the present invention is of a broader scope since it can be applied to any type of memory used as a "buffer", such as hard disk or NOR flash memory.
  • An object of the present invention is to overcome the aforementioned drawbacks by proposing a method of "timeshifting" optimizing the write / read cycles.
  • the above purpose is achieved with a method for recording and broadcasting a TV transmission channel according to the so-called timeshifting principle, wherein:
  • the TV transmission channel is recorded in real time on a memory medium
  • the said TV transmission channel is delayed.
  • the TV transmission channel is broadcast at a broadcasting speed which is higher than the recording speed; this diffusion rate being determined automatically.
  • the memory medium is used as a buffer or "buffer” so that the program being recorded can be viewed with a time offset.
  • a TV transmission channel is an audio / video signal relating to a television channel.
  • the reading is performed faster than the writing in the memory so that the delayed reading catches the broadcast in real time.
  • the diffusion rate may be 1 to 10 percent higher, but it is preferably 1 to 2 percent higher than the recording rate. With such a range, the user distinguishes little or not the acceleration of the reading.
  • This diffusion rate may be predetermined at a fixed value or determined according to the duration of the TV transmission channel already recorded in the memory medium.
  • the program duration already recorded is detected, then the diffusion rate is determined which would make it possible to catch the reading as quickly as possible in real time while respecting criteria of quality or perceived by the user.
  • the memory medium is a NAND flash memory which is notably used as a circular buffer where writing or recording causes the erasure of data that are too old.
  • the recording and broadcasting is stopped in response to a standby instruction of this display screen.
  • This is again an implementation mode to preserve the lifetime of the memory by avoiding any unnecessary write / read cycle.
  • It is also planned to launch the "timeshifting" process according to the invention only in response to a user instruction, for example by pressing the "pause” button on its remote control.
  • It is also planned to stop recording or writing in the memory after a predetermined time during which the user has not transmitted another instruction. This protects against all forgetting by the user in a permanent recording mode.
  • a device for receiving and broadcasting to a TV channel television transmission according to the so-called principle of "timeshifting" comprising a memory medium for recording in real time a TV transmission channel, and for broadcasting, during recording, said TV transmission channel.
  • this device comprises a processor configured to automatically determine a broadcast rate that is greater than the recording rate, and to broadcast the TV transmission channel to the television at this broadcast rate.
  • Configured processor means the presence of a software program allowing the processor to perform operations.
  • connection between the device and the television is preferably a bidirectional link such as for example an HDMI bus.
  • Figure 1 is a general view of a Set Top Box connected to a television
  • Figure 2 is a general view of a video channel processing chain according to the invention.
  • the circular buffer or “buffer” consists of a NAND flash component as shown at 4 in FIG. 2.
  • This component may be another technology such as a hard disk, NOR flash memory, or other.
  • the method according to the invention is implemented in the processing chain shown in FIG. 2 in order to preserve the MTBF of the NAND flash memory 4 which has a relatively small number of write / erase cycles.
  • This processing chain of Figure 2 is managed by a CPU processor that is configured to execute system instructions or software codes.
  • the tuner of the processing chain is powered by a video transmission SRCl TV source connected for example to a radio antenna in the case of reception of digital terrestrial television channels.
  • the tuner is used to select the frequency of the modulated "transport stream" signal that contains the TV channel currently being displayed on the TV.
  • the DEMOD demodulator receives a modulated carrier frequency from the tuner and outputs a demodulated audio / video signal to a first DMX1 multiplexer which generates a signal representative of the selected TV transmission channel in the tuner.
  • this TV transmission channel signal supplies directly via the link 9 a second multiplexer DMX2 for rendering on the one hand a video signal and on the other hand an audio signal.
  • a video decoder DEC VI performs a decoding for example from an MPEG2 or MPEG4 coding to a basic video signal which is the TV transmission channel readable by the television.
  • a decoder DEC A1 is used to reproduce the acceptable audio signal for the television.
  • the video decoder DEC VI generates a digital television signal accessible notably via an HDMI connector or other.
  • the DEC video decoder VI can also power a digital video encoder (DENC) 7 which converts the received digital video signal into a high quality analog signal compatible with TV standards. It is thus possible to have video signals in the following formats: Y / C, RGB, YUV or other.
  • the decoder DEC Al generates a digital audio signal of the S / PDIF type for example, which can be converted into a stereo type analog audio signal by means of a digital-to-analog audio converter 8.
  • the "timeshifting" function makes it possible to watch a program slightly delayed compared to the real time reception of this program.
  • a program is broadcast live, the user can pause the display for an indefinite time, and then resume playback of his program slightly deferred without missing a single moment of his program. More precisely, the user presses a "pause” button on his remote control 3.
  • the processor CPU interprets the infra red setpoint coming from the remote control and then automatically triggers the "timeshifting" function which inserts into the link 9 of FIG. NAND flash memory which records in real time the program arriving by the source SRC1.
  • the image is frozen so as to indicate to the user that the "timeshifting" function is activated. As seen in FIG.
  • the write pointer 5 in the NAND flash memory 4 records in real time the TV transmission channel signal from the DMX1 demultiplexer.
  • the "timeshifting" function is active only when the user activates it. It is also possible to provide a counter which interrupts the recording as soon as the recorded program exceeds a predetermined duration without the user has enabled delayed playback. In the same way, the recording is interrupted as soon as the Set Top Box is put to sleep.
  • the NAND flash memory 4 makes it possible for the playback pointer 6 to read the audio / video signal already recorded to the decoder DEC Al.
  • This time difference remains constant in the systems of the prior art.
  • reading is performed by the read pointer 6 so as to reduce this time offset. To do this, the reading is performed at a speed greater than the recording speed.
  • this reading speed is determined so that the video and audio broadcast of the program recorded at slightly accelerated speed does not disturb the user.
  • This diffusion rate can be a predetermined speed at a value that is considered comfortable for the user. For example, an acceleration of 1 to 2% per cent with respect to the recording speed may be considered.
  • the broadcast speed can therefore vary within a predefined range depending on the size of the program already recorded. This preset range can be from 1% to 10% of the recording speed. In particular, it is possible to determine the upper ceiling of the range as the broadcast speed at which the audio signal becomes incomprehensible to the user.
  • the reading is slightly accelerated automatically until it merges with the recording, and thus join the broadcast in real time.
  • the recording stops, the user resumes the normal course of real-time visualization.

Abstract

The invention relates to a method for recording and broadcasting a TV programme according to the principle of so-called timeshifting, in which the TV programme is recorded in real time on a memory medium, and during recording, this TV programme is broadcast delayed. According to the invention, the TV programme is broadcast at a broadcasting rate which is greater than the recording rate; this broadcasting rate being determined automatically.

Description

" Procédé et dispositif d'enregistrement et de diffusion vidéo par décalage temporel, dit « timeshifting »."  "Timeshifting video recording and broadcasting method and apparatus."
La présente invention se rapporte à un procédé et un dispositif pour enregistrer et diffuser un canal de transmission TV selon le principe dit de « timeshifting ». The present invention relates to a method and a device for recording and broadcasting a TV transmission channel according to the principle known as "timeshifting".
Le « timeshifting » provient de l'expression anglaise « time shifting », décalage temporel en français, et permet un enregistrement temps réel d'un programme télévisé tout en autorisant son visionnage en léger différé par rapport à sa diffusion temps réel.  The "timeshifting" comes from the English expression "time shifting", a time shift in French, and allows a real-time recording of a television program while allowing its viewing slightly delayed compared to its real-time broadcast.
Il est ainsi possible d'interrompre le visionnage d'un programme en direct, puis de le reprendre en léger différé sans rien manquer. La longueur d'enregistrement est toujours limitée par exemple à deux heures ou moins. Pour permettre une utilisation au delà de cette limite, on réalise la fonctionnalité de « TimeShifting » en enregistrant sur une mémoire que l'on utilise comme un tampon circulaire. Par exemple, en fonction de la durée prévue pour le « TimeShifting » (temps maximum entre pause et reprise sans perte de données), la taille du tampon circulaire peut atteindre 8 Go (8Mbits/s pendant 2 heures). Etant donné la nécessité d'avoir une mémoire de grande capacité, la fonctionnalité de « timeshifting » est apparue d'abord dans des enregistreurs de salon ou PVR (pour « Personal Video Recorder ») intégrant un disque dur (HDD) de grande capacité pour stocker le contenu de la mémoire tampon circulaire.  It is thus possible to interrupt the viewing of a live program, then resume it in a slight delay without missing anything. The recording length is always limited for example to two hours or less. To allow use beyond this limit, the functionality of "TimeShifting" is realized by recording on a memory that is used as a circular buffer. For example, depending on the expected duration of the "TimeShifting" (maximum time between pause and recovery without loss of data), the size of the circular buffer can reach 8 GB (8Mbits / s for 2 hours). Given the need for a high-capacity memory, the "timeshifting" feature first appeared in living room recorders or PVR (for "Personal Video Recorder") incorporating a high-capacity hard disk (HDD) for store the contents of the circular buffer.
La présente invention trouve une application particulièrement intéressante dans la technologie Flash NAND qui offre une capacité mémoire importante pour un coût raisonnable. Ce type de mémoire occupe peu d'espace et consomme moins d'énergie que les disques durs notamment. Une mémoire flash est une mémoire de masse à semi-conducteurs non volatile qui est facilement accessible en écriture et lecture. Elle conserve les informations qui y sont contenues même lorsqu'elle n'est plus alimentée électriquement. Cependant, une telle technologie ne permet pas la fonctionnalité d'enregistrement permanent comme dans les disques durs. C'est pour cela, on a introduit la notion de « timeshiftOnly » pour une fonctionnalité de « timeshifting » basée sur une mémoire flash. Par ailleurs, un autre inconvénient très important réside dans le fait qu'une mémoire flash NAND présente une durée moyenne entre deux pannes MTBF (pour « Mean Time Between Failures » en anglais) relativement faible, ceci limite le nombre de cycles d'écriture/effacement à quelques centaines de milliers alors que les disques durs proposent plusieurs millions. The present invention finds a particularly interesting application in Flash NAND technology which offers a large memory capacity for a reasonable cost. This type of memory occupies little space and consumes less energy than hard disks in particular. A flash memory is a nonvolatile semiconductor mass memory that is easily accessible for writing and reading. It keeps the information contained therein even when it is no longer electrically powered. However, such technology does not allow permanent recording functionality as in hard drives. This is why we introduced the notion of "timeshiftOnly" for a "timeshifting" feature based on flash memory. Furthermore, another very important disadvantage lies in the fact that a NAND flash memory has a mean duration between two MTBF faults (for "Mean Time Between Failures") relatively low, this limits the number of write cycles / erasure to a few hundred thousand while hard drives offer several million.
On note que la présente invention est d'un cadre plus large puisqu'elle peut s'appliquer à tout type de mémoire utilisée comme « buffer », telle que le disque dur ou la mémoire flash NOR.  Note that the present invention is of a broader scope since it can be applied to any type of memory used as a "buffer", such as hard disk or NOR flash memory.
Un but de la présente invention est de remédier aux inconvénients précités en proposant un procédé de « timeshifting » optimisant les cycles écriture/lecture. On atteint le but précité avec un procédé pour enregistrer et diffuser un canal de transmission TV selon le principe dit de « timeshifting », dans lequel : An object of the present invention is to overcome the aforementioned drawbacks by proposing a method of "timeshifting" optimizing the write / read cycles. The above purpose is achieved with a method for recording and broadcasting a TV transmission channel according to the so-called timeshifting principle, wherein:
- on enregistre en temps réel sur un support mémoire le canal de transmission TV,  the TV transmission channel is recorded in real time on a memory medium,
- pendant l'enregistrement, on diffuse en différé ledit canal de transmission TV.  during the recording, the said TV transmission channel is delayed.
Selon l'invention, le canal de transmission TV est diffusé à une vitesse de diffusion qui est supérieure à la vitesse d'enregistrement ; cette vitesse de diffusion étant déterminée de façon automatique.  According to the invention, the TV transmission channel is broadcast at a broadcasting speed which is higher than the recording speed; this diffusion rate being determined automatically.
Selon le principe dit de « timeshifting », le support mémoire est utilisé comme mémoire tampon ou « buffer » de sorte que le programme en cours d'enregistrement peut être visualisé avec un décalage temporel.  According to the so-called "timeshifting" principle, the memory medium is used as a buffer or "buffer" so that the program being recorded can be viewed with a time offset.
Un canal de transmission TV est un signal audio/vidéo relatif à une chaîne télévisée.  A TV transmission channel is an audio / video signal relating to a television channel.
En d'autres termes, avec le procédé selon l'invention, on effectue la lecture plus vite que l'écriture dans la mémoire de façon à ce que la lecture en différé rattrape la diffusion en temps réel. Cela permet de limiter les cycles écritures/lectures dans la mémoire. On préserve ainsi la durée de vie de la mémoire. Selon une caractéristique avantageuse de l'invention, la vitesse de diffusion peut être supérieure de 1 à 10 pourcents, mais elle est de préférence de 1 à 2 pourcents par rapport à la vitesse d'enregistrement. Avec une telle fourchette, l'utilisateur distingue peu ou pas l'accélération de la lecture. In other words, with the method according to the invention, the reading is performed faster than the writing in the memory so that the delayed reading catches the broadcast in real time. This makes it possible to limit the write / read cycles in the memory. This preserves the lifetime of the memory. According to an advantageous characteristic of the invention, the diffusion rate may be 1 to 10 percent higher, but it is preferably 1 to 2 percent higher than the recording rate. With such a range, the user distinguishes little or not the acceleration of the reading.
Cette vitesse de diffusion peut être prédéterminée à une valeur fixe ou bien déterminée en fonction de la durée du canal de transmission TV déjà enregistré dans le support mémoire. Dans ce second cas, on détecte la durée de programme déjà enregistré, puis on détermine la vitesse de diffusion qui permettrait de rattraper au plus vite la lecture en temps réel tout en respectant des critères de qualité ou de perçu par l'utilisateur. On peut notamment se cantonner à la plage prédéfinie.  This diffusion rate may be predetermined at a fixed value or determined according to the duration of the TV transmission channel already recorded in the memory medium. In this second case, the program duration already recorded is detected, then the diffusion rate is determined which would make it possible to catch the reading as quickly as possible in real time while respecting criteria of quality or perceived by the user. One can in particular be confined to the predefined range.
Selon un mode de mise en œuvre avantageux, le support mémoire est une mémoire flash NAND qui est notamment utilisé comme « buffer » circulaire où écriture ou enregistrement provoque l'effacement de données trop anciennes.  According to an advantageous embodiment, the memory medium is a NAND flash memory which is notably used as a circular buffer where writing or recording causes the erasure of data that are too old.
En particulier, lorsque le canal de transmission TV est diffusé via un écran d'affichage tel qu'un téléviseur, on arrête l'enregistrement et la diffusion en réponse à une consigne de mise en veille de cet écran d'affichage. Il s'agit là encore d'un mode de mise en œuvre permettant de préserver la durée de vie de la mémoire en évitant tout cycle écriture/lecture inutile. On prévoit également de lancer le processus de « timeshifting » selon l'invention uniquement en réponse à une consigne de l'utilisateur, par exemple en pressant sur le bouton « pause » de sa télécommande. On prévoit également d'arrêter l'enregistrement ou l'écriture dans la mémoire après un temps prédéterminé pendant lequel l'utilisateur n'a pas transmis une autre consigne. On se prémunit ainsi contre tout oubli par l'utilisateur dans un mode d'enregistrement permanent. Selon un autre aspect de l'invention, il est proposé un dispositif pour la réception et la diffusion vers un téléviseur de canaux de transmission TV selon le principe dit de « timeshifting » ; ce dispositif comprenant un support mémoire pour enregistrer en temps réel un canal de transmission TV, et pour diffuser en différé, pendant l'enregistrement, ledit canal de transmission TV. Selon l'invention, ce dispositif comprend un processeur configuré pour déterminer automatiquement une vitesse de diffusion qui est supérieure à la vitesse d'enregistrement, et pour diffuser le canal de transmission TV vers le téléviseur à cette vitesse de diffusion. In particular, when the TV transmission channel is broadcast via a display screen such as a television set, the recording and broadcasting is stopped in response to a standby instruction of this display screen. This is again an implementation mode to preserve the lifetime of the memory by avoiding any unnecessary write / read cycle. It is also planned to launch the "timeshifting" process according to the invention only in response to a user instruction, for example by pressing the "pause" button on its remote control. It is also planned to stop recording or writing in the memory after a predetermined time during which the user has not transmitted another instruction. This protects against all forgetting by the user in a permanent recording mode. According to another aspect of the invention, there is provided a device for receiving and broadcasting to a TV channel television transmission according to the so-called principle of "timeshifting"; this device comprising a memory medium for recording in real time a TV transmission channel, and for broadcasting, during recording, said TV transmission channel. According to the invention, this device comprises a processor configured to automatically determine a broadcast rate that is greater than the recording rate, and to broadcast the TV transmission channel to the television at this broadcast rate.
Par processeur configuré, on entend la présence d'un programme logiciel permettant au processeur d'exécuter des opérations.  Configured processor means the presence of a software program allowing the processor to perform operations.
La liaison entre le dispositif et le téléviseur est de préférence une liaison bidirectionnelle telle que par exemple un bus HDMI.  The connection between the device and the television is preferably a bidirectional link such as for example an HDMI bus.
D'autres avantages et caractéristiques de l'invention apparaîtront à l'examen de la description détaillée d'un mode de mise en œuvre nullement limitatif, et des dessins annexés, sur lesquels : Other advantages and characteristics of the invention will appear on examining the detailed description of a non-limiting embodiment, and the appended drawings, in which:
La figure 1 est une vue générale d'une Set Top Box reliée à un téléviseur; et  Figure 1 is a general view of a Set Top Box connected to a television; and
La figure 2 est une vue générale d'une chaîne de traitement de canaux vidéo selon l'invention.  Figure 2 is a general view of a video channel processing chain according to the invention.
Pour réaliser la fonctionnalité « timeshifting », la mémoire tampon ou « buffer » circulaire est constitué d'un composant de type flash NAND comme représenté en 4 sur la figure 2. Ce composant peut être une autre technologie telle qu'un disque dur, une mémoire flash NOR, ou autre. Le procédé selon l'invention est mis en œuvre dans la chaîne de traitement représentée sur la figure 2 afin de préserver le MTBF de la mémoire flash NAND 4 qui possède un nombre de cycles écriture/effacement assez faible. Cette chaîne de traitement de la figure 2 est gérée par un processeur CPU qui est configuré pour exécuter des instructions systèmes ou codes logiciels. Le tuner de la chaîne de traitement est alimenté par une source vidéo de transmission TV SRCl reliée par exemple à une antenne hertzienne dans le cas d'une réception de chaînes de la télévision numérique terrestre. Le tuner permet de sélectionner la fréquence du signal "transport stream" modulé qui contient la chaîne de télévision en cours d'affichage sur le téléviseur. To achieve the "timeshifting" functionality, the circular buffer or "buffer" consists of a NAND flash component as shown at 4 in FIG. 2. This component may be another technology such as a hard disk, NOR flash memory, or other. The method according to the invention is implemented in the processing chain shown in FIG. 2 in order to preserve the MTBF of the NAND flash memory 4 which has a relatively small number of write / erase cycles. This processing chain of Figure 2 is managed by a CPU processor that is configured to execute system instructions or software codes. The tuner of the processing chain is powered by a video transmission SRCl TV source connected for example to a radio antenna in the case of reception of digital terrestrial television channels. The tuner is used to select the frequency of the modulated "transport stream" signal that contains the TV channel currently being displayed on the TV.
Le démodulateur DEMOD reçoit une fréquence porteuse modulée depuis le tuner et restitue un signal audio/vidéo démodulé vers un premier multiplexeur DMX1 qui génère un signal représentatif du canal de transmission TV sélectionné dans le tuner. Selon l'invention, lorsque l'utilisateur regarde un programme télévisé sans la fonction « timeshifting », ce signal de canal de transmission TV alimente directement via la liaison 9 un second multiplexeur DMX2 permettant de restituer d'une part un signal vidéo et d'une autre part un signal audio. Un décodeur vidéo DEC VI réalise un décodage par exemple depuis un codage MPEG2 ou MPEG4 vers un signal vidéo de base qui est le canal de transmission TV lisible par le téléviseur. En ce qui concerne le signal audio, on utilise un décodeur DEC Al pour restituer le signal audio acceptable pour le téléviseur. The DEMOD demodulator receives a modulated carrier frequency from the tuner and outputs a demodulated audio / video signal to a first DMX1 multiplexer which generates a signal representative of the selected TV transmission channel in the tuner. According to the invention, when the user watches a television program without the "timeshifting" function, this TV transmission channel signal supplies directly via the link 9 a second multiplexer DMX2 for rendering on the one hand a video signal and on the other hand an audio signal. A video decoder DEC VI performs a decoding for example from an MPEG2 or MPEG4 coding to a basic video signal which is the TV transmission channel readable by the television. As far as the audio signal is concerned, a decoder DEC A1 is used to reproduce the acceptable audio signal for the television.
Le décodeur vidéo DEC VI génère un signal de télévision numérique accessible notamment via un connecteur HDMI ou autre. Le décodeur vidéo DEC VI peut par ailleurs alimenter un encodeur numérique vidéo (DENC) 7 qui convertit le signal vidéo numérique reçu en un signal analogique de haute qualité compatible avec les standards TV. On peut ainsi disposer de signaux vidéo aux formats : Y/C, RVB, YUV ou autre. The video decoder DEC VI generates a digital television signal accessible notably via an HDMI connector or other. The DEC video decoder VI can also power a digital video encoder (DENC) 7 which converts the received digital video signal into a high quality analog signal compatible with TV standards. It is thus possible to have video signals in the following formats: Y / C, RGB, YUV or other.
Le décodeur DEC Al génère un signal audio numérique de type S/PDIF par exemple, qui peut être converti en signal audio analogique de type stéréo au moyen d'un convertisseur audio numérique-analogique 8.  The decoder DEC Al generates a digital audio signal of the S / PDIF type for example, which can be converted into a stereo type analog audio signal by means of a digital-to-analog audio converter 8.
La fonction « timeshifting » permet de regarder un programme en léger différé par rapport à la réception temps réel de ce programme. Bien qu'un programme soit diffusé en direct, l'utilisateur peut mettre en pause la visualisation pour un moment indéterminé, puis reprendre la lecture de son programme en léger différé sans manquer un seul instant de son programme. Plus précisément, l'utilisateur appuie sur un bouton « pause » de sa télécommande 3. Le processeur CPU interprète la consigne infra rouge provenant de la télécommande puis déclenche automatiquement la fonction « timeshifting » qui insère dans la liaison 9 de la figure 2, la mémoire flash NAND qui enregistre en temps réel le programme arrivant par la source SRC1. Par contre, au niveau du téléviseur, l'image est figée de façon à indiquer à l'utilisateur que la fonction « timeshifting » est activée. Comme on le voit sur la figure 2, le pointeur d'écriture 5 dans la mémoire flash NAND 4 enregistre en temps réel le signal de canal de transmission TV provenant du démultiplexeur DMX1. Dans ce mode de réalisation, la fonction « timeshifting » est active uniquement lorsque l'utilisateur l'active. On peut également prévoir un compteur qui interrompt l'enregistrement dès lors que le programme enregistré dépasse une durée prédéterminée sans que l'utilisateur n'ait activé la lecture différée. De la même manière on interrompt l'enregistrement dès que la Set Top Box est mise en veille. The "timeshifting" function makes it possible to watch a program slightly delayed compared to the real time reception of this program. Although a program is broadcast live, the user can pause the display for an indefinite time, and then resume playback of his program slightly deferred without missing a single moment of his program. More precisely, the user presses a "pause" button on his remote control 3. The processor CPU interprets the infra red setpoint coming from the remote control and then automatically triggers the "timeshifting" function which inserts into the link 9 of FIG. NAND flash memory which records in real time the program arriving by the source SRC1. On the other hand, at the level of the television, the image is frozen so as to indicate to the user that the "timeshifting" function is activated. As seen in FIG. 2, the write pointer 5 in the NAND flash memory 4 records in real time the TV transmission channel signal from the DMX1 demultiplexer. In this embodiment, the "timeshifting" function is active only when the user activates it. It is also possible to provide a counter which interrupts the recording as soon as the recorded program exceeds a predetermined duration without the user has enabled delayed playback. In the same way, the recording is interrupted as soon as the Set Top Box is put to sleep.
Dès que l'utilisateur est de retour et appuie sur la touche « play » par exemple, la mémoire flash NAND 4 permet en même temps la lecture par le pointeur de lecture 6 du signal audio/vidéo déjà enregistré vers le décodeur vidéo DEC Al . Cela signifie que l'enregistrement par le pointeur de lecture 5 et la lecture par le pointeur de lecture 6 sont réalisés en parallèle ; l'enregistrement ayant débuté un instant auparavant. Il existe donc un décalage temporel entre le début de l'enregistrement (appui sur le bouton « pause ») et le début de la lecture (appui sur le bouton « play » de la télécommande). Ce décalage temporel reste constant dans les systèmes de l'art antérieur. Mais dans la présente invention, on réalise la lecture par le pointeur de lecture 6 de façon réduire ce décalage temporel . Pour ce faire, on réalise la lecture à une vitesse supérieure à la vitesse d'enregistrement. De préférence, cette vitesse de lecture est déterminée de façon à ce que la diffusion vidéo et audio du programme enregistré en vitesse légèrement accélérée ne perturbe pas l'utilisateur. Cette vitesse de diffusion peut être une vitesse prédéterminée à une valeur que l'on estime confortable pour l'utilisateur. Par exemple une accélération de 1 à 2% pourcents par rapport à la vitesse d'enregistrement peut être envisagée. On peut également prévoir une vitesse de diffusion qui est déterminée en fonction de la taille ou durée de programme déjà enregistré. Dans ce cas, on applique une accélération importante lorsque le programme déjà enregistré dépasse un seuil supérieur donné. On applique une accélération modérée lorsque le programme déjà enregistré reste en dessous d'un seuil inférieur donné. La vitesse de diffusion peut donc varier dans une plage prédéfinie en fonction de la taille du programme déjà enregistré. Cette plage prédéfinie peut aller de 1% à 10% de la vitesse d'enregistrement. On peut notamment envisager de déterminer le plafond supérieur de la plage comme étant la vitesse de diffusion à laquelle le signal audio devient incompréhensible pour l'utilisateur.  As soon as the user is back and presses the "play" key for example, the NAND flash memory 4 at the same time makes it possible for the playback pointer 6 to read the audio / video signal already recorded to the decoder DEC Al. This means that the recording by the read pointer 5 and the read by the read pointer 6 are performed in parallel; the recording having started a moment before. There is therefore a time lag between the beginning of the recording (pressing the "pause" button) and the start of playback (pressing the "play" button on the remote control). This time difference remains constant in the systems of the prior art. But in the present invention, reading is performed by the read pointer 6 so as to reduce this time offset. To do this, the reading is performed at a speed greater than the recording speed. Preferably, this reading speed is determined so that the video and audio broadcast of the program recorded at slightly accelerated speed does not disturb the user. This diffusion rate can be a predetermined speed at a value that is considered comfortable for the user. For example, an acceleration of 1 to 2% per cent with respect to the recording speed may be considered. It is also possible to provide a broadcasting speed which is determined according to the size or duration of the program already recorded. In this case, a significant acceleration is applied when the already registered program exceeds a given upper threshold. A moderate acceleration is applied when the already recorded program remains below a given lower threshold. The broadcast speed can therefore vary within a predefined range depending on the size of the program already recorded. This preset range can be from 1% to 10% of the recording speed. In particular, it is possible to determine the upper ceiling of the range as the broadcast speed at which the audio signal becomes incomprehensible to the user.
Avec le procédé selon l'invention, la lecture est légèrement accélérée de façon automatique jusqu'à se confondre avec l'enregistrement, et donc rejoindre la diffusion en temps réel. Dans ce cas, l'enregistrement cesse, l'utilisateur reprend le cours normal de visualisation temps réel . On limite ainsi les cycles d'enregistrement/lecture de la mémoire flash NAND. Bien sûr, l'invention n'est pas limitée aux exemples qui viennent d'être décrits et de nombreux aménagements peuvent être apportés à ces exemples sans sortir du cadre de l'invention. With the method according to the invention, the reading is slightly accelerated automatically until it merges with the recording, and thus join the broadcast in real time. In this case, the recording stops, the user resumes the normal course of real-time visualization. This limits the recording / playback cycles of the NAND flash memory. Of course, the invention is not limited to the examples that have just been described and many adjustments can be made to these examples without departing from the scope of the invention.

Claims

REVENDICATIONS
1. Procédé pour enregistrer et diffuser un canal de transmission TV selon le principe dit de « timeshifting », dans lequel : A method for recording and broadcasting a TV transmission channel according to the so-called timeshifting principle, wherein:
- on enregistre en temps réel sur un support mémoire le canal de transmission TV,  the TV transmission channel is recorded in real time on a memory medium,
- pendant l'enregistrement, on diffuse en différé ledit canal de transmission TV, le canal de transmission TV étant diffusé à une vitesse de diffusion supérieure à la vitesse d'enregistrement ; cette vitesse de diffusion étant déterminée de façon automatique,  during the recording, said TV transmission channel is delayed, the TV transmission channel being broadcast at a broadcasting speed higher than the recording speed; this diffusion speed being determined automatically,
caractérisé en ce que la vitesse de diffusion est supérieure de 1 à 10 pourcents par rapport à la vitesse d'enregistrement.  characterized in that the diffusion rate is 1 to 10 percent higher than the recording rate.
2. Procédé selon la revendication 1, caractérisé en ce que la vitesse de diffusion est supérieure de 1 à 2 pourcents, par rapport à la vitesse d'enregistrement. 2. Method according to claim 1, characterized in that the diffusion rate is 1 to 2 percent higher, relative to the recording speed.
3. Procédé selon la revendication 1 ou 2, caractérisé en ce que la vitesse de diffusion est prédéterminée. 3. Method according to claim 1 or 2, characterized in that the diffusion rate is predetermined.
4. Procédé selon l'une quelconque des revendications 1 à 3, caractérisé en ce que la vitesse de diffusion est déterminée en fonction de la durée du canal de transmission TV déjà enregistré dans le support mémoire. 4. Method according to any one of claims 1 to 3, characterized in that the diffusion rate is determined according to the duration of the TV transmission channel already recorded in the memory medium.
5. Procédé selon l'une quelconque des revendications précédentes, caractérisé en ce que le support mémoire est une mémoire flash NAND. 5. Method according to any one of the preceding claims, characterized in that the memory medium is a NAND flash memory.
6. Procédé selon l'une quelconque des revendications précédentes, caractérisé en ce que le canal de transmission TV étant diffusé via un écran d'affichage, on arrête l'enregistrement et la diffusion en réponse à une consigne de mise en veille de cet écran d'affichage. 6. Method according to any one of the preceding claims, characterized in that the TV transmission channel being broadcast via a display screen, stopping the recording and broadcasting in response to a standby instruction of this screen display.
7. Dispositif pour la réception et la diffusion vers un téléviseur de canaux de transmission TV selon le principe dit de « timeshifting » ; ce dispositif comprenant un support mémoire pour enregistrer en temps réel un canal de transmission TV, et pour diffuser en différé, pendant l'enregistrement, ledit canal de transmission TV, 7. Device for receiving and broadcasting to a TV channel television transmission according to the so-called principle of "timeshifting"; this device comprising a memory medium for recording in real time a channel of transmission, and to broadcast, during the recording, said TV transmission channel,
caractérisé en ce qu'il comprend un processeur configuré pour déterminer automatiquement une vitesse de diffusion qui est supérieure de 1 à 10 pourcents par rapport à la vitesse d'enregistrement, et pour diffuser le canal de transmission TV vers le téléviseur à cette vitesse de diffusion.  characterized in that it comprises a processor configured to automatically determine a broadcast rate that is 1 to 10 percent higher than the recording rate, and to broadcast the TV transmission channel to the television at this broadcast rate .
8. Dispositif selon la revendication 7, caractérisé en ce que le support mémoire est une mémoire flash NAND. 8. Device according to claim 7, characterized in that the memory medium is a NAND flash memory.
9. Dispositif selon la revendication 7 ou 8, caractérisé en ce que le processeur est configuré pour arrêter l'enregistrement et la diffusion en réponse à une consigne de mise en veille du téléviseur ; la liaison entre le dispositif et le téléviseur étant une liaison bidirectionnelle. 9. Device according to claim 7 or 8, characterized in that the processor is configured to stop the recording and broadcasting in response to a setting of the TV standby; the connection between the device and the television being a bidirectional link.
10. Dispositif selon la revendication 9, caractérisé en ce que la liaison bidirectionnelle est un bus HDMI. 10. Device according to claim 9, characterized in that the bidirectional link is an HDMI bus.
PCT/FR2010/052890 2009-12-23 2010-12-22 Method and device for video recording and broadcasting by so-called time shifting WO2011077057A1 (en)

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FR0959449A FR2954650B1 (en) 2009-12-23 2009-12-23 "METHOD AND DEVICE FOR VIDEO RECORDING AND BROADCASTING BY TIME SHIFT, SAID" TIMESHIFTING "."

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Citations (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US5438423A (en) * 1993-06-25 1995-08-01 Tektronix, Inc. Time warping for video viewing
EP0594241B1 (en) * 1992-10-19 1999-05-06 Koninklijke Philips Electronics N.V. Arrangement for storing an information signal in a memory and retrieving the information signal from said memory
EP1046288B1 (en) * 1998-01-07 2003-04-23 Thomson Licensing S.A. Video signal processing method and apparatus
US20030165324A1 (en) * 1997-12-23 2003-09-04 O'connor Dennis M. Time shifting by concurrently recording and playing a data stream
EP1758390A2 (en) * 1997-12-23 2007-02-28 Intel Corporation Method of time shifting to simultaneously record and play a data stream
US20070183744A1 (en) * 2004-03-08 2007-08-09 Sanyo Electric Co,. Ltd. Mobile terminal, method for recording/reproducing broadcast in mobile terminal, and broadcast recording/reproducing program
US20070223870A1 (en) * 2006-03-23 2007-09-27 Seagate Technology Llc Single board digital video system

Family Cites Families (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP1739676A1 (en) * 2005-06-29 2007-01-03 Hitachi, Ltd. Digital broadcasting receiving device and digital information receiving device, and playback method

Patent Citations (8)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP0594241B1 (en) * 1992-10-19 1999-05-06 Koninklijke Philips Electronics N.V. Arrangement for storing an information signal in a memory and retrieving the information signal from said memory
US5438423A (en) * 1993-06-25 1995-08-01 Tektronix, Inc. Time warping for video viewing
US5438423C1 (en) * 1993-06-25 2002-08-27 Grass Valley Us Inc Time warping for video viewing
US20030165324A1 (en) * 1997-12-23 2003-09-04 O'connor Dennis M. Time shifting by concurrently recording and playing a data stream
EP1758390A2 (en) * 1997-12-23 2007-02-28 Intel Corporation Method of time shifting to simultaneously record and play a data stream
EP1046288B1 (en) * 1998-01-07 2003-04-23 Thomson Licensing S.A. Video signal processing method and apparatus
US20070183744A1 (en) * 2004-03-08 2007-08-09 Sanyo Electric Co,. Ltd. Mobile terminal, method for recording/reproducing broadcast in mobile terminal, and broadcast recording/reproducing program
US20070223870A1 (en) * 2006-03-23 2007-09-27 Seagate Technology Llc Single board digital video system

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