Abstract:
A method and apparatus for managing recording of broadcast data is disclosed. In one embodiment, the invention includes providing the broadcast data to a video recording device and delaying the broadcast data that is provided to the video recording device sufficient to allow for the finding of an indicator and the transmitting of a command to the video recording device. The broadcast data is recorded using the video recording device and monitored for a commercial indicator and for a program indicator. If a commercial indicator is found, a command is transmitted to the video recording device to stop recording. If a commercial indicator is not found, recording continues. If a program indicator is found, a command is transmitted to the video recording device to resume recording and if a program indicator is not found, the recording stop continues.

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
     This application is a divisional of prior U.S. patent application Ser. No. 08/940,355, filed Sep. 30, 1997 now U.S. Pat. No. 6,226,441 B1, and assigned to the assignee of the present application. 
    
    
     FIELD OF THE INVENTION 
     The present invention relates to the field of entertainment systems. Specifically, the present invention relates to a method and apparatus for recording broadcast data without commercials. 
     BACKGROUND OF THE INVENTION 
     Video recording and playback devices are widespread in use and are operable in a record mode to record broadcast data on a recordable medium. In a playback mode, the video recording and playback device is operable to couple the recorded broadcast data to a display device where it may be viewed at the convenience of the viewer. The use of video recording and playback devices has enabled viewers of broadcast data to control their viewing habits. 
     In the past, it was necessary for a viewer to manually stop and restart the record mode to prevent the recording of undesired portions of broadcast data such as advertising commercials which are typically interspread throughout desired program data. In order to provide an additional degree of convenience, the video equipment industry has attempted to provide devices that control the video recording and playback device in its record mode to automatically inhibit the recording of unwanted advertising commercials. 
     One technique used in the past to detect commercials was the monitoring of the amplitude of the video and audio signal of the broadcast data for a drop of the video signal to a black level and a drop of the audio signal to a zero sound level. One disadvantage, however, on relying on a drop of the video and audio signals to indicate the broadcast of a commercial is that video and audio signals may also drop during the broadcast of program data, thus falsely indicating the broadcast of a commercial. This produces the undesirable result of taking the video recording and playback device out of the record mode during the broadcast of program data. 
     SUMMARY OF THE INVENTION 
     A method and apparatus for managing recording of broadcast data is disclosed. In one embodiment, the invention includes providing the broadcast data to a video recording device and delaying the broadcast data that is provided to the video recording device sufficient to allow for the finding of an indicator and the transmitting of a command to the video recording device. The broadcast data is recorded using the video recording device and monitored for a commercial indicator and for a program indicator. If a commercial indicator is found, a command is transmitted to the video recording device to stop recording. If a commercial indicator is not found, recording continues. If a program indicator is found, a command is transmitted to the video recording device to resume recording and if a program indicator is not found, the recording stop continues. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     The present invention is illustrated by way of example and not by way of limitation in the figures of the accompanying drawings, in which like references indicate similar elements and in which: 
     FIG. 1 is a block diagram illustrating the system components of one embodiment of an entertainment system according to the present invention; 
     FIG. 2 is a block diagram illustrating one embodiment of a system controller according to the present invention; 
     FIG. 3 is a block diagram of modules implementing an embodiment of the present invention; 
     FIG. 4 is a block diagram illustrating an embodiment of the program data analyzer according to the present invention; 
     FIG. 5 illustrates a first graphical user interface according to an embodiment of the present invention; 
     FIG. 6 illustrates a second graphical user interface according to an embodiment of the present invention; 
     FIG. 7 is a flow chart illustrating a first method for managing recording broadcast data according to an embodiment of the present invention; and 
     FIG. 8 is a flow chart illustrating a second method for managing recording of broadcast data according to an embodiment of the present invention. 
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
     FIG. 1 is a block diagram illustrating system components of an entertainment system  100  according to one embodiment of the present invention. The entertainment system includes a common input/output (I/O) bus  110  that connects the system components in the entertainment system  100  together. It should be appreciated that the common I/O bus  110  is illustrated to simplify the routing of signals between the computer system components. The common I/O bus  110  may represent a plurality of known mechanisms and techniques for routing I/O signals between the computer system components. For example, the common I/O bus  110  may include an appropriate number of independent audio “patch” cables that rout audio signals, coaxial cables that rout video signals, two-wire serial lines or infrared or radio frequency transceivers that rout control signals, or other routing mechanisms that rout other signals. 
     In the illustrated embodiment, the entertainment system  100  includes a television/monitor  121 , video recorder/playback device  122 , digital video disk (DVD) recorder/playback device  123 , audio/video tuner and amplifier  124 , audio playback/recorder device  125 , and compact disk player  126  coupled to the common I/O bus. The video recorder/playback device  122 , DVD recorder/playback device  123 , audio playback/recorder device  125 , and compact disk player  126  may be single disk or single cassette devices, or alternatively may be multiple disk or multiple cassette devices. 
     In addition, the entertainment system  100  includes a speaker system  131 , microphone  132 , video camera  133 , and a wireless I/O control device  134 . In one embodiment, wireless I/O control device  134  is an entertainment system remote control unit which communicates with the components of the entertainment system  100  through IR signals. In another embodiment, wireless I/O control device  134  may be a wireless keyboard and cursor positioning device that communicates with the components of entertainment system  100  through IR signals or RF signals. In yet another embodiment, wireless I/O control device  134  may be an IR remote control device similar in appearance to a typical entertainment system remote control with the added feature of a track-ball, which allows a user to position a cursor on a display of the entertainment system  100 . 
     The entertainment system  100  also includes a system controller  140 . According to one embodiment of the present invention, the system controller  140  operates to receive broadcast data available from a plurality of broadcast data sources and analyze the broadcast data to determine which portion of the broadcast data contains commercials and which portions of the programming data do not contain commercials. According to another embodiment of the present invention, system controller  140  is configured to control a wide variety of features associated with each of the system components. As shown in FIG. 1, system controller  140  is coupled, either directly or indirectly, to each of the system components, as necessary, through I/O bus  110 . In one embodiment, in addition to or in place of I/O bus  110 , system controller  140  is configured with a wireless communication transmitter (or transceiver), which is capable of communicating with the system components via IR signals or RF signals  110 ′. Regardless of the control medium, the system controller  140  is configured to control one or more of the entertainment system components of the entertainment system  100 , although it is understood that each of the components may be individually controlled with wireless I/O control device  134 . 
     As illustrated in FIG. 1, entertainment system  100  may be configured to receive broadcast data from a wide variety of sources. In one embodiment, entertainment system  100  receives broadcast data from any or all of the following sources: cable broadcast  141 , satellite broadcast  142  (e.g., via a satellite dish), very high frequency (VHF) or ultra high frequency (UHF) radio frequency communication of the broadcast networks  143  (e.g., via an aerial antenna), telephone/computer network interface  144 , and/or information stored locally at system controller  140  or another component of the entertainment system  100 . Further, it will be appreciated by one skilled in the art, that cable broadcast input  141 , satellite broadcast input  142  and VHF/UHF input  143  may receive input from digital broadcast programming and digital cable programming. The broadcast data may be received by the entertainment system  100  via the audio/video tuner and amplifier  124 , the system controller  140 , or other system components or combination of system components. 
     Although the present invention is described in the context of the exemplary embodiments presented in the figures, those skilled in the art will appreciate that the present invention is not limited to these embodiments and may be practiced in a variety of alternate embodiments. Accordingly, the innovative features of the present invention may be practiced in a system of greater or lesser complexity than that of the system depicted in FIG.  1 . 
     FIG. 2 is a block diagram illustrating an embodiment of a computer system  200  that may be used to implement the system controller  140  according to the present invention. The computer system  200  includes a processor  201  that processes digital data signals. The processor  201  may be a complex instruction set computer (CISC) microprocessor, a reduced instruction set computing (RISC) microprocessor, a very long instruction work (VLIW) microprocessor, a processor implementing a combination of instruction sets, or other processor device. FIG. 2 shows an example of the present invention implemented on a single processor computer system  200 . However, it is understood that the present invention may be implemented in a computer system having multiple processors. The processor  201  is coupled to a CPU bus  210  which transmits data signals between processor  201  and other components in the computer system  200 . 
     As an example, memory  213  may be a dynamic random access memory (DRAM) device, a static random access memory (SRAM) device, or other memory device. The memory  213  stores information or other intermediate data signals that are executed by the processor  201 . A cache memory  202  resides inside processor  201  that stores information or other intermediate data signals that is stored in memory  213 . The cache  202  speeds up memory accesses by the processor  201  by taking advantage of its locality of access. In an alternate embodiment of the computer system  200 , the cache  202  or a second cache resides external to the processor  201 . 
     A bridge memory controller  211  is coupled to the CPU bus  210  and the memory  213 . The bridge memory controller  211  directs data signals between the processor  201 , the memory  213 , and other components in the computer system  200  and bridges the data signals from these components to a first I/O bus  220 . 
     The first I/O bus  220  may be a single bus or a combination of multiple buses. As an example, the first I/O bus  220  maybe a high performance I/O bus that operates at high throughput rates. The first I/O bus  220  may include for example a Peripheral Components Interconnect (PCI) bus, a Personal Computer Memory Card International Association (PCMCIA) bus, a NuBus, or other buses. The first I/O bus  220  provides communication links between components in the computer system  200 . A network controller  221  links the computer system  200  to a network of computers and supports communication among the machines. A display device controller  222  is coupled to the first I/O bus  220 . The display device controller  222  allows coupling of a display device to the computer system  200  and acts as an interface between the display device and the computer system  200 . The display device controller may be a monochrome display adapter (MDA) card, a color graphics adapter (CGA) card, an enhanced graphics adapter (EGA) card, an extended graphics array (XGA) card or other display device controller. The display device may be a television set, a computer monitor, a flat panel display or other display device. The display device receives data signals from the processor  201  through the display device controller  222  and displays the information and data signals to the user of the computer system  200 . 
     A second I/O bus  230  may be a single bus or a combination of multiple buses. The second I/O bus  230  may include an Industry Standard Architecture (ISA) bus, an Extended Industry Standard Architecture (EISA) bus, or other buses. The second I/O bus  230  provides communication links between components in the computer system  200 . A keyboard interface  232  may be a keyboard controller or other keyboard interface. The keyboard interface  232  may be a dedicated device or can reside in another device such as a bus controller or other controller. The keyboard interface  232  allows coupling of a keyboard to the computer system  200  and transmits data signals from a keyboard to the computer system  200 . A data storage device  231  may be a hard disk drive, a floppy disk drive, a CD-ROM device, a flash memory device or other mass storage device. An audio controller  233  operates to coordinate the recording and playing of sounds is also coupled to the I/O bus  230 . A wireless communications interface  234  may be an IR transceiver or a RF transceiver for transmitting and receiving signals between system components of the entertainment system  100  (shown in FIG.  1 ). 
     A bus bridge  223  couples the first I/O bus  220  to the second I/O bus  230 . The bus bridge  223  operates to buffer and bridge data signals between the first I/O bus  220  and the second I/O bus  230 . 
     According to one embodiment, managing the recording of broadcast data is performed by the computer system  200  in response to the processor  201  executing sequences of instructions contained in the memory  213 . Such instructions may be read into the memory  213  from other computer-readable mediums such as data storage device  231  or from a computer connected to the network via the network controller  211 . Execution of the sequences of instructions contained in the memory  213  causes the processor to manage the recording of broadcast data, as will be described hereafter. In alternative embodiments, hard-wire circuitry may be used in place of or in combination with software instructions to implement the present invention. Thus, the present invention is not limited to any specific combination of hardware circuitry and software. 
     FIG. 3 is a block diagram illustrating an embodiment of modules of a broadcast data recording manager  300 , according to the present invention. The modules may be implemented by software, hardware, or a combination of both hardware and software. Block  310  represents a transaction processor that receives a request to record broadcast data without commercials. The transaction processor includes a log  311  that records programming information about the broadcast data that is to be recorded. The transaction processor also includes an external interface  312  that forwards the programming information recorded in the log  311  to an external computer system. According to an embodiment of the present invention, the external interface  311  may forward the programming information through a network via the network controller  221  (shown in FIG.  2 ). The log  311  and the external interface  312  may be implemented by any known circuitry or technique. 
     Block  320  represents a broadcast data receiver. The broadcast data receiver  320  operates to receive broadcast data from a plurality of sources including analog and digital broadcast data such as cable broadcast input, satellite broadcast input, and VHF/UHF input. The broadcast data receiver  320  may comprise a video card with a tuner and amplifier, a connection to cable or satellite broadcast sources, or other circuitry. According to an embodiment of the present invention, the broadcast data receiver  320  operates to digitize broadcast data received in analog format before displaying the broadcast data on a display device. 
     Block  330  represents a broadcast data analyzer. The broadcast data analyzer  330  is coupled to the transaction processor  310  and the broadcast data receiver  320 . The broadcast data analyzer  330  receives requests from the transaction processor  310  to record programming data received from the broadcast data receiver  320 . The broadcast data analyzer  330  monitors the broadcast data for commercial indicators and program indicators. Commercial indicators indicate that a commercial is broadcasted or will be broadcasted on the broadcast data. A commercial indicator may be, for example, a message in the VBI stating that a commercial will be broadcasted on the broadcast data, a fade to back, or an increase in the volume signal. Program indicators indicate that a program is broadcasted or will be broadcasted on the broadcast data. A program indicator may be, for example, a message in the VBI stating that a program is will be broadcasted on the broadcast data, a fade to black after a commercial, or a decrease in the volume signal. From the commercial indicators and program indicators, the broadcast data analyzer  330  makes a determination as to which broadcast data is a commercial and which broadcast data is program data. 
     Block  340  represents a recorder interface  340 . According to an embodiment of the present invention, the recorder interface  340  communicates with the wireless communication interface  234  (shown in FIG. 2) instructing the wireless communication interface to transmit commands to the video recording and playback device  122  (shown in FIG.  1 ). The recorder interface  340  is coupled to the broadcast data analyzer  330  and is informed by the broadcast data analyzer  330  as to which broadcast data is a commercial and which broadcast data is program data. The recorder interface  340  instructs the wireless communication interface  234  to transmit the appropriate commands to the video recording and playback device  122  such that the video recording and playback device  122  may make a recording of broadcast data without commercials. It should be appreciated that the recorder interface  340  may program the video recording and playback device  122  using any known technique to make a recording of the broadcast data without commercials. The transaction processor  310 , broadcast data receiver  320 , broadcast data analyzer  330 , and the recorder interface  340  may be implemented by any known circuitry or technique. 
     FIG. 4 is a block diagram illustrating an embodiment of modules of a broadcast data analyzer  330  according to the present invention. The modules may be implemented by software, hardware, or a combination of both hardware and software. Block  440  represents a data manager. Block  410  represents a VBI analyzer. Block  420  represents a volume analyzer. Block  430  represents a background analyzer. The data manager  440  is coupled to the VBI analyzer  410 , volume analyzer  420 , and background analyzer  430 . The data manager  440  receives the broadcast data from the broadcast data receiver  320  (shown in FIG. 3) and forwards the broadcast data to the VBI analyzer  410 , volume analyzer  420 , and background analyzer  430  to detect commercial and program indicators. The VBI analyzer  410  operates to read the VBI of analog broadcast data. Messages in the VBI that announce that a commercial is to be broadcasted and that a program is to resume serve as commercial and program indicators to the VBI analyzer. When the VBI analyzer  410  finds a message in the VBI that indicates that a commercial is to be broadcasted in the broadcast data, the VBI analyzer  410  sends a VBI commercial detection signal to the data manager  440 . When the VBI analyzer  410  finds a message in the VBI that indicates that program data is to be broadcasted in the broadcast data, the VBI analyzer  420  sends a VBI program detection signal to the data manager  440 . 
     The volume analyzer  420  operates to monitor the amplitude of the audio signal in analog and digital broadcast data. Increases and decreases in volume level in broadcast data serve as commercial and program indicators to the volume analyzer  420 . When the volume level in the broadcast data increases beyond a reference level, the volume analyzer  420  sends a volume commercial detection signal to the data manager  440 . When the volume level in the broadcast data returns to the reference level, the volume analyzer  420  sends a volume program detection signal to the data manager  440 . According to an embodiment of the present invention, the volume analyzer  420  calculates an average volume level of previously broadcasted program data and defines the reference level with that value. When the volume level of the broadcast data exceeds the average level of previously broadcasted program data, the volume analyzer  420  informs the data manager  440  that a commercial is being broadcasted. Similarly, when the volume level of the broadcast data returns to the reference level after exceeding the reference level, the volume analyzer  420  informs the data manager  440  that program data is being broadcasted. 
     The background analyzer  430  operates to monitor the amplitude of the video signal in the analog and digital broadcast data. A drop in the video signal to a black level for a predetermined period of time serves as a commercial and program indicator to the background analyzer. When the video signal drops to a black level for a predetermined period of time during when a black background is broadcasted, the background analyzer  430  sends a background commercial/program detection signal to the data manager  440 . 
     The data manager  440  receives the VBI commercial and program detection signals from the VBI analyzer  410 , volume commercial and program detection signals from the volume analyzer  420 , and background commercial/program detection signals from the background analyzer  430  and makes a determination from the signals as to whether a commercial is to be broadcasted in the broadcast data or whether program data is to be broadcasted in the broadcast data. According to an embodiment of the present invention, the data manager  440  relies only on the VBI commercial and program detection signals from the VBI analyzer  410  to determine whether a commercial or program data is being broadcasted when VBI commercial and program detection signals are received from the VBI analyzer  410 . When VBI commercial and program detection signals are not received from the VBI analyzer  410 , the data manager  440  relies on the volume commercial and program detection signals from the volume analyzer  420  and the background commercial/program detection signal from the background analyzer  420  to determine whether a commercial or program data is being broadcasted. 
     In a preferred embodiment of the present invention, the broadcast data analyzer  330  includes the VBI analyzer  410 , the volume analyzer  420 , and the background analyzer  430 . However, it should be appreciated that broadcast data analyzer  330  may be configured with any one or combination of the VBI analyzer  410 , the volume analyzer  420 , and the background analyzer  430 . The VBI analyzer  410 , the volume analyzer  420 , and the background analyzer  430  may be configured using any known technique. 
     According to an embodiment of the present invention, when the data manager  440  relies on the volume commercial and program detection signals from the volume analyzer  420  and the background commercial/program detection signal from the background analyzer to determine whether a commercial or program data is being broadcasted, an amount of time is required for the broadcast data to be analyzed before the appropriate commands can be conveyed to the recording and playback device  122  (shown in FIG. 1) to exit or enter the record mode. According to one embodiment of the present invention, a delay unit is coupled to the video recording and playback device  122  that provides a delay in time before broadcast data is sent to the video recording and playback device  122 . The delay in time allows the broadcast data analyzer  330  to determine whether a commercial or program data is being broadcasted and convey the appropriate commands to the video recording and playback device  122  to produce a recording of the broadcast data without commercials. It should be appreciated that the delay unit may be configured on the video recording and playback device  122  or external to the video recording and playback device  122 . The delay unit may be implemented by any known circuitry or technique. 
     According to a second embodiment of the present invention, the video recording and playback device  122  is programmed to continue recording the broadcast data after the video signal has dropped to a black level until the data manager  440  is able to determine whether the broadcast data broadcasted after the video signal has dropped to the black level is a commercial or program data. If the broadcast data is determined to be program data, the video recording and playback device  122  is programmed to continue recording the broadcast data. If the broadcast data is determined to be a commercial, the video recording and playback device  122  is programmed to exit the record mode and return to the location in the recording medium where the video signal had dropped to the black level. The video recording and playback device  122  is programmed to return to record mode after the video signal has dropped to the black level a second time. The video recording and playback device  122  records the broadcast data until the data manager  440  is able to determine whether the broadcast data broadcasted after the video signal has dropped to the black level the second time is a commercial or program data. Similarly, if the broadcast data is determined to be program data, the video recording and playback device  122  is programmed to continue recording the broadcast data. If the broadcast data is determined to be a commercial, the video recording and playback device  122  is programmed to exit the record mode and return to the location in the recording medium where the video signal had dropped to the black level the second time. 
     According to an embodiment of the present invention, the broadcast data receiver  320  (shown in FIG. 3) also operates to read digital broadcast data from digital broadcast data sources and selects a stream of digital broadcast data from the digital broadcast data source that a viewer wishes to view. For example, if the digital broadcast data source provides a plurality of streams of digital broadcast data including broadcast data with commercials, broadcast data without commercials, broadcast data with high definition, and broadcast data with low definition, the broadcast data receiver  320  operates as a switch to direct the stream of broadcast data that the viewer selects to a display device or television monitor. According to this embodiment, the selection made by the viewer may be recorded in the log  311  in the transaction processor  310  and forwarded to an external computer system via external interface  312 . 
     FIG. 5 illustrates an example of a graphical user interface according to an embodiment of the present invention. The graphical user interface  500  is generated by the transaction processor  310  (shown in FIG. 3) and may be displayed to a user via the television/monitor  121  (shown in FIG.  1 ). The graphical user interface  500  includes an entertainment category display  510  that lists the categories of entertainment system data that may be displayed by the graphical user interface  500 . The graphical user interface shown in FIG. 5 is configured to display broadcast data selections corresponding to the user&#39;s pre-set favorite television channels. The graphical user interface  500  includes a selection listing area  522  that displays the names of broadcast data selections that are broadcasted, a time heading  520  that displays the times that broadcast selections are broadcast, and a source heading  521  that displays the source of the broadcast data selections in a grid format. The graphical user interface  500  also includes scroll bars  511  and  512  and a day of the week selection bar  513  that allows a user to browse other broadcast data selections. 
     According to an embodiment of the present invention, sections of the selection listing area  522  corresponding to an broadcast data selection may be selected by a user. When selected, the transaction processor  310  (shown in FIG. 3) generates a second graphical user interface shown in FIG.  6 . The graphical user interface  600  includes a first user-selectable interface  610  that allows a user to record the broadcast data selection at the time it is broadcasted in its entirety. The graphical user interface  600  also includes a second user-selectable interface  620  that allows a user to record the broadcast data selection at the time it is broadcasted without commercials. Upon selecting one of the first or second user-selectable interfaces, the transaction processor  310  records the request in a log  311  (shown in FIG. 3) and forwards the request to the broadcast data analyzer  330  (shown in FIG.  3 ). 
     FIG. 7 illustrates a method for managing recording of broadcast data according to an embodiment of the present invention. According to one embodiment of the present invention, the method illustrated in FIG. 7 is used when broadcasted data is recorded in real-time without a delay unit. At step  701 , the broadcast data is recorded on a recordable medium. 
     At step  702 , it is determined whether a commercial or a program is being broadcasted in the broadcast data. If a commercial is being broadcasted in the broadcast data, control proceeds to step  703 . If a program is being broadcasted in the broadcast data, control returns to step  702 . According to one embodiment of the present invention, determining whether the broadcast data is a commercial or a program is achieved by reading a vertical blanking interval of the broadcast data for a message indicating whether the broadcast data is a commercial or a program. According to a second embodiment of the present invention, determining whether the broadcast data is a commercial or a program comprises monitoring an amplitude of an audio signal of the broadcast data for an increase in volume level and monitoring an amplitude of a video signal of the broadcast data for a drop of the video signal to a black level. 
     At step  703 , the recording is stopped. 
     At step  704 , the recording is resumed at a location on the recordable medium where a previously recorded video signal in the broadcast data dropped to a black level after a next video signal in the broadcast data drops to the black level. 
     FIG. 8 is a flow chart illustrating a method for managing recording of broadcast data according to a second embodiment of the present invention. According to an embodiment of the present invention, the method illustrated in FIG. 8 is used when broadcast data is recorded with a delay unit. At step  801 , a program is recorded from the broadcast data. 
     At step  802 , the broadcast data is monitored for a commercial indicator. If a commercial indicator is found, control proceeds to step  803 . If a commercial indicator is not found, control returns to step  802 . According to one embodiment of the present invention monitoring the broadcast data for the commercial indicator comprises reading a vertical blanking interval of the broadcast data for a message indicating that a commercial will be broadcasted. According to a second embodiment of the present invention, monitoring the broadcast data for the commercial indicator comprises monitoring an amplitude of an audio signal of the broadcast data for an increase in volume level and monitoring an amplitude of a video signal of the broadcast data for a drop of the video signal to a black level. 
     At step  803 , the recording is stopped. 
     At step  804 , the broadcast data is monitored for a program indicator. If a program indicator is found, control proceeds to step  805 . If a program indicator is not found, control returns to step  804 . According to one embodiment of the present invention monitoring the broadcast data for the program indicator comprises reading a vertical blanking interval of the broadcast data for a message indicating that a program will be broadcasted. According to a second embodiment of the present invention, monitoring the broadcast data for the program indicator comprises monitoring an amplitude of an audio signal of the broadcast data for a decrease in volume level and monitoring an amplitude of a video signal of the broadcast data for a drop of the video signal to a black level. 
     At step  805 , the recording is resumed. 
     In the foregoing specification, the invention has been described with references to specific embodiments thereof. It will however be evident that various modifications and changes may be made thereto without departing from the broader spirit and scope of the invention. The specification and drawings are, accordingly, to be regarded in an illustrative rather than restrictive sense.