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`Europaisches Patentamt
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`European Patent Office
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`Office european des brevets
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`111111111111111111111111111111111111111111111111111111111111111111111111111
`EP 0 762 756 81
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`(11)
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`EUROPEAN PATENT SPECIFICATION
`
`(45) Date of publication and mention
`of the grant of the patent:
`06.03.2002 Bulletin 2002/10
`
`(21) Application number: 96113735.3
`
`(22) Date of filing: 28.08.1996
`
`(51) lnt Cl.7: H04N 5n75
`
`(54) Video signal recording and reproducing apparatus
`Fernsehsignalaufnahme- und -wiedergabeanlage
`Appareil d'enregistrement et de reproduction de signal video
`
`(84) Designated Contracting States:
`DE FR GB NL
`
`(30) Priority: 11.09.1995 JP 23218395
`
`(43) Date of publication of application:
`12.03.1997 Bulletin 1.997/11
`
`(60) Divisional application:
`01118761.4/1161089
`
`(73) Proprietor: MATSUSHITA ELECTRIC INDUSTRIAL
`CO., LTD.
`Kadoma-shi, Osaka 571-8501 (JP)
`
`(72) Inventors:
`• Sasaki, Seishl
`Kobe-shl, Hyogo-ken (JP)
`• Katou, Yoshlkazu
`Katano-shl, Osaka (JP)
`
`(74) Representative: Kugele, Bernhard et al
`Novagraaf SA 25, Avenue du Pallly
`1220 Les Avanchets- Geneva (CH)
`
`(56) References cited:
`US-A· 5 237 426
`US-A- 5 329 320
`
`US-A· 5 241 428
`us-A- 5 438 423
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`,...
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`Note: Within nine months from the publication of the mention of the grant of the European patent, any person may give
`notice to the European Patent Office of opposition to the European patent granted. Notice of opposition shall be filed in
`a written reasoned statement. It shall not be deemed to have been filed until the opposition fee has been paid. (Art.
`99(1) European Patent Convention).
`
`Pt1nted by Jouve, 75001 PARIS (FR)
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`Description
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`1. Field of the Invention:
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`[0001] The present invention relates to a video signal recording and reproducing apparatus which can simultaneously
`record and reproduce a video by using a disk apparatus.
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`2. Description of the Related Art:
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`[0002] A video tape recorder (VTR) has heretofore been used as a home-use video recording apparatus. As is well
`known, a VTR receives a broadcast program transmitted by a broadcasting station via an antenna, records the program
`and then reproduces the program. That is to say, having once finished the recording operation of a predetermined
`program, the VTR rewinds the tape on which the program has been recorded and then reproduces the received and
`recorded program to be watched.
`[0003) A currently available VTR cannot record and reproduce a video simultaneously. For example, assuming that
`a broadcast program which starts at 1 0 o'clock and ends at 12 o'clock is now being received and recorded by a single
`VTR, it is impossible to reproduce and watch the broadcast program from the beginning from 11 o'clock on, while
`continuing receiving and recording the program. It is much less impossible to perform a trick play reproducing operation
`(e.g., a fast-forward reproducing operation or a backward reproducing operation) of a recorded video of a program
`which is now being received and recorded. On the other hand, a technique which is called "following reproducing
`operation" is currently utilized for a live broadcast relayed by a broadcasting station. In accordance with this technique,
`a video which has been transmitted to a broadcasting station is slightly delayed and then delivered substantially in real
`time. However, in such a case, it is necessary to use either a plurality of VTRs or an optical disk apparatus of a special
`type in which a recording head and a reproducing head are separately provided, for simultaneously performing the
`recording and the reproducing operations. If a plurality of VTRs are simultaneously used, then it becomes adversely
`complicated tc, operate these apparatuses. On the other hand, the use of such an optical disk apparatus of a special
`type disadvantageously increases the costs.
`[0004] The document US-A-5 438 423 also discloses a video recording and reproducing apparatus which allows to
`reproduce a recorded video at a later -time and at a desired rate. A video signal is continuously written into a random
`access dynamic buffer, such as an optical disk, in a recirculating manner, and may be read out on a random access
`basis.
`
`SUMMARY OF THE INVENTION
`
`[0005) Thus, the present invention concerns a video signal recording and reproducing apparatus as defined in the
`appended claims.
`[0006] By utilizing the above-described configurations, it is possible to provide an apparatus which can independently
`perform a trick play reproducing operation (e.g., a fast-forward reproducing operation or a backward reproducing op(cid:173)
`eration) of a recorded part of a broadcast program which is now being received, while compression encoding and
`recording the broadcast program. As a result, it is possible to start watching a recorded part of a program without
`waiting for the program to end as is done in the recording and reproducing operations performed by a conventional
`single VTR. In addition, even when a viewer initially starts watching a program at a time much later than the broadcast
`start time of the program, the viewer can finish watching the program substantially at the same time as the broadcast
`end time by additionally utilizing a fast-forward reproducing function in the middle of the reproducing operation.
`[0007] According to the present invention, it is possible to provide an apparatus which can perform a normal repro(cid:173)
`ducing operation or a trick play reproducing operation (e.g., a fast-forward reproducing operation or a backward repro(cid:173)
`ducing operation) of a recorded part of a broadcast program which is now being received, while recording the broadcast
`program by using a universal hard disk apparatus without using a plurality of VTRs or an expensive optical disk appa(cid:173)
`ratus for which a recording head and a reproducing head are separately provided. As a result, it is possible to start
`watching a recorded part of a program without waiting for the program to end, as is necessary in the recording and
`reproducing operations performed by a conventional single VTR. In addition, even when a viewer initially starts watching
`a program at a time much later than the broadcast start time of the program, the viewer can finish watching the program
`substantially at the same time as the broadcast end time by additionally utilizing a fast-forward reproducing function
`in the middle of the reproducing operation, so that a considerable amount of time can be saved. Moreover, in the case
`where a viewer cannot help stopping watching a program in the middle of the program, even if the program still continues
`when the viewer resumes watching the program, the viewer can reproduce and watch the program from the scene
`which was broadcast when the viewer left, while continuing recording the program. Furthermore, in the case where a
`viewer watches a first program while recording a second program on a different channel, it is possible to instantaneously
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`start watching the second program from the beginning thereof at a time after the first program ends and before the
`second program ends.
`[0008) Thus, the invention described herein makes possible the advantage of providing a video signal recording and
`reproducing apparatus which can simultaneously record and reproduce a television signal.
`[0009] This and other advantages of the present invention will become apparent to those skilled in the art upon
`reading and understanding the following detailed description with reference to the accompanying figures.
`
`BRIEF DESCRIPTION OF THE DRAWINGS
`
`[0010] Figure 1 is a block diagram illustrating a configuration for a video signal recording and reproducing apparatus
`in a first example of the present invention.
`[0011] Figure 2 is a diagram illustrating an operational concept in the first example.
`[0012] Figure 3 is a diagram illustrating the contents of a table RAM.
`[0013] Figure 4 is a detailed timing chart of peripheral hardware for a hard disk apparatus.
`[0014] Figure 5 is a block diagram illustrating a configuration for a video signal recording and reproducing apparatus
`in a fourth example of the present invention.
`[0015] Figure 6 is a block diagram illustrating a configuration for a video signal recording and reproducing apparatus
`in a sixth example of the present invention.
`[0016] Figure 7 is a diagram illustrating a screen synthesis in the sixth example of the present invention.
`[0017] Figure 8 is a diagram illustrating a screen separation in the sixth example of the present invention.
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`DESCRIPTION OF THE PREFERRED EMBODIMENTS
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`[0018) Hereinafter, the embodiments of the present invention will be described with reference to the accompanying
`drawings.
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`Example 1
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`[0019] Figure 1 is a block diagram illustrating a configuration for a video signal recording and reproducing apparatus
`in a first example of the present invention. In Figure 1, the reference numeral1 denotes an antenna; 2 denotes a tuner;
`3 denotes a demodulator; 4 denotes an MPEG1 encoder; 5 and 6 denote recording buffer memories; 7 denotes a first
`switch; 8 denotes a hard disk apparatus; 9 and 10 denote reproducing buffer memories; 11 denotes a second switch;
`12 denotes an MPEG1 decoder; 13 denotes a TV monitor; 14 denotes a hard disk controller; 15 denotes a table RAM;
`16 denotes a system controller; 17 denotes a timer; and 18 denotes an operator panel.
`[0020] First, before describing the operation of the apparatus in the first example with reference to Figure 1, the
`operational concepts will be described with reference to Figure 2. In this example, it is assumed that a viewer wants
`to watch a program which is to be broadcast from 10 p.m. to 12 p.m. (as shown in portion (a) of Figure 2) but that it is
`only after 11 p.m. that the viewer can watch the program because of some inconvenience.ln such a case, in accordance
`with the method of this example, while recording the program from 10 p.m. to 12 p.m. (as shown in portion (b) of Figure
`2), the viewer can start reproducing the program from the beginning thereof from 11 p.m. (as shown in portion (c) of
`Figure 2). When a normal reproducing mode is selected, the reproducing operation ends at 1 a.m. which is two hours
`later than the time when the viewer started watching the program. On the other hand, since a fast-forward reproducing
`operation can also be performed on a part of the program which has already been recorded as shown in portion (d)
`of Figure 2, it is also possible to reproduce all of the program at a time slightly later than 12 p.m., that is the time when
`the broadcasting of the program actually ends.
`[0021] Hereinafter, a detailed operation of the video signal recording and reproducing apparatus of the first example
`will be described with reference to Figure 1. First, a viewer pre-sets a TV channel, a recording start time and a recording
`end time of a program to be watched on the operator panel18. For example, it is assumed that the viewer sets a
`program on channel# 6 starting at 10 p.m. In such a case, when it is 10 p.m., the system controller 16 sets the tuner
`2 to channel# 6 in accordance with the information supplied from the timer 17 such that the electric waves for the
`channel # 6 are selected from the electric waves received by the antenna 1, and the demodulator 3 demodulates the
`received waves into signals.
`[0022) The received signals can be monitored on the TV monitor 13. The received signals are converted by the
`MPEG1 encoder 4 into compressed video signals so as to be bit streams having a bit rate of 1.5 Mbps. These signals
`are transmitted via the first and the second recording buffer memories 5 and 6 having a capacity of 200 Kbytes, for
`example, and the first switch 7 so as to be written onto the hard disk apparatus 8.
`[0023] This operation will be described in detail later with reference to Figure 3. The sector information indicating
`the physical positions of the compressed video signals written on the hard disk and the time information of the written
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`signals are stored in the table RAM 15 so as to correspond to each other. Such a state is maintained until 11 p.m.,
`when the viewer starts watching the program. When it is 11 p.m., the viewer starts watching the program on the TV
`monitor 13. In this case, if the viewer wants to watch the program starting at 10 p.m. (i.e., reserved recording start
`time) from the beginning thereof, then the viewer has only to push the reproducing button (not shown) on the operator
`panel18.
`In this case, the program starting at 10 p.m. is reproduced from the beginning thereof from 11 p.m. at a normal
`[0024]
`reproducing speed as shown in portion (c) of Figure 2. The hard disk controller 14 controls the hard disk apparatus 8
`in accordance with the information supplied from the table RAM 15, so that the compressed video signals recorded on
`the hard disk apparatus 8 are reproduced via the reproducing buffer memories 9 and 10 and the second switch 11.
`This operation will be described in detail later with reference to Figure 3. The reproduced compressed video signals
`are decoded by the MPEG1 decoder12 so as to be video signals which are displayed on the TV monitor 13.
`(0025]
`It is noted that, in this example, the video signals compressed by the MPEG1 encoder 4 are being transmitted
`via the recording buffer memories 5 and 6 and the first switch 7 so as to be continuously written onto the hard disk
`apparatus 8 until12 p.m. during the reproduction of the video signals. When it is 12 p.m., the system controller 16
`finishes recording the compressed video signals onto the hard disk apparatus 8 in accordance with the information
`supplied from the timer 17. In this case, it is possible to monitor on the TV monitor 13, the video signals which are
`being written in parallel with the video signals which are being reproduced by using a technique such as a screen
`division.
`[0026] On the other hand, in performing the reproducing operation, the viewer can reproduce a part of a program to
`be watched in detail at a slower speed and can reproduce an unnecessary part of the program at a higher speed in
`accordance with the instructions supplied from the system controller 16 by operating the operator panel18. The cor(cid:173)
`respondence between the sector information of the compressed video signals recorded on the hard disk, and the time
`information of the signals, has been stored in the table RAM 15 for performing these operations.
`[0027) The format of this table is shown in Figure 3. In Figure 3, the reference numeral19 denotes the time information
`represented as a time code and 20 denotes a sector number on the hard disk. In this example, since each of a plurality
`of successive sectors corresponds to one second, sector addresses are indicated every other second in Figure 3. In
`accordance with the operation of the viewer, the hard disk controller 14 reproduces required video signals based on
`this time information.
`(0028]
`In the case of the MPEG1 standard, an image is generally compressed based on a unit consisting of a plurality
`of frames. A concept "GOP (group of pictures)" is used as the unit. For example, in the case where 1 GOP= 15 frames,
`1 GOP covers a video corresponding to 0.5 second. Thus, in the case of performing a fastforward reproducing operation
`or a slow reproducing operation, if a decimation or an interpolation is performed on a GOP basis with respect to a video
`which has been decoded on a GOP basis, the resulting motion of the image is no longer smooth. In order to make the
`motion smooth, the decimation or the interpolation is required to be performed on a frame basis.
`(0029] That is to say, a 1 Ox fast-forward reproducing operation (or a fast-forward reproducing operation performed
`· at a speed ten times as high as a normal reproducing speed) is realized by reproducing one frame out of ten frames.
`On the other hand, a 1/10x slow reproducing operation is realized by displaying one and the same frame 10 times in
`succession.
`[0030] A time difference between the time when the video which is now being reproduced was recorded (hereinafter,
`such a time will be referred to as a "video recording time") and the current time, can be calculated by subtracting the
`video recording time, obtained by using the time information supplied from the table RAM 15, from the current time. If
`the time difference is displayed on the TV monitor 13, the time difference can be monitored. Before this time difference
`becomes zero, any arbitrary part of the video which has already been recorded can be reproduced. In addition, it is
`also possible to simultaneously display on the TV monitor 13 both the time corresponding to the output of the demod-
`ulator 3 and the time corresponding to the output of the MPEG1 decoder 12 by dividing the screen into two parts. Then,
`a video which is now being broadcast (and corresponds to the output of the demodulator 3) and a video which is now
`being reproduced (and corresponds to the output of the MPEG1 decoder 12) can be simultaneously watched on the
`same screen.
`[0031) Assuming that the hard disk apparatus has a capacity large enough to record compressed video signals
`corresponding to two hours, if the viewer does not start watching a program within two hours after the recording start
`time, the recorded signals are updated from the point of time two hours later than the recording start time, whereby a
`program corresponding to two hours preceding the time when the viewer starts watching the recorded program can
`always be covered. On the other hand, an update halt mode may also be selected. In such a case, a video can only
`be recorded for two hours in the same way as a commonly used VTR.
`[0032] Hereinafter, detailed timings of peripheral hardware of the hard disk apparatus 8 will be described with refer(cid:173)
`ence to Figure 4.
`[0033) The detailed configuration of the hard disk apparatus 8 is omitted in Figure 1. A hard disk apparatus which is
`universally used as a peripheral device for a computer system can be used as the hard disk apparatus 8. The hard
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`disk apparatus 8 may include either one disk medium or a plurality of disk media and includes a recording and repro(cid:173)
`ducing head, not a head exclusively used for a recording operation or a reproducing operation.
`[0034] Portion (a) of Figure 4 represents an output of the MPEG1 encoder 4 and A1, A2, A3, ... A6 indicate the
`signals obtained by dividing the output by every 1.5 Mbits. Portion (b) of Figure 4 represents the operational modes
`of the recording buffer memory 5 having a capacity of 200 Kbytes and W indicates writing a signal onto the memory
`and R indicates reading out a signal from the memory. Thus, A1-W means writing a signal A1 onto the buffer memory
`and A1·R means reading out the signal A1 from the buffer memory, for example. A signal is written onto the buffer
`memory in real time simultaneously with the video signals, while the signal is read out from the buffer memory at a
`high rate in accordance with the transfer rate at which the signal is transferred to the hard disk apparatus 8.
`[0035] Portion (c) of Figure 4 represents the operational modes of the recording buffer memory 6 having a capacity
`of 200 Kbytes and Wand R indicate the same operations as those in portion (b). The buffer memories 5 and 6 operate
`in pairs. More specifically, while one of the buffer memories 5 or 6 transfers data to the hard disk apparatus 8 via the
`first switch 7, the other buffer memory 6 or 5 stores therein a compressed video signal supplied from the MPEG1
`encoder 4.
`[0036) Portion (d) of Figure 4 represents the seek timings for writing data onto the hard disk apparatus 8. Portion
`(e) of Figure 4 represents the timings at which data is transferred from the buffer memories 5 and 6 to the hard disk
`apparatus 8 so as to be written thereon. A1·W means writing the signal A1 onto the hard disk apparatus 8. Though
`the time sequence is not specifically shown in Figure 4, portions (b) and (c) always precede portion (e). For example,
`the signal A1 read out by A1-R in portion (b) is written by A1-W in portion (e).
`[0037] Portion (f) of Figure 4 represents the seek timings for reading out data from the hard disk apparatus 8. Portion
`(g) of Figure 4 represents the timings at which data is read out from the hard disk apparatus 8 and B1·R means reading
`out a signal B1 from the hard disk apparatus 8, for example. Portion (h) of Figure 4 represents the operational modes
`of the reproducing buffer memory 9 having a capacity of 200 Kbytes and B1-W means writing the signal B1 onto the
`buffer memory 9.
`[0038] Portion (I) of Figure 4 represents the operational modes of the reproducing buffer memory 10 having a capacity
`of 200 Kbytes and W and R indicate the same operations as those described above. The buffer memories 9 and 10
`operate in pairs. More specifically, while a signal read out from the hard disk apparatus 8 is written onto one of the
`buffer memories 9 or 10, the other buffer memory 10 or 9 reads out a signal, which has been supplied from the hard
`disk apparatus 8 and stored in the buffer memory 10 or 9, at a rate of the videg signal and then supplies the signal to
`the MPEG1 decoder 12 via the second switch 11.
`[0039) Portion (j) of Figure 4 represents an input to the MPEG1 decoder 12. As shown in Figure 4, the input has
`been extended so as to have the same period as that of the output in portion (a) and is continuously reproduced.
`[0040) As shown in Figure 4, for recording and reproducing a video signal simultaneously and continuously, the
`period of each of the signals A 1, A2, A3, ... is set to be longer than the following time T:
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`T = (seek time for preparing to record data onto the hard disk}
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`+ (time required for writing the data having the
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`period onto the hard disk)
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`+ (seek time for preparing to reproduce the data from
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`the hard disk)
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`+ (time required for reading out the data having the
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`period from the hard disk)
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`If the total of these times becomes longer than the period of A1, A2, A3, ... , then the video cannot be recorded
`[0041)
`but overflows. Thus, the period is required to be sufficiently longer than the total time. Since the seek time of the hard
`disk, in particular, largely varies depending upon situations, a maximum seek time is required to be estimated and
`included in the sum.
`[0042)
`In this case, the period of A1, A2, A3, ... is a time during which an MPEG bit stream having a bit rate of 1.5
`Mbps is occupied by a buffer memory having a capacity of 200 Kbytes: 200 k + (1.5 M + 8) = about 1 second. Assuming
`that the data transfer rate of the hard disk is 1 Mbyte per second, the time required for transferring the data is: 200 k
`+ 1 M = 0.2 second. Even when the maximum seek time is estimated to be 100 milliseconds,
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`T = 0.1 + 0.2 + 0.1 + 0.2 = 0.6 second < 1 second
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`Thus, a sufficient margin time can be obtained.
`[0043] As described above, the video signal recording and reproducing apparatus according to the present invention
`is a video signal recording and reproducing apparatus using a hard disk which can simultaneously perform the recording
`and reproducing operations in different portions of the same hard disk. Thus, it is possible to provide an apparatus
`which can perform a trick play reproducing operation (e.g., a fast-forward reproducing operation or a backward repro·
`ducing operation) of a recorded part of a broadcast program which is now being recorded, while recording the broadcast
`program.
`[0044] As a result, it is possible to start watching the recorded part of a program without waiting for the program to
`end, as is necessary in the recording and reproducing operations performed by a conventional single VTR. In addition,
`even when a viewer initially starts watching a program at a time much later than the broadcast start time of the program,
`the viewer can finish watching the program substantially at the same time as the broadcast end time by additionally
`utilizing a fast-forward reproducing function in the middle of the reproducing operation, so that a considerable amount
`of time can be saved.
`[0045] Furthermore, though audio signal recording and reproducing sections are not shown in Figure 1, a sound
`accompanied with a video can be processed completely in the same way as the video. Therefore, the same description
`as applied to a "video• in this example is applicable to "video and sound".
`It is noted that it is possible to perform the writing operation onto a hard disk only when it is necessarY while
`[0046]
`a viewer watches a TV program for using the hard disk as long as possible. In such a case, a viewer starts a video
`recording operation by pushing an instruction button. A recording start button and a reproducing start button are pro·
`vided for the operator panel 18 or a single button can be used for these two purposes. This function is effectively
`applicable to a case where a viewer cannot help stopping watching a TV program in the middle of the program for
`some unavoidable reason. For example, in the case where it becomes necessary to stop watching a TV program in
`the middle for receiving a visitor, responding to a telephone call, taking a bath or having a meal or the like, the viewer
`pushes the recording start button for recording the program from that point of time, settles his business and then pushes
`the reproducing start button. Thus, the recorded program is reproduced and the viewer can watch the program from
`the point of time when he started recording the program without missing any scene of the program. In addition, by
`providing an end setting button for allowing a viewer to set a recording end time easily, even if the viewer must go out
`suddenly and does not know exactly when he will be able to come home, the viewer can record a video for as long as
`he wants. Thus, the viewer can comfortably leave after he sets the hard disk in a writing state. In this case, if the end
`setting button is configured such that the recording time can be set depending upon how many times the viewer pushes
`the button (for example, one push of the button allows the program which is now being watched to be recorded for 30
`35 minutes and two pushes of the button allows the program to be recorded for 1 hour), then the viewer can advantageously
`operate this apparatus very easily.
`[0047] Since the program is continuously recorded during the reproduction of the program, the viewer can naturally
`watch the part of the program which is being broadcast during the reproduction.
`In addition, a TV signal detector (not shown in Figure 1) for determining whether or not a TV broadcast is
`[0048]
`available or not is incorporated in the demodulator 3 shown in Figure 1. A synchronizing signal detector which is
`commonly provided for an existing TV receiver can be used as the TV signal detector and it is not necessary to addi(cid:173)
`tionally provide a novel circuit. Hereinafter, a case where a synchronizing signal detector is used as the TV signal
`detector will be specifically described.
`[0049] First, it is determined whether or not a synchronizing signal exists in the demodulated video signal. If a syn-
`chronizing signal is absent in the demodulated video signal, then it is determined to be out of a broadcasting time,
`thereby protecting the hard disk apparatus from the writing operation. If the writing operation has already been started
`on the hard disk apparatus, the writing operation onto the hard disk apparatus is temporarily suspended at a point of
`time when the synchronizing signal .is no longer detected and is resumed when the synchronizing signal is detected
`again. As a result, it is possible to avoid performing a recording operation in an undesired time period (e.g., a midnight
`time or the like when no broadcast is available), so that the lifetime of the hard disk apparatus can be lengthened. This
`function will be effective for avoiding performing an unnecessary recording operation at midnight when no broadcast
`· is televised, supposing that a hard disk comes to have a recording capacity large enough to always record a televised
`video corresponding 24 hours preceding the current time in the near future. Since a synchronizing signal detector is
`commonly available well known circuit, the detailed description thereof will be omitted herein. A synchronizing signal
`detector of the type which integrates a synchronizing signal obtained from a well known synchronizing signal separator
`thereby determining whether or not the DC level thereof is a normalized value, or a synchronizing signal detector of
`the type which determines whether or not the frequency of the synchronizing signal is a predetermined value (e.g., the
`frequency of a horizontal synchronizing signal is 15.73 KHz in an NTSC standard) is used herein.
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`[0050] This example has been described while using a synchronizing signal detector as a TV signal detector. How·
`ever, in the case where a digital broadcast is received, the TV signal can be detected by a method in which it is
`determined whether or not an error signal detected by an error signal detector, used for reproducing a clock for a PLL
`or the like, is at a predetermined level or by a method in which it is determined whether or not the amount of the error
`flag output from an error detector for correcting an error of a transmitted signal is at a predetermined level.
`[0051]
`If a viewer continuously records a program and supplies a signal by the push of a button or the like for stopping
`watching the program such that the recording stop time, the address and the like are stored; then the viewer can
`naturally reproduce the program from the point of time when the viewer stopped watching the program by pushing the
`reproducing start button for resuming watching the program.
`[0052]
`In addition, by additionally providing a second tuner and a second demodulator (though not shown in Figure
`1), a channel to be watched and a channel to be recorded can be independently designated. For example, a case
`where a second program to be watched by a viewer starts on another channel while the viewer is watching a first
`program to be recorded will be assumed. In such a case, if the viewer starts to record the second program on the
`second channel, the viewer can watch the second program from the beginning thereof from the point of time when the
`first program which the viewer is watching ends.
`
`Example 2
`
`[0053] Hereinafter, a second example of the present invention will be described. Since the fundamental configuration
`in the second example is substantially the same as that in the first example shown in Figure 1, no drawings will be
`particularly referred to for describing the second example.
`[0054] The video signal recording and reproducing apparatus of the second example is further provided with a circuit
`for inputting a video and/or a sound other than that of a broadcast (e.g., a reproduced signal of a VTR). If a part of a
`broadcast or desired video and/or sound input through the circuit is stored in the hard disk apparatus 8 for about 1 0
`seconds and is automatically reproduced at a predetermined time every morning, the broadcast or the video and/or
`the sound can be used in place of an alarm clock so that a user can wake up comfortably.
`(0055]
`It is noted that in such a case, the volume of the sound is required to be automatically adjusted to a sufficiently
`large volume, irrespective of a sound volume which was set the previous day. Furthermore, by additionally providing
`a speech recognition circuit for the apparatus shown in Figure 1, the apparatus can reproduce a predetermined video
`by recognizing the audible alarm of an alarm clock other than the clock incorporated in the system. Alternatively, by
`recognizing not an alarm but a speech pattern such as "I'm home• when a user comes home, the apparatus can
`reproduce a p