JPH04301285A - Video tape recorder - Google Patents

Abstract

PURPOSE:To provide a video tape recorder which can quickly and surely access plural bits of information recorded in plural cassette tapes. CONSTITUTION:A car code reader 10, a microcomputer 11 storing index information and tape position information concerning recording information in SRAM 15, a control head 8 recording a VISS signal, a means reading stored information from SRAM 15 by the microcomputer 11 based on cassette identificating information and displaying it in a monitor 18 through OSD 16 and a video signal processing circuit 17, a key input device 14 selecting a desired program displayed in the monitor and a tape driving circuit 13 controlled by the microcomputer 11 executing selection program serching are provided.

Description

[Detailed description of the invention]

0001

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a video tape recorder having a function of searching information recorded on a magnetic tape.

0002

[Prior Art] Conventionally, VTR (video tape recorder)
As a first means for retrieving information recorded on a magnetic tape, there is a method of recording a cue signal by modulating the duty ratio of a servo control signal at the beginning of the information desired to be retrieved from the magnetic tape. VIS of the VHS (registered trademark) standard, which is the mainstream of so-called home 1/2-inch VTRs.
This is called the S search function, and the cue signal (VI
SS signal) and shifts to a stop state or a playback state. The second method is a counter search function that uses a linear time counter function to display the count value of the servo control signal. If it does, it will stop or move to the playback state.

0003

[Problem to be Solved by the Invention] When searching for information recorded on a magnetic tape using the above methods, firstly, the current absolute position of the magnetic tape is unknown, so it is necessary to There is a problem in that the magnetic tape must be rewound to the beginning, making it difficult to quickly obtain the information desired. Secondly, in order not to forget what has been recorded on the magnetic tape, index information such as the title and, in the case of the counter search function, the count value should be memorized, or written on a label etc. and stored on the magnetic tape. It is necessary to attach it to the cassette that is in use. Furthermore, for the reasons mentioned above, in order to avoid forgetting or erroneously erasing recorded information, only one piece of information is often recorded on one tape, reducing the efficiency of tape use.

0004

[Means for Solving the Problems] In order to solve the above-mentioned problems, the VTR of the present invention has a function of writing/reading a cue signal to/from a magnetic tape to cue the information recorded on the magnetic tape. , a cassette identification means for identifying an inserted cassette; an information acquisition means for inputting or collecting index information regarding information to be recorded; and a remaining amount detection means for detecting remaining amount information of the magnetic tape stored in the cassette. , a memory means for storing information from the cassette identification storage, the information acquisition means, and the remaining amount detection means; a writing means for writing the information into the memory means at the time of starting or ending recording; and the cassette identification. reading means for reading index information and tape remaining amount information from the memory means based on cassette identification information from the means; signal processing means for converting the index information read by the reading means into a video signal and outputting it to a monitor; program selection means for selecting information to be reproduced from index information displayed on the monitor; tape remaining amount information corresponding to the information selected by the program selection means; and current tape remaining amount detected by the remaining amount detection means. a program search means for comparing information and performing fast forward/rewind cueing based on the result; and a program searching means for reproducing recorded information on the magnetic tape when the cueing signal is detected by the program searching means. The apparatus includes a reproducing means for outputting the monitor output.

[0005]

[Operation] With the above configuration, the present invention identifies the cassette at the time of recording, stores index information and program recording position information in the memory means, records the cue signal of each program on the tape, and at the time of playback, the cassette is identified. When the desired program is selected by reading out the corresponding index information from the memory means and displaying it on the monitor, the beginning of the selected desired program is determined based on the position information stored in the memory means and the tape position information of the inserted cassette. and play it.

[0006]

Embodiments Hereinafter, embodiments of the present invention will be described with reference to the drawings. FIG. 1 is a block diagram showing the configuration of an embodiment of a VTR of the present invention, in which a cassette 1 for storing a magnetic tape 2 and a rotary head (not shown) for recording and reproducing information on the magnetic tape 2 are attached. a rotating drum 3,
A supply side reel (hereinafter referred to as S reel) 4 that sends out the magnetic tape 2 during playback or fast forwarding, and a winding side reel 5 (hereinafter referred to as T reel) that winds the magnetic tape 2 during playback or fast forwarding, A supply side reel rotation speed detector (hereinafter referred to as the S reel rotation speed detector) 6 detects the rotation speed of the S reel 4, and a take-up side reel rotation speed detector (hereinafter referred to as the S reel rotation speed detector) detects the rotation speed of the T reel 5. , a T-reel rotation speed detector) 7, a control head 8 for recording and reproducing control signals for the servo, a barcode 9 for recognizing the cassette 1, and a barcode reader 10 for reading the barcode 9. , a control signal recording and reproducing circuit 12 that writes and reads cue signals to and from the magnetic tape 2 via the control head 8, and a VTR FF/R.
A tape drive circuit 13 for driving a capstan motor (not shown) or a reel motor (not shown) to transport the magnetic tape 2 according to the EW state, playback state, etc., and a timer reservation and VTR operation. Key input device 1 such as
4, and a static random access memory (static random access memory) that stores index information and tape remaining amount information regarding the information to be recorded together with the barcode information detected by the barcode reader 10 during information recording, and is backed up by a battery (not shown) in the event of a power outage. (hereinafter referred to as SRAM)15
, an on-screen display circuit (hereinafter referred to as OSD) 16 for displaying index information stored in the SRAM 15 when necessary, and a video signal processing circuit 1.
7, a monitor 18, and a microcomputer 11 that controls the above system.

The operation of the VTR having the above-mentioned components will be explained below. FIG. 2 is a perspective view showing the state in which the cassette 1 is inserted into the VTR main body 20. When the magnetic tape 2, that is, the cassette 1 is inserted into the VTR, the bar code 9 marked on the side of the cassette 1 is converted into a bar code. By reading with the reader 10, the microcomputer 11 first recognizes which cassette has been inserted. In other words, since the cassette 1 is marked with a barcode 9 that encodes a cassette number, the cassette can be identified by decoding the barcode.

At the time of recording, the microcomputer 11 sends the cassette number, index information regarding the information to be recorded, and remaining tape amount information at the start of recording to the SRA.
Store it in M15. The index information is information that allows the contents of stored information such as recording date, recording start time, tuner channel number, and title to be recognized later. The remaining tape information is used to remember where on the tape the information to be recorded is recorded, and can be obtained, for example, by measuring the rotation period of the S reel 4 and the rotation period of the T reel 5. , for example, the remaining amount of time on the tape from the recording start position to the end of the tape.

FIG. 3 is an enlarged view of the cassette 1 in FIG. 1, and one embodiment of the method for detecting the remaining tape amount by the microcomputer 11 will be explained using this drawing. In FIG. 3, Vt is the running speed of the magnetic tape 2 [m/s]
, r is the hub radius of S reel 4 and T reel 5 [m],
Rs and Rt are the radius [m] to the outer periphery of the magnetic tape wound on the S reel and T reel, respectively, and Ss and St include the magnetic tape 2 and the reel hub wound on the S reel 4 and T reel 5, respectively. The area [m2], ωs and ωt are the rotational speeds [rad/s] of the S reel 4 and the T reel 5, respectively.

The angular velocities ωs and ωt can be obtained by measuring the period of the rotational speed detection signal detected by the S reel rotational speed detector 6 and the T reel rotational speed detector 7. Therefore, S reel 4 and T reel 5
The radii Rs and Rt to the outer periphery of the magnetic tape wound around are Rs=Vt/ωs and Rt=Vt/ωt. Therefore, the total area S of the tape including the reel hub, which corresponds to the length of the magnetic tape 2 wound around this cassette 1, is S=
Ss+St=π(Rs2+Rt2). by the way,
There are several lengths of the magnetic tape 2 wound around the cassette 1. For example, in the VHS standard mentioned above, there are 120 minute tapes, 90 minute tapes, 60 minute tapes, 30 minute tapes, etc. Therefore, by calculating the total tape area S120, S90, S60, and S30 for each tape in advance, it is possible to detect how many tapes the cassette 1 currently inserted in the VTR has. Based on the results, the tape area Sso including the reel hub on the S reel side is determined again. For example, if the detection result is a 120-minute tape, Sso is Sso=S120×ωt2/(ωs2+ωt2). Then, by dividing the net tape area excluding the area of the reel hub by the tape thickness τ [m], the remaining tape amount L [m] is calculated.
] is divided by the tape speed to find the remaining time T[
s] can be calculated. That is, L=(Sso−πr2)/
Tape remaining amount information is obtained by calculating τ, T=L/Vt.

Furthermore, the microcomputer 11 transmits the control signal recording/reproducing circuit 1 of FIG. 1 at the start of recording.
2, a cue signal, so-called VISS signal, obtained by duty ratio modulating the control signal is recorded on the magnetic tape 2.

FIG. 4 shows recording waveforms and reproduced waveforms of control signals and recording formats of cueing signals to explain the VISS search function that cues up by modulating the duty ratio of the control signal. When one cycle of is taken as 100%, a signal with a high level period of approximately 60% (Figure 4 (A) is a "0" pulse and a signal with a high level period of approximately 27.5% (Figure 4 (B))
is set as a "1" pulse, and a cue code as shown in FIG. 4(C) is recorded at the start of recording, that is, at the beginning of the program to be recorded. And when searching VISS,
This cueing code is detected by measuring the duty ratio of the reproduction control signal during fast forwarding or rewinding, and a transition is made to the reproduction mode.

The above operations are performed for each series of recording operations, that is, for each program (hereinafter referred to as a program), the cassette number, index information, and remaining tape information are stored in the SRAM 15, and a cue signal is sent. Record on magnetic tape 2. Of course, if another cassette is inserted, the cassette number corresponding to the barcode marked on that cassette will be stored.

FIG. 5 is a map diagram of the cassette number, index information, and tape remaining amount information stored in the SRAM 15, with the horizontal axis representing the lower address (4 bits) and the vertical axis representing the upper address (7 bits). expresses that space. As shown at 151, 152, and 153 in FIG. 5, for each program recorded on the tape, 1 byte for the cassette number, 1 byte for the channel, 3 bytes for the recording date, 2 bytes for the recording start time, 2 bytes are used for the recording end time, 2 bytes are used for the remaining time at the start of recording, and 5 bytes are used for the title, etc., for a total of 16 per program.
Consists of bytes. In the case of FIG. 5, the total memory capacity is 16K (16384) bits, and it is possible to store up to 128 programs.

By the way, VTR recording can be roughly divided into normal recording and timer recording, but in the case of timer recording in particular, the timer microcomputer ( The index information stored in the microcomputer 1 (not shown) is
1 receives the data and writes it into the SRAM 15. In other words, this is to prevent malfunctions when timer reservations are made but are not recorded for some reason.

The case of reproducing the tape recorded as described above will be explained below. First, when the cassette 1 is inserted into the VTR, the barcode reader 10 reads the barcode 9 written on the side of the cassette 1 in the same way as when recording, and the microcomputer 11 first confirms which cassette has been inserted. . Then, the index information corresponding to the detected cassette number is read out from the SRAM 15 and sent to the video signal processing circuit 1 via the OSD circuit 16.
7 to display it on the monitor 18 screen. FIG. 6 shows an example of the display. In this case, the cassette number inserted into the VTR is "5", and a total of five programs are currently recorded on this tape. For example, program number 1 The program with program number 2 is a 6-channel Western movie theater recorded at 9 pm on October 20th, and the program with program number 2 is a 10-channel drama recorded at 7 pm on October 25th. After selecting the program number on the monitor 18 screen using the operation key 14, V
When TR is set to playback mode, microcomputer 11
After locating the selected program using a software program built into the system, the system automatically enters a playback state. In addition, if cassette 1 is not inserted or if you want to search for the contents of a cassette other than the one inserted, inputting the cassette identification information from the outside using the key input device 14 etc. will correspond to the cassette identification information. The selected index information is displayed on the monitor screen in the same way as in FIG. It enters the playback state. The above operation will be explained with reference to the flowchart of the software program installed in the microcomputer 11 shown in FIG.

First, in processing block 111,
The remaining amount of tape is detected in the same way as described for recording, and the current tape position is detected. Next branch 112
Detected when recording a program selected in SRAM15
Remaining tape time and processing block 111 stored in
Compare the current tape remaining time detected with
As a result, if the current position is 10 minutes or more before the target position, the process moves to processing block 113 and the VTR is put into a fast forward (FF) state, so that the current position is 10 minutes or more before the target position.
If it is more than 1 minute later, the process moves to processing block 114 and the VTR
are in the rewind (REW) state, and each processing block 1
Return to 11. Further, if the current position is within 10 minutes from the target position, the process moves to processing block 115 and the VTR is placed in the VISS search state described above, and when the cue code of the selected program is detected, the VTR is placed in the playback mode in processing block 116. Complete a series of search operations. In other words, the recorded position of the program is roughly detected by the tape remaining amount detection function, and finally detected with high precision by the VISS search function.

As described above, according to the video tape recorder of the embodiment of the present invention, the cassette is identified by the bar code at the time of recording, and index information such as the cassette number, date, time, channel title, etc., and each program record are recorded. Store position information in SRAM and display VIS at the beginning of each program on the tape.
The S signal is recorded, and during playback, the cassette is identified by the barcode and the corresponding index information is sent to the SRA.
Read from M and display on the monitor. When you enter the desired playback program number from the key input device, the current position of the tape will be set to SR.
It is compared with the start position of the desired program stored in AM, and
The head position is roughly moved to the vicinity of the playback start position by the F or REW operation, and the VISS search is arranged so that the desired program is selected accurately. By inputting a key, the desired program can be automatically and quickly played back.

When over-recording is performed on an already recorded tape, the microcomputer 11 determines the remaining tape time and end of recording of the program to be over-recorded among all the programs registered with that cassette number. By erasing from the SRAM 15 all the index information and tape remaining information of programs that have a remaining tape time between the remaining tape times of
It is possible to improve the usage efficiency of

Furthermore, VTRs generally have a plurality of recording time modes, but no matter what recording time mode the above-mentioned tape remaining amount detection time is, it is converted into a long-time recording mode to prevent search malfunctions. be able to.

[0021] Also, during or after recording, the SRAM1
By inputting the audio switching data in the index information on 5, it is possible to automatically play back with the desired audio during playback. If you specify audio (Japanese) playback, the playback will automatically be in Japanese.

[0022] Furthermore, when searching for and reproducing a program as described above, a replayed flag is set in the index information on the SRAM 15 corresponding to the program, and when displaying the recorded program as shown in FIG. By displaying a mark (not shown), unplayed programs can be seen at a glance when the same cassette is inserted later, and it is possible to easily prevent recorded programs from being forgotten or deleted by mistake. be.

[0023] Also, during or after recording, the SRAM1
By setting the playback prohibition flag set in the index information in 5 above and also inputting a password at the same time, the program search operation described above is prohibited, and by inputting the password, it is possible to search for a program. It is also possible to protect recorded programs.

[0024] Furthermore, it is also possible to easily realize program playback in which a plurality of program numbers are selected during program selection during playback, and programs are played back in series.

In addition, since the total recording time of all programs recorded on a certain tape can be calculated from the data stored in the SRAM 15, the remaining recordable time can be calculated based on the tape type determination result of detecting the remaining tape amount before starting the next recording. It is also possible to display it on the monitor screen.

[0026]

As is clear from the above embodiments, according to the present invention, access problems, which were the biggest problem with conventional VTRs, can be solved in managing and searching a plurality of pieces of information recorded on a plurality of cassette tapes. In addition to improving the shortcomings, it is also possible to improve the efficiency of using magnetic tape, and it is also possible to display the remaining recordable time of recorded cassette tapes and provide protection functions such as prohibiting playback of recorded information. A video tape recorder that can also be realized can be provided.

[Brief explanation of drawings]

FIG. 1 is a block diagram showing the configuration of a video tape recorder according to an embodiment of the present invention.

[Fig. 2] A perspective view showing a state in which a cassette is inserted into the VTR body of the same embodiment.

[Figure 3] Enlarged view of the cassette part of the same example

[Fig. 4] Recording format diagram of control signal recording waveforms, reproduction waveforms, and cueing signals to explain the VISS search function of the same embodiment.

[Figure 5] Map diagram of cassette number, index information, and remaining tape amount information stored in the SRAM of the same embodiment

[Figure 6] Schematic diagram of a monitor screen display example of the same embodiment

[Figure 7]
Flowchart of the software program built into the microcomputer of the same example

[Explanation of symbols]

1 Cassette 2 Magnetic tape 4 Supply reel 5 Take-up reel 6 Supply reel rotation speed detector 7 Take-up reel rotation speed detector 8 Control head 9 Barcode 10 Barcode reader 11 Microcomputer 12 Control signal recording/reproducing circuit 13 Tape drive circuit 14 Key input device 15 SRAM 16 On-screen display circuit 17 Video signal processing circuit 18 Monitor

Claims (7)

[Claims] 1. A video tape recorder having a function of writing/reading a cue signal to/from a magnetic tape to cue information recorded on the magnetic tape, the video tape recorder having a cassette identification means for identifying an inserted cassette. an information acquisition means for inputting or collecting index information regarding information to be recorded; a remaining amount detection means for detecting remaining amount information of the magnetic tape stored in the cassette; the cassette identification means; and the information acquisition means. and a memory means for storing information from the remaining amount detecting means, a writing means for writing each piece of information into the memory means at the time of starting or ending recording, and a memory means for storing information from the remaining amount detecting means, and a writing means for writing the information into the memory means at the time of starting or ending recording, reading means for reading the index information and the tape remaining amount information from the memory means; signal processing means for converting the index information read by the reading means into a video signal and outputting it to a monitor; and an index displayed on the monitor. A program selection means for selecting information to be reproduced from the information, and comparing the remaining tape amount information corresponding to the information selected by the selected program selection means with the current tape remaining amount information detected by the remaining amount detection means, and comparing the result. a program search means for fast-forwarding/rewinding the magnetic tape based on the cue signal; and a program search means for reproducing recorded information on the magnetic tape and displaying it on the monitor when the program search means detects the cue signal. A video tape recorder comprising a playback means for outputting. 2. The cassette identification information matches the cassette identification information already stored in the memory means, and the recording position on the magnetic tape that can be detected by tape remaining amount information and index information is already stored in the memory means. 2. The video tape recorder according to claim 1, wherein when recording positions detected by tape remaining amount information and index information overlap, said information is erased from said memory means. 3. When a plurality of recording time modes are provided, all of the remaining tape information is stored in the memory means and processed by each of the program means based on information converted to a long time mode. 1. The videotape recorder described in 1. 4. The video tape recorder according to claim 1, wherein the audio switching information is added to the index information when writing into the memory means. 5. The video recording medium according to claim 1, wherein when the recorded information on the magnetic tape is reproduced by the program selection means and the program search means, the reproduced information is added to the index information stored in the memory means. Tape recorder. 6. The video tape recorder according to claim 1, wherein the reproduction prohibition information and the password are added to the index information when writing into the memory means. 7. An unrecorded storage device that calculates the total recording time using tape remaining amount information and index information having the same cassette identification information, and calculates remaining recordable time information using the tape type discrimination result from the remaining amount detecting means. 2. The video tape recorder according to claim 1, further comprising recording time detection means and signal processing means for outputting recordable time information on a monitor.