JPH03208483A - Television system conversion video tape recorder - Google Patents

Abstract

PURPOSE:To convert the TV system even when the TV system differs from a video source and a monitor TV receiver and to monitor the video signal by devising the video tape recorder such that a signal before TV system conversion and a signal after TV system conversion are both outputted to a video signal output terminal at recording. CONSTITUTION:A video signal selected by a changeover switch 4 is inputted to a TV system conversion circuit 6 at recording via a changeover switch 5 and the signal is converted into the TV system selected by a system selection switch 7 in the circuit 6. The vs at recording, that is, an output signal from the changeover switch 5 is outputted to a video signal output terminal 12 via a changeover switch 10 and the signal is monitored by a television receiver. when the TV system of the video source differs from the TV system of the monitor television receiver, the TV system conversion circuit 6 converts the system into that for the monitor television receiver and the resulting signal is monitored by the monitor television receiver connecting to the video signal output terminal 11.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of Industrial Application The present invention is applicable to NTSC. PAL. The present invention relates to a television format conversion video tape recorder having a built-in television format conversion circuit for enabling mutual conversion between various television formats such as SRCAM.

Conventional technology World television standard system (hereinafter referred to as TV system)
There are different methods adopted in different countries around the world. T
There are three main types of V system: NTSC (National Telephone System), which is used in Japan, the United States, etc.
system + committee) system, PAL (Phase Vision System + Committee) system, which is mainly adopted in Western European countries
Alternation by Line) method, SRCAM adopted in the Soviet Union, France, Eastern European countries, etc.
(Se'quentiel Couleur aM'
emoire) method. These TV systems differ in the number of fields per second (field frequency), the number of scanning lines in one field, and the color signal modulation method.

For example, in the NTSC system, the field frequency is 59
．． 94Hz, the number of scanning lines is 525, and the color signal has a subcarrier frequency of 3. In contrast, in the PAL system, the field frequency is 50 Hz, the number of scanning lines is 625, and the subcarrier frequency of the color signal is 4.5 MHz. 43361875MHz
The color signal is also modulated by inverting the polarity of one of the color difference signals for each line.

As mentioned above, since each TV system is different, TV receivers and video tape recorders (hereinafter referred to as VTRs) are also compatible with each TV system.

Therefore, it is possible to play video tapes recorded in countries with different TV formats (hereinafter referred to as different format video tapes),
In order to create a different format videotape, a TV standard format converter (hereinafter referred to as a TV format converter) is required.

A conventional example of a case where a TV format conversion device is used will be described with reference to the drawings.

FIG. 3 is a connection diagram when playing a different format videotape. In FIG. 3, first, the different format videotape 21
In order to display a videotape recorded in the PAL system (for example, a videotape recorded in the PAL system) on an NTSC system TV receiver 22 in Japan, first a VT that can play back the different format videotape 2l is required.
R23 is required. This corresponds to each TV system,
This is because the servo system that controls the tape speed of the VTR and the rotational speed and phase of the rotary head and the reproduction signal processing system that reproduces the video signal recorded on the video tape are different. If the different format videotape 2l is a recording tape of the PAL format, a VTR 23 capable of reproducing the PAL format is required. Next, the reproduced output signal of the VTR 23 is input to the TV format converter 24, which converts the PAL format video signal into an NTSC format video signal. T
The V format conversion device 24 converts the field frequency and number of scanning lines of the input video signal and the modulation method of the color signal into a desired TV format using digital memory, a color demodulator, a modulator, etc. is configured to print. After the above process, the playback signal of the different format videotape (for example, PAL video signal) is transmitted to the NT in Japan.
Converted to SC video signal, T%' of NTSC system
It becomes possible to display the image on the receiver 22.

FIG. 4 is a connection diagram when creating a video tape of a different format. In FIG. 4, if you want to record scenery and features in Japan with a video camera 25 and send the videotape to a friend in West Germany, for example, you can use the video camera 25 in Japan.
Since it is an NTSC system, even if you send a videotape recorded directly on a VTR, it will not work in West Germany where the PAL system is used.
Cannot be played on TR. In this case, after inputting the video signal output of the video camera 25 to the TV format converter 24 and converting it from the NTSC format to the PAL format,
The information is recorded on a PAL VTR 23 to create a PAL videotape 2l.

As mentioned above, in the past, in order to play back a different format videotape and display it on a TV receiver in Japan, or to create a different format videotape, it was necessary to use a different format VTR 23 and a T.
A V format conversion device 24 was required.

Moreover, it is difficult to obtain a VTR 23 of a different format in Japan, and most TV format converters 24 are large and expensive devices installed at broadcasting stations and video software productions. It was not easy to easily watch or create a different format videotape.

However, in recent years, with the increase in the number of overseas travelers and students studying abroad, and the internationalization of schools, companies, government offices, etc., exchanges with countries with different TV systems have become active, and word communication using videotapes has progressed. Even at home, people are now watching different types of videotapes and communicating with people overseas through videotapes. Under such circumstances, T.
VTRs have also been developed in which a V format converter is built into a VTR at a low cost and can be used to create and play back video tapes of different formats at home.

FIG. 5 is a block diagram of a conventional VTR with a built-in TV format conversion device (hereinafter referred to as a TV format conversion VTR).

In FIG. 5, the output end of the changeover switch 34 that switches between the output of the tuner 32 to which the receiving antenna 3l is connected and the video signal input terminal 33 is connected to the input changeover switch 35 (
RBC) side. A playback (PB) connected to this recording side and the output end of the VTR recording and playback processing circuit 36.
The output end of the input changeover switch 35 that switches between the two sides is connected to the TV format conversion circuit 37 and the recording side of the input changeover switch 38. The output terminal of the TV system conversion circuit 37 is VT.
It is connected to the R recording/reproduction processing circuit 36 and to the reproduction side of the input selector switch 38 . Furthermore, V.T.
A recording/reproducing head 39 is connected to the R recording/reproducing processing circuit 36 . Further, the system selection switch 40 is connected to the TV system conversion circuit 37 and the VTR recording/reproduction processing circuit 36, and converts to the selected TV system. A video signal output terminal 4l is connected to the output end of the input changeover switch 38 for switching between the recording side and the reproduction side.

A VTR with a built-in TV format converter configured as above
The operation will be explained below.

First, the playback system for a different format videotape will be explained. During reproduction, the recording/reproducing head 39 converts the magnetization information recorded on the video tape into an electrical signal, and the VTR recording/reproducing processing circuit 36 performs reproduction processing of the video signal. The VTR recording and playback processing circuit 36 has a signal processing circuit that is compatible with a plurality of TV systems. For example, when playing back a PAL videotape, the signal of the PAL system passes through the PAL playback processing circuit. Output as a video signal. This reproduced video signal (for example, PAL video signal)
is input to the input changeover switch 25. Here, the input selector switches 35 and 38 can be switched between the recording mode and the playback mode of the VTR, and are set to the recording (Rec) side in the recording mode, and to the playback (P) side in the playback mode.
B) side is connected. Therefore, the reproduced video signal desired signal is input to the TV system conversion circuit 37, where it is subjected to conversion processing to the TV system. The conversion process is selected using the system selection switch 40. For example, PAL system is selected from N
By setting the mode for conversion to the TSC system using the system selection switch 40, the TV system conversion circuit 37 converts the PAL system to the NTSC system and outputs the converted signal.

The converted video signal passes through the changeover switch 38 and is output from the video image signal output terminal A4I. By connecting a TV receiver of the converted TV system to this video signal output terminal 4l, it becomes possible to display video.

Next, we will explain the process of creating a different type of videotape, that is, the recording system. When the video source to be recorded is a broadcast wave, the tuner 32 selects the signal received by the receiving antenna 31, converts it into a video signal, and sends it to the TV using the selector switch 34.
feed on the side. Further, when recording video output from an external device (for example, a video camera or a VTR), the external device is connected to the video signal input terminal 33 and a video signal is supplied to the VIDEO side of the changeover switch 34. The changeover switch 34 selects a video source, and selects either the TV side or the VIDEO side. The selected video signal is sent to the TV format conversion circuit 3 via the input selector switch 35.
7 is input. The TV format conversion circuit 37 performs conversion processing to the TV format selected by the format selection switch 40, and supplies the converted signal to the VTR recording/reproduction processing circuit 36. The VTR recording/reproduction processing circuit 36 performs recording signal processing corresponding to the TV system selected by the system selection switch 4θ. For example, when the mode selection switch 40 selects a mode to convert the NTSC system to the PAL system, the PA
It is configured to perform L method recording processing, and the VT
After the recording process is performed in the R recording/reproducing processing circuit 36, the recording/reproducing head 9 records the data on a video tape.

In this way, after playing a different format videotape, the TV format can be converted and displayed on a domestic TV receiver, or the format of a domestic video source can be converted to easily create a different format videotape. be able to.

Problems to be Solved by the Invention However, in the above conventional configuration, when creating a different format videotape (during recording), the video signal output terminal 4l
A video signal that does not pass through the TV format conversion circuit 37 is outputted to. Therefore, in an attempt to simultaneously create multiple videotapes of different formats, the recording VTR was connected to the video signal output terminal 4.
It was not possible to create a different format videotape even if I connected it to L. In addition, a TV receiver is connected to the video signal output terminal 41, and the T received by the receiving antenna 3l and the tuner 32 is
When displaying a V broadcast, if the TV format of the received TV broadcast and the TV format of the TV receiver are different, the video cannot be displayed on the TV receiver.

The present invention solves the above-mentioned conventional problems, and can be used alone as a TV format converter, and is a TV format converter that can create multiple video tapes of different formats and display video signals of different TV formats on a TV receiver. The purpose is to provide a VTR.

Including assignments. Means for Solving In order to solve the above problems, a TV format conversion VTR of the present invention is provided.
includes a TV format conversion circuit for converting the TV format of an input video signal, conversion mode selection means for selecting a conversion mode of the TV format conversion circuit, and recording the output video signal of the TV format conversion circuit on a video tape. a recording processing circuit for performing recording processing to perform a recording process, a video head for recording an output signal of the recording processing circuit onto a video tape, and a first output terminal for outputting an input video signal to be input to the TV format conversion circuit. and a second output terminal for outputting the output signal of the TV format conversion circuit.

Furthermore, the TV format conversion VTR of the present invention includes a TV format conversion circuit for converting the TV format of an input video signal, conversion mode selection means for selecting a conversion mode of the TV format conversion circuit, and the TV format conversion circuit. a recording processing circuit that performs recording processing to record the output video signal of the above onto a video tape, a video head that records the output signal of the above recording processing circuit onto the video tape, and an input video signal that is input to the above TV format conversion circuit. and a selection switch for selecting one of the output signals of the TV format conversion circuit and an output terminal for outputting the output signal of the selection switch.

Operation With the above configuration, the TV format conversion circuit converts the TV during recording.
It is now possible to output the image signal after format conversion processing to the output terminal, allowing you to connect another VTR to create a videotape of a different format, or monitor TV broadcasts with a TV receiver of a different format. It becomes possible.

EXAMPLES Hereinafter, examples of the present invention will be described with reference to the drawings.

FIG. 1 shows a TV system conversion VT showing a first embodiment of the present invention.
It is a block diagram of R. In FIG. 1, the output of the tuner 2 and the video signal input terminal 3 connected to the receiving antenna l are shown.
The output terminal of the changeover switch 4 for selecting one of the video signals is connected to the recording side of the input changeover switch 5 for recording and playback, and the playback side is connected to the VTR recording and playback circuit 8. Select the video signal output of changeover switch 4,
Further, at the time of reproduction, the reproduction output of the VTR recording and reproduction circuit 8 is selected. Furthermore, the TV format conversion circuit 6 located after the manual changeover switch 5 is a circuit that converts the TV format, and uses digital memory to convert the number of scanning lines and field frequency, and uses a color signal demodulator and modulator. The color signal modulation method is converted. The system selection switch 7 is connected to the TV system conversion circuit 6, selects a conversion mode between TV systems, and sends the mode information to the TV system conversion circuit 6. A VTR recording and reproducing processing circuit 8 subsequent to the TV format converting circuit 6 performs recording and reproducing processing of video signals compatible with a plurality of formats. The video head 9 is connected to a VTR recording/playback processing circuit 8. Furthermore, the changeover switch IO selects the output of the changeover switch 5 during recording, and is used during playback.

The operation of the above configuration will be described below.

First, during recording, the video signal selected by the changeover switch 4 is inputted to the TV format conversion circuit 6 via the changeover switch 5, where it is converted to the TV format selected by the format selection switch 7. The video signal converted to the desired TV format is subjected to recording processing in a VTR recording/reproduction processing circuit 8, and recorded on a magnetic tape by a video head 9. Further, the video signal during recording, that is, the output signal from the changeover switch 5, is outputted to the video signal output terminal l2 via the changeover switch 10, and can be monitored on a TV receiver.

T In general, the video source for recording and the TV system of the λ■ receiver for monitoring are often the same.For example, in ordinary homes in Japan, NTSC TV broadcasts, video camera output, etc. are common video sources. The TV receiver for the N monitor, which is the source, is of the NSC system. Therefore, by using the video signal output terminal l2 for normal monitor output, it is possible to monitor the video source during recording.

On the other hand, if it is desired to simultaneously create a plurality of recording tapes of different formats, it is necessary to connect the output of the TV format conversion circuit 6 to other VTRs. In that case, by connecting another VTR to the video signal output terminal If, it is possible to simultaneously create a plurality of recording tapes of different formats.

In addition, in areas overseas where multiple TV systems coexist, the TV system for the video source and the TV system for the monitor
Even when the V system is different, it can be handled by using the video signal output terminal 11. That is, the video signal selected by the changeover switch 4 is converted to the TV format of the monitor TV receiver by the TV format conversion circuit 6, and is sent to the video signal output terminal 11.
It can be monitored using a monitor TV receiver connected to the .

Next, the operation during playback will be explained. The video information on the video tape is reproduced by a video head 9, subjected to reproduction processing by a recording and reproduction processing circuit 8 of the VTR, and then inputted to a TV format conversion circuit 6 via a changeover switch 5. Here, after being converted to the desired TV system selected by the system selection switch 7, the signal is output to the video signal output terminal 12 via the changeover switch IO. By connecting a TV receiver to the video signal output terminal I2, the TV format conversion circuit 6 can be used during recording.
By configuring the output to be outputted to the video signal output terminal 11, other VTRs can be connected to this video signal output terminal 1l.
It is possible to simultaneously create multiple video tapes of different formats with converted TV formats.

Also, even if the TV format of the video source and the TV receiver for monitoring are different, by connecting the TV receiver to the video signal output terminal l1, the TV format of the video source can be converted to the TV format of the TV receiver for monitoring. It can be projected.

As can be seen from the above configuration, the video signal output terminals l1 and l2
It is necessary to provide two systems of output terminals. However, under actual usage conditions, the video signal output terminals 11 and 12
It is thought that there are few cases where TV format conversion is performed using both at the same time. That is, in areas where only one TV system exists, the TV system of the video source and the TV receiver are the same, and in that case, the video signal output terminal 12 is used.

In addition, in areas where multiple TV systems coexist, the video source may be connected to a TV receiver with a different TV system, or to another VTR.
If you want to create a recording tape with a converted TV system by connecting it, you can use the video signal output terminal l1. Therefore, a configuration in which the video signal output terminals l1 and 12 are shared by one system of output terminals and the output state is switched depending on the usage situation is considered to have almost no problem in practice. The configuration in this case is shown in FIG.

The second embodiment will be described below with reference to FIG. Here, the main difference from the configuration of the first embodiment shown in FIG. 1 is that a changeover switch 13 is provided and a video signal output terminal
The difference is that the output signals of 4 are switched. That is, when the input source and monitor TV system are the same during recording, the changeover switch I3 is turned to the A side so that the video signal before passing through the TV system conversion circuit 6 is output to the video signal output terminal. Also, check the input source and the T of the monitor TV receiver.
If the V format is different, or if you connect another VTR to the video signal output terminal l4 to create a recording tape whose TV format has been converted, move the selector switch l3 to the B side and select the T
The output of the V format conversion circuit 6 is output to a video signal output terminal l4.

In this way, by switching between the signal before passing through the TV format conversion circuit 6 and the signal after passing through the TV format conversion circuit 6 using the changeover switch l3, two types of output signals are outputted from the image copying signal output terminal l4 depending on the usage situation. This makes it possible to obtain the same effect as the first embodiment (FIG. 1) of the present invention.

As can be seen from FIG. 2, the changeover switch lO for switching signals between the recording system and the playback system and the above-mentioned changeover switch l
3 switches the signal before passing through the TV system conversion circuit 6 and the signal after passing through it, so if either the changeover switch 10 or the changeover switch 13 is provided, one can be omitted. Yes, and in this case, the configuration is simpler.

Effects of the Invention As described above, according to the present invention, by configuring the video signal output terminal during recording to be able to output both a signal before TV format conversion and a signal after TV format conversion, Even if the TV format of the TV receiver is different, you can convert the TV format and monitor it, and it is also possible to connect another VTR and record the video signal after converting the TV format. It is possible to easily create a plurality of converted recording tapes at the same time.

[Brief explanation of drawings]

FIG. 1 shows a TV system conversion VT showing a first embodiment of the present invention.
2 is a block diagram of a TV format conversion VTR showing a second embodiment of the present invention, FIG. 3 is a block diagram of a conventional different format video tape playback, and FIG. 4 is a block diagram of a conventional different format video tape. FIG. 5 is a block diagram of a conventional TV format conversion VTR. 6... TV format conversion circuit, 7... format conversion switch, 8 VTR recording/playback processing circuit, 9... video head 11, 12, 14... video signal output terminal, 13...
Changeover switch.

Claims (1)

[Scope of Claims] 1. A television format conversion circuit for converting the television format of an input video signal, and conversion mode selection means for selecting a conversion mode of the television format conversion circuit;
a recording processing circuit that performs recording processing for recording the output video signal of the television format conversion circuit onto a video tape; a video head that records the output signal of the recording processing circuit onto a video tape; and the television format conversion circuit. A television system conversion video tape recorder comprising a first output terminal for outputting an input video signal input to the television system conversion circuit and a second output terminal for outputting an output signal of the television system conversion circuit. 2. a television format conversion circuit for converting the television format of an input video signal; and conversion mode selection means for selecting a conversion mode of the television format conversion circuit;
a recording processing circuit that performs recording processing for recording the output video signal of the television format conversion circuit onto a video tape; a video head that records the output signal of the recording processing circuit onto a video tape; and the television format conversion circuit. A television format conversion video tape comprising a selection switch for selecting either an input video signal input to the television format conversion circuit or an output signal of the television format conversion circuit, and an output terminal for outputting the output signal of the selection switch. recorder.