JP2532647B2 - Video tape recorder - Google Patents

Description

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a desired television standard by converting between different television standard systems in a video tape recorder (hereinafter referred to as VTR) for recording or reproducing a video signal. The present invention relates to a video tape recorder capable of producing a recording tape of a standard system and outputting a desired television standard system signal.

2. Description of the Related Art Television standard systems in various countries around the world are not unified and several types of signal formats are used. Typical television standard systems are NTSC system, PAL system and SECAM system.
It is well known that there are seeds and methods in which they are slightly modified. The three typical video signal formats are as follows. NTSC basically has an interlaced scan of 30 frames per second (field frequency 60 cycles), a frame scanning line number of 525, and a carrier frequency of a color signal of 3,579 MHz. The PAL system has an interlaced scan of 25 frames per second (field frequency of 50 cycles). ), The number of frame scanning lines is 625, and the carrier frequency of the color signal is 4,433 MHz, and the SECAM method is almost the same as the WAL method except that the two color difference signals of the color signal are line-sequentially transmitted by frequency modulation.

Now, household VTRs are generally designed and shipped so as to comply with the television standard system of the consumer country.For example, in Japan and the United States, it complies with NTSC signals and the rotation frequency of the rotary head is the field frequency. The signal of 26.5H (H indicates 1 line) for one field is recorded on one track and the carrier color signal of 3.579MHz is converted to the low frequency of 629KHz for recording. There is. For PAL areas such as Germany and China, the rotation frequency of the rotary head is set to 50Hz to match the PAL signal and one track is used.
The signal for 312.5H is recorded, and the color signal is 4.433MHz for 627K.
It is configured to perform low frequency conversion to Hz. Furthermore, for France, etc., it is configured to record the frequency-modulated color signal by frequency conversion to a low frequency or by counting down (division) in order to support the SECAM method. The reproduction output signal is also adapted to be output in the same signal format as the television receiver of each country conforms to the television standard system adopted in each country.

However, in some areas where both PAL and SECAM formats can be received in Europe, and in areas where multiple standard format sources such as the Middle East and Southeast Asia are mixed, VTRs that support multiple television standard formats are being shipped. .

In this way, home-use VTRs are designed and sold so as to correspond to the television standard system of the area, and therefore, for example, by reproducing the tape recorded in the PAL system by the VTR that is normally sold in Japan. It was impossible even if I tried to watch it, or tried to play the tape recorded in NTSC format in Germany. Also, in VTRs that support multiple television standard systems such as the Middle East, although you can play back tapes recorded with multiple systems, you can use other standard systems such as recording the NTSC source in PAL format. It was impossible to convert to the system and record.

Problems to be Solved by the Invention Recently, information in the world tends to be unified, and there is an increasing need for international exchange of images. In response to such needs, the current home VTRs must be said to be insufficient as mentioned above. In addition, NTSC, P
The standard television system names such as AL and SECAM are unfamiliar to general users and usually have no knowledge of which system is used in which country, so it is appropriate to let them specify the desired television system. Not.

In view of the above problems, the present invention provides an automatic operation by instructing a country name so that a conversion desired by an operator can be easily achieved even for an operator who does not have any knowledge about a television standard system. The present invention provides a video tape recorder intended to be easily used by all users, which is configured so that a television standard system corresponding to that country can be selected.

Means for Solving the Problems To solve the above problems, a video tape recorder of the present invention is a video tape recorder that handles a plurality of television standard systems, and can record or reproduce at least a plurality of standard system signals. A system conversion circuit that has a servo system and a video signal processing system that can be used, and that converts one television standard system signal into another television standard system signal by controlling the writing / reading of the memory based on the command of the memory control circuit. A mode in which an input television standard signal is converted into another television standard signal for recording or a reproduced television standard signal is converted into another television standard signal and output. Including the mode, the switch panel displaying the world map and the operator's target from the switch panel The system is equipped with a system selection circuit that selects the television standard system corresponding to the instruction by indicating the country, and the output of the system selection circuit showing the system conversion destination and the input television standard system at the time of recording showing the conversion source. , A television standard desired by the operator from the original television standard system signal for the conversion operation of the system conversion circuit in response to a command from the memory control circuit that receives the reproduced television standard system during reproduction and determines the conversion mode. It is configured to control the conversion operation to the system signal.

According to the present invention, by the above-mentioned configuration, if the operator designates the desired country on the switch panel on which the world map is drawn, the conversion operation is performed according to the designated country, and the signals of different standard systems are recorded. And output signals of different standard systems, and even if you do not have knowledge of the television standard system, you can easily create recording tapes with a system other than the standard system of your home country or play back tapes recorded in other countries. Can be viewed on the TV receiver of the home country, and it is possible to unify international video information via VTR.

Embodiment A video tape recorder according to one embodiment of the present invention will be described below with reference to the drawings. FIG. 1 is a block diagram showing an embodiment of a video tape recorder of the present invention. (A) is a recording system, 1 is an antenna terminal, 2 is a tuner, 3 is a video input terminal, 4 is an input selector switch, 5 is a format conversion circuit, and 10 is a target country switch panel operated by a user. , 31 are system selection circuits for selecting a television standard system according to the target country. Reference numeral 6 is a VTR recording processing system, 7 is a video output terminal, 8 is a rotary head, and 9 is a servo system. 35 is an RF converter whose output is RF
Connected to terminal 36 as output. (B) shows a reproduction system, and a reproduction processing system 11 is arranged between the rotary head 8 and the system conversion circuit 5.

The operation of the video tape recorder configured as described above will be described. Assuming that this video tape recorder is used in Japan, the operation of the recording system in (a) will be described first. The TV radio wave input from the antenna terminal 1 is tuned and demodulated by the tuner 2 and appears at the TV terminal of the input selector switch 4 as a so-called NTSC composite signal. Now, assuming that a TV signal is selected by the input selector switch 4, this NTSC signal is converted to the system conversion circuit 5.
Is applied to The system conversion circuit 5 is a circuit that realizes mutual conversion of the television standard system based on the output of the system selection circuit 31. For example, if NTSC is selected by the system selection circuit 31, the input to the system conversion circuit 5 is Since it is an NTSC signal, the system conversion circuit 5 is in the passing state and outputs the NTSC signal as it is. Then, a command to output the NTSC signal is transmitted to the servo system 9 and the recording processing system 6. Therefore, the servo system 9 supplies control signals to the capstan motor, the cylinder equipped with the rotary head, and the control head for recording the control signal so that the NTSC signal can be recorded. The recording processing system 6 receives the NTSC signal and performs appropriate processing such as enhancement and frequency modulation so that the rotary head 8 records the signal. At this time, the NTSC signal which is the input of the format conversion circuit 5 is output to the video output terminal 7. An RF signal obtained by converting the NTSC signal by the RF converter 35 is output to the terminal 36. In this way, when the system selection circuit 31 selects NTSC, it operates exactly the same as the conventional domestic VTR.

Next, assuming that the system selection circuit 31 selects the PAL system, the system conversion circuit 5 converts the input NTSC signal into a PAL signal, and the servo system 9 and the recording processing system 6 operate so as to record the PAL signal. . Therefore, the NTSC signal input to the antenna terminal 1 and selected and demodulated by the tuner is PAL.
It is recorded on the magnetic tape by the rotary head 8 in a signal format. At this time, the NTSC signal before conversion is output to the video output terminal 7 and can be monitored by an ordinary NTSC receiver in Japan. NT broadcast as above
It is possible to create a recording tape in a PAL system different from the SC television standard system.

Furthermore, when the input selector switch 4 is selecting a video signal, a signal applied to the video input terminal 3, for example, a reproduction signal from another VTR can be converted into a PAL signal by the system conversion circuit 5 and recorded. In the end, it is possible to dubb the video information recorded by the NTSC system by the PAL system.

In the above description, the system selection circuit 31 for selecting the television system is driven by a command from the target country switch panel 10. That is, if the user operates the switch of the country name "USA" on the target country switch panel 10, the system selection circuit 31 automatically selects NTSC based on that, and operates the switch of another country name "West Germany" to select the system. Circuit 31 automatically selects PAL. Target country switch panel 10
The matrix switches displaying the world map are arranged side by side, and the user only has to operate the country to be selected by himself, and knowledge of the television standard system and which system is adopted in which country is required. do not do. Therefore, it is possible to easily select the television standard system of the country desired to be selected. Here, the world map display has a feature that the operation part is easier to understand than a simple country name display.

In the above description, the conversion from the NTSC system to the PAL system has been described, but the reverse and conversion between other systems including the SECAM system can be easily realized by this configuration.

 The operation of the reproduction system of (b) is as follows.

Assuming that a tape recorded by the PAL system is put on this VTR, the signal is picked up by the rotary head 8 and subjected to processing such as de-emphasis and FM demodulation by the reproduction processing system 11, and the PAL signal is output at the output. Is played. In this case, which television standard system the recorded signal is is determined automatically by measuring the field frequency, for example. Then, a control command based on the determination result is given to the reproduction processing system 11 and the servo system 9.
Since TV receivers in Japan are compatible with the NTSC system, even if the reproduced PAL signal is directly input to the NTSC system TV receiver, the screen will not be normal and there will be no image. Even if it does, the image will be very unsightly.
Therefore, if "Japan" is operated by the target country switch panel 10, the NTSC system is selected by the system selection circuit 31, the command is transmitted to the system conversion circuit 5, and the system conversion circuit 5 receives the reproduction PAL which is given to its input. The signal is converted into an NTSC signal and output to the video output terminal 7. Therefore, if the video output terminal is connected to the video input terminal of the NTSC receiver, it can be viewed as a normal image. Also, since the RF output is available at terminal 36, it can be viewed by connecting it to the antenna terminal of the NTSC receiver. In other words, it becomes possible to monitor the tape recorded by the PAL system normally with the NTSC receiver. Of course, conversions from other television standards, including NTSC to PAL or SECAM, can easily be done.

FIG. 2 is an example of the switch panel 10 in FIG. 1, in which a world map is drawn, and the main countries are shown by displaying the country names on a matrix with leader lines. Below this country name, a touch switch is arranged so that it can detect which country name the operator has pressed.
Since a world map is displayed on the switch panel 10, when the operator selects a desired country, the operator can find it quickly and easily, as compared with the case where only the country name is displayed. If you display the flag instead of the country name, you can create a more visual panel.

FIG. 3 is a block diagram showing an embodiment of the system conversion circuit 5 in FIG. The composite video symbol applied to the input terminal 12 is separated into a luminance signal and a chrominance signal by the Y / C separation circuit 13, the luminance signal is digitized by the AD converter 14 and applied to the memory 20, and the chrominance signal is decoded by the decoder 15 by the NTSC. , P
The color difference signals are demodulated in accordance with the AL, SECAM, etc. methods, converted into color difference signals, digitized by the AD converter 16, and applied to the memory 20. The memory 20 is a digital memory in units of fields, and is controlled by the memory control circuit 21, and its write clock is generated by the clock generator 19 based on the sync signal obtained from the low pass filter 17 and sync separation circuit 18 from the input signal. Use the generated one. The read clock is given from the clock generator 22. Of the digital signals that have undergone the format conversion processing in the memory 20, the luminance signal is returned to analog by the DA converter 23, and the color difference signal is returned to analog by the DA converter 24, and then the encoder 25 is used for each television such as NTSC, PAL, SECAM. It is modulated into a carrier color signal conforming to the standard method. The mixer 26 mixes the luminance signal with the carrier color signal and outputs the composite signal with the format conversion to the output end 27.

The method conversion operation is performed as follows. Now consider the conversion from NTSC to PAL. NTSC has a field frequency of 60H
Since the number of scanning lines in one field is 525/2 and the PAL is 50 Hz and 625/2, respectively, it is necessary to convert the field frequency and the number of scanning lines. Therefore, the signal for one field is written in the memory 20 at a predetermined clock to be stored,
It is configured so that it can be read by a clock independent of writing. The memory control circuit is the television standard system of the conversion source input to it (for example, it is determined from the video signal input to the system conversion circuit at the time of recording, and at the time of reproduction, it is determined from the video signal of the tape reproduced) and the operator. Determines the conversion mode from the television standard system of the conversion destination to which conversion is desired. Memory control circuit 21 is NT
When a command is issued to convert from SC to PAL, 60 fields of NTSC are read as 50 fields in PAL in response to the field frequency conversion. In other words, this can be realized by controlling the memory so that one field is skipped every six fields. Also, since the conversion of the number of scanning lines needs to be changed from 525/2 to 625/2, the line memory in the memory 20 is used to interpolate from the preceding and following scanning line information to create new scanning line information. realizable. Such control is performed by selecting or calculating information in the memory by a control signal from the memory control 21.

On the contrary, the conversion from PAL to NTSC is performed by reading the 1 field twice every 6 fields for the field frequency conversion, and the conversion of the number of scanning lines can be realized by thinning out or calculating the scanning line information.

The SECAM system has the same field frequency and the same number of scanning lines as the PAL system, and differs in that the color signals are FM-modulated and multiplexed in the order of the forward line. It can be realized.

In addition to the method described in FIG. 3, it is easily inferred that a more advanced system conversion can be realized by adding a memory and performing interpolation between fields and frames.

FIG. 4 is a block diagram showing another embodiment of the present invention. In FIG. 1, the system conversion circuit 5, the target country switch panel 10, and the system selection circuit 3 which are separately arranged in the recording system and the reproducing system.
Point 1 is configured to be shared between recording and playback,
Since the recording / reproducing processing circuit 28 is also generally realized by switching the internal circuit, it is different in that it is configured and only the video input / output terminal is eliminated from the tuner / RF converter. The recording / reproducing selector switch (R / P selector) is arranged to switch the processing of the recording / reproducing processing circuit 28 and to switch the input to the system converting circuit 5 and the output to the video output terminal in the same manner as described in FIG. It realizes recording and playback of different television standard system.

FIG. 5 shows the target country operation switch panel 10 in the present invention.
Is a concrete circuit example of the method selection circuit 31, and the target country operation switch panel 10 surrounded by a broken line frame is a switch corresponding to each country.
Multiple a, b, c, ... g, h are arranged, and countries with the same television standard system are input to the NAND gate (or OR gate) 32, 33, 34 as a group. .

For example, if switch b corresponding to'Japan 'is closed, NA
The output of the ND gate 32 becomes high level'H ', which means that the system selection switch selects NTSC. Similarly, switches d, e, and f are input to the NAND gate 33 in countries that use the PAL system, and switches g and h in countries that use the SECAM system are NAND gates.
34 have been entered. With such a simple structure, even if the user does not have knowledge of the television standard system, it is possible to select the system simply by indicating the country name on the world map.

As described above, the present invention is a video tape recorder that handles a plurality of television standard systems, and is provided with a servo system and a video signal processing system capable of recording or reproducing at least a plurality of standard system signals, Also, a television standard system input is provided with a system conversion circuit that converts one television standard system signal into another television standard system signal by controlling writing and reading of the memory based on a command from the memory control circuit. A switch panel that displays a world map, including a mode for converting signals to other television standard signals for recording or a mode for converting reproduced television standard signals to other television standard signals and outputting A television corresponding to the instruction by the operator indicating the target country from the switch panel Equipped with a system selection circuit that selects the standard television system, and receives the output of the system selection circuit that indicates the system conversion destination and the input television standard system during recording and the reproduced television standard system during playback. By configuring the conversion operation of the system conversion circuit to control the conversion operation from the television standard system signal of the conversion source to the television standard system signal desired by the operator according to a command from the memory control circuit that determines the conversion mode. , PAL TV broadcasting in Japan with simple and easy operation
You can record it with a method and send it to a friend in the PAL area of Europe, take home European video software and watch it on Japanese TV, dubbing the recent situation of your family filmed with movie on PAL method to Europe You can use it in various ways, such as sending it to a family member who is staying at.

Also, if it is applied to a video tape recorder with video input / output terminals without the tuner / RF converter, it can be used in any country in the world, so if one model is produced, it can be supplied to all over the world. It can greatly contribute to the standardization of design and production.

As described above, the present invention is capable of unifying video information by breaking the wall of a television standard system in the world with a VTR, and exerting an extremely great effect of further expanding the use of a video tape recorder as video information means. Is.

[Brief description of drawings]

FIG. 1 is a block diagram showing an embodiment of the present invention, FIG. 2 is a front view of a target country switch panel used in the present invention, and FIG. 3 is a block diagram showing an embodiment of a system conversion circuit used in the present invention. FIG. 4 is a block diagram showing another embodiment of the present invention, and FIG. 5 is a circuit diagram showing a concrete configuration example of the system selection circuit used in the present invention. 2 ... tuner, 3 ... video input terminal, 4 ... input selector switch, 5 ... method conversion circuit, 6 ... recording processing system,
7 ... video output terminal, 8 ... rotary head, 9 ... servo system, 10 ... target country switch panel, 11 ... playback processing system, 20 ... memory, 21 ... memory control circuit, 1
9,22 …… Clock generator, 31 …… Method selection circuit, 32,33,
34 …… NAND gate, 35 …… RF converter, 36 …… RF output terminal.

Claims (2)

(57) [Claims] 1. A video tape recorder handling a plurality of television standard systems, comprising a servo system and a video signal processing system capable of recording or reproducing at least a plurality of standard system signals, and one television standard. It is equipped with a system conversion circuit that converts the system signal into another television standard system signal by controlling the writing / reading of the memory based on commands from the memory control circuit, and converts the input television standard system signal into another television standard system signal. Operates from a switch panel displaying a world map and the switch panel, including a mode for converting to a standard format signal for recording or a mode for converting a reproduced television standard format signal to another television standard format signal and outputting. Chooses a television standard system that corresponds to the instruction by the person instructing the target country The system selects a conversion mode by receiving the output of the system selection circuit indicating the system conversion destination and the input television standard system during recording indicating the conversion source and the reproduced television standard system during reproduction. A video tape characterized in that the conversion operation of the system conversion circuit is controlled by a command of the memory control circuit from the conversion source television standard system signal to the television standard system signal desired by the operator. Recorder. 2. A switch panel displaying a world map,
The video tape recorder according to claim 1, wherein a country name or a national flag is also displayed.