JPH04243384A - Identification signal recording and reproducing device for vtr - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

[Detailed description of the invention]

0001

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an identification signal recording and reproducing apparatus for use in a VTR.

0002

[Prior Art] In recent years, in television broadcasting, audio multiplex broadcasting that broadcasts dual audio or stereo audio in two languages, etc. has been increasing.
Also, devices that can receive, record and reproduce audio multiplexed signals are becoming popular.

[0003] Hereinafter, with reference to the drawings, the conventional VTR
I will explain about it. FIG. 5 is a block diagram of an example of a conventional VTR. In FIG. 5, 3 is a color signal recording processing circuit;
4 is a color signal reproduction processing circuit, 6 is a comb filter, 7 is a video tape, 8, 14, 15, 16, 28 are input terminals,
13, 23, 24, 25 are output terminals, 17 is a luminance signal recording processing circuit, 18 is a first audio signal recording processing circuit, 19
2 is a second audio signal recording processing circuit; 20 is a luminance signal reproduction processing circuit; 21 is a first audio signal reproduction processing circuit; 22 is a second audio signal reproduction processing circuit; 26 and 27 are switches;
0 is a control signal generation circuit.

Regarding the VTR with the above-mentioned components,
The operation will be explained below. In FIG. 5, during recording, a luminance signal is input from the input terminal 14, subjected to FM modulation by the luminance signal recording processing circuit 17, and recorded on the video tape 7. A carrier color signal is inputted from the input terminal 8, converted into a low frequency converted color signal by the color signal recording processing circuit 3, and recorded on the videotape 7. A first audio signal m1 and a second audio signal m2 are inputted from input terminals 15 and 16, and are FM-modulated by a first audio signal recording processing circuit 18 and a second audio signal processing circuit 19, respectively, and recorded on a video tape. 7 is recorded.

[0005]

[Table 1]

[0006] As shown in Table 1, in the case of dual audio broadcasting such as bilingual broadcasting, the first audio signal m1 is the main audio signal and the second audio signal m2 is the sub audio signal. . In the case of stereo broadcasting, the first audio signal m1 is a left audio signal,
The second audio signal m2 is the right audio signal. Furthermore, in the case of monaural broadcasting, both the first audio signal m1 and the second audio signal m2 are the same monaural audio signal.

At the time of reproduction, the luminance signal r and the carrier color signal i are reproduced by the luminance signal reproduction processing circuit 20 and the color signal reproduction processing circuit 4, and are outputted to the output terminal 23 and the comb filter 6, respectively.
supplied to The carrier color signal i supplied to the comb filter 6 is outputted from the output terminal 13 after removing crosstalk components from adjacent tracks. On the other hand, the first audio signal reproduction processing circuit 21 and the second audio signal reproduction processing circuit 22 reproduce the first audio signal n1 and the second audio signal n2, respectively, and supply them to the switch 26 and the switch 27. .

The control signal generating circuit 30 switches the switch 2 in accordance with a signal o input from the input terminal 28 indicating whether the audio monitoring mode is the first, second, or third mode.
6 and the control signals p1 and p controlling the switch 27
Outputs 2. Switches 26 and 27 receive control signals p1 and p
2, one of the first audio signal n1 and the second audio signal n2 is selected and output to the output terminals 24 and 25. (Table 2) shows how it works. In the first mode, the switch 26 selects the first audio signal n1, and the switch 27 selects the second audio signal n2. In the second mode, both switches 26 and 27 select n1. Further, in the third mode, both switches 26 and 27 select n2.

[0009]

[Table 2]

0010

[Problems to be Solved by the Invention] However, as shown in Table 2, in the VTR configured as described above, the first
In this mode, when playing double audio such as bilingual audio, the main audio and sub audio are output at the same time, making it difficult to hear. Also,
In the second and third modes, when stereo audio is reproduced, only one of the left audio and right audio is output, respectively. Since no information is recorded to identify whether the audio signal is double audio or not, the user must judge for themselves whether the audio signal is double audio or stereo audio during playback. In the case of stereo audio, the user must select the second or third mode, and in the case of stereo audio, the first mode must be selected, which poses a problem in that switching the audio monitor mode is cumbersome.

SUMMARY OF THE INVENTION An object of the present invention is to provide a VTR identification signal recording and reproducing apparatus that solves the above-mentioned problems.

0012

[Means for Solving the Problems] In order to achieve the above object, the present invention provides a first method for creating a pilot signal whose phase is inverted by 180 degrees every horizontal scan at the color subcarrier frequency in a color under type VTR. and a first identification signal during the horizontal blanking period if the first identification signal is input.
a second means for inserting the pilot signal created by the first means into the input carrier color signal and outputting it for a predetermined period of time, and outputting the input carrier color signal as it is when the first identification signal is not input; means, third means for converting the frequency of the output of the second means into a low frequency converted color signal and recording it on a recording medium, and reproducing the low frequency converted color signal recorded by the third means from the recording medium. a fourth means for converting the frequency into a carrier color signal and outputting the signal; and a second means for detecting whether or not a pilot signal is inserted into the output of the fourth means for a second predetermined period during the horizontal blanking period. a fifth means for outputting an identification signal; and a frequency n.times. from the output signal of the fourth means.
and a sixth means for removing a component of fH (n is a natural number, fH is a horizontal scanning frequency).

[0013]

[Operation] With the above configuration, the present invention can record and reproduce a signal that identifies whether an audio signal is a double audio signal, and uses whether or not the audio signal is a double audio signal each time it is played back. This eliminates the inconvenience of having to switch the audio monitor mode based on the user's own judgment.

Further, even when a videotape on which an identification signal is recorded according to the present invention is played back on a conventional VTR, no problem occurs because the identification signal is removed by a comb filter.

[0015]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, embodiments of the VTR identification signal recording and reproducing apparatus of the present invention will be described with reference to the drawings.

FIG. 1 is a block diagram of one embodiment of the present invention. In FIG. 1, 1 is a first means, 2 is a second means,
3 is a color signal recording processing circuit, 4 is a color signal reproduction processing circuit, 5 is a color signal recording processing circuit;
is the fifth means, 6 is a comb filter, 7 is a video tape, 8, 10, 14, 15, 16, 28 are input terminals, 13
, 23, 24, and 25 are output terminals, 17 is a luminance signal recording processing circuit, 18 is a first audio signal recording processing circuit, 19 is a second audio signal recording processing circuit, 20 is a luminance signal reproduction processing circuit, and 21 is a luminance signal recording processing circuit. A first audio signal reproduction processing circuit, 22 a second audio signal reproduction circuit, 26 and 27 switches, and 29 a control signal generation circuit. Figure 2 (a), (b), (c), (
d) are the first means 1, the second means 2, and
The configuration of the fifth means 5 and the comb filter 6 is shown. 3, FIG. 4, and (Table 3) are diagrams and tables for explaining the operation of FIG.

The operation of the VTR identification signal recording and reproducing apparatus having the above-mentioned components will be explained below.

In FIG. 1, during recording, a luminance signal is inputted from the input terminal 14, subjected to FM modulation by the luminance signal recording processing circuit 17, and recorded on the video tape 7. A carrier color signal is inputted from the input terminal 8, passes through the second means 2, is converted into a low frequency converted color signal by the color signal recording processing circuit 3, and is recorded on the video tape 7. A first audio signal m1 and a second audio signal m2 are inputted from the input terminals 15 and 16, and are FM-modulated by a first audio signal recording processing circuit 18 and a second audio signal recording processing circuit 19, respectively, and then converted into a video signal. recorded on tape 7.

Here, the first means 1 creates a pilot signal l whose phase is inverted by 180 degrees every horizontal scan at the color subcarrier frequency and supplies it to the second means. 2(a). A horizontal synchronizing signal c is input from the input terminal 9, and the burst gate pulse generating circuit 1
A burst gate pulse is created at 01 and supplied to the burst gate 102. A burst signal is extracted from the carrier color signal b input from the input terminal 8 at the burst gate 102 and supplied to the phase comparator 104 . A voltage controlled crystal oscillator (hereinafter referred to as VCXO) 105 outputs a carrier signal of color subcarrier frequency fSC to a phase comparator 104,
It is supplied to an inverter 106 and a switch 107. A phase comparator 104 compares the phases of the burst signal supplied from the burst gate 102 and the output of the VCXO 105, and calculates V
Controls CXO105. As a result, VCXO105
oscillates in synchronization with the burst signal of the carrier color signal b. The divide-by-2 circuit 103 divides the frequency of the horizontal synchronizing signal c by two to create a signal d that is inverted every horizontal scan, and supplies the signal d to the switch 107 . Inverter 106 converts the output of VCXO 105 to 180
The phase of the signal is inverted and output to the switch 107. switch 1
07 follows the output d of the divide-by-2 circuit 103, and the VCXO10
The output of the inverter 106 and the output of the inverter 106 are alternately selected and output for each horizontal scan. In this way, a pilot signal l whose phase is inverted by 180 degrees every horizontal scan at the color subcarrier frequency is created and supplied to the second means 2.

An example of the configuration of the second means 2 is shown in FIG. 2(b). A horizontal synchronizing signal c is input from the input terminal 9, and a gate pulse generating circuit 201 outputs a pulse for a predetermined period during the horizontal blanking period. An identification signal a indicating whether the audio signal is double audio is input from the input terminal 10 . AND circuit 202 is gate pulse generation circuit 20
Create the logical product e of the output of switch 1 and the identification signal a, and
Controls 03. When the identification signal a is input (in the case of double audio), the switch 203 inputs the pilot signal l generated by the first means for a predetermined period during the horizontal blanking period, as shown in FIG. 3(a). is inserted into the carrier color signal b and output. On the other hand, if the identification signal a is not input (not a double voice), the switch 203 outputs the carrier color signal b as is, as shown in FIG. 3(b).

At the time of reproduction, the luminance signal r and the carrier color signal i are reproduced by the luminance signal reproduction processing circuit 20 and the color signal reproduction processing circuit 4, and are outputted to the output terminal 23 and the comb filter 6, respectively.
supplied to The carrier color signal i supplied to the comb filter 6 is outputted from the output terminal 13 after removing crosstalk components from adjacent tracks. On the other hand, the first audio signal reproduction processing circuit 21 and the second audio signal reproduction processing circuit 22 reproduce the first audio signal n1 and the second audio signal n2, respectively, and supply them to the switch 26 and the switch 27. .

The fifth means 5 detects whether or not a pilot signal is inserted into the output i of the color signal reproduction processing circuit 4 during a predetermined period during the horizontal blanking period.
An example of the configuration is shown in FIG. 2(c). 11 and 504 are input terminals, 12 is an output terminal, 501 is a gate pulse generation circuit, 502 is a gate circuit, and 503 is a level detection circuit. When a pilot signal is inserted, that is, in the case of a double audio signal, the identification signal k becomes High as shown in FIG. 4(a). On the other hand, when no pilot signal is inserted, that is, when it is not a double voice signal, the identification signal k becomes Low as shown in FIG. 4(b).

The control signal generating circuit 29 is supplied from the fifth means 5 with a signal o input from the input terminal 28 and indicating whether the audio monitor mode is the first, second, or third mode. According to the identification signal k, control signals p1 and p2 for controlling the switch 26 and the switch 27 are output. The switches 26 and 27 select one of the first audio signal n1 and the second audio signal n2 according to the control signals p1 and p2 and output it to the output terminals 24 and 25. (Table 3) shows how it works.

[0024]

[Table 3]

In the case of dual audio and the first mode, both switches 26 and 27 select audio signal n1. In the case of dual audio and the second mode, both switches 26 and 27 select the second audio signal n2. In other cases, the switch 26 selects the first audio signal n1, and the switch 27 selects the second audio signal n2. That is, if the first mode is set, only the main audio is output in the case of double audio, and the left audio and right audio are output in the case of stereo audio. Furthermore, if the second mode is set, only the sub-audio is output in the case of double audio, and the left audio and right audio are output in the case of stereo audio. Furthermore, if the third mode is set, the main audio and sub audio are output in the case of double audio, and the left audio and right audio are output in the case of stereo audio. Therefore, people who listen to the main audio (Japanese) in bilingual broadcasts such as movies should set it to the first mode, and people who listen to the secondary audio (English, etc.) should set it to the second mode. There is no inconvenience. Furthermore, when it is desired to output the main audio and the sub audio at the same time, such as during dubbing, the third mode may be set.

On the other hand, the comb filter 6 has a 1H delay circuit (1H=1/fH) 6 as shown in FIG. 2(d).
01 and a subtraction circuit 602, it extracts 1 from the input signal.
By subtracting the signal delayed by H, the frequency n・fH
(n is a natural number, fH is a horizontal scanning frequency). Here, the color subcarrier frequency fSC is fSC =
455·fH/2, the pilot signal whose phase is inverted by 180 degrees every horizontal scan at the frequency fSC is removed by the comb filter 6. Note that this comb filter is the same in the conventional example shown in FIG.

As described above, according to the present invention, it is possible to record and reproduce a signal for identifying whether or not an audio signal is a double audio signal, and to check whether the audio signal is a double audio signal or not at the time of playback. This eliminates the trouble of having to switch the audio monitor mode on the user's own judgment.

Further, even when a videotape on which an identification signal is recorded in this embodiment is played back on a conventional VTR, no problem occurs because the identification signal is removed by the comb filter.

[0029]

As is clear from the above embodiments, according to the present invention, an identification signal can be recorded and reproduced, and a videotape on which an identification signal is recorded in this embodiment can be played back by a conventional VTR. Therefore, it is possible to provide an excellent VTR identification signal recording and reproducing apparatus that does not cause any trouble even when

[Brief explanation of the drawing]

FIG. 1 is a block diagram of a VTR identification signal recording and reproducing device according to an embodiment of the present invention.

[Figure 2] Block diagram showing the configuration of each part in Figure 1

[Figure 3] Diagram explaining the operation in Figure 1

[Figure 4] Diagram explaining the operation in Figure 1

[Figure 5] Block diagram of a conventional VTR

[Explanation of symbols]

1 First means 2 Second method 3 Color signal recording processing circuit 4 Color signal reproduction processing circuit 5. Fifth means 6 Comb filter

Claims (1)

[Claims] 1. In a color under type VTR, a first means for creating a pilot signal whose phase is inverted by 180 degrees for each horizontal scan at a color subcarrier frequency, and a first identification signal is input. When the first identification signal during the horizontal blanking period is input, the pilot signal created by the first means is inserted into the input carrier color signal for a first predetermined period during the horizontal blanking period. a second means for outputting the input carrier color signal as it is when the first identification signal is not input; and frequency converting the output of the second means into a low frequency conversion color signal and recording it on a recording medium. a fourth means for reproducing the low frequency converted color signal recorded by the third means from a recording medium, converting the frequency into a carrier color signal and outputting the same; fifth means for detecting whether or not a pilot signal is inserted into the output of the fourth means for a predetermined period of time and outputting a second identification signal; (n is a natural number, fH is a horizontal scanning frequency).
identification signal recording and reproducing device.