JP3006119B2 - Signal recording / reproducing device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a signal recording / reproducing apparatus capable of simultaneously recording and reproducing an audio signal in both an analog recording system and a digital recording system.

[0002]

BACKGROUND ART FIG. 3 is a block circuit diagram of a speech portion of the audio portion and the satellite broadcast tuner of VHS system VTR.
In the figure, 300 is satellite broadcasting tuner, the audio signal processing circuit 301 the received satellite broadcast antenna, not shown, 302 digital interface (hereinafter,
A digital-to-analog converter (hereinafter referred to as "DAC"); 304, an output terminal for an analog signal; 305, an output terminal for a DIF signal; 306, a VTR; Terminal, 308 is a Hi-Fi (HIFI) recording signal processing circuit, 309 is a normal recording signal processing circuit, and 310 is an HI
FI recording signal, 311 is a normal recording signal, 312 is a HIFI reproduction signal reproduced from a magnetic tape (not shown), 313 is a normal reproduction signal, and 314 is a HIFI reproduction signal.
An I reproduction signal processing circuit, 315 is a normal signal reproduction processing circuit, 316 is a selection circuit for selecting any one of three inputs, and 317 is an analog signal output terminal. Also, 1
Reference numeral 20 denotes an analog recording processing circuit, and 121 denotes an analog reproduction processing circuit.

FIG. 4 shows a recording pattern of a signal recorded on a magnetic tape.
Is the video signal and HIFI recorded by the rotating head.
Recording tracks 322 of recording signals indicate recording tracks of normal recording signals recorded by the fixed head, and video signals and HIFI recording signals are recorded on the surface layer and the deep layer of the magnetic tape 320 by different heads. .

Next, the operation will be described. Digital signal output from the audio signal processing circuit 301 of the satellite broadcasting tuner 300, while being converted into an analog signal by DAC303, predetermined DIF format such standard CP-processor 340 of the Electronic Industries Association of Japan in DIF modulation circuit 302 And output from the terminal 305. VTR3
Reference numeral 06 performs signal processing for bias recording of the analog signal input from the terminal 307 by the normal recording signal processing circuit 309, and records this signal 311 on the track 322 of the magnetic tape 320 with a fixed head.
An input analog signal is FM-modulated by an IFI recording signal processing circuit, and the modulated signal 310 is recorded on a track 321 of a magnetic tape 320 by a rotating head.

At the time of reproduction, a track 3 is
The reproduction signal 313 reproduced from 22 is returned to the original audio signal in the normal reproduction signal processing circuit 315. The reproduction signal reproduced from the track 321 by the rotary head is FM-demodulated by the HIFI reproduction signal processing circuit 314, and is restored to the original audio signal. The selection circuit 316
During recording, the analog input signal input to the terminal A is output from the terminal 317, and during reproduction, one of the reproduction signals input to the terminals B and C is selected and output from the terminal 317.

The above-described FM recording of an audio signal is added to perform high-quality recording / reproduction of audio. In order to maintain higher compatibility with a conventional VTR of a bias recording system, two types of FM recording are provided. The selection circuit 316 normally reproduces an FM recording signal. However, when the level of the reproduction signal is equal to or lower than a predetermined value, “the reproduction is not normal” or “FM recording is performed”. Not "
The normal reproduction signal input to the terminal C is selected and output.

[0007]

The conventional VTR is configured as described above, and the audio signal is recorded by FM. However, since it is an analog recording system, it is used for digital audio equipment such as a compact disk player. Such high-quality reproduction sound cannot be expected. SUMMARY OF THE INVENTION The present invention has been made to solve the above-described problems, and it is possible to obtain the same performance as a digital audio device by digitizing the audio of a VTR and to connect a magnetic tape only by connecting a digital interface. Above, digital voice,
VTR that can record and play back both analog sounds
The purpose is to obtain.

[0008]

According to the present invention, there is provided a recording / reproducing apparatus for transmitting a digital audio signal and mode information transmitted through a digital interface to a recording system.
A digital audio signal is converted to an analog signal and then recorded on a magnetic tape. If the mode information is in the digital mode, the received digital audio signal and an additional signal for identifying that the digitally recorded signal is an audio signal are added. Means for recording information on a magnetic tape and, when the mode information is in the analog mode, means for recording dummy data and additional information for identifying that the recorded signal is dummy data; To determine additional information,
If the digital recording signal is a voice signal, the digital voice signal is reproduced, and if the digital recording signal is dummy data, an analog voice signal is reproduced.

[0009]

According to the present invention, at the time of recording, additional information for discriminating between the digital mode and the analog mode is recorded on a magnetic tape, and at the time of reproduction, whether the signal is a digital signal or an analog signal is determined from the additional information, and digital recording is performed. If the received signal is dummy data, the signal recorded in analog can be reproduced and output. Therefore, signal recording without any loss of data is possible with only the digital interface, regardless of the mode of the received signal. Reproduction becomes possible.

[0010]

An embodiment of the present invention will be described below. In FIG. 1, reference numeral 107 denotes an input terminal of a digital interface, and reference numeral 106 denotes a DIF demodulation circuit for extracting a digital audio signal and mode information transmitted through the digital interface. 105 is a digital recording processing circuit.
The digital audio signal input from the IF demodulation circuit 106 is encoded for error detection or error correction, and a digital recording signal converted to a predetermined recording format is output together with additional information.

Reference numeral 115 denotes a system control for controlling each part of the circuit. Reference numeral 108 denotes a digital reproduction processing circuit which receives a digital reproduction signal 125 reproduced by a magnetic head, performs error correction processing, and corrects a digital audio signal and additional information. Is output. 109 is a selection circuit, DI
One of the outputs of the F demodulation circuit 106 and the digital reproduction processing circuit 108 is selected. 110 DAC, 123 for converting the digital audio signal into an analog audio signal for selecting either the output of the DAC110 analog reproduction processing circuit 12 1 in the selection circuit.

Next, the recording operation will be described. During recording, the selection circuit 109 selects the terminal 3a, the selection circuit 123 selects the terminal 4a, and during reproduction, the selection circuit 109 controls the terminal 3b, and the selection circuit 123 controls the terminal 4b so as to select the terminal 4b.

Digital interface format
Digital audio signal and a mode signal in is transmitted being input to the terminal 107 is demodulated by DIF demodulation circuit 106, a digital audio signal 106a this is demodulated is outputted to de <br/> Ijitaru recording processing circuit 105 At the same time, it is output to the terminal 3a of the selection circuit 109. At the same time, the demodulated mode information 106b is transmitted to the system control 11
5 is output.

Here, the mode information 106b indicates information relating to recording of a digital audio signal to be transmitted, and the following two modes can be defined. De Ijitarumodo: can be recorded remains digital digital audio signal to be transmitted. A Narogumo de: it can record converts the digital audio signal to be transmitted into an analog signal.

In recording by the digital interface, high-quality signal recording can be performed in the digital mode.
There is a problem that digital signals cannot be recorded. When such a recording is made, a reproduced sound cannot be obtained from the middle of the tape during reproduction. However, in the embodiment shown in FIG. 1, it is devised that such a problem does not occur.

That is, the digital audio signal output from the DIF demodulation circuit 106 is converted into an analog audio signal by the DAC 110 via the selection circuit 109, and any mode information is transferred to the magnetic tape via the analog recording processing circuit 120. The analog audio signal output of the DAC 110 is recorded on the terminal 31 via the selection circuit 123.
7 is output.

If the received mode information is in the digital mode, the system control 115 sends the received digital audio signal and additional information indicating that the digital audio is recorded to the digital recording processing circuit 105.
Is converted into a predetermined format and recorded, and the output of the digital recording processing circuit 105 is, for example,
The output signal 310 of the HIFI recording signal processing circuit 308 shown in FIG. 3 is recorded in the deep part of the magnetic tape by frequency multiplexing.

On the other hand, if the received mode information is the analog mode, the system control 115 records the dummy data instead of the received digital audio signal and also records additional information indicating the dummy data. Controls the digital recording processing circuit 105. In this case, “0” is adopted as dummy data,
Since the dummy data is coded for error detection or error correction and recorded, no noise is generated even if the dummy data is erroneously reproduced due to a detection error of the additional information during reproduction.

Next, the reproducing operation will be described. A digital reproduction signal 125 of a predetermined format reproduced from a magnetic tape is subjected to error detection and correction processing by a digital reproduction
8a and additional information 108b are output separately, and the digital audio signal 108a
At 110, it is converted to an analog signal. When the reproduced additional information 108b indicates dummy data, the selection circuit 123 selects the terminal 4b. When the reproduced additional information 108b is digital audio, the selection circuit 123 selects the terminal 4a and outputs the selected terminal 4a to the terminal 317.
The system is controlled by system control.

As described above, signals can be recorded and reproduced without any loss of recording without relying on mode information only by the digital interface. Further, since the connection of the analog input is unnecessary, the connection is simple, and the analog input terminal and the circuit are unnecessary.

The apparatus having a digital input terminal and an analog output terminal has been described above. However, recording from a device without a digital interface and output to a device without a digital interface are also possible. FIG. 2 shows an example having digital input / output and analog input / output.

Referring to FIG. 1, reference numeral 103 denotes an analog-to-digital converter (hereinafter, referred to as "ADC") for converting an analog signal into a digital signal;
A selection circuit for selecting one of the outputs of the F demodulation circuit 106, a selection circuit 122 for selecting one of the outputs of the ADC 103 and the selection circuit A109, and a DI 113 for converting a digital audio signal into a signal of a predetermined DIF format.
An F modulation circuit 126 is a selection circuit for selecting either the digital input input from the terminal 107 or the output of the DIF modulation circuit 113. 127 is an analog input input from the terminal 101 or an output of the analog reproduction processing circuit 121. A selection circuit 114 for selecting whether or not, is an output terminal of the digital interface.

Next, the operation will be described. (A) When an instruction to record an analog input is given by a key input The system control 115 determines that the selection circuit 127 has the terminal 1a, the selection circuit 104 has the terminal 2a, and the selection circuit 109 has the terminal 2a.
Is the terminal 3a, the selection circuit 123 is the terminal 4a, the selection circuit 122 is the terminal 5b (or 5a),
Controls the terminal 6b to be selected.

The analog signal input from the terminal 101 is input to the ADC 103 via the selection circuit 127, converted into a digital signal, and recorded on the magnetic tape via the selection circuit 104 and the digital recording processing circuit 105. The digital signal selected by the selection circuit 104 is input to the DAC 110 via the selection circuit 109 and is converted into an analog signal.
0 is recorded on the magnetic tape. Also, the selection circuit 1
The digital signal selected at 09 is input to the DIF modulation circuit via the selection circuit 122, is converted into a predetermined digital interface format, and is output from the digital output terminal 114 via the selection circuit 126. At this time, the DAC1 is connected to the analog output terminal 112.
Ten outputs are output via the selection circuit 123.

(B) When an instruction to record a digital input is given by key input: The system control 115 determines that the selection circuit 104 has the terminal 2b, the selection circuit 109 has the terminal 3a, and the selection circuit 123 has
Controls the terminal 4a and the selection circuit 126 selects the terminal 6a. The digital input input from the input terminal 107 is recorded on a magnetic tape in the same manner as in FIG. At this time, the digital signal applied to the terminal 107 via the selection circuit 126 is output to the digital output terminal 114. Also, analog output terminal 1
12, the output of the DAC 110 is output via the selection circuit 123.

(C) When a Reproduction Operation is Instructed by Key Input The system control 115 determines that the selection circuit 127 has the terminal 1b, the selection circuit 109 has the terminal 3b, and the selection circuit 126 has the terminal 3b.
Control each terminal 6b. Also,
When the output of the digital reproduction processing circuit 108 is selected, the system control 115 controls the selection circuit 123 to select the terminal 4a and the selection circuit 122 to select the terminal 5b, and selects the output of the analog reproduction processing circuit 121. Controls the selection circuit 123 to select the terminal 4b and the selection circuit 122 to select the terminal 5a.

Normally, a high-quality digital reproduction processing circuit 1
08 is output from terminals 112 and 114,
When the reproduced additional information indicates the non-recording mode, or
As a result of the error detection, if the number of errors is abnormally large, or if the reproduction signal envelope of the digital recording signal is low, the output of the analog reproduction processing circuit 121 is supplied to the terminal 11.
2 and 114.

Next, the case where the output of the digital reproduction processing circuit 108 is output will be described. The output of the digital reproduction processing circuit 108 is output to the analog output terminal 112 via the selection circuit 109, the DAC 110, and the selection circuit 123, and the selection circuit 122 and the DIF modulation circuit 11
3 and output from the digital output terminal 114 via the selection circuit E126.

Next, the case where the output of the analog reproduction processing circuit 121 is output will be described. Analog playback processing circuit 1
21 is output from a terminal 112 via a selection circuit 123 and input to an ADC via a selection circuit 127 to be converted into a digital signal. This digital signal is transmitted via a selection circuit 122 to a DIF modulation circuit 113. And is converted into a predetermined format.
6 and output from the terminal 114.

According to the embodiment of FIG. 2, if the device to be connected has a digital interface, recording and reproduction can be performed only by digital input / output signals, and even if the mode of the input signal changes during recording. No record leakage occurs. Further, since the additional information is also recorded at the same time, it can be reproduced regardless of the mode of the recorded signal.

Although the above description has been made with respect to a VTR, a similar effect can be obtained even with a recording / reproducing apparatus using only audio. In the above embodiment, the case has been described recording of the received signal in a digital interface satellite broadcast tuner is built in VTR, the audio signal processing circuit shown in FIG. 3 301
Is replaced with the audio signal output of the DIF demodulation circuit 106, and a signal corresponding to the mode information of the received audio signal is supplied to the system control 115, whereby a similar effect can be obtained.

[0032] In addition, not satellite broadcast tuner only, CD
It goes without saying that the same effect can be obtained by applying the present invention to the recording of audio signals from digital audio equipment. Further, in the above embodiment, the digital audio signal is
The M signal is frequency-multiplexed and recorded in the deep part of the magnetic tape. However, the same effect can be obtained by applying the present invention to a recording apparatus that performs three-layer recording in the order of video signal, FM audio signal, and digital audio signal from the surface of the magnetic tape. Is obtained.

[0033]

As described above, according to the present invention, the VTR
The digital audio signal transmitted by the digital interface is converted to an analog signal by the digital audio processing circuit and recorded on a magnetic tape.
Recording the received digital audio signal and additional information indicating that the digital audio signal was recorded on a magnetic tape,
In the case of the analog mode, dummy data and additional information indicating that the dummy data has been recorded are recorded on the magnetic tape instead of the digital audio signal. However, since analog recording is performed, there is no loss of recording, and the reproduction of the part where the dummy data is recorded can be automatically reproduced in analog with the additional information. A signal recording / reproducing apparatus capable of performing recording and reproduction without recording loss only by the interface is obtained.

[Brief description of the drawings]

FIG. 1 is a block circuit diagram of an audio recording / reproducing apparatus according to an embodiment of the present invention.

FIG. 2 is a block circuit diagram of an audio recording / reproducing apparatus according to another embodiment of the present invention.

FIG. 3 is a block circuit diagram of a satellite broadcast tuner and a conventional audio recording / reproducing apparatus.

FIG. 4 is a diagram showing a recording pattern on a magnetic tape.

[Explanation of symbols]

104, 109, 122, 123, 126, 127 selection circuit 105 digital recording processing circuit 106 DIF demodulation circuit 108 digital reproduction processing circuit 110 digital / analog conversion circuit 113 DIF modulation circuit 115 system control 120 analog recording processing circuit 121 analog reproduction processing circuit

Claims (1)

(57) [Claims] 1. A signal recording apparatus for receiving a signal in which a digital information signal and mode information relating to a process at the time of recording the digital information signal are multiplexed in a time-division manner, and recording and reproducing the digital information signal based on the mode information. In a reproducing apparatus, a digital / analog conversion circuit for converting the digital information signal into an analog signal, and a digital for generating a recording signal of a predetermined format by adding a code and additional information for error detection and correction to the digital information signal A recording processing circuit, an analog recording processing circuit that generates a signal suitable for recording on a recording medium based on the analog signal , and a control unit that controls the device based on the mode information. After converting the received digital information signal into an analog signal with a digital-to-analog conversion circuit, When the received mode information is digital recording mode, the received digital information signal is recorded on the recording medium via the digital recording processing circuit, and the received mode information is recorded on the recording medium via the analog recording processing circuit. In the case of the analog recording mode, dummy data is input to the digital recording processing circuit and recorded on a recording medium in a predetermined format together with additional information indicating that the dummy data is recorded. signal recording and reproducing apparatus characterized by digitally recorded signaled by so as to play discriminating whether the dummy data or a digital information signal on the basis of the information.