JPH08306133A - Digital recorder and digital recording/reproducing device - Google Patents

Abstract

PURPOSE: To record a digital signal on a recording medium at the time of, or on and after a preceding time of, operating a recording button for recording an input signal by arranging a delay memory in a signal processing circuit. CONSTITUTION: This device is a digital recorder in which an input signal is supplied to a signal processing circuit 14 and a recording digital signal processed by this signal processing circuit 14 is recorded on a recording medium T by a recording means 8. A delay memory 11 is provided so that it has a longer delay time than a time difference obtained by subtracting a delay time of the input signal due to the signal processing circuit 14 from a period until this recording means 8 starts recording with a recording start control signal supplied to the recording means 8. This delay memory 11 is inserted into the signal processing circuit 14.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a digital recording device and a digital recording / reproducing device.

[0002]

2. Description of the Related Art When a monitor is receiving a video signal from a video signal source such as a television tuner or a television camera, when the video signal is to be recorded on a magnetic tape by a digital VTR from a desired time, The recording button of the digital VTR is operated, but the magnetic tape is wound around the tape guide drum equipped with the rotating magnetic head, and the magnetic tape runs at a predetermined running speed by the cooperation of the capstan and the pinch roller. Since it takes time, the video signal is recorded on the magnetic tape by the rotary magnetic head from a time point delayed from the desired time point by a certain time.

When a video signal from a video signal source such as a television tuner or a television camera is being received by a monitor, the video signal is reproduced from a desired time by a disk recording / reproducing device such as a magnetic disk or a magneto-optical disk. When recording is to be performed on the disc, the record button of the disc recording / reproducing device is operated, but the disc is rotated at a predetermined number of revolutions by the spindle motor, and the heads such as the magnetic head, the optical head, and the magneto-optical head are placed on the disc. Since it takes a certain amount of time to move the image signal to a predetermined position, the video signal is recorded on the disk by the head from a time point delayed from the desired time point by a certain time.

[0004]

In the above-mentioned conventional example, even if the video signal being monitored is recorded on the recording medium from a desired time point, the recording of the video signal on the recording medium by the recording means is started. By the time a certain amount of time elapses, the initial portion of the video signal will not be recorded on the recording medium.

In view of the above point, the present invention records an input signal on a recording medium when the record button is operated to record an input signal, or when the record button is operated or before the record button. The present invention intends to propose a digital recording device that can be used.

[0006]

According to a first aspect of the present invention, there is provided a digital recording apparatus in which a signal processing circuit to which an input signal is supplied and a recording digital signal from the signal processing circuit are supplied to record the recording digital signal. In a digital recording apparatus having recording means for recording on a medium, a delay time of an input signal by a signal processing circuit is calculated from a time from when a recording start control signal is supplied to the recording means to when the recording means starts recording. A delay memory having a delay time equal to or longer than the time difference obtained by the subtraction is inserted in the signal processing circuit.

[0007]

According to the first aspect of the present invention, the delay memory causes the signal processing circuit to start from the time from when the input signal supplies the recording start control signal to the recording means to when the recording means starts recording. The input signal is delayed by a delay time that is greater than or equal to the time difference obtained by subtracting the input signal delay time.Therefore, when you try to record an input signal, when you press the record button, Input signals after the point of are recorded on the recording medium.

[0008]

Embodiments of the present invention will now be described in detail with reference to the drawings. First, an embodiment will be described with reference to FIG. Reference numeral 1 indicates a recording system of a digital VTR. Reference numeral 2 denotes a signal source of an analog video signal of a television tuner, a television camera, etc. The video signal from the signal source 2 is supplied to the monitor receiver 3 and the recording system 1 of the digital VTR.

The video signal from the signal source 2 is A of the recording system 1.
It is supplied to the / D converter 9 and converted into a digital video signal, and the digital video signal is transferred to a delay memory (for example, FI).
(FO memory: first-in / first-out memory) 11 and is delayed for a predetermined time based on control by the memory controller 12. The memory controller 12 is controlled by the system controller 5. The delayed digital video signal from the delay memory 11 is supplied to the encoder 14 and coded, and the coded digital video signal is amplified by the recording amplifier 15, and then is supplied to the rotary magnetic head of the tape guide drum 8. It is supplied and recorded on the magnetic tape T so as to form inclined tracks.

A recording start signal generated based on the operation of a recording button (not shown) from the input terminal 4 is a system controller (which has a built-in microcomputer and a digital VT).
R, which controls each part of R). Then, when the recording start control signal from the system controller 5 is supplied to the mechanical system controller 6, the mechanical system controller 6 causes the tape guide drum device (including the drum motor, pulls out the magnetic tape from the tape cassette, (Including means for winding the tape around the tape guide drum) 8 and other mechanical systems (capstan,
The reel 7 on the take-up side, the reel on the supply side, and the like, and a motor for driving these reels 7 and the like) are controlled to pull out the magnetic tape T from the tape cassette, and to wind the magnetic tape T around the tape guide drum device 8 in a predetermined manner. The magnetic tape T is wound at an angle, and the magnetic tape T is run at a predetermined constant speed by a capstan, a pinch roller, a take-up reel, and a supply reel.

After the recording start command signal is supplied from the system controller 5 to the mechanical system controller 6, the magnetic tape T is wound around the tape guide drum device 8 and the magnetic tape T starts to run at a predetermined constant speed. Let T _M be the time.
Further, the video signal from the signal source 2 has a delay amount T ₉ delayed by the A / D converter 9, a delay amount delayed by the delay memory 11 T _D , and a delay amount delayed by the encoder 14 T ₁₄ , the delay amount delayed by the recording amplifier 15 is set to 0. Also, the sum of the delay amounts T ₉ and T ₁₄ is T _K
And the delay amount by the signal processing circuit of the video signal.

Thus, in general, between the delay amounts T _M and T _K ,

[0013]

[Equation 1] T _K <T _M

There is a relationship of Therefore, the delay amounts T _M and T
The delay amount T _D of the delay memory 11 with respect to _K is

[0015]

[Formula 2] T _D ≧ T _M −T _K

If you choose to [0016], and later when the recording start control signal from the system controller 5 by operating the recording button is supplied to the mechanism system controller 6, or, T _D that point - (T _M -
The video signal from the signal source 2 after the time point T _K ) before is recorded in the digitized and encoded state on the magnetic tape T by the rotary magnetic head of the tape guide drum device.

When the signal source 2 is a signal source for digital video signals, the A / D converter 9 of FIG. 1 is unnecessary, and therefore the delay T _K is T _K = T ₁₄ .

Next, another embodiment of the present invention will be described with reference to FIG. In the embodiment of FIG. 1, the bit rate of the digital video signal from the A / D converter 9 is too high, and the delay memory (eg, FIFO) satisfying the equation (2) is satisfied.
If the memory) 11 cannot be configured, the digital video signal from the A / D converter 9 is supplied to the compressor 10 to reduce the bit rate and then supplied to the delay memory 11 for delaying the delayed digital signal. The video signal is supplied to the decompressor 13, the bit rate is increased to return to the original bit rate, and then supplied to the encoder 14. Other configurations of the embodiment of FIG. 2 are similar to those of the embodiment of FIG.

In this case, assuming that the delay amounts of the digital video signal by the compressor 10 and the decompressor 13 are T ₁₀ and T ₁₃ , respectively, the delay amount T _K of the signal processing circuit described in the embodiment of FIG. Substituting the sums of the quantities T ₉ , T ₁₀ , T _13, and T ₁₄ , the above equations (1) and (2) hold, as in the embodiment of FIG. If the signal source 2 is a digital video signal source, the A / D converter 10 is not required.
The delay amount T _K is the sum of the delay amounts T ₁₀ , T ₁₃ and T ₁₄ .

Next, another embodiment of the present invention will be described with reference to FIG. This embodiment is a modification of the embodiment shown in FIG. 2 and is a case where the expander 19 in the embodiment shown in FIG. 2 is moved to a reproducing system of a digital VTR. In this case, if the delay amount T _K of the signal processing circuit described in the embodiment of FIG. 1 is replaced with the sum of the delay amounts T ₉ , T ₁₀ , and T ₁₄ , the same as the above-described embodiment of FIG. Formulas of Formula 1 and Formula 2 are established.
If the signal source 2 is a digital video signal source, A
Since the / D converter 9 is unnecessary, the delay amount T _K is the sum of the delay amounts T ₁₀ and T ₁₄ .

The structure of the recording system 1 of the digital VTR is shown in FIG.
Since the decompressor 13 in the above embodiment is deleted, the duplicate description of the recording system 1 will be omitted. Next, the structure of the reproducing system 16 in the case of the embodiment of FIG. 3 will be described.

The rotary magnetic head of the tape guide drum device 8 amplifies the digital video signal reproduced from the magnetic tape T through the reproduction amplifier 17, and then supplies it to the decoder 18 corresponding to the encoder 14 of the recording system 1 for decoding. After that, the signal is supplied to the decompressor 19 corresponding to the compressor 10 to reduce the bit rate and return to the original bit rate.
The analog signal is supplied to the A converter 20 to be returned to the original analog video signal and output from the output terminal 21.

Further, in each of the above-mentioned embodiments, the video signal is recorded on the magnetic tape and is reproduced, but an audio signal, a data signal or the like may be used instead of the video signal.

Further, in the above-mentioned embodiment, the case where the digital signal is recorded on the magnetic tape by the rotary magnetic head of the tape guide drum device and is reproduced is described, but the digital signal is recorded by the magnetic head or the optical head. The present invention can be applied to the case of recording on a disk such as a magnetic disk, an optical disk, a magneto-optical disk, etc.

[0025]

According to the digital recording apparatus of the first aspect of the present invention, a signal processing circuit to which an input signal is supplied and a recording digital signal from the signal processing circuit are supplied, and the recording digital signal is recorded on a recording medium. In a digital recording apparatus having recording means for recording, the delay time of the input signal by the signal processing circuit is subtracted from the time from the recording start control signal is supplied to the recording means until the recording means starts recording. Since a delay memory having a delay time equal to or greater than the obtained time difference is inserted in the signal processing circuit, when the record button is operated to record the input signal, when the record button is operated, or It is possible to record the input signal after the earlier time point on the recording medium.

According to a second aspect of the present invention, in the digital recording apparatus of the first aspect of the present invention, compression means and expansion means corresponding to the compression means are inserted at the input side and the output side of the delay memory, respectively. Since the delay time in the compression means and the expansion means is included in the delay time in the signal processing circuit, when the record button is operated to record the input signal, when the record button is operated, or It is possible to record the input signal after the previous point in time on the recording medium, and when the bit rate of the digital signal supplied to the delay memory is too high, reduce the bit rate of the digital signal and then supply it to the delay memory. Can be delayed.

According to the third aspect of the present invention, the recording side signal processing circuit to which the input signal is supplied and the recording digital signal from the recording side signal processing circuit are supplied, and the recording digital signal is recorded on the recording medium. In a digital recording / reproducing apparatus having a digital recording system including means, a reproducing means for reproducing recorded contents of a recording medium, and a digital reproducing system including a reproducing side signal processing circuit to which a reproduced digital signal from the reproducing means is supplied, The delay time is equal to or more than the time difference obtained by subtracting the delay time of the input signal by the recording side signal processing circuit from the time from the supply of the recording start control signal to the recording means until the recording means starts recording. The delay memory is inserted into the signal processing circuit, the compression means is inserted into the input side of the delay memory, and the delay time in the compression means is recorded on the recording side. Since it is included in the delay time in the circuit and the expansion means corresponding to the compression means is provided in the reproduction side signal processing circuit, when the record button is operated to record the input signal, the record button is operated. The input signal after the time point or after that time can be recorded on the recording medium, and when the bit rate of the digital signal supplied to the delay memory is too high, lower the bit rate of the digital signal. Can be supplied to the delay memory and delayed.

[Brief description of drawings]

FIG. 1 is a block diagram showing an embodiment of the present invention.

FIG. 2 is a block diagram showing another embodiment of the present invention.

FIG. 3 is a block diagram showing still another embodiment of the present invention.

[Explanation of symbols]

 1 Recording system 2 Signal source 3 Monitor 5 System controller 6 Mechanism system controller 7 Mechanism system 8 Tape guide drum device 9 A / D converter 10 Compressor 11 Delay memory 12 Memory controller 13 Expander 14 Encoder 15 Recording amplifier 16 Reproduction system 17 Reproduction amplifier 18 Decoder 19 Expander 20 D / A converter

Claims (3)

[Claims] 1. A signal processing circuit to which an input signal is supplied,
In a digital recording device having a recording means for supplying a recording digital signal from the signal processing circuit and recording the recording digital signal on a recording medium, the recording means is supplied with a recording start control signal, and then the recording means. Is inserted into the signal processing circuit, the delay memory having a delay time equal to or longer than a time difference obtained by subtracting the delay time of the input signal by the signal processing circuit from the time until the recording starts. Digital recording device. 2. The digital recording apparatus according to claim 1, wherein a compression means and a decompression means corresponding to the compression means are inserted into the input side and the output side of the delay memory, respectively. A digital recording apparatus, wherein the delay time in the means is included in the delay time in the signal processing circuit. 3. A digital recording system comprising a recording side signal processing circuit to which an input signal is supplied and a recording digital signal supplied from the recording side signal processing circuit and recording the recording digital signal onto a recording medium. In a digital recording / reproducing apparatus having a reproducing means for reproducing the recorded contents of the recording medium and a digital reproducing system having a reproducing side signal processing circuit to which a reproduced digital signal from the reproducing means is supplied, recording on the recording means is started. A delay memory having a delay time equal to or longer than the time difference obtained by subtracting the delay time of the input signal by the recording side signal processing circuit from the time from the supply of the control signal to the start of recording by the recording means. It is inserted into the signal processing circuit, and compression means is inserted into the input side of the delay memory,
A digital recording / reproducing apparatus characterized in that the delay time in the compression means is included in the delay time in the recording side signal processing circuit, and decompression means corresponding to the compression means is provided in the reproduction side signal processing circuit. .