JPS58166508A - Sound signal reproducing device - Google Patents

Abstract

PURPOSE:To obtain a clear reproducing monitor sound which has a time axis corresponding to a low speed ratio by using an excellent reproducing sound signal among signal obtained by scanning on the same track plural times during low-speed reproduction. CONSTITUTION:Part of a servo specifying signal Servo Ref for phase control over drum rotation is supplied to a switching circuit part 9 consisting of a monostable multivibrator, etc. Consequently, the switching circuit part 8 supplies the signal to switching circuit parts 7 and 8 to generate a switching signal for video signals which demultiplexes sound signals and video signals reproduced by heads A and B respectively. By this switching signal, the switching circuit part 8 performs switching and selection to extract the video signals reproduced by the heads A and B so that they are put together in one continuous signal. This selectively extracted video signal consiting of a low-band converted color signal and an FM-modulated luminance signal is supplied to a video signal demodulation part 10.

Description

[Detailed description of the invention] @19 diagonal tracks formed on the tape using helical scanning, and time sharing with video notes]
The present invention relates to an audio signal reproducing device that reproduces and outputs an audio signal that has been encoded and recorded using a time axis pressure m.

This bridge device does not output an audio signal during low-speed playback. A certain %A compares the audio signal flowing from the track to the head with that during normal speed playback. ◎ Therefore, during the low-cost summer playback, the playback monitor sound may not be 8c, or even if one agrees, it may be falsely passed.
It was a playback monitor sound.

This is something that should be done in terms of book @ Ming era, ζ.
It is an object of the present invention to provide an audio signal reproducing device that is slow due to the high speed.

next. As an introduction to the audio signal reproducing device of this invention, we will explain the helical system 1-type VT& of the 9-overskin system applied to the 8-reproduction system of the present invention with reference to the park.

Figure 1 is a schematic diagram of the turning drum section, and Figure 2 is a four-way diagram of the entire recycled yarn.

Rotating dot ^(;J rotates in the direction of the arrow 1, and
On this rotating drum (1), heads A and B forming the rotating head #I4 are arranged facing each other at an angle of 180 in α. The magnetic tape (2) is wound around the circumferential surface of the drum (1) from point 0 to point 0 at an angle of 220 in β, which is approximately 60 square degrees greater than the conventional winding angle.

The guide pin 13) is inserted into the system (4) and travels in the direction of the arrow. Then, diagonal tracks are formed on the magnetic tape (2) by helical scanning. One time axis is displayed on each track, and an audio signal corresponding to one field of a video signal encoded in PCM and configured to be error correctable is low-frequency converted. The image signal is recorded by time division with one field of Wk image signal, which is composed of 4N of FM-modulated color signals and FM-modulated polarization signals.

Person, B head.

At normal speed [0% during playback, while rotating through an angle of about 60 degrees from point C to point d, the pitch polarization recorded in fy symbol division and p is recorded for each track, that is, one field. Scans and plays alternately once every minute, and selects the image number gi from point d to point 0 on a leapfrog that rotates at an angle of about 180 degrees. Scan and play.

On the other hand, during low continuous playback, the A and B heads repeatedly scan the same track while gradually changing the scanning position according to the low speed ratio, and recording is performed from the heads whose azimuths coincide. The audio signal and the wk polarization code are reproduced. For example, when the field is 0 Nyu at 115 times, the head with matching azimuth is 6 @ (1 & g 1st, 6th, 5th) as shown by the audio signal in @3 Figure ■. 2 @ (2nd and 4th times) 1 In total, the same track is scanned five times while gradually shifting the scanning position, and the audio decoding and furthermore the video signal are reproduced from the head whose azimuth matches. That is, the audio signal for one field and the video No. 141 for one field are repeatedly played back six times. In addition, in Figure 5, there is an i in the first half.
The track where 7 is placed is on the human head, and the azimuth is on the B head on the track scanned in the second half.
◎Also, during playback at N speed ff'), when the M and B heads alternately scan different tracks, the azimuth 4 can always be combined for playback. Like this ^
Add one additional width to each raw audio signal and video signal (15)
(6) and after 7, the switching circuit 1ts (force (8) is applied to each predetermined contact point as shown in FIG. 2).

On the other hand, the servo wind direction signal 5e that controls the phase of drum rotation
A part of the RVO EF is applied to a switching circuit section (9) composed of a monomulti-layer circuit. From this,
In the switching circuit section (9), the switching circuit section (7118
j) Forms a video signal switching signal for switching and dividing the audio signal and video signal reproduced from the A and B heads respectively. In this switching circuit (8), one person makes a switching selection in order to extract the video signals reproduced from each B head in a series. If the color signal is
The video signal composed of the modified exposure direct signal is given to the video polarization demodulation section α. and.

The color signal is high-frequency Rg& and the luminance signal is i? M
The video signal is converted back to the original video signal and output.

On the other hand, the switching circuit section (7) selects and extracts the frame signal from the frame and the signal from the switching circuit section (9).
signal is obtained. This signal is applied to an audio signal demodulator. The loud signal returns to the I section -αυ.

The time axis is output, and the audio signal, which has been converted into PCM and encoded into nine correction ratios, is detected and subjected to correction interpolation and the like. The time axis from the audio signal 1AsOυ is compressed and converted into PCM and is given to the control unit σ.

Two random access memories (hereinafter referred to as RAMs)1. ◎ Normally, when an audio signal is generated, each B head alternately scans different tracks and reproduces the audio signal, which is corrected by the U correction function. Then, the data is alternately written and stored in RAM I and HIJ (la) for each track, that is, for each audio signal of one signal and one word of WkgIi. However, the example is - RAMI (1
, 1 where the audio signal is written.

The audio signal written and stored in the other RAMIQa is successively output on the expanded original time axis. Jin's audio signals are converted into D-Music Sa! 9, which is analog-converted and returned to the original audio signal for output. Then, it becomes the Yasuo monitor sound.

On the other hand, when low speed j[f') is being generated, the control unit U is given an audio signal that has been repeatedly reproduced from the same track and subjected to correction interpolation, etc. according to the false progress ratio. Therefore, the control unit I has 0. −
Based on the CTL code that is transferred from the tape (2) to the identification head (not shown), the scanning state of the scanning head to the track is determined to be better if the *vh is changed. The expected audio signal is appropriately translated and written into and stored in, for example, an AMIα.

Then, one field of the audio signal stored in this RAM I is continuously repeated in accordance with the low speed ratio on the expanded original time axis, with one field as a unit section. In other words, it is continuously output over a period corresponding to 91 fields, which corresponds to a unit section where the time axis has been expanded due to low-speed playback, and the DM converter aω
is output through the , and becomes the playback monitor sound. During this time 1
The audio signal played from the next track is 8λM M (
11 and is updated. This will be explained in detail on the basis of FIG. 6 as a 175-times-speed fluoroscopic regeneration at a low speed ['14].

＠Like Ki, it is 115 times the same when you are alive.The analogy is #I6#I
Jl O) As shown in the 10th section, the audio signals for one field from the 11 tracks are passed through the audio signal section I11 1υ to the A head whose azimuth matches.

As shown in the figure, "1m town% odor" is given 6 times repeatedly to the control #bubutsu◆.In addition, "1m""2s"l in the middle
The analog signal rIL is actually in the encoded state indicated by the time axis pressure #i, and the control ma
4, the time axis is compressed as described above, and the audio signal of the PC'M version is given. however.

Good external appearance by track scanning of the head of the head [U, this is the tone that is clearly shown in Figure 6. Therefore, the audio signal reproduced by the 21st scan of the human head, which produces a sound pattern of the turtle azimuth based on the CTL decoding, that is, the δth scan of the M and B heads in total, is written in the MIQ head. be remembered.

Then, %RAMI (Immediately after being written and stored in the memory, the extended time axis becomes the original time axis, and is continuously repeated five times with one field as the half interval,
In other words, low speed! [It was created by student A in the 5th field period, which corresponds to a unit interval of 1 field with the time axis expanded five times, and then transferred to the 6th field through the DA converter.
The monitor audio is output as shown in ■. Then, the 511ai-th one is output one after another from B-mu Mlα4.
Then, the audio signal generated by the second scan with good accuracy by the B head whose azimuth coincides with the primary track (as shown in Figure 3 (2)) is written into the RAM 1 and stored. The time axis is extended tMk to the voice signal written and stored in the ``Rum MI (11'') from the AMI Qa to the bale where the 51st string was stringed, and the time axis becomes the same as before. Continuously set one field as the jIL interval.
＃& Return it and it will be issued.

In this way, the unit interval of the audio signal output with h return iia + leak is one field.

Because one field is as short as 1/40 ml, and because it is output repeatedly at low speed according to the ratio, you can clearly hear the high quality sound.
By each of Hitoshi and Figure 5 (^-).

Two different! Illustrate AJ1m.

Figure aI4 (to Bl) Another embodiment is that the output from one track written and stored in lume M1.Iaaal is as shown in Figure 4 (5). The audio signal for one field converted into an analog waveform and shown is further divided into six as shown in the figure, each of which is a unit section.Then, according to the reproduction far-to-direction ratio of 115 times, 114 on the original time axis expanded by each unit interval.
As shown in figure (U), this is a case in which each unit interval is made to correspond to the expansion of the time axis due to the reproduction of 1A times as many times as 5 times. Since the unit interval time is further shortened, the voice can be heard even more clearly.

#I written and stored in RAM1.lαaI as in the example 5.
Figure 5 (5) shows one of the audio signals converted into an analog waveform.
Taking the field as a unit section, it is further expanded by 5 times according to the reproduction speed ratio of 115 times according to the time axis with -, and the unit section is output as 115 times (evenly as shown). then 1
This is a case where the unit interval is made to correspond to the expansion of the time axis due to 159 times of reproduction.

Similarly, the other aspects are the same as in the previous two embodiments.

In the above embodiment, the output is based on the audio signal for one field, which is expected to have a track exogenous state of φ based on the CTL decoding.

It is also possible to compare the audio signals of each field that are successively reproduced, select the reproduction state, and output the audio signal based on that selection. Although the present embodiment has been explained based on 1/S speed playback, the present invention is not capable of 175 times speed playback. In addition, in the above-mentioned example, the tape excess was simply reduced to F. As explained in the low-level playback section, the low continuous 11L playback method uses intermittent playback method, which performs stealth playback and normal hidden playback alternately to eliminate band noise for head scan raw 1Iil. The head has two closely spaced gaps with different azimuths, and the alignment between the head and track is improved! A low-speed playback method using a tough azimuth head that increases the ratio of matching.

Low speed [playback method] using 4 heads per rotation at 906 intervals.

The present invention can also be applied to a low-stagger f-reproduction method using a dynamic tracking head in which a rotating head is attached to an electro-mechanical transducer such as a bimorph plate to control the reproduction scanning locus. .

In the audio signal reproducing apparatus of the present invention, a tape on which a video AM code and an encoded audio signal are time-divisionally recorded on a track formed by helical scanning is used. When reproducing, the unit section played from one track (for example, a
: 1 field) is stored in the storage means, and the time axis is enlarged according to the low m/o ratio, and the audio signal is successively transmitted over the period of time to be transmitted to the next lead position section to obtain a reproduction monitor sound. This is the next thing.

Therefore, it is possible to obtain a clear playback monitor sound with a time axis corresponding to the low speed ratio by using the best of the playback audio signals obtained by scanning the same track multiple times during low speed playback. can.

[Brief explanation of drawings]

Figures #11 and #2 are schematic diagrams of the rotary dome section of a helical scan VTR using the nine overscan system, and the reproduction system, in which the present invention is applied to the reproduction system, which is an embodiment of the audio signal reproduction device of the present invention. block circuit diagram. Fig. 116 is a time chart of the audio signal when the present invention is applied to the 1A double bending time.
(B) is another example of the present invention, and is a time chart of the audio signal when it is used during 14-note speed playback. Please refer to the symbols used in the drawings. (2)・・・・・・・・・Magnetic tape QaQI・
・・・・・・・・・Rum MllIJ・・・・・・・・・・・・This is Seimiku.

Claims (1)

[Claims] An audio signal reproducing device that reproduces and outputs an audio signal that has been time-base compressed and encoded by time division with a video signal on diagonal tracks formed by helical scanning on a magnetic tape, It should be played back from
A reproduction monitor sound is obtained by sequentially outputting audio signals of a unit section played from one track and stored in the storage means over a period corresponding to the unit section whose time axis is expanded according to a low crawl rate. An audio signal reproducing device comprising: