JPH05183864A - Video signal recording and reproducing device - Google Patents

Abstract

PURPOSE:To efficiently record and reproduce a telecine video signal which is generated on a 2-3 pull-down basis. CONSTITUTION:An input video signal Vin is supplied to a memory 5. A detecting circuit 7 for a telecine video signal detects whether or not the video signal Vin is the telecine video signal generated on the 2-3 pull-down basis. A recording control part 6 controls the reading and writing of the memory 5 according to the detection signal SDC from the detecting circuit 7. When the video signal Vin is said telecine video signal, the video signal Vin is recorded on a tape 4 while fields in telecine cycles No.3 and No.8 are omitted. When the signal is reproduced, the reproduced video signal is interpolated with video signals of said omitted fields and the original telecine video signal is outputted. The tape 4 is made to travel intermittently by controlling a capstan 10 at the time of the recording and reproduction. The recording and reproduction of the video signals of the overlapping fields are omitted, so the signal can be recorded on the tape with efficiency to save the tape 4.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION This invention is more than a motion picture film.
The present invention relates to a video signal recording / reproducing apparatus suitable for recording / reproducing a video signal formed by a -3 pulldown method.

[0002]

2. Description of the Related Art In the current television system (NTSC system), one frame is divided into two fields and transmitted by interlaced scanning, and the number of images is 30 frames (60 fields) per second. On the other hand, 16mm and 35
A standard motion picture film such as mm has 24 frames per second. As a method of forming a video signal (telecine video signal) from this motion picture film, the 2-3 pull-down method is conventionally known.

In the 2-3 pull-down system, the nth film is frame-fed every 3 fields (3/60 seconds), and the n + 1th film is frame-fed every 2 fields (2/60 seconds). , 2 frames of film and 5 fields of a video signal are associated with each other. Therefore, the telecine video signal formed by the 2-3 pull-down method is an alternating repetition of the video signal of 3 fields and the video signal of 2 fields formed from the same film.

For example, as shown in FIG. 1-3 fields are formed, and from the second frame, N
o. 4 and 5 fields are formed, and from the third frame, N
o. 6-8 fields are formed, and from the 4th frame, N
o. 9 and 10 fields are formed. Hereinafter, this is repeated.

[0005]

The telecine video signal formed by the 2-3 pull-down system has the No. of the above-mentioned 10-field cycle (hereinafter referred to as "telecine cycle").
1 and No. No. 3 field, no. 6 and No. The eight fields are the same (see FIG. 7). Therefore, recording and reproducing the telecine video signal formed by the 2-3 pull-down system as it is means recording and reproducing a redundant signal, resulting in wasteful consumption of the tape.

Therefore, an object of the present invention is to efficiently record and reproduce a telecine video signal formed by the 2-3 pulldown system.

[0007]

According to the present invention, there is provided a signal discriminating means for discriminating whether or not an input video signal is a telecine video signal formed by a 2-3 pull-down system from a motion picture film, and the input video signal. A signal recording / reproducing means for recording / reproducing, and when the signal discriminating means discriminates that the signal is a telecine video signal, the signal recording / reproducing means omits the recording of the overlapping fields of the input video signal at the time of recording, and The field omitted is interpolated in the reproduced video signal.

[0008]

The telecine video signal formed by the 2-3 pull-down system has the telecine cycle No. 1 as described above. 1 and N
o. No. 3 field, no. 6 and No. The eight fields are equal. In the above configuration, 2-3
When the telecine video signal formed by the pull-down method is recorded, the video signals of the overlapping fields (for example, No. 3 and No. 8) are omitted and recorded, and the video signals of the omitted fields are interpolated in the reproduced video signal during reproduction. To be done. Since the recording and reproducing of the video signals of the overlapping fields are omitted, it is possible to efficiently record the video signals on the recording medium.

[0009]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to the drawings.

In the figure, 1 is a rotary head device, 2 is a tape guide drum, and 3A and 3B are rotary magnetic heads. A magnetic tape 4 is obliquely wound around the tape guide drum 2 over an angular range of about 180 °.
The heads 3A and 3B are arranged at an angular interval of 180 ° with each other, and each head has a frame period (1 / SC in the NTSC system).
It is configured to rotate once in 30 seconds.

The video signal Vin supplied to the input terminal 4 is
It is supplied to the buffer memory 5 for data thinning.

The video signal V supplied to the input terminal 1
in is supplied to the recording control unit 6 including a sync separation circuit, a PLL circuit, and the like. In the recording control unit 6, the write control signal W, the read control signal R, etc. supplied to the buffer memory 5 are formed.

A video signal V supplied to the input terminal 4
in is supplied to a detection circuit 7 which detects a telecine video signal formed by a 2-3 pulldown system from a motion picture film. FIG. 2 shows a specific configuration of the detection circuit 7.

In the figure, the video signal Vin is directly supplied to the subtractor 11, and is also supplied to the subtractor 11 via the series circuit of the field memories 12 and 13 forming a delay circuit (delay time of one frame period). Then, the subtracter 11 outputs the one-frame difference signal SDF. A frame memory may be used instead of the field memories 3 and 4.

The difference signal SDF output from the subtractor 11 is
After the absolute value is taken by the absolute value circuit 14, it is supplied to the integrating circuit 15 and integrated. The integrated value in the integrating circuit 15 is reset at the rising edge of the field pulse VP. Here, the field pulse VP is supplied from the recording controller 6.

The integrated output from the integrating circuit 15 is supplied to the comparator 16 and compared with a predetermined threshold value Vth. The comparison output of the comparator 16 is “0” when the integrated output is smaller than the threshold Vth, and is “1” when the integrated output is equal to or larger than the threshold Vth.

The comparison output from the comparator 16 is supplied to a series circuit of registers (D flip-flops) 17-21. The field pulse VP is supplied to the registers 17 to 21 as a clock. Registers 17-21
Is supplied to the OR gate 22.

The output signal of the OR gate 22, the signal obtained by inverting the output signal of the register 21 by the inverter 23, and the output signal of the registers 17 to 20 are the AND gate 24.
And the output signal of the AND gate 24 is output as the detection signal SDC.

As described above, the telecine video signal formed by the 2-3 pull-down system has the telecine cycle No. 1
And No. No. 3 field, no. 6 and No. The eight fields are the same (see FIG. 7). Therefore, when the video signal Vin supplied to the input terminal 1 is a telecine video signal formed by the 2-3 pull-down method, No. In the fields 1 and 6, all the input signals of the AND gate 24 become "1", and the detection signal SDC from the AND gate 24 becomes "1" (shown in FIG. 3C). FIG. 3A shows the video signal Vin, and FIG. 3B shows the field pulse VP.

Returning to FIG. 1, the detection signal SDC output from the detection circuit 7 is supplied to the recording controller 6. The write control signal W and the read control signal R are output from the recording control unit 6 in accordance with the detection signal SDC and supplied to the buffer memory 5.

That is, when the detection signal SDC becomes "1" every 5 fields and the video signal Vin is the telecine video signal formed by the 2-3 pulldown system, the control signals W and R are No. 1 of the telecine cycle. 4-7, No. 9
Clock CK is output in the fields of ~ 2 (Fig. 3D).
(Illustrated in).

On the other hand, when the detection signal SDC remains "0" and the video signal Vin is a normal video signal, the clock CK is continuously applied in each field as the control signals W and R.
Is output.

The control signals W and R as described above are supplied to the buffer memory 5 from the recording controller 6. Therefore, when the video signal Vin is a telecine video signal formed by the 2-3 pulldown system, the buffer memory 5 stores the No. of the telecine cycle. 4-7, No. The video signals Vin of the fields 9 to 2 are sequentially written in synchronization with the clock CK, and the No. 4-7,
No. The video signal Vin of the fields 9 to 2 is clocked by the clock C.
It is sequentially read in synchronization with K.

In the reproducing system described later, the code signal SCD which becomes "1" in the field immediately before the omitted field.
No. of the telecine cycle so that Two
The code data DA is supplied from the recording controller 6 to the buffer memory 5 at the timing of the field 7 and the video signal V
Appended to in.

The video signal Vin added with the code data DA read from the buffer memory 5 is, for example, FM modulated by the modulation circuit 8, and then the head 3 is passed through the recording amplifier 9.
It is supplied to A and 3B as a recording signal. In FIG. 1, illustration of a rotary coil and the like is omitted.

Further, the recording controller 6 controls the rotation of the capstan 10 and the tape running. That is, when the video signal Vin is a telecine video signal formed by the 2-3 pull-down method, N of the telecine cycle is used.
o. 4-7, No. In the fields Nos. 9 and 2, the vehicle runs at normal speed. The driving is stopped in the fields 3 and 8 (shown in FIG. 3E). On the other hand, when the video signal Vin is the normal video signal, the vehicle travels at the normal speed through each field.

Therefore, when the video signal Vin is a telecine video signal formed by the 2-3 pulldown system,
No. of telecine cycle 4-7, No. A recording track T is formed on the magnetic tape 4 in the fields 9 to 2 and the video signal in that field is recorded (shown in FIG. 3F). FIG. 4B shows a recording track pattern.

On the other hand, when the video signal Vin is a normal video signal, the recording track T is formed on the magnetic tape 4 in each field, and the video signal of that field is recorded. FIG. 4A shows a recording track pattern.

The video signal reproduced by the heads 3A and 3B from the magnetic tape 4 is demodulated by the demodulation circuit 3 via the reproduction amplifier 31.
2 and is demodulated. The video signal VPL output from the demodulation circuit 32 is supplied to the 2-3 conversion circuit 33.

The video signal VPL output from the demodulation circuit 32 is supplied to the reproduction control section 34 having a sync separation circuit and a PLL circuit. The clock CK and the field pulse VP formed by the reproduction controller 34 are supplied to the 2-3 conversion circuit 33.

The video signal VPL output from the demodulation circuit 32 is also supplied to the code detection circuit 35. In the code detection circuit 35, based on the code data DA added and recorded to the video signal Vin in the recording system, the N of the telecine cycle is set.
o. A code signal SCD of "1" is obtained at the timing when the video signals of the fields 2 and 7 are reproduced. This code signal SCD is supplied to the reproduction control unit 34, and
Is supplied to the -3 conversion circuit 33.

The reproduction controller 34 controls the capstan 10
The rotation of the tape is controlled and the tape running is controlled. That is, the traveling is stopped in the field next to the field where the code signal SCD is obtained, and the traveling is performed at the normal speed in the other fields (FIG. 5).
(Shown in D).

Therefore, the video signal formed by the 2-3 pull-down method on the magnetic tape 4 has the telecine cycle No. 1 as described above. When the video signals of the fields of 3 and 8 are omitted and recorded, the No. 3 of the telecine cycle is recorded. 4-7,
No. The video signals of the corresponding fields in fields 9 to 2 are continuously reproduced (shown in FIG. 5A). B of the same figure shows the code signal SCD, and C of the same figure shows the field pulse VP.

On the other hand, when the normal video signal is recorded on the magnetic tape 4, since the code signal SCD of "1" cannot be obtained, the video signal of each field is continuously reproduced.

In the above-mentioned 2-3 conversion circuit 33, the video signal VPL output from the demodulation circuit 32 relates to the telecine video signal formed by the 2-3 pull-down system,
No. of telecine cycle When the video signals of the fields 3 and 8 are omitted, the video signals of the fields are interpolated.

FIG. 6 shows a specific structure of the 2-3 conversion circuit 33. In the figure, the video signal VPL output from the demodulation circuit 32 is supplied to the field memory 41 as a write signal and is also supplied to the fixed terminal on the a side of the changeover switch 42.

The code signal SCD output from the code detection circuit 35 is a register (D flip-flop) 4
It is supplied to the series circuit of 3-46. Registers 43-46
The field pulse VP is supplied as a clock to the. The output signals of the registers 43 and 46 are supplied to AND gates 47 and 48, respectively. These AND gates 4
A clock CK is supplied to each of 7 and 48.

Video signal VPL output from the demodulation circuit 32
Is related to the telecine video signal formed by the 2-3 pull-down method, and the telecine cycle No. When the video signals of fields 3 and 8 are omitted (shown in FIG. 5A), the telecine cycle No. A code signal SCD that becomes "1" in the fields 2 and 7 is obtained (shown in FIG. 9B). Therefore, the output signal of the register 43 is the No. of the telecine cycle. It becomes "1" in the fields of 3 and 8 (shown in FIG. 8E), and the output signal of the register 46 is No. of the telecine cycle. It becomes “1” in fields 1 and 6 (shown in FIG. 4F).

From the AND gate 48, the No. of the telecine cycle is set. The clock CK is gated and output in the fields 1 and 6 and is supplied to the field memory 41 as the write control signal W (illustrated in FIG. 5H). Further, from the AND gate 46, the telecine cycle No. Three
The clock CK is gated and output in the field of 8 and is supplied to the field memory 41 as the read control signal R (shown in G in the same figure).

As a result, the No. of the telecine cycle is set. 1,6
In each field, the video signal of that field is written in the field memory 41, and at the same time, No. Three
8 fields, N from field memory 41
o. The video signals of fields 1 and 6 are read out.

The video signal output from the field memory 41 is supplied to the fixed terminal on the b side of the changeover switch 42. The output signal of the register 43 is supplied to the changeover switch 42 as a control signal. The changeover switch 42 is connected to the a side when the output signal of the register 43 is “0”, and is connected to the b side when the output signal of the register 43 is “1”.

From the above, the video signal VPL output from the demodulation circuit 32 relates to the telecine video signal formed by the 2-3 pull-down system.
When the video signals of the fields of 3 and 8 are omitted (shown in FIG. 5A), No. Nos. 3 and 8 are stored in the field memory 41. Since the video signals of the fields 1 and 6 are read out and the changeover switch 42 is connected to the side b, the changeover switch 42 outputs No. Nos. 3 and 8 are respectively entered in the fields. 1,6
A video signal obtained by interpolating the video signal of the field is output (illustrated in FIG. 1I).

Originally, the telecine video signal formed by the 2-3 pull-down system is No. 1 and No. No. 3 field, no. 6 and No. The eight fields are the same (see FIG. 7). Therefore, the video signal interpolated as described above and output from the changeover switch 42 is
It is the same as the telecine video signal formed by the 2-3 pulldown system.

On the other hand, when the video signal VPL output from the demodulation circuit 32 is related to the normal video signal, the code detection circuit 35 cannot obtain the code signal SCD of "1". The video signal VPL is output as it is from the changeover switch 42.

Returning to FIG. 1, the video signal Vout output from the 2-3 conversion circuit 33 is led to the output terminal 36.

As described above, in this example, when the video signal Vin supplied to the input terminal 4 is a telecine video signal formed by the 2-3 pull-down system, fields that overlap during recording (for example, No. 3, No. 8) is omitted and recorded, and the video signal of the omitted field is interpolated to the reproduced video signal during reproduction. Therefore, since the recording / reproducing of the overlapping field is omitted, the video signal can be efficiently recorded on the magnetic tape 4, and the recording medium is not wastefully consumed.

In the above embodiment, the telecine cycle No. Recording and reproduction of video signals of fields 3 and 8 are omitted, but instead of No.
Recording and reproduction of video signals of fields 1 and 6 may be omitted.

Further, in the above embodiment, the detection circuit 7
Is configured by using five registers 17 to 21. By increasing the number of stages of the registers, it is possible to reduce the error that the "1" signal is output from the AND gate 24 in the normal video signal. You can

Further, although the above embodiment is applied to the VTR, the present invention can be applied to a disk recording / reproducing apparatus or the like as well.

[0050]

According to the present invention, when the telecine video signal formed by the 2-3 pull-down system is recorded, the video signals of the overlapping fields are omitted and recorded, and when reproduced, the video signals of the fields omitted in the reproduced video signal are recorded. The video signal is interpolated. Therefore, since the recording / reproducing of the video signals of the overlapping fields is omitted, the video signals can be efficiently recorded on the recording medium, and the recording medium can be saved.

[Brief description of drawings]

FIG. 1 is a block diagram showing a configuration of an embodiment.

FIG. 2 is a block diagram showing a detection circuit for a telecine video signal.

FIG. 3 is a time chart showing the operation of the recording system.

FIG. 4 is a diagram showing a recording track pattern.

FIG. 5 is a time chart showing the operation of the reproduction system.

FIG. 6 is a block diagram showing a 2-3 conversion circuit.

FIG. 7 is a diagram for explaining a 2-3 pulldown method.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 rotary head device 3A, 3B rotary magnetic head 4 input terminal 5 buffer memory 6 recording control unit 7 telecine video signal detection circuit 8 modulation circuit 10 capstan 32 demodulation circuit 33 2-3 conversion circuit 34 reproduction control unit 35 code detection circuit 36 output terminals

Claims (1)

[Claims] 1. The input video signal is 2-3 from a movie film.
It is provided with a signal discriminating means for discriminating whether or not the telecine video signal is formed by a pull-down system, and a signal recording / reproducing means for recording / reproducing the input video signal, wherein the signal discriminating means is the telecine video signal. When judged, the signal recording / reproducing means omits recording of the overlapping fields of the input video signal at the time of recording, and interpolates the omitted fields in the video signal reproduced at the time of reproduction. Signal recording / reproducing device.