JPH04170292A - Magnetic recorder - Google Patents

Abstract

PURPOSE:To prevent increase in color slurring of a reproduced picture by acting a vertical filter function in the normal recording mode and bypassing the vertical filter processing in the dubbing or edit mode. CONSTITUTION:A switch circuit 111 outputs a signal from a contact N connected to an output of a coefficient multiplier circuit 110 in the usual recording mode. On the other hand, a signal from a contact E connected to a 1H line memory 109 not subjected to vertical filtering is outputted in the dubbing or edit mode. Thus, in this case, deterioration in a recording signal having been occurred in a conventional recorder due to passing through a vertical filter circuit 10A is not caused.

Description

[Detailed Description of the Invention] (Industrial Application Field) The present invention relates to a magnetic recording/reproducing device such as a video tape recorder, and in particular, to a magnetic recording/reproducing device such as a video tape recorder. The present invention relates to a magnetic recording device that does not cause color staining in reproduced images.

[Conventional technology]

Examples of the magnetic recording device of the present invention are shown in FIGS. 1(a) and 1(b).
) shows the configuration of the recording system REC of a high-definition VTR (HDVTR,) device and the corresponding regenerated yarn PB.

The operation of the recording system REC of the HD VTR device shown in FIG. 1(a) will be described.

The baseband recording luminance signal Y is converted into a digital signal by an analog/digital signal converter (ADC) 1 at a predetermined sampling clock, and is selectively switched by a switch circuit 4 to extend the time axis by one time, and is converted to a time axis extension circuit. 7.8, the time axis is expanded. Further, the recording color difference signals PR and PR of the 5 basebands are converted into digital signals by the ADCs 2 and 3 at a predetermined sampling clock, and the signals are inverted by the signal inverting circuits 5 and 6, and then the 5 color difference line sequential signal processing circuit 10 outputs the lines as described below. The signals are sequentially subjected to vertical filtering processing and further time-axis compressed by one-time axis compression circuits 11 and 12.

A recording luminance signal Y that has been subjected to time axis expansion processing and a recording color difference signal P that has undergone line sequential processing and time axis compression processing [1,
P++ is shuffled in the frame memory 14 and the three luminance signals and color difference signals are integrated into channel A;
A video recording signal in the TDM signal format of B is generated. The synchronization signal S\NC and burst signal BUR3T from the synchronization signal generation circuit 15 are added to the channel video recording signal in the form of a TDM signal in the signal addition circuit 16-17, and a digital/analog signal conversion circuit (DAC) is added.
The signals are converted into analog signals at steps 18 and 19, and recorded on the magnetic tape 25 via analog signal processing circuits 20 and 21 and the recording head 23. Analog signal processing circuit 20.2
1 is low-pass filtering, emphasis processing, FM
Performs modulation, etc.

The operation of the reproducing system PB of the D VTR device shown in FIG.

The video signal recorded on the magnetic head 125 is transferred to the reproduction head 30.
The signal is read out and applied to the analog signal processing circuits 32 and 33 via the switch circuit 31.

The analog signal processing circuit 32.33 performs the reverse operation of the analog signal processing circuit 20.21 in the recording system REC, such as FM demodulation and emphasis processing. The outputs of the analog signal processing circuits 32 and 33 are converted into digital signals by ADCs 34 and 35.

Deshuffling processing, which is the opposite of the shuffling processing of the frame memory 14, is performed in the frame memory 36.

The luminance signal from the frame memory 36 is transmitted to the time axis compression circuit 3.
Time axis compression processing was performed in 7.38.

One of the time axis compression processed signals is IH delayed by the L/H signal delay circuit 39 and sent to the time axis compression circuit 37 by the 1 switch circuit 40.
The signal from the IH signal delay circuit 39 and the signal from the IH signal delay circuit 39 are switched, and the DAC 50 generates a reproduction luminance signal Y corresponding to the recording luminance signal Y. The color difference signal from the frame memory 36 is subjected to time axis expansion processing in three time axis expansion circuits 42 and 43, one of the time axis expansion processed signals is further delayed in an IH signal delay circuit 44, and these signals are sent to a switch circuit 45.
is switched and applied to the one color difference line sequential signal interpolation circuit 46,
The signal is inverted by the signal inverting circuits 47 and 48, and the DAC 51~
52 is converted into an analog signal and is used as a color difference signal Pn for recording.
, PR are reproduced.

FIG. 3 shows a conventional circuit configuration of the color difference line sequential signal processing circuit 10 shown in FIG. 1(a). The third color difference line sequential signal processing circuit 10 includes latch circuits 101, 102. Switch circuit 103. and a 2H line memory 105 and a signal addition circuit 106.1 that constitute the vertical filter circuit 10A.
Coefficient multiplier circuit 107 for multiplying by a coefficient of /2. A signal addition circuit 108, an IH line memory 109, and a coefficient multiplication circuit 110 for multiplying by a 1/2 coefficient are configured as shown. The other circuit 10C has the same circuit configuration as described above, and operates in the same manner as the above circuit except that the operation timing of the Sui-7,000 circuit 103 is reversed.

FIG. 4 shows the form of signal processing carried out in each part of the color difference line sequential signal processing circuit 10 of FIG. Launch circuit 101, 10
Signal 5LOL from 2, 5102 is the switch circuit 103
The signal 5103.5 is switched alternately for each IH by
I04 is obtained.

In addition, in Fig. 4, the symbol ``r41B'' is 4.
The IH-th color difference signal PE and '41RJ indicate the 41H-th color difference signal PR.

These alternately switched color difference signals PR, PR are sent to the 2H line memory 105 and I which constitute the vertical filter circuit.
It is stored in H line memory 109. This vertical filter circuit 10A filters vertical color difference signals of horizontal lines above and below the color difference signal of a horizontal line (referred to as a reference line) from the LH line memory 109. That is, the color difference signal of the horizontal line below the reference line and the color difference signal of the horizontal line above the reference line from the 2H line memory 105 are multiplied by the signal addition circuit 106, and the 7 coefficient multiplication circuit 107 is multiplied by 1/ 2
The color difference signal of the reference line from the IH line memory 109 is added to this signal in the signal JJII calculation circuit 108, and the signal is halved in the coefficient multiplication circuit 110. -6~ signals 5103, 5104, 5ILO obtained by the above signal processing are shown in FIG. Signal Sl 10 represents the line-sequentially vertically filtered signal. For example, vertical filtering signal 43B'
is calculated as follows.

43B' - ((42R+44R)/2+43B)/2 The signal subjected to line-sequential vertical filtering in this manner is sent to the time-base compression circuit 11. Time axis compression processing is performed in I2, shuffled in frame memory 14, and F
The signal is M-modulated and recorded on the magnetic tape 25.

The color difference line sequential signal interpolation circuit 46 in the reproduction system PB of the HDVTR device shown in FIG. 1(b) has an inverse circuit configuration to the color difference line sequential signal processing circuit 10 as shown in FIG. That is, the two-color difference line sequential signal interpolation circuit 46 includes a one line memory 46L21 line memory 462 constituting the interpolation filter circuit 46A, a signal addition circuit 463, and a coefficient multiplication circuit 464 for multiplying by a 1/2 coefficient. Furthermore, switch circuit 4
65 are connected as shown in the figure. The interpolation filter circuit 46A has an inverse circuit configuration of the vertical filter circuit described above.

FIG. 6 shows the signal format in FIG. 5. The signal S45 that has been subjected to time axis expansion processing and switched by the switch circuit 45 is IH
The IH-delayed signal 3461 is outputted from the line memory 461 to the switch circuit 4651 as a signal 3461. Also signal S45
is added to the signal delayed by 2H in the 2H line memory 462 in the signal jlII calculation circuit 463, halved in the coefficient multiplication circuit 464, and output as a signal 3464 to the switch circuit 465. These signals are sent to the switch circuit 46
5 to obtain interpolated signals 3465 and 5466. B'' and R'' indicate signals obtained by further interpolating the vertical filtering signals B' and R' recorded on the magnetic tape.

FIG. 7 shows the signal form of the recording/reproducing process described above.

As shown in Figure 7(a), the color difference signal pH with an amplitude of 100%
, P is applied to the recording system RIE', C, the signal band becomes I as shown in FIG.
H spreads and the amplitude decreases accordingly. The signal recorded on the magnetic tape 25 in FIG.
The color difference signals P, , Pya are reproduced in the signal format shown in FIG. That is, by passing through the interpolation filter circuit of the two-color difference line sequential signal interpolation circuit 46, the respective bands of the color difference signals Pt+ and P+ are further broadened, and their amplitudes are reduced.

In FIG. 7, 'C☆ indicates an interpolated signal obtained from the preceding and succeeding lines.

[Problem to be solved by the invention]

When a video signal that has been recorded is repeatedly edited and dubbed using an HD VTR device that performs signal processing as described above, the recorded video signal deteriorates.

There is a problem in that the colors of the reproduced image accumulate.

For example, from a magnetic tape recorded by the above process, H.
When dubbing using a DVTR device, HDVTR
The apparatus reproduces the color difference signal shown in FIG. 7(C), and records it on a magnetic tape in the recording system REC based on this color difference signal. This recording signal has the signal form shown in FIG. 7d). That is, when dubbing, passing the recording system RPC through the vertical filter circuit again causes further waveform deterioration as shown in FIG. 7(d), and when this is reproduced, further deterioration occurs as shown in FIG. 7(e). The reproduced color difference signal PIl.

It becomes PR. In other words, the band of the recorded video signal further expands and the amplitude decreases accordingly. As a result, color fringing in the reproduced video image becomes large.

If such dubbing or editing is repeated, the deterioration of the recorded video signal increases and the color blur in the reproduced image increases.

Although the HDVTR device has been exemplified above, similar problems occur in ordinary video tape recorders and devices that perform filtering processing on their isthmus image signals to record and reproduce them.

Therefore, it is an object of the present invention to solve the above problems with a simple circuit configuration.

IO- [Means for solving the problems] In order to solve the above problems, the present invention performs filter processing on color signals in a direction perpendicular to a plurality of horizontal scanning lines,
A magnetic recording device that compresses the time axis and records on a recording medium together with a luminance signal is provided with selection means for selecting a first recording mode or a second recording mode.

[Operation] In the first recording mode, which is a normal recording mode, the vertical filter function is activated to perform a normal recording operation.

On the other hand, in the second recording mode, which is a mode for dubbing or editing, the vertical filter processing is bypassed. In this second recording mode, the filtering process 6 does not cause any new recording signal deterioration, so
The above-mentioned increase in color fringing in the reproduced image does not occur.

〔Example〕

2. As an embodiment of the magnetic recording device of the Niki invention, the dual HD VTR device of FIG. 1 is illustrated.

In the present invention, the color difference line sequential signal processing circuit 1 shown in FIG.
0 is configured as shown in FIG.

The circuit shown in FIG. 2 has a switch circuit 111 added to the conventional color difference line sequential signal processing circuit 10 shown in FIG. The switch circuit 111 switches the signal 5110 of the coefficient multiplication circuit 110 of the vertical filter circuit or the signal 5109 from the IH line memory 109. In normal recording mode, the switch circuit 111 is connected to the coefficient multiplication circuit 11.
Output the signal from contact N connected to the output of 0.

In dubbing or editing mode, a signal is output from contact E connected to IH line memory 109.

Signal processing in normal recording mode has been improved.

In edit mode, the vertically unfiltered I
A signal from H line memory 109 is output. Therefore, in case 2, the conventional recording signal does not deteriorate due to passing through the vertical filter circuit 10A. Note that since the reproduced color difference signal has already been vertically filtered,
The circuit 10C, which does not need to perform vertical filtering in the editing mode, is the same as described in "-" except that the switch circuit 111 operates in reverse.

Note that as a method of bypassing this vertical filtering process, the IH line memory 109 itself may be bypassed, as shown by the broken line in FIG.

Note that since two consecutive vertical filtering processes are not performed for the luminance signal 'YJ', the above-mentioned signal deterioration does not occur and bypass processing is not necessary.

Although the vertical filtering process for three lines in the horizontal force direction has been described above, the present invention can be applied to vertical filtering process for a plurality of horizontal lines.

In addition, although the HD VTR device was illustrated, the present invention has two advantages.
The present invention can be applied in the same manner as described above to an apparatus that performs line-sequential filtering processing on a plurality of color signals such as different color difference signals.

〔Effect of the invention〕

As described above, according to one aspect of the present invention, it is possible to provide a magnetic recording device with a simple circuit configuration in which recording signal deterioration does not increase even when editing or dubbing is performed multiple times. As a result, there is no increase in color blotches in the reproduced image.

[Brief explanation of the drawing]

FIGS. 1(a) and 1(b) show the HDVT of the embodiment of the present invention.
The configuration diagram of the R device. FIG. 2 is a vertical filter circuit diagram according to an embodiment of the present invention, and FIG. 3 is a conventional vertical filter circuit diagram. FIG. 4 is a signal processing configuration diagram according to FIG. 3. FIG. 5 is an interpolation filter circuit diagram in FIG. 1. FIG. 6 is a diagram showing the form of signal processing by the interpolation filter circuit of FIG. FIGS. 7(a) to 7(d) are diagrams showing conventional signal processing forms. (Explanation of symbols) 7.8... Time axis expansion circuit. 10... Color difference line sequential signal processing circuit. 11.12...Time axis compression circuit. 14. ・Frame memory. 20,. 21...Analog signal processing circuit. 32.33...Analog signal processing circuit. 36 - Frame memory. 37.38...Time axis compression circuit 3 42,/13...Time axis expansion circuit. 46... Color difference line sequential signal interpolation circuit.

Claims (1)

[Claims] 1. In a magnetic recording device that performs filter processing on a color signal in a direction perpendicular to a plurality of horizontal scanning lines, compresses the time axis, and records the same on a recording medium together with a luminance signal, the recording mode selection means comprises: A magnetic recording device characterized in that the magnetic recording device is configured to perform the filtering process in a first recording mode and bypass the filtering process in a second recording mode.