JPH02266777A - Video signal reproducing device - Google Patents

Abstract

PURPOSE:To display characters in such position at the time of normal reproducing that they can be easily seen by users and do not hinder a reproduced picture and to display them in such position at the time of variable speed reproducing that they can be easily seen by displaying characters in a position other than noise bars at the time of variable speed reproducing. CONSTITUTION:A display signal corresponding to the set mode or various operation modes is generated from a character generator 56, and this signal is superposed on a reproduced luminance signal Y by an adder 54 and is taken out from an output terminal 55. A controller 25 switches the character display position between normal reproducing and picture search, and the character display position is moved to a position free from noise bars at the time of picture search. Thus, characters are displayed in such position at the time of normal reproducing that they can be easily seen by users and do not hinder the reproduced picture, and characters are displayed in such position at the time of picture search that they can be easily seen.

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to a video signal reproducing device, and in particular to a video signal reproducing device.
Relates to character display during variable speed playback of TR.

[Summary of the invention]

In a video signal reproducing device, the character signal is displayed at a position other than the noise bar during variable speed playback, so that the character can be displayed even during variable speed playback, and the display can be easily seen during normal playback. It was made possible to do so.

[Conventional technology]

In recent VTRs, various operating states and warnings are displayed as characters on the playback screen so that the user can understand the operating states and warnings at a glance. In recent years, the number of character display items on playback screens has been increasing. In particular, in a camera-integrated VTR, the number of character display items is significantly larger than in a normal stationary VTR.

That is, in a normal stationary VTR, the setting status of operation modes such as recording, playback, fast forward, and rewind, a tape counter, remaining amount of tape, etc. are displayed in characters on the playback screen. In addition to this, in a camera-type VTR, the auto iris setting status, title, remaining battery level, date, etc. are displayed in characters.

It is desirable that the display positions of the various characters on the playback screen be such that the user can easily see them and that they do not interfere with the playback screen. Therefore, conventionally, the display position, which is most easily seen during normal playback and does not interfere with both sides of the playback, has been eliminated.
Ru.

[Problem to be solved by the invention]

However, in a VTR, the head passes through a plurality of racks during picture-to-picture, so noise bars occur. Characters cannot be displayed at the position of this noise bar.

Therefore, when displaying characters on the screen, the position of the noise bar must be avoided.

However, since there are a large number of display items, especially in a VTR with an integrated camera, if the position of the noise bar is avoided, the characters cannot be displayed in a position that is easy for the user to see during normal playback and does not interfere with the playback screen.

Therefore, an object of the present invention is to display a character in a position that is easy for the user to see during normal playback and does not interfere with the playback screen, and to display the character in a position that is easy to see during variable speed playback. is a video signal playback device that displays characters at positions other than the noise bar during variable speed playback.

[Function] On the screen, playback, rewind, and fast forward operations are displayed 71, a tape counter display 72, an index display 73 for cueing, an index mark display 74, and a recording date display 75. , Show 1/B1/I/Long Blaze Mort display 76, Auto iris display 77, Remaining tape warning display 78, Title display 79, Fader display 80,
A large number of displays, such as a battery remaining warning display 81, are displayed.

During normal playback, these displays 71 to 81 are displayed at positions that are easy for the user to see and do not interfere with the playback screen. At the time of picture search, the display positions of the displays 71-81 are switched so that the displays 71--81 are not at the position of the noise bar.

[Example] An example of the present invention will be described in the following order.

a. Recording system configuration b7 Explanation of high band mode and normal modeC. Explanation of Table Kai 5 1. d. Configuration of reproduction system C. Example 6 Character display a. Configuration of Recording System FIG. 1 shows the overall configuration of an embodiment of the present invention. In one embodiment of the present invention, in addition to the normal mode, it is possible to set a high band mode in which the carrier frequency is set high when FM modulating the luminance signal.

First, the configuration of the recording system will be explained. During recording, the switch circuit 16 is switched to the a side.

In FIG. 1, the imaging output of the CCD imaging device 1 is supplied to the process circuit 3 via the pre-amplifier 2. and (BY) are formed.

The luminance signal Y from the process circuit 3 is supplied to the FM modulation circuit 5 via the pre-emphasis circuit 4. Color difference signal (R-Y) and (B-¥) from process circuit 3
is supplied to the chroma modulation circuit 6.

The FM modulation circuit 5 performs FM modulation on the luminance signal Y. The carrier frequency at this time is switched depending on whether the normal mode is set or the high band mode is set. When the normal mode is set, the carrier wave frequency is, for example, 4.2 MHz at the sync chip level, and 5.4 MHz at the white peak level. When the high band mode is set, the carrier wave frequency is, for example, 5.7 MHz at the sync tip level and 7.7 MHz at the vomit beak level.

The output of the FM modulation circuit 5 is supplied to a half trap circuit 7. The half-trap circuit 7 is provided to prevent sideband components from interfering with the FM modulated audio signal Ay,1 and the low frequency converted chroma signal CA. The characteristics of the half trap circuit 7 are set according to the tape type and recording mode by a normal mode/high band mode and tape type MP/ME switching signal S2 from the controller 25. The output of the half trap circuit 7 is supplied to the adder circuit 8.

The chroma modulation circuit 6 receives the color difference signal (
From R-Y) and (B-Y), the low frequency converted chroma signal CA
is formed. The center frequency of this low frequency converted chroma signal CA is, for example, 743 kHz. The low frequency converted chroma signal CA from the chroma modulation circuit 6 is supplied to the adder circuit 8 .

An audio signal from the microphone 11 is supplied to a pre-emphasis circuit 13 via an amplifier 12. The output of the pre-emphasis circuit 13 is the audio FM modulation circuit 1
4. The audio FM modulation circuit 14 performs FM modulation on the audio signal. The center frequency of this FM modulated audio signal AFM is, for example, 1.5 MHz. The output of this audio FM modulation circuit 14 is
supplied to

The adder circuit 8 frequency-division multiplexes the FM modulated luminance signal Y□, the low-frequency converted chroma signal CA, and the FM modulated audio signal AFM. This multiplexed signal is sent to the recording amplifier 1.
5 to the a input terminals of the switch circuit 16.

The switch circuit 16 is switched to the a side during recording. The output of the switch circuit 16 is supplied to a switch circuit 17 for head switching. The switch circuit 17 includes
A head switching signal RFSW is supplied from the terminal 19. This head switching signal RFSW causes the switch circuit 17 to switch for each field. The output of the switch circuit 17 is supplied to rotary heads 18A and 18B disposed on the rotary drum 20.

The rotating drum 20 is provided with rotating heads 18A and 18B as well as a flying erase head 21. An erase current is supplied to the flying erase head 21 from a flying erase signal oscillation circuit 28 . The frequency of this erase current is
Normal mode/high band mode switching signal S from 5.

The mode can be switched depending on whether the mode is normal mode or high band mode.

A tape 22 pulled out from a tape cassette is wound around the rotating drum 20. The operation mode is set by operating the key switch 27. The capstan motor 23 is driven according to this operating mode.

b. Description of high band mode and normal mode As described above, in one embodiment of the present invention, a high band mode and a normal mode can be set.

Figure 2A shows the spectrum of the recording signal when recording in normal mode on an 8mm VTR, and Figure 2B shows the spectrum of the recording signal when recording in highband mode on an 8mm VTR. . In FIG. 2, Yrx is an FM-modulated luminance signal, CA is a low-frequency converted chroma signal, A1.4 is an FM-modulated audio signal, and P is a spectrum of a pilot signal for racking (ATF).

As shown in FIG. 2A, the carrier wave frequency of the FM modulated luminance signal Y is such that, in the normal mode, the sync tip level has a frequency of 4.2 MHz, and the white peak level has a frequency of 5.4 MHz. In the high band mode, as shown in FIG. 2B, the sync chimp level is 5.
7M&, the white peak level has a frequency of 7.7MHz.

The center frequency of the low frequency converted chroma signal CA is 743 kHz, and the center frequency of the FM modulated audio signal AF,1 is 1.5M7.

C. Description of tape cassette A tape cassette used in an embodiment of the present invention will now be described.

FIG. 3 shows an example of a chip cassette used in an embodiment of the present invention. The types of tapes are MP tape tape cassettes for normal mode (hereinafter referred to as normal MP tape cassettes), and MP tape tape cassettes for high band use (hereinafter referred to as high-M tape cassettes).
(abbreviated as P tape cassette) and ME for high band.
There are three types of tape cassettes (hereinafter abbreviated as high-ME tape cassettes).

Note that MP tape (coated metal tape) is made by applying ultrafine particles of an alloy of iron, nickel, and cobalt to a base material together with a binder. λ4P tape has excellent quality stability and M productivity. ME tape (vapor deposition tape) is made by evaporating an alloy containing cobalt and nickel in a vacuum and adhering it to a base material. M.E.
Although tape has higher performance than coated metal tape, it is difficult to turn it into an asset.

These three types of tape cassettes (normal MP tape cassette, high MP tape cassette, and high ME tape cassette) can be identified from the detection hole 64 and the state of the tape type detection 606.

That is, in FIG. 3, the bottom of the TV cassette includes a positioning six 63, a detection hole 64, and a detection hole 65 for preventing accidental erasure.
, a tape type detection hole 66, a positioning hole 67, a preliminary detection hole 08, and tape thickness detection holes 69 and 70 are formed.

The tape type detection hole 66 is provided to identify whether an ME tape or an MP tape is used. If this tape cassette uses ME tape, that is, a high ME tape cassette,
Tape type detection hole 6G is opened. If this tape cassette uses MP tape, ie, a normal MP tape cassette or a high MP tape cassette, the tape type detection hole 66 is closed.

The detection hole 64 is for high MP tape cassette or normal M.
It is provided to identify whether it is a P tape cassette.

If this tape cassette is a high MP tape cassette, the detection hole 64 is open. If this tape cassette is a normal MP tape cassette, the detection hole 64 is closed. Note that the detection hole 64 is also closed when the tape cassette is a high ME tape cassette.

Therefore, as shown in FIG. 4, three types of tape cassettes can be detected from the state of the detection hole 64 and tape type detection hole XX.

The states of the detection hole 64 and tape type detection hole 66 are detected by the tape hole detection means 24 in FIG. 1, and the detection output is supplied to the controller 25.

In one embodiment of the invention, a high band automatic recording mode can be set. This mode setting is performed by the key switch 26.

When the high band automatic recording mode is set, the 9L mode is automatically set according to the detected tape type. That is, if the tape type detection hole 6G is open and the detection hole 64 is closed, it is determined that the loaded tape cassette is a high ME tape cassette. In this case, recording is performed in high band mode. If the tape type detection hole 06 is closed and the detection hole 64 is open, it is determined that the loaded tape cassette is a high MP tape cassette. In this case, recording is performed in high band mode. If the tape type detection hole 06 is closed and the detection hole 64 is closed, it is determined that the loaded tape is a normal MP tape cassette. In this case, recording is performed in normal mode.

When the high band automatic recording mode is set to OFF, the normal mode is set regardless of the type of tape cassette installed. This makes it possible to set a recording state in which recording is performed in normal mode using a high ME tape cassette and a state in which recording is performed in normal mode using a high MP tape cassette.

A normal mode/high band mode switching signal S is output from the controller 25, and the characteristics of the pre-emphasis circuit 4 and the FM modulation circuit 5 are switched by this normal mode/high band mode switching signal S. Also, from the controller 25, the normal mode/
High band mode and tape type! An MP/ME switching signal S2 is output, and the characteristics of the half trap circuit 7 are switched by this normal mode/high band mode and tape type MP/ME switching signal St.

d. Configuration of playback system Next, the configuration of the reproduction system will be explained.

Recorded signals on the tape 22 are reproduced by the rotary heads 18A and 18B. The outputs of the rotary heads 18A and 18B are supplied to the switch circuit 16 via the switch circuit 17. During playback, the switch circuit 16 is switched to the b side. The output of the switch circuit 16 is supplied to the reproduction amplifier 31. The output of the playback amplifier 31 is a trap.
The signal is supplied to a peaking circuit 32 and also to a bandpass filter 33 and a bandpass filter 34 .

The bandpass filter 33 extracts the low frequency converted chroma signal CA from the reproduced signal. Bandpass filter 3
The low frequency converted chroma signal CA from 3 is supplied to the converter 35. The converter 35 removes time axis fluctuations from the reproduced signal and converts the reproduced low frequency converted chroma signal C.
a is converted into a chroma signal C having a frequency of 3°58 MHz. This chroma signal C is taken out from the output terminal 38.

The bandpass filter 34 extracts the FM modulated audio signal AFM from the reproduced signal. The FM modulated audio signal AFM from the bandpass filter 34 is supplied to an audio FM demodulation circuit 36. The audio FM demodulation circuit 36 performs FM demodulation on the reproduced FM modulated audio signal AFII. The demodulated audio signal A is taken out from the output terminal 39 via the de-emphasis circuit 37.

The FM modulated luminance signal YFM in the reproduced signal is supplied to the trap peaking circuit 32. The trap peaking circuit 32 removes unnecessary components and compensates for insufficient frequency components. The frequency characteristics (peak frequency and Q) of the trap/peaking circuit 32 are changed between the high band mode/normal mode and the tape type 1! by the normal mode/high band mode and tape type mMP/ME switching signal S4 from the controller 25. It can be switched depending on MP/ME.

The output of the trap peaking circuit 32 is supplied to an FM demodulation circuit 42 via an RFAGC circuit 40 and a soft limiter 41. At the same time, the output of the RFA''GC circuit 40 is transmitted to the mode discrimination circuit 43 and the dropout detection circuit 4.
4. The characteristics of the soft limiter 41 and the FM demodulation circuit 42 are switched depending on the high band mode and normal mode.

The mode determination circuit 43 detects the level of a predetermined frequency component in the reproduced FM modulated luminance signal Y□ and determines whether the signal reproduced from the tape 22 is a high band mode signal or a normal mode signal. be. In this example, the mode discrimination circuit 43 distinguishes between the frequency 4.2 MHz component and the frequency 9 component.
．． The 8 MHz component is detected, and the mode is determined as high band mode or normal mode.

In other words, in high band mode and normal mode,
The carrier wave frequencies used when FM modulating the luminance signal are different from each other. Therefore, by detecting the level of the frequency component concentrated in the high band mode recording signal or the frequency component concentrated in the normal mode recording signal and determining whether the level of this frequency component is higher than a predetermined value, it is possible to determine whether the high band mode is selected. It is possible to determine whether it is in normal mode.

However, when mode discrimination is performed by detecting the level of the frequency component concentrated in the high band mode recording signal or the frequency component concentrated in the dual mode recording signal, due to the influence of sideband components, The mode may be misidentified. For example, when recording in normal mode, a component with a frequency of 4.2 MHz, which is a frequency component concentrated in the recording signal, is detected, and this frequency component of 4.2 MHz is detected.
If a Hz component is detected, it is determined to be normal mode, and if a frequency component of 4°2 MHz is not detected, it is determined to be high band mode. If the sideband component of is 4.2M1(z), it is erroneously determined that the mode is normal mode.

Therefore, in one embodiment of the present invention, when recording in the normal mode mode, the frequency component concentrated in the recording signal is the frequency 4.2M1 (z component), and when recording in the high band, the lower side band is the frequency component concentrated in the recording signal. .2 MHz, the mode is determined by detecting the frequency component with a frequency of 9.8 Ml, which is the frequency at which the second side band should be ignored. Misjudgment of the mode due to the influence of is prevented.

However, such a mode discrimination circuit may incorrectly discriminate the mode when noise is generated, such as during variable speed playback, reverse L/rack playback, or the like.

That is, in a normal mode recording signal, if noise is generated during variable speed playback, reverse track playback, etc., a frequency component of 9° 8 MHz is detected due to the noise. Therefore, in such a case, a frequency component with a frequency of 4.2 MHz and a frequency component with a frequency of 9.8 MH2 are detected. When a frequency component with a frequency of 4°2M1 (z) and a frequency component with a frequency of 9°8MHz are detected, it is erroneously determined that the recording signal is in the high band mode even though the recording signal is in the normal mode.

Therefore, in one embodiment of the present invention, a dropout detection circuit 44 is provided, and this dropout detection circuit 44
The state of the mode discrimination circuit 43 is controlled by the output. That is, when dropout is detected by the dropout detection circuit 44, the state of the mode discrimination circuit 43 is held.

This makes it possible to avoid misjudgment of the mode during variable speed playback or reverse track playback.

The output of this mode discrimination circuit 43 is supplied to the controller 25. The controller 25 determines the mode of the recording signal on the tape 22 from the output of the mode determination circuit 43. Based on this mode discrimination result, 1 normal °L-
A high band/high band 7-mode switching signal S is formed. This normal mode/high band mode switching signal S switches the characteristics of the soft limiter 41, FM demodulation circuit 42, and de-emphasis circuit 45.

In the FM demodulation circuit 42, the reproduced FM modulated luminance signal Y,! , is FM demodulated. The reproduced luminance signal from the FM demodulation circuit 42 is sent to the switch circuit 46 via the de-emphasis circuit 45.
is supplied to b input terminals of. A grayback generation circuit 47 supplies grayback signals of a predetermined luminance level to a input terminals of the switch circuit 46 . A synchronization signal is added to the gray signal output from the grayback generation circuit 47.

Further, the output of the de-emphasis circuit 45 is supplied to a signal detection circuit 48 shown surrounded by a broken line. Signal detection circuit 4B
The presence or absence of a reproduced signal is detected.

Depending on the detection output of the signal detection circuit 48, the switch circuit 46 is switched and controlled.

When the signal detection circuit 48 detects the reproduced signal.

The switch circuit 46 is switched to the b side, and the demodulated reproduction signal is output from the switch circuit 46.

When the signal detection circuit 49 does not detect the reproduced signal, the switch circuit 46 is switched to the a side, and the reproduced signal is switched to a gray signal with a synchronizing signal.

As shown in item 2, by switching the playback signal to the G1/A signal with the synchronization signal, the synchronization deflection circuit of the monitor does not go into a free-run state, and the 71 displayed characters flow or the position of the displayed character. It can prevent things from going crazy.

The signal detection circuit 48 includes a synchronization separation circuit 50, a level detection circuit 51, a comparator 52, and a time constant circuit 53. A synchronization signal in the reproduced signal is detected by a synchronization separation circuit 50, and this synchronization signal 1/bell is detected by a level detection circuit 51. The output of this level detection circuit 51 is supplied to a comparator 52. The comparator 52 has two large and small
Two S1/Shield 1 novels ■t, ゎ□, and vchi are set.

The comparator 52 sets the synchronization signal level detected by the level detection circuit 51 to a predetermined threshold level v thn
and V, is detected. The output of the comparator 52 is supplied to the switch circuit 46 via a time constant circuit 53 as a switch control signal.

If there is a reproduced signal, the synchronization separation circuit 50 can separate the synchronization signal from the reproduced signal. Therefore, the level of the synchronization signal in the reproduced signal output from the level detection circuit 51 is within the two threshold levels v thH and VtkL set in the comparator 52 .

If there is no reproduced signal, the synchronization separation circuit 50 cannot separate the synchronization signal in the reproduction signal. Therefore, the level of the synchronization signal in the reproduction signal output from the level detection circuit 51 is set in the comparator 52. Two threshold levels, large and small, VthH and V, are no longer within.

If the output of the level detection circuit 51 is within the two threshold levels Vi and Vi set in the comparator 52, and it is determined that there is a reproduced signal, the switch circuit 46 switches to the b side. It will be done. If the output of the level detection circuit 51 is not within the two threshold levels VthH and VthL set in the comparator 52, and it is determined that there is no reproduced signal, the switch circuit 46 is switched to the a side.

Note that the time constant circuit 53 is provided to prevent the switch circuit 46 from being switched at the time of mode transition, thereby preventing the screen from becoming discontinuous. That is, when switching from normal playback to high-speed playback, for example, a synchronization signal in the playback signal cannot be obtained at the time of the mode transition. Therefore, the output of the level detection circuit 52 is sent directly to the comparator 5.
3, the delay back will be displayed for a moment at the time of mode transition, and then the playback screen will be displayed, breaking the continuity of the screen.

The time constant circuit 53 is supplied with the variable speed reproduction identification signal JOG from the controller 25 . This variable speed playback identification signal JO
G causes the time constant circuit 53 to operate, and the comparator 52
output is delayed. As a result, the detection sensitivity of the signal detection circuit 48 is lowered at the time of mode transition. By providing the time constant circuit 53 in this way, it is possible to prevent the continuity of the reproduced signal from being interrupted at the time of mode transition.

The output of the switch circuit 46 is taken out from an output terminal 55 via an adder circuit 54. Addition circuit 54 is supplied with a display signal from character generator 56 . The character generator 56 generates display signals according to setting modes and various operation modes. Addition circuit 54
Then, this display signal is superimposed on Y in the reproduced luminance signal. This reproduced signal Y is taken out from the output terminal 55.

e. Character Display in One Embodiment In one embodiment of the present invention, the display position of the character display is switched between during normal playback and during picture search. This results in
During normal playback, characters can be displayed in a position that is easy for the user to see but does not interfere with the playback screen, and
Characters can be displayed in easy-to-see positions even when searching for pictures.

That is, FIG. 5A shows the display position of the character display during normal playback, and FIG. 5B shows the display position of the character display during picture search.

On the screen, as shown in FIGS. 5A and 5B, an operation mode display 71 such as playback, rewind, and fast forward, a tape counter display 72, an index display 73 for cueing, an index mark display 74, Recording date display 75, short play/long play mode display 76, auto iris display 77, remaining tape warning display 78, title display 7
9. Fader display 80, battery level warning display 81
etc., many displays are made.

During normal playback, as shown in FIG. 5A, these displays 71 to 81 are displayed at positions that are easiest to see and do not obstruct the screen. By the way, during variable speed reproduction, noise bars N1, N2, and N3 occur as shown in FIG. 5B. As shown in FIG. 5A, the tape counter display 72 and fader display 80 are on the noise bar N1 during picture search, and the tape remaining amount warning display 78 and battery remaining amount warning display 81 are on the noise bar N2 during picture search. Be on top. Therefore, as is, all the displays 71 to 81 cannot be displayed on the screen during picture search.

Therefore, during a picture search, the display positions of the displays 71-8I are switched as shown in FIG. 5B. That is, during normal playback (to Fig. 5), the operation mode display 71, which was located above the position corresponding to the noise bar N1, and the short 1 noise/long 1/imode display 7
6. The title display 79 is moved below the position of the noise bar N1 during picture search. 6. The tape counter display 72 and fader display 80 are located above the position corresponding to the noise bar N1 during normal playback. The fader display 80 is moved below the noise bar N1 during picture search. will be moved to During normal playback, the position corresponding to noise bar N1 and noise bar N
The index display 73 and the mark display 74, which were located between the position corresponding to the noise bar N2, are moved below the noise bar N2.

During normal playback, the remaining TV cover display 7B and remaining battery level display 81, which are located above the position corresponding to the noise bar N2, are moved below the noise bar N2 during picture search.

Note that in the above-mentioned embodiment, the displays 71 to 8 during normal playback
1 display position and display 71 to 8 during picture search
The display position of 2 is predetermined, and the display position is projected at the predetermined position depending on the setting mode. However, during picture search, the position of the noise bar is determined using the dropout detection signal and ATF error signal. may be detected, and the display positions of the displays 71 to 81 may be determined so as to avoid the position of the noise bar during picture search.

〔Effect of the invention〕

According to this invention, the character display position is switched between normal playback and picture search, and during picture search, the character display is moved to a position where there is no noise bar. As a result, the character can be displayed in a position that is easy for the user to see during normal playback and does not interfere with the playback screen, and it is also possible to display the character in a position that is easy to see during picture search.

[Brief explanation of drawings]

FIG. 1 is a block diagram of an embodiment of this invention, FIGS. 2A and 2B are spectrum diagrams used to explain normal mode and high band mode, and FIG. 3 is a spectrum diagram used in an embodiment of this invention. A bottom view of an example of a tape cassette,
FIG. 4 is a route map used to explain an example of a tape cassette used in an embodiment of the present invention, and FIGS. 5A and 5B are route maps used to explain an embodiment of the present invention. Ichita, 71-81: Display.

Claims (1)

[Claims] A video signal playback device that displays characters at positions other than the noise bar during variable speed playback.