CN1003696B - Carrier wave colour signal recording and reproducing device - Google Patents
Carrier wave colour signal recording and reproducing device Download PDFInfo
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- CN1003696B CN1003696B CN85107249.6A CN85107249A CN1003696B CN 1003696 B CN1003696 B CN 1003696B CN 85107249 A CN85107249 A CN 85107249A CN 1003696 B CN1003696 B CN 1003696B
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Abstract
The present invention relates to a device for recording and regeneration of a chromatic carrier signal, which is used for converting the chromatic carrier signal separated from a colour picture signal into a preset signal form in which the carrier chromatic signal is easy to record on a recording medium and obtaining a regenerated chromatic carrier signal in the original signal form from the replayed signal read from the recording medium during replay. The device comprises a recording system which is provided with a preemphasis circuit, and a replay system which is provided with a deemphasis circuit.
Description
The present invention relates to recording and reproducing device of a kind of subcarrier chrominance signal, particularly relate to recording and reproducing device of a kind of like this subcarrier chrominance signal, in this equipment, subcarrier chrominance signal is subjected to preemphasis, so that it is recorded on the magnetic recording medium, and at playback time, the subcarrier chrominance signal of playback is postemphasised, thereby along with the reduction of noise, the subcarrier chrominance signal of recovery-original playback.
Video tape recorder (VTR) or its similar record with reproducing device in, from the color picture signal that will be recorded and reset, tell luminance signal and subcarrier chrominance signal earlier.All must stand prearranged signal then handles.Afterwards, in order to record and to reset, these two signals are doubled.Conventional process is performed such sometimes, promptly reduces noise by the capable correlation that is similar to luminance signal in subcarrier chrominance signal.More particularly, the subcarrier chrominance signal of resetting generally has capable correlation, most of noises in the playback subcarrier chrominance signal are very for a short time to have a this journey correlation but sneak into, in view of this fact, input and output playback subcarrier chrominance signal is mixed in 1 row delay circuit, do not have the noise of this journey correlation in order to elimination, and noise is sneaked in the playback subcarrier chrominance signal, thereby reach out the playback subcarrier chrominance signal that noise has been reduced by amplitude limiter.
Yet record and reproducing device in the tradition with playback subcarrier chrominance signal noise reducing circuit, that be used for not going correlation, the signal component and the noise of correlation of going deducts from the playback subcarrier chrominance signal of input together.Therefore, just run into a problem, its vertical spatial frequency characteristic (vertical resolution) has degenerated.
In view of the foregoing, the applicant had proposed recording and reproducing device of a kind of subcarrier chrominance signal as shown in figure 13 in Japanese patent application NO.138872/83.In Figure 13, television system (NTSC in standard, it is the standard that national television system committee is determined, or PAL, be the standard of phase place line-by-line inversion) in, the color picture signal that enters input 1 is added on the low pass filter 2, thereby filters out luminance signal, be added to simultaneously on the band pass filter 3, thereby filter out carrier chrominance signal.Luminance signal is added to records on the luminance signal processing circuit 4, here, it is subjected to prearranged signal and handles for example frequency modulation(FM) (FM).On the other hand, subcarrier chrominance signal is added to preemphasis circuit 5.Here, each signal component in the delegation's scan period (1H) that on the vertical direction of frame, occurs, all be subjected to preemphasis, so that the subcarrier chrominance signal that it is provided with pre-emphasis characteristic, in the middle of this, radio-frequency component in its vertical direction spatial frequency, compare with low-frequency component, be relatively to have increased on level, after this, this signal be added to record on the subcarrier chrominance signal treatment circuit 6, here, this conversion of signals is become to be suitable for use as the prearranged signals form that magnetic is recorded and reset, for example, its frequency is reduced.Record on the amplifier 7 being converted into to be added to after the luminance signal of desired signal form and subcarrier chrominance signal are taken out, here, they are mixed mutually and amplifies, be recorded on the tape 9 by rotating write head then.
On the other hand, at playback time, the signal that is recorded on the tape 9 is reset by rotary playback head 10, the signal of this playback is added on high pass filter 12 and the low pass filter 13 through preamplifier 11.For example, the luminance signal of frequency modulation is leached by high pass filter 12.Be demodulated to luminance signal on its original frequency band by luminance signal playback treatment circuit 14 then.On the other hand, with converting low pass to and from replay signal, separating and filtering, then, subcarrier chrominance signal is added on the subcarrier chrominance signal playback treatment circuit 15 by the subcarrier chrominance signal of low pass filter 13 records.Here, it is resumed into the primary signal form, becomes the playback subcarrier chrominance signal.Should the playback subcarrier chrominance signal be added on the deaccentuator 16, make it the level nature of preemphasis circuit 5 on vertical spatial frequency had the characteristic of a complementation.This characteristic of postemphasising is such characteristic, and wherein, the HFS of vertical spatial frequency is compared with low frequency part, is relative attenuation on level.Therefore, the playback subcarrier chrominance signal of having accepted preemphasis reverts to the original waveform before being subjected to preemphasis and therefrom takes out in deaccentuator 16.Then it is added on the hybrid circuit 17, here, this signal with mix mutually from the playback luminance signal of luminance signal playback treatment circuit 14.Because, the playback color picture signal of a noise component that has reduced extracted from hybrid circuit delivers to output 18.
Because the level nature of vertical spatial frequency is subjected to postemphasising of deaccentuator 16, the signal to noise ratio in the subcarrier chrominance signal of playback can be improved.And because increasing the weight of the level nature that vertical spatial frequency is worsened, and by being preset in the record of the preemphasis circuit 5 in the recording system, so, what take out from output 18 is that a signal to noise ratio is improved, and the level nature of vertical spatial frequency does not become bad playback color picture signal.
In view of the foregoing, adjust the phase place of coefficient circuit 24 output signals by phase regulator 25, so that make said phase place consistent with the phase place of the subcarrier chrominance signal that accurately postpones delegation, thus obtain desired pre-emphasis characteristic.
The subcarrier chrominance signal that is added on the input 20 has a waveform shown in Figure 15 (A).In Figure 15 (A), time interval a
1The time interval of a vertical blanking of expression, time interval a
2Be a
1A part, at a
1A middle vertical sync pulse and the equivalent pulse in the vertical blanking time interval, the time interval a of existing
2Be a
1A part, at a
3Burst signal of middle existence.Time interval a
4Represent a vertical-scan period, have burst signal and subcarrier chrominance signal therein.To be shown in the radio-frequency component of its vertical spatial frequency of subcarrier chrominance signal among Figure 15 (A), with the low-frequency phase ratio, on level, increased by preemphasis circuit shown in Figure 14, therefore has the waveform shown in Figure 15 (B), then, this waveform is released on the terminal 28, under the situation of rotation dual-magnetic head type video tape recorder, in the subcarrier chrominance signal shown in Figure 15 (B), vertical blanking time at interval the first few lines of original position be shown in b
1The position on indicate a change point, before this change point and afterwards, the phase place of playback subcarrier chrominance signal is discontinuous.Here, with preemphasis circuit the time constant of vertical direction and level increase degree be established to one be with the numerical value that reduces noise on, the signal of previous field is influential to the beginning part of signal in the vertical-scan period after next field transformation point, disturbs thereby tone interference and amplitude occur on the top of playback frame; And, because distortion distortion has also changed the cycle of row.
In view of the foregoing, this other bright purpose provides recording and playback circuitry of a cover subcarrier chrominance signal, and this cover circuit has a kind of like this setting of difference to overcome above mentioned variety of issue by operating in of aforementioned preemphasis circuit and deaccentuator between vertical scanning period and the vertical blanking period.
Furthermore, the subcarrier chrominance signal that will be shown among Figure 16 (A) is added to input 20.And on the correlation that will be expert at, be high level, and among one in arbitrary line-scanning period the subcarrier chrominance signal just like waveform shown in Figure 16 (A) be added on the input 20.Near the middle part of frame, its waveform and the identical subcarrier chrominance signal of waveform shown in Figure 16 (A) for example, take out from output 28.Then, both made the input of this subcarrier chrominance signal, be high level in the correlation of being expert at, and the frequency characteristic of its 1 row delay circuit 23 is compared when being narrow with the frequency band of the subcarrier chrominance signal of input, so that its desired 1 row delay circuit 23 can't be provided, also will occur such as ambiguous distortion at the output of 1 row delay circuit 23.Like this, subcarrier chrominance signal with transient characteristic degraded signal waveform shown in Figure 16 (B) appears at the outlet terminal of subtraction circuit 21; And the subcarrier chrominance signal with overshoot shown in Figure 16 (C) and ring distortion takes out from subtraction circuit 21, is added on the output 28.Especially, distortion is along with the increase of coefficient circuit 24 coefficients like this, so that when improving signal to noise ratio (signal and noise ratio) and become bigger, this and the improvement degree positive lance value that improves signal to noise ratio.Particularly, in Figure 16 (A) to (C), be shown in the inconvenience that distortion in the burst signal of CB section will cause subcarrier chrominance signal treatment circuit (for example, automatic phase control (APC) circuit and autochroma control (ACC) circuit) operation.The amplitude of these circuit usefulness burst signals and phase place are as benchmark, and this just makes the quality of reproduced picture descend.
In addition, Figure 17 (A) illustrates one signal of preemphasis circuit 5 input subcarrier chrominance signals.For the purpose of illustrating, Figure 17 (A) illustrates the subcarrier chrominance signal of same degree of saturation.The burst signal of burst signal in the cycle among only during the return line deletion that will transmit is shown in the X among Figure 17 (A).In addition, subcarrier chrominance signal outside during vertical retrace line deletion is such signal, in these signals, with the burst signal in during the image and subcarrier chrominance signal (for ease of explanation, the colour signal that is referred to as to modulate), on time series, do alternately to synthesize.This is well-known.Yet, in Figure 17 (A), for the purpose of illustrating, only with the colour signal waveform of modulation, the y among the cycle beyond being expressed as during the vertical retrace line deletion continuously, and do not comprise wherein synchronizing signal.In fact, the colour signal of this modulation is an intermittent transmission, and for the ease of observing, the time shaft on the oscilloscope has been turned down, like this, these signals it seems just go up as y among Figure 17 (A) shown in, just like generally continuous.
When allowing the subcarrier chrominance signal shown in Figure 17 (A), on the amplitude of the burst signal X in several cycles of a beginning, for example, be big than near the burst signal the core of the frame shown in Figure 17 (B) by preemphasis circuit 5.This is because occurred subcarrier chrominance signal immediately before between non-transmission period, and the correlation of row.Recording in the treatment circuit 6 of subcarrier chrominance signal, the colour signal of this range value part and modulation is being suppressed to form shown in Figure 17 (C) by means of the ACC circuit before the transmission together.When this signal is introduced into deaccentuator 16, the colour signal of its burst signal and modulation begins can lose their complementary characteristic, its result between several departures date in the field of playback carrier chrominance signal, shown in Figure 17 (D), its amplitude amplitude when recording that will become.Therefore, show in the top of frame color thin out.
Therefore, further aim of the present invention provides recording of a kind of subcarrier chrominance signal and reproducing device, this equipment can overcome above resulting variety of issue, in the equipment of this equipment, make and between the transmission period of its burst signal, stop the operation of preemphasis and deaccentuator fully.
According to the present invention, this equipment comprises a recording system that preemphasis circuit is housed, in this preemphasis circuit, at least the level that comprises time constant on scheduled period in vertical blanking cycle or its time constant and vertical direction amplifies degree, and the two all is made into less than time constant and vertical direction level on during outside the above-mentioned scheduled period and amplifies degree, and the above-mentioned subcarrier chrominance signal that will provide, the radio-frequency component of its vertical spatial frequency, compare with low-frequency component, after relatively amplifying on the level, discharge again.This equipment comprises a playback system that deaccentuator is housed.This deaccentuator, in during above-mentioned scheduled period and other, to having a characteristic to serve as a contrast mutually on the characteristic during above-mentioned preemphasis circuit is during relevant each, the vertical high frequency composition of the subcarrier chrominance signal of Chong Fanging wherein, compare with low-frequency phase, relatively discharge again after the decay.
According to the present invention, this equipment also comprises a such recording system that the preemphasis electrode is housed.In this preemphasis circuit, add to subcarrier chrominance signal, for the subcarrier chrominance signal in during during the input of a burst signal, the radio-frequency component of its vertical spatial frequency, compare with low-frequency component, after relatively amplifying on the level, discharge again, and for burst signal, be to stop its operation fully.This equipment also comprises such playback system that deaccentuator is housed.In this deaccentuator, the playback subcarrier chrominance signal of recovering the primary signal form is added up, above-mentioned preemphasis circuit characteristic is done, the radio-frequency component and the low-frequency component of vertical spatial frequency are compared, on level, do the complementation of such specific character that relatively decays, playback subcarrier chrominance signal in during only giving during burst signal is done, and to this burst signal, this operation stops fully, be that burst signal is not subjected to preemphasis and postemphasises, specific embodiments of the present invention is described to Figure 12 below with reference to Fig. 1.
Fig. 1 illustrates according to equipment of the present invention, and the block diagram of first specific embodiments of preemphasis circuit in its recording system, Fig. 2 are according to equipment of the present invention, the block diagram of first specific embodiments of the deaccentuator in its playback system.Preemphasis circuit 5 in Figure 13 and deaccentuator 16 and the applicant propose record with reproducing device in preemphasis circuit different with deaccentuator, equipment of the present invention is similar with equipment shown in Figure 13 structurally.Among Fig. 1 with Figure 14 in identical part be marked with identical reference number, and no longer illustrated.The subcarrier chrominance signal that is delayed circuit 23 delay delegation is added to the 30a end of switching circuit 30.This subcarrier chrominance signal shifts out from the 30b end or the 30c end of switching circuit 30.The signal that shifts out from the 30b end is multiplied by a COEFFICIENT K coefficient circuit 24
1(for example 0.76); The signal that shifts out from the 30c end is multiplied by a COEFFICIENT K coefficient circuit 31
3(for example 0.56), the two is added on the phase regulator 25 simultaneously.
34 terminations are received a switching pulse shown in Figure 15 (D), and this pulse is that the rotation detection signal by a rotating cylinder forms, and such as have 50% duty ratio and 30 hertz frequency, and this pulse is added on the pulse generator 35.Pulse generator 35 detects the upper and lower of switching pulse, thereby removes to produce a vertical blanking pulse shown in Figure 15 (E), supposes a high level in the vertical blanking cycle here, and above-mentioned pulse is added on switching circuit 30 and 32. Switching circuit 30 and 32 is being connected respectively between the vertical blanking pulse low period on 30a and 30b and 32a and the 32b; Linking respectively between high period on 30a and 30c and 32a and the 32c.
Therefore, in vertical cycle, the weighting of subcarrier chrominance signal realizes by coefficient circuit 24 and 26, and the same with shown in Fig. 7 of the time constant of preemphasis circuit and the increase of level vertically degree.At vertical blanking period, the weighting of subcarrier chrominance signal realizes by coefficient circuit 31 and 33, and at this moment, the time constant of preemphasis circuit and level increase degree are approximately shown in Figure 7 half.Therefore, the subcarrier chrominance signal that discharges from 28 ends of Fig. 1 has the waveform shown in Figure 15 (c).Simultaneously, in the subcarrier chrominance signal shown in Figure 15 (c), before the transfer point and phase place afterwards be discontinuous, but the signal of previous field does not partly exert an influence to the beginning in the vertical-scan period of next.
A specific embodiments of deaccentuator is described below in conjunction with Fig. 2.In Fig. 2, revert to the logical playback subcarrier chrominance signal of grandfather tape with one and be added to 40 ends, then the subcarrier chrominance signal of resetting is added on subtraction circuit 41 and the add circuit 42.The output signal of subtraction circuit 41 is added on the switching circuit 44 through 1 row delay circuit 43, and shifts out from the 44b end or the 44c end of switching circuit 44.Allow the signal that shifts out from 44b and 44c separately by coefficient circuit 45 and 46 respectively, also adds in the subtraction circuit 41 through phase-adjusting circuit 47 feedbacks.The output signal of subtraction circuit 41 is added to the 50b end and the 50c end of switching circuit 50 through coefficient circuit 48 and 49, and the 50b of switching circuit 50 is held or the signal of arbitrary end of 50c end shifts out from 50a and is added on the add circuit 42 by phase regulator 51.Coefficient L with coefficient circuit 45 and 46
1And L
3Be set at, for example, 0.87 and 0.74, and with the coefficient L of coefficient circuit 48 and 49
2, L
4Be set at 0.13 and 0.26.
The switching pulse that enters into 52 ends is added on the pulse generator 53, on pulse generator 53, produces and be similar to the vertical blanking pulse shown in Figure 15 (E), and they are added on switching circuit 44 and 50.Between the low period of pulse, switching circuit 40 and 50 is connected to 44a and 44b end and 50a and 55b end, between high period, then is connected to 44a and 44c end and 50a and 55c end.
Therefore, in vertical scanning period, be weighting on coefficient circuit 45 and 48 with the playback subcarrier chrominance signal.At vertical blanking period, weighting realizes on coefficient circuit 46,49.At this moment, the level increase degree of its time constant and vertical direction is approximately half of coefficient of utilization circuit 45 and at 48 o'clock.
Add circuit 42 discharges a signal at 54 ends, and this signal is by obtaining from the playback subcarrier chrominance signal of input 40 with from the signal plus of phase regulator 51.This output signal is one to be possessed and the playback of the characteristic of postemphasising subcarrier chrominance signal is arranged (being called the playback subcarrier chrominance signal of postemphasising).In this postemphasises characteristic, the radio-frequency component of the input vertical direction spatial frequency of playback subcarrier chrominance signal on a frame, compare with low-frequency phase, on level, relatively decay, furtherly, this characteristic of postemphasising be when coefficient of utilization circuit 24 in Fig. 1 circuit with 26 the time with when coefficient of utilization circuit 45 just complementary mutually characteristic with 48 time with the characteristic of preemphasis circuit; And be when use constant circuit 31 with 33 with when coefficient of utilization circuit 46 with 49 the time just with the pre-emphasis characteristic characteristic of complementation mutually.
So, will have with the subcarrier chrominance signal of the complementary mutually characteristic of postemphasising of pre-emphasis characteristic at vertical scanning period and vertical blanking period and to take out from 54 ends.
Second kind of specific embodiments according to equipment of the present invention will be described below.Fig. 3 is the preemphasis circuit block diagram in the recording system of second kind of specific embodiments of present device.Fig. 4 is the deaccentuator block diagram in the playback system of second kind of specific embodiments of equipment of the present invention.The part that is analogous to Fig. 1 and Fig. 2 in Fig. 3 and Fig. 4 is marked with identical reference numbers, and its explanation is omitted.In Fig. 3, coefficient circuit 55 and 56 is respectively corresponding to coefficient circuit 24 and 31.For example, with the M of system
1Be similar to and be set at 0.76, and with M
3Be set at 0.31.Similarly, coefficient circuit 57 and 58 is respectively corresponding to coefficient circuit 26 and 33.For example with coefficient M
2Set, be approximately 0.24, and with M
4Be set at 0.69.
The subcarrier chrominance signal of taking out from subtraction circuit 22 is added on nonlinear circuit 59 and 60, nonlinear circuit 59 and 60 is amplitude limiters, in amplitude limiter, for example, the amplitude of input signal is limited to certain given numerical value, and amplitude is not limited less than the input signal of above-mentioned set-point and be to add not to be sent with revising.Little by the set-point of nonlinear circuit 59 amplitude limits ratio on level by the set-point of nonlinear circuit 60 amplitude limits.The subcarrier chrominance signal of taking out from nonlinear circuit 59 and 60 be multiply by coefficient M by coefficient circuit 61 and 62 respectively respectively
5(for example 1.3) and M
6(for example, 1.6) is added to switching circuit 63 and 63b end and 63c end to them respectively afterwards again.Switching circuit 63 is connected to 63a end and 63b end between the low period of the vertical blanking pulse that pulse generating circuit 35 is provided; Between high period, then be connected to 63a end and 63c end.Thereby the 63a by switching circuit 63 holds the subcarrier chrominance signal of taking out to be added on the add circuit 64, and here, it adds the subcarrier chrominance signal of an input 20, then from output 65 outputs.
Therefore, to passing through coefficient circuit 55 by the subcarrier chrominance signal of output 65 outputs, 57 and 61 and nonlinear circuit 59 provide a non-linear emphasis characteristic on the amplitude, its time constant and non-linear emphasis characteristic increase degree at the level of vertical direction and then are taken as the numerical value that is enough to reduce noise.At vertical blanking period, the non-linear emphasis characteristic by coefficient circuit 56,58 and 62 and nonlinear circuit 60 provide.Its time constant and non-linear emphasis characteristic when vertical direction and level increase degree and then approximately are aforementioned vertical cycle half.Therefore, the signal of previous field can not exert an influence to the signal of a back vertical scanning period.
Second specific embodiments of deaccentuator shown in Figure 4 is described below again. Coefficient circuit 66,67,68 and 69 corresponds respectively to the coefficient circuit 45,46,48 and 49 among Fig. 2, therefore, and coefficient N
1, N
2, N
3And N
4Elect as respectively, for example, 0.7,0.55,0.13 and 0.45.The playback subcarrier chrominance signal that to take out from subtraction circuit 77 is added on the coefficient circuit 72,73 through after having nonlinear circuit 70,71 with spline structure with nonlinear circuit 59,60, and here, the playback subcarrier chrominance signal is multiplied by N
5(for example, 0.57), N
6(for example, 0.60), be added to the 74b on the switching circuit 74 afterwards again, the 74c end, switching circuit 74,74a and 74b end are provided between the low period of the vertical blanking pulse that is provided by pulse generating circuit 53, between high period, then connect 74a and 74c end, thereby the subcarrier chrominance signal that the 74a end is taken out is added on the subtraction circuit 75.Subtraction circuit 75 carries out subtraction.In this computing, playback subcarrier chrominance signal from input 40 deducts in vertical scanning period by coefficient circuit 66,68,72 and the subcarrier chrominance signal of nonlinear circuit 70 and in the subcarrier chrominance signal of vertical blanking period by coefficient circuit 67,69,73 and nonlinear circuit 72, have and the non-linear emphasis characteristic of circuit shown in Figure 3 in vertical scanning period and the vertical blanking period playback subcarrier chrominance signal of the complementary characteristic of postemphasising mutually thereby produce one.Then, above-mentioned playback subcarrier chrominance signal is again from output 76 outputs.
Fig. 5 is a kind of specific embodiments block diagram that preemphasis circuit and deaccentuator constitute an omnibus circuit.The following describes its replay operations.In video reproduction, change its switching circuit 81,83,103 and 104, and be connected to contact P.At this moment, through switching circuit 81, subtraction circuit 84 and 1 row delay circuit 85 are added to the 86a end of switching circuit 86 with the playback subcarrier chrominance signal of coming input 80, and 86b and the 86c end from switching circuit 86 takes out then.Pass through coefficient circuit 87 and 88 respectively from the signal of 86b end and the taking-up of 86c end, and further pass through phase regulator 89, feed back again and add in the subtraction circuit 84.An output signal of subtraction circuit 84 is added on the 92b and 92c of switching circuit 92 through coefficient circuit 90 and 91, and the signal of arbitrary end of the 92b of the switching circuit 92 that takes out from 92a end and 92c is added on the subtraction circuit 94 through phase regulator 93, deducts from the playback carrier chrominance signal from switching circuit 81 then again.The output signal of subtraction circuit 94 is added to the 99b and the 99c end of switching circuit 99 through nonlinear circuit 95,96 and coefficient circuit 97,98, and the signal that will take out from the 99a end of switching circuit 99 is added on the subtraction circuit 100 again.
On the other hand, pulse generating circuit 102 produces and roughly the same vertical blanking pulse mutually shown in Figure 15 (E) from the switching pulse from input 101, and will be added on switching circuit 86,92 and 99 than vertical blanking pulse.Therefore, in vertical scanning period, connect 86a and 86b, 92a and 92b and the 99a and the 99b of switching circuit 86,92 and 99, and, connect 86a and 86c, 92a and 92c and 99a and 99c at vertical blanking period.In this way, the playback carrier chrominance signal from switching circuit 81 deducts in vertical scanning period through the signal of nonlinear circuit 95 and coefficient circuit 97 and at the signal of vertical blanking period through nonlinear circuit 96 and coefficient circuit 98.Like this, have different non-linear deemphasis characteristics at vertical scanning period and vertical blanking period, thereby the playback subcarrier chrominance signal that is similar to the output signal of subtraction circuit 75 shown in Figure 4 takes out from subtraction circuit 100, and through switching circuit 104, again from output 105 outputs.
On the other hand, in recording process, switching circuit 81,83,103 and 104 all are connected on the contact R, therefore, and from the subcarrier chrominance signal process switching circuit 81 of input 80, differential amplifier 82, switching circuit 83, subtraction circuit 84,1 row delay circuits 85, switching circuit 86, coefficient circuit 87 or 88 and phase regulator 89 be added on the subtraction circuit 84.The subcarrier chrominance signal of taking out from subtraction circuit 84 is added on 1 row delay circuit 85 and coefficient circuit 90 and 91.Signal through coefficient circuit 90 or 91 is come out to be added on the subtraction circuit 94 through phase regulator 93 from switching circuit 92, on subtraction circuit 94, subcarrier chrominance signal from switching circuit 81 deducts above-mentioned signal, and then is added on nonlinear circuit 95 and 96.
According to this specific embodiments,, make it to go to reduce to revert to deaccentuator the ratio (for example, the gain that makes differential amplifier 77 is G, and then it only comprises the deviation of 1/G) of original waveform because nonlinear circuit 95 and 96 are provided.
In above-mentioned specific embodiments, when the deaccentuator of structure is put the feedback loop of differential amplifier 82 into as shown in Figure 4, can draw pre-emphasis characteristic.Here must be noted that, also can put the preemphasis circuit of structure as shown in Figure 3 in the feedback loop of differential amplifier 82 into, in order to obtain to postemphasis characteristic.
The present invention is not limited to above-mentioned some specific embodiments, and in the above-described embodiment, for example, the output that phase regulator is arranged on coefficient circuit must be noted that on one side here, and also the input that can be arranged on coefficient circuit to phase regulator on one side.
In above-mentioned some specific embodiments,, must be noted that they also can be used for the subcarrier chrominance signal of pal mode although the description of being done is the subcarrier chrominance signal of TSC-system formula to be subjected to preemphasis and to postemphasis.Yet, in this case, in the subcarrier chrominance signal of pal mode, that each row of color sub-carrier of one of two kinds of color difference signals is once anti-phase.Therefore, delay circuit 23,43 and 85 is designed to have the time of delay of 2 natural multiples of going.And, nonlinear circuit 59,60,70,71,95 and 96 also to be not limited to be the amplitude amplitude limiter.
Fig. 6 is the block diagram that equipment according to the present invention is arranged on the 4th kind of specific embodiments of the preemphasis circuit in the recording system.Fig. 8 is the block diagram that equipment according to the present invention is arranged on the 4th kind of specific embodiments of the deaccentuator in the playback system.Except recording of proposing of preemphasis circuit 5 and deaccentuator 16 and the applicant different with the preemphasis circuit in the playback system equipment with deaccentuator and, equipment of the present invention all is similar with the structure shown in Figure 13 structurally.In Fig. 6, be marked with same reference numbers with part similar among Figure 14, its explanation is omitted.In Fig. 6, from the subcarrier chrominance signal of input 20 be added to subtraction circuit 21 and 22 and coefficient circuit 31 on.It is to receive in order to work as that coefficient circuit 31 is set, for example, during subcarrier chrominance signal shown in Fig. 7 (A), this signal adjusted to the part subcarrier chrominance signal (this is to comprise the portion waveshape that does not have the distortion due to the transmission response) of exporting this class distortion such as overshoot and ring that do not comprise that has shown in Fig. 7 (C) of taking from subtraction circuit 22 have same amplitude, discharge then.Like this, since not have in the subcarrier chrominance signal of subtraction circuit 22 output since due to the transmission response amplitude of the waveform portion of distortion and coefficient circuit 31 export the amplitude of subcarrier chrominance signals at one time almost on same level.
The preemphasis subcarrier chrominance signal of taking out from subtraction circuit 22 be added to switching circuit 32 ' 32a ' end, from coefficient circuit 31 taking-ups only level be adjusted but the subcarrier chrominance signal that do not have a pre-emphasis characteristic be added to switching circuit 32 ' 32b ' end on.On the other hand, the horizontal-drive signal of separating from the luminance signal that is write down is added on the burst gate pulse generation circuit 29 through input 34, here, with the way of knowing, produce a burst gate pulse shown in Fig. 7 (B), this pulse all is a high level on two periods continuously; (a period of time is from T between the transmission period of the burst signal in the input subcarrier chrominance signal shown in Fig. 7 (A) of input 20
1, another section period is T between above-mentioned transmission period
1End point after given period T
2).And except last mentioned during during in, be low level.With this burst gate pulse as switching circuit 32 ' switching pulse.(T between high period
1+ T
2) the input subcarrier chrominance signal of its 32b ' end of gating, and the input subcarrier chrominance signal shown in gating Fig. 7 (C) between low period.
Therefore, output 28 from switching circuit 32 ' common port provides such pre-emphasis characteristic, wherein during the input of the burst signal of input in the subcarrier chrominance signal and during, relatively amplify on level with regard to the radio-frequency component of the relevant vertical spatial frequency of its subcarrier chrominance signal (colour signal of modulation).Shown in Fig. 7 (D), the subcarrier chrominance signal of taking-up comprises a burst signal (being shown in the CB among Fig. 7 (A)) that does not have pre-emphasis characteristic for its burst signal.CB among Fig. 7 (D) shown with Fig. 7 (A) shown in the input subcarrier chrominance signal in the corresponding burst signal of burst signal.Owing to be shown in burst gate pulse among Fig. 7 (B) the given period T after between the burst signal transmission period, finishing
2Be in high level, then from Fig. 7 (C) and (D) as can be seen, the distortion components that subtraction circuit 22 outputs occur also can be eliminated after both having made end point between the burst signal transmission period.
According to this specific embodiments, in burst signal because not because of there being the distortion components due to the preemphasis, thereby might solve subcarrier chrominance signal that the application proposes record with reproducing device in the problem that run into.
Below, the 4th specific embodiments of deaccentuator is described in conjunction with Fig. 8.In Fig. 8, end points 40 receives the playback subcarrier chrominance signal that reverts to original frequency band, and above-mentioned playback subcarrier chrominance signal is added to subtraction circuit 41, add circuit 42 and coefficient circuit 49 ' on.An output signal of subtraction circuit 41 is through 1 row delay circuit 43, and coefficient circuit 45 and phase regulator 47 feed back adds subtraction circuit 41, and through coefficient circuit 48 ' and phase regulator 51 and to add circuit 42.Phase regulator 47 is similar to phase regulator 25, is to be used for adjusting phase place to make it to obtain the circuit that accurate 1 row postpones output.The coefficient L of coefficient circuit 45
1Elect as, for example, 0.87, and the coefficient L of coefficient circuit 48
2' elect as, for example, 0.18.
Add circuit 42 from the playback subcarrier chrominance signal of 40 ends with carry out addition from the playback subcarrier chrominance signal of phase regulator 51, resulting signal, add to switching circuit 44 ' 44a ' end.This output signal is a playback subcarrier chrominance signal that has such characteristic of postemphasising, (the playback subcarrier chrominance signal of promptly postemphasising), in this postemphasises characteristic, input playback subcarrier signal is at the radio-frequency component of the spatial frequency of the vertical direction of frame, compare with low-frequency component, on level, relatively decay.The characteristic of postemphasising just in time is the characteristic of pre-emphasis characteristic complementation, and its whole level augmenting portion to aforementioned pre-emphasis characteristic on level is decayed.
On the other hand, be provided with coefficient circuit 49 ' purpose with that the purpose of coefficient circuit 31 is set is similar, and the subcarrier chrominance signal of its output is added to the 44b ' end of switching circuit 44.
Therefore, the subcarrier chrominance signal of coming out from add circuit 42 is to during beyond during the burst signal input of input playback subcarrier chrominance signal, provides the characteristic of postemphasising.This subcarrier chrominance signal from switching circuit 44 ' open end take out, enter into output 54; And between this burst signal transmission period, then from the do not take burst signal of the playback that increases the weight of characteristic of coefficient circuit 49 ' taking-up.
Below, illustrate according to the 5th kind of specific embodiments described in the equipment claim 4 of the present invention.Fig. 9 is according to equipment of the present invention, and in the recording system of its 5th kind of specific embodiments, the block diagram of preemphasis circuit, Figure 11 are in the playback system according to equipment of the present invention, the block diagram of deaccentuator.The part that is similar to Fig. 6 and Fig. 8 among Fig. 9 and Figure 11 is marked with same reference number, and its explanation is omitted.In Fig. 9, coefficient circuit 55 is corresponding to coefficient circuit 24, and with coefficient M
1Be taken as, for example, be approximately 0.76.Similarly, coefficient circuit 57 is corresponding to coefficient circuit 26, and with coefficient M
2Be taken as, for example, be approximately 0.24.
The subcarrier chrominance signal of taking out from subtraction circuit 22 is added on the nonlinear circuit 59, nonlinear circuit 59 is amplitude limiters, and it is limited in the amplitude of input signal, for example, a certain given numerical value, its amplitude does not discharge less than the input signal of above-mentioned given numerical value with then not being subjected to amplitude limit.The subcarrier chrominance signal of taking out from nonlinear circuit 59 multiply by a coefficient M coefficient circuit 61
5(for example, being approximately 1.3); This signal is through switching circuit 63 ' be added on the add circuit 64 afterwards; Here this signal adds and is discharged into output 65 then from the subcarrier chrominance signal of input 20.The output signal of output 65 has as one does according to the amplitude of subcarrier chrominance signal that the subcarrier chrominance signal of non-linear emphasis characteristic discharges.
If the subcarrier chrominance signal shown in Figure 10 (A) enters input 20, then signal shown in Figure 10 (B) just appears at the output of subtraction circuit 21, and signal shown in Figure 10 (C) just appears at the output of subtraction circuit 22.It is the poor of two signals shown in Figure 10 (A) and Figure 10 (B).Then, when the frequency characteristic of 1 row delay circuit 23 is incorrect, remain with the distortion of transmission response in the then above-mentioned signal.Switching circuit 63 ' be subjected to is from the switch control of the burst gate pulse on burst gate pulse generator road 29, so that switching circuit 63 ' only between the burst signal transmission period and subsequently and then a given period turn-off, and outside during above-mentioned during connect.Therefore, the signal shown in Figure 10 (D) is from switching circuit 63 ' take out and be added on the add circuit 64.Therefore, during except that between the burst signal transmission period, from add circuit 64 taking-ups are the subcarrier chrominance signals that have the non-linear emphasis characteristic, and between the colour burst transmission period, taken out be from input 20 Calais do not add any correction, do not have the burst signal in the subcarrier chrominance signal of pre-emphasis characteristic.
Below, the 5th kind of specific embodiments of deaccentuator shown in Figure 11 is described, coefficient circuit 66 and 67 respectively corresponding to the coefficient circuit among Fig. 8 45 and 48 ', therefore, coefficient N
1And N
3Be taken as respectively, for example, 0.87 and 0.13.From the playback subcarrier chrominance signal of subtraction circuit 41 ' taking-up, warp and the nonlinear circuit 70 that nonlinear circuit 59 has same structure are added on the coefficient circuit 72, and here, signal is multiplied by coefficient N
5(for example, 0.57) is afterwards through switching circuit 74 ' be added on the subtraction circuit 75.Switching circuit 74 ' only resetting between colored burst signal transmission period and and then turn-offing in one section given period subsequently, therefore, because the effect of the gate pulse of burst gating pulse generation circuit 29 does not have subcarrier chrominance signal to occur at this; Thereby stoped the output signal of coefficient circuit 72 to deliver to subtraction circuit 75; And outside during above-mentioned, this switch connection, thus the output signal of coefficient circuit 72 is added on the subtraction circuit 75, and subtraction circuit 75 is finished subtraction; By this subtraction, in during except between the burst signal transmission period and back to back subsequently one section given period other, deduct the playback subcarrier chrominance signal of switching circuit 74 ' output from input 40 playback subcarrier chrominance signals, thereby produce a playback subcarrier chrominance signal that has with the non-linear deemphasis characteristic of pre-emphasis characteristic complementation, and it is discharged into input 76.Between the transmission period of burst signal, subtraction circuit 75 is delivered on the output 76 from the burst signal in the playback subcarrier chrominance signal that does not add any correction of input 40 one.
Figure 12 is a specific embodiments block diagram that constitutes a kind of circuitry of preemphasis circuit and deaccentuator with general circuit.Replay operations at first is described.At playback time, switch 81,83,103 and 0 104 all change and are connected to the P contact.Therefore, come input 80 and playback subcarrier chrominance signal, subtraction circuit 84,1 row delay circuits 85, coefficient circuit 87 and phase regulator 89 and be added on the subtraction circuit 84 through switch 81; Here, the playback subcarrier chrominance signal from switch 81 back delegation deducts said signal.An output signal of subtraction circuit 84 is added to 1 row delay circuit 85 and process coefficient circuit 90 and phase regulator 93 to be added on the subtraction circuit 85.In subtraction circuit 85, deduct above-mentioned output signal from the playback subcarrier chrominance signal of switch 81, afterwards this signal through nonlinear circuit 95 and coefficient circuit 97 be added to switching circuit 99 ' on.
On the other hand, will be added on the burst gate pulse generation circuit 29 from the playback line synchronizing signal of input 101; Here, this playback line synchronizing signal is converted to after the burst gate pulse with this gate pulse as switching circuit 99 ' switching pulse.At this, switching circuit 99 ' the control of switch and switching circuit 74 ' similar.Signal between the transmission period therefore, just except between the burst signal transmission period is through switching circuit 99 ' be added on the subtraction circuit 100; On this subtraction circuit 100, from the playback subcarrier chrominance signal of switch 81 deduct above-mentioned from switching circuit 99 ' signal.Therefore, except between the burst signal transmission period during in, the playback subcarrier chrominance signal that has the non-linear deemphasis characteristic of taking out from subtraction circuit 100 is similar with the output signal of the subtraction circuit 75 that is shown in Figure 11; This signal is discharged on the output 105 through switch 104.In this specific embodiments, because nonlinear circuit 95 is provided, make the ratio (for example, make that G is the gain of differential amplifier 82, the deviation of 1/G then only occurs) that might reduce to return to original waveform by deaccentuator.
On the other hand, when recording, switch 81,83,103 and 104 all receive the P contact.Therefore, the subcarrier chrominance signal that enters input 80 is through switch 81, differential amplifier 82, and switch 83, subtraction circuit 84,1 row delay circuits 85, coefficient circuit 87 and phase regulator 89 are added on the subtraction circuit 84.The subcarrier chrominance signal of taking out from subtraction circuit 84 is added to 1 row delay circuit 85 and is added on the subtraction circuit 85 through coefficient circuit 90 and phase regulator 93, here, deduct this from phase-adjusted 93 signal from the subcarrier chrominance signal of switch 83, and then be added on the nonlinear circuit 95.
In above-mentioned specific embodiments, deaccentuator is as shown in figure 11 put into the feedback control loop of differential amplifier 82, thereby when obtaining pre-emphasis characteristic, should be noted that, also can place preemphasis circuit as shown in Figure 9 the feedback control loop of differential amplifier 82, thereby obtain the characteristic of postemphasising.
The present invention is not limited to above-mentioned specific embodiments, and in addition, for example, although in the specific embodiments of all fronts, phase regulator all is arranged on output one side of coefficient circuit, also can be arranged on it input one side of coefficient circuit.
And, the explanation of being done in above-mentioned specific embodiments all is that the subcarrier chrominance signal of TSC-system formula is subjected to preemphasis and postemphasises, also should be noted that simultaneously, these also are the subcarrier chrominance signals that can be used for pal mode, yet, in this case, in the subcarrier chrominance signal of pal mode, the color sub-carrier signal of a kind of color difference signal in all color difference signals, each provisional capital position that will have anti-time phase; Therefore, aforesaid delay circuit 23,43 and 85 will be designed to make it to have the time of delay of the natural multiple that postpones 2 row.In addition, to be not limited to be amplitude limiter to nonlinear circuit 59,70 and 95.
As previously mentioned, according to equipment of the present invention, include a coefficient of recording that has preemphasis circuit; In this preemphasis circuit, about a certain scheduled period; At least comprise a vertical blanking period time constant or during the level of constant and vertical direction increase degree the two all be made into less than time constant with regard to during outside its above-mentioned scheduled period with regard to and the increase of the level on vertical direction degree; Simultaneously, the above-mentioned subcarrier chrominance signal that provide is compared at the radio-frequency component and the low-frequency component of vertical spatial frequency, discharges after relatively increasing on the level again; Also include a playback system that has deaccentuator, this deaccentuator, during above-mentioned scheduled period and other in, above-mentioned relatively preemphasis circuit each relevant during in characteristic the characteristic of a complementation is arranged; The vertical high frequency composition of the subcarrier chrominance signal that this wherein resets and low-frequency phase are relatively relatively discharging after the decay on the level again.Therefore, same with the previously presented equipment class of the applicant, the present invention can make the letter of playback subcarrier chrominance signal/make an uproar than being improved, simultaneously, it is not because the vertical spatial frequency characteristic (vertical resolution) due to the deaccentuator can be owing to have used the effect that makes deterioration of image quality that correlation ran into of row as traditional noise reducing circuit yet.Also have, the signal of previous field can partly not exert an influence to the beginning of vertical scanning period in next.Thereby prevented that the first half generation tone of resetting at frame from disturbing and amplitude is disturbed, also prevented because the variation of the line period that distortion distortion caused.Have again, only be provided with a non-linear emphasis circuit or a non-linear deemphasis circuit record with reproducing device in, the amplitude of subcarrier chrominance signal can be so not nervous to recording and resetting, the subcarrier chrominance signal of the original signal waveform of therefore resetting out in this tape that just might record with existing video tape recorder (VTR), do like this, both made above-mentioned signal allow also not have any practical difficulty by the non-linear deemphasis circuit.On the other hand, also can use existing video tape recorder, the original auxiliary of from the tape of recording according to equipment of the present invention, resetting out carrier-chrominance signal waveform, and do not have any practical difficulty.Thus, equipment of the present invention and existing video tape recorder have interchangeability.
In addition, according to the present invention, only to the subcarrier chrominance signal vertical spatial frequency preemphasis during beyond between the burst signal transmission period with postemphasis.Therefore, the equipment class that proposed in the past with the applicant with, the present invention has such effect, can be so that the letter of the chrominance signal of resetting/make an uproar than being improved.And, can be by the vertical space characteristic (vertical resolution) due to postemphasising owing to do not use the correlation of branch to suffer deterioration as traditional noise reducing circuit.Moreover, both made delay line that such characteristic is arranged, owing to exist this frequency characteristic to make it have the ability of undistorted ground transmitting subcarrier carrier chrominance signal, for synchronizing signal, do not influence above-mentioned preemphasis and postemphasis.Therefore, burst signal with distortion occurs owing to the deterioration of transmission characteristic and have nothing to do, thereby with burst signal with distortion occurs owing to the deterioration of transmission characteristic and have nothing to do, thereby with the amplitude of burst signal and phase place as benchmark among the work of a subcarrier chrominance signal process circuit (such as automatic phase control (APC) circuit and autochroma control (ACC) circuit), can't bring inconvenience; Thereby this just might prevent the decline of reproduction quality.Have again, between several departures date of beginning on the scene, the amplitude of burst signal with other during the time the same, therefore, the complementary characteristic fully not influence of the work of autochroma control (ACC) circuit to increasing the weight of, and therefore improved the complementary characteristic that increases the weight of.In addition, only be equipped with a non-linear emphasis circuit or a non-linear deemphasis circuit record with reproducing device in.The amplitude of subcarrier chrominance signal is not so nervous recording and resetting, therefore, the subcarrier chrominance signal of this original signal waveform of just might from the tape that existing video tape recorder is recorded, resetting out, this playback, both made and allowed above-mentioned signal by the non-linear deemphasis circuit, do not have practical difficulty yet, on the other hand, the subcarrier chrominance signal waveform that might adopt existing video tape recorder (VTR) from the tape of recording according to equipment of the present invention, to reset out original.And practical difficulty not.Thus, equipment of the present invention and existing tape recorder (VTR) have interchangeability.
Fig. 1 and Fig. 2 illustrate the block diagram of equipment according to the present invention by the essential part of recording coefficient and playback system of first kind of specific embodiments; Fig. 3 and Fig. 4 illustrate equipment according to the present invention by the recording system of second kind of specific embodiments and the block diagram of the playback system basic element of character; Fig. 5 illustrates the block diagram of equipment according to the present invention by the basic element of character of the third specific embodiments; Fig. 6 and Fig. 8 illustrate the block diagram of equipment according to the present invention by the basic element of character of the recording system of the 4th kind of specific embodiments and playback system; Fig. 7 illustrates the signal waveforms in order to the work that block diagram shown in Figure 6 is described; Fig. 9 and Figure 11 illustrate the block diagram of equipment according to the present invention by the basic element of character of the recording system of its 5th kind of specific embodiments and playback system; Figure 10 illustrates the signal waveforms in order to the work that block diagram shown in Figure 9 is described; Figure 12 illustrates the block diagram of equipment according to the present invention by the basic element of character of its 6th kind of specific embodiments; Figure 13 illustrates the subcarrier chrominance signal that was proposed in the past by the applicant to record block diagram with an embodiment of reproducing device; Figure 14 is the block diagram of an embodiment that the recording system basic element of character of the equipment that was proposed in the past by the applicant is shown; Figure 15 illustrates the working signal oscillogram in order to key diagram 1 and block diagram shown in Figure 14; Figure 16 is the signal waveforms in order to the work that block diagram shown in Figure 14 is described; Figure 17 illustrates the signal waveforms in order to the work of explanation Figure 13 and block diagram shown in Figure 14.
1 ... the color picture signal input, 2 ... in order to the low pass filter of brightness signal separation, 3 ... band pass filter in order to the separated sub carrier chrominance signal, 5 ... preemphasis circuit, 6 ... record the subcarrier chrominance signal treatment circuit, 9 ... magnetic circuit, 16 ... deaccentuator; 18 ... the color picture signal output of resetting, 20 ... the subcarrier chrominance signal input, 21,22,41,41 ', 75,77,84,85,94 and 100 ... subtraction circuit, 29
Burst gate pulse generation circuit.
Claims (4)
1, a subcarrier chrominance signal is recorded and reproducing device, be used for to convert to from the subcarrier chrominance signal that color picture signal is separated a certain prearranged signals form so that it is recorded in a certain recording medium, and at playback time, from the above-mentioned playback subcarrier chrominance signal that obtains a primary signal form in the replay signal of resetting the medium of recording, this equipment includes a recording system that preemphasis circuit is housed, in this preemphasis circuit, the radio-frequency component of its vertical spatial frequency of subcarrier chrominance signal that will provide, compare with low-frequency component, after relatively increasing on the level, discharge again; This equipment also comprises a playback system that deaccentuator is housed, this deaccentuator, characteristic to said preemphasis circuit has a characteristic complementation, and the vertical high frequency composition of the subcarrier chrominance signal of resetting, compare with low-frequency component, relatively discharge again after the decay, it is characterized in that with respect to a certain scheduled period, at least the preemphasis level that comprises the time constant of a vertical blanking period or its time constant and vertical direction increases degree, and the two all is made into time constant and vertical direction level increase degree less than speech during beyond its scheduled period, and with respect to the said scheduled period, the level that postemphasises of time constant or its time constant and vertical direction reduces degree, and the two all is made into less than time constant and vertical direction level with regard to during beyond its scheduled period and reduces degree.
2, according to claim 1 records and reproducing device, it is characterized in that in preemphasis circuit, amplitude according to above-mentioned subcarrier chrominance signal, the high pre-composition of the vertical spatial frequency of the feasible subcarrier chrominance signal that will provide, on level, increase, and in deaccentuator, according to the amplitude of above-mentioned subcarrier chrominance signal, make the radio-frequency component of the pre-rate of vertical space of the playback subcarrier chrominance signal return to above-mentioned primary signal form, on level, decay.
3, a subcarrier chrominance signal is recorded and reproducing device, be used for to convert to from the subcarrier chrominance signal that color picture signal is separated a certain prearranged signals form so that it is recorded in a certain recording medium, and at playback time, from the above-mentioned playback subcarrier chrominance signal that obtains a primary signal form in the replay signal of resetting the medium of recording, this equipment includes a recording system that preemphasis circuit is housed, in this preemphasis circuit, the radio-frequency component of its vertical air frequency of the subcarrier chrominance signal that will provide, compare with low-frequency component, after relatively increasing on the level, discharge again; This equipment also comprises a playback system that deaccentuator is housed, this deaccentuator, characteristic to said preemphasis circuit has a characteristic complementation, and the vertical high frequency composition of the subcarrier chrominance signal of resetting, compare with low-frequency component, relatively discharge again after the decay, it is characterized in that for the burst signal in the said subcarrier chrominance signal that applies, preemphasis is actually and stops, do not provide above-mentioned level and increase characteristic, and for the burst signal in the said playback subcarrier chrominance signal, postemphasising to be actually stops, and does not provide above-mentioned level attenuation characteristic.
4, according to claim 3 records and reproducing device, it is characterized in that amplitude according to above-mentioned subcarrier chrominance signal, during the burst signal input, the radio-frequency component of the vertical spatial frequency of the subcarrier chrominance signal that will provide is provided, on level, increase, amplitude according to above-mentioned subcarrier chrominance signal, during the burst signal input, make the radio-frequency component of the vertical spatial frequency of the playback subcarrier chrominance signal that returns to above-mentioned primary signal form, on level, decay.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN85107249.6A CN1003696B (en) | 1985-09-28 | 1985-09-28 | Carrier wave colour signal recording and reproducing device |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN85107249.6A CN1003696B (en) | 1985-09-28 | 1985-09-28 | Carrier wave colour signal recording and reproducing device |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN85107249A CN85107249A (en) | 1987-04-08 |
| CN1003696B true CN1003696B (en) | 1989-03-22 |
Family
ID=4795537
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN85107249.6A Expired CN1003696B (en) | 1985-09-28 | 1985-09-28 | Carrier wave colour signal recording and reproducing device |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN1003696B (en) |
-
1985
- 1985-09-28 CN CN85107249.6A patent/CN1003696B/en not_active Expired
Also Published As
| Publication number | Publication date |
|---|---|
| CN85107249A (en) | 1987-04-08 |
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