JPH07284075A - Video signal transmission system and high definition television receiver - Google Patents

Abstract

PURPOSE:To prevent picture quality from being substantially damaged by inhibiting a high definition reception processing from being performed to high definition video signals transmitted from a present broadcasting system recording and reproducing device to a high definition TV receiver at the time of reproduction in the high definition TV receiver. CONSTITUTION:An ID sampling circuit 52 performs a processing for sampling a 23-rd line where an ID signal is present. When it is discriminated that the state of a color plus bit is '1', a discrimination circuit 53 outputs rewrite control signals for rewriting the state of the color plus bit from '1' to '0' to an ID rewrite circuit 54. The ID rewrite circuit 54 rewrites the state of the color plus bit inside an ID area provided in the 23rd line of supplied composite signals from '1' to '0' corresponding to the rewrite control signals and outputs composite video signals to a VTR recording system 55. The VTR recording system 55 YC-separates the composite video signals supplied from the circuit 54, performs a required recording signal processing and then, performs recording in a tape head system.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a video signal transmission system and a high quality TV receiver.

[0002]

2. Description of the Related Art FIG. 7 is a block diagram of a Color plus system encoder, and FIG. 8 is a block diagram of a Color plus system decoder.
FIG. 9 is a block diagram of a Color plus compatible TV receiver capable of discriminating the reception mode, and FIG. 10 is a block diagram of a PAL system home VTR.

In Europe, the current terrestrial broadcasting PAL (Ph
EDT compatible with ase Alternation by Line) method
Various V (Extended Definition TV, high resolution TV) have been developed. One of them is the "Color plus" method proposed by Grundig, a German electric manufacturer. And this is EDT compatible with PAL system
This is a further improvement of the "Q-PAL" method which is another method of V.

That is, in the Color plus system, when transmitting the composite video signal obtained by removing the crosstalk between the luminance signal and the color signal, the PAL modulation signal of the PAL modulation signal is transmitted on the transmitting side before the PAL modulation of the color signal. The vertical-time filter (that is, a filter for three-dimensional pre-comming) that removes the luminance signal component mixed in the occupied band in advance removes the luminance signal component (crosstalk component) to a higher frequency band. It was improved as much as possible. That is,
A composite video signal obtained by adding the high frequency component of the luminance signal and the color signal between the fields is transmitted. The receiving side performs signal processing that is complementary to the previous signal processing performed on the transmitting side, so that the transmitted composite video signal is converted into a luminance signal and a color signal without crosstalk between the luminance signal and the color signal. Can be separated and taken out.

The encoder 1 on the transmission side of the above-mentioned Color plus system is constructed as follows. That is, as shown in FIG. 7, the encoder 1 includes a matrix circuit 2 to which R, G, B (red, green, blue) three primary color signals are supplied, and a luminance signal (Y signal) output from the matrix circuit 2. Low pass filter (LPF) 3, high pass filter (HP)
F) 4, a low-pass filter (LPF) 5 to which the color signal U output from the matrix circuit 2 is supplied, a low-pass filter (LPF) 6 to which the color signal V is supplied, and the above-mentioned low-pass filter 3
The output timing of the low frequency Y signal output from
^* A time compensation circuit 7 for time-compensating the low-pass Y signal so as to be synchronized with the output timing of the signal, and a field-added Y signal obtained by adding the high-pass Y signal output from the high-pass filter 4 for one field. (Y ^* signal) is output from the field addition circuit 8, the low-frequency Y signal output from the time compensation circuit 7 and the Y output from the field addition circuit 8.
^* Adder circuit 9 to which signals are respectively supplied, field adder circuits 10 and 11 that respectively output color signals obtained by adding the color signals U and V respectively output from the low-pass filters 5 and 6 for one field, It is composed of a modulation circuit 12 that performs PAL modulation for generating and outputting a carrier color signal (C signal) based on the field-added color signals output from the field addition circuits 10 and 11. The adding circuit 9 outputs the color plus composite video signal obtained by adding the low frequency Y signal, the Y ^* signal, and the C signal. Thus, the Color plus system encoder 1 can encode the input three primary color signals into a Color plus system composite video signal.

The decoder 21 on the receiving side of the above-mentioned Color plus system is constructed as follows. That is, the decoder 2
As shown in FIG. 8, the reference numeral 1 designates a low-pass filter (LPF) 22 and a high-pass filter (HP) to which the Color plus composite video signals generated by the encoder 1 are respectively supplied.
F) 23 and 24, so that the output timing of the low frequency Y signal obtained by separating from the composite video signal transmitted from the encoder 1 by the low frequency filter 22 is synchronized with the output timing of the high frequency Y signal described later. Further, a time compensating circuit 25 for time-compensating the low frequency Y signal, and a high frequency Y signal obtained by adding one field to the high frequency Y signal obtained by separating from the composite video signal by the high frequency filter 23 are output. After the PAL demodulation for generating and outputting the color signals U and V respectively based on the carrier color signal C obtained by separating from the composite video signal by the field addition circuit 26 and the high-pass filter 24 described above, these signals are unnecessary. The demodulation circuit 27 that removes the high frequency component, the addition circuit 28 that outputs the Y signal obtained by adding the low frequency Y signal and the high frequency Y signal output from the time compensation circuit 25 and the field addition circuit 26 described above, respectively. Conversely matrix circuit 29 having a complementary configuration as the matrix circuit 2 described above Y signal output from the adder circuit 28 is supplied, the above-mentioned demodulating circuit 2
The field adder circuits 30 and 31 for outputting the color signals U and V obtained by adding the signals output from 7 for one field, respectively.
Composed of. The above-mentioned inverse matrix circuit 29 uses the color signals U and V output from the field adding circuits 30 and 31,
Then, the primary color signals R, G, B are output based on the Y signal. Thus, the Color plus method decoder 21 inputs
It is possible to decode a Color plus composite video signal into three primary color signals.

The above-mentioned Color plus system uses the property that the video signal of the PAL system inverts the phase of the video signal every 312 lines (one field), and the luminance / carrier color signal separation (that is, YC) is performed for each field. Separation. FLD YC separation) is performed without error. That is, the transmitting (encoder) side performs precomming in the field direction, while the receiving (decoder) side adds 1 field (3
The Y signal is extracted by adding the 12-line delay signal) and the C signal is extracted by subtracting. The Color plus method uses encoders to perform such precomming, so the time resolution is inferior to the current PAL method, but YC
Cross-luminance, cross-color, etc., which are errors at the time of separation, cannot occur. That is, it is possible to obtain a high quality image.

Now, when the above-mentioned decoder 21 of the Color plus system is used by inserting it into the video signal transmission system, the composite video signal supplied to this decoder 21 is
Not only is the composite video signal of the system supplied, but the current PA
It may be considered that the L-type composite video signal is also supplied.
Therefore, the decoder 21 is operated only when the composite video signal of the Color plus system is supplied, while the PA
When the L-system composite video signal is supplied, the decoder 21 must be deactivated. Then, in order to automatically perform the operation and non-operation of the decoder 21, the Colo
In order to determine whether or not the r plus type composite video signal has been transmitted, it is necessary to provide an additional signal (ID signal) different from the video in the composite video signal. The method is discriminated by the presence or absence of this ID signal. If this determination cannot be made, even if a PAL system composite video signal is received by the Color plus system decoder, this signal will be decoded as described above using the Color plus system, resulting in decoding by the PAL system decoder. This causes a problem that a video signal with poor image quality is reproduced.

By the way, in the PAL plus system which is an EDTV system different from the above Color plus system,
To determine whether the video signal transmitted to the system decoder is of the PAL plus system, an additional signal (ID
Signal) is used. That is, the second of the transmitted video signal
Insert this ID signal into 3 lines and use the ID in the decoder.
By determining the presence / absence of a signal, it is possible to determine whether the PAL plus system is used. Specifically, among a large number of bits (about 20 bits) forming this ID signal, an undefined empty bit b ₆ is used, and in the case of this PAL plus system, bit b _{6 is set} to “1”, If not, the value is "0".

By using such a method for discriminating the ID signal system, it is possible to discriminate whether or not the video signal supplied to the decoder of the Color plus system is of the Color plus system by Color pl
An ID signal is provided in the 23rd line of the us system video signal, and an empty bit b ₅ is used as an example among a large number of bits (20 bits, b _{1 to} b ₂₀ ) that compose this ID signal having a maximum frequency of 833 kHz. When the signal of the Color plus system is used, bit b _{5 is set} to "1", and when the signal of the Color plus system is not set, it is set to "0".

By the way, as an example of using the above-mentioned Color plus system decoder 21, a specific configuration of a Color plus system compatible TV receiver capable of system discrimination using an ID signal (undefined bit b ₅ ). explain. Color pl
As shown in FIG. 9, the us system-compatible TV receiver 31
The inverse matrix circuit 29 in the configuration shown in FIG. 8 described above.
The YC separation circuit 32, which has substantially the same configuration as the one in which the color plus system is removed, performs the decoding process of the Color plus system composite video signal (including the three-dimensional comb filter), the YC separation process of the PAL system composite video signal, and the YC separation process. YC separation circuit 33 having a well-known color demodulation circuit configuration for outputting color signals U and V obtained by biaxially demodulating the reference subcarrier fsc (4.43 MHz) with the generated carrier color signal, the ID signal described above. The ID detection circuit 34 for detecting the 23rd line in which there is a line, the discrimination circuit 35 for discriminating the Color plus system based on the state of the bit b ₅ and outputting the switching control signal corresponding to this discrimination to the switch 36, the switch 36 (contact point). 36a, 36b, movable contacts 36c), a Y signal supplied via the switch 36, and color difference signals (RY, G) based on the color signals U, V.
-Y, BY) and a primary color output circuit (not shown) generates primary color signals (R, G, B) based on these color difference signals (RY, GY, BY). A signal processing circuit 37, a CR for receiving an image corresponding to the primary color signals (R, G, B)
It is composed of T38.

The TV receiver 31 having the above structure is
(1) When the PAL system composite video signal is received, the discrimination circuit 35 does not discriminate the Color plus system, and therefore the switching control signal output from this is at the “L” level, whereby the movable contact 36c of the switch 36 is It is switched to the contact 36b side. Further, (2) when receiving the composite video signal of the Color plus system, the switching control signal output from the discrimination circuit 35 becomes the "H" level, and the movable contact 36c of the switch 36 is switched to the contact 36a side. Thus, Co
The Color plus compatible TV receiver 31 capable of discriminating the lor plus system can receive both the current PAL system signal and the Color plus system signal in a good state.

Now, let us consider a case where the composite video signal of the above Color plus system is recorded and reproduced by the current PAL system home video tape recorder (hereinafter referred to as VTR).
That is, the VTR 41, as shown in FIG. 10, is a YC separation circuit 42 for separating the input composite video signal into YCs.
A known luminance signal recording system (Y that outputs an FM-modulated luminance signal obtained by FM-modulating the luminance signal output from the separation circuit 42)
System recording process) 43, a well-known color signal recording system (C system recording process) 44 for outputting a low-pass conversion color signal obtained by low-pass converting the carrier color signal output from the YC separation circuit 42, and these F
A multiplexing circuit 45 for frequency-multiplexing the M-modulated luminance signal and the low-frequency conversion color signal, a tape head system 46 including a video head and a magnetic tape for recording the frequency-multiplexed signal output from the multiplexing circuit 45, and this tape head system 46. A known luminance signal reproduction system (Y system reproduction processing) 47 which outputs a reproduction luminance signal obtained by FM demodulating a reproduced FM luminance signal based on a reproduction signal reproduced from the tape head system 46. A well-known color signal reproduction system (C system reproduction processing) 4 for outputting a reproduction carrier color signal obtained by inverse frequency converting the signal
8. A synthesis circuit 49 for outputting a reproduction composite video signal obtained by frequency-multiplexing these reproduction luminance signal and reproduction carrier color signal.

[0014]

By the way, the above-mentioned V
As is generally known, the YC separation circuit 42 that constitutes the TR 41 is composed of a low-pass filter that separates and outputs a luminance signal in a PAL composite video signal and a bandpass filter that separates and outputs a carrier color signal. , YC separation circuit 4
The composite video signal supplied to 2 is frequency-separated as described above regardless of the system and is supplied to the luminance signal recording system 43 and the chrominance signal recording system 44 in the next stage, respectively. However, when the above-described Color plus method composite video signal (composite video signal generated and output by the encoder 1 in FIG. 7) is supplied to the YC separation circuit 42, Co
Since the lor plus system composite video signal is forcibly separated and output into the luminance signal frequency component and the carrier color signal frequency component that make up the PAL system composite video signal, the bands of the luminance signal and the carrier color signal are both different. Signal.

When the well-known low-pass conversion color signal in the color signal reproducing system 48 constituting the above-mentioned VTR 41 is subjected to the inverse frequency conversion processing into the carrier color signal, a so-called APC color process is performed as a countermeasure against jitter. Here, the low-pass converted color signal is separated from the reproduced signal by a low-pass filter and restored to the original 4.43 MHz by inverse frequency conversion.
The color burst signal having the color subcarrier frequency of 4.43 MHz is compared with the phase of the reference color burst signal so as to return to a stable frequency, and the frequency of the frequency converting local oscillator is controlled by the voltage corresponding to the phase difference. . Thus, the phase of the reproduced carrier color signal is kept constant without jitter. It is well known that the phase stability of the reproduced carrier color signal is in a visually permissible range in a consumer TV receiver, but is inferior in stability to the broadcast signal.

Color pl reproduced from the VTR 41
The luminance signal that forms the us system composite video signal is skewed,
A time-axis fluctuation component such as jitter is included, so that stable YC separation cannot be performed by addition and subtraction with the above-mentioned 1-field delay signal. On the other hand, as described above, since the maximum frequency of the ID signal is 833 kHz, the V
Even TR can sufficiently transmit. Therefore, this ID signal
When the video signal of the Color plus system showing the Color plus system is recorded / reproduced by the home VTR 41 and is received by the TV receiver 31 shown in FIG. 9 described above, it is determined as Color plus from the detection of the ID signal. However, although the same process is performed (the movable contact 36c of the switch 36 is switched to the contact 36a side), the carrier color signal forming the video signal of the same system is converted into the broadcast signal as described above. In comparison (band)
Since the stability is inferior, the TV receiver 31 cannot perform accurate decoding processing, and appears as interference such as color unevenness on the screen.

[0017]

In order to solve the above problems, the present invention provides a video signal transmission system having the following configurations (1) to (3).

(1) A video signal transmission system for transmitting a series of high-definition video signals based on the current broadcasting system to a high-definition TV receiver, wherein the high-definition video signals are transmitted via the current broadcasting system recording / reproducing device. When the signal is an unsuitable signal to be transmitted to a high-definition TV receiver and has an identification signal indicating that it is a high-definition video signal, the high-definition video using the current broadcasting system recording / reproducing apparatus A rewriting means for rewriting the identification signal so as not to indicate that the signal is a high-definition video signal when recording or reproducing the signal,
An image characterized in that the high-definition video signal transmitted from the current broadcast recording / reproducing device to the high-definition TV receiver is not subjected to high-quality image reception processing by the high-definition TV receiver during reproduction. Signal transmission system.

(2) In the video signal transmission system according to the above (1), a removing means for removing a time axis fluctuation component from the high-quality video signal reproduced from the current broadcasting system recording / reproducing apparatus, and the removing means. Changing means for changing the identification signal of the high-definition video signal supplied from the means to a signal indicating that the high-definition video signal is a high-definition video signal, and the changing means changes the high-definition TV receiver. The high-definition video signal transmitted to the high-definition TV receiver is subjected to high-definition image reception processing.

(3) A high-definition TV receiver used in a video signal transmission system for transmitting a series of high-definition video signals based on the current broadcasting system to a high-definition TV receiver, which receives the high-definition video signal. Means, first switching means for switching and outputting a video signal supplied from an external device, and a high-quality video signal output from the receiving means, and the first switching means.
Is supplied from the first switching means, and an auxiliary signal demodulating means for detecting an identification signal indicating a high-quality video signal from the video signal output from the switching means, and performing high-quality image receiving processing based on the detection signal. And a second switching means for switching and outputting the video signal and a processed video signal obtained by performing high-quality image reception processing on the high-quality video signal based on the result of detecting the identification signal. The switching means of No. 2 is provided with an identification signal indicating that the video signal is an unsuitable signal to be transmitted to the high-definition TV receiver via the current broadcast recording / reproducing apparatus and is a high-definition video signal. High-definition TV receiver characterized by switching and outputting at least a video signal which is not subjected to high-quality image reception processing.

[0021]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A video signal transmission system according to the present invention will be described below with reference to FIGS. 1, FIG. 2, FIG. 5, and FIG. 6 are block diagrams of the first, second, third, and fourth embodiments of the video signal transmission system according to the present invention, and FIGS. 3 and 4 are video signal transmission systems, respectively. FIG. 11 is a waveform diagram for explaining the operation, and FIG. 11 is a fifth diagram of the video signal transmission system according to the present invention.
It is a block diagram of the high-definition TV receiver which is an Example. The same components as those described above are designated by the same reference numerals, and the description thereof will be omitted.

A video signal transmission system 51 according to the present invention,
As shown in FIG. 1, FIG. 2, and FIG. 5, which will be described later, the reference numerals 61 and 71 generate a series of high-quality video signals (Color plus system composite video signals) based on the current broadcasting system (PAL system).
A video signal transmission system for transmitting to a V receiver (TV receiver 31 compatible with Color plus system), wherein the high-definition video signal is a current broadcasting system recording / reproducing device (PAL system home V
A signal unsuitable to be transmitted to the high-definition TV receiver 31 via the TR41) (reproduced) (Colo in the TV receiver 31).
If the signal is a signal that cannot be received with high image quality as the r plus system composite video signal and is provided with an identification signal indicating that it is a high quality video signal (provided on the 23rd line of the Color plus system composite video signal) Co that identifies whether or not it is the Color plus method among the many bits that make up the specified ID area
If the lor plus bit b ₅ is “1 (Color plus system)”, it means that it is a high-definition video signal at the time of recording or reproducing the high-definition video signal using the current broadcasting system recording / reproducing device 41. (even if the bit b ₅ is "1", it is rewritten from "1" to "0 (Color plus non-system state)") for rewriting the identification signal so as not shown rewriting means (ID rewriting circuit 54,75, The high-definition video signal transmitted from the current broadcasting system recording / reproducing device 41 to the high-definition TV receiver 31 at the time of reproduction has a muting circuit 63). The video signal transmission system is characterized in that a signal which cannot be received as a high-quality composite video signal in the Color plus system is decoded by the TV receiver 31 in the Color plus system.

Further, the video signal transmission system 81 according to the present invention is, as shown in FIG. 6 described later, the high-quality video signal (Color) reproduced from the current broadcasting system recording / reproducing apparatus (PAL system home VTR 41). plus system video signal)
Removing means (time base collector (TBC) 82) for removing the time axis fluctuation (jitter) from the
Even if the identification signal of the high-definition video signal supplied from 2 is changed to a signal indicating that the high-definition video signal is a high-definition video signal (the above-mentioned bit b ₅ is “0”), Change means (ID rewriting circuit 75) for changing from "0" to "1"), and the high-definition video signal transmitted from the changing means 75 to the high-definition TV receiver 31 is the high-definition TV receiver 31. The video signal transmission system is characterized in that high-quality image reception processing is performed in the.

(First Embodiment) A video signal transmission system 51 according to the present invention uses a PAL for a composite video signal of the Color plus system.
Method When recording with a home VTR, Color plus bit b ₅
Is rewritten from "1" to "0" to obtain the Color plus composite video signal. That is, the video signal transmission system 51 according to the present invention, as shown in FIG.
When recording with the recording system of No. 1 (shown in FIG. 10), Color plus
Among the many bits forming the ID area (the "ID" portion shown in FIG. 3 (A)) provided in the 23rd line of the system composite video signal, the Color plus bit b ₅ for identifying whether or not the Color plus system is used. A configuration for performing signal processing (illustrated in FIG. 3B) for rewriting the state from “1” to “0” in advance (that is,
ID sampling circuit 52, discrimination circuit 53, ID rewriting circuit 54)
Is equipped with.

Here, the ID extracting circuit 52 uses the above-mentioned ID.
The processing is to extract the 23rd line in which a signal exists, and has the same configuration as the ID detection circuit 34 (shown in FIG. 9) described above. Discrimination circuit 53 is Color plus bit b
_When it is determined that the state of ₅ is "1", the ID rewriting circuit 54
Then, a rewrite control signal for rewriting the state of Color plus bit b ₅ from "1" to "0" is output. ID rewriting circuit 5
4 is the Color plus supplied in response to this rewrite control signal
The state of the Color plus bit b ₅ in the ID area provided on the 23rd line of the composite video signal of the method is "1" to "0"
Rewrite

Thus, the ID rewriting circuit 54 is Color plus.
The composite video signal of the Color plus system in which the state of bit b ₅ is “0” is output to the VTR recording system 55. The VTR recording system 55 includes the YC separation circuit 42 and the luminance signal recording system 4 described above.
3, a color signal recording system 44, a multiplexing circuit 45 (all shown in FIG.
0), the color plus type composite video signal supplied from the ID rewriting circuit 54 is YC separated and subjected to required recording signal processing, and then the tape head system 46
(Illustrated in FIG. 10).

Therefore, in the video signal transmission system 51 having the above-mentioned configuration, when the composite video signal of the Color plus system is recorded by the PAL system home VTR, the Color plus bit b ₅ is rewritten from "1" to "0". A color plus composite video signal can be obtained as a recording signal.

(Second Embodiment) A video signal transmission system 61 according to the present invention is a PAL system for composite video signals of the Color plus system.
When recording with a VTR for home use, the above-mentioned Color plus bit b ₅ except for the horizontal synchronizing signal and the color burst signal provided in the 23rd line of the Color plus composite video signal
The color plus type composite video signal is obtained by muting the ID area including at least the pedestal level (black level). That is, the video signal transmission system 61 according to the present invention is, as shown in FIG. 2, a VTR 41 (shown in FIG. 10) of a Colorplus type composite video signal (a signal shown in FIG. 3A at a point A in the figure). When recording via the recording system shown in the figure, signal processing for previously muting the ID area (“ID” portion shown in FIG. 3A) provided in the 23rd line of the Color plus system composite video signal (ie, A configuration for performing a mute process in which the ID area ID existing in the period excluding the horizontal synchronizing signal and the color burst signal in the 23rd line of the color plus system composite video signal shown in FIG. , ID detection circuit 62, muting circuit 63).

Here, the ID detection circuit 62 is the second
When 3 lines are detected, the muting control signal is output. In response to the muting control signal, the muting circuit 63 substantially pedestalizes the above-mentioned ID area ID existing in the period excluding the horizontal synchronizing signal and the color burst signal in the 23rd line of the supplied Color plus system composite video signal. Colo that has been muted to the level
The composite video signal of the r plus system (the signal shown in FIG. 4 at point B in the figure) is output to the VTR recording system 55. VTR recording system 5
5 records the composite video signal supplied from the muting circuit 63 on the tape head system 46 after performing YC separation and performing the required recording signal processing.

Therefore, when the video signal transmission system 61 having the above-mentioned structure records the composite video signal of the Color plus system by the PAL system home VTR, the horizontal synchronizing signal provided in the 23rd line of the composite video signal of the Color plus system. A composite video signal of the Color plus system in which at least the ID area including the Color plus bit b ₅ described above is muted except for the color burst signal can be obtained as a recording signal.

The above-mentioned video signal transmission system 51, 61
The recording signals recorded by the tape head system 46 via the VTR recording system 55 by the Color Plus bit b ₅
Since the state does not exist "0" or Color plus bits b _5, above the recording signal VTR 41 (FIG. 10
The reproduction composite video signal reproduced in
Even if it is supplied to the plus type compatible TV receiver 31 (shown in FIG. 9), the reproduced composite video signal is not identified here as the Color plus system composite video signal, but is identified as the PAL system composite video signal. , A PAL system reproduced image based on luminance signals and color signals U and V obtained through the PAL system decoding circuit 33 without passing through the YC separation circuit 32 which is a three-dimensional comb filter for Color plus system decoding. A reproduced image can be obtained.

Therefore, even when the Color plus system composite video signal recorded and reproduced by the PAL system home VTR is supplied to the Color plus system compatible TV receiver 31, the Colo
By decoding as a composite video signal of the r plus system, it is possible to prevent the image quality from being greatly impaired, and it is possible to obtain a reproduced image that maintains at least the image quality of the PAL system reproduced image.

Now, the above-mentioned video signal transmission system 5
When the composite video signal of the Color plus system is recorded on the PAL system home VTR 1, 1 and 61 rewrite the Color plus bit b ₅ to "0", or perform signal processing without it. The video signal transmission system 71 described below rewrites the Color plus bit b ₅ ,
Alternatively, PAL is performed without performing signal processing that eliminates this.
The color plus system composite video signal recorded on the home VTR is reproduced on the PAL system home VTR and then the Color
The plus bit b ₅ is rewritten to “0” or signal processing for eliminating this is performed.

(Third Embodiment) As shown in FIG. 5, a video signal transmission system 71 according to the present invention has a luminance signal reproducing system 4 as shown in FIG.
7, color signal reproducing system 48 and synthesizing circuit 49 (all shown in FIG.
0) shown in FIG.
When outputting a composite video signal of the lor plus system, as described above, a large number of bits forming the ID area (the "ID" portion shown in FIG. 3A) provided in the 23rd line of the composite video signal of the Color plus system Among them, the configuration of performing signal processing (shown in FIG. 3B) for rewriting “1” to “0” in advance for the state of the Color plus bit b ₅ for identifying whether or not it is the Color plus system (that is, ID extraction) Circuit 52, discrimination circuit 53, ID
A rewriting circuit 54) is provided.

Here, the ID extracting circuit 73 uses the above-mentioned ID.
The processing is to extract the 23rd line in which a signal exists, and has the same configuration as the ID extracting circuit 52 (shown in FIG. 1) described above. Discrimination circuit 74 is Color plus bit b
_When it is determined that the state of ₅ is "1", the ID rewriting circuit 75
And outputs a rewrite control signal for rewriting the state of the Color plus bit b ₅ from "1" to "0", and has the same configuration as the above-mentioned discrimination circuit 74 (shown in FIG. 1). In response to this rewriting control signal, the ID rewriting circuit 75 changes the state of the Color plus bit b ₅ in the ID area provided in the 23rd line of the supplied Color plus system composite video signal from “1” to “0”. The ID rewriting circuit 75 (shown in FIG. 1) has the same configuration. In this way, the ID rewriting circuit 75 outputs the Color plus system composite video signal in which the state of the Color plus bit b ₅ is “0”.

Therefore, when the video signal transmission system 71 having the above-mentioned structure reproduces the composite video signal of the Color plus system from the PAL system home VTR, the Color plus bit b ₅
It is possible to output a composite video signal of the Color plus system in which "1" is changed to "0", and the PAL system home VT
Color plus system composite video signal reproduced in R
Even when it is supplied to the us system compatible TV receiver 31, it is possible to prevent the image quality from being greatly impaired by decoding as a composite video signal of this Color plus system, at least in the PAL system reproduction, as described above. It is possible to obtain a reproduced image that maintains the same image quality as the image. Of course, muting may be performed in the ID signal reproducing system as shown in FIG.

By the way, the color plus composite video signal reproduced from the VTR reproducing system 72 of the video signal transmission system 71 has a jitter (time axis fluctuation component), and as a means for removing this jitter. A video signal transmission system 81 according to the present invention described below uses a time base collector (TBC). VTR playback system 7
The composite video signal of the Color plus system, which is reproduced from No. 2 and from which the jitter is removed, exhibits substantially the same stability as the composite video signal of the Color plus system obtained by receiving and demodulating as a broadcast signal. And Color pl with the jitter removed
The composite video signal of the us system is supplied to the TV receiver 31 (shown in FIG. 9) compatible with the Color plus system described above.
The reproduced image obtained by decoding as the r plus type composite video signal is reproduced from the VTR reproduction system 72 and the jitter is not removed. The image quality is considerably improved as compared with the color plus type composite video signal similarly decoded. It will be a good thing.

A video signal transmission system 81 described later is a VT.
Composite video signal Colorplus scheme reproduced from R playback system 72 (Color plus bit b ₅ states are "0") jitter of composite video signal Color plus method obtained by removing at TBC of Color plus bit b ₅ The state is rewritten from "0" to "1".

(Fourth Embodiment) As shown in FIG. 6, a video signal transmission system 81 according to the present invention has a configuration of the video signal transmission system 51 (the configuration shown in FIG. 1, the ID extracting circuit 52, the discrimination circuit). The circuit 53, the ID rewriting circuit 54, the VTR recording system 55), the tape head system 46 (shown in FIG. 10), and the video signal transmission system 71 (the structure shown in FIG. 5, the VTR playback system 72, ID sampling circuit 7
3, a discrimination circuit 74, an ID rewriting circuit 75), a time base collector (TBC) 82, and a reference oscillator 83.
It has the same configuration as that of the above. The same components as those described above are designated by the same reference numerals, and the description thereof will be omitted. As a result, for example, in the next stage of the video signal transmission system 81, Co
By connecting a TV receiver 31 (shown in FIG. 9) compatible with the lor plus system, the TV receiver 31 outputs a color plus composite video signal (bit b ₅ is “1”) output from the video signal transmission system 81. State) is discriminated as a signal of the Color plus system, and thus the Y signal and the color signals U and V obtained by subjecting this composite video signal to YC separation processing by a three-dimensional comb filter.
The image corresponding to the primary color signals R, G, B based on
It is possible to receive images with the aspect ratio of. In addition, T
In the case of the VTR recording method in which it is decided to perform the BC processing, it is not necessary to rewrite b ₅ to “0” in the recording system and return it to “1” in the reproducing system.

[0040] Here, the composite video signal of the Color plus method (state of the Color plus bit b ₅ is "1") state of the input to the ID rewriting circuit 54 wherein the ID signal (bits b ₅₎ "1" To "0". Thus the ID
The rewriting circuit 54 is a color plus type composite video signal (Color
The state of plus bit b ₅ is “0”), which is output to the VTR recording system 55, where it is YC separated, subjected to the required recording signal processing, and then recorded on the tape head system 46. The reproduction signal reproduced from the tape head system 46 is the VTR reproduction system 7
After being supplied to No. 2 and subjected to required reproduction signal processing there, a Color plus composite video signal (the status of Color plus bit b ₅ is “0”) is output from this to the time base collector 82. The time base collector 82 inputs Colo
Colo obtained by removing the jitter of the r plus type composite video signal
It outputs a composite video signal of the r plus system,
Color input from the R playback system 72 and with jitter superimposed
After writing the plus-type composite video signal to an internal memory (not shown), the Colo memory stored in this internal memory
By reading the r plus system composite video signal with the clock pulse output from the crystal oscillator 83, the color plus system composite video signal from which jitter has been removed
Output to the rewriting circuit 75. The ID rewriting circuit 75 is a Colo from which the jitter is removed from the time base collector 82.
A composite video signal of the r plus system (the state of Color plus bit b ₅ is “0”) is input, and the state of this ID signal (bit b ₅ ) is rewritten from “0” to “1”. In this way, the ID rewriting circuit 54 can output the Color plus type composite video signal (the state of the ID signal (bit b ₅ ) is “1”).

By the way, a video signal of the PAL plus system, which is an EDTV system different from the above-mentioned composite video signal of the Color plus system, looks similar to that of the current TV receiver, while PAL pl
In the us system compatible TV receiver (aspect ratio 16: 9), the vertical resolution deterioration that occurs when receiving an image with the current TV receiver with an aspect ratio of 16: 9 is improved, and the definition of the video signal is improved. The encoded video signal on which the reinforcement signal for superimposing is superimposed is transmitted. Further, the ID signal (or the identification signal) is inserted in a predetermined line in order to specify the type and aspect ratio of the reinforcing signal on the receiving side.

For example, when the above-mentioned PAL plus system video signal is supplied to a PAL plus system compatible type TV receiver, the ID signal is detected by this TV receiver and the video signal is determined to be a PAL plus system video signal. Is displayed as a video signal in which the enhancement signal is demodulated from the video signal and vertical resolution deterioration of the video signal having an aspect ratio of 16: 9 is improved.

At this time, for example, when the video signal of the PAL plus system is recorded by the VTR recording system 55, the video signal and the ID signal inserted in a predetermined field of the video signal are recorded. . However, since the above-mentioned reinforcement signal is a signal not suitable for the recording processing of the VTR recording system 55 (the signal band is different), it is not transmitted as a signal that functions as a reinforcement signal. Therefore, for example, when the video signal recorded by the above-mentioned VTR recording system 55 is reproduced by the above-mentioned VTR reproducing system 72 and is supplied to such a TV receiver, this TV receiver will
Since the ID signal is detected from the supplied video signal and the video signal is determined to be the PAL plus system video signal, demodulation processing of the reinforcing signal is performed. However, when the reinforcement signal demodulation processing is performed on the reproduced video signal, the above-mentioned signal component that does not function as the reinforcement signal is transformed (for example, distorted) and transmitted, so that, for example, the video signal is displayed on the display screen. It is not displayed normally on the top, and there is a hindrance in viewing (such as screen disorder). Therefore, there is a problem in that the usability is not good such that the user mistakes the disorder on the display screen for a failure.

(Fifth Embodiment) Therefore, when a high-definition TV receiver 91 used in the video signal transmission system according to the present invention for solving the above-mentioned problem is received (1) when a PAL plus type video signal is received, 2) When the video signal reproduced from the current VTR is supplied to the input terminal, (3) When the video signal reproduced from the current VTR is received as a high frequency (RF) signal, (4) PAL plus compatible A case where a video signal is supplied to the input terminal from an external device such as a decoder will be described.

First, the high-definition TV receiver 91 according to the present invention.
As shown in FIG. 11, according to channel information set by the user, for example, a receiving unit (tuner) 92 for receiving the above-mentioned PAL plus system video signal and the current PAL system composite video signal, the current VTR. A first changeover switch (first changeover switch (first changer) for changing over and outputting any one of the input terminal 93, the tuner 92 or the video signal supplied from the input terminal 93 to which a video signal output from Switching means) 94, the identification signal detection means 95 for detecting the identification signal inserted in the video signal from the output result of the first changeover switch 94 and outputting the control signals 95a and 95b based on this, the video signal by the control signal 95a. Demodulation processing means 9 for demodulating the reinforcement signal superimposed on
6, a second changeover switch (second changeover means) 97 and a control signal 95b for selectively outputting either the video signal supplied from the demodulation processing means 96 or the first changeover switch 94 according to input selection information described later. The selection switching means 98 for switching a predetermined aspect ratio and signal format to the output result of the second changeover switch 97, and the video signal switched to the predetermined aspect ratio and signal format by the selection switching means 98 are displayed. It is composed of CRT99.

(1) The case where a PAL plus type video signal is received will be described. The tuner 92 receives the video signal of the PAL plus system according to the channel information set by the user, and the first changeover switch 94 switches and outputs the video signal output from the tuner 92 according to the input selection information. The input selection information described above is simultaneously supplied to the second changeover switch 97. Here, the input selection information is, for example, a selection instruction specified by a user through an operation unit (not shown) in order to select a broadcast signal received by the tuner 92 and a video signal from an external device supplied to the input terminal 93. Information. That is, when the user views the broadcasted video signal, the tuner 92 is selected by this input selection information, and the channel of a predetermined broadcast (current broadcast or broadcast by the PAL plus system) is set (channel information).

The PAL plus type video signal output from the tuner 92 is supplied from the first changeover switch 94 to the identification signal detecting means 95, the demodulation processing means 96 and the second changeover switch 97, respectively. The identification signal detection means 95
The identification signal inserted in the video signal of the PAL plus system is detected and the control signal 95a is supplied to the demodulation processing means 96.
At the same time, the identification signal detecting means 95 causes the selection switching means 9
8 to the control signal 95b.

The control signal 95a is, for example, a signal having a value of "Hi" when the identification signal detecting means 95 detects the identification signal, and conversely, "Lo" when the identification signal is not detected.
Is a signal that becomes the value of. This time, the demodulation processing means 96 is supplied with the PA by the control signal 95a having the value of "Hi".
Demodulates the reinforcement signal that is superimposed on the L plus video signal. The PAL plus system video signal from which the reinforcement signal has been demodulated is subjected to a process in which the definition of the display image is improved in a predetermined aspect ratio, and is supplied to the second changeover switch 97.

The second changeover switch 97 operates the demodulation processing means 9 according to the above-mentioned input selection information and channel information.
The video signal of the PAL plus system supplied from 6 is switched and output to the selection switching means 98 in the next stage. The selection switching means 98 switches the aspect ratio of the PAL plus type video signal based on the control signal 95b. This aspect ratio switching may be performed, for example, by selecting the voltage value of the deflection coil that adjusts the effective display area of the display screen preset according to the value of the control signal 95b, or by voltage control based on the control signal 95b. . In this case, the PA where the augmented signal was demodulated
The video signal of the L plus system is switched to the aspect ratio of 16: 9 and supplied to the CRT 99. The PAL plus type video signal displayed in this aspect ratio on the CRT99 has the enhanced definition (in this case, vertical scanning line resolution) of the display image because the reinforcement signal is demodulated, and a high-quality video signal is obtained. Can be displayed.

(2) The time when the video signal reproduced from the current VTR is supplied to the input terminal will be described. At this time, the user selects an external input, and according to the input selection information corresponding thereto, the first changeover switch 94 switches and outputs the video signal output from the input terminal 93. The input selection information described above is simultaneously supplied to the second changeover switch 97.

The video signal output from the input terminal 93 is
From the first changeover switch 94 to the identification signal detecting means 95,
It is supplied to the demodulation processing means 96 and the second changeover switch 97, respectively. The identification signal detection means 95 detects the identification signal inserted in the video signal, supplies the control signal 95a to the demodulation processing means 96, and at the same time supplies the control signal 95b to the selection switching means 98.

Demodulation processing means 96 by the control signal 95a
Performs the above-mentioned processing for demodulating the augmented signal on the video signal supplied from the first changeover switch 94. In this case, the augmented signal component is modified by passing through the current VTR as described above. Since the image signal output from the demodulation processing means 96 is visually disturbed, the second changeover switch 97 receives the image signal. Supplied.

The second changeover switch 97 described above interlocks with the changeover of the first changeover switch 94 according to the input selection information, and changes over and outputs the video signal directly supplied from the first changeover switch 94. Therefore, the input terminal 93
The video signal supplied from is switched and output to the selection switching means 98 without demodulating the reinforcing signal which has become a noise component even if the identification signal is detected.

The selection switching means 98 uses the control signal 95 described above.
The aspect ratio of the video signal is switched to a predetermined 16: 9 by b, and is output to the CRT 99. In this way, in the video signal including the identification signal but the reinforcement signal does not function normally, the visual disturbance of the video signal can be prevented by displaying it on the CRT 99 without interference by the demodulation processing of the reinforcement signal.

(3) The time when the video signal reproduced from the current VTR is received as a radio frequency (RF) signal will be described. At this time, for example, since the video signal supplied from the VTR is supplied to the tuner 92, the above processing (1) is performed, and the video signal is visually disturbed by the demodulation processing of the reinforcing signal that does not function normally. Will occur. Therefore, for example, the input selection information may be set so that the processing of (2) is performed in a specific channel for outputting the video in the tuner 92 (for example, the tuner 9).
When the video signal received by 2 is the video signal of the current broadcast, the first switching means may be switched and controlled according to the channel information).

(4) A case where a video signal is supplied to an input terminal from an external device such as a decoder compatible with the PAL plus system will be described. Since the video signal is supplied from the external device through the input terminal, the processing of (2) above is performed, and the demodulation processing of the reinforcement signal is not performed even if the video signal includes the identification signal and the normal reinforcement signal. In the predetermined aspect ratio, the processing for improving the definition of the displayed image is not performed. Therefore,
At this time, for example, by separately providing an input terminal, the current V
The terminal for connecting the TR and the terminal for connecting the above-mentioned high-definition video signal decoder (or VTR or the like compatible with the PAL plus system) are distinguished, and the video signal supplied from the terminal for connecting the decoder is the above ( It may be set so as to perform the processing of 1).

In the fifth embodiment described above, the switching control of the second changeover switch 97 is controlled by the input selection information and the channel information specified by the user, but the output of the first changeover switch 94 is controlled. Reinforcement signal detection means for detecting whether or not the reinforcement signal is present in the signal is newly provided, and based on the detection result, the first and the first
The two changeover switches 94 and 97 may be controlled.
That is, even if the identification signal is superposed on the output signal of the first changeover switch 94, the second changeover switch 97 reads "the high-definition TV receiver via the existing broadcasting system recording / reproducing apparatus". If it is a signal that is not suitable for transmission to, the high-quality image reception processing is not performed.

[0058]

As described above, the video signal transmission system according to the present invention is a video signal transmission system for transmitting a series of high-definition video signals based on the current broadcasting system to a high-definition TV receiver. When the high-definition video signal is a signal that is unsuitable for being transmitted to the high-definition TV receiver via the current broadcasting system recording / reproducing apparatus and is a signal having an identification signal indicating that it is a high-definition video signal, When the high-definition video signal is recorded or reproduced by using the current broadcasting system recording / reproducing apparatus, a rewriting unit is provided for rewriting the identification signal so as not to indicate that the high-definition video signal is provided, and the current broadcast during reproduction is provided. System recording / reproducing device to the high-quality TV
The high-definition video signal transmitted to the receiver is transmitted to the high-definition TV.
Since the receiver is configured not to perform high-quality image receiving processing, for example, Co recorded and reproduced by a PAL system home VTR
Even when the composite video signal of the lor plus system is supplied to the TV receiver 31 compatible with the Color plus system, by decoding the composite video signal of the Color plus system, it is possible to prevent the image quality from being greatly impaired, and at least PAL.
It is possible to obtain a reproduced image that maintains the image quality equivalent to that of the system reproduced image.

Further, the video signal transmission system according to the present invention is the video signal transmission system having the above-mentioned configuration, wherein the time axis fluctuation component is removed from the high quality video signal reproduced from the current broadcasting system recording / reproducing apparatus. And a changing means for changing the identification signal of the high-definition video signal supplied from the removing means to a signal indicating that the high-definition video signal is a high-definition video signal. From the high-definition video signal reproduced from the current broadcasting system recording / reproducing apparatus that performs high-definition image reception processing on the high-definition video signal transmitted from the high-definition TV receiver to the high-definition TV receiver. Removing means for removing the component, and converting the identification signal of the high-definition video signal supplied from the removing means into a signal indicating that the high-definition video signal is a high-definition video signal. And a high-definition video signal to be transmitted from the high-definition TV receiver to the high-definition TV receiver by the high-definition TV receiver. The color plus system composite video signal from which the jitter is removed after being reproduced from the system 72 is a Co signal obtained by being received and demodulated as a broadcast signal.
Since it exhibits almost the same stability as the lor plus system composite video signal, the color plus system composite video signal from which jitter has been removed is compatible with the Color plus system TV receiver 31 (shown in FIG. 9). The reproduced image obtained by decoding it as a composite video signal of the Color plus system is reproduced from the VTR reproduction system 72 and jitter is not removed.
This can be obtained as an image of which image quality is considerably improved as compared with that obtained by similarly decoding the composite video signal of the lor plus system.

Furthermore, the video signal transmission system according to the present invention is a high-definition TV receiver used in a video signal transmission system for transmitting a series of high-definition video signals based on the current broadcasting system to a high-definition TV receiver. Receiving means for receiving the high-quality video signal, a video signal supplied from an external device,
First switching means for switching and outputting a high-quality video signal output from the receiving means, and an identification signal indicating a high-quality video signal is detected from the video signal output from the first switching means. , A reinforcement signal demodulation means for performing high-quality image reception processing based on this, the video signal supplied from the first switching means, and the high-quality video signal based on the detection result of the identification signal. A second switching means for switching and outputting the processed video signal subjected to the high-quality image receiving processing, wherein the second switching means receives the high-quality TV image for the video signal via a recording / reproducing apparatus of a current broadcasting system. If the signal is an unsuitable signal to be transmitted to the machine and has a discrimination signal indicating that it is a high-quality video signal, at least a video signal not subjected to high-quality image receiving processing is switched and output. Takara, for example, of the video signal including an identification signal, a horizontal due to change the aspect ratio of the display screen,
For a video signal in which the reinforcement signal for improving the definition of vertical resolution is not superimposed in a normal state, a video signal that is not subjected to the reinforcement signal demodulation processing described above is output, and a video signal in which the reinforcement signal is normal is output. By outputting the video signal that has undergone this reinforcement signal demodulation processing, the video signal can be displayed without any visual disturbance on the display screen with a relatively simple configuration, so it is compatible with high-quality video signals. This has the effect of improving the usability of the TV receiver and the current VTR.

[Brief description of drawings]

FIG. 1 is a block diagram of a first embodiment of a video signal transmission system according to the present invention.

FIG. 2 is a block diagram of a second embodiment of a video signal transmission system according to the present invention.

FIG. 3 is a waveform diagram for explaining the operation of the video signal transmission system.

FIG. 4 is a waveform diagram for explaining the operation of the video signal transmission system.

FIG. 5 is a block diagram of a third embodiment of a video signal transmission system according to the present invention.

FIG. 6 is a block diagram of a fourth embodiment of a video signal transmission system according to the present invention.

FIG. 7 is a block diagram of a Color plus type encoder.

FIG. 8 is a block diagram of a Color plus type decoder.

[Figure 9] Color plus compatible TV that can determine the reception mode
It is a block diagram of a receiver.

FIG. 10 is a block diagram of a PAL home VTR.

FIG. 11 is a block diagram of a high-definition TV receiver which is a fifth embodiment of the video signal transmission system according to the present invention.

[Explanation of symbols]

 31, 91 TV receiver (high-definition TV receiver) 41 VTR (current recording / reproducing apparatus for broadcasting system) 51, 61, 71, 81 Video signal transmission system 54 ID rewriting circuit (rewriting means) 63 Muting circuit 75 ID rewriting circuit (Changing means) 82 TBC (Removing means)

Claims (3)

[Claims] 1. A video signal transmission system for transmitting a series of high-definition video signals based on a current broadcasting system to a high-definition TV receiver, wherein the high-definition video signal is transmitted through the current broadcasting system recording / reproducing device. When the signal is an unsuitable signal to be transmitted to a quality TV receiver and is provided with an identification signal indicating that it is a high quality video signal, the high quality video signal using the current broadcasting system recording / reproducing apparatus. A recording means for rewriting the identification signal so as not to indicate that the signal is a high-definition video signal at the time of recording or reproduction, and transmitting from the current broadcasting system recording / reproducing apparatus to the high-definition TV receiver during reproduction. A video signal transmission system characterized in that a high-quality video signal is not processed by the high-quality TV receiver. 2. The video signal transmission system according to claim 1, wherein the removing means removes a time-axis fluctuation component from the high-definition video signal reproduced from the current broadcasting system recording / reproducing apparatus. Changing means for changing the identification signal of the supplied high-definition video signal to a signal indicating that the high-definition video signal is a high-definition video signal, and transmitting from the changing means to the high-definition TV receiver A high-definition video signal is transmitted to the high-definition video signal by the high-definition TV receiver. 3. A high-definition TV receiver for use in a video signal transmission system for transmitting a series of high-definition video signals based on the current broadcasting system to a high-definition TV receiver, the receiving means receiving the high-definition video signal. A first switching means for switching and outputting a video signal supplied from an external device and a high-quality video signal output from the receiving means; and a high-quality video signal output from the first switching means. An auxiliary signal demodulating means for detecting an identification signal indicating that it is a video signal and performing high-quality image receiving processing based on the identification signal, the video signal supplied from the first switching means, and the identification signal are detected. A second switching means for switching and outputting a processed video signal obtained by performing high-quality image receiving processing on the high-quality video signal based on the result; Person At least high-quality image reception processing is performed when the signal is unsuitable for transmission to the high-definition TV receiver via the recording / reproducing device and has a discrimination signal indicating that it is a high-definition video signal. A high-definition TV receiver characterized by switching and outputting non-existing video signals.