JPH04373293A - Television signal transferring method - Google Patents

Abstract

PURPOSE:To obtain a picture of good quality by separating a picture of a wide aspect into a center panel part and a side panel part and multiplexing a low frequency signal of a YIQ signal of the side panel part into a horizontal, an overscanning and a blanking parts. CONSTITUTION:A signal separating circuit 150 separates a video signal of a wide aspect, aspect ratio 16:9, into signals of a center panel part and a side panel part, and a time axis of the signal of the center panel part is elongated by a time axis elongating circuit 151. Mean while, the signal of the side panel part is inputted to a frequency separating circuit 152 so as to be separated into a low frequency signal and a high frequency signal, and the low frequency signal is compressed in terms of a time axis by a time axis compressing circuit 153. The compressed low frequency signal of the side panel part is multiplexed in frequency into a horizontal overscanning part and a horizontal blanking part of the center panel part by a frequency multiplexing circuit 155. Thus, preventive factors such as a cross-color, a cross-luminance, etc., are reduced.

Description

[Detailed description of the invention]

0001

[Field of Industrial Application] The present invention relates to a television signal transmission system, and particularly to a second generation EDTV (Extended Definition TV) that is compatible with current television systems.
tion TV) transmission system.

0002

[Prior Art] Conventionally, as a method for transmitting video signals with an aspect ratio larger than 4:3 while maintaining compatibility with the NTSC system, the top and bottom of the NTSC image are blackened, and vertical and horizontal high frequencies are added to the blackened areas. A letterbox method that transmits signals by superimposing them, and a side panel method that separates the center and side signals of a wide image and multiplexes the signals from both sides into vertical and horizontal blanking periods and orthogonal components of the video carrier wave. etc., and intermediate methods between these two have been proposed.

0003

[Problem to be solved by the invention] As mentioned above, NTSC
In the letterbox method, which blackens the top and bottom of the image and multiplexes various signals such as high-frequency signals into those areas, the current N
When played back on a TSC receiver, a black tint appears at the top and bottom of the screen, making it unsightly.

On the other hand, the center part and side part of a wide image are separated, the low range of the Y signal of the side part is multiplexed to the horizontal overscan part, and the high range of the Y signal of the side part and the IQ signal are multiplexed. In the side panel method, which multiplexes and transmits signals to the three-dimensional hole in the center panel, signals including low frequencies of DC to 1.5 MHz for I signal and DC to 0.5 MHz for Q signal are multiplexed to the three-dimensional hole of the center panel. Therefore, there is a problem in that the low-frequency parts of the I and Q signals, which have particularly large energy, cause a large interference with clock color and cross luminance on the current NTSC system receiver.

[0005]

[Means for Solving the Problems] In order to solve the above problems, the present invention provides a side panel image in a television signal transmission system in which a wide aspect image is separated into a center panel image and a side panel image and transmitted. Y of panel part
a frequency separation means for frequency-separating the IQ signal into low frequency and high frequency; a first time-axis compression means for time-axis compressing the low-frequency signal YIQ of the side panel section; A first multiplexing means for frequency multiplexing the horizontal overscan section and the horizontal blanking section of the video signal of the center panel section is provided.

[0006]

[Function] According to the above configuration, a wide aspect image is separated into a center panel part and a side panel part, and the low frequency signal of the YIQ signal in the side panel part is not displayed on the screen in the horizontal overscan part and horizontal blanking part. Since the center panel section is multiplexed, there are no components that interfere with cross color or cross luminance in the center panel section, and a high quality image can be obtained.

[0007]

DESCRIPTION OF THE PREFERRED EMBODIMENTS FIG. 1 is a block diagram showing the configuration of essential parts of an embodiment of the present invention. In Figure 1, 100 is the number of scanning lines 5
25 lines, aspect ratio 16:9, interlace ratio 2:
1 is a wide camera, 150 is a signal separation circuit that separates a wide aspect video signal with an aspect ratio of 16:9 into signals for the center panel section and side panel section, and 151 is a timer for extending the time axis of the signal for the center panel section. 152 is a frequency separation circuit that separates the signal from the side panel section into a low frequency signal and a high frequency signal; 153 is a time axis compression circuit that compresses the time axis of the low frequency signal from the side panel section. .

154 is a time axis expansion circuit that extends the time axis of the high frequency signal of the side panel section; 155 is a time axis expansion circuit that extends the time axis of the high frequency signal of the side panel section; 155 is the horizontal overscan section and horizontal blanking section of the video signal of the center panel section; 126 is a frequency multiplexing circuit for frequency multiplexing the high-frequency signal of the side panel section into the horizontal overscan section of the video signal of the center panel section and the three-dimensional hole of the horizontal blanking section; 137; is the output terminal.

The configuration of the essential parts of one embodiment of the present invention is as described above, and this is shown in more detail as shown in FIG. In FIG. 2, the same parts as in FIG. 1 are denoted by the same reference numerals, and the description thereof will be omitted. In FIG. 2, 101, 102, 103 are A/D converters that convert RGB signals from the wide camera 100 into digital signals, 104 is a matrix conversion circuit that converts RGB signals to YIQ signals, and 105 is 0 (DC) to 1.
．． horizontal low-pass filter (hereinafter referred to as "H-LPF") for the I signal in the center panel section with a band of 5 MHz;
Reference numeral 106 denotes an H-LPF for the low-frequency I signal of the side panel section having a band of 0 to 0.5 MHz.

[0010] 107 is an H-LPF for the Q signal of the center panel section having a band of 0 to 0.6 MHz, and 108 is a 0 to 0
．． H-LPF for the low-frequency Q signal of the side panel section with a band of 2 MHz, 109 is an H-LPF of the Y signal of the center panel section that has a band of 0 to 5.0 MHz, and 110 is 0 to 5.0 MHz.
111 is a horizontal band pass filter (hereinafter referred to as a (referred to as "H-BPF"), 129 is 0
．． H-BPF of the high frequency I signal of the side panel section with a band of 5 to 1.5 MHz, 130 is 1.4 to 5.0 MHz
H-BP of the high frequency Y signal of the side panel section with a band of
It is F.

Further, 112, 114 and 116 are time axis expansion circuits that expand the time axis of the IQY signal of the center panel section by 1.2674 times, and 113 and 115 are time axis expansion circuits that expand the time axis of the IQY signal of the side panel section by 3 times. 117 and 118 are time axis compression circuits that compress the low frequency Y signal and high frequency Q signal of the side panel section by three times, respectively. 131 and 132 are the high frequency compression circuits of the side panel section. This is a time axis expansion circuit that expands the time axis of the IY signal in the area by three times.

119, 120 and 121 are splicers for splicing the center panel signal and the low frequency side panel signal in each IQY signal; '' A modulator that modulates with carrier waves (so-called open carriers) that are in the first and third quadrants of the two-dimensional frequency spectrum and have a conjugate relationship with the color subcarrier. 133 is a high-frequency signal of the I signal of the side panel section. a modulator for modulating with the above-mentioned atrium carrier, 13
Reference numeral 4 denotes a modulator that modulates the high frequency signal of the Y signal of the side panel portion with a carrier wave having a phase different by 90 degrees from the above-mentioned atrium carrier.

123 is the splicer 119 and 12 mentioned above.
124 is a modulator that orthogonally modulates the output of 0 with a color subcarrier of 3.58 MHz, and 124 is a modulator in which the modulation signal of the high-frequency Q signal of the side panel section is frequency-multiplexed into the three-dimensional hole of the horizontal overscan section and the horizontal blanking section. An adder 125 adds the modulated signal of the high frequency Q signal to the IQ modulated signal so that the Y signal from the splicer 121 is added to the output of the adder 124.
126 is an adder for frequency multiplexing signals; 136 is an adder for adding the modulation signal of the high-frequency Y signal of the side panel section to the modulation signal of the high-frequency I signal of the side panel section obtained through the inverse Nyquist filter 135; An adder that multiplexes the output of the adder 136 onto the center panel signal obtained from the adder 125; 127 an adder that adds a synchronization signal to the video signal of the adder 126; 128 an adder 12;
7 is a D/A converter that converts a television signal to which a synchronization signal is added into an analog signal.

The embodiment of the present invention has the above configuration, and its operation will be explained below. In FIGS. 1 and 2, RGB signals output from a wide camera 100 with 525 scanning lines/16:9 aspect ratio/2:1 interlace ratio are converted into digital signals by A/D converters 101, 102, and 103. After that, the matrix converter 104 converts the signal into a luminance signal Y and color signals I and Q. In this, the center panel part of the Y signal is band-limited to DC ~ 5.0 MHz by the H-LPF (horizontal low-pass filter) 109, and then the original image (a) as shown in (b) and (c) of FIG.
The time axis of the center panel section (b) is expanded by a factor of 1.2674 by the time axis expansion circuit 116, resulting in a signal as shown in FIG. 3(c).

[0015] Also, the low frequency of the side panel part of the Y signal is H.
- After being band-limited to DC ~ 1.4 MHz by the LPF 110, the original image (a
The side panel portion (d) of ) is compressed three times in time by the time-base compression circuit 117, resulting in a signal as shown in FIG. 3(e). This compressed signal (e) is arranged in the horizontal overscan part and the horizontal blacking part of the video signal, and is spliced with the center panel part (c) of the expanded Y signal in the splicer 121, and (g) in FIG. ) will result in a signal as shown. In this case, the signal (e) is superimposed using the 1.60 μs portions on the left and right sides of the horizontal overscan portion, and as shown in FIG. This is done using 0.67 μs each for the left and right sides, which does not affect the burst signal.

Next, the center panel portions of the I signal and Q signal are band-limited by the H-LPFs 105 and 107, respectively, to DC to 1.5 MHz for the I signal and DC to 0.6 MHz for the Q signal. Similar to the center panel portion of the signal, the center portion (b) of the original image (a) is expanded by 1.2674 times by the time axis expansion circuits 112 and 114, as shown in FIGS. 3(b) and 3(c). The signal will be as shown in 3(c). In addition, the side panel portion of the IQ signal is reduced by H-LPF106 and 108, respectively, and the I signal is
After band-limiting the C ~ 0.5 MHz and Q signals to DC ~ 0.2 MHz, the original image ( The side panel portion (d) of a) is compressed three times by the time axis compression circuits 113 and 115, resulting in a signal as shown in FIG. 3(e).

The low frequency signal (e) of the side panel section of the compressed IQ signal is placed in the horizontal overscan section and horizontal blanking section of the video signal, and is processed by splicers 119 and 120, respectively, as shown in FIG. 3(g). As shown in FIG. 3, after being connected to the center panel portion of the expanded IQ signal, the signal is orthogonally modulated by a 3.58 MHz color subcarrier in a modulator 123. In addition, the high frequency range of the Q signal in the side panel section is handled by H-BPF (horizontal band pass filter) 11.
1, the signal is limited to a band of 0.2 MHz to 0.5 MHz, and then compressed three times in the time axis compression circuit 118.

The compressed high frequency signal of the Q signal of the side panel section is input to the modulation circuit 122.
So, on the “time-vertical” two-dimensional frequency spectrum, the first
The carrier wave in the quadrant and the third quadrant and having a conjugate relationship with the color subcarrier, that is, the so-called open-air carrier, is the Q of the side panel section above.
Modulates the high frequency signal of the signal. The high frequency modulation signal of the Q signal of the side panel section is added to the IQ modulation signal in an adder 124, and then frequency multiplexed with the Y signal in an adder 125.

Next, with respect to the YI high-frequency signal of the side panel section, the I signal is filtered from 0.5 MHz to 1
．． After the 5MHz, Y signal is band-limited to 1.4MHz to 0.5MHz, the time axis is expanded three times by time axis expansion circuits 131 and 132, and the signal (d) in FIG. 3 becomes the signal (f).
become. Next, the modulation circuits 133 and 134 modulate the high-frequency signal of the Y signal of the side panel section with the above-mentioned atrium carrier, and further modulate the high-frequency signal of the I signal of the side panel section with a carrier wave that is 90 degrees out of phase with the above carrier wave. do. The modulation signal of the side panel part I signal is filtered by an inverse Nyquist filter 13.
After the band is limited by 5, the signal is added to the modulation signal of the Y signal of the side panel section in an adder 136.

The addition signal of the adder 136 is sent to the adder 12.
At step 6, the signal of the center panel section, that is, the horizontal overscan section and the horizontal blanking section, is multiplexed with a signal obtained by multiplexing the low frequency signal of the YIQ signal and the high frequency signal of the Q signal of the side panel section, and is multiplexed by an adder 127. A synchronizing signal is added to the signal, which is converted into an analog signal by the D/A converter 128 and output from the output terminal 137. The characteristics, compression/expansion coefficients, etc. of the various filters mentioned above are merely examples.
It is not necessarily limited to the above numerical values.

[0021]

[Effects of the Invention] Since the present invention has the above configuration,
While maintaining compatibility with the NTSC system, it is possible to transmit wide aspect images within the NTSC transmission band, and it also eliminates the side panel part, which causes major interference to current receivers in the signals multiplexed to the 3D hole. Since the low frequency signal of the YIQ signal is multiplexed into the horizontal overscan section and the horizontal blacking section, interferences such as clock color and cross luminance can be significantly reduced compared to current receivers.

[Brief explanation of the drawing]

FIG. 1 is a block diagram showing the main configuration of an embodiment of the present invention.

FIG. 2 is a block diagram of an embodiment of the present invention.

FIG. 3 is an explanatory diagram of the operation of the embodiment of the present invention.

FIG. 4 is an explanatory diagram of the operation of the embodiment of the present invention.

[Explanation of symbols] 105 to 110 H-LPF 111, 129, 130 H-BPF 113, 115
, 117, 153 Time axis compression circuit 125 Adder 131, 132, 154 Time axis expansion circuit 150
Signal separation circuit 152 Frequency separation circuit

Claims (2)

[Claims] Claim 1: In a television signal transmission system that separates a wide aspect image into an image of a center panel portion and an image of a side panel portion and transmits the same, the YIQ signal of the side panel portion is frequency-separated into low and high frequencies. frequency separation means, time axis compression means for time axis compressing the low frequency signal YIQ of the side panel section, and horizontal overscanning section and horizontal blanking of the video signal of the center panel section by converting the low frequency signal YIQ of the side panel section into a horizontal overscan section and a horizontal blanking section of the video signal of the center panel section. 1. A television signal transmission system, comprising: first multiplexing means for frequency multiplexing the frequencies of the television signal transmission system. 2. Further, time-base compression means for time-base compressing at least a part of the high-frequency signal of the side portion, and a horizontal overscan unit and horizontal blanking unit for compressing the high-frequency signal output from the time-base compression means. 2. The television signal transmission system according to claim 1, further comprising means for frequency multiplexing in a three-dimensional hole in the area.