JPH10257343A - Television receiver and television signal transmitting/ receiving method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a television receiver with which video signals having different numbers of effective scanning lines can be displayed, without distorting an image when these signals are received. SOLUTION: For a television receiver provided with receiving means 1, 4 and 7 for receiving the television signals of a prescribed system, monitor (CRT) for displaying the video signals demodulated by these receiving means 1, 4 and 7 and a deflection circuit part 9 for scanning this monitor based on synchronization information contained in these video signals, an identification signal- separating circuit 10 is provided for detecting an identification signal which shows effective horizontal video line information of video signals and by switching the vertical deflection sensitivity of the deflecting circuit part 9 based on the detecting signal of this identification signal separating circuit 10, even when the number of effective scanning lines is changed, the image on the monitor is prevented from being omitted or made distorted.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a television receiver for receiving and displaying a video signal, and a method for transmitting and receiving a television signal.

[0002]

2. Description of the Related Art Television signals are generally transmitted from a broadcasting station by terrestrial waves and received by a television receiver at home. In recent years, CATV transmitted by a cable other than terrestrial waves, satellites by satellites, and the like. Broadcasting has also been realized.

[0003] Satellite broadcasting uses an extremely high broadcast wave (GHz), and a high-definition video transmission system for transmitting a video signal with higher definition has been realized. For example, a high-definition signal has 1125 horizontal scanning lines.
By adopting the MUSE system, a signal with a video band of 20 MHz can be transmitted using a frequency band of approximately 8 MHz, and it is a medium for transmitting video information with higher density than before.

[0004]

In recent years, media (graphic images) created by a computer as video information has been increasing, and when such a computer graphic screen is transmitted as a high-definition video signal, the image of the computer graphics screen must be increased. May be a problem. For example, in a high-definition (hereinafter, also referred to as HD) system, there are 1125 horizontal scanning lines, the number of effective horizontal lines (the number of horizontal lines on which video signals are actually carried) is 1035, and the aspect ratio is 16:16. 9 is set. As described above, the image screen of the HD system has a wider display screen than that of the conventional television system, so that the number of pixels in the horizontal direction of the HD screen is also increased, for example, to 1920 dots.
Therefore, the shape of one pixel becomes a horizontally long shape, and an image that does not match the shape of the pixel on the computer graphic (CG) screen is obtained.

Therefore, it has been considered that the number of effective scanning lines of the video signal of the HD system is changed from 1,035 to 1,080 so that the CG screen and the HD screen can be made as consistent as possible. When an HD signal having 1080 effective scanning lines is received when the monitor is set to display 1080 effective scanning lines as shown in FIG. However, the image is displayed at the center, but when an HD signal having an effective scanning line number of 1035 is received, the upper part of the monitor screen is displayed as being chipped, and the center of the image is shifted upward. The screen looks like this. Conversely, when an HD signal having 1080 effective scanning lines is received from a monitor having 1035 effective scanning lines, the received image is displayed as shown in FIG. There is a problem that a non-image portion Dx is generated at the upper portion, and a screen is formed such that the center portion of the image is biased downward.

[0006]

SUMMARY OF THE INVENTION In order to solve the above-mentioned problems, the present invention provides a receiving means for receiving a television signal of a predetermined system, and a monitor for displaying a video signal demodulated by the receiving means. Means for detecting an identification signal indicating effective video line information of said video signal in a television receiver comprising means for deflecting said monitor means based on synchronization information contained in said video signal. A signal detecting means is provided, and the vertical deflection sensitivity of the deflecting means is changed based on the detection signal of the identification signal detecting means to switch the size in the vertical direction. According to a second aspect of the present invention, the number of effective scanning lines of the HD video signal is inserted as a discrimination signal into a horizontal line in a vertical blanking period and transmitted, and the discrimination signal of the video signal is detected on a receiving side and monitored. A vertical signal sensitivity (size) of the apparatus is automatically set in accordance with the number of effective scanning lines.

Since identification information indicating the number of effective horizontal lines is inserted in the vertical blanking period of the video signal, the sensitivity of the vertical deflection system is automatically switched by detecting this information on the receiving side, and the effective horizontal line is switched. Even when the number of lines changes, the image can be positioned at the center of the monitor screen.

[0008]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment in which a television receiver of the present invention uses an HD system will be described below with reference to FIG. In this figure, reference numeral 1 denotes a parabolic antenna and a converter for receiving a radio wave transmitted from a satellite station, the output of which is represented by B as a first intermediate frequency.
It is supplied to the S tuner 2. The channel frequency selected by the BS tuner 2 is transmitted to the MU via the A / D converter 3.
The signal is supplied to the SE signal processing unit 4, the audio decoder 5, and the synchronization signal separation circuit 6.

The MUSE signal processing unit 4 converts the extracted HD signal into a sub-sampling frequency, and performs inter-frame internal interpolation processing, inter-field internal interpolation processing, and the like based on the motion detection information. Then, the signal is converted to TCI (Ti
The signal is converted into a component video signal via a video signal processing unit 7 having a circuit such as a “me Compressed Integreation” circuit and a gamma correction circuit, and is supplied to a monitor such as a CRT.

The audio decoder 5 includes a data ternary-binary conversion and expansion circuit, and converts an audio signal transmitted as PCM data into an analog stereo signal or a bilingual language. Further, a timing signal for performing various signal processing based on the synchronization information separated by the synchronization signal separation circuit unit 6 is output from the timing generation circuit 8, and a part of the timing signal is supplied to the deflection circuit 9.

The above-mentioned receiving circuit is known as an HD television receiver and its detailed description is omitted. In the case of the present invention, however, in the case of the present invention, the synchronizing signal separating circuit unit 6 is provided with a video signal to be described later. An identification signal separation circuit section 10 for separating the inserted identification signal is provided, and the deflection sensitivity (size) of the vertical deflection system of the deflection circuit section 9 is set based on the output of the identification signal separation circuit section 10. It is configured to be. That is, the circuit extracts the identification signal indicating the number of effective horizontal lines of the video signal, and sets the vertical deflection sensitivity for scanning the monitor.

FIG. 2 shows the scanning range of the electron beam in the vertical direction of the picture tube CRT. The center of deflection of the beam with respect to the tube surface S is P, and the display range of the tube surface S is ab. In this case, the vertical scanning angle with respect to the number of effective scanning lines indicates W. When the number of effective scanning lines is 1035, the vertical deflection angle θ35 in one horizontal period is W / 1035,
When the number of effective scanning lines is 1080, the same scanning angle W
In this case, the deflection angle θ80 may be set to be W / 1080. In other words, when the video signal of 1080 effective scanning lines is received when the deflection angle is set based on 1035 lines, the vertical deflection angle (deflection sensitivity) per line is 1035/1080. By doing so, the above-mentioned problems can be solved.

The automatic switching of the deflection sensitivity or the vertical size as described above is achieved by adding information relating to the number of effective scanning lines to transmitted video information. It is superimposed on a specific horizontal line in the ranking period as an identification signal. Then, it is preferable to detect the identification signal based on the synchronization pulse of the horizontal line.

FIG. 3 shows an example of such an identification signal. The signals P1 and P2 are inserted in pulses at positions shifted by a phase D from the vertical synchronization signal HD. The pulse width is indicated by E and the pulse interval is indicated by F. In the case of such a signal, in the case of an HD television signal, a vertical synchronizing signal is detected by detecting a frame pulse, thereby recognizing a vertical blanking period and, for example, using a fifth horizontal line on which no effective video signal is carried. The presence / absence of the pulse-shaped identification signal is detected by the identification signal separation circuit unit 10, and a signal of the detection result is supplied to the deflection circuit unit 9. Deflection circuit section 9
The vertical deflection system sets the sensitivity of the vertical deflection system according to this signal so that the vertical deflection angle becomes a predetermined vertical deflection angle by, for example, adjusting the power supply voltage value of the deflection circuit or adjusting the vertical size. Even when the number changes, the image is not deviated or chipped.

The insertion position and shape of the identification signal can be changed to an arbitrary horizontal line within a range that does not affect the image, and the identification signal may be inserted at an appropriate frame period. Further, the embodiment of the present invention can be applied when the number of effective lines is changed even in the case of a video signal of another format regardless of the HD video signal.

[0016]

As described above, the television receiver of the present invention is capable of recognizing the changed information even when the number of effective scanning lines of a video signal of a predetermined television system is changed. Since the signal of the deflection system is controlled by superimposing the signal on the video signal, it is possible to automatically correct the display image on the monitor from being biased or missing.

[Brief description of the drawings]

FIG. 1 is a block diagram showing an outline of a television receiver of the present invention.

FIG. 2 is an explanatory diagram of a deflection angle set by the number of effective scanning lines in the vertical direction.

FIG. 3 is a waveform chart showing an example of an identification signal of the number of effective scanning lines.

FIG. 4 is a diagram illustrating an example of an image when the number of effective scanning lines of an HD television signal changes.

[Explanation of symbols]

1 parabolic antenna and converter, 2 BS tuner, 3 A / D converter, 4 MUSE signal processing unit, 5 audio decoder, 6 synchronization signal separation circuit,
7 video signal processing unit, 8 timing generation circuit,
9 deflection circuit 10 control signal separation circuit

Continued on the front page (51) Int.Cl. ⁶ Identification code FI H04N 5/46 H04N 5/46

Claims (5)

[Claims] 1. A receiving means for receiving a television signal of a predetermined system, a monitor means for displaying a video signal demodulated by the receiving means, and the monitor based on synchronization information contained in the video signal. A television receiver provided with a deflecting means for scanning means, comprising: an identification signal detecting means for detecting an identification signal indicating effective video line information of the video signal, wherein the deflection is performed based on the detection signal of the identification signal detecting means. A television receiver characterized by switching the vertical deflection sensitivity (size) of the means. 2. The television receiver according to claim 1, wherein the identification signal indicating the effective video line information is inserted in a vertical blanking period. 3. The television receiver according to claim 2, wherein said video signal is a high-definition video signal. 4. The method according to claim 1, wherein the number of effective scanning lines of the video signal is inserted into a horizontal line within a vertical blanking period as an identification signal and transmitted. A method of transmitting and receiving a television signal, wherein sensitivity (size) is automatically set according to the number of effective scanning lines. 5. The method according to claim 4, wherein said video signal is a high-definition television signal.