JPS60165883A - Methods for transmission/reception and reception of television signal - Google Patents

Abstract

PURPOSE:To enable conversion into a television system such as standard system based on information at a receiving side by transmitting information as screen frame shape, conversion area location, expansion ratio, compression ratio, etc., which are needed to convert into said signals such as the standard system by a means for superposing the above-mentioned information during a blanking period of a high-accuracy television system signals. CONSTITUTION:A control signal extraction circuit 25 extracts a control signal for controlling a conversion mode, expansion ratio, etc., from the horizontal or vertical blanking period of an input signal, a signal process circuit 27 performs arithmetic from numerical picture elements for correction, and converts them into less picture elements to perform conversion of the number of scan lines in the same way. This method stores pictures of one frame portion of the converted standard television system by a frame memory 30 and writes in by a line memory 26 using an address signal generated from a memory control 31 to read out said pictures.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of Industrial Application The present invention is applicable to high-definition television broadcasting, etc., which transmits and displays images of higher quality than conventional standard television. The present invention relates to a television signal transmission/reception method and a television signal reception method necessary for viewing the contents on a television receiver.

Conventional configuration and its problems Current standard television system, namely NTSC.

High-definition television systems, which have more scanning lines, more frequency bands, etc. than systems such as PALSSECAM, have been proposed and are about to be put into practical use in Japan as well as in Europe and the United States.

If such a television broadcasting system different from the current standard television system is put into practical use, the problem will be that the standard television system receivers that are already in widespread use will not be able to handle high-definition television broadcasting as is. With this in mind, a high-definition television system that is compatible with the standard television system has been proposed. However, of course,
It has the disadvantage that it requires a certain degree of compromise in order to achieve compatibility, and it is difficult to obtain ideal picture quality as a high-definition television system.

Furthermore, ideal high-definition image quality can certainly be obtained by adopting a 2-scanning-line, 9-frequency-band, 9-color signal transmission method, which is completely unrelated to the current standard television system; If you try to watch the content on a television receiver, you will need a considerable amount of hardware for scan conversion and signal format conversion, and the cost of a signal conversion device or a television receiver that can receive both formats will rise significantly. .・
However, with recent advances in semiconductor memories, ICs, etc., and advances in digital signal processing technology, it is believed that the cost of the hardware for signal conversion and the like will be reduced to the extent that it can be put into practical use for consumer use in the near future. Therefore,
As a high-definition television signal, you can easily convert it to a system equivalent to the standard television system on the receiver side without considering compatibility, and you can enjoy a certain amount of content even if it does not reach the level of high-definition. It is expected that this will be possible. In this case, the scanning line 11 is an example of conversion from a high-definition television signal to a standard television signal.
From a high-definition television broadcast signal with 25 lines and a 6:3 aspect ratio to 626 NTSC scan lines and a 4:3 aspect ratio.
The case of conversion to a standard television signal will be explained.

In Fig. 1, a, b, c, and d indicate four typical conversion modes, where 1 indicates a high-definition screen and 2 indicates an area of the high-definition screen to be converted to NTSC. ,3
shows a screen converted to NTSC. 4 is the scanning line of the high-definition image, 6 is the number of pixels in the horizontal direction of the same image, 6 is the number of scanning lines in the area to be converted to NTSC, 7 is the number of pixels in the same area, 8 is the scanning of the image converted to NTSC Line 9 indicates the number of pixels of the same image. Note that these numbers of scanning lines and pixels are shown for the entire area of each signal for ease of understanding, and in reality, processing is often performed using effective scanning lines and pixels excluding the blanking period. In the same figure, a is the same-size conversion mode, and due to the difference in aspect ratio of both signals, N
The TSC converted screen 3 has approximately 20% removed from the left and right sides of the original screen 1.

b shows an example in which the conversion mode is 2 times enlarged, and C shows an example in which the conversion mode is 4 times enlarged. d is a somewhat special full-screen conversion mode in which the converted screen is distorted vertically and displayed so that the edges of the screen are not cut off due to the difference in aspect ratio.
Normally, when a movie is broadcast using the standard television system, characters on the screen are distorted vertically in title scenes, etc. so that they are not cut off. In addition, in a to d, the position of the conversion area 2 is such that a can be freely moved left and right, and b and c can be freely moved up, down, left and right.In addition, the number of scanning lines and pixels for conversion and the conversion The mode is just one example, and it goes without saying that various other examples can be considered.

As explained above with reference to FIG. 1, when viewing high-definition images on a standard television receiver, the viewer must appropriately switch to various modes and move the position depending on the content of the screen. This is because if you were to watch the movie in fixed mode A, if very fine text appeared on a high-definition image, it would naturally become unreadable on the screen of a standard TV Chiron receiver due to insufficient resolution, so This is because the mode must be changed to mode b or mode C.

Therefore, instead of having the pleasure of freely manipulating the screen, the viewer is forced to perform extremely complicated operations when viewing the screen normally. Even if an adapter or conversion device that allows viewing system images becomes easily available, there is a risk that widespread use will not be expected.

OBJECTS OF THE INVENTION The present invention prevents the viewer from being forced to perform complicated operations as described above in an adapter or conversion device that converts a high-definition television signal into a standard television system or other local system, and provides a high-definition image. An object of the present invention is to provide a television signal transmitting/receiving method and a television signal receiving method that can reproduce as much information as possible on a television receiver of a standard television system or the like.

Composition of the invention The present invention reduces scan line blur compared to standard television systems. The image frame shape and position of the conversion area required when converting.

Information such as the enlargement rate and reduction rate is transmitted by means such as superimposing the information on the blanking period of the high-definition television system signal, and the receiving side transmits the high-definition television system signal based on the information to the standard television, / It is characterized by converting it into a television format signal such as a TV format.

Description of examples゛ Examples of the present invention will be described below.

The feature of the present invention is that information on the various conversion modes and conversion area positions as explained in the conventional configuration is transmitted from the high-definition television signal transmitting side such as the program producer. The point is that viewers who convert high-definition television signals and watch them on receivers using different systems can also watch on the optimal screen as intended by program producers. Moreover, if the viewer wishes, he or she can operate the switch as desired, and if such a control signal is not sent, the viewer can operate the screen in the appropriate mode as described above. Unless otherwise specified, the standard image, that is, mode 1 (a) is automatically set. However, this is the case where the aspect ratio of the standard television system is 4:3 and the aspect ratio of the high-definition television system is 6=3 for a horizontally long screen.

If the aspect ratio relationship is reversed, there will be blank spaces at both ends of the converted image, but this is not a particular problem. Note that as the standard mode, in addition to the method shown in FIG. 1a, there may be a method in which the horizontal picture frame is set to exactly match the converted image. In this case, if the aspect ratio of the high-definition television signal is 6:3 and the aspect ratio of the converted image is 4:3, blank spaces will appear at the top and bottom of the converted image. On the other hand, if the aspect ratio relationship is reversed, the top and bottom of the converted image will be slightly removed. In either case, there is no problem in standard mode. Strictly speaking, if margins appear at the top and bottom or left and right ends of the converted image, this corresponds to reduction.

An example of a control signal for controlling image conversion as described above will be explained.

First, four types of image conversion modes a to d in FIG. 1 are assumed. Therefore, 2 bits are required as a control signal. An example of this control signal is shown in FIG. In the same figure, the mode salt a −
d corresponds to a to d in Figure 1.

Next, an example of a control signal indicating the position of the transformation area will be explained with reference to FIG. The figure shows an example of conversion mode C, where 11 is a high-definition screen, 12 is a conversion area, and 13 is the origin of coordinates when the high-definition screen has 1716 pixels horizontally and 1126 pixels vertically. Reference numeral 14 indicates a representative point for indicating the position of the conversion area. Although the positions of 13 and 14 are set as shown in the figure for convenience, they are essentially the same no matter where they are set. In the example of FIG. 3, the coordinates of the 14th point are 87 o horizontally and 120 o vertically. In this way, any location can be converted by transmitting the horizontal and vertical coordinate positions as control signals.

Note that there are limits to the values that the above position coordinates can take depending on the type of mode, and in particular, the vertical gaps in mode a and the vertical and horizontal gaps in mode G are essentially blanking periods, so they cannot be moved and are fixed. value. Also, if you select the upper left position as the representative point of the conversion area as in the case of Figure 3, 14, and take the coordinate value of the lower right corner of the high-definition image, a blanking period will appear on the converted screen, so this also applies. I can't take it. Therefore, the coordinate values are: Horizontal: 10 bits (=210=1o24# (1716 pixels - 682 pixels)) Vertical: 10 bits (=2 - 1024〉 (1126 lines - 626 lines)) A total of 20 bits of data .

The total amount of data required for image conversion is 22 bits including the 2 bits for the mode, and this data only needs to be transmitted once per screen, that is, once per frame. As an example of transmission, a means for transmitting the information together with various other digital information such as a PCM audio signal during the vertical blanking period can be considered. Alternatively, if there is sufficient horizontal blanking period, it may also be provided as a digital signal. Furthermore, even if the video signal cannot be transmitted in the baseband state, it may be sent on a separate carrier wave like audio in a standard broadcasting system, or it may be sent using a completely different transmission means.

Although four examples of a=d have been described as image conversion modes, except for d, which is a special screen, the rest are only different in magnification. Therefore, if this enlargement is performed continuously, a more effective conversion screen can be obtained. For example, if a 32-step change i is desired, 6 bits are required for the control signal, and the total number of bits including position information and special conversion mode is about 26 bits. In order to enlarge an image at various rates or continuously, calculations and interpolation are performed between multiple pixels and scanning lines depending on the enlargement rate, and pixels with fewer pixels than the original number are used. This technology is already used in digital video effectors used in broadcasting stations and is well known.

Next, an example of a signal conversion device for receiving the high-definition television signal and converting the screen will be described with reference to a block diagram shown in FIG. 4. 21 is a high-definition television signal input terminal, 22 is an A/D converter, 23 is a synchronization signal separation circuit, 24 is a clock generator synchronized with the synchronization signal,
Reference numeral 25 denotes a control signal extraction circuit for controlling the conversion mode, enlargement rate, etc. In this embodiment, the control signal extraction circuit is inserted into the horizontal or vertical blanking period of the input signal.

Reference numeral 26 is a line memory for expanding the time axis of the signal, and depending on the scan conversion configuration, several H (H indicates a horizontal scanning period) are required.

27 is a signal processing circuit that performs signal processing for image conversion, and is a part that performs calculations from several pixels, performs interpolation, etc., and converts them to fewer pixels, and converts the number of scanning lines in the same way. . This conversion process is controlled by switching and using either the control signal extracted by the control signal extraction circuit 25 or the control signal generated from the manual operating device 28 using the switch 29. Note that even if the switch 29 is connected to the control signal extraction circuit 25 side, if the control signal is not sent at the same time as the high-definition television signal, the image is automatically set to the standard image of the conversion mode a. It looks like it will be done. In this case, it is appropriate that the conversion area be located at the center of the high-definition television signal.

Reference numeral 30 denotes a memory circuit for storing one frame worth of image of the converted standard television system. Along with this, the line memory 26 is also written and read by an address signal generated by the memory control 31. 31
is a D/A converter, and 32 is a signal output terminal that is supplied to the video input terminal of a standard television receiver, etc. In reality, it is an encoder, etc. that converts it into a composite signal according to the input signal specifications of the display side. may be necessary. It goes without saying that the circuit shown in FIG. 4 needs to have an optimal configuration in accordance with the specifications of the input high-definition television signal.

The image conversion device illustrated in FIG. 4 may be configured either as a stand-alone adapter or incorporated into a standard television signal receiver. Next, another application example of the present invention will be explained. If high-definition television systems become widespread in the future, a high-definition receiver with a small screen of about 10 to 20 inches for personal use will naturally become necessary. In this case, if the normal screen that is always sent is displayed as it is, the small screen will make it difficult for the viewer to make out small details even if the image is high resolution if viewed from a distance. You have to get close and look into the screen. Therefore, it would be very effective if the receiver had a function to enlarge the image as necessary. In this case as well, it would be very complicated if the viewer had to manually operate the screen each time, so the image conversion control signal included in the high-definition television signal is used to automatically enlarge the image. It's good to be able to switch between images. In this case, the aspect ratio and number of scanning lines of the converted signal are the same as the original signal, but the basic configuration can be realized in the same manner as in FIG.

However, the conversion mode is only an enlarged image, and a conversion screen in which the image shown in FIG. 1d changes to a vertically long image does not occur in principle. Therefore, when the conversion control signal indicates an unnecessary mode, it is better to automatically switch to the normal image mode.

In the above explanation, we have dealt with the case where the high-definition television signal is not compatible with the standard television signal, but even if the signal takes compatibility into consideration, for example, a high-definition television signal with around 1050 lines in the blue, Of course, it can be achieved in the same way.

Furthermore, it goes without saying that the present invention is not particularly limited to high-definition television systems, but can also be applied to standard television systems.

Effects of the Invention According to the high-definition television signal transmission system according to the present invention, general viewers who already have a standard television signal receiver can use the same software to the maximum extent intended by the program producer or other transmitter. Even in the early stages of the spread of high-definition television broadcasting, there will be a large number of viewers of the same software, which will bring social benefits and at the same time promote the spread of new broadcasting. Furthermore, by using a receiving device such as a television receiver that includes the image signal converting device according to the present invention, the viewer can view the most effective converted image without any trouble, and even if the control signal is not sent. Even in the case of an upcoming program, the standard conversion mode is automatically set, so there is no risk of unnecessary confusion. Furthermore, when compact high-definition color television receivers for personal use become widespread in the future, the system will automatically switch to the size conversion mode even in situations where it is difficult to produce the impact on a small screen, allowing you to enjoy high-definition images to the fullest. It is possible. In addition, even if you perform the same action on a large high-definition display, not only on a watercolor screen, if a large number of viewers are watching,
This provides very large effects such as a more dynamic screen and the ability to view two different screens on the same high-definition television receiver.

[Brief explanation of drawings]

FIG. 1 is a diagram showing an example of image conversion, FIG. 2 is a diagram showing an example of a control signal for the image conversion mode according to the present invention, and FIG.
The figure is a diagram illustrating an example of a control signal for the position of a conversion area in image conversion according to the present invention, and FIG. FIG. 2 is a block diagram of the device. 21...High-definition television signal input terminal,
26... Control signal extraction circuit, 27...
Image signal conversion processing circuit, 28...Manual operation device, 29.Manual/automatic changeover switch, 32...
...Conversion signal output terminal. 1st agony 5 v 2nd a! 5

Claims (1)

[Scope of Claims] (1) A high-definition television system signal that has a greater number of scanning lines, frequency bandwidth, number of pixels, etc. than the standard television system is converted into a television system signal of the standard television system, etc. The information necessary for conversion, such as the shape of the picture frame, the position of the conversion area, the enlargement rate, the reduction rate, etc., is transmitted by means such as superimposing it on the blanking period of the high-definition television signal, and the receiving side A television signal transmission/reception method characterized by converting a high-definition television system signal into another television system signal such as a standard television system based on the information. The shape of the image frame required when converting a high-definition television signal with a large number of frames, etc., into a standard television signal, etc. The position, enlargement rate, and reduction of the conversion area A television characterized in that it receives a high-definition television system signal having information such as a rate, etc., and converts the high-definition television system signal into a television system signal such as a standard television system based on the information. Signal reception method. (3) Receive a high-definition television signal, convert it to an image of another television system based on the information and display it, and if the information is not transmitted, When a vertical image of a high-definition television signal is displayed to fill the image frame, the left and right sides in the horizontal direction are truncated or a margin is created so that the aspect ratio of the displayed image is displayed without distortion. A method for receiving a television digital signal according to claim 2 of claim □. (4) Receiving a high-definition television signal, converting it into an image of another format based on the information and displaying the image, and if the information is not transmitted. If the horizontal image of the high-definition television signal is displayed to fill the image frame, the top and bottom of the vertical direction should be truncated or a margin should be created so that the aspect ratio of the displayed image is displayed without distortion. The television signal receiving method 0 according to claim 2, characterized in that the television signal is displayed as follows.