JPH0588034B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION Field of the Invention The present invention relates to a television receiver that is compatible with current systems and capable of receiving high quality screens.

BACKGROUND TECHNOLOGY AND PROBLEMS There has been proposed a so-called high-definition television that doubles the number of horizontal scanning lines and doubles the horizontal resolution. However, such high-definition television is not only incompatible with current television systems, but also requires revisions to broadcasting equipment and channel plans as the video frequency quadruples, making it difficult to put it into practical use. Ingredients.

OBJECTS OF THE INVENTION In view of the above-mentioned points, the present invention is intended to be compatible with the current system and to enable reception of high-quality screens.

Summary of the Invention The present invention reduces the number of scanning lines per field for image signals obtained at the same time, receives television signals transmitted over n fields, and transmits the signals over the n fields by reducing the number of scanning lines per field. - A television receiver characterized by increasing the number of scanning lines per field by combining using a delay memory within one field, which is compatible with the current system and provides high quality. screen can be received.

Embodiment First, a transmitting side device will be explained with reference to FIGS. 1 and 2.

In FIG. 1, 1 indicates a television camera. This camera 1 is, for example, a so-called high-definition television camera that has double the number of horizontal scanning lines and double the horizontal resolution, and has a video signal band four times as large as the current one.

A signal from this camera 1 is supplied to a memory circuit 2 having a storage capacity for, for example, one field (four times the current capacity). In addition, the vertical synchronization signal from the synchronization generator 3 and the horizontal synchronization signal with twice the frequency are transmitted to the camera 1.
These synchronization signals are supplied to the timing generator 4, which includes a 4-frequency divider circuit for vertical synchronization signals, etc.
The signal from the generator 4 is supplied to the address control circuit 5. This address signal is then supplied to the memory circuit 2.

Here, from camera 1, select any field F ₁
An image as shown in FIG. 2A is then supplied to the memory circuit 2 and stored. Reading from this memory is performed in relation to the current vertical and horizontal frequencies, and the second
As shown in Figure B, take out the signal marked with (〇) in field _F1 , and transfer it to the following field _F2 (△).
Take out the signal of the marked part, take out the signal of the marked part of field F ₃ , take out the signal of the marked part of field F 3, and put it in field F ₄ .
Take out the signal marked with (□). field here
The screens of F ₁ and F ₃ and F ₂ and F ₄ are horizontally interleaved (dot interleaved). Note that each signal is extracted so that the time axis is expanded twice. Further, the reading of the field F ₁ is started at the beginning of each horizontal period at substantially the same time as the writing, and is taken out so that the time axis is doubled. Further, the signal may be extracted as shown in FIG. 2C.

Therefore, from this memory circuit 2, a signal of the same video signal band as the current one is extracted with the same number of horizontal scanning lines and horizontal resolution as the current one. This signal is transmitted through the existing modulation circuit 6 and transmission circuit 7.
Here, this transmitted signal is line interlaced with odd and even fields,
It is equivalent to the current signal and can be received as is with current television receivers. In other words, this signal is compatible with the current system.

The signals thus transmitted are received using a television receiver as described below.

In FIG. 3, a signal received by a receiving circuit 11 is detected by a detection circuit 12 and supplied to a memory circuit 13. Further, the signal from the detection circuit 12 is supplied to a synchronization separation circuit 14, and the separated synchronization signal is supplied to an address control circuit 15. This address signal is then supplied to the memory circuit 13.

Here, a signal is extracted from the detection circuit 12 as shown in FIG. 4A. When the memory circuit 13 has a storage capacity for one field (currently), the detection circuit 1
The signal from 2 and the signal from 1 field before are combined to form a signal with twice the number of horizontal scanning lines.

This signal passes through the video output circuit 16 to the receiving tube 1.
7. Further, the signal from the synchronization separation circuit 14 is supplied to a deflection circuit 18 to form a deflection signal in which the horizontal frequency is doubled while the vertical frequency remains separated, and the deflection signal is supplied to the picture tube 17.

Therefore, an image with twice the number of horizontal scanning lines is displayed on the picture tube 17, and a high-quality image can be obtained.

Note that when the horizontal frequency is doubled as described above, it is necessary to compress the time axis of the video signal to 1/2. Alternatively, two electron beams may be used to simultaneously project two horizontal scanning lines without increasing the horizontal frequency.

In addition, when the memory circuit 13 has a storage capacity for two fields, the signals of fields F ₁ and F ₂ , F ₃ and F ₄ , F ₅ and F ₆ . . . are transmitted as shown in FIG. 4C. Combine them into pairs and take them out twice each time. This also forms a signal with twice the number of horizontal scanning lines. The rest is the same as in the case of FIG. 4B described above. In this case, field F ₅
The screen distortion that occurs when signals at different points in time are combined does not occur.

Furthermore, if the memory circuit 13 has a storage capacity for three fields, the signals of fields F ₁ to _{F 4} , F ₂ to F ₅ , F ₃ to F ₆ . . . are transmitted as shown in FIG. 4D. When combined, the number of horizontal scanning lines and horizontal resolution is 2.
Double the signal is formed. Therefore, in this case, an extremely high quality image can be obtained. In this case, the writing W and reading R of the 3-field memories [1], [2], and [3] are performed as shown in Figure 5, and the signals read from each memory and the detection output at that time are synthesized. be done.

In this way, it is possible to receive high-quality images that are compatible with current systems.

Note that by providing the memory circuit 13 with a storage capacity for six fields, signals can be synthesized as shown in FIG. 4E, but this method is impractical because the memory capacity becomes too large.

By the way, in the above device, 1 in 4 fields
For example, when applied to the NTSC system, 15 images are formed per second. For this reason, some flickering occurs on the screen when a fast-moving subject is photographed. On the other hand, it is known that when the subject moves quickly, there is no problem even if the screen resolution deteriorates.

Therefore, when the subject is moving slowly on the transmitting side, images are taken every 4 fields as shown in Figure 6A.
When shooting at high speeds, shoot every 2 fields as shown in B. In either case, the signal transmitted at this time is as shown in FIG. 6C. Furthermore, control signals S ₁ and S ₂ indicating whether the photographing was performed at A or B are superimposed on this transmission signal and transmitted. Then, the receiver detects the control signals S ₁ and S ₂ and switches to the image receiving system shown in FIG. 4C and D in response to the control signals to perform image reception.

In this way, a high-quality image can be obtained when the subject is moving slowly, and a flicker-free image can be displayed even when the subject is moving quickly.

Furthermore, if the subject is moving more quickly, it may be possible to photograph each field and directly extract a signal as shown in FIG. 6C. In this case, the receiver uses the control signal _S3 to perform reception equivalent to the current receiver. In this case, the number of scanning lines may be made equal to that described above by displaying the same horizontal scanning line twice.

In other words, as shown in Figure 7, the subject's movement is divided into ``slow,''``fast,'' and ``even faster.''
Photographing is carried out every two fields or every field, and the signals are divided into four fields or two fields, or taken out for each field, and the control signals S ₁ , S ₂ , S ₃ are superimposed and transmitted. Then, in the receiver, when the control signals are S ₁ and S ₂ , 4 fields and 2 fields are combined and projected four times and twice, respectively, and when the control signal is S ₃ , each field is projected.

In this way, it is possible to perform high-quality reception that is compatible with fast movements.

Effects of the Invention According to the present invention, a high-quality screen that is compatible with the current system can be received.

[Brief explanation of the drawing]

1 and 2 are diagrams for explaining the transmitting side device, FIG. 3 is a configuration diagram of an example of the present invention, and FIGS. 4 to 7 are diagrams for explaining the same. 11 is a tuner, 12 is a video detection circuit, 13 is a memory circuit, 14 is a synchronization separation circuit, 15 is an address control circuit, 16 is a video output circuit, 17 is a picture tube, and 18 is a deflection circuit.

Claims (1)

[Claims] 1 Images of slow-moving subjects are captured less frequently and many fields are used, and images of fast-moving subjects are captured more frequently and fewer fields are used. a receiving section for receiving television signals; a storage means provided for combining the television signals made up of the plurality of fields; a control means for increasing the number of fields and increasing the number of times the composite image is read out; and for an image of a fast-moving subject, controlling the number of fields to be composited and reducing the number of times the composite image is read; 1. A television receiver comprising video output means for supplying an image signal synthesized by the means to a picture tube.