JPS62299185A - Forming method for television signal - Google Patents

Abstract

PURPOSE:To reproduce an image having an aspect ratio longer in side than that of a conventional NTSC system television receiver by forming a television signal including the image information in which the aspect ratio is larger than 4:3. CONSTITUTION:An original image signal, in an image separating circuit 2, is separated to a main image signal YM composed of the image of an area M and a sub-image signal YS composed of the image of the area shown by a slanting area S. The main image signal YM is an image signal having the same aspect ratio (4:3) as the conventional NTSC system. The main image signal YM is supplied to a time base multiplex circuit 4, the sub-image signal YS is supplied to an orthogonal converting circuit 3, and in the orthogonal converting circuit 3, the sub-image signal YS is converted onto a space frequency axis. A low order sub-image signal YSL with a high energy is supplied to the time base multiplex circuit 4 and a high order sub-image signal YSM with a comparatively low energy is supplied to a frequency axis multiplex circuit 5. Thus, while the compatibility is kept with a conventional NTSC system, image information having a wide aspect ratio can be transmitted.

Description

[Detailed Description of the Invention] 3. Detailed Description of the Invention Industrial Application Field The present invention is compatible with current television receivers and enables television broadcasting with a horizontally expanded aspect ratio. This invention relates to a method of forming a television signal.

Conventional TechnologyCurrent National Telecommunications (NTSC)
vision sys-Lem Com1ttee
) system began color television broadcasting in 1960, approximately 25 years have passed. Meanwhile, with the demand for high-definition screens and improvements in the performance of television receivers, various new television systems that maintain the same format as the current NTSC system have been proposed. Furthermore, the content of the programs provided is changing from simple studio programs and relay programs to programs with higher image quality and more realistic images, such as cinema-sized movie broadcasts.

Against this background, the Japan Broadcasting Corporation (NHK) proposed a high-definition television system. (For example, Literature Special Feature on High-Definition Television, Journal of the Television Society, Vol. 36,
(Refer to No. 10, 1982) The contents are as follows: Number of scanning lines: 1)
In addition to achieving high definition with 25 trees, interlaced scanning, and a brightness horizontal bandwidth of 20M1-1z, the screen aspect ratio was set to 5:3 from the viewpoint of visual engineering such as a sense of realism. This system has almost been completed in closed systems, and with the start of satellite broadcasting, the MVSE system (Reference, Yu Ninomiya) transmits high-definition television signals in the band of one satellite channel.
In addition, high-definition television satellite 1-channel transmission system (MUS)
E) (Electronic Communication Society Technical Research Report IE84-72.19
1982)), and experiments are underway.

On the other hand, the current NTSC system has 525 scanning lines, interlaced scanning, horizontal brightness bandwidth of 4.2 MIIz, and aspect ratio of 4:3.
It has various specifications.

As an image quality improvement method used in the current NTSC system, there is already a method for frequency multiplexing high-frequency information of an image (for example, Japanese Patent Application Laid-Open No. 60-12883) to improve horizontal resolution.
(Refer to the Publication No.) have been proposed. Further, as a method for improving the resolution in the vertical direction, a method of performing ink-lace scanning-no-inclace scanning conversion has been proposed.

In this way, some practical methods have been proposed for increasing the definition of the current NTSC system, but no practical methods have been proposed regarding the aspect ratio, which greatly affects the sense of scene of an image.

Problems to be Solved by the Invention As mentioned above, in the current NTSC system, the aspect ratio of images is 4:3, and when broadcasting movies etc., both sides are adjusted so that the aspect ratio is 4=3. It can only be transmitted by cutting or compressing it vertically so that the horizontal direction of the effective screen matches the movie.

Therefore, there have been problems such as a loss of realism and a reduction in screen area.

In view of the above-mentioned problems, the present invention provides a method of forming a television signal having a horizontally elongated aspect ratio while maintaining compatibility with the current NTSC television system.

Means for Solving the Problems In order to solve the above problems, the present invention separates the original image signal with an aspect ratio larger than 4:3 into a main image signal and a sub-image signal on the transmitting side, and The image signal is m×n (m
=1.2.3-1n=1.2゜3...) divided into blocks, perform orthogonal transformation for each m x n block, and separate into a low-order sub-image signal and a high-order sub-image signal, The low-order sub-picture signal is multiplexed on the main picture signal in the time domain, and the high-order sub-picture signal is multiplexed on the main picture signal in the frequency domain to form a television signal. The present invention is equipped with a method for forming a television signal that enables reproduction of an original image with an aspect ratio larger than 4=3 by performing the processing described above.

Effect The present invention uses the method described above to reduce the aspect ratio to 4=3.
It enables the formation of television signals containing larger image information, and allows television receivers to use conventional NTS
This makes it possible to reproduce images having a wider aspect ratio than that of a C-scheme television receiver.

Embodiment Hereinafter, a method for forming a television signal according to an embodiment of the present invention will be explained with reference to the drawings.

FIG. 1 is a block diagram showing a method of forming a television signal on the transmission side in a first embodiment of the present invention. 1st
In the figure, 1 is an input terminal for an original image signal with an aspect ratio larger than 4:3, 2 is an image separation circuit, 3 is an orthogonal transformation circuit, 4 is a time-axis multiplexing circuit, 5 is a frequency-axis multiplexing circuit, and 6 is the invention of the present invention. This is an output terminal for a television signal formed by the method described above.

Below, using Figures 2, 3, 4, and 5,
Regarding the method of forming a television signal according to the configuration shown in the figure,
explain. First, FIG. 2 shows an original image whose aspect ratio is larger than 4:3, which is manually input to the input terminal 1 of FIG.
This original image signal is processed in the image separation circuit 2 of FIG.
The signal is separated into a main image signal Y9 consisting of the image in the area indicated by M in FIG. 2 and a sub-image signal consisting of the image in the area indicated by the hatched area S. Note that this main image signal has the same aspect ratio (4:3) as the conventional NTSC system, as shown in Figure 4.
), and has a signal form that allows a conventional NTSC television receiver to reproduce the area M of the original image in FIG. A main image signal Y separated in the image separation circuit 2 of FIG. is supplied to the time axis multiplexing circuit 4, and the sub-image signal Y is supplied to the orthogonal transformation circuit 3.

In the orthogonal transform circuit 3, the sub-image signal is transformed onto the spatial frequency axis. In general, when image signals are transformed onto the frequency axis by orthogonal transformation, energy is concentrated in low-order terms as shown in Figure 3 (al). Therefore, as shown in Figure 3 (bl), the spatial On the frequency axis F (0,
An arc of radius α (0 × α<3) is drawn with O) as the center, and the signal is separated into a low-order sub-image signal YSL inside the arc and a high-order sub-image signal Ys1) outside the arc. This low-order sub-image signal YsL with high energy is supplied to the time-domain multiplexing circuit 4, and the high-order sub-picture signal Y3+1 with relatively low energy is supplied to the frequency-domain multiplexing circuit 5. In the time axis multiplexing circuit 4, during the vertical retrace period VBL or horizontal retrace line HBL of the main image signal (FIG. 4) supplied from the image separation circuit 2, the low-order sub signal supplied from the orthogonal transformation circuit 3 is The image signals are multiplexed and supplied to the frequency axis multiplexing circuit 5. This low-order sub-image signal YsL
As shown in Fig. 5, the frequency spectrum of the main image signal Y'a, which is time-axis multiplexed, becomes NTS when a part of it is enlarged.
Similar to the C method, Y's appears as a line spectrum (in the case of a still image) with 301)z intervals. Frequency axis multiplex circuit 5
In the above-mentioned 301)z frequency gap, as shown in FIG. Since this high-order sub-picture signal has relatively low energy, even if the signal outputted from the output terminal 6 is received by a conventional NTSC television, the interference to the main picture signal will be slight. Furthermore, the time-axis multiplexed low-order sub-image signal with high energy is multiplexed during the retrace period, so it does not appear on the receiver screen.

As described above, according to this embodiment, the aspect ratio is 4:3.
The conventional NTS
It is possible to transmit image information having a wide aspect ratio while maintaining compatibility with the C method.

The following is a block diagram showing a method of forming a television signal on the receiver side, showing a second embodiment of the present invention. In the figure, 10 is an input terminal for a television signal formed by the method of the first embodiment of the present invention, 1) is a frequency axis separation circuit, 12 is a time axis separation circuit, 13 is an orthogonal inverse transform circuit, and 14
1 is an image synthesis circuit, and 15 is an output terminal for the television signal formed in this embodiment.

Hereinafter, a method for forming a television signal using the configuration shown in FIG. 2 will be explained using FIGS. 2, 3, 4, and 5. First, in the first embodiment, a television signal containing sub-picture information that is input manually from an input terminal 1 is passed through an image separation circuit 2 to a low-order sub-picture signal YsL by a comb filter or the like during the retrace period shown in FIG. Multiplexed main image signal Y
's and high-order sub-image signals Y and □, which are supplied to the time axis separation circuit 12 and the orthogonal inverse transform circuit 13, respectively.

The time axis conversion circuit 12 converts the main image signal Y'4 into which the low-order sub-image signals Y and L are multiplexed during the vertical retrace period VBL or horizontal retrace period HBL in FIG.
The signal M and the low-order sub-image signal YsL are separated and supplied to the image synthesis circuit 14 and the orthogonal inverse transform circuit 13, respectively. In the orthogonal inverse transform circuit 13, the inverse transform of the orthogonal transform performed in the orthogonal transform circuit 3 of FIG. 1 is performed, and the low-order sub-image signals Y,
A sub-image signal Y is output from L and the high-order sub-image signal Y, 1), and is supplied to the image synthesis circuit 14. Image synthesis circuit 14
In this case, the main image signal Y. and sub-image signal Y, and an original image signal having an aspect ratio larger than 423 as shown in FIG. 2 is synthesized and outputted from the output terminal 6. By reproducing the original image signal output from the output terminal 6 using a receiving tube,
It is possible to reproduce images with a wider aspect ratio than the current NTSC system.

As described above, by separating the sub-image signal from the television signal formed in the second embodiment by frequency separation, time-axis separation, and orthogonal transformation, and synthesizing and reproducing the main image signal, the current It becomes possible to transmit and reproduce television images with a wider aspect ratio than the NTSC system.

In one embodiment of the present invention, 4X4i! The explanation has been given by treating the ii element as one block and performing two-dimensional orthogonal transformation on it to obtain a 4x4 transformation output, but this orthogonal transformation can also be done in one dimension, and the sub-image signal can be transformed into mxn (
m=1. :"..., n=1.2=-) blocks of any number of pixels.

Effects of the Invention As described above, according to the present invention, when transmitting or servicing movies or programs with a sense of realism, images with an aspect ratio of 5:3, for example, can be played back as they are on the receiver.
It is possible to sufficiently convey the sense of presence and the intention of the program author, and even when received by a current television (NTSC system) receiver, interference is slight, making it extremely effective industrially.

[Brief explanation of drawings]

FIG. 1 is a block diagram showing a method of forming a television signal on the transmission side in an embodiment of the present invention, FIG. 2 is a configuration diagram of the original image input to FIG. 1, and FIG. 3 is a block diagram of the orthogonal transform output. A conceptual diagram, FIG. 4 is a configuration diagram of a main image signal, FIG. 5 is a conceptual diagram of a frequency spectrum of a television signal, and FIG. 6 is a method of forming a television signal on the receiving side in the second embodiment of the present invention. FIG. 2... Image separation circuit, 3... Orthogonal transformation circuit, 4... Time axis multiplex circuit, 5... Frequency axis multiplex circuit, 1)... Frequency axis separation circuit, 12... Time axis separation circuit,
13... Orthogonal inverse transform circuit, 14... Image synthesis circuit. Name of agent: Patent attorney Toshio Nakao (1 person) Figure 1 Figure 2 ---
11 Main image Fig. 3 YSL-・-Yu2ku Hatate 1b Elephant signal Fig. 4 M-Main surface rice Fig. 5 Fig. 6

Claims (3)

[Claims] (1) Separating an original image signal with an aspect ratio larger than 4:3 into a main image signal and a sub-image signal, and separating the sub-image signal into a low-order image signal and a high-order sub-image signal by orthogonal transformation, A method for forming a television signal, characterized in that the low-order sub-picture signal is multiplexed on the main picture signal in a time domain, and the high-order sub-picture signal is multiplexed on the main picture signal in a frequency domain. (2) From a main image signal in which a low-order sub-image signal is time-axis multiplexed and a high-order sub-image signal is frequency-axis multiplexed, the low-order sub-image signal is time-axis separated, and the high-order sub-image signal is frequency-axis multiplexed. The sub-image signal is synthesized from the low-order sub-image signal and the high-order sub-image signal by axis separation and orthogonal inverse transformation, and the aspect ratio of the synthesized sub-image signal and main image signal is 4.
3. The method for forming a television signal according to claim 1, wherein original image signals having a size larger than 3 are synthesized. (3) Divide the sub-image signal into m×n blocks (m=1,
2, 3..., n=1, 2, 3...), orthogonal transformation and inverse transformation are performed for each m×n block, as described in claim (1) or (2). How television signals are formed.