JPH084341B2 - Television signal receiver - Google Patents

Description

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a television signal receiving apparatus, and more particularly to a television signal that has been band-compressed by multiple sub-Nyquist sampling as an input. The present invention relates to the configuration of a receiving device having a picture-in-picture function.

2. Description of the Related Art A television receiver having a so-called picture-in-picture function that simultaneously displays images of multiple channels on one screen is
For example, those described in JP-A-49-2419 are known, and a receiver having this function has already been put into practical use.

In this type of current receiver, the luminance signal and chromaticity signal necessary for reproducing a color image are processed into baseband signals, respectively, and then subjected to time compression processing on the sub-channel side and then inserted into the main-channel side. The configuration is often used. For example, as shown in FIG. 2, the NTSC first video signal supplied to the first signal input terminal 1 on the main channel side is processed by the first luminance processing circuit 11 and the first color demodulation circuit 12, and these processing circuits are Switch SW1 for luminance signal and two color difference signals respectively
~ Supply to one input terminal of SW3. The NTSC second video signal from the second signal input terminal 2 on the sub-channel side is processed by the second luminance processing circuit 21 and the second color demodulation circuit 22, and the time compression circuits 23 and 24 are supplied via the lead wire 25. The luminance signal and the two color difference signals on the sub-channel side, which are compressed on the time axis, are supplied to the other input terminals of the switches SW1 to SW3 in synchronization with the phase of the synchronization processing circuit 13 on the main channel side.
The signal selection circuit 15 consisting of SW3 is switched by the control signal from the synchronization processing circuit 13 via the conductor 14 so as to combine the main channel side and the sub channel side in the same screen, and the signal is passed through the matrix circuit 16. R, G, B at output terminals 17, 18, 19
The three primary color signals are transmitted.

On the other hand, in the high-definition television system, the band compression is performed by the multiple sub-Nyquist sampling when transmitting the wideband image signal [Technical report material of the Institute of Television Engineers of Japan, "High-definition television satellite 1-channel transmission system" (MUSE) TEBS95- 2VOl7 No.44] has been proposed.

The MUSE system offsets the sampling phase between fields, frames, and lines, and performs processing such that the sampling phase makes one cycle in four fields, that is, two frames, and transmits an image signal. Therefore, the receiving device is equipped with a frame memory or the like to store the image signals sequentially transmitted over four fields, and these are combined to restore the still image portion, and the motion image portion is spatially interpolated within a single field. This is to be restored, and an example of the MUSE type receiver will be described below with reference to FIG.

A digitized image signal is supplied to the signal input terminal 300, and this signal is supplied to the inter-frame interpolation processing circuit including the switch 302 and the frame memory 303 via the conductor 301. This switch 302 multiplexes the incoming input signal and the signal one frame before fed back from the frame memory 303,
Therefore, the image signal interpolated between the frames on the conductor 304 is selected. On the other hand, the image signal supplied to the signal input terminal 300 is also supplied to the spatial interpolation processing circuit 306 that performs a predetermined filtering process via the lead wire 305, and the spatial interpolation processing circuit 306 receives the mixing circuit via the lead wire 307. The signal for moving parts in the image is supplied to 308. The inter-frame interpolated image signals sent to the above-mentioned conducting wire 304 are supplied to the mixing circuit 308 and the motion detecting circuit 311 via conducting wires 309 and 310, respectively. This motion detection circuit 311 is supplied with the output of the frame memory 303 to the other input through a conductor 312, detects a moving portion by using the frame correlation of the image, and mixes the circuit 311 through a conductor 313.
Supply motion control signal to 08.

Accordingly, the mixing circuit 308 is responsive to the motion control signal provided on line 313 to provide the signal on line 309 for pixels in the still image portion and the signal on line 307 for pixels in the moving image portion. Mix or switch at a predetermined ratio and output. The output of the mixing circuit 308 is supplied via a conductor 316 to one input of a field memory 314 and an interpolation filter 315 that performs interpolation processing between fields.
This interpolation filter is connected to the conductor 317 from the motion detection circuit 311 described above.
The inter-field interpolation processing is performed only on the pixels of the still image portion by the motion control signal supplied via the, and the restored high-definition television image is transmitted to the signal output terminal 316.

DISCLOSURE OF THE INVENTION Problems to be Solved by the Invention The MUSE type receiver described above is used to restore the original high definition television type image signal from the band-compressed incoming input signal. Therefore, when performing picture-in-picture with this receiving device, the receiving devices having the configuration shown in FIG. 3 are arranged in parallel, and after restoring the band-compressed high-definition television signals of the main and sub-channels respectively, It is conceivable to synthesize by a known method as shown in FIG. However, in such a configuration, the scale of the receiving device is doubled or more because of the picture-in-picture, and there is a large problem for equiaxing.

In the receiving device according to the present invention, a still image signal filter circuit, which generates an image signal for a still portion by using signals of a plurality of fields from a first input television signal, and a plurality of horizontal and vertical directions of a single field. And adaptively selecting or mixing the moving image filter circuit, which generates an image signal for a moving portion using the pixel signals of the above, and the image signals for the still portion and the moving portion, according to the movement of the image. And a motion adaptive processing circuit for obtaining the first image signal for the main screen, and a filtering process using a plurality of pixel signals in the horizontal and vertical directions of a single field from the second input television signal and time-axis compression. A sub-screen signal processing circuit that generates and sends out a sub-screen second image signal by performing processing, and a signal for time-division multiplexing these first and second image signals. And selection circuits are arranged.

The still picture trust filter circuit described above uses the signals of a plurality of fields obtained by storing or delaying the first input television signal to perform the inter-frame or inter-field processing alone or in combination, so The image signal for the moving image is restored, and the moving image filter circuit restores the image signal for the moving part by performing the two-dimensional low-pass filter processing in the horizontal and vertical directions using the pixel signals in the single field, and the motion adaptation is performed. The processing circuit detects the motion of the image by using the inter-frame correlation, and adaptively selects the output of the filter circuit for the still image signal and the output of the filter circuit for the moving image with respect to the non-moving part and the moving part, respectively. The signal processing circuit for the sub-screen transmits the first image signal for the horizontal direction, Filtering is performed using a plurality of pixel signals in the vertical direction, and horizontal and vertical time-axis compression processing is performed to send out as a second image signal for the sub-screen, which is output by the signal selection circuit to the first, The second image signal is time-division-multiplexed and sent as an image signal in which these are combined.

Embodiments Embodiments of the present invention will be described below in detail with reference to the drawings. Components having the same functions and operations as those of the conventional device shown in FIG. 3 are designated by the same reference numerals and detailed description thereof will be omitted. . FIG. 1 is a block diagram of an embodiment of the present invention. In the drawing, a first input signal supplied from a first signal input terminal 300 is supplied to a switch 302, a frame memory 303, a first
The first signal processing circuit 30 including the spatial interpolation processing circuit 306, the motion detection circuit 311, and the mixing circuit 308 constituting the first signal selection circuit of the present invention sends the first image signal in the field offset sub-sampling state to the lead wire 316. To do. The second input signal supplied from the second signal input terminal 400 is the second
Two-dimensional interpolation processing is performed by the spatial interpolation processing circuit 401, and the image signal in the field offset sub-sampling state is sent to the conductor 402. The time compression circuit 403 is controlled by the second control circuit 405 that operates in response to the synchronization information of the second input signal from the conductor 404, and the image signal supplied from the second spatial interpolation processing circuit 401 via the conductor 402. In a memory, and the image signal is read out on the read-out conductor 408 in a time-compressed form by the read-out control signal from the first control circuit 407 which operates in response to the synchronization information of the first input signal supplied via the conductor 406. The second image signal is transmitted. The first signal processing circuit 30 has a conductor 31
The first image signal and the second signal processing circuit to be sent to
The signal processing speed of the second image signal is the same as that of the second image signal sent to the second image signal. Therefore, the time compression circuit 403 controls either the second control circuit for controlling writing to the memory or the first control circuit for controlling reading, Alternatively, the thinning processing of predetermined image information is performed by both. For example, the second sending to the lead wire 408
When the image signal is time-compressed horizontally and vertically to 1/4 respectively, at the time of writing or reading, it is processed in a 4: 1 relationship with respect to 4 pixels and 4 scanning lines, or writing and reading are performed respectively 2: In the present invention, the second spatial interpolation processing circuit 401 has a narrow band characteristic that can be realized by processing both horizontally and vertically in the relationship of 1 and low-pass filtering processing for preventing the occurrence of aliasing distortion due to time compression processing. It is also possible to share by doing. The second signal selection circuit 409, to which the first and second image signals are supplied via conductors 316 and 408, is the first control circuit 407, which is supplied via conductor 410.
However, the present invention is not limited to this, and for example, a mixing circuit can be used. In the field offset sub-sampling image signal processing circuit including the field memory 314 and the interpolation filter 411, the conductor 317 is used in the portion where the second signal selection circuit 409 selects the output signal of the first signal processing circuit 30 from the conductor 316. A second signal processing circuit in which the inter-field interpolation processing operation of the motion image portion is prohibited by the control signal from the motion detection circuit 311 supplied via the second signal selection circuit 409 and the second signal selection circuit 409 is supplied via the lead wire 408. In the portion where the second image signal from 40 is selected, the inter-field interpolation processing operation is prohibited by the control signal from the lead wire 410, and the first input signal is applied to the signal output terminal 412 as the main channel and the second input signal is applied. The sub-channel is used as the sub-channel to output the combined image signal. In the description of the embodiment,
The second signal selection circuit 409 is arranged between the field offset sub-sampling image signal processing circuit including the field memory 314 and the interpolation filter 411 and the mixing circuit 308. However, the present invention is not limited to such a configuration. However, it is also possible to apply to television systems other than the MUSE system.

EFFECTS OF THE INVENTION The present invention, when receiving a plurality of band-compressed television signals such as the MUSE system to obtain a multi-screen display signal as described above, performs a filtering process and a reducing process in a single field on the sub-screen side. Since it is combined with the main screen side after performing, it has great industrial value such that the device can be greatly simplified.

[Brief description of drawings]

FIG. 1 is a block diagram of a television signal receiving apparatus in an embodiment of the present invention, and FIGS. 2 and 3 are block diagrams of a television signal receiving apparatus in a conventional example. 300,400 …… Signal input terminal, 30 …… First signal processing circuit, 4
0 ... second signal processing circuit, 302 ... switch, 303 ... frame memory, 306 ... first spatial interpolation processing circuit, 311 ...
Motion detection circuit, 308 ... First signal selection circuit, 401 ... Second
Spatial interpolation processing circuit, 403 ... Time compression circuit, 405,407 ...
Control circuit, 409 ... Second signal selection circuit, 412 ... Signal output terminal.

Claims (1)

[Claims] 1. A receiving device for generating a picture-in-picture or picture-out-picture image from a plurality of television signals, the image signal for a still portion using a signal of a plurality of fields from a first input television signal. And a moving picture filter circuit for generating a moving part image signal by using a plurality of pixel signals in the horizontal and vertical directions of a single field. And a motion adaptive processing circuit for obtaining the first image signal for the main screen by adaptively selecting or mixing the image signal for the moving part and the image signal for the moving part, and a single signal from the second input television signal. A sub-screen is created by performing a filtering process using a plurality of pixel signals in the horizontal and vertical directions of one field and performing a time axis compression process And a signal selection circuit for time-division-multiplexing the first and second image signals, and a sub-screen signal processing circuit for generating and sending the second image signal. Signal receiving device.