JPS62260488A - Television signal receiver - Google Patents

Abstract

PURPOSE:To allow a circuit with a simple constitution to remove the deterioration of picture quality due to scan and conversion by controlling the seventh signal processing circuit that selects either one of the outputs of the 1st and 2nd conversion circuits or mixes them at the prescribed ratio at least by the output of the 3rd signal processing circuit. CONSTITUTION:When the field of an interlace scan type, which is supplied to a signal input terminal 802, is odd, an odd scan line selects the output of the 1st conversion circuit 804, while an even scan line selects the output of the 2nd conversion circuit 805. In a next even field, the even scan line selects the output of the 1st conversion circuit 804, while the odd one selects the output of the 2nd conversion circuit 805. In terms of picture elements in the mobile part of a picture, a switch 806 is controlled by a control signal supplied through a conductive line 8081 so that the switch 806 can select uniquely the output of the 1st conversion circuit 804 whatever the scan line and the field are. Accordingly the switch 806 transmits high definition television signals that are sequentially converted into signals of the scan type to a signal output terminal 809.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of the Invention The present invention relates to a television signal receiving device, and more particularly, it is a television signal receiving device that sequentially scans an image signal of Inter 7-7 format, which is subjected to band compression processing using multiple sub-Nyquist sampling. The present invention relates to a device for converting signals into signals.

Conventional technology When transmitting a wideband image signal such as a high-definition television signal, the signal bandwidth is reduced by multiplex sub-Nyquist sampling [Television Society of Japan technical report "Satellite 1-channel transmission system for high-definition television J]
(MUSE) TE B 595-2vOe7㎖4
4) has been proposed. This MUSE method applies an offset to the sampling phase between fields, frames, and lines, and transmits an image signal by performing processing such that the sampling phase goes around in four fields, that is, two frames. Therefore, the receiving device is equipped with a frame memory to store image signals transmitted sequentially over four fields, and combines them to restore a high-definition television image.The scanning method uses the known 2:1 interlace. used. below,
A conventional example of this MUSE type television receiving apparatus will be explained with reference to FIG. 2.

A digitized image signal is supplied to the signal input terminal, and this signal is supplied via a conductor 11 to an interframe interpolation processing circuit comprising a switch 20° and a frame memory 3o. This switch 2o connects the incoming input signal to the frame memory 3.
It multiplexes the signal of the previous frame which is the furthest away from 0, and therefore sends out an image signal interpolated between frames to the conductor 21. On the other hand, the image signal supplied to the signal input terminal 1o is also supplied via the conductor 12 to a moving image filter 30 that performs a predetermined filtering process.
A signal for a moving part in the image is supplied to the mixing circuit 4o via the . The inter-frame interpolated image signals sent to the aforementioned conductor 21 are sent to the mixing circuits 40. through conductors 22 and 23, respectively. The signal is supplied to a motion detection circuit 50. The motion detection circuit 40 has the output of the frame memory 30 supplied to other inputs via a conductor 36, detects a moving part using frame correlation of the image, and sends the motion control circuit to the mixing circuit 40 via a conductor 51. supply the signal.

Therefore, in response to the motion control signal supplied via the conductor 61, the mixing circuit 4o predetermines the signal from the conductor 22 for pixels in the still image portion, and the signal from the conductor 36 for pixels in the moving image portion. The output is mixed or switched at the ratio of . The output of the mixing circuit 40 is supplied via a conducting wire 41 to one input of the field memory 6o and an interpolation filter 70 that performs interpolation processing between fields.
The interpolation filter 7o is configured to perform interfield interpolation processing only on pixels in the still image portion in response to a motion control signal supplied from the motion detection circuit 6 through the conductor 52, and outputs a signal. The restored high-definition television image is sent to the terminal 100.

Problems to be Solved by the Invention In the above-mentioned receiving device, the transmitted television signal is
:1 Because of the interlaced scanning format, it is necessary to independently arrange a scan conversion device to supply signals to a display device having a different scanning mechanism. For example, a high-definition television signal based on the MUSE method of 2:1 interlaced scanning with a field frequency fv (Hz) and a number of scanning lines N (number of lines) has a field frequency fv (Hz) and a number N of scanning lines.
(Book) To convert to a progressive scanning signal, place a field memory for conversion, and place two adjacent fields +, L-rr1 notes t'-'-i-? 77ノ77″2-
fr)=±=large m saw, /7'%ITtI+-1'l7
By compressing the time by ΔV and transmitting it, things such as still images can be converted favorably. However, for moving image parts, image quality deterioration such as double images occurs, so it is better to generate a scanning line interpolation signal from a single field signal and use this. Not only does this require additional motion detection circuitry for detecting moving and static parts of the image, but in this case, it is necessary to process every pixel of the restored high-definition television image. This poses problems such as the need for additional equipment, making the device extremely expensive.

Means for Solving the Problems The receiving device according to the present invention includes a first processing circuit that receives all interlaced scanning television signals subjected to band compression processing using multiple sub-Nyquist sampling, and performs interframe interpolation processing; a second signal processing circuit that performs spatial interpolation processing on the received current field signal; a third signal processing circuit that detects a dynamic portion by using the interframe phase difference of the image signal; and the third signal processing circuit. a fourth signal processing circuit that is controlled by the output of the processing circuit and operates to mix the respective outputs of the first and second signal processing circuits at a predetermined ratio or select one of them; A fifth signal processing circuit performs interfield interpolation processing using the output signal of the fourth signal processing circuit as input, and converts an interlaced scanning television signal sent out from the fifth signal processing circuit into a progressive scanning signal. An additional sixth signal processing circuit is arranged, and the sixth signal processing circuit is configured to be controlled by the third signal processing circuit.

Operation In the receiving device according to the present invention having the above-described configuration, the signal sent out by the sixth signal processing circuit constitutes the sixth signal processing circuit and is used as a signal processing circuit to obtain a sequential scanning type signal compared to the signals of two adjacent fields. It operates to select either one of a single field signal conversion circuit and a second signal conversion circuit that obtains a sequential scanning signal from only a single field signal, or to mix them at a predetermined ratio, and to select or mix them at a predetermined ratio. The blending operation is controlled pixel by pixel by a third signal processing circuit that detects moving parts.

Therefore, the sixth signal processing circuit is characterized in that it sends to the signal output terminal the output signal of the first signal conversion circuit for pixels in the still part of the image, and the output signal of the second signal conversion circuit for pixels in the moving image part. have.

Embodiments Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. Components having the same purpose and operation as those in FIG. 2 showing a conventional example are designated by the same reference numerals and explanations thereof will be omitted.

In FIG. 1, an interlaced scanning signal selected by an interpolation filter 70 that performs interpolation processing between fields for pixels in a still portion is sent to a first signal input terminal 8o1 of a scan conversion circuit 8o. The first. It is shown that the signal is supplied to second conversion circuits 804 and 805, respectively. For example, as shown in FIG. 3, the first conversion circuit 1 supplies delay circuits 8041 and 8042 connected in series for delaying an interlaced scanning signal by one scanning line, and an adding circuit 8o43 supplies a scanning line interpolation signal. A first time compression circuit 8044 compresses the time axis to 1/2, and a delay circuit 8041.

The time axis of the so-called sample scanning line signal from the connection midpoint of 8o42 is compressed to 1/2 by a second time compression circuit 8o46, and the outputs of these two time compression circuits are connected to a switch 8046.
By alternately selecting each scanning line of the progressive scanning signal, the progressive scanning signal is obtained from only the scanning lines of a single field. Second conversion circuit 805
For example, as shown in FIG. 4, the signal supplied via the conductor 803 is delayed by one field in the field memory 8Q51, and the third time compression circuit 8052 delays the signal supplied through the conductor 803 by one field. Similar to the second time compression circuit, the time axis is compressed to 1/2. These first. The switch 806 to which the output of the second conversion circuit is supplied has its signal selection operation controlled by the signal from the aforementioned path 80B with respect to the signal supplied to the second signal input terminal 807. For example, for pixels in a still part of an image, if the sample scan line of the progressive scan signal, that is, the field in the interlaced scan system supplied to the signal input terminal 802 is an odd field, the first pixel in the odd scan line The output of the conversion circuit 804 is selected, and the output of the second conversion circuit 806 is selected for even scan lines. In the next field, that is, an even field, the even scan line selects the output of the first conversion circuit 804, and the odd scan line selects the output of the second conversion circuit 806. On the other hand, for the pixels in the moving part of the image, the switch 806 is controlled by the control signal supplied via the conductor 8081 to the first conversion circuit 8
04 output is selected. Therefore, the switch 806 sends a high-definition television signal converted into a progressive scanning signal to a signal output terminal 809.

In the above-mentioned device, the first . Since the number of pixels in one scanning line of each signal supplied to the second signal input terminal -7-801.807 is in a 2:1 relationship, the third conversion that processes the signal of the second signal input terminal 807 As shown in FIG. 5, the circuit 808 is a one-pixel delay circuit 8101. Addition circuit 8
102. Interpolation filter 810 consisting of switch 81o3
to determine the number of pixels in one scanning line at the first signal input terminal 80.
After processing it so that it is the same as 1, 8081 to 8
Although it is desirable to perform vertical interpolation processing consisting of 086, it is not necessarily limited to this configuration, and various modifications and applications are possible in implementing the present invention. For example, it is within the scope of the present invention to configure the switch 806 of the scan conversion circuit 80 as a mixing circuit and configure the third conversion circuit 8o8 to be suitable for controlling the mixing circuit.

Effects of the Invention As described above, the television signal receiving apparatus according to the present invention restores the interlaced scanning television signal, which has been subjected to band compression processing using multiple sub-Nyquist sampling, in the form of interlaced scanning, and reproduces the restored signal. When converting to a more progressive scanning type signal, the output signal of the motion detection circuit used for restoring the band compression process is used as a control signal without installing a new motion detection circuit, and the pixels in the still part of the image are For pixels in the moving part, sample pixel signals are obtained from signals of a single field.

Since it is configured to obtain interpolated pixel signals, it not only eliminates image quality deterioration caused by scan conversion with a simple device configuration, but also has industrial value such as the fact that the display device can be either an interlaced scan type or a progressive scan type. Extremely large.

[Brief explanation of drawings]

FIG. 1 is a block diagram showing a television signal receiving device according to an embodiment of the present invention, FIG. 2 is a block diagram showing a conventional television signal receiving device, FIG.
4 and 5 are block diagrams showing specific examples related to one embodiment of the present invention. 20...Switch, 30.60...Memory, 36...Video filter, 40...
・Mixing circuit, 60...Motion detection circuit, 70...
...Interpolation filter, 80...Scan conversion circuit, 10.901.807/809°. ...Terminal. Name of agent Patent attorney Satoshi Nakao and 1 other person Figure 3 Figure 4

Claims (1)

[Claims] A receiving device for an interlaced scanning television signal subjected to band compression processing using multiple sub-Nyquist sampling, the receiving device comprising a first signal processing circuit that performs interframe interpolation processing, and an incoming input signal. a second signal processing circuit that performs spatial interpolation processing on the signal of the current field; a third signal processing circuit that detects a moving part by using interframe correlation of the image signal; and an output of the third signal processing circuit. a fourth signal processing circuit that is controlled by the controller and operates to mix the respective outputs of the first and second signal processing circuits at a predetermined ratio or select one of them; It has a fifth signal processing circuit that performs interfield interpolation processing on the output signal, and a sixth signal processing circuit that converts the interlaced scanning television signal sent by the fifth signal processing circuit into a progressive scanning signal. , the sixth signal processing circuit includes a first signal conversion circuit that obtains a progressive scanning signal from signals of a plurality of different fields, and a second signal conversion circuit that obtains a progressive scanning signal from a signal of a single field, A seventh signal processing circuit for selecting one of the outputs of the first and second signal conversion circuits or mixing them at a predetermined ratio is controlled by at least the output of the third signal processing circuit. Features of this television signal receiving device.