JPH065947B2 - Television signal processing device - Google Patents

Description

Description: BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a television signal processing device, and in particular, a scan line is interpolated by using a motion vector between frames and fields to reproduce a high-definition image. The present invention relates to a television signal processing device.

2. Description of the Related Art In recent years, many methods have been proposed for accurately receiving current television broadcasts and transmitting high-definition signals while maintaining compatibility. Among them, to improve the horizontal resolution, the high frequency component of the luminance signal is stacked on the color signal and transmitted (for example, Japanese Patent Laid-Open No. 60-12883), or multiplexed in the space of three-dimensional frequencies (for example, Kaisho 59-171387
The method and the like are conceivable. Further, as a method for improving the vertical resolution, a method of converting a conventional interlaced scan into a non-interlaced (sequential) scan using a memory (for example, Japanese Patent Laid-Open No. 58-101583) is considered. There is.

Hereinafter, an example of signal processing for improving the vertical resolution will be described with reference to the drawings.

FIG. 4 shows an example of a block diagram of a conventional motion adaptive scan conversion circuit. In the figure, a video signal is input to the input terminal 23, and is input to the 1-line delay circuit 24 and the field delay circuit 27. Field delay circuit 2
The output of 7 is further input to the field delay circuit 28,
The delay amount by the field delay circuits 27 and 28 is just 1.
It becomes a frame. The input video signal and the output of the field delay circuit 28 delayed by one frame from the input video signal are input to the motion detection circuit 31, and the coefficient K (0K1) corresponding to the motion is obtained from the difference between the two signals. With this K, in the stationary portion, the field delay circuit 27 performs scanning line interpolation by the signal of one field before, and in the moving image portion, the 1 line delay circuit 24, the adder 25, and the coefficient unit 26 use the average value of the adjacent scanning lines to scan lines. Interpolation is performed. FIG. 5 schematically shows the operation of the motion adaptive scan conversion circuit. The solid line shows the scanning line, and the broken line shows the interpolating scanning line when the number of scanning lines is doubled.

Problems to be Solved by the Invention However, in the motion adaptive scan conversion circuit as in the above example, since the scanning line interpolation is performed by the average value of the upper and lower adjacent scanning lines in the moving image portion, the resolution in the vertical direction is Not improved. Further, the vertical resolution is improved because the scanning line is interpolated by the signal of one field before when a certain subject is stationary. However, when the subject starts moving, the subject portion is scanned by the average value of the adjacent scanning lines. Since the line interpolation is performed, the vertical resolution is deteriorated as compared with the stationary state, and there is a problem that unnaturalness occurs due to the large difference.

Means for Solving Problems Conventionally, a method of detecting a motion vector as motion information between frames and fields in a television signal or the like and correcting the motion has been considered. Furthermore, a method of dividing a screen into a large number of blocks, detecting motion vectors for each block, and performing motion compensation for each block has been considered (for example, IEICE Image Engineering Research Group Technical Report IE78). -6).

The present invention uses a motion vector as motion information to perform scanning line interpolation using a signal of a previous field or a previous frame even in a moving image portion, thereby improving a vertical resolution of a moving image without deterioration of image quality. Is provided.

Function In the signal processing circuit of the present invention, the scan line interpolation is performed using the signal of the previous field for the static part as in the conventional case, and the motion vector between fields or frames is also detected for the moving image part to detect the signal of the previous field. Since the scanning line interpolation is performed by moving the motion vector according to the motion vector, it is possible to always obtain a high-quality image in which the vertical resolution is improved irrespective of the stationary state and the moving state.

Embodiment One embodiment of the present invention will be described below with reference to the drawings. FIG. 1 is a block diagram showing the configuration of an embodiment according to the present invention.
The video signal is input to the input terminal 1, and is input to the 1-line delay circuit 2, the frame 5 controlled by the motion vector, the motion vector / vector movement area detection circuit 6, and the still area detection circuit 7. Among the moving image parts, those moving in the same manner as the motion vector are controlled by controlling the frame memory 5 by the motion vector, so that only the necessary part, that is, the vector moving region, is extracted from the previous field and used as an interpolation signal. For the static portion, the signal one field before is used as an interpolation signal by the frame memory 5. For the other part, that is, the part of the moving image part that moves differently from the motion vector, the 1-line delay circuit 2, the adder 3, and the coefficient unit 4
The average value of the upper and lower adjacent scanning lines is used as the interpolation signal.

FIG. 2 shows an embodiment of the motion vector and vector movement area detection circuit. The video signal is input to the input terminal 11, and the comparator 13 compares it with the signal delayed by the frame memory 12, finds the case where the error is smallest, and determines the address at that time from the address control 14 of the frame memory. By determining the motion vector, the motion vector is determined. Further, for example, the area in which the pixels in which the motion vector has been determined has the smallest error is stored in the frame memory 16 as a vector movement area. The video signal is divided into several blocks, and a motion vector is obtained in each block. Therefore, as many motion vector detection circuits as the number of divided blocks are required.

FIG. 3 is a diagram showing an example of a scanning line interpolation processing method using a motion vector in a certain block in a video signal. Reference numeral 19 is an area occupied by a moving subject in the previous field, and numerals 20 and 21 are areas occupied by a moving subject in the current field. The area 19 corresponds to the area 20,
The motion vector 23 is obtained from the movement amount. The area 20 is an area in which the motion is the same as that of the motion vector, that is, a vector movement area, so that the area 19 in the previous field is used as an interpolation signal. 19,21 in the current field
Although the area is regarded as a moving image part, it cannot be used for interpolation because it has a different motion from the motion vector and has no correlation with the signal of the same area in the previous field. For such a portion, the average value of upper and lower adjacent scanning lines is used as an interpolation signal. From the above block 19, 20, 21
Since the 22 areas excluding the area 1) are static portions, the signal one field before is used as the interpolation signal.

According to the present invention, in the signal processing device for improving the vertical resolution of the video signal, by adopting the method of the scanning line interpolation by using the motion vector, the method of positively interpolating by the signal of the previous field is adopted. In addition to improving most of the vertical resolution in the video signal, the vertical resolution of a moving subject is always constant regardless of the still or moving state of the subject, so a high quality image without an unnatural image. Can be obtained.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a block diagram of an embodiment of the present invention, FIG. 2 is a block diagram of a motion vector and vector movement area detection circuit,
FIG. 3 is a schematic diagram showing an example of a scanning line interpolation processing method using motion vectors, and FIG. 4 is a block diagram showing a conventional example.
FIG. 5 is a schematic diagram of conventional scanning line interpolation processing. 2, 24 ... Line memory, 27, 28 ... Field memory, 5, 12, 16 ... Frame memory, 3, 2
5, 32 ... Adder, 4 ... Coefficient unit, 29, 30 ... Multiplier, 13 ... Comparator, 9, 33 ... Time axis compressor.

 ─────────────────────────────────────────────────── ─── Continuation of front page (72) Inventor Sadaji Kageyama 1006 Kadoma, Kadoma City, Osaka Prefecture Matsushita Electric Industrial Co., Ltd. Electronic Industry Co., Ltd.

Claims (2)

[Claims] 1. An interlaced video signal as an input, and 1
One field or frame is divided into blocks, and the field or interframe motion vector in each block is detected for each block, and the previous field or previous frame is moved according to the above motion vector to interpolate the scanning line of the current field. A television signal processing device comprising: 2. A means for discriminating between a still portion and a moving image portion in a video signal, a means for detecting a motion vector, and interpolation of each portion of the video signal based on the above information by an average value of vertically adjacent scanning lines. A means for switching between interpolation by a signal of one field or one frame before, and interpolation by a signal obtained by moving the signal of the previous field or previous frame in accordance with the motion vector, is constructed. The television signal processing device according to claim 1.