JP3201079B2 - Motion compensated prediction method, coding method and apparatus for interlaced video signal - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

[0001] 1. Field of the Invention [0002] The present invention relates to a motion compensation prediction method, an encoding method and an apparatus for an interlaced video signal.

[0002]

2. Description of the Related Art Conventionally, moving image communication such as a video conference and CD
In a high-efficiency video coding method for storing a video in a ROM or the like, each screen is divided into, for example, a block of 16 pixels × 16 lines on a frame or field screen, and intra-frame coding is performed. Alternatively, high-efficiency coding is performed using inter-plane coding for coding a difference between a reference screen and a current screen by motion compensation.

FIG. 1 shows a configuration of a general encoding apparatus. Here, reference numeral 71 denotes a subtracter, which obtains a difference between the input screen X1 and the prediction screen X2 to generate a prediction error screen X3. 7
2 is an encoder such as a discrete cosine transform (DCT) or a vector quantizer; 73 is a quantizer; 74 is an inverse quantizer;
Is a decoder such as an inverse discrete cosine transform (IDCT) or an inverse vector quantizer. 76 is an adder and a decoder 75
Then, the prediction error screen X5 and the prediction screen X2 restored by the above are added to generate a local decoding screen X6. The local decoding screen X6 is used as a reference screen. Note that, instead of the local decoding screen X6, an uncoded original screen, that is, a screen before and after the input screen X1 can be used as the reference screen.

A local decoding screen X6 is stored in the frame memory 77.
And an input screen X1. The motion detection unit 78 performs motion detection in block units. The corresponding input block data 10 and the reference block data 11 of the area to be searched for motion are input from the frame memory 77 to the motion detection unit 78. After the motion detection, the motion vector ZV and the selection flag ZM are output. The motion compensator 79 creates and outputs a prediction screen X2 from the reference block data 11 using the motion vector ZV and the selection flag ZM obtained by the motion detection unit 78.

The output of the quantizer 73 is a variable length encoder 80
, And multiplexed by the multiplexer 81 together with the motion vector ZV and the selection flag ZM obtained by the motion detection unit 78, and output as an encoded output.

FIG. 2 shows an example of the configuration of a conventional motion detecting section 78. As shown in FIG. The frame motion detector 84 detects the motion of the frame block and outputs a prediction error signal ER and a motion vector VR. On the other hand, the field motion detector 85 detects the motion of the field block and outputs a prediction error signal EF and a motion vector VF. These prediction error signals ER and EF are compared by a comparator 87. Comparator 8
7 outputs to the selector 86 a selection flag ZM for selecting the smaller of the prediction error signals ER and EF. Selector 86
Operates in response to this, selects the motion detector with the smaller prediction error signal, and outputs the motion vector ZV from the selected motion detector. As described above, conventionally, a prediction error signal is obtained from the frame motion detector and the field motion detector, and motion compensation is performed using the motion vector of the motion detector with the smaller prediction error signal to improve coding efficiency. ing.

[0007]

SUMMARY OF THE INVENTION The above-described motion detection unit 7
In the coding apparatus using No. 8, motion detection is performed on a frame screen and a field screen, and a motion detector with a smaller prediction error is selected to perform motion compensation. This conventional encoding device has the following problems. (1) When the image moves at an accelerated speed, the screen to be referred to differs between the even-numbered line and the odd-numbered line. For this reason, when the frame motion detector 84 is selected, the prediction error at the time of motion compensation increases, and the coding efficiency decreases. (2) When the screen moves at a constant speed, the amount of movement in each field is almost the same. For this reason, when the field motion detector 85 is selected, the information on the motion vector amount increases twice as compared with the motion compensation on the frame screen, and as a result, the coding efficiency decreases.

SUMMARY OF THE INVENTION Accordingly, an object of the present invention is to solve the above-mentioned problems of the conventional system, and to provide a motion compensation prediction method, a coding method, and a method for interlaced video signals which can improve coding efficiency and image quality. It is to provide a device.

[0009]

According to the present invention, there is provided a motion compensation prediction method for a moving image signal for a continuously input image signal, wherein a specific reference field is set, and a specific reference field and an input Determining a first prediction signal obtained by predicting an input field from a specific reference field using a first motion vector between the specific reference field and a temporal distance between the specific reference field and the input field; Calculating a second prediction signal that predicts the input field from another reference field by converting the magnitude of the first motion vector according to the ratio of the temporal distance between the field and the input field; A method of motion-compensated prediction of an interlaced moving image signal that combines a first prediction signal and a second prediction signal to obtain a third prediction signal of an input field is provided.

For example, an input field having one parity which is an even parity is predicted by synthesizing two reference fields each having one parity and the other parity which is an odd parity, for example. At this time, prediction from a reference field having one parity to an input field having the same one parity is performed using the first motion vector, and prediction from a reference field having the other parity to an input field having one parity is performed. The prediction is
A second motion vector obtained by converting the size of the first motion vector by the distance between fields is used. For this reason, the motion vector to be coded is only the first vector, the amount of information necessary for coding can be reduced, and coding efficiency can be greatly improved.

Further, according to the present invention, an input having one parity is converted from a reference field having one parity by using a first motion vector for predicting an input field having one parity from a reference field having one parity. A first prediction signal obtained by predicting a field is obtained, and a temporal distance between a reference field having one parity and an input field having one parity and an input having a reference field having the other parity and one parity are obtained. By converting the size of the first motion vector in accordance with the ratio of the first motion vector to the temporal distance between the first field and the second field, the second field predicting the input field having one parity from the reference field having the other parity Find the prediction signal, the first
And the second prediction signal are combined to obtain a third prediction signal of the input field having one parity, and the temporal distance between the reference field having one parity and the input field having one parity is calculated. By converting the magnitude of the first motion vector according to the ratio of the temporal distance between the reference field having one parity and the input field having the other parity, A fourth prediction signal which predicts the input field having the other parity is obtained, and a fifth prediction signal which predicts the input field having the other parity from the reference field having the other parity is obtained by using the first motion vector. And interpolating the fourth and fifth prediction signals to obtain a sixth prediction signal of the input field having the other parity. Motion compensated prediction method of moving image signal is provided.

Preferably, an input field having one parity is predicted using a third prediction signal, and an input field having the other parity is predicted using a sixth prediction signal.

In the case of encoding, it is preferable to encode a prediction error screen which is a difference between a prediction signal of an input field obtained by a motion compensation prediction method of an interlaced video signal and an input field.

According to the present invention, furthermore, one parity is provided from a reference field having one parity by using a first motion vector for predicting an input field having one parity from a reference field having one parity. A first prediction signal obtained by predicting an input field is obtained, and a temporal distance between a reference field having one parity and an input field having one parity and a reference field having one parity and one parity are provided. First depending on the ratio to the temporal distance to the input field
By calculating the magnitude of the motion vector, a second prediction signal that predicts an input field having one parity from a reference field having the other parity is obtained, and the first and second prediction signals are combined. A third prediction signal of the input field having one parity is obtained, and the temporal distance between the reference field having one parity and the input field having one parity is determined by the reference field having one parity and the other. The input field having one parity is predicted from the reference field having one parity by converting the size of the first motion vector according to the ratio of the temporal distance to the input field having parity. A fourth prediction signal is obtained, and the other parity is obtained from the reference field having the other parity by using the first motion vector. Motion-compensated prediction means for obtaining a fifth predicted signal predicting one input field, combining the fourth and fifth predicted signals to obtain a sixth predicted signal of the input field having the other parity, First
And an encoding means for encoding the motion vector of the interlaced video signal.

The motion compensation prediction means is configured to predict an input field having one parity by using a third prediction signal and to predict an input field having the other parity by using a sixth prediction signal. Is preferred.

[0016]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, a first embodiment of the present invention will be described in detail with reference to the block diagram of FIG. The motion detector shown in FIG. 3 is a motion detector 78 of the encoder shown in FIG.
It is used as

FIG. 3 shows the configuration of the first embodiment of the present invention, in which 10 is input block data, 11 is reference block data, and these are both interlaced screens. The block data 10 and 11 are subjected to motion detection by the same parity field motion detector 12,
The motion vector V1 and the prediction error E1 of the block are output. In addition, motion detection is also performed by the near field motion detector 13, and a motion vector V2 and a prediction error E2 are output. Further, the motion detection is also performed by the inter-field interpolation motion detector 14, and the motion vector V3 and the prediction error E3 are calculated.
Is output.

The same parity field motion detector 12,
The prediction errors E1, E2, and E output from the near-field motion detector 13 and the inter-field interpolation motion detector 14.
3 is compared by the comparator 15. The comparator 15 selects the smallest one of the prediction errors E1, E2 and E3,
A selection flag ZM, which is a signal indicating which prediction error has been selected, is output. The selector 16 selects a motion vector according to the selection flag ZM, and outputs a motion vector from the motion detector that outputs the smallest prediction error as a motion vector ZV.

After the selector 16 selects the motion vector ZV based on the selection flag ZM, the motion compensator 79 shown in FIG. 1 performs motion compensation using the reference block corresponding to the motion vector as a prediction signal. Do. At this time, the motion vector is used as it is for the luminance signal.
On the other hand, as for the color signal, as will be apparent from the description below, since the block size is half of the luminance in the horizontal direction, the motion vector in the horizontal direction is halved and used.
A prediction signal is created from the luminance signal and the chromaticity signal.

Incidentally, a supplementary outline of the processing on the decoder side (not shown) for receiving and decoding the encoded output output from the multiplexer 81 shown in FIG. 1 is as follows.
Based on the type of motion detection and the amount of motion vector sent from the encoder, a corresponding reference block is searched for, motion compensation is performed, and a prediction signal is created.

Hereinafter, a specific example of the configuration of the main part of the present embodiment will be described in detail.

First, the configuration of block data of the input screen will be described in detail with reference to FIG. Regarding the size of the input block, the luminance signal is 16 pixels × 16 lines, and the two color difference signals are each 8 pixels × 16 lines, and these are collectively called a macroblock. A series of encoding processes is performed for each macroblock.

As shown in FIG. 4, the block is composed of data of an odd field present on an odd line (偶) and data of an even field present on an even line (□). The frame block is
The field block is composed of data in which odd lines and even lines alternately appear, and the field block is composed of data in which only odd line data is collected or data in which only even line data is collected.

For a reference block used for motion detection, only a luminance signal is used. The size of the block changes according to the search range. For example, when the search range is ± 7 pixels in the main and sub-scanning directions, the size is 30 pixels × 30 lines. The size of the prediction error data obtained after the motion compensation has the same configuration as the input block in FIG. 4 for both the luminance signal and the color difference signal.

FIG. 5A shows the block data of the input screen and the block data of the reference screen in the vertical direction and the time axis direction. The data (○) of the odd field f1 exists on the odd line and the even field f1
The data (□) of 2 exists on the even-numbered line.

Next, a specific example of the same parity field motion detector 12 will be described with reference to FIG. The same parity field means that it is between odd fields or between even fields. The input block data 10 and reference block data 11 are temporarily stored in the input block memory 20 and the reference block memory 21, respectively. The first and second field prediction error calculation circuits extract the respective field data of the area for performing motion detection from the input block memory 20 and the respective field data of the search area from the reference block memory 21 according to the address from the address generation circuit 26. At 23 and 24, an error is calculated.

In this case, with respect to an input block signal of 16 pixels × 16 lines, as shown in FIG. 7A, the odd fields f1 and the even fields f2 of the input screen use the same vectors MV1 and MV2, respectively. A prediction error signal is obtained between input data of a field and reference data of an odd field, and a prediction error signal between input data of an even field and reference data of an even field. This prediction error signal can be obtained from the cumulative sum of the absolute difference values or the cumulative sum of the squared difference values. First
In the second and third field prediction error calculation circuits 23 and 24, a prediction error signal is obtained between the same parity fields and using the same vector as described above.

The optimum vector determination circuit 25 calculates the sum of the two prediction error signals obtained by the first and second field prediction error calculation circuits 23 and 24, and stores it as a total prediction error. After searching all the search points by the address generation circuit 26, the optimal vector determination circuit 25 compares the total prediction error at each search point to find a position where the error value is minimum, and calculates the motion vector V1 and the prediction error. E1 is output.

In the present embodiment, it is possible to further perform motion detection on an interpolation pixel block with decimal point accuracy, thereby improving the accuracy of motion detection. As shown in FIG. 5B, the original pixel signals A and B or C and D are
Interpolation signals such as p or q can be created between upper and lower lines in the same field with a / 2 pixel precision to make an interpolation pixel block. In this case, as an interpolation signal between the upper and lower lines, a method of forming odd lines between odd lines and forming even lines between even lines is given by p = (A + B) /
2, q = (C + D) / 2,... In these calculations,
It is possible to round to improve accuracy. It is also possible to improve the motion detection accuracy by further interpolating between the upper and lower lines by 1/4 pixel accuracy. in this case,
As shown in FIG. 5B, s = (3) for s, t, u, and v points.
× A + B) / 4 to add an interpolation pixel. Note that the interpolation signal between pixels in the horizontal direction is limited to 1/2 pixel accuracy, and the interpolation pixel is created by averaging the left and right pixels.

In the case of FIG. 6, an interpolated pixel is created between adjacent lines and between adjacent pixels in each field by the intra-field interpolation circuit 22 to obtain an interpolation pixel block with decimal point precision. FIG. 7B shows a state in which interpolation pixels p and q are created between adjacent lines, and motion estimation is performed by obtaining a prediction error signal using the same vectors MV1 and MV2.

Next, the internal configuration of the near field motion detector 13 will be described with reference to the block diagram of FIG. Input block signal 10 and reference block signal 11
Are temporarily stored in the input block memory 20 and the reference block memory 21, respectively. In accordance with the address from the address generation circuit 26, each field data of the area for which motion is to be detected from the input block memory 20 and data of a search target area in a field located nearer to the input frame from the reference block memory 21 are compared. The first and second field prediction error calculation circuits 23 and 24 calculate the error.

In this case, with respect to an input block signal of 16 pixels × 16 lines, as shown in FIG. 9A, a parallel signal is applied to any of the odd field f1 and the even field f2 of the input screen. Vectors MV1 and MV
2, the reference data of the neighboring field (FIG. 9A)
Then, a prediction error signal is obtained between the prediction error signal and the field f2).
Then, in the optimal vector determination circuit 25, the first and second
The sum of the two prediction errors obtained by the field prediction error calculation circuit is obtained and stored as the total prediction error. By comparing the total prediction error at each search point, a position where the error value is minimum is obtained, and the motion vector V2 and the prediction error E2 are output. As the prediction error signal, a cumulative sum of absolute difference values or a cumulative sum of squared difference values can be used.

The motion vector for each field is based on one of the vectors, and the other vector uses a value converted by a temporal distance ratio. For example,
In FIG. 9A, MV1 is a basic vector, and MV2 is a vector obtained by converting the basic vector MV1 by a temporal distance ratio k. That is, MV2 = k × MV1.

In FIG. 9A, since the distance ratio is 1: 2, k = 2. In addition, since the distance ratio is uniquely determined according to the reference screen, only one of the motion vectors is encoded.

In order to improve the accuracy of motion detection,
Motion detection can be performed on an interpolation pixel block with decimal point precision. In this case, the intra-field interpolation circuit 2
In step 2, an interpolated pixel is created between adjacent lines and between adjacent pixels in a neighboring field, and is used as an interpolated pixel block. FIG. 9B illustrates a state in which interpolation pixels v and q are created between adjacent lines to perform motion prediction.

Next, the internal configuration of the inter-field interpolation motion detector 14 related to the present invention will be described with reference to FIG. The input block signal 10 and reference block signal 11 are temporarily stored in the input block memory 20 and the reference block memory 21, respectively. According to the address from the address generation circuit 26, the input block memory 20
From the reference block memory 21 and the field data of the search area from the reference block memory 21. The reference field data is obtained after the data synthesis between the fields is performed by the field synthesis circuit 27. As the prediction data, the first and second field prediction error calculation circuits 23 and 24 calculate the prediction error.

In this case, the block signal is 16 pixels × 16
As shown in FIG. 11A, for the input block signal of the line, as shown in FIG. 11A, the reference pixels w and x obtained by synthesizing the data of both the odd field and the even field in the reference screen and the odd field and the even field of the input screen are displayed. Between them, a prediction error signal is obtained using parallel vectors. Then, the optimum vector determination circuit 25 calculates the sum of the two prediction errors obtained by the first and second field prediction error calculation circuits and stores the sum as the total prediction error. By comparing the total prediction error at each search point, a position where the error value is minimum is obtained, and a motion vector V3 and a prediction error E3 are output. To combine the even field and the odd field data of the reference screen,
A simple average or an average of data weighted according to a temporal distance can be used. In this case, the motion vector can use the same parity, and the prediction error signal can be a cumulative sum of absolute difference values or a cumulative sum of difference square values.

The motion vector for each field is based on one of the vectors, and the other vector uses a value converted by a temporal distance ratio. For example,
In FIG. 11 (A), a basic vector is set between f1 on the input screen and f1 on the reference screen, and this is set as MV1 (first motion vector). Reference data required for f1 on the input screen is M
Conversion of the first motion vector according to the data at f1 of the reference screen by V1 (first prediction signal) and the data of f2 at the position where MV1 is projected onto f2 of the reference screen (temporal distance) (Third predicted signal) obtained by synthesizing the second predicted signal obtained by the above-described method.

Further, f2 of the input screen and f1 of the reference screen
If the vector between them is MV2, for MV2, M
A value obtained by converting V1 (first motion vector) by a temporal distance ratio k is used. That is, MV2 = k × MV1. In FIG. 11A, since the distance ratio is 2 to 3, k = 3 /
It becomes 2. The reference data required for f2 on the input screen is MV
2 (fourth prediction signal obtained by converting the first motion vector according to the temporal distance) and MV2 at the position where f2 of the reference screen is mapped to f2 of the reference screen.
(Sixth prediction signal) obtained by synthesizing the second data (the fifth prediction signal obtained using the first motion vector).

Further, since the distance ratio is uniquely determined according to the reference screen, only one of the motion vectors is encoded. In order to improve the accuracy of motion detection, motion detection can be performed on an interpolation pixel block with decimal point accuracy. In this case, an interpolated pixel is created by an intra-field interpolation circuit 22 between adjacent lines and between adjacent pixels in each field to form an interpolated pixel block. FIG. 11B shows a state in which interpolation pixels y and z are created between adjacent lines and between adjacent pixels, and motion estimation is performed.

In implementing the present invention, various modifications are possible. For example, the size of a block is 16 pixels ×
Various sizes such as 32 pixels × 32 lines are applicable without being limited to 16 lines. For a color signal block, for example, in the case of 8 pixels × 8 lines, a prediction signal may be created by halving both the horizontal motion vector and the vertical vector obtained by motion detection.

Next, a second embodiment of the present invention will be described. In this embodiment, as shown in FIG. 12, the same parity field motion detector 12, near field motion detector 13 and inter-field interpolation motion detector 14 are combined with a frame motion detector 17 and a field motion detector 18. It is. In this embodiment, the prediction error values E1, E2, E3, ER and EF detected by the detectors 12, 13, 14, 17 and 18 are input to the comparator 15. The comparator 15 selects the smallest prediction error value from these prediction error values and outputs a selection plug ZM. The selector 16 selects the motion vectors V1, V2, V3,... Of the motion detector having the smallest prediction error value based on the selection flag ZM.
VR or VF is selected and output as ZV.

Here, the internal configuration of the frame motion detector 17 will be described with reference to FIG. Here, the input block data 10 and the reference block data 11 are stored in the input block memory 20 and the reference block memory 21 respectively.
Is stored once. In accordance with the address from the address generation circuit 26, the frame data of the area for which motion is to be detected from the input block memory 20 and the frame data of the search area from the reference block memory 21 are extracted, and the error is calculated by the frame prediction error calculation circuit 29. .

In this case, as shown in FIG. 14A, in a frame screen F in which two fields (○ and ● are odd field data and □ and Δ are even field data) are alternately arranged, an input screen And a prediction error signal between the frame of the reference screen and the frame of the reference screen. The optimum vector determination circuit 25 compares the prediction error signal at each search point obtained by searching the reference screen with the address from the address generation circuit 26, obtains a position where this error is minimized, and obtains the motion vector VR. And the prediction error ER.

In order to improve the accuracy of motion detection,
Motion detection can be performed on an interpolation pixel block with decimal point precision. In this case, the intra-frame interpolation circuit 28
Then, an interpolated pixel is created between adjacent lines and between adjacent pixels in the same frame to be an interpolation pixel block with decimal point precision. FIG. 14B shows a state in which an interpolation pixel is created between adjacent lines and motion estimation is performed.

Next, the internal configuration of the field motion detector 17 will be described with reference to FIG. Here, the input block data 10 and the reference block data 11 are stored in the input block memory 20 and the reference block memory 2 respectively.
1 is stored once. In accordance with the address from the address generation circuit 26, the field data of the area where the motion is to be detected from the input block
From the field data for the search area,
The first field prediction error calculation circuit 23 and the second field prediction error calculation circuit 24 calculate the prediction error of each field.

In this case, as shown in FIG. 16A, different vectors (MV1 and MV2) are used for the odd field f1 and the even field f2 of the input screen, and the input data of the odd field or the even field is used. A prediction error signal is obtained between the reference data and the input data of the even field and the reference data of the even field or the odd field. The optimum vector determination circuit 25 calculates the sum of the two prediction errors obtained by the first and second field prediction error calculation circuits and stores the sum as a total predicted value. By comparing the total prediction error at each search point, a position where the error value is minimized is obtained, and a motion vector VF and a prediction error EF for the input field are output.

In order to improve the accuracy of motion detection,
Motion detection can be performed on an interpolation pixel block with decimal point precision. In this case, the intra-field interpolation circuit 2
In step 2, an interpolated pixel is created between adjacent lines and between adjacent pixels in each field to form an interpolated pixel block with decimal point precision. FIG. 16B shows a state in which an interpolation pixel is created between adjacent lines and motion estimation is performed.

According to the present embodiment, since the frame motion detector 17 and the field motion detector 18 are added, it is possible to further improve the prediction accuracy as compared with the first embodiment. However, in this case, an increase in the selection flag ZM of the motion detection method and an increase in the calculation time are expected.

Next, a third embodiment of the present invention will be described. In this embodiment, the same parity field motion detector 12, the near field motion detector 13 and the inter-field interpolation motion detector 14 are provided with the inverse parity field motion detection and the distant field motion detection as shown in FIGS. It combines field motion detection.

In this case, the inverse parity field motion detection in FIG. 17 uses the same vector for the odd field and the even field of the input screen, as opposed to the same parity field motion detection in FIG. Performs motion detection between reference data of an even field and input data of an even field.

Further, the far field motion detection in FIG. 18 is different from the near field motion detection in FIG. 9 in that the same vector is used for the odd field and the even field of the input screen, and the input data of either the odd field or the even field is used. , Motion detection is performed with reference data (field f1 in FIG. 18) of a temporally distant field.

In the present invention, the temporal distance or position between the reference screen and the input screen is arbitrary. For example, 6
It is possible to refer to a reference screen separated by a frame or to a reference screen located later in time. In the latter case, motion compensation in the reverse direction is performed temporally.

Also, the number of reference screens is free. For example, the present invention is used to obtain an optimal prediction screen for each of a plurality of reference screens located before and after the input screen. Then, a new screen synthesized by applying a time filter to each optimal prediction screen can be used as the prediction screen.

[0055]

According to the present invention as described above,
A specific reference field is set, a first motion vector between the specific reference field and the input field is used to determine a first prediction signal that predicts the input field from the specific reference field, and the specific reference field and By converting the magnitude of the first motion vector according to the ratio of the temporal distance between the input field and the temporal distance between the other reference field and the input field, the other reference field , A second prediction signal obtained by predicting the input field is obtained, and the first and second prediction signals are combined to obtain a third prediction signal of the input field. More specifically, when an input field having one parity is predicted by combining two reference fields each having one parity and the other parity, the same one parity is used from the reference field having one parity. Is predicted using the first motion vector, and the prediction from the reference field having the other parity to the input field having one parity is performed based on the distance between the fields by the magnitude of the first motion vector. Is performed using the second motion vector obtained by converting For this reason, the motion vector to be coded is only the first vector, the amount of information necessary for coding can be reduced, and coding efficiency can be greatly improved. As described above, since only one vector (first motion vector) needs to be coded per block, the load of the vector amount, which has conventionally been a problem in motion compensation of only the field signal, is reduced to half. It is possible to improve the image quality and reduce the amount of transmitted information. As an example of the effect, an ISO test video (Flower Garde
n, Bicycle) in the CCIR601 image format at a bit rate of 4 Mbit / s.
/ N ratio) is improved by 0.5 to 1.0 dB as compared with a system adaptively using frame motion compensation and field motion compensation.
The amount of motion vector information transmission was reduced by 30 to 60%.

[Brief description of the drawings]

FIG. 1 is a block diagram of a conventional motion compensation prediction apparatus for interlaced moving images.

FIG. 2 is a block diagram of a conventional motion detection unit.

FIG. 3 is a block diagram of a motion detection unit according to the first embodiment of the present invention.

FIG. 4 is an explanatory diagram showing an example of a configuration of block data of an input screen.

FIG. 5 is a configuration diagram of screen data showing a part of block data of an input screen and block data of a reference screen in a vertical direction and a time axis direction.

FIG. 6 is a block diagram showing a specific example of the same parity motion detector.

FIG. 7 is an explanatory diagram of the operation principle of the same parity motion detector.

FIG. 8 is a block diagram showing a specific example of a near field motion detector.

FIG. 9 is an explanatory diagram of the operation principle of the near field motion detector.

FIG. 10 is a block diagram showing a specific example of an inter-field interpolation motion detector.

FIG. 11 is an explanatory diagram of the operation principle of the inter-field interpolation motion detector.

FIG. 12 is a block diagram of a motion detection unit according to the second embodiment of the present invention.

FIG. 13 is a block diagram illustrating a specific example of a frame motion detector.

FIG. 14 is an explanatory diagram of the operation principle of the frame motion detector.

FIG. 15 is a block diagram showing a specific example of a field motion detector.

FIG. 16 is an explanatory diagram of the operation principle of the field motion detector.

FIG. 17 is an explanatory diagram of the operation principle of the inverse parity field motion detector used in the third embodiment of the present invention.

FIG. 18 is an explanatory diagram of the operation principle of the far field motion detector.

[Explanation of symbols]

 10 Input Screen 11 Reference Screen 12 Same Parity Field Motion Detector 13 Near Field Motion Detector 14 Inter-Field Interpolation Motion Detector 15 Comparator 16 Selector 71 Subtractor 72 Encoder 73 Quantizer 74 Dequantizer 75 Decoding Unit 76 adder 77 frame memory 78 motion detector 79 motion compensator 80 variable length encoder 81 multiplexer 84 frame motion detector 85 field motion detector 86 selector 87 comparator

Continuation of the front page (56) References JP-A-5-41861 (JP, A) JP-A-5-37915 (JP, A) JP-A-3-226193 (JP, A) 1991 Annual Meeting of the Institute of Television Engineers of Japan Proceedings of lectures, p. 313-314 1991 IEICE Spring National Convention Lecture Paper Volume 7, p. 64 1990 Image Coding Symposium (PC SJ90) 5th Symposium, pp. 175-177 IEICE Technical Report (IE 88-97), Vol. 88, No. 411, p. 47−54 (58) Field surveyed (Int.Cl. ⁷ , DB name) H04N ^7/ 24-7/68 H04N 11/04

Claims (7)

(57) [Claims] 1. A motion compensation prediction method for a moving image signal for a continuously input image signal, wherein a specific reference field is set, and a first motion between the specific reference field and the input field is set. A first prediction signal is obtained by predicting the input field from the specific reference field using a vector, and a temporal distance between the specific reference field and the input field, another reference field, and the input field are determined. By converting the magnitude of the first motion vector according to the ratio to the temporal distance between the second reference signal and the second reference signal, a second prediction signal that predicts the input field from the other reference field is obtained. First and second
A motion compensation prediction method for an interlaced moving image signal, wherein a third prediction signal of the input field is obtained by combining the prediction signals of 2. An interlace encoding method for encoding a prediction error screen, which is a difference between a prediction signal of an input field obtained by the motion compensation prediction method for an interlace video signal according to claim 1 and the input field. An encoding method of a moving image signal. 3. A method for predicting an input field having one parity from a reference field having one parity by using the first motion vector to convert the input field having one parity from the reference field having one parity. A first predicted signal is obtained, and a temporal distance between the reference field having the one parity and the input field having the one parity, and a reference field having the other parity and the one parity are provided. The input field having one parity is predicted from the reference field having the other parity by converting the magnitude of the first motion vector according to a ratio of the temporal distance to the input field. A second predicted signal obtained is obtained, and the first and second predicted signals are combined to hold the one parity. A third prediction signal of one input field is obtained, and a temporal distance between the reference field having the one parity and the input field having the one parity, the reference field having the one parity, and the other By converting the magnitude of the first motion vector according to the ratio of the temporal distance to the input field having parity, the input field having the other parity is converted from the reference field having the one parity. And a fifth prediction signal that predicts the input field having the other parity from the reference field having the other parity by using the first motion vector is calculated. Combining a fourth prediction signal and a fifth prediction signal to obtain a sixth prediction signal of the input field having the other parity. Motion compensated prediction method that interlaced moving image signals. 4. The input field having one parity is predicted using the third prediction signal, and the input field having the other parity is predicted using the sixth prediction signal. 4. The method of claim 3, wherein the method comprises: 5. A prediction error screen, which is a difference between a prediction signal of an input field obtained by the motion compensation prediction method of an interlaced video signal according to claim 3 and the input field, is encoded. Encoding method of an interlaced moving image signal. 6. A method for predicting an input field having one parity from a reference field having one parity by using a first motion vector to convert an input field having one parity from the reference field having one parity. A first predicted signal is obtained, and a temporal distance between the reference field having the one parity and the input field having the one parity, and a reference field having the other parity and the one parity are provided. The input field having one parity is predicted from the reference field having the other parity by converting the magnitude of the first motion vector according to a ratio of the temporal distance to the input field. A second predicted signal obtained is obtained, and the first and second predicted signals are combined to hold the one parity. A third prediction signal of one input field is obtained, and a temporal distance between the reference field having the one parity and the input field having the one parity, the reference field having the one parity, and the other By converting the magnitude of the first motion vector according to the ratio of the temporal distance to the input field having parity, the input field having the other parity is converted from the reference field having the one parity. And a fifth prediction signal that predicts the input field having the other parity from the reference field having the other parity by using the first motion vector is calculated. Motion compensated prediction for combining the fourth and fifth predicted signals to obtain a sixth predicted signal of the input field having the other parity Stage and coding apparatus interlaced moving picture signal, characterized in that a coding unit for encoding the first motion vector for the input frame. 7. The motion compensation prediction means predicts an input field having the one parity using the third prediction signal, and uses the sixth prediction signal for the input field having the other parity. 7. The apparatus according to claim 6, wherein the apparatus is configured to make predictions.