JP2003259373A - Moving picture compression/coding apparatus and motion vector detection method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a moving picture compression/coding apparatus capable of detecting a proper motion vector even when an image indicates a greater motion and setting a proper motion vector detecting range and to provide a motion vector detection method, a recording medium, and a program. <P>SOLUTION: The moving picture compression/coding apparatus includes: a motion vector detection means 12 for detecting a motion vector within a first motion vector detection range from a demodulated moving picture signal and a macro block moving picture signal; motion vector count means 14, 15, 16 for counting the number of first motion vectors which are the number of motion vectors located over the first outermost line which is the outermost line of a first motion vector detection range and the second outermost line or lines of a second motion vector detection range which is inside the first motion vector detection range, the second outermost line or lines being adjacent to the first outermost line, and a motion vector detection range decision means 13 for increasing the first motion vector detection range according to the number of the first motion vectors counted. <P>COPYRIGHT: (C)2003,JPO

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a moving picture compression coding apparatus for compressing and coding a moving picture, a motion vector detecting method therefor, a recording medium, and a program.

[0002]

2. Description of the Related Art In a moving picture compression coding apparatus, a motion vector detection apparatus is unavoidably increased in hardware scale in order to improve the accuracy of motion vector detection.
Therefore, the motion vector detection is performed in a mode in which the detection range is narrow but the detection accuracy is high, or in a mode in which the detection range is wide but the detection accuracy is low.

A conventional motion vector detecting device is shown in FIG. 10 (for example, refer to Patent Document 1). Reference numeral 101 is a reference frame signal input terminal for inputting a reference frame signal which is a current frame signal to a moving image compression encoder. , 102 are prediction frame signal input terminals for inputting the prediction frame signal which is the previous frame signal to the moving image compression encoder. 1
Reference numeral 03 denotes a wide area motion vector detector that detects a motion vector in a mode in which the detection range is wide but the detection accuracy is low.
Reference numeral 4 denotes a narrow area motion vector detector that detects a motion vector in a mode in which the detection range is narrow but the detection accuracy is high.
Is a comparator for comparing and evaluating the motion vector detection results obtained by the wide area motion vector detector 103 and the narrow area motion vector detector 104, and 106 is a wide area motion vector detector 103 based on the comparison result of the comparator 105. , Or a result of motion vector detection from the narrow area motion vector detector 104, and 107 is an output terminal for outputting the motion vector detected by the wide area motion vector detector.

The operation of the conventional motion vector detecting device configured as described above will be described. First, the reference frame signal input from the reference frame signal input terminal 101 passes through the low-pass filter 108 and the downsampling circuit 109, and the wide area motion vector detector 10
Input to 3. At the same time, the reference frame signal input from the reference frame signal input terminal 101 is also input to the narrow band motion vector detector 104. Similarly, the prediction frame signal input from the prediction frame signal input terminal 102 is input to the wide area motion vector detector 103 via the low pass filter 110 and the downsampling circuit 111. At the same time, the predicted frame signal input from the predicted frame signal input terminal 102 is also input to the narrow band motion vector detector 104. The motion vectors detected by the motion vector detectors 103 and 104 are compared and evaluated by the comparator 105, and the motion vector with the higher evaluation is output from the switch 106 to the output terminal 107.

However, in the configuration of the motion vector detecting device of FIG. 10, the number of motion vector detection ranges (hereinafter referred to as the number of modes) is used to detect a more appropriate motion vector.
If, for example, there are two, the hardware scale increases as compared with the case where the number of modes is one.

That is, if the number of motion vector detection ranges is set to, for example, a motion vector detection range having a narrow detection range but high detection accuracy and a motion vector detection range having a wide detection range but low detection accuracy, detection is performed. Two types of hardware are required: a narrow area motion vector detector 104 that has a narrow range but high detection accuracy, and a wide area motion vector detector 103 that has a wide detection range but low detection accuracy. Then, it is necessary to simultaneously perform motion vector detection for each motion vector detector, and independent motion vector detection circuits are required for the two motion vector detectors 103 and 104 respectively, and hardware such as a motion vector detection circuit is required. There was a problem that the scale became large.

In order to solve the problem of the conventional motion vector detecting device described with reference to FIG. 10, the moving picture compression encoding device shown in FIG. 11 is known (see, for example, Patent Document 2).

That is, FIG. 11 is a block diagram of a conventional moving picture compression coding apparatus. In FIG. 11, 301
Is a DCT circuit, 302 is a quantizer, and 303
Is an inverse quantizer, 304 is an inverse DCT circuit, 3
Reference numeral 05 is a frame memory, 306 is a motion compensation inter-frame prediction circuit, 307A is a motion detection device,
Reference numeral 308 is an intra-frame / inter-frame switching signal.
In addition, the motion detection device 307A uses the buffer memory 20.
1, an error calculation circuit 202, an error comparison circuit 203, and an address generation circuit 204.

The operation of the conventional image coding apparatus configured as described above will be described below. The first frame of coding, that is, the first frame is switched to intraframe coding by the intraframe / interframe switching signal 308, and intraframe coding is performed for each frame without taking a difference. That is, the image data is converted into transform coefficients by the DCT circuit 301 in units of two-dimensional blocks, the transform coefficients are quantized by the quantizer 302, and then sent to the transmission path. In general, images have a high correlation, so that when DCT is performed, energy concentrates on transform coefficients corresponding to low frequency components. Therefore, it is possible to minimize the image quality deterioration and reduce the data amount by coarsely quantizing the high frequency components that are visually inconspicuous and finely quantizing the low frequency components that are important components. The quantized transform coefficients sent to the transmission path are simultaneously returned to real-time data through the inverse quantizer 303 and the inverse DCT transform circuit 304, and stored in the frame memory 305.

On the other hand, the image after the second frame is switched to the interframe coding by the intraframe / interframe switching signal 308, the motion is compensated, and the difference from the image of the previous frame is taken to obtain each frame. The image signal difference between frames is encoded. That is, the motion-compensated inter-frame prediction circuit 306 calculates the predicted value of the image after the second frame based on the image data of the previous frame stored in the frame memory 305 and the motion vector of the two-dimensional block detected by the motion detection device 307A. Images generated and motion-compensated interframe prediction circuit 306 of the second and subsequent frames
The prediction error, which is the difference between the prediction value after the second frame and the prediction value generated in step 2, is converted into transform coefficients by the DCT circuit 301 in two-dimensional block units, and the transform coefficients are quantized by the quantizer 302, and then transmitted. Sent to the road. The quantized transform coefficients sent to the transmission path are simultaneously returned to real-time data through the inverse quantizer 303 and the inverse DCT transform circuit 304, and stored in the frame memory 305.

Next, the motion detecting device 307A will be described in detail. The motion detection device 307A is configured to obtain a motion vector between frames in a unit of a two-dimensional block using, for example, the well-known full search method. FIG. 12 is an explanatory diagram showing the operation of the motion detection device 307A. Hereinafter, the motion detection operation will be described with reference to FIG. In FIG. 12, reference numeral 311 denotes one two-dimensional block having the second frame, which is composed of a rectangular block of m pixels (horizontal direction) × n pixels (vertical direction). Reference numerals 312A and 312B are two-dimensional blocks of the first frame for performing error calculation, and their sizes are the same as those of the two-dimensional block 311. 313 is a motion vector obtained by motion detection,
Center coordinates of the two-dimensional block 311 and the two-dimensional block 31
It connects the center coordinates of 2B.

The two-dimensional block 311 in FIG.
It is a two-dimensional block having the center coordinates (x, y, 2) in the second frame, and the two-dimensional block is represented by the symbol S (x, y, 2) corresponding to the center coordinates. Also, the two-dimensional block 312A,
312B is the center coordinates (x, y, 1), (x
+ mx, y + my, 1) are two-dimensional blocks,
Similarly, the symbol S (x, y,
2), S (x + mx, y + my, 1). However, x represents the pixel coordinates in the horizontal direction with the center of the frame as the origin, y represents the pixel coordinates in the vertical direction with the center of the frame as the origin, and x,
The numbers 1 and 2 after y indicate frame numbers. Also, 3
Reference numeral 14 is a rectangular (horizontal direction 2h, vertical direction 2v) motion vector detection range indicating a two-dimensional block for calculating a motion vector, and xh is the center of the motion vector detection range (coordinates (x, y, 1) in the figure). ) Is the local pixel coordinate in the horizontal direction, and yv is the vertical pixel coordinate in the vertical direction with the center of the motion vector detection range (coordinate (x, y, 1) in the figure) as the origin.

The image data of the second frame is input to the buffer memory 201 at the same time when it is encoded between frames. The image data of the first frame is already stored in the buffer memory 201. Now, the reference is the two-dimensional block 311 of the second frame (current frame), and the motion vector 313 between the two-dimensional block 312B of the first frame (previous frame) and the two-dimensional block 311 of the second frame (current frame) is set. To detect. Buffer memory 2
The first and second frame images input to 01 are read in units of two-dimensional blocks of m × n pixels, and the motion vector is detected in units of two-dimensional blocks.

The procedure of detecting the motion vector using the coordinates will be specifically described below. Address generation circuit 20
4, the image data of the two-dimensional block S (x, y, 2) having the center coordinates (x, y, 2) in the second frame is read out,
The two-dimensional block S (x, y, 2) is taken as a reference block, and the motion between the reference block and the first frame is detected by the following procedure. As described above, the image data of the first frame is also stored in the buffer memory 201, and then the two-dimensional block S (x, y, 1) having the center coordinates (x, y, 1) in the first frame is stored. Each image data is read. In the error calculation circuit 202, the two two-dimensional blocks S (x, y, 2), S
The sum of squared errors of the amplitude of the image data at (x, y, 1) (hereinafter simply referred to as error) σ (x, y) (0,0) is calculated by [Equation 1], and the error comparison circuit 203 send.

[0015]

[Equation 1]

Next, the address generating circuit 204 outputs the m × n block adjacent to one pixel in the horizontal direction in the first frame, that is, the two-dimensional block S (x + 1, y, 1) having the center coordinates (x + 1, y, 1). Generate the address of 1). The error calculation circuit 202 similarly calculates σ (x, y) (+ 1,0) and sends it to the error comparison circuit 203.
In the error comparison circuit 203, σ (x, y) (0,0) and σ (x, y) (+ 1,
0) is compared and the smaller one is selected. Similarly, -h
The image data of the two-dimensional block is read while sequentially changing the address within the range of <xh <h, -v <yv <v, and σ
Calculate (x, y) (xh, yv).

The error comparison circuit 203 has a minimum error σ (x, y) (mx, m) from the error σ (x, y) (xh, yv) calculated above.
Select y) and output the addresses mx and my at the same time. Therefore, the motion vector 2 in the two-dimensional block S (x, y, 2)
13 is mv (mx, my). Hereinafter, in the second frame, by repeating the above operation for all of the two-dimensional blocks divided into a plurality, the motion vectors of all the two-dimensional blocks in the second frame are obtained.

The motion-compensated inter-frame prediction circuit 306 generates a motion-compensated prediction value for the second frame in units of two-dimensional blocks using the motion vector detected for each two-dimensional block in the second frame. For the image of the second frame, first, the difference between the image data of the first frame and the prediction value generated by the above-described method from the motion vector of the second frame, that is, the prediction error is calculated. After that, the above-described prediction error is encoded for each frame by the same method as in the first frame.

With the above-described structure, within the predetermined motion vector detection range of the previous frame centering on the position of the two-dimensional block obtained by dividing the current frame, the two-dimensional block having the same size as the two-dimensional block obtained by dividing the current frame is displayed. The image data of the three-dimensional block is extracted while sequentially changing the position, and the error between the image data of each two-dimensional block within the predetermined motion vector detection range of the previous frame and the image data of the divided two-dimensional block of the current frame and The current frame is divided into two by performing error comparison on two-dimensional blocks having different positions within the predetermined motion vector detection range of the previous frame.
2 within the predetermined motion vector detection range of the previous frame in which the error of the image data is the smallest for the three-dimensional block
Searching the position of the dimensional block and dividing the current frame 2
A two-dimensional block obtained by dividing the current frame from the position of the two-dimensional block and the position of the two-dimensional block within the predetermined motion vector detection range of the previous frame having the smallest image data error with respect to the two-dimensional block obtained by dividing the current frame. A motion vector indicating the motion on the screen from the previous frame of will be calculated.

According to the above method, since the prediction error is coded, the energy is reduced compared to the case where the image data is directly coded like the intra-frame coding, and the code with higher efficiency is obtained. Can be realized.

Next, the operation after the third frame will be described. When calculating the motion vector of each frame after the third frame, the previous frame (in the case of the third frame,
The motion vector of the second frame) is input to the CPU 205 as the motion vector detection range determination information that is detected in time before and indicates the magnitude of the motion of the image, and the arithmetic processing as described below is performed to determine the address. The motion vector detection range is changed by controlling the generation circuit 204.

FIG. 13 is a flow chart showing the processing operation of the CPU 5. Referring to FIG. 13, in step 21, the motion vectors of all the two-dimensional blocks of the previous frame (for example, the second frame) are read, and in step 22, the motion vector indicating the maximum value h in the horizontal direction of the motion vector detection range at normal time. Count the number of. In step 23, it is determined whether or not the number is 50 or more of all blocks. If the number is 50% or more of all blocks, it is determined that the image motion is large and the horizontal motion vector detection range is expanded to, for example, 2h. In order to double the motion vector detection range, as shown in step 24, the input to the error calculation circuit 2 is thinned out every sample, that is, 1 /
The address generation circuit 4 is controlled so as to be subsampled to 2 and input. By doing so, the amount of calculation for each two-dimensional block is halved, so that even if the motion vector detection range is doubled, the total amount of calculation becomes equal to that when the motion vector detection range is not widened. . Further, as shown in step 25, the number of motion vectors exceeding h / 2 is also counted at the same time, and it is determined in step 26 whether the number of motion vectors exceeding h / 2 is 10% or less.
When it is 0% or less, the motion vector detection range is set to h / 2, assuming that there is little motion. In this case, the data is input to the error calculation circuit 2 without being thinned (step 27). The motion vector exceeding h is less than 50%, and h /
When the number of motion vectors exceeding 2 exceeds 10%, the motion vector detection range is not changed and subsampling is not performed.

By the above operation, when the motion of the image is large, the motion vector detection range can be expanded without increasing the calculation amount. In general, when motion detection is performed from a subsampled image, the motion detection accuracy decreases, leading to image quality deterioration. However, when the motion is large, the image quality deterioration due to the non-follow of the motion has a larger effect, and thus the image quality is improved by expanding the motion vector detection range even in the sub-sampled image.
Further, when the motion is small, the motion is detected by the image that is not subsampled, so that the image quality is not deteriorated and the motion vector detection range is further narrowed, so that the processing time required for the search can be shortened.

In this way, the motion vector detection range can be changed according to the motion of the image, large motion can be supported, the inter-frame difference can be reduced, and the image quality is not deteriorated. Moreover, since the amount of calculation for calculating the motion vector does not increase, the amount of hardware for calculating the motion vector does not increase.

[0025]

[Patent Document 1] Japanese Patent Laid-Open No. 9-224249

[Patent Document 2] Japanese Unexamined Patent Publication No. 10-23420

[0026]

However, the conventional moving picture compression coding apparatus described with reference to FIG. 11 cannot detect an appropriate motion vector for an image having a large motion, and thus a more appropriate motion. It is difficult to set the vector detection range.

That is, in the conventional moving picture compression coding apparatus described in FIG. 11, the motion vector detection range 320 is different from the motion vector detection range 320 as shown in FIG.
The motion vector detection range 320 is expanded when the number of motion vectors P on the outermost periphery of the number of blocks becomes 50% or more of the total number of blocks. That is, only the motion vector P on the outermost periphery of the motion vector detection range 320 is detected. However, the motion vector detection range 320
There is a possibility that a more appropriate motion vector than the motion vector P on the outermost periphery of the vector exists outside the motion vector detection range 320. Even in such a case, the conventional moving image compression encoding apparatus described in FIG. 11 detects and uses the motion vector P instead of detecting the appropriate motion vector.

That is, the conventional moving picture compression coding apparatus cannot detect an appropriate motion vector for an image with a large motion, and it is difficult to set an appropriate motion vector detection range. There is a problem that exists.

In consideration of the above problems, the present invention is a moving image compression code capable of detecting an appropriate motion vector even in an image having a large motion and setting an appropriate motion vector detection range. It is an object of the present invention to provide an encoding device, a motion vector detecting method, a recording medium, and a program.

[0030]

In order to solve the above-mentioned problems, the first aspect of the present invention subdivides an input moving picture image into N (where N is a natural number of 2 or more) per frame. Macroblock generating means (2) for generating a macroblock moving image signal, and code decoding means (18, 17, 3) for compressing the macroblock moving image signal and then decoding it to generate a decoded moving image signal. 4, 9, 10, 1
9, 20, 11), a motion vector detection means (12) for detecting a motion vector within a first motion vector detection range from the decoded video signal and the macroblock video signal, and the detected motion vector. Of the motion vectors, a first outermost line that is the outermost line of the first motion vector detection range and a second outermost line of the second motion vector detection range that is inside the first motion vector detection range. The motion vector counting means (1 that counts the number of motion vectors between the outermost line of 2 as the number of first motion vectors
4, 15, 16) and a motion vector detection range determining means (13) for expanding the first motion vector detection range based on the counted number of the first motion vectors. It is an oxidizer.

In the second aspect of the present invention, the motion vector counting means (14, 15, 16) includes a motion vector within a third motion vector detection range inside the second motion vector detection range. Is counted as the number of second motion vectors, and the motion vector detection range determination means (13) reduces the first motion vector detection range based on the counted number of the second motion vectors. The video compression encoding apparatus according to the first aspect of the present invention.

Further, in a third aspect of the present invention, the motion vector detection range determining means (13) is configured to count the first
If the number of motion vectors is larger than a predetermined threshold value, the first motion vector detection range is expanded, and if it is smaller than the predetermined threshold value, the first motion vector detection range is not expanded or the first motion vector is detected. It is the moving picture compression coding apparatus of the first aspect of the present invention which does not change the vector detection range.

According to a fourth aspect of the present invention, the motion vector detection range determining means (13) is configured to count the first
Is the moving image compression encoding apparatus according to the first aspect of the present invention, which enlarges the expansion rate of the first motion vector detection range as the number of motion vectors increases.

Further, in a fifth aspect of the present invention, the motion vector detection range determining means (13) is configured to count the second vector.
The moving picture compression encoding apparatus according to the second aspect of the present invention, which increases the reduction rate of the first motion vector detection range as the number of motion vectors increases.

In the sixth aspect of the present invention, the motion vector detection range determining means (13) has a plurality of types of motion vector detection ranges in advance, and the motion vector detection ranges are counted from the plurality of types of motion vector detection ranges. The moving image compression encoding apparatus according to the first aspect of the present invention is such that a larger motion vector detection range is selected as the number of the first motion vectors is larger and is set as the first motion vector detection range.

In the seventh aspect of the present invention, the motion vector detection range determining means (13) has a plurality of types of motion vector detection ranges in advance, and the motion vector detection ranges are counted from the plurality of types of motion vector detection ranges. In addition, the moving image compression encoding apparatus according to the second aspect of the present invention is such that a larger motion vector detection range is selected as the number of the second motion vectors is increased, and the smaller motion vector detection range is selected as the first motion vector detection range.

According to an eighth aspect of the present invention, the motion vector detection range determining means (13) updates the first motion vector detection range every P frames, or n P frames (however, not shown). , N ≦ N, which is a natural number), and when the first motion vector detection range is updated, the motion vector detection range determining means determines the P
A number obtained by dividing the number of counted first motion vectors of a frame or of the division unit by the number of macroblock moving image signals existing in the P frame or of the division unit is equal to or more than a predetermined threshold value. In this case, the first motion vector detection range is expanded, and the motion vector detection range determination means (13) is provided. The first motion vector detection range is updated for each P frame or for each division unit obtained by dividing the P frame into n (where n ≦ N is a natural number). Is updated, the motion vector detection range determining means determines the number of the counted second motion vectors in the P frame or in the division unit to be in the P frame or in the division unit. When divided by the number of macroblocks moving image signal is present, equal to or greater than a predetermined threshold value,
The moving image compression encoding apparatus according to the first aspect of the present invention reduces the first motion vector detection range.

Further, in a tenth aspect of the present invention, the motion vector detecting means, when expanding the first motion vector detection range, also expands the second motion vector detection range. , 6 and 8 according to the present invention.

In the eleventh aspect of the present invention, the motion vector detecting means also reduces the third motion vector detection range when reducing the first motion vector detection range. , 9 according to the present invention.

The twelfth aspect of the present invention compresses and encodes a macroblock moving image signal generated by subdividing an input moving image video into N (where N is a natural number of 2 or more) per frame. A motion vector detecting step of detecting a motion vector within a first motion vector detection range from a decoded moving image signal generated by decoding afterwards and the macroblock moving image signal; and among the detected motion vectors, A first outermost line which is the outermost line of the first motion vector detection range, and a second outermost line of the second motion vector detection range which is inside the first motion vector detection range.
A motion vector counting step of counting the number of motion vectors between the outermost line of the first motion vector and the outermost line of the first motion vector as the number of first motion vectors; One or a plurality of second outermost lines that are the outermost lines of the second motion vector detection range inside the first motion vector detection range and that are adjacent to the first outermost line. A motion vector counting step of counting the number of first motion vectors, which is the number of motion vectors on the outermost line, and the first motion vector detection based on the counted number of the first motion vectors. And a motion vector detection range determining step of expanding the range.

The thirteenth aspect of the present invention is the motion vector detecting method of the twelfth aspect of the present invention, in which an input moving image is subdivided into N (where N is a natural number of 2 or more) per frame. Vector for detecting a motion vector within a first motion vector detection range from a decoded moving image signal generated by compressing and encoding the generated macroblock moving image signal and the macroblock moving image signal A detection step, a first outermost line which is an outermost line of the first motion vector detection range among the detected motion vectors, and a second outermost line which is inside the first motion vector detection range.
A motion vector counting step of counting, as the number of first motion vectors, the number of motion vectors between the second outermost line which is the outermost line of the motion vector detection range of
And a motion vector detection range determining step of expanding the first motion vector detection range based on the counted number of the first motion vectors.

The 14th aspect of the present invention is a recording medium carrying the program according to the 13th aspect of the present invention, which can be processed by a computer.

[0043]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of the present invention will be described below with reference to the drawings.

According to the embodiment of the present invention, for example, the motion vector detection range adaptively obtained based on the motion vector detected by the motion vector detection unit (means) is fed back to the motion vector detection unit (means). Since the configuration is provided, the motion vector detection range for detecting the motion vector by the motion vector detection unit (means) can be set in accordance with the motion of the input moving image, and the motion vector for detecting a more appropriate motion vector. Even when there are a plurality of detection ranges (that is, the number of modes), it is possible to improve the accuracy in detecting a motion vector without increasing the circuit scale.

Further, according to the embodiment of the present invention, for example, since the motion vector detection range is fed back to the motion vector detecting unit in a unit of subdividing the input moving image video, for example, an input moving image of one frame or the like is provided. The motion vector detection range can be appropriately set in the motion vector detection unit according to the motion of the input moving image video in a unit of the image video, and the setting of the highly accurate motion vector detection range can be simplified.

Further, according to the embodiment of the present invention, for example, referring to the result of the motion vector detection range obtained adaptively, the motion vector detection range actually applied from a plurality of types of motion vector detection ranges provided in advance. Since it has a configuration for selecting, it is possible to freely update the motion vector detection range set in the motion vector detection unit from the plurality of types according to the input moving image, for example, according to the user's intention such as preference. Motion vector detection can be achieved. Further, it is possible to achieve motion vector detection in which the motion vector detection range set in the motion vector detection unit matches the motion of the input moving image, for example, the user's intention.

Further, according to the embodiment of the present invention, for example, the feedback means returns the motion vector detection range determined by the motion vector detection range determination means to the motion vector detection means and the switching area generation means. Therefore, the setting of the motion vector detection range can be determined more in accordance with the speed of movement of the input moving image video, and the immediacy of the motion vector detection range that matches the motion of the input moving image video can be improved.

Further, according to the embodiment of the present invention, for example, (the number of motion vectors existing in the motion vector switching area) / (the number of macroblocks existing in n periods) is equal to or more than a predetermined threshold value. In this case, since the motion vector detection range is switched and the switched motion vector detection range is fed back to the motion vector detection means and the switching area generation means, it is possible to reduce the amount of generated code when encoding the input moving image. , It is possible to speed up the detection of the motion vector according to the motion of the input moving image.

(First Embodiment) FIG. 1 shows a first embodiment of the present invention.
FIG. 3 is a block diagram showing the configuration of a moving picture compression encoding apparatus according to the embodiment of the present invention.
This is an example showing the case of the True Experts Group) method. 1 is an input terminal, 2 is a frame rearranger, 3 is a discrete cosine transform (hereinafter, DC
(T), 4 is a quantizer, 5 is a variable length encoder, 6 is a buffer memory, 7 is an output terminal, 8 is a rate controller, and 9 is a rate controller. Inverse quantizer, 10 is an inverse DCT device, 11 is a frame memory, 12 is a predictor, 13 is a detection range determiner, 14 is a switching area determiner, and 15 is a comparison. , 16 is a counter, 17 is a subtractor, 1
Reference numeral 8 is a changeover switch, 19 is an adder, and 20 is a switch.

The frame rearranger 2 of the present embodiment is an example of the macroblock generating means of the present invention, and the changeover switch 18, the subtractor 17, the DCT unit 3, the quantizer 4, of the present embodiment is used. The inverse quantizer 9, the inverse DCT device 10, the adder 19, the switch 20, and the frame scale 11 are examples of the code decoding means of the present invention, and the predictor 1 of the present embodiment.
2 is an example of the motion vector detecting means of the present invention, and the switching area determiner 14, the comparator 15, and the counter 16 of the present embodiment are examples of the motion vector counting means of the present invention, and The detection range determiner 13 is an example of the motion vector detection range determination means of the present invention.

The operation of each block configured as described above will be described. The original image signal input from the input terminal 1 is a video signal in which the audio signal and the video signal are separated in advance from the video and audio signal. The video signal is once rearranged into frames by the frame rearrangement unit 2 and then the original image video signal in a unit (hereinafter referred to as macroblock unit) obtained by subdividing the frame into a predetermined number of pixels is processed by the frame rearrangement unit 2. The data is output to the changeover switch 18 in the rearranged order (hereinafter referred to as decoding order). The changeover switch 18 outputs an original image video signal in macro block units (hereinafter, referred to as macro block moving image signal) as it is, or subtracts it from the macro block moving image signal with a motion compensation prediction image signal by a subtractor 17. Or select.

First, the case where the changeover switch 18 selects the macroblock moving image signal as it is will be described.
When the macroblock moving image signal output from the changeover switch 18 is an I picture, the DCT signal subjected to the discrete cosine transform in the DCT unit 3 is output to the quantizer 4. The quantizer 4 outputs a quantized signal having a reduced amount of information to the variable length encoder 5 and the inverse quantizer 9 by performing quantization with a predetermined quantized value fed back from the rate controller 8. .

The quantized signal input to the variable length encoder 5 is output to the buffer memory 6 as an encoded signal encoded by the variable length encoder 5, and is extracted from the output terminal 7 in the buffer memory 6. The coded signal is stored up to and the generated code amount is output to the rate controller 8. The rate controller 8 feeds back the quantized value based on the generated code amount to the quantizer 4. The encoded signal extracted from the output terminal 7 is multiplexed with the audio signal by a system encoder (not shown).

On the other hand, the quantized signal input to the inverse quantizer 9 is the inverse quantized signal which is inversely quantized with a predetermined quantized value.
Output to the CT device 10. The inverse DCT device 10 outputs an inverse DCT signal obtained by subjecting the input quantized signal to inverse discrete cosine processing. When the changeover switch 18 selects the macroblock moving image signal as it is, like the I picture, the switch 20 is turned off in conjunction with the changeover switch 18.
In this state, the adder 19 does not add the inverse DCT signal to the frame memory 11 and stores a reference video signal (hereinafter, referred to as a macroblock reference signal) in macroblock units until one frame is formed. In the P picture, a motion vector that minimizes the difference between the frame-based reference video signal stored in the frame memory 11 for one frame (hereinafter referred to as a frame reference signal) and the macroblock moving image signal from the frame rearranger 2. Is detected by the predictor 12 to detect the motion vector detection range, and at the same time, the motion vector and the video signal after motion compensation prediction (hereinafter referred to as the predicted video signal) are output.

A case where the changeover switch 18 is a P picture or a B picture in which the subtractor 17 selects the difference signal between the macroblock moving image signal and the predicted video signal will be described. In the case of a P picture, the difference signal obtained by subtracting the predicted video signal based on the immediately preceding I picture or P picture from the macroblock moving image signal is output to the DCT unit 3, and the DCT signal is output to the quantizer 4. One of the quantized signals output from the quantizer 4 is stored in the buffer memory 7 through the variable-length encoder 5 and the buffer memory 6 until it is extracted from the output terminal 7, and the generated code amount is controlled by the rate controller 8 And the quantized value is fed back to the quantizer 4. Buffer memory 6
The encoded signal stored in is output from the output terminal 7 to the system encoder in the same manner as described above.

The other of the quantized signals is the inverse quantizer 9, inverse D
It is input to the adder 19 via the CT unit 10. The switch 20 is turned on in association with the changeover switch 18, and the I picture or P picture immediately before being subtracted by the subtractor 17 is added to the inverse DCT signal output from the inverse DCT unit 10 to obtain a macroblock reference signal. The macroblock reference signal added by the adder 19 is stored in the frame memory 11 until one frame is obtained, and the predictor 12 performs a motion in which the difference signal is minimized from the frame reference signal from the frame memory 11 and the macroblock moving image signal. The vector is detected within the motion vector detection range, and the motion vector and the predicted video signal as shown in FIG. 2 are output.

When the macroblock moving picture signal is a B picture, it is the same as the P picture except that the subtracter 17 takes the difference between the predicted video signal based on the preceding or following I picture or P picture and the macroblock moving picture signal. Is. However, considering B-pictures as well, B-pictures refer to the preceding and subsequent pictures as described above, so the accuracy is not improved despite the complexity of the algorithm for updating the motion vector detection range in frame units. In the form of B
If it is a picture, an algorithm is adopted that ignores it until the next P picture is selected.

One of the signals output from the predictor 12 thus obtained is the subtractor 17 for the next macroblock moving image signal.
Is used as a predictive video signal for subtraction in step S1, and the other uses a motion vector in macroblock units to the comparator 15 in order to compare and verify whether the motion vector is within the motion vector detection range as shown in FIG. Output. Region D in FIG. 3 indicates a region where the motion vector detection range is narrowed, and region U indicates a region where the motion vector detection range is widened. That is, the motion vector V _ij corresponding to the macroblock C _ij detected by the predictor 12 shown in FIG. 2 exists in either range of the motion vector switching area D or U output from the switching area determining unit 14. It is compared and verified by the comparator 15 to adaptively obtain the macroblock switching signal and output to the counter 16.

The motion vector detection range shown in FIG. 3 will be described in more detail. FIG. 4 is a diagram for explaining the motion vector detection range shown in FIG. 3 in more detail. Figure 4 (a)
Indicates a motion vector detection range candidate, and in the present embodiment, five motion vector detection range candidates A
There are 1, A2, A3, A4 and A5. These motion vector detection range candidates are stored in the detection range determiner 13. The motion vector detection range used when the predictor 12 detects the motion vector and when the switching area determiner 14 determines the motion vector switching area is 5 or less.
Motion vector detection range candidates A1, A2, A3, A
Any one of A4 and A5 is selected and used.

Now, the motion vector detection range candidates A1, A
Of 2, A3, A4, and A5, A3 is actually used as the motion vector detection range.

As shown in FIG. 4B, the outermost line l3, which is the outermost line of the motion vector detection range A3, and the motion vector detection range A3 'inside the motion vector detection range A3.
The area between the outermost line l3 'and the outermost line l3' corresponds to the area U described in FIG. The area U in FIG. 3 is determined by the switching area determiner 14. Then, as described later, when the motion vector is in the area U and the predetermined condition is satisfied, the motion vector detection range A3 is expanded. At this time, the motion vector detection range A
3 ′ and A3 ″ are also processed to be enlarged.

Similarly, as shown in FIG. 4B, the area inside the outermost line l3 ″, which is the outermost line of the motion vector detection range A3 ″ inside the motion vector detection range A3 ′, is shown in FIG. This corresponds to the area D described in. Region D in FIG. 3 is
If it is determined by the switching area determiner 14 and if a motion vector is present in the area D as described later and a predetermined condition is satisfied, the motion vector detection range A3 is reduced. At this time, the motion vector detection ranges A3 ′ and A3 ″ are simultaneously processed so as to be reduced.

The switching area determiner 14 determines the area U and the area D in FIG. 3 according to the motion vector detection range.

In this embodiment, since the motion vector detection range is switched only for the motion vector based on the P picture, the comparator 15 operates only when the P picture is encoded, but the B picture is also operated. B to consider
It goes without saying that it also works when encoding a picture.

The comparator 15 determines whether the motion vector V _ij corresponding to the macroblock C _ij is in the area U of FIG. 3 and whether it is in the area D, and the determination result is determined as the macroblock. Counter 1 as switching signal
Output to 6.

When the macroblock switching signal is input, the counter 16 indicates the area when the macroblock switching signal indicates that the motion vector V _ij corresponding to the macroblock C _ij is in the area U in FIG. When the count value corresponding to U is incremented by 1, and when the macroblock switching signal indicates that the motion vector V _ij corresponding to the macroblock C _ij is in the area D of FIG. Increment the corresponding count value by 1.

In this way, the counter 16 counts the count value corresponding to the area D and the count value corresponding to the area U for one frame, and the counter 16 outputs the count result in a frame-based switching signal (hereinafter referred to as a frame switching signal). Is output to the detection range determiner 13. When the frame switching signal is input, the detection range determiner 13 adaptively determines the motion vector detection range on a frame-by-frame basis.

That is, the detection range determiner 13 is shown in FIG.
The motion vector detection range candidates A1, A2, shown in (a),
It is determined by selecting the motion vector detection range that is actually used from A3, A4, and A5.

When the motion vector Q is in the area D as shown in FIG. 5A, the detection range determiner 13 detects the motion vector detection range A4 as shown in FIG. 5B.
The motion vector detection range is reduced by selecting. More specifically, the detection range determiner 13
Is a predetermined threshold value obtained by dividing (the number of motion vectors existing in the motion vector switching area D) by (the number of macroblocks existing in one frame period) based on the frame switching signal input from the counter 16. When the above is reached, the motion vector detection range is switched to the motion vector switching area A4. At this time, the motion vector detection range A3 ′,
A3 ″ is switched to A4 ′ and A4 ″, respectively. In this way, the detection range determiner 13 reduces each motion vector detection range. Then, when the detection range determiner 13 determines the motion vector detection range to be the motion vector detection range A4, the determined motion vector detection range is set to the switching area determiner 1
4 and predictor 12. The switching area determiner 14 is
In accordance with the determination, the motion vector switching areas D and U are determined as shown in FIG.

The detection range determiner 13 is shown in FIG.
As shown in FIG. 6, when the motion vector R is in the area U, the motion vector detection range A2 is selected as shown in FIG. 6B to expand the motion vector detection range. More specifically, the detection range determiner 13
Is a predetermined threshold value obtained by dividing (the number of motion vectors existing in the motion vector switching area U) by (the number of macroblocks existing in one frame period) based on the frame switching signal input from the counter 16. When the above is reached, the motion vector detection range is switched to the motion vector detection range A2. At this time, the motion vector detection range A3 ′,
A3 ″ is switched to A2 ′ and A2 ″, respectively. In this way, the detection range determiner 13 expands each motion vector detection range. When the detection range determiner 13 determines the motion vector detection range to be the motion vector detection range A2, the determined motion vector detection range is set to the switching area determiner 1
4 and predictor 12. The switching area determiner 14 is
In accordance with the determination, the motion vector switching areas D and U are determined as shown in FIG. 6 (b).

Further, the detection range determiner 13 divides (the number of motion vectors existing in the motion vector switching area D) by (the number of macroblocks existing in one frame period) is smaller than a predetermined threshold value, If the value obtained by dividing (the number of motion vectors existing in the motion vector switching area U) by (the number of macroblocks existing in one frame period) is smaller than a predetermined threshold value, the motion vector detection range is expanded or reduced. There isn't. That is, the motion vector detection range is not changed.

The motion vector detection range fed back to the predictor 12 is used as an optimum motion vector detection range in frame units, and is used as a motion vector detection range in predicting a motion vector in the next frame unit in the predictor 12. To be

For example, the detection range determiner 13 is shown in FIG.
As shown in FIG.
If it is decided to, the predictor 12
Uses the motion vector detection range A4 when predicting the motion vector.

Similarly, the detection range determiner 13 is shown in FIG.
As shown in FIG.
If it is decided to, the predictor 12
Uses the motion vector detection range A2 when predicting the motion vector.

The same operation as above is performed in the next frame unit, and the motion vector detection range used in the predictor 12 is adaptively updated one after another. In the present embodiment, the above operation is performed for each P frame. That is, FIG.
Shows the timing of updating the motion vector detection range. The motion vector detected in the P frame 20 is used by the detection range determiner 13 to determine the motion vector detection range of the next P frame 21. As described above, the moving picture compression coding apparatus according to the present embodiment switches the motion vector detection range for each P frame.

In the case of an input moving image video having a particularly large motion, in the conventional moving image compression coding apparatus described in FIG. 11, only the motion vector P on the outermost periphery of the motion vector detection range 320 is used. Since it has been detected, even if a motion vector more appropriate than the motion vector P on the outermost periphery of the motion vector detection range 320 exists outside the motion vector detection range 320, such a motion vector is detected and used. I couldn't. Even in such a case, the conventional moving image compression encoding apparatus described in FIG. 11 detects and uses the motion vector P instead of detecting the appropriate motion vector.

On the other hand, in the moving picture compression coding apparatus of the present embodiment, when expanding the motion vector detection range, the area U shown in each of FIGS. 3, 4, 5, and 6 is used. The riding motion vector is taken into consideration. Therefore, even if there is a proper motion vector outside the motion vector detection range by the conventional technique and such a proper motion vector cannot be detected, the motion vector is set to the region U as in the present embodiment. By taking into consideration the above, it becomes possible to detect an appropriate motion vector that could not be detected by the conventional technique.

As described above, according to the present embodiment, it is possible to detect an appropriate motion vector even in an input moving image having a large motion, and set an appropriate motion vector detection range. become able to do.

As described above, the moving picture compression coding apparatus according to the present embodiment moves in parallel with the processing operation of the motion vector detecting means 21 for detecting the motion vector of the moving picture signal by compression coding. Since the motion vector detection range for detecting a vector is replaced with the optimized range in the unit of the previous frame, the hardware scale of the circuit or the like provided to the motion vector detection means 21 is not increased.
There is an effect that the detection of the motion vector can be optimized. Also,
It is possible to detect an appropriate motion vector even in an image with large motion, and set an appropriate motion vector detection range.

Although the detection range determiner 13 selects the motion vector detection range to be actually used from the five motion vector detection range candidates in this embodiment, the present invention is not limited to this. The actual motion vector detection range may be selected from the three motion vector detection range candidates,
The actual motion vector detection range may be selected from the seven motion vector detection range candidates. The detection range determiner 13 of the present embodiment stores a plurality of motion vector detection range candidates, and it suffices to select the motion vector detection range to be actually used from among the candidates.

Furthermore, in the present embodiment, the detection range determiner 13 has been described as selecting the motion vector detection range to be actually used from the five motion vector detection ranges, but the present invention is not limited to this. The detection range determiner 13 may increase the expansion rate of the motion vector detection range as the number of motion vectors existing in the motion vector switching area U increases.

Further, in this case, the detection range determiner 13
The larger the number of motion vectors existing in the motion vector switching area U, the larger the motion vector detection range may be selected from the motion vector detection ranges held in advance, and the detection range determiner 13 may detect the motion vector in advance. It is also possible to generate a larger motion vector detection range as the number of motion vectors existing in the motion vector switching area U increases without holding the range.

The detection range determiner 13 may increase the reduction ratio of the motion vector detection range as the number of motion vectors existing in the motion vector switching area D increases.

In this case, the detection range determiner 13
The larger the number of motion vectors existing in the motion vector switching area D, the smaller the motion vector detection range may be selected from the motion vector detection ranges held in advance, and the detection range determiner 13 may detect the motion vector in advance. It is also possible to generate a smaller motion vector detection range as the number of motion vectors existing in the motion vector switching region D increases without holding the range.

The moving picture compression coding apparatus according to the present embodiment, as shown in FIG. 8A, FIG. 8B, and FIG. When the motion vector approaches the unit, it is detected. On the contrary, when the motion vector is wide, the motion vector detected by the widened part is thinned out. That is, when the detection range is wide such as the motion vector detection range A1 as shown in FIG. 8A, the motion vector regarding the thinned pixels is detected as shown by the black mark, and conversely, FIG. ) Motion vector detection range A5
If the detection range is narrow, as shown in,
The motion vector is detected in pixel units. Therefore, even if the motion vector detection range is widened, the pixels for which the motion vector is calculated are thinned out according to the width, so that the calculation amount for motion vector detection does not increase.

As shown in FIG. 4, when a plurality of motion vector detection ranges are provided and a motion vector detection range is selected from the plurality of types of motion vector detection ranges, the motion vector detection range is input to the input image. Can be optimized by appropriately enlarging / reducing according to the size of the movement of
The motion vector detection accuracy can be improved and the generated code amount can be reduced, and the high quality of the moving image after decoding can be achieved.

Further, the circuit such as the storage means required for the motion vector detection can be of a scale corresponding to the narrowest range of the motion vector detection range, and the high quality decoding can be achieved due to the improvement of the motion vector detection accuracy. It is also possible to reduce the cost of the device that can realize the image.

From the motion vector detection range 13 in the above embodiment, a switching area determiner 14 for generating a motion vector detection range switching area according to the motion vector detection range.
And a comparator 15 for comparing the motion vector detection range switching area with the detected motion vector to determine whether the motion vector exists in the motion vector switching area, and a counter 16 for comparing with the motion vector switching area. When a configuration is provided in which the determination signal of the output signal of the device 15 is stored and the motion vector detection range is determined based on the determination signal stored in the counter 16, the motion vector detection range of the motion vector detected by the motion vector detection means 21. Can follow the movement of the input moving image video, and the immediacy of the motion vector detection range according to the movement of the input moving image video can be improved.

In this embodiment, the motion vector detection range output from the detection range determiner 13 to the predictor 12 has been described as being updated on a frame-by-frame basis, but the present invention is not limited to this. Although it has been described that the motion vector detection range is adaptively determined for each frame, the present invention is not limited to this.

The motion vector detection range output from the detection range determiner 13 to the predictor 12 may be updated in n (n is a natural number satisfying n ≦ N) periods. However,
Let N be the total number of macroblocks present in one frame,
When one frame is divided into a plurality of pieces, the total number of macro blocks in one division unit is n. In this case, the counter 16 is configured to store the number of motion vectors existing in the motion vector switching area for n periods, and stores (the number of motion vectors existing in the motion vector switching area) as (n When the value divided by (the number of macroblocks existing in the period) becomes equal to or larger than a predetermined threshold value, the motion vector detection range is switched, and the switched motion vector detection range is set to the motion vector detection means 21 and the switching area determiner 14. To return.

For example, when the value obtained by dividing (the number of motion vectors existing in the area D) by (the number of macroblocks existing in n periods) is equal to or greater than a predetermined threshold, the motion vector detection range is calculated as shown in FIG. 5 (a) and 5 (b), from the motion vector detection range A3 to the motion vector detection range A
Switch to 4. That is, when the motion vector detection range is reduced, or when the value obtained by dividing (the number of motion vectors existing in the area U) by (the number of macroblocks existing in n periods) is equal to or greater than a predetermined threshold value, For example, as shown in FIGS. 6A and 6B, the motion vector detection range is changed from the motion vector detection range A3 to the motion vector detection range A2.
Switch to. That is, the motion vector detection range is expanded.

By adopting such a configuration, it is possible to improve the detection accuracy of the motion vector according to the motion of the input moving image and reduce the generated code amount.

Next, the flow of the series of processes described above will be described with reference to FIG. 9 while referring to the block diagram shown in FIG.

First, the input moving image video input from the input terminal 1 is rearranged in the decoding order by the frame rearranger 2, and is subdivided into N pieces (where N is a natural number of 2 or more) per frame in step 31. It becomes a converted macroblock moving image signal.

In step 32, the changeover switch 18 determines whether the macroblock moving image signal extracted from the frame rearranger 2 in the decoding order is an I picture or a non-I picture. When the changeover switch 18 determines that the macroblock moving image signal is an I picture, the switch 20 is turned on.
Set to FF state.

In step 33, the macroblock moving image signal determined to be the I picture is supplied to the DCT unit 3, the quantizer 4,
The decoded signal of the macroblock moving image of the I picture is stored in the frame memory 11 via the inverse quantizer 9, the inverse DCT device 10, and the adder 19.

Next, in step 34, it is judged that the compression / decoding of the macroblock moving image signal for one frame is completed, and when one frame is not reached, the process returns to step 32.

In step 32, it is judged whether the macroblock moving image signal extracted from the rearranger 2 is an I picture.
If it is not a picture, the changeover switch 18 determines in step 35 whether it is a P picture or a B picture.

When it is determined that the macroblock moving image signal is a P picture, the subtractor 17 subtracts the macroblock moving image signal and the predicted video signal output from the predictor 12 in step 36 to output a difference signal. At the same time, the switch 20 is turned on.

The difference signal subtracted in step 36 passes through the DCT unit 3, the quantizer 4, the inverse quantizer 9 and the inverse DCT unit 10 in step 37, and the adder 19 inverse DC of the P picture.
The T signal and the predicted video signal output from the predictor 12 (in this example, the predicted video signal is from the immediately preceding I picture, but when the P picture continues, the predicted video signal is from the immediately preceding P picture) And are added and the macroblock reference signal is stored in the frame memory 11 until one frame is formed. At the same time, the predictor 12 generates a predicted video signal using a motion vector that minimizes the difference between the frame reference signal and the macroblock moving image signal from the frame rearranger 2.

The predicted video signal generated in step 37 is
In step 38, the macroblock switching signal is input to the comparator 15, and the comparator 15 compares the predicted video signal with the motion vector switching area output from the switching area determiner 14 to output a macroblock switching signal to the counter 16. Counter 16
The macroblock switching signal is stored until one frame is reached.

Next, at step 34, it is judged that the compression / decoding of the macroblock moving image signal for one frame is completed, and if one frame is not reached, the process returns to step 32. In the above example, the step of turning on the switch 20 is set to step 36, but any step may be performed before addition is performed by the adder 19, and step 35 or step 37 may be performed. Of course.

In step 32, it is judged whether the macroblock moving image signal extracted from the rearranger 2 is an I picture,
If it is not an I picture, it is a P picture or B in step 35.
The changeover switch 18 determines whether the picture is a picture.

When it is determined that the macroblock moving image signal is a B picture, the subtractor 17 subtracts the macroblock moving image signal and the predicted video signal output from the comparator 12 in step 39 to output a difference signal. . The difference signal subtracted in step 39 is quantized by the DCT device 3 and the quantizer 4 in step 40, and in step 34,
The end of compression decoding of the macroblock moving image signal for one frame is judged, and when it has not reached one frame, the process returns to step 32.

If it is determined in step 34 that one frame has been reached, in step 41 the counter 16
To output a frame switching signal to the detection range determiner 13,
The detection range determiner 13 feeds back the motion vector detection range on a frame-by-frame basis to the predictor 12, and the switching region determiner 1
4, and the switching area determiner 14 generates a motion vector switching area and outputs it to the comparator 15.

In step 41, a motion vector detection range for each frame is generated and output to the predictor 12. Then, in step 42, the moving picture image signal ends and it is judged whether or not there is a next frame. Frame sorter 2
Then, if there is no next frame, the process ends.

In the above embodiment, the case where the motion vector detection range is updated in frame units has been described, but a predetermined group of input moving image signals such as screen units, frame units, group of pictures (GOP) units, etc. It can also be done in units. However, the motion vector detection range determiner 13 and the frame memory 11 are selected according to the unit of aggregation.
Etc. need to be changed.

Further, although the above embodiment has been described by taking MPEG compression as an example, the compression / decoding method is not limited to MPEG. 261 or H.261. Two
Any compression method, such as 63, that performs inter-frame prediction that reduces the redundancy in the time direction can be applied.

According to the present embodiment, even when there are a plurality of detection ranges for motion vector detection, when moving image compression coding is performed without increasing the hardware scale,
It has an effect that an optimum motion vector detection range can be selected according to the speed of movement of the input image, and as a result, an excellent effect that high image quality can be realized is obtained. Also,
It is possible to detect an appropriate motion vector even in an image with large motion, and set an appropriate motion vector detection range.

The program of the present invention is a program for causing a computer to execute all or part of the steps (or steps, operations, actions, etc.) of the above-described motion vector detection method of the present invention. , A program that operates in cooperation with a computer.

Further, the recording medium of the present invention causes a computer to execute all or part of all or some of the steps (or steps, operations, actions, etc.) of the above-described motion vector detecting method of the present invention. Is a recording medium carrying a program for executing the operation, which is readable by a computer and in which the read program cooperates with the computer to execute the operation.

The "partial means (or device, element, etc.)" of the present invention means one or some of the plural means, and the above-mentioned The "partial step (or process, operation, action, etc.)" means one or some of the plurality of steps.

The "function of the means (or device, element, etc.)" of the present invention means all or a part of the function of the above means, and the "step (or process, operation) of the present invention". ,
"Operation or the like" means an operation of all or a part of the steps.

Further, one usage form of the program of the present invention is:
It may be recorded in a computer-readable recording medium and operate in cooperation with the computer.

Further, one usage form of the program of the present invention is as follows:
Transmitted through a transmission medium, read by a computer,
It may be a mode of operating in cooperation with a computer.

Further, the data structure of the present invention includes a database, a data format, a data table, a data list, a data type and the like.

Further, the recording medium includes a ROM and the like, and the transmission medium includes the transmission medium such as the Internet,
Light, radio waves, sound waves, etc. are included.

The computer of the present invention described above is a C
The hardware is not limited to pure hardware such as PU, but may include firmware, OS, and peripheral devices.

As described above, the structure of the present invention is
It may be realized by software or hardware.

[0120]

As is apparent from the above description, according to the present invention, it is possible to detect a proper motion vector even in an image having a large motion, and to set a proper motion vector detection range. It is possible to provide a moving picture compression encoding device, a motion vector detecting method, a recording medium, and a program capable of performing the above.

[Brief description of drawings]

FIG. 1 is a block diagram of a moving image compression encoding apparatus according to a first embodiment of the present invention.

FIG. 2 is a diagram showing an example of a motion vector of a macroblock according to the first embodiment of the present invention.

FIG. 3 is a diagram showing an example of motion vectors and motion vector switching regions according to the first embodiment of the present invention.

FIG. 4A is a diagram showing motion vector detection range candidates in the first embodiment of the invention, and FIG. 4B is a diagram showing motion vector detection ranges in the first embodiment of the invention.

FIG. 5A is a diagram showing an example of a current motion vector detection range according to the first embodiment of the present invention. FIG. 5B is an example of an updated motion vector detection range according to the first embodiment of the present invention. Showing

FIG. 6A is a diagram showing an example of a current motion vector detection range in the first embodiment of the present invention. FIG. 6B is an example of an updated motion vector detection range in the first embodiment of the present invention. Showing

FIG. 7 is a diagram showing a timing of updating a motion vector detection range according to the first embodiment of the present invention.

FIG. 8A is a diagram showing an outline of pixel sampling when detecting a motion vector when the motion vector detection range is large according to the first embodiment of the present invention; and FIG. 8B is a first embodiment of the present invention. FIG. 6C is a diagram showing an outline of pixel sampling when detecting a motion vector in the case where the motion vector detection range in the first embodiment is medium (c) Motion in the case where the motion vector detection range is small in the first embodiment of the present invention Diagram showing the outline of pixel sampling when detecting a vector

FIG. 9 is a flowchart for determining a motion vector switching area according to the first embodiment of the present invention.

FIG. 10 is a block diagram showing a configuration of a conventional motion vector detection device.

FIG. 11 is a block diagram showing a configuration of a conventional moving image compression encoding apparatus.

FIG. 12 is an explanatory diagram showing an operation of a motion detection device 307A which constitutes a conventional moving image compression encoding device.

FIG. 13 is a CP constituting a conventional moving image compression encoding device.
Flowchart diagram showing the processing operation of U5

FIG. 14 is a diagram showing an example of a motion vector detection range and a motion vector of a conventional moving image compression encoding apparatus.

[Explanation of symbols]

1 input terminal 2 frame sorter 3 DCT device 4 Quantizer 5 Variable length encoder 6 buffer memory 7 output terminals 8 rate controller 9 Inverse quantizer 10 Inverse DCT device 11 frame memory 12 Predictor 13 Motion vector detection range determiner 14 Switching area determiner 15 Comparator 16 counter 17 Subtractor 18 Changeover switch 19 adder 20 switches 21 motion vector detecting means

   ─────────────────────────────────────────────────── ─── Continued front page    F term (reference) 5C059 KK19 MA00 MA23 MC11 ME01                       NN01 NN03 NN28 PP06 SS20                       UA02 UA33 UA39

Claims (14)

[Claims] 1. An input moving image video is provided in N frames per frame.
(Where N is a natural number of 2 or more), a macroblock generating unit that generates a macroblock moving image signal that has been subdivided into a plurality of pieces; A code decoding means for generating; a motion vector detecting means for detecting a motion vector within a first motion vector detection range from the decoded moving image signal and the macroblock moving image signal; Among them, a first outermost line which is the outermost line of the first motion vector detection range and a second outermost line which is the outermost line of the second motion vector detection range inside the first motion vector detection range. A motion vector counting means for counting the number of motion vectors existing between the outside line and the first motion vector, and the counted number of the first motion vectors. And a motion vector detection range determining means for expanding the first motion vector detection range on the basis of the first motion vector detection range. 2. The motion vector counting means counts the number of motion vectors within a third motion vector detection range inside the second motion vector detection range as the number of second motion vectors, 2. The moving picture compression coding apparatus according to claim 1, wherein the motion vector detection range determining means reduces the first motion vector detection range based on the counted number of the second motion vectors. 3. The motion vector detection range determination means,
If the number of counted first motion vectors is larger than a predetermined threshold value, the first motion vector detection range is expanded, and if it is smaller than the predetermined threshold value, the first motion vector detection range is not expanded. The moving picture compression coding apparatus according to claim 1, wherein the first motion vector detection range is not changed. 4. The motion vector detection range determination means,
The moving image compression encoding apparatus according to claim 1, wherein the larger the number of counted first motion vectors is, the larger the expansion rate of the first motion vector detection range is. 5. The motion vector detection range determining means is
The moving picture compression encoding apparatus according to claim 2, wherein the reduction ratio of the first motion vector detection range is increased as the number of counted second motion vectors increases. 6. The motion vector detection range determination means,
It has a plurality of types of motion vector detection ranges in advance, and a larger motion vector detection range is selected from the plurality of types of motion vector detection ranges as the number of counted first motion vectors increases, The moving picture compression coding apparatus according to claim 1, wherein the motion vector detection range is 1. 7. The motion vector detection range determining means is
It has a plurality of types of motion vector detection ranges in advance, and a smaller motion vector detection range is selected from the plurality of types of motion vector detection ranges as the number of counted second motion vectors increases, and 3. The moving picture compression coding apparatus according to claim 2, wherein the motion vector detection range is 1. 8. The motion vector detection range determination means,
The first motion vector detection range is updated for each P frame, or for each division unit obtained by dividing the P frame into n (where n ≦ N is a natural number), Is updated, the motion vector detection range determining means determines the number of the counted first motion vectors of the P frame or of the division unit as a macroblock existing in the P frame or in the division unit. The moving image compression encoding apparatus according to claim 1, wherein the first motion vector detection range is expanded when a number divided by the number of moving image signals is equal to or larger than a predetermined threshold value. 9. The motion vector detection range determination means,
The first motion vector detection range is updated for each P frame, or for each division unit obtained by dividing the P frame into n (where n ≦ N is a natural number), Is updated, the motion vector detection range determining means determines the number of the counted second motion vectors of the P frame or of the division unit as a macroblock existing in the P frame or in the division unit. The moving picture compression coding apparatus according to claim 1, wherein the first motion vector detection range is reduced when a number divided by the number of moving picture signals becomes equal to or larger than a predetermined threshold value. 10. The motion vector detection means, when expanding the first motion vector detection range, also expands the second motion vector detection range.
The moving image compression encoding apparatus according to any one of 6 and 8. 11. The motion vector detecting means, when reducing the first motion vector detection range, also reduces the third motion vector detection range.
The moving picture compression encoding device described. 12. The input moving image is N per frame.
(However, N is a natural number of 2 or more) is divided into a plurality of macroblock moving image signals, which are compressed and encoded, and then decoded to generate a decoded moving image signal and the macroblock moving image signal. A motion vector detecting step of detecting a motion vector within a first motion vector detection range; a first outermost line which is an outermost line of the first motion vector detection range among the detected motion vectors; A motion vector that counts the number of motion vectors between the second outermost line, which is the outermost line of the second motion vector detection range inside the first motion vector detection range, as the number of first motion vectors Counting step, a first outermost line which is the outermost line of the first motion vector detection range, and a second motion vector detection which is inside the first motion vector detection range A first motion, which is a second outermost line that is the outermost line of the enclosure and is the number of motion vectors on one or more second outermost lines adjacent to the first outermost line Motion vector detection including a motion vector counting step of counting the number of vectors, and a motion vector detection range determining step of expanding the first motion vector detection range based on the counted number of the first motion vectors. Method. 13. The motion vector detecting method according to claim 12, wherein N (where N
Is a natural number of 2 or more) and the first motion is generated from the decoded moving image signal generated by compressing and encoding the macroblock moving image signal generated by compression and the macroblock moving image signal. A motion vector detecting step of detecting a motion vector within a vector detection range; a first outermost line which is an outermost line of the first motion vector detection range among the detected motion vectors; and a first motion A motion vector counting step of counting, as the number of first motion vectors, the number of motion vectors between the second outermost line which is the outermost line of the second motion vector detection range inside the vector detection range; A motion vector detection range determining step of expanding the first motion vector detection range based on the counted number of the first motion vectors. Program to be executed by the data. 14. A recording medium carrying the program according to claim 13, which can be processed by a computer.