JP4213739B2 - Motion vector detection device - Google Patents

Description

  The present invention relates to a motion vector detection apparatus that detects a motion vector between frame images related to a previous frame and a subsequent frame that are in a time series relationship.

  As a conventional motion vector detection technique, as described in Patent Document 1, there is a method of detecting a motion vector by dividing an image into a plurality of blocks, detecting an edge for each block, and following the movement of the edge. is there. In this method, in order to reduce misjudgment when the spatial frequency is low and there is no characteristic pattern such as the sky, or when there are many feature points such as a lattice door, the spatial frequency is high. Weighting is performed by the number of edges per block, and reliability is evaluated. As a method for edge detection, a zero crossing method or the like is used.

Japanese Patent No. 3164121

  Although the motion vector detection method disclosed in Patent Document 1 reduces the erroneous determination by weighting the reliability of the motion vector calculated for each block by the number of edges for each block, real-time processing is required. In such a case, it is difficult to uniformly evaluate all blocks.

  That is, if the entire image is to be evaluated uniformly, it is necessary to perform the motion vector detection process after capturing the entire image, which is not suitable for real-time processing. In order to satisfy the processing time, it is necessary to complete the processing in units of blocks and proceed one after another. At this time, each block cannot be processed uniformly, so each block is uniformly edged. It is hard to say that sufficient results are obtained by weighting only by numbers.

  The present invention has been made to solve the above-described problems, and provides a motion vector detection device capable of evaluating the reliability of a motion vector calculated from each block while satisfying real-time processing. The purpose is to provide.

  The motion vector detection device according to claim 1 according to the present invention is a motion vector detection device for detecting a motion vector between frame images related to a previous frame and a rear frame that are in a time series relationship, and is a horizontal line. Edge enhancement means for emphasizing the edge in the vertical direction for each block divided into a plurality of blocks having a constant division width in the vertical direction with respect to a frame image read out by sequentially repeating pixel scanning in the vertical direction; Projecting means for projecting in the vertical direction for each block, and generating projection data having a data arrangement for one horizontal line in each of the blocks, with respect to the subsequent frame Maximum value obtaining means for obtaining a maximum value in the array element of the post-frame projection data obtained by the projecting means; A waveform obtained by graphing array element values in the order of elements of the data array with respect to the previous frame projection data obtained by the projecting means with respect to the previous frame intersects with a straight line where the array element value is a predetermined constant value. Specifying means for specifying the position of the array element at each intersection to output as intersection information, and extracting means for extracting a data array in a predetermined range centered on the position of the array element at each intersection from the post-frame projection data And for each data array in a predetermined range extracted by the extraction means, add values of array elements having the same relative position to the position of the array element at each intersection, and based on the obtained addition result, An adder for calculating a horizontal motion vector for each block, and a frame image based on the horizontal motion vector for each block calculated by the adder. Detecting means for detecting an entire horizontal motion vector, wherein the detecting means includes the maximum value of the post-frame projection data obtained by the maximum value obtaining means, the addition result obtained by the adding means, and The reliability of the horizontal motion vector for each block is evaluated using at least one of the intersection information obtained by the specifying means.

  The motion vector detection device according to claim 10 according to the present invention is a motion vector detection device for detecting a motion vector between frame images related to a preceding frame and a following frame which are in a time series front-rear relationship. Edge enhancement means for enhancing a horizontal edge for each block divided into a plurality of blocks having a constant division width in the horizontal direction with respect to a frame image read by sequentially repeating pixel scanning in the vertical direction; Projecting means for projecting in the horizontal direction for each block and generating projection data having a data arrangement for one vertical line in each of the blocks for the image whose edges are enhanced by the enhancing means, and for the subsequent frame Maximum value obtaining means for obtaining a maximum value in the array element of the post-frame projection data obtained by the projection means A waveform obtained by graphing array element values in the order of the elements of the data array with respect to the previous frame projection data obtained by the projecting means with respect to the previous frame intersects with a straight line where the array element value is a predetermined constant value. Specifying means for specifying the position of the array element at each intersection to output as intersection information, and extracting means for extracting a data array in a predetermined range centered on the position of the array element at each intersection from the post-frame projection data And for each data array in a predetermined range extracted by the extraction means, add values of array elements having the same relative position to the position of the array element at each intersection, and based on the obtained addition result, An adder that calculates a vertical motion vector for each block, and a frame based on the vertical motion vector for each block calculated by the adder. Detecting means for detecting a vertical motion vector of the entire image, wherein the detecting means is the maximum value of the post-frame projection data obtained by the maximum value obtaining means, and the addition result obtained by the adding means. Then, at least one of the intersection information obtained by the specifying means is used to evaluate the reliability of the vertical motion vector for each block.

  According to the motion vector detection apparatus of the first aspect of the present invention, the detection means obtains the maximum value of the post-frame projection data obtained by the maximum value acquisition means, the addition result obtained by the addition means, and the identification means. Since the reliability of the horizontal motion vector for each block is evaluated using at least one of the obtained intersection information, by excluding the horizontal motion vector obtained from the low-reliability block, as a result, It is possible to calculate the horizontal motion vector of the entire frame image with high reliability.

  According to the motion vector detecting device of the present invention, the detecting means obtains the maximum value of the post-frame projection data obtained by the maximum value obtaining means, the addition result obtained by the adding means and the specifying means. Since the reliability evaluation of the vertical motion vector for each block is performed using at least one of the obtained intersection information, by excluding the vertical motion vector obtained from the low-reliability block, as a result, It is possible to calculate the vertical motion vector of the entire frame image with high reliability.

<Embodiment 1>
<Configuration of motion vector detection device>
FIG. 1 is a block diagram showing a main configuration of a motion vector detection device 1 according to Embodiment 1 of the present invention.

  The motion vector detection device 1 detects, for example, an image motion vector that represents the motion of a subject in a screen in a moving image, and the motion between frame images related to a previous frame and a subsequent frame that are in a chronological order. A vector is detected. The motion vector detected by the motion vector detection device 1 is used for camera shake correction of the video camera. Note that the frame image input to the motion vector detection device 1 is read out by performing horizontal pixel scanning and vertical line scanning as shown in FIG.

  The motion vector detection device 1 includes an input terminal 11, a horizontal direction motion vector detection unit 2 and a vertical direction motion vector detection unit 4, and two output terminals 12 and 13. The functions of the horizontal motion vector detection unit 2 and the vertical motion vector detection unit 4 may be realized by software by, for example, a microprocessor, and most of the functions are realized by hardware (partly software). Anyway. Of course, it goes without saying that all functions may be realized by hardware.

  For example, image data such as image (moving image) data or a video signal acquired by an image sensor in a video camera is input to the input terminal 11. In the image data input to the input terminal 11, a horizontal motion vector is detected by the horizontal motion vector detection unit 2, and the detected horizontal motion vector is output from the output terminal 12.

  On the other hand, the vertical motion vector detector 4 detects a vertical motion vector for the image data input to the input terminal 11. The vertical motion vector detected by the vertical motion vector detection unit 4 is output from the output terminal 13.

  Below, the structure of the horizontal direction motion vector detection part 2 and the vertical direction motion vector detection part 4 is demonstrated in order.

FIG. 3 is a block diagram showing the main configuration of the horizontal motion vector detection unit 2.
The horizontal motion vector detection unit 2 includes an input terminal 20, a vertical image segmentation unit 21, a vertical edge extraction filtering unit 22, a vertical block projection unit 23, and a first vertical block projection data maximum value storage. A unit 24, a bit number reduction unit 25, and a first vertical block projection line memory 26. The horizontal motion vector detection unit 2 includes a second vertical block projection line memory 27, a second vertical block projection data maximum value storage unit 28, a first threshold intersection search unit 29, and a vertical direction. A block projection data reading unit 30, a vertical block horizontal motion vector calculating unit 31, a horizontal motion vector determining unit 32, and an output terminal 33 are provided. The function of each part of the horizontal motion vector detection unit 2 described above will be briefly described (specific operations will be described in detail later).

  The vertical image dividing unit 21 divides the frame image input to the input terminal 20 in the vertical direction and outputs a block divided in the vertical direction (hereinafter also referred to as “vertical block”).

  The vertical edge extraction filtering unit 22 performs a filtering process for performing edge extraction for each block divided by the vertical image dividing unit 21.

  The vertical block projection unit 23 projects the edge-enhanced vertical block output from the vertical edge extraction filtering unit 22 in the vertical direction and outputs projection data for each vertical block.

  The first vertical block projection data maximum value storage unit 24 stores the maximum absolute value in the vertical block projection data of the current frame output from the vertical block projection unit 23. The first vertical block projection data maximum value storage unit 24 is described later based on the maximum value of the projection data of the vertical block of the current frame (hereinafter also referred to as “first vertical block projection data”). A second threshold value is calculated.

  Based on the maximum value of the first vertical block projection data stored in the first vertical block projection data maximum value storage unit 24, the bit number reduction unit 25 uses the vertical direction output from the vertical block projection unit 23. Reduce the number of bits in the projection data of the block.

  The first vertical block projection line memory 26 stores the first vertical block projection data whose bit number has been reduced by the bit number reduction unit 25.

  The second vertical block projection line memory 27 converts the vertical block projection data sent from the first vertical block projection line memory 26 into the projection data of the vertical block of the previous frame (hereinafter referred to as “second vertical block projection data”). It is also saved as “direction block projection data”.

  The second vertical block projection data maximum value storage unit 28 uses the maximum value of the projection data of the vertical block output from the first vertical block projection data maximum value storage unit 24 as the second vertical block projection data. Save as the maximum value of direction block projection data. Further, the second vertical block projection data maximum value storage unit 28 calculates a first threshold, which will be described later, based on the maximum value of the second vertical block projection data.

  The first threshold value intersection search unit 29 calculates the waveform of the second vertical block projection data related to the previous frame stored in the second vertical block projection line memory 27 and the second vertical block projection data maximum value. A point where the first threshold value calculated by the storage unit 28 intersects is obtained, and information on this intersection (hereinafter also referred to as “first threshold value intersection”) is output.

  The vertical block projection data reading unit 30 has a first vertical direction within a predetermined range (motion vector detection range) before and after the first threshold intersection obtained by the first threshold intersection search unit 29. The block projection data is read from the first vertical block projection line memory 26.

  The vertical block horizontal motion vector calculation unit 31 uses the second threshold output from the first vertical block projection data maximum value storage unit 24 and reads the first block read by the vertical block projection data reading unit 30. Each vertical block projection data of 1 is converted into n-values (n is an integer of 2 or more) to reduce the number of bits, and the n-valued projection data is added for each distance from the first threshold intersection. .

  The horizontal motion vector determination unit 32 determines the horizontal motion vector of the image based on the output from the vertical block horizontal motion vector calculation unit 31. The horizontal motion vector of the image determined here is output from the output terminal 33. The horizontal motion vector determination unit 32 receives the maximum value of the first vertical block projection data and the first threshold value intersection search unit 29 stored in the first vertical block projection data maximum value storage unit 24. It is configured to receive information on the output first threshold value intersection and use it for processing to improve the reliability of the horizontal motion vector.

FIG. 4 is a block diagram showing a main configuration of the vertical block projection unit 23.
The vertical block projection unit 23 includes an input terminal 231, an adder 232 that performs data addition for each horizontal line, and a vertical projection temporary storage memory 233 as a buffer memory that sequentially stores data added by the adder 232. And an output terminal 234.

  The input terminal 231 receives an image in which vertical edges are emphasized by the vertical edge extraction filtering unit 22 for each vertical block. The image input to the input terminal 231 is projected in the vertical direction by the adder 232 and the vertical projection temporary storage memory 233 for each vertical block. Specifically, the adder 232 adds the data for one horizontal line of the vertical block and the data for one horizontal line read from the vertical projection temporary memory 233, and the addition result is the vertical projection temporary. It is returned again to the storage memory 233 and stored. When the addition of all the horizontal lines in the vertical block is completed by repeating such an addition operation, the addition data of all the horizontal lines, that is, the projection data in the vertical direction is output from the output terminal 234.

  FIG. 5 is a block diagram illustrating a main configuration of the vertical block horizontal motion vector calculation unit 31.

  The vertical block horizontal motion vector calculation unit 31 adds three input terminals 311 to 313, an n-value calculator 314, and the first vertical block projection data converted to n-value by the n-value generator 314. An adder 315 to be performed, a horizontal motion vector addition memory 316 as a buffer memory for sequentially storing data added by the adder 315, a peak detector 317, and output terminals 318 and 319 are provided.

  The first vertical block projection data output from the vertical block projection data reading unit 30 is input to the input terminal 311, and the first vertical block projection data maximum value storage unit 24 is input to the input terminal 312. The output second threshold value is input. In addition, the first threshold value intersection information output from the first threshold value intersection search unit 29 is input to the input terminal 313.

  The n-value converter 314 converts the first vertical block projection data input from the input terminal 311 into n-values (for example, ternarization) based on the second threshold value input from the input terminal 312.

  The adder 315 adds the first vertical block projection data n-valued by the n-value calculator 314 and the data read from the horizontal motion vector addition memory 316 around the first threshold intersection. Then, the addition result is stored in the horizontal motion vector addition memory 316 again. When the addition for all the first threshold intersections related to the vertical block is completed by repeating such an addition operation, the addition data related to the vertical block is output to the peak detector 317.

  The peak detector 317 detects a peak position (horizontal motion vector to be described later) and a peak value in the addition data output from the adder 315. The peak position detected by the peak detector 317 is input to the horizontal direction motion vector determination unit 32 via the output terminal 318, and the peak value is input to the horizontal direction motion vector determination unit 32 via the output terminal 319. It will be.

Next, the configuration of the vertical motion vector detection unit 4 will be described.
FIG. 6 is a block diagram showing a main configuration of the vertical motion vector detection unit 4.

  The vertical motion vector detection unit 4 includes an input terminal 40, a horizontal image segmentation unit 41, a horizontal edge extraction filtering unit 42, a horizontal block projection unit 43, and a first horizontal block projection line memory 44. The first horizontal block projection data maximum value storage unit 45 is provided. The vertical motion vector detection unit 4 includes a second horizontal block projection line memory 46, a second horizontal block projection data maximum value storage unit 47, a third threshold intersection search unit 48, and a horizontal direction. A block projection data reading unit 49, a horizontal block vertical motion vector calculation unit 50, a vertical motion vector determination unit 51, and an output terminal 52 are provided. The function of each part of the above-described vertical motion vector detection unit 4 will be briefly described (specific operations will be described in detail later).

  The horizontal image dividing unit 41 divides the frame image input to the input terminal 40 in the horizontal direction and outputs a block divided in the horizontal direction (hereinafter also referred to as “horizontal block”).

  The horizontal direction edge extraction filtering unit 42 performs a filtering process for performing edge extraction for each block divided by the horizontal direction image dividing unit 41.

  The horizontal block projection unit 43 projects the edge-emphasized horizontal block output from the horizontal edge extraction filtering unit 42 in the horizontal direction, and outputs projection data for each horizontal block.

  The first horizontal block projection line memory 44 converts the horizontal block projection data output from the horizontal block projection unit 43 into the horizontal block projection data of the current frame (hereinafter referred to as “first horizontal block projection data”). "Also called").

  The first horizontal block projection data maximum value storage unit 45 stores the maximum value of the horizontal block projection data of the current frame output from the horizontal block projection unit 43.

  The second horizontal block projection line memory 46 converts the horizontal block projection data sent from the first horizontal block projection line memory 44 into projection data (hereinafter referred to as “second horizontal block projection data” of the horizontal block of the previous frame). It is also saved as “direction block projection data”.

  The second horizontal block projection data maximum value storage unit 47 uses the maximum value of the horizontal block projection data output from the first horizontal block projection data maximum value storage unit 45 as the second horizontal block projection data maximum value for the previous frame. Save as the maximum value of direction block projection data. The second horizontal block projection data maximum value storage unit 47 calculates a third threshold value and a fourth threshold value, which will be described later, based on the maximum value of the second horizontal block projection data regarding the previous frame.

  The third threshold intersection search unit 48 includes a second horizontal block projection data related to the previous frame stored in the second horizontal block projection line memory 46, and a second horizontal block projection data maximum value storage unit. The point where the third threshold value calculated at 47 intersects is obtained, and information on this intersection (hereinafter also referred to as “third threshold value intersection”) is output.

  The horizontal block projection data reading unit 49 has a first horizontal direction within a predetermined range (motion vector detection range) before and after the third threshold intersection obtained by the third threshold intersection search unit 48. Block projection data is read from the first horizontal block projection line memory 44.

  The horizontal block vertical motion vector calculation unit 50 uses the fourth threshold value output from the second horizontal block projection data maximum value storage unit 47, and is read by the horizontal block projection data read unit 49. Each horizontal block projection data of 1 is converted into n-values (n is an integer of 2 or more) to reduce the number of bits, and the n-valued projection data is added for each distance from the third threshold intersection. .

  The vertical motion vector determination unit 51 determines the vertical motion vector of the image based on the output from the horizontal block vertical motion vector calculation unit 50. The vertical motion vector of the image determined here is output from the output terminal 52. Note that the vertical direction motion vector determination unit 51 receives the maximum value of the first horizontal block projection data stored in the first horizontal block projection data maximum value storage unit 45 and the third threshold value intersection search unit 48. It is configured to receive information on the output third threshold intersection and use it for processing to increase the reliability of the vertical motion vector.

FIG. 7 is a block diagram showing a main configuration of the horizontal block projection unit 43.
The horizontal block projection unit 43 includes an input terminal 431, an adder 432 for adding one horizontal line data of the horizontal block, and a horizontal projection temporary as a buffer memory for sequentially storing the data added by the adder 432. A storage memory 433 and an output terminal 434 are provided.

  The input terminal 431 receives an image in which horizontal edges are emphasized by the horizontal edge extraction filtering unit 42. The image input to the input terminal 431 is projected in the horizontal direction by the adder 432 and the horizontal projection temporary storage memory 433 for each horizontal block. Specifically, with respect to the pixels of one horizontal line in the horizontal block, the addition result that is added by the adder 432 and stored in the horizontal projection temporary storage memory 433 up to the previous pixel and the pixel input from the input terminal 431. Are added by the adder 432, and the addition result is returned to the horizontal projection temporary storage memory 433 and stored. When the addition of one horizontal line in the horizontal block is completed by repeating such an addition operation, the addition data of all the pixels in one horizontal line of the horizontal block, that is, the projection data in the horizontal direction is output from the output terminal 434. Will be. Thereafter, similarly, the projection data in the horizontal direction of the next horizontal block is processed, and when the processing of all the horizontal blocks for one horizontal line is completed, the processing of the next one horizontal line is performed.

  FIG. 8 is a block diagram showing a main configuration of the horizontal block vertical motion vector calculation unit 50.

  The horizontal block vertical motion vector calculation unit 50 adds three input terminals 501 to 503, an n-value converter 504, and the first horizontal block projection data converted to n-value by the n-value generator 504. An adder 505 to be performed, a vertical motion vector addition memory 506 as a buffer memory for sequentially storing data added by the adder 505, a peak detector 507, and output terminals 508 and 509 are provided.

  The first horizontal block projection data output from the horizontal block projection data reading unit 49 is input to the input terminal 501, and the second horizontal block projection data maximum value storage unit 47 is input to the input terminal 502. The output fourth threshold value is input. In addition, the information about the third threshold value intersection output from the third threshold value intersection search unit 48 is input to the input terminal 503.

  The n-value converter 504 converts the first horizontal block projection data input from the input terminal 501 into n-values (for example, ternarization) based on the fourth threshold value input from the input terminal 502.

  The adder 505 adds the first horizontal block projection data converted to the n-value by the n-value generator 504 and the data read from the vertical motion vector addition memory 506 around the third threshold value intersection. Then, the addition result is stored in the vertical motion vector addition memory 506 again. When the addition for all the third threshold intersections regarding the horizontal block is completed by repeating such an addition operation, the addition data regarding the horizontal block is output to the peak detector 507.

  The peak detector 507 detects a peak position (vertical motion vector to be described later) and a peak value in the addition data output from the adder 505. The peak position detected by the peak detector 507 is input to the vertical direction motion vector determination unit 51 via the output terminal 508, and the peak value is input to the horizontal direction motion vector determination unit 32 via the output terminal 509. It will be.

  The operation of the motion vector detection apparatus 1 having the above configuration will be described below.

<Operation of Motion Vector Detection Device 1>
<Operation of Horizontal Motion Vector Detection Unit 2>
First, the operation of the horizontal motion vector detection unit 2 that detects the horizontal motion vector of an image in the motion vector detection device 1 will be described.

  As shown in FIG. 2, when a frame image read out by sequentially repeating pixel scanning of the horizontal line in the vertical direction is input to the input terminal 20 of the horizontal direction motion vector detecting unit 2 shown in FIG. 21 is divided into blocks in the vertical direction. That is, in the vertical image dividing unit 21, a plurality of image regions (vertical blocks) obtained by dividing the frame image in the vertical direction are set. As a result, in the subsequent processing, processing and management are performed for each vertical block.

  In the vertical image division unit 21, for example, as shown in FIG. 9A, image data of 640 pixels × 480 pixels is converted into seven vertical blocks vb0 to vb0 having a width of 64 pixels (division width) in the vertical direction. Divided into vb6. Although the image data vb7 at the lowest stage in the vertical direction is not used in the detection of the horizontal motion vector, the seven vertical blocks vb0 to vb6 occupying most of the frame image are used for the detection of the horizontal motion vector. Therefore, it is considered that there is no particular problem in terms of detection accuracy. Here, it is not essential to set the division width and the number of divisions shown in FIG.

  The image divided by the vertical image dividing unit 21 into seven vertical blocks vb0 to vb6 as shown in FIG. 9A is extracted, in other words, edge components extending in the vertical direction by the vertical edge extraction filtering unit 22. For example, a filtering process for emphasizing an image portion that changes sharply in the horizontal direction is performed.

  As a filter used in this filtering processing, a (1, -1,) 2-tap filter that simply takes a difference from a pixel adjacent in the horizontal direction, or (-1, 2, -1) corresponding to a second order differential. It is possible to use a 3-tap filter. Note that it is not essential to use such a filter, and any filter may be used as long as the output value increases in an image portion where the luminance change in the horizontal direction increases.

  The image data in which the vertical edge is emphasized for each of the vertical blocks (image regions) vb0 to vb6 by the vertical edge extraction filtering unit 22 is input to the vertical block projection unit 23, and the vertical block projection unit 23 Projected vertically. This projection can reduce the noise component in the vertical direction (between lines) and can enhance the edge component in the vertical direction, so that the vertical edge corresponding to the feature point can be emphasized to improve the motion vector detection accuracy. It will be. The operation of the vertical block projection unit 23 will be described with reference to the conceptual diagram of FIG.

  In the vertical block projection unit 23, when the input of the vertical blocks vb0 to vb6 shown in FIG. 9A is completed, that is, the final pixels of the final line in the vertical blocks vb0 to vb6 with edge enhancement are input. At this point, all array elements of the vertical direction block projection data vn0 to vn6 (FIG. 9B) having the data array Mv for one horizontal line are generated. The data array Mv has array elements of the total number of pixels on the horizontal line (for example, 640). However, in a 2-tap filter such as (1, -1), the effective element is the total number of pixels of the horizontal line − In a 3-tap filter such as 1 (for example, 639) and (−1, 2, −1), the effective elements are the total number of pixels in the horizontal line−2 (for example, 638).

  Specifically, as shown in FIG. 4, the image data of the vertical blocks vb0 to vb6 (image data subjected to vertical edge emphasis) input via the input terminal 231 are sequentially added to the adder 232. Is input.

  In the adder 232, first, the first horizontal line of the input vertical block is written into the vertical projection temporary storage memory 233 without reading the data in the vertical projection temporary storage memory 233. Next, the adder 232 reads the addition result up to the previous line stored in the vertical projection temporary storage memory 233, performs addition with the horizontal one line of the vertical block input from the input terminal 231, and The addition result is written back to the vertical projection temporary storage memory 233.

  When the final horizontal line in the vertical block is input to the adder 232, the addition result up to the previous line stored in the vertical projection temporary storage memory 233 is read and the vertical block input from the input terminal 231 is read. And the addition result, that is, the data obtained by adding all the horizontal lines of the vertical block is used as projection data of the vertical block, and the first vertical block projection data maximum from the output terminal 234 is obtained. The data is output to the value storage unit 24 and the bit number reduction unit 25.

  The adder 232 temporarily stores the projection data obtained by adding all the horizontal lines of the vertical block in the vertical projection temporary storage memory 233, and when the first line of the next vertical block is input, the vertical projection is performed. The projection data in the temporary storage memory 233 may be read and output from the output terminal 234.

  The first vertical block projection data maximum value storage unit 24 calculates the maximum value related to the projection data of the vertical block output from the vertical block projection unit 23 and stores it as the vertical block projection data maximum value of the current frame. To do. That is, the first vertical block projection data maximum value storage unit 24 obtains the maximum value in the array element of the data array Mv (FIG. 9B) relating to the projection data of the current frame (subsequent frame), and calculates this maximum value. Remember.

  Further, the first vertical block projection data maximum value storage unit 24 calculates the second threshold value based on the calculated vertical block projection data maximum value of the current frame. For example, if the maximum value regarding the projection data of the vertical block of the current frame is P1max, the second threshold value α2 is calculated by the following equation (1).

  α2 = P1max × k1 (1)

  Here, k1 is a predetermined coefficient, and 0 <k1 <1.

  Note that the calculation of the second threshold value α2 is not limited to the above equation (1), and it is sufficient that the second threshold value α2 increases as the vertical block projection data maximum value P1max of the current frame increases. Alternatively, a conversion table may be used.

  The bit number reduction unit 25 determines the effective bit range of the projection data based on the maximum value of the vertical block projection data of the current frame input from the first vertical block projection data maximum value storage unit 24. Then, the upper invalid bit and the lower invalid bit set based on the valid bit range are reduced from the vertical block projection data input from the vertical block projection unit 23, and the vertical direction of the current frame configured only by the valid bits The block projection data is output to the first vertical block projection line memory 26.

  The first vertical block projection line memory 26 stores the vertical block projection data of the current frame whose number of bits has been reduced by the bit number reduction unit 25 for each vertical block as first vertical block projection data. . That is, the first vertical block projection line memory 26 stores the number of bits (each array in the bit number reduction unit 25 based on the maximum value of the projection data obtained by the first vertical block projection data maximum value storage unit 24. Projection data of the current frame (subsequent frame) in which the element data length) is reduced is stored.

  The first vertical block projection line memory 26 reads the vertical block projection data of the previous frame at a timing when new first vertical block projection data relating to the current frame is input, and the second vertical block projection This is given to the line memory 27. The second vertical block projection line memory 27 stores the vertical block projection data of the previous frame read from the first vertical block projection line memory 26 as second vertical block projection data.

  Similarly, the first vertical block projection data maximum value storage unit 24 receives the vertical block projection data of the previous frame at the timing when the new maximum value of the first vertical block projection data for the current frame is input. The maximum value is read out and given to the second vertical block projection data maximum value storage unit 28. In the second vertical block projection data maximum value storage unit 28, the maximum value of the vertical block projection data of the previous frame read from the first vertical block projection data maximum value storage unit 24 is the first value related to the previous frame. 2 is stored as the maximum value of the vertical block projection data.

  In other words, the maximum value of the vertical block projection data of the current frame stored in the first vertical block projection data maximum value storage unit 24 is the second vertical block projection data maximum value of the next frame. This is stored in the unit 28 as the maximum value of the vertical block projection data of the previous frame.

  The second vertical block projection data maximum value storage unit 28 sets a first threshold value (predetermined constant value) based on the maximum value of the second vertical block projection data regarding the previous frame. For example, assuming that the maximum value of the vertical block projection data of the previous frame is P2max, the first threshold value α1 is calculated by the following equation (2).

  α1 = P2max × k2 (2)

  Here, k2 is a predetermined coefficient, and 0 <k2 <1.

  Note that the calculation of the first threshold value α1 is not limited to the above equation (2), and it is sufficient if the first threshold value α1 increases as the vertical block projection data maximum value P2max of the previous frame increases. Alternatively, a conversion table may be used.

  The first threshold intersection search unit 29 outputs the second vertical block projection data read from the second vertical block projection line memory 27 and the second vertical block projection data maximum value storage unit 28. An intersection with the first threshold value (first threshold value intersection) is searched in the horizontal direction. The information on the first threshold intersection obtained by the first threshold intersection searching unit 29 is output to the vertical block projection data reading unit 30 and the vertical block horizontal motion vector calculating unit 31.

  The vertical block projection data read unit 30 outputs the (first) vertical block projection of the current frame corresponding to the motion vector detection range centered on the first threshold intersection output from the first threshold intersection search unit 29. Data is read from the first vertical block projection line memory 26. That is, the first threshold intersection is A (i) (where i = 1, 2,... P, p is the total number of detected first threshold intersections), and the motion vector detection range is the first threshold. Assuming the range from (−V) to (+ V) (where V is a positive integer) centered on the intersection, the projection data read from the first vertical block projection line memory 26 is (A (i ) −V) to (A (i) + V), which is partial data of the first vertical block projection data.

  The first vertical block projection data read from the first vertical block projection line memory 26 by the vertical block projection data reading unit 30 is output to the vertical block horizontal motion vector calculation unit 31.

  The first vertical block projection data output from the vertical block projection data reading unit 30 is input to the n-value converter 314 via the input terminal 311 of the vertical block horizontal motion vector calculation unit 31 shown in FIG. Is done. The n-value converter 314 outputs the first vertical block projection data based on the second threshold value output from the first vertical block projection data maximum value storage unit 24 and input via the input terminal 312. n-valued. In other words, the n-value converter 314 converts the data length of each array element related to the projection data of the current frame extracted by the vertical block projection data reading unit 30 to the data length of each array element, for example, a ternization process. And compress. The processing of the n-value converter 314 will be described with reference to FIG.

  FIG. 10 is a diagram for explaining the n-value conversion processing in the n-value conversion device 314. Note that FIG. 10 shows an example of the ternary processing where n = 3.

  If the first vertical block projection data input to the n-value converter 314 is D, and the second threshold value input via the input terminal 312 is α2 (α2 is a positive integer), the n-value generator 314 Then, when D <(− α2), (−1) is output, when (−α2) ≦ D ≦ α2, 0 is output, and when D> α2, 1 is output. Done. That is, in the ternarization process in the n-valued unit 314, regarding the second threshold value α2 (α2> 0) set based on the maximum value of the array element of the data array Mv in the projection data of the current frame (subsequent frame), 3 when the value of the array element relating to the projection data of the current frame extracted by the vertical block projection data reading unit 30 is smaller than (−α2), (−α2) or more and α2 or less, and 3 Trinization is performed in stages.

  With regard to the n-value conversion processing by the n-value generator 314, the partial waveform of the first vertical block projection data of the current frame output from the vertical block projection data reading unit 30 is compared with the first threshold intersection. Therefore, it is important to ensure bit accuracy that can identify peaks and valleys in the waveform of the first vertical block projection data. It is.

  On the other hand, when the value of the first vertical block projection data output from the vertical block projection data reading unit 30 is adopted without reducing the number of bits in the n-value converter 314, the first There is a possibility that a small amplitude peak or valley corresponding to the vertical block projection data D> α2 or a small amplitude peak corresponding to D <(− α2) or a small amplitude peak corresponding to D <(− α2) may be buried. There is inappropriate. Furthermore, since the small peaks and valleys corresponding to (−α2) ≦ D ≦ α2 are easily affected by noise and have a large number, the peaks and valleys having an appropriate amplitude in which the characteristics of the image appear are buried.

  Therefore, the n-value generator 314 improves the motion vector detection accuracy by performing an appropriate n-value process on the first vertical block projection data.

  The operations of the first threshold intersection searching unit 29, the vertical block projection data reading unit 30, and the vertical block horizontal motion vector calculating unit 31 described above are shown in FIGS. 11 (a), 11 (b), and 11. This will be specifically described with reference to (c). Note that the horizontal axes of FIGS. 11A and 11B indicate the positions of the array elements of the projection data array Mv (FIG. 9B). In FIG. 11A, each of the first threshold intersections A (1) to A (8) is indicated by a circle.

  The first threshold value intersection search unit 29 outputs the second vertical block projection data maximum value storage unit 28 in the waveform of the second vertical block projection data W2 for the previous frame as shown in FIG. First threshold value intersections A (1) to A (8) that intersect the first threshold value α1 thus obtained are obtained. That is, the first threshold value intersection search unit 29 relates to the projection data obtained by the vertical block projection unit 23 with respect to the previous frame, and the array element values in the order of the elements in the projection data array Mv (FIG. 9B). The position of the array element at each first threshold value intersection where the waveform W2 in which the value of the array element intersects the straight line where the value of the array element is the first threshold value (predetermined constant value) α1 is specified.

  Next, the vertical block projection data reading unit 30 performs the first vertical detection for a predetermined motion vector detection range centered on each of the first threshold intersections A (1) to A (8) shown in FIG. The vertical block projection data of the current frame is read from the direction block projection line memory 26. That is, the vertical block projection data reading unit 30 outputs from the vertical block projection unit 23 a data array in a predetermined range centered on the position of the array element of the projection data (data array) at each first threshold intersection. Extracted from the projection data of the current frame (subsequent frame) whose bit number has been reduced by the bit number reduction unit 25. For example, for the first threshold value intersection A (7), as shown in FIG. 11B, the first threshold value intersection A (7) is centered on (A (7) -V) to (A (7) + V). The first vertical block projection data W1 corresponding to the range up to (the waveform portion within the rectangular broken line) is read out.

  Then, the first vertical block projection data read by the vertical block projection data reading unit 30 uses the second threshold value α2 output from the first vertical block projection data maximum value storage unit 24. The n-value unit 314 of the vertical block horizontal direction motion vector calculation unit 31 performs n-value processing. For example, for the first threshold intersection A (7), the first threshold is based on the magnitude relationship of the first vertical block projection data W1 with respect to the second threshold α2 and (−α2) shown in FIG. With respect to the range from (A (7) −V) to (A (7) + V) centering on the intersection A (7) (the waveform portion in the rectangular broken line), the first vertical as shown in FIG. The direction block projection data is ternarized. As a result, the vertical block projection data of the current frame is represented by “−1”, “0”, or “1”.

  In the n-value converter 314, n-value conversion processing as shown in FIG. 11C is performed on all the first threshold value intersections output from the first threshold value intersection search unit 29.

  Next, in the adder 315 (FIG. 5), the n-value generator 314 converts the n-value into the n-value centering on the first threshold-value intersection output from the first threshold-value intersection search unit 29 via the input terminal 313. The first vertical block projection data is added to the addition value of the first n-valued first vertical block projection data read from the horizontal motion vector addition memory 316 and added. The result is stored again in the horizontal motion vector addition memory 316. Then, the adder 315 adds the n-valued first vertical block projection data relating to the last one of all the first threshold intersections detected by the first threshold intersection search unit 29 to obtain one When the addition process for the vertical block is terminated, the addition result is output to the peak detector 317. In addition, after the addition process in the adder 315 is completed, the peak detection unit 317 may read the addition result from the horizontal motion vector addition memory 316 that stores the addition results regarding all the first threshold intersections. good.

  The peak detector 317 includes all the first threshold intersections detected by the first threshold intersection search unit 29 in a motion vector detection range (the above-described ± V range) centered on each first threshold intersection. Data obtained by adding the corresponding n-valued first vertical block projection data (hereinafter also referred to as “vertical block n-valued data”) is input. The value is detected by peak detector 317. The peak position of the vertical block n-valued data detected by the peak detector 317 becomes a horizontal motion vector obtained from the vertical block, and is output to the horizontal motion determination unit 32 via the output terminal 318. . Similarly, the peak value at that time is output from the output terminal 319.

  The operations of the adder 315 and the peak detector 317 described above will be specifically described with reference to FIGS. 12 (a) and 12 (b). In FIG. 12A, in the motion vector detection range (± V range) centering on the first threshold intersections A (1) to A (8) shown in FIG. The block projection data is conceptually shown as three values.

  In the adder 315, when ternary data around the first threshold intersections A (1) to A (8) shown in FIG. 12 (a) are sequentially input, these data are added, and FIG. Vertical block n-valued data as shown in b) is generated. Specifically, in the adder 315, the vertical block projection data reading unit 30 extracts the vertical block projection data (data array Mv (FIG. 9B)) and the n-value unit 314 compresses the data length. For each data array of the motion vector detection range (predetermined range) related to the frame, values of array elements having the same relative position with respect to the position of the array element at each first threshold intersection are added.

  When the vertical block n-valued data generated by the adder 315 is input to the peak detector 317, the horizontal peak position hv shown in FIG. 12B is detected as the horizontal motion vector of the vertical block. Is done. That is, the peak detector 317 detects a motion vector in the horizontal direction of the frame image based on the addition result added by the adder 315.

  In principle, the peak detector 317 searches for a peak position having the maximum value in the motion vector detection range (± V range). If there are a plurality of the same maximum values, the peak detector 317 is close to the origin 0 ( If the distance to the origin 0 is the same, the negative position) is given priority. It should be noted that the maximum value at the positive position may be prioritized without being limited to such a peak position detection rule, and the tendency of the motion vector in the previous frame is used for detection of the peak position in the current frame. Also good.

  The horizontal motion vector (peak position) calculated for each vertical block by the peak detector 317 and the peak value of the added data obtained by adding the n-valued vertical block (hereinafter referred to as “vertical block n-valued addition”). The data peak value ”is also input to the horizontal direction motion vector determination unit 32 via the output terminals 318 and 319, respectively, and the vertical block n-valued addition data peak value is used to determine whether the vertical block is valid / invalid. used.

  In the horizontal direction motion vector determination unit 32, the horizontal direction motion vector of the entire image is determined based on the horizontal direction motion vector of each vertical direction block sequentially output from the vertical direction block horizontal direction motion vector calculation unit 31.

  At this time, the maximum value of the first vertical block projection data output from the first vertical block projection data maximum value storage unit 24, the vertical block n output from the vertical block horizontal motion vector calculation unit 31 The validity / invalidity of each vertical block is determined based on the value-added data peak value and the information on the first threshold intersection output from the first threshold intersection search means 29. The horizontal motion vector calculated from the vertical block determined as an invalid block is not used when determining the horizontal motion vector of the entire image.

<Verification / invalidation judgment of vertical block>
<When using the maximum value of the first vertical block projection data>
Hereinafter, a method for determining validity / invalidity of each vertical block will be described.
FIG. 13 is a diagram illustrating a method for determining validity / invalidity of each vertical block using the maximum value of the first vertical block projection data.

  In FIG. 13, the image data of 640 pixels × 480 pixels shown in FIG. 9A is taken as an example, and seven vertical blocks vb0 to vb6 having a width of 64 pixels (divided width) in the vertical direction are arranged. This shows the case of division.

  In FIG. 13, the maximum value of the first vertical block projection data of each vertical block output from the first vertical block projection data maximum value storage unit 24 (FIG. 3) is set for each block. It is shown in hexadecimal notation.

  The horizontal direction motion vector determination unit 32 obtains the maximum value in all the blocks from the maximum value of the first vertical direction block projection data in each of the vertical direction blocks vb0 to vb6. In the example of FIG. 13, the vertical block vb2 has the maximum value in all blocks, and this value is referred to as the total vertical block projection data maximum value.

  Further, the horizontal direction motion vector determination unit 32 determines, for example, a vertical block having a maximum value of 1/4 or less as an invalid block with respect to the maximum value of all vertical block projection data. In the example of FIG. 13, the vertical blocks vb0, vb1, and vb6 are determined to be invalid blocks.

FIG. 14 is a diagram schematically illustrating determination of validity / invalidity of a vertical block.
FIG. 14 shows a graph in which the horizontal axis is the maximum value of all vertical block projection data and the vertical axis is the first vertical block projection data maximum value, and the slope is 1/4 (S = 1/4) is divided into valid blocks and invalid blocks.

  A vertical block that is determined to be an invalid block can be said to have a small feature (there are few clear parts) or a very fine design, and as a result, it can be trusted with respect to other valid blocks. It can be judged that the nature is low. Therefore, the reliability of the horizontal motion vector can be improved by not using the vertical block determined to be an invalid block for determining the horizontal motion vector of the entire image.

In the above description, the valid / invalid determination condition is described as being ¼ or less of the maximum value of all vertical block projection data. However, the present invention is not limited to this, and may be ½ or less or 1 / It may be 8 or less. In this way, by setting with the determination condition 1/2 ⁿ , it is possible to easily determine whether it is valid or invalid.

<When using vertical direction block n-valued addition data peak value>
FIG. 15 is a diagram for explaining a method of determining validity / invalidity of each vertical block using the vertical block n-valued addition data peak value.

  In FIG. 15, the image data of 640 pixels × 480 pixels shown in FIG. 9A is taken as an example, and seven vertical blocks vb0 to vb6 having a width of 64 pixels (divided width) in the vertical direction. This shows the case of division.

  In FIG. 15, the vertical block n-valued addition data peak value of each vertical block output from the vertical block horizontal motion vector calculation unit 31 (FIG. 3) is expressed in hexadecimal notation for each block. Show.

  The horizontal direction motion vector determination unit 32 obtains the maximum value from the vertical direction block n-valued addition data peak values in the vertical direction blocks vb0 to vb6. In the example of FIG. 15, the vertical block vb4 has the maximum value, and this value is referred to as the maximum value of the vertical block n-valued addition data peak value.

  Further, in the horizontal direction motion vector determination unit 32, when the maximum value of the vertical direction block n-valued addition data peak value is equal to or greater than a predetermined value A (for example, 12 in decimal notation), the vertical direction block n-valued addition data is A vertical block having a predetermined value B (for example, 7 in decimal notation) or less is determined as an invalid block. In the example of FIG. 15, the vertical blocks vb0, vb1, vb5, and vb6 are determined as invalid blocks.

  The output of the adder 315 (FIG. 5) of the vertical block horizontal direction motion vector calculation unit 31 (FIG. 3) is the first vertical direction centered on the first threshold intersection and n-valued with the second threshold. This is the sum of block projection data. The larger the number of first threshold intersections and the larger the amplitude (mountain) exceeding the second threshold (α2) on the plus side, the larger the value. On the contrary, if there is an amplitude exceeding the second threshold (−α2) on the minus side, it is canceled out.

  In other words, the maximum value of the output of the adder 315, that is, the vertical block n-valued addition data peak value of a certain vertical block is equal to or greater than the predetermined value A, while the vertical blocks of other vertical blocks When the n-valued addition data peak value is equal to or less than the predetermined value B, it can be said that the other vertical block is a picture whose addition result is canceled or a picture with few features and small amplitude.

  Accordingly, it can be determined that a block whose vertical block n-valued sum data peak value is less than or equal to the predetermined value B is less reliable than a block having the predetermined value A or more. It can be judged that the reliability is low. Therefore, the reliability of the horizontal motion vector can be improved by not using the vertical block determined to be an invalid block for determining the horizontal motion vector of the entire image.

FIG. 16 is a diagram schematically illustrating determination of validity / invalidity of a vertical block.
FIG. 16 shows a graph in which the horizontal axis represents the maximum value of the vertical block n-valued addition data peak value, and the vertical axis represents the vertical block n-value addition data peak value. When the maximum value of the added data peak value is equal to or greater than the predetermined value A, an operation is illustrated in which a vertical block whose vertical block n-valued added data is equal to or smaller than the predetermined value B is determined as an invalid block.

  In FIG. 16, when the maximum value of the vertical block n-valued addition data peak value is smaller than the predetermined value A, there is a block whose vertical block n-valued addition data peak value is equal to or less than the predetermined value B. Even so, the operation of not determining that the block is an invalid block is also shown.

  For example, taking FIG. 15 as an example, if the maximum value of the vertical block n-valued addition data peak value is 7, the vertical blocks vb0, vb1, vb5, and vb6 are not determined to be invalid blocks. This is because it cannot be said that the reliability of the block whose vertical block n-valued addition data peak value is the maximum is relatively low.

  In the above description, an example in which the valid / invalid determination condition is set to 12 for the predetermined value A and 7 for the predetermined value B is not limited to this, and the number of pixels in the horizontal direction of the image is not limited thereto. For example, when the number of pixels in the horizontal direction is 640 pixels, the predetermined value A may be set to a value of about 10, and the predetermined value B may be set to a value around half of that.

<When using the number of first threshold intersections>
FIG. 17 is a diagram illustrating a method for determining validity / invalidity of each vertical block using the number of first threshold intersections.

  In FIG. 17, the image data of 640 pixels × 480 pixels shown in FIG. 9A is taken as an example, and seven vertical blocks vb0 to vb6 having a width of 64 pixels (divided width) in the vertical direction. This shows the case of division.

  In FIG. 17, the number of first threshold intersections output from the first threshold intersection searching unit 29 (FIG. 3) is shown in hexadecimal notation for each block.

  In the first threshold intersection searching unit 29, the waveform of the second vertical block projection data relating to the previous frame stored in the second vertical block projection line memory 27 and the second vertical block projection data maximum value are stored. Information on the first threshold value intersection at which the first threshold value calculated by the storage unit 28 intersects is output. This information also includes information on the number of first threshold value intersections, as shown in FIG. As shown, the number of first threshold intersections is obtained for each vertical block vb0-vb6.

FIG. 18 is a diagram schematically illustrating determination of validity / invalidity of a vertical block.
FIG. 18 shows a graph in which the horizontal axis represents the maximum number of first threshold intersections in each of the vertical blocks vb0 to vb6, and the vertical axis represents the number of first threshold intersections. In the determination unit 32, the maximum value of the number of first threshold intersections for blocks in which the number of first threshold intersections in each of the vertical blocks vb0 to vb6 is equal to or less than a predetermined value D (for example, 3 in decimal notation). Regardless of whether it is an invalid block. In the example of FIG. 17, the vertical blocks vb0 and vb6 are determined as invalid blocks.

  The reliability of the horizontal motion vector can be improved by not using the vertical block determined to be an invalid block for determining the horizontal motion vector of the entire image.

  On the other hand, the number of first threshold intersections is at least equal to or less than the number of pixels in the horizontal direction. If the number is too large compared to the number of pixels in the horizontal direction, it can be said that a very periodic pattern is captured. For example, when the value is equal to or greater than a predetermined value E (for example, more than half the number of pixels in the horizontal direction), the block may be determined to be an invalid block.

  Further, as shown in FIG. 19, only when the maximum value of the number of first threshold intersections is equal to or greater than a predetermined value C (> D), a block having a predetermined value D or less is determined to be an invalid block. You may do it. In this case, if the maximum value of the number of first threshold intersections is smaller than the predetermined value C, even if there is a block having a predetermined value D or less, the block is not determined to be an invalid block, and the invalid block Can be set more finely.

  In the above description, an example in which the valid / invalid determination condition is that the predetermined value D is 3 and the predetermined value E is half the number of pixels in the horizontal direction is not limited to this.

  The method of determining validity / invalidity of each vertical block using the maximum value of the first vertical block projection data described above, and the validity / invalidity of each vertical block using the vertical block n-valued addition data peak value An invalid block is determined by using a method for determining invalidity and a method for determining validity / invalidity of each vertical block using information on the first threshold intersection, and is calculated from the vertical block that is determined as an invalid block. The reliability of the motion vector can be increased by not using the horizontal motion vector when determining the horizontal motion vector of the entire image.

  Further, the above-described three determination methods may be used alone or in combination.

  For example, the validity / invalidity is determined using the maximum value of the first vertical block projection data, and the validity / invalidity of each vertical block is determined using the vertical block n-valued addition data peak value. The validity / invalidity may be determined using the maximum value of the first vertical block projection data, and the validity / invalidity of each vertical block may be determined using the first threshold intersection information.

  With such a combination, an invalid block can be reliably selected, and the reliability of the motion vector can be further improved.

<Method for determining horizontal motion vector>
The horizontal direction motion vector determination unit 32 determines whether the vertical direction block is valid or invalid as described above, and determines the horizontal direction motion vector of the entire image from the horizontal direction motion vector for the vertical direction block determined to be a valid block. To do.

  At this time, vertical blocks having the same horizontal motion vector are collected to create a histogram.

  Hereinafter, an example of a method of determining the horizontal motion vector of the entire image will be described with reference to FIGS. 20 and 21. FIG.

  20 and 21 show a case where the detection range of the horizontal motion vector is −V to V. Here, as an example, a case where V is 31 is shown, and one vector from −31 to 31 is shown. Displayed at intervals. The numbers displayed in the boxes provided corresponding to the vectors represent the number of vertical blocks having the same vector.

  As shown in FIG. 20, among the horizontal direction motion vectors calculated for each vertical direction block, the horizontal direction motion vector 6 is calculated by two vertical direction blocks, but all other vertical direction blocks are disjoint. It is a horizontal motion vector, the minimum value of the distribution range is −14, and the maximum value is 27, and the difference 41 is very different from the motion vector detection range. In FIG. 20, the sand corresponding to the block corresponding to the horizontal motion vector obtained from each vertical block of the current frame is hatched.

  In the horizontal direction motion vector determination unit 32, when the difference between the maximum value and the minimum value of the distribution range of the horizontal direction motion vector obtained from each vertical block is equal to or greater than a predetermined threshold B (for example, V described above), The horizontal motion vector obtained from the vertical block has low reliability, and the horizontal motion vector is set to zero.

  By performing such processing, the reliability of the horizontal motion vector of the entire image can be increased.

  On the other hand, when the number of vertical blocks having the horizontal motion vector 6 is equal to or greater than a predetermined numerical value A (for example, 3), it is determined that the horizontal motion vector obtained from each vertical block is sufficiently reliable.

  Similarly, when the difference between the maximum and minimum horizontal motion vectors obtained from each vertical block is smaller than the threshold value B, the horizontal motion vector obtained from each vertical block is determined to be sufficiently reliable. To do.

  Note that the numerical value A and the threshold value B are not limited to the values described above. Further, the determination of the variation is not limited to the above-described difference between the maximum value and the minimum value of the horizontal motion vector, and the standard deviation is used. For example, when the standard deviation is greater than or equal to the threshold B, the variation is large. You may judge.

  As a result of the above-described processing, when it can be determined that the horizontal motion vector obtained from each vertical block is sufficiently reliable, the horizontal motion vector of the current frame is calculated in the following procedure.

  The outline is that among the horizontal motion vectors output from the vertical blocks of the current frame, the horizontal motion vector closest to the horizontal motion vector of the previous frame is used as the horizontal motion vector of the current frame.

  FIG. 21 shows a case where the difference between the maximum value and the minimum value of the distribution range of the horizontal motion vector obtained from each vertical block is 11, and is smaller than the threshold value B (for example, V = 31). The horizontal motion vector determination unit 32 determines that the horizontal motion vector calculated from each vertical block is reliable.

  Here, in FIG. 21, the horizontal motion vector 5 is the horizontal motion vector of the previous frame, and the horizontal motion vector obtained from each vertical block of the current frame closest to this is the horizontal motion vector 6. is there. Accordingly, the horizontal motion vector 6 is determined as the horizontal motion vector of the current frame. In FIG. 21, the sand corresponding to the horizontal motion vector obtained from each vertical block of the current frame is hatched, and the block corresponding to the horizontal motion vector of the previous frame is hatched. It is attached.

  Here, when the output results of a plurality of vertical blocks are the same horizontal motion vector, that is, when the number of certain horizontal motion vectors is 2 or more, the number of horizontal motion vectors of 1 is reliable. The horizontal motion vector closest to the horizontal motion vector of the previous frame is obtained as a lower motion vector, and the horizontal motion vector of the current frame may be used as the horizontal motion vector.

  When this method is adopted, in the example of FIG. 21, the horizontal direction motion vector 8 becomes the horizontal direction motion vector of the current frame.

  If there are two horizontal motion vectors closest to the horizontal motion vector of the previous frame, the average, that is, the horizontal motion vector of the previous frame itself may be used as the horizontal motion vector of the current frame. .

  Here, the information on the horizontal motion vector of the previous frame is stored in a predetermined storage unit (previous frame horizontal motion vector storage means) provided in the horizontal motion vector determination unit 32, and if necessary, It is configured to read.

  As described above, the vertical block having low reliability is excluded by the valid / invalid determination operation of the vertical block, and the horizontal direction motion vector calculated based on the vertical block having high reliability is varied. In consideration of the reliability of the horizontal motion vector of the entire image in consideration, even if it is determined to be reliable, the horizontal motion vector of the previous frame is taken into account, so that there is little uncomfortable feeling considering the motion from the previous frame A horizontal motion vector can be determined.

<Operation of Vertical Motion Vector Detection Unit 4>
Next, the operation of the vertical motion vector detection unit 4 that detects the vertical motion vector of the image in the motion vector detection device 1 will be described.

  As shown in FIG. 2, when a frame image read out by repeating the pixel scanning of the horizontal line in order in the vertical direction is input to the input terminal 40 of the vertical direction motion vector detection unit 4 shown in FIG. In 41, the blocks are horizontally divided. That is, the horizontal image dividing unit 41 sets a plurality of image regions (horizontal blocks) obtained by dividing the frame image in the horizontal direction. Thereby, in the subsequent processing, processing and management are performed for each horizontal block.

  In the horizontal image dividing unit 41, for example, as shown in FIG. 22A, image data of 640 pixels × 480 pixels is divided into ten vertical blocks hb0 to hb0 having a width of 64 pixels (divided width) in the horizontal direction. Divided into hb9. Note that the division width and the division number shown in FIG.

  The image divided into 10 horizontal blocks hb0 to hb9 as shown in FIG. 22A by the horizontal image dividing unit 41 is extracted, in other words, edge components extending in the horizontal direction by the horizontal edge extraction filtering unit 42. For example, a filtering process for emphasizing an image portion that changes sharply in the vertical direction is performed.

  As a filter used in this filtering processing, a (1, -1,) 2-tap filter that simply takes a difference from a pixel adjacent in the horizontal direction, or (-1, 2, -1) corresponding to a second order differential. It is possible to use a 3-tap filter. It is not essential to use such a filter, and any filter may be used as long as the output value increases in an image portion where the luminance change is large in the vertical direction.

  The image data in which the horizontal edge is enhanced for each horizontal block (image region) hb0 to hb9 by the horizontal edge extraction filtering unit 42 is input to the horizontal block projection unit 43, and the horizontal block projection unit 43 outputs the image data. Projected horizontally. This projection can reduce the noise component in the horizontal direction (between lines) and can further enhance the edge component in the horizontal direction, so that the horizontal edge corresponding to the feature point can be emphasized and the motion vector detection accuracy can be improved. It will be. The operation of the horizontal block projection unit 43 will be described with reference to the conceptual diagram of FIG.

  In the horizontal block projection unit 43, when the input of one horizontal line of each of the horizontal blocks hb0 to hb9 shown in FIG. 22A is completed, the horizontal block projection data hn0 having the data array Mh for one vertical line is completed. One array element of .about.hn9 (FIG. 22B) is generated. Therefore, all the array elements are arranged when the input of the final horizontal line of each horizontal block hb0 to hb9 is completed. The data array Mh has array elements of the total number of pixels of the vertical line (for example, 480), but in a 2-tap filter such as (1, -1), the effective element is the total number of pixels of the vertical line − In a 3-tap filter such as 1 (for example, 479) and (-1, 2, -1), the effective elements are the total number of pixels in the vertical line -2 (for example, 478).

  Specifically, as shown in FIG. 7, the image data (image data subjected to edge enhancement in the horizontal direction) of the horizontal blocks hb0 to hb9 input via the input terminal 431 is input to the adder 432. Is done. The adder 432 first writes the data in the horizontal projection temporary storage memory 433 without reading the data in the horizontal projection temporary storage memory 433 at the head of one horizontal line of the input horizontal block. Next, the adder 432 reads the addition result up to the previous pixel of one horizontal line stored in the horizontal projection temporary storage memory 433, and the current pixel of one horizontal line of the horizontal block input from the input terminal 431. And the addition result is written back to the horizontal projection temporary storage memory 433. When the final pixel of one horizontal line in the horizontal block is input to the adder 432, the addition result up to the previous pixel stored in the horizontal projection temporary storage memory 433 is read and the horizontal input from the input terminal 431 is read. Addition with the final pixel of one horizontal line of the direction block, and output the addition result, that is, data obtained by adding all the pixels of one horizontal line of the horizontal block as projection data for one horizontal line of the horizontal block The data is output from the terminal 434 to the first horizontal block projection line memory 44 and the first horizontal block projection data maximum value storage unit 45. The projection data obtained by adding all the pixels of one horizontal line of the horizontal block in the adder 432 is temporarily stored in the horizontal projection temporary storage memory 433, and the first pixel of one horizontal line of the next horizontal block is input. In this case, the projection data in the horizontal projection temporary storage memory 433 may be read out and output from the output terminal 434.

  The first horizontal block projection line memory 44 stores the horizontal block projection data of the current frame input from the horizontal block projection unit 43 for each horizontal block as first horizontal block projection data.

  The first horizontal block projection data maximum value storage unit 45 calculates the maximum value related to the projection data of the horizontal block inputted from the horizontal block projection unit 43 and stores it as the horizontal block projection data maximum value of the current frame. To do.

  The second horizontal block projection line memory 46 stores the horizontal block projection data read from the first horizontal block projection line memory 44 as second horizontal block projection data related to the previous frame. Similarly, in the second horizontal block projection data maximum value storage unit 47, the maximum value of the horizontal block projection data output from the first horizontal block projection data maximum value storage unit 45 is the second value related to the previous frame. Is stored as the maximum horizontal block projection data. In other words, the maximum value of the horizontal block projection data of the current frame stored in the first horizontal block projection data maximum value storage unit 45 is stored in the second horizontal block projection data maximum value of the next frame. This is stored in the unit 47 as the maximum value of the horizontal block projection data of the previous frame.

  The second horizontal block projection data maximum value storage unit 47 calculates a fourth threshold value based on the calculated horizontal block projection data maximum value of the previous frame. For example, if the maximum value related to the projection data of the horizontal block of the previous frame is P4max, the fourth threshold value α4 is calculated by the following equation (3).

  α4 = P4max × k4 (3)

  Here, k4 is a predetermined coefficient, and 0 <k4 <1.

  Note that the calculation of the fourth threshold value α4 is not limited to the above equation (3), and it is sufficient if the fourth threshold value α4 increases as the horizontal block projection data maximum value P4max of the previous frame increases. Alternatively, a conversion table may be used. For the fourth threshold α4, it is not essential to use the maximum value of the second horizontal block projection data for each horizontal block. For example, the maximum horizontal block projection data for the entire image of the previous frame is used. The fourth threshold value may be calculated using the value, and the same fourth threshold value may be employed for the entire image.

  The second horizontal block projection data maximum value storage unit 47 sets a third threshold (predetermined constant value) based on the maximum value of the second horizontal block projection data regarding the previous frame. For example, if the maximum value of the horizontal block projection data of the previous frame is P3max, the third threshold value α3 is calculated by the following equation (4).

  α3 = P3max × k3 (4)

  Here, k3 is a predetermined coefficient, and 0 <k3 <1.

  Note that the calculation of the third threshold value α3 is not limited to the above equation (4), and it is sufficient if the third threshold value α3 increases as the horizontal block projection data maximum value P3max of the previous frame increases. Alternatively, a conversion table may be used. For the third threshold α3, it is not essential to use the maximum value of the second horizontal block projection data for each horizontal block. For example, the maximum horizontal block projection data for the entire image of the previous frame is used. The third threshold value may be calculated using the value, and the same third threshold value may be adopted for the entire image.

  The third threshold intersection search unit 48 outputs the second horizontal block projection data read from the second horizontal block projection line memory 46 and the second horizontal block projection data maximum value storage unit 47. The intersection with the third threshold value (third threshold value intersection) is searched in the vertical direction. The information on the third threshold intersection obtained by the third threshold intersection searching unit 48 is input to the horizontal block projection data reading unit 49 and the horizontal block vertical motion vector calculating unit 50.

  The horizontal block projection data reading unit 49 outputs the (first) horizontal block projection of the current frame corresponding to the motion vector detection range centered on the third threshold intersection output from the third threshold intersection search unit 48. Data is read from the first horizontal block projection line memory 44. That is, the third threshold intersection is B (i) (where i = 1, 2,... Q, q is the total number of detected third threshold intersections), and the motion vector detection range is the third threshold. Assuming the range from (−U) to (+ U) (where U is a positive integer) centered on the intersection, the projection data read from the first horizontal block projection line memory 44 is (B (i ) −U) to (B (i) + U), which is partial data of the first horizontal block projection data.

  The first horizontal block projection data read from the first horizontal block projection line memory 44 by the horizontal block projection data reading unit 49 is output to the horizontal block vertical motion vector calculation unit 50.

  The first horizontal block projection data output from the horizontal block projection data reading unit 49 is input to the n-value converter 504 via the input terminal 501 of the horizontal block vertical motion vector calculation unit 50 shown in FIG. Is done. The n-value converter 504 outputs the first horizontal block projection data based on the fourth threshold value output from the second horizontal block projection data maximum value storage unit 47 and input via the input terminal 502. n-valued. That is, the n-value converter 504 compresses the data length of each array element of the data array Mh (FIG. 22B) regarding the projection data of the current frame extracted by the horizontal block projection data reading unit 49. About the process of this n value digitizer 504, the process similar to the n value digitizer 314 mentioned above is performed, for example, a 3 value process is performed. That is, in the ternarization processing in the n-value quantizer 504, the horizontal block projection is performed with respect to the fourth threshold value α4 (α4> 0) set based on the maximum value of the array element of the data array Mh in the projection data of the previous frame. Three values in three stages when the value of the array element relating to the projection data of the current frame extracted by the data reading unit 49 is smaller than (−α4), (−α4) or more and α4 or less, and greater than α4. Is done. Note that the n-value generator 504 does not necessarily have the same characteristics as the n-value generator 314, and may have different characteristics from the n-value generator 314.

  The operations of the third threshold intersection searching unit 48, the horizontal block projection data reading unit 49, and the horizontal block vertical motion vector calculating unit 50 described above are shown in FIGS. 23 (a), 23 (b), and 23. This will be specifically described with reference to (c). Note that the horizontal axes of FIGS. 23A and 23B indicate the positions of the array elements of the projection data array Mh (FIG. 22B). In FIG. 23A, each of the third threshold intersections B (1) to B (6) is indicated by a circle.

  The third threshold value intersection search unit 48 outputs the second horizontal block projection data maximum value storage unit 47 in the waveform of the second vertical block projection data W4 related to the previous frame as shown in FIG. The third threshold value intersections B (1) to B (6) that intersect with the third threshold value α3 are obtained. That is, the third threshold value intersection search unit 48 sets the array element values in the order of the elements in the projection data array Mh (FIG. 22B) with respect to the projection data obtained by the horizontal block projection unit 43 with respect to the previous frame. The position of the array element at each of the third threshold intersections where the waveform W4 and the straight line where the value of the array element is the third threshold value (predetermined constant value) α3 intersect is specified.

  Next, in the horizontal block projection data reading unit 49, a first horizontal vector is detected for a predetermined motion vector detection range centered on each of the third threshold intersections B (1) to B (6) shown in FIG. The horizontal block projection data of the current frame is read from the direction block projection line memory 44. That is, the horizontal block projection data reading unit 49 obtains a data array in a predetermined range centered on the position of the array element of the projection data (data array) at each third threshold intersection at the horizontal block projection unit 43. Extracted from the projection data of the current frame (back frame). For example, for the third threshold value intersection B (4), as shown in FIG. 23B, the third threshold value intersection B (4) is centered on (B (4) -U) to (B (4) + U). The first horizontal block projection data W3 corresponding to the range up to (the waveform portion within the rectangular broken line) is read out.

  The first horizontal block projection data read out by the horizontal block projection data reading unit 49 uses the fourth threshold value α4 output from the second horizontal block projection data maximum value storage unit 47. The n-value unit 504 of the horizontal block vertical motion vector calculation unit 50 performs n-value processing. For example, for the third threshold value intersection B (4), the third threshold value is based on the magnitude relationship of the first horizontal block projection data W3 with respect to the fourth threshold values α4 and (−α4) shown in FIG. For the range from (B (4) -U) to (B (4) + U) centered on the intersection B (4) (the waveform portion within the rectangular broken line), the first horizontal as shown in FIG. The direction block projection data is ternarized. As a result, the horizontal block projection data of the current frame is represented by “−1”, “0”, or “1”.

  The n-value converter 504 performs n-value conversion processing as shown in FIG. 23C for all the third threshold value intersections output from the third threshold value intersection search unit 48.

  Next, the adder 505 (FIG. 8) is n-valued by the n-value generator 504 around the third threshold value intersection output from the third threshold value intersection search unit 48 via the input terminal 503. The first horizontal block projection data is added to the addition value of the first horizontal block projection data converted to n-values read from the vertical motion vector addition memory 506, and the addition is performed. The result is stored again in the vertical motion vector addition memory 506. Then, the adder 505 adds the n-valued first horizontal block projection data regarding the last one of all the third threshold intersections detected by the third threshold intersection search unit 48 to obtain one When the addition process for the horizontal block is finished, the addition result is output to the peak detector 507. In addition, after the addition process in the adder 505 is completed, the peak detection unit 507 may read out the addition result from the vertical motion vector addition memory 506 storing the addition results regarding all the third threshold intersections. good.

  The peak detector 507 includes a motion vector detection range (the above-described ± U range) centered on each third threshold intersection for all the third threshold intersections detected by the third threshold intersection search unit 48. Data obtained by adding the corresponding n-valued first horizontal block projection data (hereinafter also referred to as “horizontal block n-valued data”) is input. The value is detected by peak detector 507. The peak position of the horizontal block n-valued data detected by the peak detector 507 becomes the vertical motion vector obtained from the horizontal block, and is output to the vertical motion determination unit 51 via the output terminal 508. . Similarly, the peak value at that time is output from the output terminal 509.

  The operations of the adder 505 and the peak detector 507 described above will be specifically described with reference to FIGS. 24 (a) and 24 (b). In FIG. 24A, the first horizontal direction in the motion vector detection range (± U range) centering on the third threshold intersections B (1) to B (6) shown in FIG. The block projection data is conceptually shown as three values.

  In the adder 505, when ternary data around the third threshold intersections B (1) to B (6) shown in FIG. 24 (a) are sequentially input, these data are added, and FIG. Horizontal block n-valued data as shown in b) is generated. Specifically, in the adder 505, the horizontal block projection data reading unit 49 extracts the horizontal block projection data (data array Mh (FIG. 22B)) and the n-value unit 504 compresses the data length. For each data array of the motion vector detection range (predetermined range) related to the frame, values of array elements having the same relative position with respect to the position of the array element at each third threshold intersection are added.

  When the horizontal block n-valued data generated by the adder 505 is input to the peak detector 507, the vertical peak position vv shown in FIG. 24B is detected as the vertical motion vector of the horizontal block. Is done. That is, the peak detector 507 detects a motion vector in the vertical direction of the frame image based on the addition result added by the adder 505.

  In principle, the peak detector 507 searches for a peak position having a maximum value in the motion vector detection range (± U range). When there are a plurality of the same maximum values, the peak detector 507 is close to the origin 0 ( If the distance to the origin 0 is the same, the negative position) is given priority. It should be noted that the maximum value at the positive position may be prioritized without being limited to such a peak position detection rule, and the tendency of the motion vector in the previous frame is used for detection of the peak position in the current frame. Also good.

  The vertical motion vector (peak position) calculated for each horizontal block by the peak detector 507 and the peak value of the added data obtained by adding the n-valued horizontal block (hereinafter referred to as “horizontal block n-valued addition”). The data peak value ”is also input to the vertical motion vector determination unit 51 via the output terminals 508 and 509, respectively, and the horizontal block n-valued addition data peak value is used to determine whether the horizontal block is valid / invalid. used.

  In the vertical direction motion vector determination unit 51 (FIG. 6), the vertical direction motion vector of the entire image is determined based on the vertical direction motion vector of each horizontal direction block sequentially output from the horizontal direction block vertical direction motion vector calculation unit 50. Is done.

  At this time, in the vertical direction motion vector determination unit 51, the maximum value of the first horizontal direction block projection data output from the first horizontal direction block projection data maximum value storage unit 45, the horizontal direction block vertical direction motion vector calculation unit On the basis of the horizontal block n-valued addition data peak value output from 50 and the information on the third threshold intersection output from the third threshold intersection search unit 48, the validity / invalidity of each horizontal block is determined. The vertical motion vector calculated from the horizontal block determined to be an invalid block is not used when determining the vertical motion vector of the entire image.

<Horizontal block validity / invalidity judgment operation>
<When using the maximum value of the first horizontal block projection data>
Hereinafter, a method for determining validity / invalidity of each horizontal block will be described.
FIG. 25 is a diagram illustrating a method for determining validity / invalidity of each horizontal block using the maximum value of the first horizontal block projection data.

  In FIG. 25, the image data of 640 pixels × 480 pixels shown in FIG. 22A is taken as an example, and 10 horizontal blocks hb0 to hb9 having a width of 64 pixels (divided width) in the horizontal direction are arranged. This shows the case of division.

  In FIG. 25, the maximum value of the first horizontal block projection data of each horizontal block output from the first horizontal block projection data maximum value storage unit 45 (FIG. 6) is set for each block. It is shown in hexadecimal notation.

  The vertical motion vector determination unit 51 obtains the maximum value in all blocks from the maximum value of the first horizontal block projection data in each of the horizontal blocks hb0 to hb9. In the example of FIG. 25, the horizontal block hb4 has the maximum value in all blocks, and this value is referred to as the all horizontal block projection data maximum value.

  In addition, the vertical direction motion vector determination unit 51 determines, as an invalid block, a horizontal direction block having, for example, a maximum value equal to or less than 1/4 with respect to the maximum value of all horizontal block projection data. In the example of FIG. 25, the horizontal blocks hb0, hb1, hb8 and hb9 are determined to be invalid blocks.

FIG. 26 is a diagram schematically illustrating determination of validity / invalidity of a horizontal block.
In FIG. 26, a graph is shown in which the horizontal axis represents the maximum value of all horizontal block projection data and the vertical axis represents the first horizontal block projection data maximum value, and the slope 1/4 (S = 1/4) is divided into valid blocks and invalid blocks.

  A horizontal block that is determined to be an invalid block can be said to have a few features (there are few clear parts) or a very fine design as a pattern, and as a result, it is reliable with respect to other valid blocks. It can be judged that the nature is low. Therefore, the reliability of the vertical motion vector can be improved by not using the horizontal block determined to be an invalid block for determining the vertical motion vector of the entire image.

In the above description, the valid / invalid determination condition is described as being ¼ or less of the maximum value of all horizontal block projection data. However, the present invention is not limited to this, and may be ½ or less or 1 / It may be 8 or less. In this way, by setting with the determination condition 1/2 ⁿ , it is possible to easily determine whether it is valid or invalid.

<When using a horizontal block n-valued addition data peak value>
FIG. 27 is a diagram for explaining a method of determining validity / invalidity of each horizontal block using the horizontal block n-valued addition data peak value.

  In FIG. 27, the image data of 640 pixels × 480 pixels shown in FIG. 22A is taken as an example, and 10 horizontal blocks hb0 to hb9 having a width (divided width) of 64 pixels in the vertical direction are shown. This shows the case of division.

  In FIG. 27, the horizontal block n-valued addition data peak value of each horizontal block output from the horizontal block vertical motion vector calculation unit 50 (FIG. 6) is expressed in hexadecimal notation for each block. Show.

  The vertical motion vector determination unit 51 obtains the maximum value from the horizontal block n-valued addition data peak values in the horizontal blocks hb0 to hb9. In the example of FIG. 27, the horizontal block hb4 has the maximum value, and this value is referred to as the maximum value of the horizontal block n-valued addition data peak value.

  Also, in the vertical direction motion vector determination unit 51, when the maximum value of the horizontal block n-valued addition data peak value is equal to or greater than a predetermined value A (for example, 12 in decimal notation), the horizontal direction block n-valued addition data is A horizontal block having a predetermined value B (for example, 7 in decimal notation) or less is determined as an invalid block. In the example of FIG. 27, the vertical blocks hb0, hb1, hb7, hb8 and hb9 are determined to be invalid blocks.

  The output of the adder 505 (FIG. 8) of the horizontal block vertical motion vector calculation unit 50 (FIG. 6) is the first horizontal direction centered on the third threshold intersection and n-valued with the fourth threshold. This is a sum of block projection data, and the larger the third threshold value intersection and the larger the amplitude (mountain) exceeding the fourth threshold value (α4) on the plus side, the larger the value. On the other hand, if there is an amplitude exceeding the negative fourth threshold (−α4), it is canceled out.

  In other words, the maximum value of the output of the adder 505, that is, the horizontal block n-valued addition data peak value of a certain horizontal block is equal to or greater than the predetermined value A, while the horizontal blocks of other horizontal blocks When the n-valued addition data peak value is equal to or less than the predetermined value B, it can be said that the other horizontal block is a picture with the addition result canceled or a picture with few features and small amplitude.

  Accordingly, it can be determined that a block whose horizontal block n-valued addition data peak value is equal to or smaller than the predetermined value B is less reliable than a block whose predetermined value is equal to or greater than A. Therefore, the reliability of the vertical motion vector can be improved by not using the horizontal block determined to be an invalid block for determining the vertical motion vector of the entire image.

FIG. 28 is a diagram schematically illustrating whether the horizontal block is valid / invalid.
28 shows a graph in which the horizontal axis represents the maximum value of the horizontal block n-valued addition data peak value, and the vertical axis represents the horizontal block n-value addition data peak value. When the maximum value of the added data peak value is equal to or greater than the predetermined value A, an operation is illustrated in which a horizontal block whose horizontal block n-valued added data is equal to or smaller than the predetermined value B is determined as an invalid block.

  In FIG. 28, when the maximum value of the horizontal block n-valued addition data peak value is smaller than the predetermined value A, there is a block whose horizontal block n-valued addition data peak value is equal to or less than the predetermined value B. Even so, the operation of not determining that the block is an invalid block is also shown.

  For example, taking FIG. 27 as an example, if the maximum value of the horizontal block n-valued addition data peak value is 7, the vertical blocks hb0, hb1, hb7, hb8 and hb9 are not determined to be invalid blocks. This is because it cannot be said that the reliability is relatively low with respect to the block whose horizontal block n-valued addition data peak value is the maximum value.

  In the above description, an example in which the valid / invalid determination condition is set to 12 for the predetermined value A and 7 for the predetermined value B is not limited to this. For example, when the number of pixels in the vertical direction is 480 pixels, the predetermined value A may be set to a value of about 10, and the predetermined value B may be set to a value around half of that.

<When using the number of third threshold intersections>
FIG. 29 is a diagram illustrating a method of determining validity / invalidity of each vertical block using the number of third threshold intersections.

  In FIG. 29, the image data of 640 pixels × 480 pixels shown in FIG. 22A is taken as an example, and ten horizontal blocks hb0 to hb9 having a width of 64 pixels (divided width) in the vertical direction are shown. This shows the case of division.

  Further, in FIG. 29, the number of third threshold intersections output from the third threshold intersection searching unit 48 (FIG. 6) is shown in hexadecimal notation for each block.

  In the third threshold intersection searching unit 48, the waveform of the second horizontal block projection data relating to the previous frame stored in the second horizontal block projection line memory 46 and the second horizontal block projection data maximum value are stored. Information on the third threshold value intersection at which the third threshold value calculated by the storage unit 45 intersects is output. This information also includes information on the number of third threshold value intersections, as shown in FIG. As shown, the number of third threshold intersections is obtained for each horizontal block hb0-hb9.

FIG. 30 is a diagram schematically illustrating determination of validity / invalidity of a horizontal block.
FIG. 30 shows a graph in which the horizontal axis represents the maximum number of third threshold intersections in each of the horizontal blocks hb0 to hb9, and the vertical axis represents the number of third threshold intersections. In the determination unit 51 (FIG. 6), the third threshold value intersection is determined for blocks whose number of third threshold intersections in each of the horizontal blocks hb0 to hb9 is equal to or less than a predetermined value D (for example, 3 in decimal notation). Regardless of the maximum value, it is determined as an invalid block. In the example of FIG. 29, the horizontal blocks hb0 and hb9 are determined to be invalid blocks.

  The reliability of the vertical motion vector can be enhanced by not using the horizontal block determined to be an invalid block for determining the vertical motion vector of the entire image.

  On the other hand, the number of the third threshold intersections is at least equal to or less than the number of pixels in the vertical direction, and if the number is too large compared to the number of pixels in the vertical direction, it can be said that a very periodic pattern is captured. For example, when the value is equal to or greater than a predetermined value E (for example, more than half of the number of pixels in the vertical direction), the block may be determined as an invalid block. For example, in the horizontal block hb4 of FIG. 29, the number of third threshold intersections is 241 and is more than half of the number of vertical pixels, so it is determined as an invalid block.

  Further, as shown in FIG. 31, only when the maximum value of the number of third threshold intersections is equal to or greater than a predetermined value C (> D), a block having a predetermined value D or less is determined to be an invalid block. You may do it. In this case, if the maximum value of the number of the third threshold intersections is smaller than the predetermined value C, even if there is a block equal to or smaller than the predetermined value D, the block is not determined as an invalid block, and the invalid block Can be set more finely.

  In the above description, an example in which the valid / invalid determination condition is such that the predetermined value D is 3 and the predetermined value E is half the number of pixels in the vertical direction is not limited to this.

  The method for determining validity / invalidity of each horizontal block using the maximum value of the first horizontal block projection data described above, and the validity / invalidity of each horizontal block using the horizontal block n-valued addition data peak value An invalid block is determined by using a method for determining invalidity and a method for determining validity / invalidity of each horizontal block by using the information of the third threshold intersection, and is calculated from the horizontal block that is determined as an invalid block By not using the vertical motion vector when determining the vertical motion vector of the entire image, the reliability of the motion vector can be improved.

  Further, the above-described three determination methods may be used alone or in combination.

  For example, the validity / invalidity is determined using the maximum value of the first horizontal block projection data, and the validity / invalidity of each horizontal block is determined using the horizontal block n-valued addition data peak value. The validity / invalidity may be determined using the maximum value of the first horizontal block projection data, and the validity / invalidity of each horizontal block may be determined using the third threshold intersection information.

  With such a combination, an invalid block can be reliably selected, and the reliability of the motion vector can be further improved.

<Method for determining vertical motion vector>
As described above, the vertical motion vector determination unit 51 determines the validity / invalidity of the horizontal block, and determines the vertical motion vector of the entire image from the vertical motion vector for the horizontal block determined to be a valid block. To do.

  At this time, horizontal blocks having the same vertical motion vector are collected to create a histogram.

  Hereinafter, an example of a method for determining the vertical motion vector of the entire image will be described with reference to FIGS. 32 and 33.

  32 and 33 show the case where the detection range of the horizontal motion vector is -V to V. Here, the case where V is 31 is shown as an example, and one vector from -31 to 31 is shown. Displayed at intervals. The numbers displayed in the boxes provided corresponding to the vectors represent the number of horizontal blocks having the same vector.

  As shown in FIG. 32, among the vertical motion vectors calculated for each horizontal block, the vertical motion vector-3 and the vertical motion vector 2 are calculated with two horizontal blocks. In the horizontal block, all the vertical motion vectors are disjoint, the minimum value of the distribution range is −26, the maximum value is 8, and the difference 34 is very large with respect to the motion vector detection range. It can be said that there is variation. In FIG. 32, the sand corresponding to the vertical motion vector obtained from each horizontal block in the current frame is hatched.

  In the vertical direction motion vector determination unit 51, when the difference between the maximum value and the minimum value of the vertical direction motion vector obtained from each horizontal block is equal to or greater than a predetermined threshold B (for example, V described above), each horizontal direction block The vertical motion vector obtained from the above is assumed to have low reliability, and the vertical motion vector is set to zero.

  By performing such processing, the reliability of the horizontal motion vector of the entire image can be increased.

  On the other hand, when the number of horizontal blocks having the vertical motion vector-3 and the vertical motion vector 2 is equal to or greater than a predetermined numerical value A (eg, 3), the vertical motion vector obtained from each horizontal block is Judge that it is reliable enough.

  Similarly, when the difference between the maximum value and the minimum value of the vertical motion vector obtained from each horizontal block is smaller than the threshold value B, it is determined that the vertical motion vector obtained from each horizontal block is sufficiently reliable. To do.

  Note that the numerical value A and the threshold value B are not limited to the values described above. Further, the determination of the variation is not limited to the above-described difference between the maximum value and the minimum value of the vertical motion vector, and the standard deviation is used. For example, when the standard deviation is greater than or equal to the threshold B, the variation is large. You may judge.

  As a result of the above-described processing, when it is determined that the vertical motion vector obtained from each horizontal block is sufficiently reliable, the vertical motion vector of the current frame is calculated by the following procedure.

  The outline is that among the vertical motion vectors output from the horizontal blocks of the current frame, the vertical motion vector closest to the vertical motion vector of the previous frame is used as the vertical motion vector of the current frame.

  FIG. 33 shows a case where the difference between the maximum value and the minimum value of the vertical motion vector distribution range obtained from each horizontal block is 9, and is smaller than the threshold value B (for example, V = 31). The vertical motion vector determination unit 51 determines that the vertical motion vector calculated from each horizontal block is reliable.

  Here, in FIG. 33, the vertical motion vector 8 is the vertical motion vector of the previous frame, and the vertical motion vector obtained from each horizontal block of the current frame closest to this is the vertical motion vector 6. is there. Accordingly, the vertical motion vector 6 is determined as the vertical motion vector of the current frame. In FIG. 33, the sand corresponding to the vertical motion vector obtained from each horizontal block of the current frame is hatched, and the block corresponding to the vertical motion vector of the previous frame is hatched. It is attached.

  Here, when the output results of a plurality of horizontal blocks are the same vertical motion vector, that is, when the number of certain vertical motion vectors is 2 or more, the number of vertical motion vectors of 1 is reliable. The vertical motion vector closest to the vertical motion vector of the previous frame is obtained as a lower motion vector, and the vertical motion vector of the current frame may be used as the vertical motion vector of the current frame.

  When this method is adopted, in the example of FIG. 33, the vertical motion vector 5 becomes the horizontal motion vector of the current frame.

  If there are two vertical motion vectors that are closest to the vertical motion vector of the previous frame, the average, that is, the vertical motion vector of the previous frame itself may be used as the vertical motion vector of the current frame. .

  Here, the information on the vertical motion vector of the previous frame is stored in a predetermined storage unit (previous frame vertical motion vector storage means) provided in the vertical motion vector determination unit 51, and if necessary, It is configured to read.

  As described above, after the horizontal block having low reliability is excluded by the determination operation of the validity / invalidity of the horizontal block, the vertical motion vector calculated based on the horizontal block having high reliability is varied. Considering the vertical motion vector reliability of the entire image, considering the reliability of the entire image in consideration of the vertical motion vector of the previous frame, even if it is determined to be reliable, there is little uncomfortable feeling considering the motion from the previous frame A vertical motion vector can be determined.

<Effect>
As described above, in the horizontal direction motion vector detection unit 2 of the motion vector detection device 1 according to Embodiment 1, the horizontal direction motion vector determination unit 32 includes the first vertical block projection data maximum value storage unit. 24. The maximum value of the first vertical block projection data output from 24, the vertical block n-valued addition data peak value output from the vertical block horizontal motion vector calculation unit 31, and the first threshold value intersection search unit 29 Based on the information on the first threshold intersection output from, it is possible to exclude the horizontal motion vector obtained from the low-reliability vertical block in order to determine the validity / invalidity of the vertical block, As a result, a highly reliable horizontal motion vector can be calculated.

  In addition, if the reliability of the horizontal motion vector of the entire image is evaluated by considering the variation of the horizontal motion vector calculated based on the highly reliable vertical block, and the frame is determined to be reliable, By considering the horizontal direction motion vector, it is possible to determine a horizontal direction motion vector with less sense of incongruity in consideration of the motion from the previous frame.

  Further, in the vertical direction motion vector detection unit 4, the maximum value of the first horizontal direction block projection data output from the first horizontal direction block projection data maximum value storage unit 45 in the vertical direction motion vector determination unit 51, Based on the horizontal block n-valued addition data peak value output from the horizontal block vertical motion vector calculation unit 50 and the third threshold intersection information output from the third threshold intersection search unit 48, the horizontal direction Since the validity / invalidity of the block is determined, the vertical motion vector obtained from the horizontal block with low reliability can be excluded, and as a result, the vertical motion vector with high reliability can be calculated. it can.

  In addition, when the reliability of the vertical motion vector of the entire image is evaluated by considering the variation of the vertical motion vector calculated based on the highly reliable horizontal block, and the frame is determined to be reliable, By considering the vertical direction motion vector, it is possible to determine a vertical direction motion vector with less sense of incongruity considering the motion from the previous frame.

<Embodiment 2>
<Configuration of motion vector detection device>
The motion vector detection device 1A according to the second embodiment of the present invention has a configuration similar to that of the motion vector detection device 1 according to the first embodiment shown in FIG. 1, but is perpendicular to the horizontal motion vector detection unit. The configuration differs from that of the directional motion vector detection unit. Configurations of the horizontal direction motion vector detection unit 2A and the vertical direction motion vector detection unit 4A in the motion vector detection device 1A will be described with reference to FIGS. 34 and 35. FIG.

  FIG. 34 is a block diagram showing a main configuration of the horizontal direction motion vector detection unit 2A. In FIG. 34, parts having the same functions as those in the first embodiment are denoted by the same reference numerals.

  In the horizontal direction motion vector detection unit 2A, the arrangement of the vertical direction image division unit 21 and the vertical direction edge extraction filtering unit 22 is reversed with respect to the horizontal direction motion vector detection unit 2 of the first embodiment. Below, operation | movement of this horizontal direction motion vector detection part 2A is demonstrated.

  As shown in FIG. 2, when a frame image read by sequentially repeating pixel scanning of the horizontal line in the vertical direction is input to the input terminal 20 of the horizontal motion vector detection unit 2A, the vertical edge extraction filtering unit 22 Extraction of edge components extending in the vertical direction, in other words, filtering processing for emphasizing image portions that change sharply in the horizontal direction is performed.

  When the frame image in which the vertical edge is emphasized by the vertical edge extraction filtering unit 22 is input to the vertical image dividing unit 21, it is divided into blocks in the vertical direction. That is, the vertical image dividing unit 21 sets a plurality of image regions (vertical blocks) obtained by dividing the frame image subjected to edge enhancement in the vertical direction. As a result, in the subsequent processing, processing and management are performed for each vertical block.

  The image data divided by the vertical image dividing unit 21 is input to the vertical block projecting unit 23. The processes after the vertical block projecting unit 23 are the horizontal direction motion vector detecting unit 2 of the first embodiment. The same processing is performed.

  FIG. 35 is a block diagram showing a main configuration of the vertical motion vector detection unit 4A. In FIG. 35, parts having the same functions as those in the first embodiment are denoted by the same reference numerals.

  In the vertical direction motion vector detection unit 4A, the arrangement of the horizontal direction image division unit 41 and the horizontal direction edge extraction filtering unit 42 is reversed with respect to the vertical direction motion vector detection unit 4 of the first embodiment. Hereinafter, the operation of the vertical motion vector detection unit 4A will be described.

  As shown in FIG. 2, when a frame image read out by repeating the pixel scanning of the horizontal line in order in the vertical direction is input to the input terminal 40 of the vertical direction motion vector detection unit 4A, the horizontal direction edge extraction filtering unit 42 Extraction of the edge component extending in the horizontal direction, in other words, filtering processing for emphasizing an image portion that changes sharply in the vertical direction is performed.

  When the frame image in which the horizontal edge is emphasized by the horizontal edge extraction filtering unit 42 is input to the horizontal image dividing unit 41, the frame image is divided into blocks in the horizontal direction. That is, the horizontal image dividing unit 41 sets a plurality of image regions (horizontal blocks) obtained by dividing the frame image subjected to edge enhancement in the horizontal direction. Thereby, in subsequent processing, processing and management are performed for each horizontal block.

  The image data divided by the horizontal image dividing unit 41 is input to the horizontal block projecting unit 43. The processing after the horizontal block projecting unit 43 is the vertical motion vector detecting unit 4 of the first embodiment. The same processing is performed.

  The operation of the motion vector detection device 1A described above provides the same effects as those of the first embodiment.

  Then, in the motion vector detection device 1A, the vertical edge extraction filtering unit 22 emphasizes the edge in the vertical direction with respect to the frame image, and then the vertical image dividing unit 21 divides the frame image subjected to edge enhancement in the vertical direction. A divided image with emphasized vertical edges can be easily generated.

  Similarly, the horizontal edge extraction filtering unit 42 emphasizes the horizontal edge of the frame image, and then the edge-enhanced frame image is divided in the horizontal direction by the horizontal image dividing unit 41. Therefore, the horizontal edge is emphasized. The divided image can be easily generated.

  In the motion vector detection device 1A, it is essential to arrange the vertical edge extraction filtering unit 22 and the horizontal edge extraction filtering unit 42 separately in the horizontal motion vector detection unit 2A and the vertical motion vector detection unit 4A. In addition, a horizontal / vertical edge extraction filtering unit in which the functions of both the vertical edge extraction filtering unit 22 and the horizontal edge extraction filtering unit 42 are integrated is provided, and the output is provided to the vertical image dividing unit 21 and the horizontal direction. You may make it make each image division part 41 input.

<Modification>
For the vertical direction edge extraction filtering unit and the horizontal direction edge extraction filtering unit in each of the above embodiments, after the filtering process for performing edge extraction, for example, “with edge” and “ The binarization of “no edge” or the ternarization of “with positive edge”, “without edge”, and “with negative edge” may be performed. By performing such threshold processing, it is possible to treat edges having a luminance change (luminance gradient) equal to or greater than a predetermined threshold in the same way.

  In each of the above-described embodiments, the data output from the bit number reduction unit 25 is converted into the first vertical block projection line memory 26 and the second vertical block projection line memory 27 by, for example, switch switching for each frame. You may make it input alternately. Further, the data output from the horizontal block projection unit 43 is alternately input to the first horizontal block projection line memory 44 and the second horizontal block projection line memory 46 by, for example, switch switching for each frame. Anyway. Similarly, the data output from the vertical (horizontal) direction block projection unit is converted into, for example, a first vertical (horizontal) direction block projection data maximum value storage unit and a second vertical (horizontal) direction block by switching switches for each frame. Alternatively, the data may be alternately input to the projection data maximum value storage unit.

  The “previous frame” in the present invention is not limited to the previous frame, but includes two or more previous frames (for example, the current frame). For example, when a frame in the middle is skipped by the frame thinning process, the frame before the skipped frame is included.

It is a block diagram which shows the principal part structure of the motion vector detection apparatus 1 (1A) which concerns on Embodiment 1 of this invention. It is a figure for demonstrating the pixel scanning direction in a frame image. 3 is a block diagram showing a main configuration of a horizontal motion vector detection unit 2. FIG. FIG. 4 is a block diagram showing a main configuration of a vertical block projection unit 23. FIG. 6 is a block diagram showing a main configuration of a vertical block horizontal motion vector calculation unit 31. FIG. 3 is a block diagram illustrating a main configuration of a vertical motion vector detection unit 4. FIG. 4 is a block diagram illustrating a main configuration of a horizontal block projection unit 43. FIG. 6 is a block diagram showing a main configuration of a horizontal block vertical motion vector calculation unit 50. It is a figure for demonstrating operation | movement of the vertical direction image division part 21 and the vertical direction block projection part 23. FIG. It is a figure for demonstrating the n-value-izing process in the n-value-converter 314 and the n-value-converter 504. It is a figure for demonstrating operation | movement of the 1st threshold value intersection search part 29, the vertical direction block projection data reading part 30, and the vertical direction block horizontal direction motion vector calculation part 31. FIG. 6 is a diagram for explaining operations of an adder 315 and a peak detector 317. FIG. It is a figure explaining the method to determine the validity / invalidity of each vertical direction block using the maximum value of 1st vertical direction block projection data. It is a figure which shows typically the determination of the validity / invalidity of a vertical direction block. It is a figure explaining the method to determine the validity / invalidity of each vertical direction block using a vertical direction block n-valued addition data peak value. It is a figure which shows typically the determination of the validity / invalidity of a vertical direction block. It is a figure explaining the method to determine the validity / invalidity of each vertical direction block using the number of 1st threshold value intersections. It is a figure which shows typically the determination of the validity / invalidity of a vertical direction block. It is a figure which shows typically the determination of the validity / invalidity of a vertical direction block. It is a figure explaining an example of the determination method of the horizontal direction motion vector of the whole image. It is a figure explaining an example of the determination method of the horizontal direction motion vector of the whole image. It is a figure for demonstrating operation | movement of the horizontal direction image division part 41 and the horizontal direction block projection part 43. FIG. It is a figure for demonstrating operation | movement of the 3rd threshold value intersection search part 48, the horizontal direction block projection data reading part 49, and the horizontal direction block vertical direction motion vector calculation part 50. FIG. FIG. 10 is a diagram for explaining operations of an adder 505 and a peak detection unit 507. It is a figure explaining the method to determine the validity / invalidity of each horizontal direction block using the maximum value of 1st horizontal direction block projection data. It is a figure which shows typically the determination of validity / invalidity of a horizontal direction block. It is a figure explaining the method to determine the validity / invalidity of each horizontal direction block using a horizontal direction block n-valued addition data peak value. It is a figure which shows typically the determination of validity / invalidity of a horizontal direction block. It is a figure explaining the method to determine the validity / invalidity of each horizontal direction block using the number of 3rd threshold value intersections. It is a figure which shows typically the determination of validity / invalidity of a horizontal direction block. It is a figure which shows typically the determination of validity / invalidity of a horizontal direction block. It is a figure explaining an example of the determination method of the vertical direction motion vector of the whole image. It is a figure explaining an example of the determination method of the vertical direction motion vector of the whole image. It is a block diagram which shows the principal part structure of 2 A of horizontal direction motion vector detection parts in 1 A of motion vector detection apparatuses which concern on Embodiment 2 of this invention. It is a block diagram which shows the principal part structure of 4 A of vertical direction motion vector detection parts in 1 A of motion vector detection apparatuses.

Explanation of symbols

  1, 1A motion vector detector, hb0 to hb9 horizontal block, hn0 to hn9 horizontal block projection data, vb0 to vb7 vertical block, vn0 to vn6 vertical block projection data, A (1) to A (8) 1 threshold intersection, α1 first threshold, α2 second threshold, B (1) to B (6) third threshold intersection, α3 third threshold, α4 fourth threshold.

Claims (18)

A motion vector detection device that detects a motion vector between frame images related to a preceding frame and a following frame that are in a time series front-rear relationship,
Edge enhancement means that emphasizes the edge in the vertical direction for each block divided into a plurality of blocks having a constant division width in the vertical direction with respect to a frame image read out by sequentially repeating pixel scanning of the horizontal line in the vertical direction;
Projecting means for projecting in the vertical direction for each block, and generating projection data having a data array for one horizontal line in each of the blocks, with respect to the image whose edges are enhanced by the edge enhancement means;
Maximum value obtaining means for obtaining a maximum value in an array element of post-frame projection data obtained by the projecting means for the rear frame;
A waveform obtained by graphing array element values in the order of the elements of the data array with respect to the previous frame projection data obtained by the projecting means with respect to the previous frame intersects with a straight line where the array element value is a predetermined constant value. Specifying means for specifying the position of the array element of each intersection to be output as intersection information;
Extracting means for extracting a predetermined range of data array centered on the position of the array element at each intersection from the post-frame projection data;
For each data array in the predetermined range extracted by the extraction means, the values of array elements having the same relative position with respect to the position of the array element at each intersection are added, and each block is based on the obtained addition result Adding means for calculating a horizontal motion vector of
Detecting means for detecting a horizontal motion vector of the entire frame image based on the horizontal motion vector for each block calculated by the adding means;
The detection means includes
The block using at least one of the maximum value of the post-frame projection data obtained by the maximum value obtaining unit, the addition result obtained by the adding unit, and the intersection information obtained by the specifying unit. A motion vector detection apparatus for evaluating the reliability of horizontal motion vectors for each. The detection means includes
When performing a reliability evaluation of the horizontal motion vector for each block using the maximum value of the post-frame projection data,
Obtaining the maximum value in all blocks from the maximum value of the post-frame projection data obtained in each of the plurality of blocks, and the ratio below the predetermined ratio with respect to the maximum value in the all blocks The block having the maximum value is an invalid block, and the horizontal motion vector for each block calculated from the invalid block is not used for detection of a horizontal motion vector of the entire frame image. Motion vector detection device. The detection means includes
When performing the reliability evaluation of the horizontal motion vector for each block using the addition result,
A maximum peak value is obtained from the peak values of the addition results obtained in each of the plurality of blocks, and when the maximum peak value is equal to or greater than a predetermined first predetermined value, a predetermined second value is determined. The block having the maximum value less than or equal to a predetermined value is an invalid block, and the horizontal motion vector for each block calculated from the invalid block is not used for detection of the horizontal motion vector of the entire frame image. The motion vector detection device according to claim 1. The detection means includes
When performing the reliability evaluation of the horizontal motion vector for each block using the intersection information, use the information on the number of intersections among the intersection information,
Of the number of intersections obtained in each of the plurality of blocks, the block having the number of intersections equal to or smaller than a predetermined first predetermined value and equal to or larger than a predetermined second predetermined value is regarded as an invalid block, The motion vector detection device according to claim 1, wherein a horizontal motion vector for each block calculated from an invalid block is not used for detection of a horizontal motion vector of the entire frame image. The detection means includes
When performing the reliability evaluation of the horizontal motion vector for each block using the intersection information, use the information on the number of intersections among the intersection information,
A maximum value is obtained from the number of intersections obtained in each of the plurality of blocks, and when the maximum value is equal to or greater than a first predetermined value, a predetermined second predetermined value or less and a predetermined value The block having the number of intersections equal to or greater than a predetermined third predetermined value is regarded as an invalid block, and the horizontal motion vector for each block calculated from the invalid block is a detection of the horizontal motion vector of the entire frame image. The motion vector detection device according to claim 1, wherein the motion vector detection device is not used for the motion vector. The detection means includes
When a distribution range is obtained for the horizontal motion vector for each block calculated from the block determined to be an effective block by the reliability evaluation of the horizontal motion vector for each block, and the distribution range is equal to or greater than a predetermined threshold The motion vector detection device according to claim 2, wherein a horizontal motion vector of the entire frame image is set to zero. The detection means includes
A previous frame horizontal motion vector storing means for storing a horizontal motion vector of the entire frame image of the previous frame;
Of the horizontal motion vectors for each block calculated from the blocks determined to be the effective blocks, the one closest to the horizontal motion vector of the entire frame image of the previous frame is the frame image of the subsequent frame. The motion vector detection device according to claim 6, wherein the motion vector detection device is an entire horizontal motion vector. An image dividing unit that is arranged in a preceding stage of the edge enhancement unit and sets each of a plurality of image areas obtained by dividing the frame image in the vertical direction as the block;
The motion vector detection apparatus according to claim 1, wherein the edge enhancement unit enhances an edge in a vertical direction for each of the plurality of blocks. An image dividing unit that is arranged at a subsequent stage of the edge emphasizing unit and sets each of a plurality of image areas obtained by dividing the frame image whose edges are emphasized by the edge emphasizing unit in the vertical direction as the block; Prepared,
The motion vector detection device according to claim 1, wherein the edge enhancement unit enhances an edge in a vertical direction of the frame image. A motion vector detection device that detects a motion vector between frame images related to a preceding frame and a following frame that are in a time series front-rear relationship,
With respect to a frame image read by sequentially repeating pixel scanning of the horizontal line in the vertical direction, an edge emphasizing unit that emphasizes the edge in the horizontal direction for each of the blocks divided into a plurality of blocks having a constant division width in the horizontal direction;
Projecting means for performing projection in the horizontal direction for each of the blocks and generating projection data having a data array for one vertical line in each of the blocks with respect to an image whose edges are enhanced by the edge enhancement means;
Maximum value obtaining means for obtaining a maximum value in an array element of post-frame projection data obtained by the projecting means for the rear frame;
A waveform obtained by graphing array element values in the order of the elements of the data array with respect to the previous frame projection data obtained by the projecting means with respect to the previous frame intersects with a straight line where the array element value is a predetermined constant value. Specifying means for specifying the position of the array element of each intersection to be output as intersection information;
Extracting means for extracting a predetermined range of data array centered on the position of the array element at each intersection from the post-frame projection data;
For each data array in the predetermined range extracted by the extraction means, the values of array elements having the same relative position with respect to the position of the array element at each intersection are added, and each block is based on the obtained addition result Adding means for calculating a vertical motion vector of
Detecting means for detecting a vertical motion vector of the entire frame image based on the vertical motion vector for each block calculated by the adding means;
The detection means includes
The block using at least one of the maximum value of the post-frame projection data obtained by the maximum value obtaining unit, the addition result obtained by the adding unit, and the intersection information obtained by the specifying unit. A motion vector detection apparatus for evaluating the reliability of vertical motion vectors for each. The detection means includes
When performing a reliability evaluation of the vertical motion vector for each block using the maximum value of the post-frame projection data,
Obtaining the maximum value in all blocks from the maximum value of the post-frame projection data obtained in each of the plurality of blocks, and the ratio below the predetermined ratio with respect to the maximum value in the all blocks The block having the maximum value is an invalid block, and the vertical motion vector for each block calculated from the invalid block is not used for detection of the vertical motion vector of the entire frame image. Motion vector detection device. The detection means includes
When performing the reliability evaluation of the vertical motion vector for each block using the addition result,
A maximum peak value is obtained from the peak values of the addition results obtained in each of the plurality of blocks, and when the maximum peak value is equal to or greater than a predetermined first predetermined value, a predetermined second value is determined. The block having the maximum value below a predetermined value is an invalid block, and the vertical motion vector for each block calculated from the invalid block is not used for detection of the vertical motion vector of the entire frame image. The motion vector detection apparatus according to claim 10. The detection means includes
When performing the reliability evaluation of the vertical motion vector for each block using the intersection information, information on the number of intersections among the intersection information is used.
Of the number of intersections obtained in each of the plurality of blocks, the block having the number of intersections equal to or smaller than a predetermined first predetermined value and equal to or larger than a predetermined second predetermined value is regarded as an invalid block, The motion vector detection device according to claim 10, wherein the vertical motion vector for each block calculated from an invalid block is not used for detection of a vertical motion vector of the entire frame image. The detection means includes
When performing the reliability evaluation of the vertical motion vector for each block using the intersection information, information on the number of intersections among the intersection information is used.
A maximum value is obtained from the number of intersections obtained in each of the plurality of blocks, and when the maximum value is equal to or greater than a first predetermined value, a predetermined second predetermined value or less and a predetermined value The block having the number of intersections equal to or greater than a predetermined third predetermined value is regarded as an invalid block, and the vertical motion vector for each block calculated from the invalid block is detected as the vertical motion vector of the entire frame image. The motion vector detection apparatus according to claim 10, wherein the motion vector detection apparatus is not used. The detection means includes
When a distribution range is obtained for the vertical motion vector for each block calculated from the block determined to be an effective block by the reliability evaluation of the vertical motion vector for each block, and the distribution range is equal to or greater than a predetermined threshold The motion vector detection device according to claim 11, wherein a vertical motion vector of the entire frame image is set to zero. The detection means includes
A previous frame vertical motion vector storage means for storing a vertical motion vector of the entire frame image of the previous frame;
Of the vertical motion vectors for each of the blocks calculated from the block determined to be the effective block, the one closest to the vertical motion vector of the entire frame image of the previous frame is the frame image of the subsequent frame. The motion vector detection device according to claim 15, wherein the motion vector detection device is an entire vertical motion vector. An image dividing unit that is arranged in a preceding stage of the edge enhancement unit and sets each of a plurality of image regions obtained by dividing the frame image in the horizontal direction as the block,
The motion vector detection apparatus according to claim 10, wherein the edge enhancement unit enhances a horizontal edge for each of the plurality of blocks.   An image dividing unit that is arranged at a subsequent stage of the edge enhancing unit and sets each of a plurality of image areas obtained by dividing the frame image in which the edge is enhanced by the edge enhancing unit in the horizontal direction as the block; The motion vector detection device according to claim 10, wherein the edge enhancement unit enhances a horizontal edge of the frame image.

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