JP2006311061A - Scanning line conversion circuit - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a scanning line conversion circuit capable of enhancing an image quality by contriving an interpolated pixel value as a still picture to be usable for an interpolated pixel detected as a moving picture to the utmost extent in motion adaptive IP conversion processing for detecting motion information in the interpolated pixel and selecting an interpolated pixel value in accordance with the motion information. <P>SOLUTION: The scanning line conversion circuit is characterized by including: a means for storing interpolated data in a preceding frame in addition to selection of the interpolated pixel value from in-field interpolation data and inter-fields interpolation data in accordance with the motion information; and an interpolated pixel information generating means that discriminates whether or not a region including the same pixel information around peripheral regions is present between frames, and selects interpolation data in the preceding frame as the interpolated pixel value when it is present. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a scanning line conversion circuit for converting video information by interlaced scanning into video information by sequential scanning. That is, the present invention relates to a video information processing circuit in a television.

  In recent years, as a method of television broadcasting, the study from the conventional analog method to the digital method has started, and as a result of the new technological innovation of digitalization, television broadcasting has become more advanced as an information communication medium, and has made tremendous development Is trying to achieve. In Japan, digitization has already been realized by broadcasting using CS (Communication Satellite) and broadcasting using BS (Broadcasting Satellite). Furthermore, terrestrial digital broadcasting has also started.

  The advantage of digital television broadcasting is that, in the analog system, a 3-channel program can be transmitted in a frequency band corresponding to one channel, and in the digital system, the number of channels can be increased. As a result, new services such as multi-programs (mixed and multi-organized programs) combining news, sports, dramas, etc., and multi-channel broadcasts that broadcast three different programs within one channel are realized.

  Further, digital television broadcasting enables not only video and audio broadcasting but also an integrated broadcasting service to which various data broadcasting is added. Services that add data broadcasting are divided into those that provide multimedia services by adding data information to TV programs, and those that provide independent services that are separate from TV programs. TV viewers, home shopping, various information services, weather forecasts and news that you can watch whenever you want.

  In order to cope with such digital television broadcasts, television broadcast receivers have also evolved, and a thin, large-screen plasma display has appeared, and conventional CRT-type television receivers are also digital televisions. Some of them have high-definition resolution for broadcasting. In these display devices, video display by sequential scanning is performed instead of conventional video display by interlaced scanning for each line. Therefore, when displaying a conventional analog television broadcast, video information obtained by interlaced scanning is converted into video information obtained by sequential scanning (hereinafter referred to as IP (Interlace-Progressive) conversion), and the resolution of the display device is further increased. Video information is converted and displayed (for example, refer to Patent Document 1).

  Here, a conventional IP conversion processing circuit will be briefly described.

  FIG. 6 is a block diagram showing a configuration of a general IP conversion processing circuit.

  101 and 102 are field information storage units for storing input video information in units of fields, and 103 is the field information currently input and output from the field information storage unit (2) 102. It is determined whether the information is moving image information or still image information in units of pixels by looking at the difference from the field information input in the past for one frame period from the field information currently input, and for each obtained pixel The motion information generation unit 104 that determines and outputs the motion at the interpolated pixel from the motion information of the line, 104 is a line information storage unit for storing the input video information in units of lines, and 107 is the input 2 An adder that performs an addition operation of system signals, 108 is a divider that calculates a half value added by the adder 107, and 109 is a motion information generator 103. In response to the output signal, the pixel information input from the field information storage unit (1) 101 in the past of one field period from the currently input field information, and the interpolation pixel output from the divider 108 The interpolation information selection units 105 and 106 that select an average value of pixel values in the upper and lower lines of the position to obtain an interpolation pixel value are input with the pixel information output from the interpolation information selection unit 109, respectively. An input / output speed conversion unit 110 for storing pixel information in units of lines and reading out the stored pixel information at a speed twice that of the input video information is an input / output speed conversion unit (1) 105 and an input / output This is a display information selection unit that switches and outputs pixel information output from the speed conversion unit (2) 106 for each line.

  The operation of the conventional IP conversion processing circuit described above will be described below.

  The input video information by the jump operation is input to the field information storage unit (1) 101 and the line information storage unit 104, and pixel information delayed by one field period and pixel information of one line before can be obtained from each. Here, FIG. 7 shows a state in which video information in an NTSC (National Television System Committee) signal displayed by interlaced scanning is displayed. In the NTSC signal, as shown in (c), one screen is composed of 525 horizontal lines, and the unit of one screen is called a frame. Further, the frame is divided into an odd field expressing the odd line shown in (d) and an even field expressing the even line shown in (e) by interlaced scanning. The video information of 525 lines is expressed by displaying on the screen. That is, the odd field and the even field are in a relationship of interpolating the line information that is lacking. Therefore, returning to FIG. 6 again, the field information storage unit (1) 101 obtains pixel information in the previous field corresponding to the position of the pixel to be interpolated, and the input video information and line information. From the storage unit 104, pixel information on the upper and lower lines of the pixel to be interpolated is obtained. Further, from the input video information and the line information storage unit 104, an average value of pixel information in the upper and lower lines of the pixel to be interpolated is obtained by the adder 107 and the divider 108, and is used as interpolation pixel information at the time of moving image. It is done.

  The pixel information output from the field information storage unit (1) 101 is further delayed by one field period by the field information storage unit (2) 102 and is video information delayed by one frame period from the input video information, that is, Pixel information input in the past of one frame period corresponding to the position of the input pixel is obtained.

  Next, the motion information generation unit 103 will be described.

  FIG. 8 is a block diagram illustrating an example of the motion information generation unit 103.

  In FIG. 8, reference numeral 1031 denotes the field information that is currently input and the field information that is output from the field information storage unit (2) 102 and that is input in the past one frame period from the field information that is currently input. A subtractor for obtaining a difference, 1032 is an absolute value unit for obtaining an absolute value of the difference value obtained by the subtracter 1031, and 1033 is for comparing a value obtained by the absolute value unit 1032 with a preset threshold value. When the value obtained by the absolute value unit 1032 is smaller than the threshold value, it is determined that the pixel is a still image and “0” is output, and the value obtained by the absolute value unit 1032 is larger than the threshold value. In this case, the threshold filter circuit that determines that the pixel is a moving image and outputs “1” if the pixels are equal to each other. Even if you are joined, it is possible to get rid of that impact if it is some variation. Reference numeral 1034 denotes a line motion information storage unit for storing the motion information for each pixel output from the threshold filter circuit 1033 in units of lines, whereby the line motion information storage unit 1034 receives the input video information. It is possible to obtain motion information at a pixel one line before. Reference numeral 1035 denotes a two-input one-output OR element that obtains a logical sum of the motion information output from the threshold filter circuit 1033 and the motion information of the pixel one line before output from the line motion information storage unit 1034. Thus, the motion information at the interpolation pixel is judged and output.

  Returning to FIG. 6 again, in the interpolation information selection unit 109, when the motion information output from the motion information generation unit 103 is “0”, the pixel information output from the field information storage unit (1) 101 is If “1”, the pixel information output from the divider 108 is selected and output as interpolation pixel information.

The input / output speed conversion unit (1) 105 and the input / output speed conversion unit (2) 106 each store the interpolation pixel information output from the interpolation information selection unit 109 and the input video information in units of lines. The pixel information is read out at twice the speed of the input video information, and the display information selection unit 110 outputs the pixel information and the input / output speed conversion unit from the input / output speed conversion unit (1) 105 for each line. (2) The pixel information output from 106 is switched and output.
JP 2002-112204 A

  However, in the conventional IP conversion method described above, the motion information generation unit 103 determines that the motion information at the interpolation pixel is a moving image, and the interpolation information selection unit 109 outputs the pixel output from the divider 108. When information is selected as an interpolated pixel value, the average value of the pixel values located on the upper and lower lines in the same field becomes the interpolated pixel value, so that the vertical spatial frequency is reduced by half and a blurred image There is a problem of becoming. From such a viewpoint, it is preferable to process the image as a still image as much as possible in order to maintain the vertical spatial frequency, and to use the pixel value in the previous field as the interpolation pixel value.

  For such a problem, it is detected whether there is an area having a similar pixel value in the surrounding video information in one frame period, and if there is an area having a similar pixel value, that area The reference position in the previous field is determined from the motion vector obtained on the assumption that the moving object is moving at a uniform speed, and the pixel value at that position is determined. There is also a proposal that uses as an interpolated pixel value.

  In this proposal, the motion at the interpolation pixel is judged by comparing with the video information of one frame period in the past, and in the case of a moving image, the average value of the pixel values located on the upper and lower lines in the same field is determined as the interpolation pixel. In the case of a still image, the conventional IP conversion method using the pixel value in the previous field as an interpolated pixel value is used as it is, and a means for obtaining a motion vector is further provided so that the motion vector can be obtained. The position of the video information in the past one frame period to be referred to and the position of the video information in the previous field are adjusted.

  However, in the method of adjusting the position of the video information in the past one frame period and the position of the video information in the previous field referred to according to the obtained motion vector as described above, the moving object is If it is not moving at a uniform speed, there is a risk that erroneous information will be used as the interpolation pixel value.

  FIG. 9 shows an example in which the character “H” is displayed by moving horizontally from right to left. In other words, if (f) is the display state of the field of interest, (g) and (h) also indicate the display state over the past of one field period. Here, in order to obtain the interpolated pixel value in the region indicated by the diagonal line in (f), the region where the pixel information matches is searched in the video information of one frame period shown in (h). As a result, the region indicated by the diagonal lines in (h) is detected as a matching region. Accordingly, the interpolation pixel value in the region indicated by the diagonal line in (f) is located between the region indicated by the diagonal line in (f) and the region indicated by the diagonal line in (h), (g) Among the video information in the previous field shown in (3), pixel information in the area indicated by the oblique lines is used.

  However, since the character “H” moves at a uniform speed, appropriate interpolation is performed based on video information in the previous field. However, since the background is not moved, If the video information at is used as the interpolation pixel value, incorrect information will be used as the interpolation pixel value.

  The present invention has been made in view of the above problems, and an object of the present invention is to provide a scanning line conversion circuit capable of preventing deterioration in image quality by suppressing a decrease in spatial frequency in the vertical direction.

In a scanning line conversion circuit that receives video information by interlaced scanning, generates interpolated pixel information, and converts it into video information for sequential scanning.
According to the first aspect of the present invention, the input video information by the interlaced scanning can be stored in a field unit over a plurality of field periods, and the input video information by the interlaced scanning and / or the Motion information generating means for determining the presence / absence of motion for each pixel by obtaining an inter-frame difference signal from the video information stored in the video information storage means, and generating motion information for the interpolated pixel from the determination result; From the video information obtained by interlaced scanning and / or from the video information stored in the video information storage means, an area of video information input in the past for one frame period in which pixel information matches for each predetermined area is obtained. The motion detection means for outputting the position information of the area and the input video information by the interlaced scanning or the video information storage means. In the image information, the inter-field interpolation pixel information generating means for generating the intra-field interpolation pixel information from the pixel information around the interpolation pixel and the interpolation pixel information output from the interpolation pixel information selection means (to be described later) Based on the information output from the interpolation pixel information storage means that can be stored over the field period, and the motion information generation means and the motion detection means, the pixel information generated by the intra-field interpolation pixel information generation means or Interpolation pixel information selection means for selecting either pixel information stored in the video information storage means or pixel information stored in the interpolation pixel information storage means and outputting the selected pixel information as interpolation pixel information. It is what. As a result, in addition to selecting the interpolation pixel value from the interpolation pixel value generated from the pixel information in the field including the interpolation pixel and the pixel value in the previous field as in the conventional IP conversion method, in the past of one frame period When it is possible to select from the interpolated pixel values used, it is detected whether there is no region where the pixel information matches in the video information input in the past of one frame period, and there is no matching region In the conventional method, the interpolation pixel value is selected from the interpolation pixel value generated from the pixel information in the field including the interpolation pixel in accordance with the motion information and the pixel value in the previous field. The interpolated pixel value used in the past in the frame period is selected, and even if the motion information at the interpolated pixel is determined to be a moving image, it is a still image in the past. If the determined information, without reducing the vertical spatial frequency, it is possible to generate an interpolation pixel information.

  According to a second aspect of the present invention, when the motion detection means according to the first aspect obtains an area of video information input in the past for one frame period in which pixel information matches for each predetermined area, Difference information is obtained by accumulating inter-frame difference signals for each pixel in the area, and an area in the video information input in the past for one frame period in which the difference information is minimum is detected. Further, difference information in that area is detected. Is compared with a predetermined threshold value, and when the difference information in the area is smaller than the predetermined threshold value, it is determined that they match. As a result, when determining a region in the video information input in the past for one frame period in which pixel information matches for each predetermined region, even if there is no region that completely matches the pixel information, close pixel information Even if there are irregular pixel value fluctuations such as noise, it is possible to eliminate some errors, and use the interpolated pixel values used in the past of one frame period to Interpolated pixel information can be generated.

  The invention described in claim 3 is a video information storage means capable of storing the inputted video information by the interlaced scanning over a plurality of field periods in a field unit, and the inputted video information by the interlaced scanning and / or Motion information generating means for obtaining an inter-frame difference signal from the video information stored in the video information storage means to determine the presence / absence of motion for each pixel, and generating motion information at the interpolated pixel from the determination result; Difference information is obtained by accumulating inter-frame difference signals for each pixel in a predetermined region for each predetermined region from the image information obtained by the interlaced scanning and / or the image information stored in the image information storage unit. , Detecting a region in the video information input in the past for one frame period in which the difference information is minimum, and obtaining the position information and difference information of the region In-field interpolation pixel for generating intra-field interpolation pixel information from pixel information around the interpolation pixel in the input motion information by the interlaced scanning or the video information stored in the video information storage means Information generation means; interpolation pixel information storage means capable of storing interpolation pixel information output from an interpolation pixel information selection means (to be described later) over a plurality of field periods in field units; and difference information output from the motion detection means Pixel information mixing means for mixing and outputting the pixel information generated by the intra-field interpolation pixel information generation means and the pixel information stored in the interpolation pixel information storage means, and the motion information generation means Pixel information stored in the video information storage means or the pixel information mixing means based on information output from It is characterized in that selects one of the pixel information generated and an interpolation pixel information selecting means for outputting as the interpolation pixel information by. Thus, when obtaining a region of video information input in the past for one frame period in which pixel information matches for each predetermined region, pixel information that is close even when there is no region that completely matches pixel information. An area to be obtained is obtained, and new interpolation pixel information is generated using the interpolation pixel value used in the area, and the opportunity to use the interpolation pixel value used in the past of one frame period increases. It becomes. Furthermore, by mixing and using pixel information generated from pixel information around the interpolated pixels according to the difference information and interpolated pixel information used in the past of one frame period, in the past of one frame period in a region that does not completely match The inaccuracy of the interpolation pixel information due to the use of the used interpolation pixel information is alleviated.

  According to a fourth aspect of the present invention, the motion detecting means according to any one of the first to third aspects further comprises a mask means for ignoring a preset signal line state among the obtained inter-frame difference signals. And the result obtained by the masking means is used as a final inter-frame difference signal. As a result, even if there are irregular pixel value fluctuations such as noise, some errors can be eliminated by applying a simple configuration.

In a video information processing circuit for converting video information by interlaced scanning into video information of sequential scanning,
According to the configuration shown in the first embodiment, as in the conventional IP conversion method, the interpolation pixel value generated from the pixel values located on the upper and lower lines in the same field and the pixel value in the previous field are newly added. In addition to selecting the interpolated pixel value to be generated, means for storing interpolated pixel information used in the past of one frame period over a plurality of field periods is provided, and video information input in the past of one frame period By providing a means for detecting whether or not there is a region in which pixel information matches, it is possible to select from the interpolated pixel values used in the past of one frame period, so that pixels in the video information input in the past of one frame period can be selected. Interpolated pixel information for newly generating interpolated pixel information used in the past of one frame period when there is a region where the information matches For example, even if it is determined that the motion information at the interpolation pixel is a moving image, if the information is determined as a still image in the past, the interpolation pixel can be used without lowering the spatial frequency in the vertical direction. Information can be generated.

  Further, according to the configuration shown in the second embodiment, when it is determined that the motion at the interpolation pixel is a still image, the pixel information in the previous field is output as the interpolation pixel information, and the motion at the interpolation pixel is When it is determined that the image is a moving image, it is further determined whether or not there is a region where the pixel information matches the video information input in the past of one frame period, and the pixel information is included in the video information input in the past of one frame period. If there is no matching area, the pixel value generated from the pixel information in the field including the interpolation pixel is used. If there is a matching area, the interpolation pixel value generated in the past of one frame period is used. When there is a region having pixel information that is close but not present, the pixel value generated from the pixel information in the field including the interpolation pixel and the interpolation pixel value generated in the past of one frame period are mixed. The pixel information generated by the above is output as new interpolated pixel information, so that even if there is no region where the pixel information matches the video information input in the past for one frame period, there is a region having close pixel information Then, it becomes possible to generate interpolation pixel information using the interpolation pixel value used in the past of one frame period, and use the interpolation pixel value used in the past of one frame period in which the pixel information does not match. As a result, the inaccuracy of the newly generated interpolated pixel information is compensated.

  Embodiments of the present invention will be described below in detail with reference to the drawings.

(First embodiment)
FIG. 1 is a block diagram showing a configuration of an IP conversion processing circuit as an embodiment of the present invention.

  In FIG. 1, reference numerals 111 and 112 denote field interpolation information storage units for storing interpolation information output from the interpolation information selection unit 109 in units of fields, and 113 is configured by a conventional method for obtaining a motion vector such as a block matching method. The block coincidence detecting unit compares the input video information with the video information input from the field information storage unit (2) 102 in the past of one frame period from the input video information. Thus, it is detected whether there is no region having the same pixel information in the peripheral region in the video information input in the past for one frame period for each predetermined region of the input video information. If there is a matching area, the matching information indicating that there is a matching area is output, and the input video information area And outputs the position information of the detected one frame period area of the image information input in the past it was. Reference numeral 114 denotes the match information output from the block match detection unit 113, which is expressed by 1 bit indicating whether or not there is a matching area, and the motion of the interpolated pixel output from the motion information generation 103, which is also expressed by 1 bit. A field motion information storage unit that stores information in field units. Reference numeral 109 denotes the interpolation information selection unit described in the conventional IP conversion processing circuit shown in FIG. 6, but here the pixel information output from the field information storage unit (2) 102 and the pixel output from the divider 108 In addition to the information, pixel information output from the field interpolation information storage unit (2) 112 is input, and one of these three pieces of pixel information is selected according to the coincidence information and the motion information output from the field motion information storage unit 114. Output as interpolation pixel information. Other constituent factors are the same as those described as the conventional IP conversion processing circuit shown in FIG.

  Next, the operation of the IP conversion processing circuit according to the present invention having the configuration described above will be described. Here, in the embodiment shown in FIG. 1, video information in n + 1 field is input, video information in n fields is output from the field information storage unit (1) 101, and field information storage unit (2 ) 102 outputs video information in the n-1 field.

  The motion information generation unit 103 obtains and outputs motion information in the n + 1 field from the input video information in the n + 1 field and the video information in the n-1 field output from the field information storage unit (2) 102. Is done. Similarly, the input video information in the n + 1 field and the video information in the n−1 field output from the field information storage unit (2) 102 are input to the block coincidence detection unit 113 and are determined in advance. With respect to the video information in the n + 1 field input in units of areas, the video information in the n-1 field output from the field information storage unit (2) 102 is searched for a region having the same pixel information. In some cases, the coincidence information in that area is set to “1”, and in the absence, the coincidence information in that area is set to “0” and output for each pixel. The motion information output from the motion information generation unit 103 and the match information output from the block match detection unit 113 are stored in the field motion information storage unit 114 and output from the field motion information storage unit 114 with a delay of one field period. Will be. That is, the field motion information storage unit 114 outputs motion information and coincidence information in n fields.

  Also, the pixel information in the n−1 field output from the field information storage unit (2) 102 is input to the interpolation information selection unit 109 as pixel information input in the past of one field period from the field to be interpolated. In addition, in order to obtain the average value of the pixel values in the upper and lower lines of the interpolated pixel position from the divider 108, the n information output from the field information storage unit (1) 101 is sent to the line information storage unit 104 and the adder 107. Pixel information is input, and interpolation information selection unit 109 outputs interpolation pixel information in n fields. The interpolated pixel information in n fields output from the interpolation information selection unit 109 is input to the input / output speed conversion unit (1) 105, and the input / output speed conversion unit (2) 106 is supplied to the field information storage unit (1). The pixel information in the n field output from 101 is input. The pixel information input to the input / output speed conversion unit (1) 105 and the input / output speed conversion unit (2) 106 is the video information input as described in the conventional IP conversion processing circuit shown in FIG. The pixel information read out from the input / output speed conversion unit (1) 105 and the pixel information output from the input / output speed conversion unit (2) 106 for each line by the display information selection unit 110. Are switched and output.

  The interpolation pixel information output from the interpolation information selection unit 109 is simultaneously stored in the field interpolation information storage unit (1) 111, and the interpolation pixel information stored in the field interpolation information storage unit (1) 111 is the block match detection unit. When it is detected in 113 that there is a region that matches the video information input in the past for one frame period, the interpolation pixel information in the matching region is read and stored in the field interpolation information storage unit (2) 112. Is done.

  FIG. 2 shows a state when the block coincidence detecting unit 113 detects an area that matches the video information input in the past of one frame period. In FIG. 2, (a) shows the display state of the field of interest, and (b) shows the display state in the past of that one frame period. Here, when attention is paid to a rectangular area indicated by a diagonal line in (a) with the coordinates located in the upper right corner being “X” in the vertical direction and “Y” in the horizontal direction, the attention shown in (a) A rectangular area having the same pixel information as that of the existing rectangular area exists in an area indicated by a diagonal line in (b) where the coordinates located in the upper right corner are “X + ΔX” in the vertical direction and “Y + ΔY” in the horizontal direction. Is shown.

  Returning to FIG. 1 again, when there is an area that matches the video information input in the past for one frame period in the block match detection unit 113, the interpolation pixel information stored in the field interpolation information storage unit (1) 111 is displayed. As address information for reading, the address information of the rectangular area located at the upper right of the coordinates of (X + ΔX, Y + ΔY) is output, and at the same time, the interpolation information output from the field interpolation information storage unit (1) 111 is used as the field interpolation information storage unit (2) Output address information of a rectangular area in which the coordinates of (X, Y) are located at the upper right as address information for writing to 112. As a result, from the field interpolation information storage unit (1) 111, the interpolation pixel information in the n-1 field in which the coordinates of (X + ΔX, Y + ΔY) are located on the upper right is output for the pixels corresponding to the rectangular area, and the field interpolation information The coordinates (X, Y) of the storage unit (2) 112 are written in the rectangular area located on the upper right. Further, the stored interpolation pixel information is read from the field interpolation information storage unit (2) 112 as the interpolation pixel information in the n-2 field, and is input to the interpolation information selection unit 109.

  In the interpolation information selection unit 109, the pixel information in the n-1 field output from the field information storage unit (2) 102, the average value of the pixel values in the upper and lower lines of the interpolation pixel position output from the divider 108, Further, the n-field interpolated pixel information in the n-2 field output from the field interpolation information storage unit (2) 112 described above is determined in accordance with the motion information output from the field motion information storage unit 114 and the n field. The interpolation pixel value at is determined.

  FIG. 3 shows how the interpolation information selection unit 109 determines interpolation pixel information in n fields. That is, in the interpolation information selection unit 109, when the matching information output from the field motion information storage unit 114 is “1” and there is an area that matches the video information input in the past of one frame period, the information storage unit 114 The interpolated pixel information in the n-2 field that is always output from the field interpolation information storage unit (2) 112 is selected regardless of the output motion information, and the match information output from the field motion information storage unit 114 is “0”. If there is no region that matches the video information input in the past for one frame period, the motion information output from the field motion information storage unit 114 is used in the case of a moving image as in the conventional IP conversion method. Is the average value of the pixel values located on the upper and lower lines in the same field as the interpolated pixel value. In the case of a still image, the pixel value in the previous field is the interpolated pixel value. Forces. That is, when the motion information output from the field motion information storage unit 114 is “1”, the pixel information generated in the field including the interpolation pixel output from the divider 108 is selected, and when the motion information is “0”. Selects pixel information in the n-1 field output from the field information storage unit (2) 102 and outputs it as an interpolated pixel value in the n field.

  According to the configuration described above, the interpolation pixel newly generated from the interpolation pixel value generated from the pixel values located on the upper and lower lines in the same field and the pixel value in the previous field as in the conventional IP conversion method. In addition to selecting a value, there is provided means for storing interpolated pixel information used in the past of one frame period over a plurality of field periods, and further, in the video information input in the past of one frame period, the pixel information By providing means for detecting whether there is no matching area, it is possible to select from interpolated pixel values used in the past of one frame period. Thus, when there is no region where the pixel information matches in the video information input in the past of one frame period, the interpolation pixel generated from the pixel values located on the upper and lower lines in the same field according to the motion information as before The interpolation pixel value to be newly generated by selecting one of the newly generated interpolation pixel values from the value and the pixel value in the previous field, and if there is a matching area, the interpolation used in the past of one frame period The pixel information is used as interpolation pixel information to be newly generated as it is. For example, if the motion information at the interpolation pixel is determined to be a moving image even if it is determined to be a moving image in the past, the vertical information Interpolated pixel information can be generated without reducing the spatial frequency.

  In this example, the motion information generation unit 103 and the block coincidence detection unit 113 are described separately for the purpose of explaining the role of each function in an easy-to-understand manner. Since the motion information is obtained from the inter-frame difference signal for each pixel in the same manner as described above, the motion information generation unit 103 and the block coincidence detection unit 113 are combined into one, for example, the motion at the interpolation pixel from the block coincidence detection unit 113 Even if the information is output, it is not different from the intention of the present invention.

  Further, the block coincidence detection unit 113 determines whether there is a region that matches the video information input in the past for one frame period. By providing means for masking several bits, or as described in the second embodiment, the difference information is obtained by accumulating inter-frame difference signals for each pixel in the area, and the difference information is minimized. An area is detected, the difference information in the area is compared with a predetermined threshold value, and if the difference information in the area is smaller than the predetermined threshold value, it is determined that they match. By providing a means, it is possible to obtain a region having close pixel information as a region where the pixel information matches if there is no region where the pixel information completely matches. , And the do not vary with the intention of the present invention as well, even when taken such means.

(Second embodiment)
In the first embodiment, in addition to selecting a newly generated interpolation pixel value from the interpolation pixel value generated in the field including the interpolation pixel and the pixel value in the previous field as in the conventional IP conversion method, one frame is selected. Provided means for storing interpolated pixel information used in the past in a plurality of field periods, and whether or not there is a region where the pixel information coincides in the video information input in the past in one frame period A description has been given of means that can be selected from interpolated pixel information used in the past of one frame period by providing means for detecting. Further, even when there is no region where the pixel information completely matches with the video information input in the past of one frame period, by providing means for masking the lower-order bits of the inter-frame difference signal for each pixel, or the region The difference information is obtained by accumulating the inter-frame difference signal for each pixel in the image, the area where the difference information is minimum is detected, and the difference information in the area is compared with a predetermined threshold value. And by providing means for determining that the difference information in the area matches when the difference information is smaller than a predetermined threshold value, the area having close pixel information is obtained as the area where the pixel information matches. The means to do was also explained.

  That is, according to the means described in the first embodiment, even if the pixel information includes some fluctuation of the pixel value such as noise, the means for masking the lower-order bits of the inter-frame difference signal for each pixel. Alternatively, by providing means for comparing the difference information with a predetermined threshold value, it is possible to eliminate the influence, but interpolation that newly generates an interpolated pixel value used in the past of one frame period. The condition to be used as the pixel value is a case where there is a region where the pixel information coincides with the video information input in the past of one frame period in a state in which some variation factors of the pixel value such as noise are removed.

  In this example, even if there is no region where the pixel information matches in the video information input in the past for one frame period, if there is a region having similar pixel information, the interpolated pixel value used in the past for one frame period is used. A means for newly generating interpolation pixel information will be described.

  FIG. 4 is a block diagram showing a configuration example of the IP conversion processing circuit in the present embodiment.

  In FIG. 4, reference numeral 113 denotes a block matching detection unit described in the IP conversion processing circuit in the first embodiment shown in FIG. 1, but instead of outputting matching information indicating that there is a matching area, In this example, difference information obtained by accumulating inter-frame difference signals for each pixel within a predetermined range is output as 8-bit information. 114 stores the difference information expressed by 8 bits output from the block match detection unit 113 and the motion information of the interpolation pixel expressed by 1 bit output from the motion information generation unit 103 in units of fields. It is a field motion information storage unit. 115 mixes the pixel information output from the field interpolation information storage unit (2) 112 and the pixel information output from the divider 108 in accordance with the 8-bit difference information output from the field motion information storage unit 114. It is an interpolation information mixing unit to output. Reference numeral 109 denotes an interpolation information selection unit described in the conventional IP conversion processing circuit shown in FIG. 6. Here, the interpolation information selection unit outputs from the field information storage unit (2) 102 according to the motion information output from the field motion information storage unit 114. The pixel information to be output and the pixel information output from the interpolation information selection unit 115 are selected and output as interpolation pixel information. Other constituent factors are the same as those described in the conventional IP conversion processing circuit shown in FIG. 6 and the IP conversion processing circuit as the first embodiment shown in FIG.

  Next, the operation of the IP conversion processing circuit according to the present invention having the configuration described above will be described.

  From the block coincidence detection unit 113, the position information about the input video information area and the position information about the video information area inputted in the past for one frame period in which the coincidence of the video information is detected are output. As described above, difference information expressed in 8 bits obtained by accumulating inter-frame difference signals for each pixel within a predetermined range is output. In the interpolation information mixing unit 115, pixel information output from the field interpolation information storage unit (2) 112 and pixel information output from the divider 108 according to the 8-bit difference information generated by the block match detection unit 113. Will be mixed and output. In this example, the difference information output from the block match detection unit 113 is temporarily stored in the field motion information storage unit 114, and the difference information delayed by one field period is input to the interpolation information mixing unit 115. . As described in the first embodiment, the interpolation pixel information output from the interpolation information selection unit 109 written in the field interpolation information storage unit (1) 111 is the position information (X + ΔX, Y + ΔY) and simultaneously written in the field interpolation information storage unit (2) 112 according to the position information (X, Y) output from the block coincidence detection unit 113. As a result, the interpolated pixel information generated in the past of one frame period is read from the field interpolation information storage unit (2) 112.

  FIG. 5 shows the pixel information output from the field interpolation information storage unit (2) 112 and the divider 108 in accordance with the 8-bit difference information output from the field motion information storage unit 114 in the interpolation information mixing unit 115. It shows how the output pixel information is mixed.

  In this example, since the difference information generated by the block match detection unit 113 is expressed by 8 bits, the maximum difference information that can be expressed is “255”, and the inter-frame difference signal is accumulated beyond that. The difference information is output as “255” which is the maximum value.

  When the difference information generated by the block coincidence detection unit 113 is “0”, there is a region where the pixel information matches the video information input in the past of one frame period. In this case, interpolation is performed. The information mixing unit 115 outputs the interpolation pixel information generated in the past of one frame period output from the field interpolation information storage unit (2) 112. When the difference information is “255”, there is no region where the pixel information is close to the video information input in the past of one frame period. In this case, the interpolation information mixing unit 115 receives the information from the divider 108. Pixel information generated in the field including the output interpolation pixel is output. When the difference information is in the range from “1” to “254”, there is a region where the pixel information is close to the video information input in the past of one frame period. In this case, the field interpolation information storage unit (2) The interpolated pixel information generated in the past for one frame period output from 112 and the pixel information generated in the field including the interpolated pixel output from the divider 108 are mixed and output in accordance with a preset mixing ratio. Will be. Here, the mixing ratio in the range where the difference information is “1” to “254” is one in which one of them changes linearly in the range of 0% to 100%, or in the range of 0% to 100%. It changes in a stepwise manner, or changes with a specific weight on either the pixel information generated in the field including the interpolation pixel or the interpolation pixel information generated in the past of one frame period, Several settings are conceivable, but no matter what the mixing ratio is selected, it does not change from the intention of the present invention.

  Returning to FIG. 4 again, the interpolated pixel information selection unit 109 performs the pixel information output from the field information storage unit (2) 102 and the interpolation information mixing unit 115 according to the motion information output from the field motion information storage unit 114. Any pixel information to be output is selected and output as interpolation pixel information. That is, when the motion information output from the field motion information storage unit 114 is “0”, there is no motion at the interpolated pixel, and thus the pixel information in the previous field output from the field information storage unit (2) 102. Is output as interpolation pixel information, and when it is “1”, the pixel information output from the interpolation information mixing unit 115, that is, when there is no region where the pixel information matches in the video information input in the past for one frame period. The pixel information generated in the field including the interpolated pixel output from the divider 108 is generated in the past of one frame period output from the field interpolation information storage unit (2) 112 when there is a matching area. Interpolated pixel information in the field including the interpolated pixel output from the divider 108 when there is no matching area but there is an area having close pixel information. Outputting pixel information generated by mixing the generated pixel information and interpolation pixel information generated in the past of one frame period output from the field interpolation information storage unit (2) 112 as new interpolation pixel information; Become.

  According to the configuration described above, even when there is no region in which pixel information matches in the video information input in the past of one frame period, if there is a region having close pixel information, the interpolation used in the past of one frame period Interpolation pixel information is generated using the pixel value. At this time, the interpolation pixel value used in the past for one frame period is not simply used as interpolation pixel information to be newly generated. Newly generated by using interpolated pixel values used in the past of one frame period in which pixel information does not match by using pixel information generated by mixing with pixel values generated from pixel information in a field including Inaccuracy of the interpolated pixel information is compensated.

  In this example, as described in the first embodiment, the motion information generation unit 103 and the block coincidence detection unit 113 are described separately for the purpose of easily explaining the role of each function. Similarly to the block coincidence detection unit 113, the motion information generation unit 103 obtains the motion information by obtaining an inter-frame difference signal for each pixel. Therefore, the motion information generation unit 103 and the block coincidence detection unit 113 are combined into one. In summary, for example, outputting the motion information at the interpolation pixel from the block coincidence detection unit 113 is not different from the intended one of the present invention.

  Further, by providing means for masking the lower-order bits of the inter-frame difference signal for each pixel obtained by the block coincidence detection unit 113, or difference information obtained by the block coincidence detection unit 113 and a predetermined threshold value There was an irregular variation in pixel values such as noise by providing a means for determining that the difference information in that region is consistent when the difference information is smaller than a predetermined threshold. However, it is possible to eliminate some errors, and even if such a measure is taken, it is not different from the intention of the present invention.

The block diagram which showed the structure of the IP conversion processing circuit in 1st Example of this invention. The schematic diagram which showed a mode that the area | region corresponding to the video information input in the past for one frame period was detected in the block coincidence detection part in 1st Example of this invention. The schematic diagram which shows a mode that the interpolation pixel information is selected in the interpolation information selection part in 1st Example of this invention. The block diagram which showed the structure of the IP conversion processing circuit in 2nd Example of this invention. In the interpolation information mixing unit according to the second embodiment of the present invention, the pixel in the field including the interpolation pixel information generated in the past of one frame period and the interpolation pixel according to the difference information generated in the block match detection unit Schematic showing how the interpolated pixel information generated from the information is mixed Block diagram showing the configuration of a conventional IP conversion processing circuit Schematic diagram showing how to display interlaced scanning video information Block diagram showing the configuration of a conventional motion detection generator Schematic diagram showing an example of the display screen

Explanation of symbols

101, 102 Field information storage unit 103 Motion information generation unit 104 Line information storage unit 105, 106 Input / output speed conversion unit 107 Adder 108 Divider 109 Interpolation information selection unit 110 Display information selection unit 111, 112 Field interpolation information storage unit 113 Block match detection unit 114 Field motion information storage unit 115 Interpolation information mixing unit 1031 Subtractor 1032 Absolute value unit 1033 Threshold filter circuit 1034 Line motion information storage unit 1035 OR element

Claims (4)

In a scanning line conversion circuit that receives video information by interlaced scanning, generates interpolated pixel information, and converts it into video information for sequential scanning.
Video information storage means capable of storing the input video information by the interlaced scanning over a plurality of field periods in a field unit;
From the input video information by the interlaced scanning and / or the video information stored in the video information storage means, an inter-frame difference signal is obtained to determine the presence or absence of motion for each pixel, and the motion information at the interpolated pixel is determined from the determination result. Motion information generating means for generating
From the inputted video information by the interlaced scanning and / or the video information stored in the video information storage means, the video information inputted in the past for one frame period in which the pixel information matches every predetermined region. Motion detection means for obtaining an area and outputting position information of the area;
In-field interpolated pixel information generating means for generating intra-field interpolated pixel information from pixel information around the interpolated pixels in the input video information by the interlaced scanning or the video information stored in the video information storage means,
Interpolation pixel information storage means capable of storing interpolation pixel information output from an interpolation pixel information selection means, which will be described later, over a plurality of field periods in field units;
Based on the information output from the motion information generation means and the motion detection means, the pixel information generated by the intra-field interpolation pixel information generation means, the pixel information stored in the video information storage means, or the interpolation pixels Interpolation pixel information selection means for selecting any of the pixel information stored in the information storage means and outputting the selected pixel information as interpolation pixel information;
A scanning line conversion circuit comprising:   The motion detection means accumulates inter-frame difference signals for each pixel in the region when obtaining a region of video information input in the past for one frame period in which the pixel information matches for each predetermined region. Thus, the difference information is obtained, the area in the video information input in the past for one frame period in which the difference information is minimum is detected, and the difference information in the area is compared with a predetermined threshold value. 2. The scanning line conversion circuit according to claim 1, wherein the scanning line conversion circuit according to claim 1, wherein the scanning line conversion circuit determines that they match when the difference information in the region is smaller than a predetermined threshold value. In a scanning line conversion circuit that receives video information by interlaced scanning, generates interpolated pixel information, and converts it into video information for sequential scanning.
Video information storage means capable of storing the input video information by the interlaced scanning over a plurality of field periods in a field unit;
From the input video information by the interlaced scanning and / or the video information stored in the video information storage means, an inter-frame difference signal is obtained to determine the presence or absence of motion for each pixel, and the motion information at the interpolated pixel is determined from the determination result. Motion information generating means for generating
The difference is obtained by accumulating inter-frame difference signals for each pixel in a predetermined area from the input video information by the interlaced scanning and / or video information stored in the video information storage means. Motion detection means for obtaining information, detecting a region in the video information input in the past for one frame period in which the difference information is minimum, and outputting position information and difference information of the region;
In-field interpolated pixel information generating means for generating intra-field interpolated pixel information from pixel information around the interpolated pixels in the input video information by the interlaced scanning or the video information stored in the video information storage means,
Interpolation pixel information storage means capable of storing interpolation pixel information output from an interpolation pixel information selection means, which will be described later, over a plurality of field periods in field units;
Based on the difference information output from the motion detection means, the pixel information generated by the interpolated pixel information generation means and the pixel information stored in the interpolation pixel information storage means are mixed and output. Information mixing means;
Based on the information output from the motion information generating means, the pixel information stored in the video information storage means or the pixel information generated by the pixel information mixing means is selected and output as interpolated pixel information. Interpolation pixel information selection means;
A scanning line conversion circuit comprising:   The motion detecting means includes mask means for ignoring a preset signal line state among the obtained inter-frame difference signals, and the result obtained by the mask means is used as a final inter-frame difference signal. The scanning line conversion circuit according to claim 1, wherein: