JP2007158992A - Device, method and program for video signal correction - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To obtain images with moderate enhancement correction added by suppressing excessive correction and reducing a signal-to-noise ratio in image correction such as edge enhancement. <P>SOLUTION: A video signal correction device enhances edges of video signals and has an edge filter 12 for extracting an edge component of a video signal, an amplifier 18 for amplifying the extracted edge component, and an adder 20 for adding the amplified edge component to the original video signal. The device further has a feature quantity extracting part 14 for extracting feature quantity of the video signal, and an amplifying rate deriving part 16 for deriving an amplifying rate corresponding to the feature quantity. In this case, the amplifier amplifies the edge component at an amplifying rate derived from the amplifying rate deriving part. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a video signal correction apparatus, method, and program.

  In general, in a video apparatus, contour correction for enhancing a contour portion is performed as an example of video signal correction in order to sharpen a blurred image. For example, contour correction is realized by extracting a high frequency component (edge component) of a video signal, amplifying it, and adding it to the video signal. That is, it is possible to emphasize the change by performing additional correction on a portion where the brightness of the image changes.

On the other hand, if the contour portion is emphasized uniformly, ringing or the like may occur at the edge of the telop where the contrast is originally clear, which may impair the image quality. Therefore, a contour correction device that restricts contour correction in a portion where additional information such as telop or caption is superimposed (for example, at the bottom of the screen) has been proposed (for example, Patent Document 1).
Japanese Patent No. 3078918

  However, not only at the edge of the telop as described above, but also when the outline portion is emphasized, the change in brightness is so steep that the ringing or the like occurs, and the portion where the outline correction should be restricted is within the entire screen area. Exists. Further, when a high frequency component is amplified for contour correction, noise is amplified together with the high frequency component, and there is a portion where the signal-to-noise ratio deteriorates.

  Accordingly, the present invention has been made in view of the above problems, and an object of the present invention is to suppress excessive correction and reduce the signal-to-noise ratio when correcting a video signal. Another object of the present invention is to provide a new and improved video signal correction apparatus, method and program.

  In order to solve the above problems, according to an aspect of the present invention, an edge filter that extracts an edge component of a video signal, an amplifier that amplifies the extracted edge component, and the amplified edge component as an original video An adder for adding to a signal, and a video signal correction device for enhancing an edge of a video signal, comprising: a feature quantity extraction unit for extracting a feature quantity of the video signal; and an amplification factor corresponding to the feature quantity And an amplification factor deriving unit for deriving the image signal correction device, wherein the amplifier amplifies an edge component with the amplification factor from the amplification factor deriving unit. With such a configuration, it is possible to obtain an image with appropriate enhancement correction according to the atmosphere (feature value) of the image.

  The feature amount extraction unit may detect the feature amount based on a video signal in a predetermined region of the same frame. In such a configuration, the feature amount extraction unit acts to detect the feature amount while suppressing the amount of calculation to a level necessary and sufficient for grasping the image feature.

  The feature amount may represent a degree of change in luminance between pixels constituting the predetermined area of the same frame. In such a configuration, the feature amount acts as a judgment material for detecting whether, for example, a contour portion having a sharp change in luminance is included in the predetermined region.

  The feature amount may be an absolute deviation of luminance of pixels constituting the predetermined area of the same frame. In such a configuration, the feature amount can quantitatively represent the degree of change in luminance between pixels.

  The amplification factor deriving unit may classify the pixels into any of a predetermined number of categories based on the feature amount. With such a configuration, it is possible to perform processing based on the predetermined number of categories instead of feature values that can take a wide range of values.

  The amplification factor deriving unit may derive the amplification factor of the pixel based on a classification to which the pixel belongs. With this configuration, the amplification factor deriving unit can derive an appropriate amplification factor according to the segment to which the pixel belongs by referring to a table in which the segment and the amplification factor correspond one-to-one.

  The predetermined number of classifications includes a classification in which the undulation of luminance of the peripheral pixels is flat, a classification in which the peripheral pixels have the edge component to be emphasized, a classification in which the peripheral pixels include a lot of noise components, and It may be one or more sections selected from a group of sections in which the luminance difference between peripheral pixels is significant.

  The amplification factor of the section in which the luminance unevenness of the peripheral pixels is flat may be 1. In such a configuration, the amplification factor deriving unit operates to maintain the identity of the original feature of the image in a flat portion where the original feature is impaired when the luminance difference between pixels is emphasized.

  The amplification factor of the segment in which the peripheral pixel has the edge component to be emphasized may be higher than the amplification factor of the segment in which the undulation of the luminance of the peripheral pixel is flat. In such a configuration, the amplification factor deriving unit acts to clarify the boundary portion of the image constituting one frame.

  The amplification factor of the segment in which the surrounding pixel includes a lot of noise components is higher than the amplification factor of the segment in which the luminance unevenness of the peripheral pixel is flat, and the peripheral pixel has the edge component to be emphasized It may be lower than the amplification factor of the section. In such a configuration, the amplification factor deriving unit functions to suppress the amplification of the noise component together with the high frequency component of the video signal, and to prevent the deterioration of the video to noise ratio.

  The amplification factor of the segment in which the luminance difference between the peripheral pixels is severe is higher than the amplification factor of the segment in which the undulation of the luminance of the peripheral pixel is flat, and the peripheral pixel has the edge component to be emphasized. It may be lower than the amplification factor of the section. In such a configuration, the amplification factor deriving unit prevents an excessive luminance difference and ringing in the image.

  The amplification factor deriving unit may classify the pixels into the predetermined number of categories based on the normalized feature value after normalizing the feature value. With this configuration, the amplification factor deriving unit can classify pixels uniformly.

  In order to solve the above problems, according to another aspect of the present invention, there is provided a video signal correction method for correcting a video signal by a video signal correction device that emphasizes an edge of the video signal: Extracting an edge component of the video signal; extracting a feature amount of the video signal; deriving an amplification factor corresponding to the feature amount; amplifying the extracted edge component by the amplification factor And a step of adding the amplified edge component to the original video signal. A video signal correction method is provided. With such a configuration, similarly to the video signal correction apparatus, it is possible to obtain an image with appropriate enhancement correction according to the feature amount.

  In order to solve the above problems, according to another aspect of the present invention, there is provided a video signal correction program for realizing edge enhancement of a video signal: a step of extracting an edge component of the video signal into a computer; Extracting a feature amount of the video signal; deriving an amplification factor corresponding to the feature amount; amplifying the extracted edge component by the amplification factor; and based on the amplified edge component And a step of adding to the video signal. A video signal correction method program is provided. With such a configuration, similarly to the video signal correction apparatus, it is possible to obtain an image with appropriate enhancement correction according to the feature amount.

  As described above, according to the present invention, it is possible to provide a video signal correction apparatus, method, and program capable of suppressing excessive correction and reducing a signal-to-noise ratio when correcting a video signal. is there.

  Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings. In the present specification and drawings, components having substantially the same functional configuration are denoted by the same reference numerals, and redundant description is omitted.

  FIG. 9A is an explanatory diagram showing an example of frequency components included in the video signal. The horizontal axis represents frequency and the vertical axis represents amplitude. As shown in FIG. 9A, the video signal is composed of various frequency components from a low frequency component to a high frequency component, and the contour component (edge component) is mainly included as a high frequency component. When such a video signal is simply transmitted or processed, the high-frequency component representing the contour component is attenuated, and the contour portion included in the image may be blurred.

  FIG. 9B is an explanatory diagram showing a state in which high frequency components are intentionally extracted from the video signal. The horizontal axis represents frequency and the vertical axis represents amplitude. When the contour portion is blurred as described above, a signal in the vicinity of a high frequency component (for example, 2M to 3 MHz) of the video signal is extracted using a high pass filter or a band pass filter as shown in FIG. To the video signal. In this way, the boundary portion of the image is clarified (emphasized), and a clear image can be obtained.

  FIG. 10 is a block diagram showing a configuration of an image correction circuit used for correcting the image as described above. The image correction circuit includes an edge filter 62, an amplifier 68, and an adder 70.

  The edge filter 62 extracts edges using, for example, a high-pass filter, the amplifier 68 increases or decreases the output from the edge filter 62, and the adder 70 adds this to the original signal. With the above specific configuration, reliable and consistent contour correction has been performed.

  However, in an actual image, if the correction was made uniformly, the correction was too small or too large, and ringing might occur. Here, ringing will be briefly described with reference to FIG.

  FIG. 11 is an explanatory diagram regarding the occurrence of ringing. FIG. 11A shows a part of the image, where the center is dark and the left and right are bright. FIG. 11B shows the above-described image as a luminance signal, where the level of the dark part is low and the level of the bright part is high. FIG. 11C shows a preshoot 80 and an undershoot 82 added to the luminance signal in order to clarify the luminance boundary. FIG. 11D shows a signal obtained by adding a preshoot 80 and an undershoot 82 to the luminance signal.

  In order to further amplify the edge component of such a signal, the signal needs to pass through an edge filter as described above. However, the edge filter has a delay characteristic, and distortion may occur during signal transmission. Then, due to the delay characteristics and the like, the output from the video signal correction circuit appears as if the preshoot 80 and the undershoot 82 swell as shown in FIG. 11E, and this is called ringing. Yes. The present invention solves the above-described problems by appropriately adjusting the size of the contour component to be emphasized when correcting the contour of an image.

  First, a video signal correction apparatus according to an embodiment of the present invention will be described.

  FIG. 1 is a block diagram showing a configuration of a contour correction circuit according to the present embodiment. The contour correction circuit according to the present embodiment includes an edge filter 12, a feature amount extraction unit 14, an amplification factor derivation unit 16, an amplifier 18, and an adder 20.

  The edge filter 12 receives the video signal, extracts an edge component, and outputs it to the amplifier 18. The edge filter 12 may be composed of a second order differential filter in order to perform the above function.

  FIG. 2 is an explanatory diagram showing an example of a secondary differential filter used for the edge filter 12. The second-order differential filter will be described below.

  The second-order differential filter extracts all edge components included in the image regardless of their directions. As shown in FIG. 2 (a), even if it is composed of the center 6 in the 3 × 3 pixel, the coefficient −1 at the center of each side, and the coefficient −0.5 at each vertex, It may be composed of the center 8, the center of each side, and the -1 coefficient of each vertex.

  An edge component is detected by multiplying the coefficient by the luminance value of each pixel and calculating the sum of the obtained results. For example, the calculation result is almost 0 in a portion where the luminance gradient is small, and the calculation result is a value having a large absolute value in a portion where the luminance gradient is large.

  By performing the edge detection for all the pixels, an edge component having a large luminance gradient can be extracted from the entire image regardless of whether the luminance gradient between the pixels is positive or negative. Even if the above-described detection is performed on the pixels constituting the outermost peripheral portion of the image, pixels in at least one direction (up, down, left, and right) do not exist, and edge components are not correctly detected. Therefore, in such a case, the center value of the secondary differential filter may be varied so that the sum of the coefficients of the secondary differential filter in the pixel region to be used becomes zero.

  The feature amount extraction unit 14 detects a feature amount representing the feature of the image in parallel with the processing of the edge filter 12. The feature amount may be, for example, an absolute deviation of luminance values of pixels included in a predetermined area of the same frame.

  FIG. 3 is an explanatory diagram of the absolute deviation detection method according to the present embodiment. One square means one pixel, and shows a rectangular region having 7 pixels in the horizontal direction and 3 pixels in the vertical direction.

数式１は，上記絶対偏差を算出するための計算式である。Ｖは絶対偏差，ｎは横方向の画素数，ｎは縦方向の画素数，Ｘ_ｉ，ｊは特定の画素，Ｘ_ａｖｅは上記長方形領域に含まれる画素の輝度の平均値を示している。

Formula 1 is a calculation formula for calculating the absolute deviation. V is an absolute deviation, n is the number of pixels in the horizontal direction, n is the number of pixels in the vertical direction, X _{i, j} are specific pixels, and X _ave is an average value of the luminance of the pixels included in the rectangular area.

  As shown in Equation 1, in order to obtain the feature amount of the central pixel of the rectangular area, the average value of the luminance of all 7 × 3 pixels and the absolute value of the difference between the pixels are added. Therefore, the feature amount increases as the undulations of the surrounding pixels increase, and decreases as the undulations decrease. In other words, the feature amount represents the degree of change in luminance between pixels constituting the predetermined area.

  The example in which the feature amount is detected using the rectangular area of 7 × 3 pixels has been described. However, the above-mentioned area is in accordance with the number of pixels of one frame of the video to be displayed and the display purpose so that the above-mentioned feature amount can be detected while suppressing the calculation amount to a degree necessary and sufficient for grasping the image feature. It may be changed. For example, it may be a rectangular region such as 3 × 5, 5 × 7, 5 × 37 × 5, or 19 × 9, or a square region such as 5 × 5, 7 × 7, or 23 × 23.

  Further, in order to detect the feature amount of the pixel of interest, a description has been given by taking a predetermined region where the pixel of interest is located at the center as an example. If the predetermined region is configured so that the pixel of interest is positioned at the lower right vertex portion, the display pixel flows from the upper left to the lower right, so that the feature amount can be detected only from the data read so far.

  The amplification factor deriving unit 16 classifies the pixels into a predetermined number, for example, one of four categories, based on the feature amount of the pixel, in order to derive the amplification factor corresponding to the feature amount. Then, the amplification factor of the pixel is derived according to the division to which the pixel belongs.

  In the classification, the absolute deviation as a feature amount may be used. The absolute deviation is easy to classify because it quantitatively shows the characteristics of the surrounding pixels. Specifically, it can be classified as follows, for example.

  FIG. 4 is a frequency distribution diagram showing a method of classifying each pixel based on the absolute deviation. The horizontal axis represents the normalized absolute deviation of each pixel, and the vertical axis represents the frequency.

  The normalization means that the data is transformed according to a certain rule for easy use. For example, specifically, the maximum absolute deviation among the absolute deviations of all pixels constituting the same frame is set to 100, In addition, this is realized by modifying the absolute deviation of all the pixels so that the absolute deviation ratio between the pixels is maintained. As a result of the normalization, the maximum values of the normalized absolute deviation constituting one frame are all 100, and the processing can be performed uniformly.

  The above sections may be four sections L0, L1, L2, and L3. For example, all the pixels constituting one frame are sequentially arranged from the normalized absolute deviation value from the smallest value to the larger value, L0 is a pixel included in 0 to 5% from the smallest value, and L1 is 5 to 5. A pixel included in 40%, a pixel included in 40 to 85% in L2, and a pixel included in 85 to 100% in L3 can be classified. Such a division of L0 to L3 is expressed as shown in FIG. 4 on the normalized absolute deviation frequency distribution.

  Since the pixels classified in the L0 section have almost no absolute deviation, it is considered that the undulation of the brightness of the peripheral pixels is flat. Therefore, the amplification factor deriving unit 16 may derive the amplification factor so as not to amplify the edge component extracted by the edge filter 12 from each pixel classified into the L0 section. When the amplification is not performed, the amplifier outputs the edge component extracted by the edge filter 12 to the adder 20 as it is (with amplification factor = 1). However, since the edge component is extracted from the image portion determined to be flat, there is a high possibility that the edge component has almost no value. Therefore, even if the adder 20 adds the edge component to the original video signal, the influence on the image is small and the atmosphere of the image can be maintained.

  Since the pixels classified in the L1 section have a small absolute deviation, it is considered that a lot of noise components are included in the surrounding pixels. Therefore, the amplification factor deriving unit 16 may derive an amplification factor higher than the amplification factor of the L0 segment and lower than the amplification factor of the L2 segment, which will be described later, in the L1 segment. With such a configuration, amplification of the noise component can be suppressed and deterioration of the signal-to-noise ratio can be prevented.

  Since the pixels classified into the L2 section have a large absolute deviation, it is considered that the peripheral components have the edge component to be emphasized. Therefore, the amplification factor deriving unit 16 may derive a higher amplification factor in the L2 segment than the amplification factor of the L0 segment.

  Since the pixels classified into the L3 section have a considerably large absolute deviation, it is considered that the luminance difference between peripheral pixels is severe. Therefore, the amplification factor deriving unit 16 may derive an amplification factor higher than the amplification factor of the L0 segment and lower than the amplification factor of the L2 segment in the L3 segment. With such a configuration, generation of excessive luminance difference and ringing can be suppressed.

  The amplifier 18 receives the edge component of the image from the edge filter 12, amplifies the edge component with the amplification factor derived by the amplification factor deriving unit 16, and outputs the amplified edge component to the adder 20. The amplification is performed by using the output of the secondary differential filter as the edge filter 12 and the amplification factor derived by the amplification factor deriving unit 16 based on the classification to which each pixel belongs (for example, 1 ×, 1.2 ×, 1.5 ×, 2 times) may be simply multiplied.

  The adder 20 receives the video signal and the edge component from the amplifier, adds them, and outputs a corrected video signal. In this way, only the high frequency component of the video signal can be adjusted and output.

  FIG. 5 is an explanatory diagram showing an example of an actual image. The image includes a sky 30, a house 32, a grassland 34, a person 36, a car 38, and a tree 40 as subjects.

  Since the sky 30 is flat and has almost no luminance change and no absolute deviation, it is classified as L0. The house 32 and the grassland 34 are classified as L1 because the image quality is rough, the luminance change and the absolute deviation are small. Since the luminance change at the boundary between the person 36 and the car 38 and the sky 30 and the absolute deviation are large, it is classified as L2. Since the luminance change and the absolute deviation at the boundary portion between the tree 40 and the sky 30 are quite large, it is classified as L3.

  The normalized absolute deviation distribution as shown in FIG. 4 is merely an example, but even if the frame is changed and the distribution is derived in a different form, the pixel classification is based on the frequency distribution, so the number of pixels in each division is The same correction can be made for each frame. That is, if the absolute deviation partly protrudes and a large pixel is included in the frame, the frequency distribution is entirely biased to the left of the drawing, but the normalized absolute deviation value of each pixel is Based on the relative classification, any pixel is not classified as L0.

  In addition, the predetermined number of divisions is four divisions, and the amplification degree according to the divisions is specifically shown. However, these may be automatically or artificially changed according to the characteristics of the device used and the video to be displayed. Examples of the video to be displayed include terrestrial, HD (High Definition), and PC (Personal Computer) video. For example, when the present embodiment is applied to HD, HD can reproduce high-definition video. Therefore, if the L1 section is set widely, the characteristics cannot be utilized. On the other hand, the L1 section may be set widely for terrestrial waves that easily contain noise components.

  In the video signal correction apparatus as described above, since the original image to be corrected is subjected to image analysis by the edge filter 12 and the feature amount extraction unit 14, the result is obtained with a slight delay from the original image. Therefore, the amplification factor (correction amount) of an arbitrary frame image is applied to the next frame image. Hereinafter, such deviation of the correction target will be described in detail.

  FIG. 6 is an explanatory diagram showing timing at which the amplification factor derived by the amplification factor deriving unit according to the present embodiment is applied. 6A is a circular image of a certain frame, and FIG. 6B is an image of a triangular frame after one frame of FIG. 6A. In other words, this means that there has been a scene change from FIG. 6 (a) to FIG. 6 (b). FIG. 6C shows edge components extracted by the edge filter 12 from the image of FIG.

  On the other hand, the amplification factor deriving unit 16 must accumulate data for one frame in order to normalize the absolute deviation, and a frame to which the amplification factor actually derived derives the amplification factor. This is the one frame after the frame used for the purpose.

  FIG. 6D shows the state, and FIG. 6D shows the triangular edge component 50 extracted by the edge filter 12 from the image of FIG. 6B and the amplification factor deriving unit. 16 shows the positional relationship of the amplification pixel region 52 from which the amplification factor that amplifies the edge component is derived. That is, the triangular edge component 50 emphasizes only the vertex portions where the circular image and the triangular image are in contact with each other.

  However, the above-mentioned adverse effects are caused only by one frame where the scene is switched. Furthermore, a frame buffer can be provided to completely eliminate the above-mentioned adverse effects. That is, a frame buffer can be provided in parallel with the edge filter 12 between the edge filter 12 and the amplifier 18 of FIG. 1 and / or on the input side of the adder 20. With this configuration, the original image to be output is temporarily held in the frame buffer, and the original video and the frame to which the amplification factor derived by the amplification factor deriving unit 16 is applied can be added by the adder 20. Thus, it is possible to avoid the problem that the correction target is shifted as described above.

  Next, a video signal correction method using the above-described video signal correction apparatus will be described.

  FIG. 7 is a flowchart showing the flow of the video signal correct method according to the present embodiment. In the video signal correcting method, the edge filter 12 of the video signal correction apparatus first extracts an edge component contained in the input video signal (S62).

  Subsequently, the feature quantity extraction unit 14 of the video signal correction apparatus extracts the feature quantity of the video signal from the input video signal (S64). Then, the amplification factor deriving unit 16 derives the amplification factor of the edge component from the feature amount (S66). Next, the amplifier 18 amplifies the edge component using the amplification factor (S68), and finally, the adder 20 adds the amplified edge component to the original video signal and outputs it (S70). . Note that the step of detecting the edge component (S62) is not limited to the order of processing shown in FIG. 7, and may be before the step of amplifying the edge component (S68).

  Also provided are a program for causing a video signal correction apparatus to perform the video signal correction method as described above, and a storage medium storing the program.

  As mentioned above, although preferred embodiment of this invention was described referring an accompanying drawing, it cannot be overemphasized that this invention is not limited to the example which concerns. It will be apparent to those skilled in the art that various changes and modifications can be made within the scope of the claims, and these are naturally within the technical scope of the present invention. Understood.

  For example, the feature amount is not limited to the absolute deviation of the luminance values of pixels included in a predetermined area of the same frame, and may be obtained from a frequency distribution. FIG. 8 is an explanatory diagram showing a method of extracting feature amounts according to another embodiment. The horizontal axis represents frequency and the vertical axis represents frequency.

  According to the frequency frequency distribution of FIG. 8, this video signal contains many high frequency components in addition to low frequency components, and has two raised portions on the frequency distribution diagram. That is, since the high frequency component constitutes an edge component, the signal has a high luminance gradient. Therefore, it is possible to obtain the feature amount based on the degree of such a raised portion. Similarly, the feature amount can be obtained based on the luminance frequency distribution.

  Note that each step in the video signal correction method of the present specification does not necessarily have to be processed in time series in the order described in the flowchart, but is performed in parallel or individually (for example, parallel processing or object processing). May be included.

  The present invention is applicable to a video signal correction apparatus, method, and program.

It is the block diagram which showed the structure of the outline correction circuit by this embodiment. It is explanatory drawing which showed an example of the filter used as an edge filter. It is explanatory drawing of the detection method of the said absolute deviation by this embodiment. It is a frequency distribution diagram showing a classification method of each pixel based on absolute deviation. It is explanatory drawing which showed an example of the actual image. It is explanatory drawing which showed the timing when the amplification factor derived | led-out by the amplification factor deriving part by this embodiment is applied. 5 is a flowchart showing a flow of a video signal correction method according to the present embodiment. It is explanatory drawing which shows the method of extracting the feature-value by other this embodiment. It is explanatory drawing which showed an example of the frequency component contained in a video signal. It is explanatory drawing which shows a mode that the high frequency component was extracted from the video signal. It is the block diagram which showed the structure of the image correction circuit used in order to correct | amend the conventional image. It is explanatory drawing about generation | occurrence | production of ringing.

Explanation of symbols

12, 62 Edge filter 14 Feature amount extraction unit 16 Amplification factor derivation unit 18, 68 Amplifier 20, 70 Adder 30 Sky 32 House 34 Grassland 36 People 38 Car 40 Tree 50 Triangle edge component 52 Amplification pixel area 80 Preshoot 82 Undershoot

Claims (14)

An edge filter that extracts an edge component of a video signal, an amplifier that amplifies the extracted edge component, and an adder that adds the amplified edge component to the original video signal, and enhances the edge of the video signal A video signal correction device that:
A feature quantity extraction unit for extracting a feature quantity of the video signal;
An amplification factor deriving unit for deriving an amplification factor corresponding to the feature amount;
Further comprising
The video signal correction apparatus according to claim 1, wherein the amplifier amplifies an edge component with an amplification factor from the amplification factor deriving unit.   The video signal correction apparatus according to claim 1, wherein the feature amount extraction unit detects the feature amount based on a video signal in a predetermined region of the same frame.   The video signal correction apparatus according to claim 2, wherein the feature amount represents a degree of change in luminance between pixels constituting the predetermined area of the same frame.   4. The video signal correction apparatus according to claim 3, wherein the feature amount is an absolute luminance deviation of pixels constituting the predetermined area of the same frame.   The video signal correction apparatus according to claim 1, wherein the amplification factor deriving unit classifies the pixels into any of a predetermined number of sections based on the feature amount.   6. The video signal correction apparatus according to claim 5, wherein the amplification factor deriving unit derives the amplification factor of the pixel based on a classification to which the pixel belongs.   The predetermined number of sections includes a section in which the undulation of luminance of the peripheral pixels is flat, a section in which the peripheral pixels include the edge component to be emphasized, a section in which the peripheral pixels include a lot of noise components, and 7. The video signal correction apparatus according to claim 6, wherein the video signal correction apparatus is one or more sections selected from a group of sections in which a luminance difference between peripheral pixels is significant.   The video signal correction apparatus according to claim 7, wherein the amplification factor of the section in which the undulation of the brightness of the peripheral pixels is flat is 1. 9.   The amplification factor of the section in which the edge component to be emphasized is present in the peripheral pixels is higher than the amplification ratio of the section in which the undulation of the luminance of the peripheral pixels is flat. Video signal correction device.   The amplification factor of the segment in which the surrounding pixel includes a lot of noise components is higher than the amplification factor of the segment in which the luminance unevenness of the peripheral pixel is flat, and the peripheral pixel has the edge component to be emphasized The video signal correction device according to claim 7, wherein the video signal correction device is lower than an amplification factor of the section.   The amplification factor of the section in which the luminance difference between the peripheral pixels is severe is higher than the amplification factor of the section in which the undulation of the luminance of the peripheral pixels is flat, and the peripheral pixel has the edge component to be emphasized. 8. The video signal correcting apparatus according to claim 7, wherein the video signal correcting apparatus is lower than the amplification factor of the section.   6. The video signal correction according to claim 5, wherein the amplification factor deriving unit classifies the pixels into the predetermined number of categories based on the normalized feature value after normalizing the feature value. apparatus. A video signal correction method for correcting a video signal by a video signal correction device that emphasizes edges of the video signal:
The video signal correction device comprises:
Extracting an edge component of the video signal;
Extracting a feature amount of the video signal;
Deriving an amplification factor corresponding to the feature amount;
Amplifying the extracted edge component with the amplification factor;
Adding the amplified edge component to the original video signal;
A video signal correction method comprising: A video signal correction program for emphasizing edges of a video signal:
Computer
Extracting an edge component of the video signal;
Extracting a feature amount of the video signal;
Deriving an amplification factor corresponding to the feature amount;
Amplifying the extracted edge component with the amplification factor;
Adding the amplified edge component to the original video signal;
A video signal correction method program, characterized in that

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