JP2013228536A5

JP2013228536A5 -

Info

Publication number: JP2013228536A5
Application number: JP2012100043A
Authority: JP
Filing date: 2012-04-25
Publication date: 2015-06-11
Anticipated expiration: 2032-04-25

Description

本発明の一つの態様の画像処理装置は、
入力画像の特定の周波数帯域近傍の成分を取り出した第１の中間画像を生成する中間画像生成手段と、
前記第１の中間画像を入力とし第２の中間画像を生成する中間画像処理手段と、
前記第１の中間画像を入力とし前記第２の中間画像の各画素に対する補正強度を決定する補正強度決定手段と、
前記補正強度決定手段により各画素について決定された前記補正強度に応じた補正量だけ、前記第２の中間画像の当該画素の画素値の絶対値が小さくなるように、前記第２の中間画像に対する補正を行って、補正画像を出力する補正手段と、
前記入力画像と前記補正画像を加算する第１の加算手段と
を有し、
前記補正強度決定手段は、
前記第１の中間画像のそれぞれの画素の画素値の絶対値が所定の閾値より大きい場合１を出力し、それ以外の場合０を出力する比較手段と、
各画素を中心とする所定の範囲内に位置する画素についての前記比較手段の出力を加重加算する比較結果加算手段と
を有することを特徴とする。
本発明の他の態様の画像処理装置は、
入力画像の特定の周波数帯域近傍の成分を取り出した第１の中間画像を生成する中間画像生成手段と、
前記第１の中間画像を入力とし第２の中間画像を生成する中間画像処理手段と、
前記第１の中間画像を入力とし前記第２の中間画像の各画素に対する補正強度を決定する補正強度決定手段と、
前記補正強度決定手段により各画素について決定された前記補正強度に応じた補正量だけ、前記第２の中間画像の当該画素の画素値の絶対値が小さくなるように、前記第２の中間画像に対する補正を行って、補正画像を出力する補正手段と、
前記入力画像と前記補正画像を加算する第１の加算手段と
を有し、
前記補正強度決定手段は、
前記第１の中間画像のそれぞれの画素の画素値の絶対値が所定の閾値より小さい少なくとも一部の区間で０を出力し、それ以外の少なくとも一部の区間で前記第１の中間画像の画素値の絶対値の値の変化に対し連続的に変化する値を出力する比較手段と、
各画素を中心とする所定の範囲内に位置する画素についての前記比較手段の出力を加重加算する比較結果加算手段と
を有することを特徴とする。 An image processing apparatus according to one aspect of the present invention includes:
Intermediate image generating means for generating a first intermediate image obtained by extracting a component in the vicinity of a specific frequency band of the input image;
Intermediate image processing means for receiving the first intermediate image and generating a second intermediate image;
Correction intensity determining means for receiving the first intermediate image as input and determining a correction intensity for each pixel of the second intermediate image;
With respect to the second intermediate image, the absolute value of the pixel value of the pixel of the second intermediate image is reduced by the correction amount corresponding to the correction intensity determined for each pixel by the correction intensity determining means. correction me a line, and a correction means for outputting a correction image,
Possess a first addition means for adding the corrected image and the input image,
The correction strength determining means includes
Comparing means for outputting 1 if the absolute value of the pixel value of each pixel of the first intermediate image is greater than a predetermined threshold, and outputting 0 otherwise.
Comparison result addition means for weighted addition of the output of the comparison means for pixels located within a predetermined range centered on each pixel;
Characterized in that it have a.
An image processing apparatus according to another aspect of the present invention includes:
Intermediate image generating means for generating a first intermediate image obtained by extracting a component in the vicinity of a specific frequency band of the input image;
Intermediate image processing means for receiving the first intermediate image and generating a second intermediate image;
Correction intensity determining means for receiving the first intermediate image as input and determining a correction intensity for each pixel of the second intermediate image;
With respect to the second intermediate image, the absolute value of the pixel value of the pixel of the second intermediate image is reduced by the correction amount corresponding to the correction intensity determined for each pixel by the correction intensity determining means. Correction means for performing correction and outputting a corrected image;
First addition means for adding the input image and the corrected image;
Have
The correction strength determining means includes
The absolute value of the pixel value of each pixel of the first intermediate image is output as 0 in at least some sections smaller than a predetermined threshold, and the pixels of the first intermediate image are output in at least some other sections. A comparison means for outputting a continuously changing value with respect to a change in absolute value of the value;
Comparison result addition means for weighted addition of the output of the comparison means for pixels located within a predetermined range centered on each pixel;
It is characterized by having.

図４は水平方向非線形処理手段２Ａｈの構成例を示す。図示の水平方向非線形処理手段２Ａｈは、ゼロクロス判定手段３１１ｈと、信号増幅手段３１２ｈとを備える。なお、水平方向非線形処理手段２Ａｈには、画像Ｄ１ｈが入力画像ＤＩＮ３１１ｈとして入力される。 FIG. 4 shows an example of the configuration of the horizontal nonlinear processing means 2Ah. The illustrated horizontal non-linear processing means 2Ah includes a zero-cross determining means 311h and a signal amplifying means 312h. Note that the image D1h is input to the horizontal nonlinear processing means 2Ah as the input image DIN311h.

図５は垂直方向非線形処理手段２Ａｖの構成例を示す。図示の垂直方向非線形処理手段２Ａｖは、ゼロクロス判定手段３１１ｖと、信号増幅手段３１２ｖとを備える。なお、垂直方向非線形処理手段２Ａｖには、画像Ｄ１ｖが入力画像ＤＩＮ３１１ｖとして入力される。 FIG. 5 shows a configuration example of the vertical nonlinear processing means 2Av. The illustrated vertical non-linear processing means 2Av includes a zero-cross determining means 311v and a signal amplifying means 312v. Note that the image D1v is input to the vertical nonlinear processing means 2Av as the input image DIN311v.

比較結果加算手段３Ｂは比較結果Ｄ３Ａとして得られる出力値を複数画素分加算し、その結果を加算結果Ｄ３Ｂとして出力する。この加算においては、各画素（注目画素）について、当該注目画素を中心とする所定の範囲内に位置する複数の画素についての比較結果Ｄ３Ａとして得られる出力値が加算される。この加算処理は比較結果Ｄ３Ａｈ、Ｄ３Ａｖのそれぞれに対して行う。すなわち比較結果加算手段３Ｂは、比較結果Ｄ３Ａｈに対して後述の処理を行う水平方向比較結果加算手段３Ｂｈと、比較結果Ｄ３Ａｖに対して後述の処理を行う垂直方向比較結果加算手段３Ｂｖとを備え、加算結果Ｄ３Ｂは、水平方向比較結果加算手段３Ｂｈが出力する加算結果Ｄ３Ｂｈと、垂直方向比較結果加算手段３Ｂｖが出力する加算結果Ｄ３Ｂｖから成る。以下、水平方向比較結果加算手段３Ｂｈ、及び垂直方向比較結果加算手段３Ｂｖの動作についてさらに説明する。 The comparison result adding means 3B adds the output values obtained as the comparison result D3A for a plurality of pixels, and outputs the result as the addition result D3B. In this addition, for each pixel (target pixel), an output value obtained as a comparison result D3A for a plurality of pixels located within a predetermined range centered on the target pixel is added. This addition processing is performed for each of the comparison results D3Ah and D3Av. That is, the comparison result addition unit 3B includes a horizontal direction comparison result addition unit 3Bh that performs processing described later on the comparison result D3Ah, and a vertical direction comparison result addition unit 3Bv that performs processing described later on the comparison result D3Av. The addition result D3B includes an addition result D3Bh output from the horizontal direction comparison result addition unit 3Bh and an addition result D3Bv output from the vertical direction comparison result addition unit 3Bv. Hereinafter, the operations of the horizontal direction comparison result adding unit 3Bh and the vertical direction comparison result adding unit 3Bv will be further described.

補正手段４について説明する。図９は補正手段４の構成例を示す。図示の補正手段４は、補正量決定手段４Ａと、補正演算手段４Ｂとを備える。 The correction unit 4 will be described. FIG. 9 shows a configuration example of the correction means 4. The illustrated correction unit 4 includes a correction amount determination unit 4A and a correction calculation unit 4B.

図１３は画像拡大手段Ｕ１の構成例を示す。図示の画像拡大手段Ｕ１は水平方向ゼロ挿入手段Ｕ１Ａ、水平方向低周波数成分通過手段Ｕ１Ｂ、垂直方向ゼロ挿入手段Ｕ１Ｃ、及び垂直方向低周波数成分通過手段Ｕ１Ｄを備える。水平方向ゼロ挿入手段Ｕ１Ａは原画ＤＯＲＧの水平方向に関して画素値０を持つ画素を適宜挿入した画像ＤＵ１Ａを生成する。水平方向低周波数成分通過手段Ｕ１Ｂはローパスフィルタ処理により画像ＤＵ１Ａの低周波数成分のみを取り出した画像ＤＵ１Ｂを生成する。垂直方向ゼロ挿入手段Ｕ１Ｃは画像ＤＵ１Ｂの垂直方向に関して画素値０を持つ画素を適宜挿入した画像ＤＵ１Ｃを生成する。垂直方向低周波数成分通過手段Ｕ１Ｄはローパスフィルタ処理により画像ＤＵ１Ｃの低周波数成分のみを取り出した画像ＤＵ１Ｄを生成する。そして画像ＤＵ１Ｄが原画ＤＯＲＧを水平方向及び垂直方向とも２倍した画像ＤＵ１として、画像拡大手段Ｕ１から出力される。 FIG. 13 shows a configuration example of the image enlarging means U1. The illustrated image enlargement means U1 includes a horizontal direction zero insertion means U1A, a horizontal direction low frequency component passage means U1B, a vertical direction zero insertion means U1C, and a vertical direction low frequency component passage means U1D. The horizontal zero insertion means U1A generates an image DU1A in which pixels having a pixel value of 0 in the horizontal direction of the original image DORG are appropriately inserted. The horizontal direction low frequency component passing means U1B generates an image DU1B in which only the low frequency component of the image DU1A is extracted by low pass filter processing. The vertical zero insertion unit U1C generates an image DU1C in which pixels having a pixel value of 0 in the vertical direction of the image DU1B are appropriately inserted. The vertical low-frequency component passing hands stage U 1D generates image DU1D obtained by extracting only low frequency components of the image DU1C low-pass filtering. The image DU1D is output from the image enlargement unit U1 as an image DU1 obtained by doubling the original image DORG in both the horizontal and vertical directions.

図１５（Ａ）〜（Ｄ）は、画像拡大手段Ｕ１による処理の作用を周波数空間上で表したものであり、図１５（Ａ）は原画ＤＯＲＧの周波数スペクトル、図１５（Ｂ）は画像ＤＵ１Ａの周波数スペクトル、図１５（Ｃ）は水平方向低周波数成分通過手段Ｕ１Ｂの周波数応答、図１５（Ｄ）は画像ＤＵ１Ｂの周波数スペクトルを表している。なお、図１５（Ａ）〜（Ｄ）において横軸は水平方向の空間周波数を表す周波数軸であり、縦軸は周波数スペクトルもしくは周波数応答の強度を表している。なお原画ＤＯＲＧの画素数は入力画像ＤＩＮの半分となっており、言い換えると原画ＤＯＲＧのサンプリング間隔は入力画像ＤＩＮのサンプリング間隔の２倍になっている。したがって原画ＤＯＲＧのナイキスト周波数は入力画像ＤＩＮのナイキスト周波数の半分すなわち、Ｆｎ／２となる。 FIGS. 15A to 15D show the processing effect of the image enlarging means U1 on the frequency space, FIG. 15A shows the frequency spectrum of the original image DORG, and FIG. 15B shows the image DU1A. FIG. 15C shows the frequency response of the horizontal low frequency component passing means U1B, and FIG. 15D shows the frequency spectrum of the image DU1B. 15A to 15D, the horizontal axis is the frequency axis representing the spatial frequency in the horizontal direction, and the vertical axis represents the frequency spectrum or the intensity of the frequency response. Note that the number of pixels of the original image DORG is half that of the input image DIN. In other words, the sampling interval of the original image DORG is twice the sampling interval of the input image DIN. Therefore, the Nyquist frequency of the original image DORG is half of the Nyquist frequency of the input image DIN, that is, Fn / 2.

以下、本発明に係る画像処理装置の作用、効果について説明する。
図１６（Ａ）〜（Ｅ）は入力画像ＤＩＮ（もしくは画像ＤＵ１）として原画ＤＯＲＧを拡大して得られた画像ＤＵ１Ｄが入力された場合の、入力画像ＤＩＮから中間画像Ｄ１を生成する際の作用、効果を模式的に表した図であり、図１６（Ａ）は入力画像ＤＩＮの周波数スペクトルを、図１６（Ｂ）は高周波数成分画像生成手段１Ａの周波数応答を、図１６（Ｃ）は低周波数成分画像生成手段１Ｂの周波数応答を、図１６（Ｄ）は中間画像生成手段１の周波数応答を、図１６（Ｅ）は中間画像Ｄ１の周波数スペクトルを表す。なお、図１６（Ａ）〜（Ｅ）においても図１５（Ａ）〜（Ｄ）と同様の理由で周波数軸は１本しか用いていない。 The operation and effect of the image processing apparatus according to the present invention will be described below.
FIGS. 16A to 16E show the operation when the intermediate image D1 is generated from the input image DIN when the image DU1D obtained by enlarging the original image DORG is input as the input image DIN (or image DU1). FIG. 16A schematically shows the effect, FIG. 16A shows the frequency spectrum of the input image DIN, FIG. 16B shows the frequency response of the high-frequency component image generating means 1 A , and FIG. Represents the frequency response of the low frequency component image generation means 1B , FIG. 16D represents the frequency response of the intermediate image generation means 1, and FIG. 16E represents the frequency spectrum of the intermediate image D1. In FIGS. 16A to 16E, only one frequency axis is used for the same reason as in FIGS. 15A to 15D.

図１７（Ａ）〜（Ｃ）は中間画像処理手段２の作用、効果を表した図であり、図１７（Ａ）は非線形処理画像Ｄ２Ａの周波数スペクトルを、図１７（Ｂ）は高周波数成分画像生成手段２Ｂの周波数応答を、図１７（Ｃ）は画像Ｄ２Ｂの周波数スペクトルを表す。なお、図１７（Ａ）〜（Ｃ）では、図１６（Ａ）〜（Ｅ）と同様の理由で、空間周波数が０以上となる範囲でのみ周波数スペクトル或いは周波数応答の強度を表している。 17 (A) to 17 (C) are views showing the operation and effect of the intermediate image processing means 2, FIG. 17 (A) shows the frequency spectrum of the nonlinear processed image D2A, and FIG. 17 (B) shows the high frequency component. FIG. 17C shows the frequency response of the image generation means 2B, and FIG. 17C shows the frequency spectrum of the image D2B. In FIGS. 17A to 17C, for the same reason as FIGS. 16A to 16E, the intensity of the frequency spectrum or the frequency response is shown only in the range where the spatial frequency is 0 or more.

また、本発明による画像処理装置では、補正強度Ｄ３に所定の係数を乗ずるといった方法で補正量Ｄ４Ａを求めたが、この際、補正強度Ｄ３に乗ずる係数を中間画像Ｄ２の画素値の符号が正の場合と負の場合で異なるものとすれば、輝度が明るくなる場合と暗くなる場合とで異なる程度に補正を加えることが可能になる。 Further, in the image processing apparatus according to the present invention has determined the correction amount D4 A to the correction intensity D3 in such a way multiplied by a predetermined coefficient, this time, the sign of the coefficient to be multiplied to the correction intensity D3 pixel values of intermediate image D2 If it is different between the positive case and the negative case, it is possible to make corrections to different extents depending on whether the luminance becomes brighter or darker.

また、水平方向比較手段３Ａｈで用いる閾値を画像Ｄ１ｈの画素値の符号が正の場合と負の場合で異なる値としたり、垂直方向比較手段３Ａｖで用いる閾値を画像Ｄ１ｖの画素値の符号が正の場合と負の場合で異なる値としたり、比較手段３Ａで用いる閾値を中間画像Ｄ１の画素値の符号が正の場合と負の場合で異なる値とすることでも、輝度が明るくなる場合と暗くなる場合とで、異なる程度に補正を加えることが可能になる。 In addition, the threshold value used in the horizontal direction comparison unit 3Ah is set to a different value depending on whether the sign of the pixel value of the image D1h is positive or negative, or the threshold value used in the vertical direction comparison unit 3Av is set to have a positive sign of the pixel value of the image D1v. The threshold value used in the comparison means 3A is different from that in the case of negative and the case where the sign of the pixel value of the intermediate image D1 is positive and negative. It is possible to add corrections to different degrees.

図２４の変形例では、図６に示した補正強度決定手段３のように、比較手段３Ａ内部に、水平方向比較手段３Ａｈと垂直方向比較手段３Ａｖの双方を設ける必要がなければ、比較結果加算手段３Ｂ内部に、水平方向比較結果加算手段３Ｂｈと垂直方向比較結果加算手段３Ｂｖの双方を設ける必要もない。また、図１０に示した補正量決定手段４Ａのように、水平方向補正量決定手段４Ａｈと垂直方向補正量決定手段４Ａｖの双方を設ける必要もない。したがって、この変形例では、その回路規模を小さくすることが出来る。 In the modification of FIG. 24, as in the correction intensity determination means 3 shown in FIG. 6, the comparison means 3 A Internal, if there is no need to provide both a horizontal direction comparing means 3Ah and a vertical direction comparing means 3Av, comparison It is not necessary to provide both the horizontal direction comparison result addition unit 3Bh and the vertical direction comparison result addition unit 3Bv in the result addition unit 3B. Further, unlike the correction amount determination means 4A shown in FIG. 10, it is not necessary to provide both the horizontal direction correction amount determination means 4Ah and the vertical direction correction amount determination means 4Av. Therefore, in this modification, the circuit scale can be reduced.

このような処理を行う場合、比較結果Ｄ３Ａを比較結果加算手段３Ｂで加算することで得られる、中間画像Ｄ１の各画素についての加算結果Ｄ３Ｂは、各画素とその周辺の領域を含む領域（近傍領域）内に絶対値の大きい画素がより多く存在するほどより大きな値となり、近傍領域内の画素の画素値の絶対値を重み付け加算する場合には、当該重み加算値が大きいほど大きな値となる。 When such a process is performed, the addition result D3B for each pixel of the intermediate image D1 obtained by adding the comparison result D3A by the comparison result addition unit 3B is an area (neighboring area) including each pixel and its surrounding area. The larger the number of pixels having a large absolute value in the region), the larger the value. In the case where the absolute values of the pixel values of the pixels in the neighboring region are weighted and added, the larger the weighted addition value, the larger the value. .

分割手段４０Ａは中間画像Ｄ２の各画素に関して、画素値の符号を表す信号と画素値の絶対値を複数の値に分割した結果を出力する。図示の例では、中間画像Ｄ２の画素値の符号を表す符号データＤ４０Ａ０と、画素値の絶対値を分割して得た３つの値Ｄ（１）、Ｄ（２）、Ｄ（３）から成る分割データＤ４０Ａ１を出力する。 Dividing means 40 A with respect to each pixel of the intermediate image D2, and outputs the result obtained by dividing the absolute value of the signal and the pixel value representing the sign of the pixel value to multiple values. In the example shown in the figure, it consists of code data D40A0 representing the code of the pixel value of the intermediate image D2, and three values D (1), D (2), and D (3) obtained by dividing the absolute value of the pixel value. The divided data D40A1 is output.

図３０は中間画像処理手段２０の構成例を示す。図３０において、図３と同じ符号で表される構成要素は実施の形態１と同様の動作を行うのでその説明は省略する。図３０の中間画像処理手段２０は、図３の中間画像処理手段２と概して同じであるが、以下の点で異なる。即ち、補正手段２Ｃ１、２Ｃ２が付加され、図３の加算手段２Ｃの代わりに、加算手段２Ｄが設けられている。以下、補正手段２Ｃ１、２Ｃ２、及び加算手段２Ｄについて説明する。 FIG. 30 shows a configuration example of the intermediate image processing means 20. In FIG. 30, the constituent elements denoted by the same reference numerals as those in FIG. The intermediate image processing means 20 in FIG. 30 is generally the same as the intermediate image processing means 2 in FIG. 3, but differs in the following points. That is, correction means 2C1 and 2C2 are added, and an addition means 2D is provided instead of the addition means 2C of FIG. Hereinafter, the correcting means 2C1 and 2C2 and the adding means 2D will be described.

加算手段２Ｄは画像Ｄ２Ｃ１、Ｄ２Ｃ２を加算する。
ここで画像Ｄ２Ｃ１は画像Ｄ２Ｃ１ｈ、Ｄ２Ｃ１ｖから成り、画像Ｄ２Ｃ２は画像Ｄ２Ｃ２ｈ、Ｄ２Ｃ２ｖから成るので、画像Ｄ２Ｃ１、Ｄ２Ｃ２を加算するとは画像Ｄ２Ｃ１ｈ、Ｄ２Ｃ１ｖ、Ｄ２Ｃ２ｈ、Ｄ２Ｃ２ｖを加算することを意味する。なお、ここでの加算は単純加算であってもよいし重み付け加算であってもよい。 The adding means 2D adds the images D2C1 and D2C2.
Here, the image D 2C1 is composed of images D2C1h and D2C1v, and the image D 2C2 is composed of images D2C2h and D2C2v. Therefore, adding the images D2C1 and D2C2 means adding the images D2C1h, D2C1v, D2C2h, and D2C2v. The addition here may be simple addition or weighted addition.

ここで仮に補正手段２Ｃ１、２Ｃ２による補正が加えられなかった場合を考える。この場合、中間画像Ｄ２は画像Ｄ１ｈ、Ｄ１ｖ、Ｄ２Ｂｈ、Ｄ２Ｂｖを加算して得られることになる。したがって、画像Ｄ１ｈ、Ｄ１ｖ、Ｄ２Ｂｈ、Ｄ２Ｂｖの画素値が大きな正の値や小さな負の値をとっている箇所では中間画像Ｄ２の画素値も大きな正の値や小さな負の値をとりやすいと考えられる。 Here, let us consider a case where correction by the correction means 2C1 and 2C2 is not applied. In this case, the intermediate image D2 is obtained by adding the images D1h, D1v, D2Bh, and D2Bv. Therefore, it is considered that the pixel value of the intermediate image D2 is likely to take a large positive value or a small negative value when the pixel values of the images D1h, D1v, D2Bh, D2Bv are large positive values or small negative values. It is done.

加算手段２Ｇは、画像Ｄ２Ｆ１、Ｄ２Ｆ２を加算した結果を中間画像Ｄ２として出力する。ここで加算の方法は単純加算でも加重加算でもよい。 The adding means 2G outputs the result of adding the images D2F1 and D2F2 as an intermediate image D2. Here, the addition method may be simple addition or weighted addition.

ここで仮に補正手段２Ｆ１、２Ｆ２による補正が加えられなかった場合を考える。この場合、中間画像Ｄ２は画像Ｄ２Ｅ１、Ｄ２Ｅ２を加算して得られることになる。したがって画像Ｄ２Ｅ１や画像Ｄ２Ｅ２の画素値が大きな正の値や小さな負の値をとっている箇所では中間画像Ｄ２の画素値も大きな正の値や小さな負の値をとりやすいと考えられる。 Here, let us consider a case where correction by the correction means 2F1 and 2F2 is not applied. In this case, the intermediate image D2 is obtained by adding the images D2E1 and D2E2. Therefore, it is considered that the pixel value of the intermediate image D2 is likely to take a large positive value or a small negative value at a location where the pixel value of the image D2E1 or the image D2E2 takes a large positive value or a small negative value.

一方、先に述べたように、補正手段２Ｆ１では、画像Ｄ２Ｅ１に対し、その画素値が大きな正の値や小さな負の値をとっている箇所でその振幅が減衰するよう補正が加えられ、補正手段２Ｆ２では、画像Ｄ２Ｅ２に対し、その画素値が大きな正の値や小さな負の値をとっている箇所でその振幅が減衰するよう補正が加えられるので、それらを加算して得られる中間画像Ｄ２は、その画素値が大きな正の値や小さな負の値になる箇所では、その振幅が減衰するよう補正が加えられたものとなる。したがって、中間画像Ｄ２によって入力画像ＤＩＮに含まれる輝度変化が大きくなる程度を軽減することができ、周期的な模様が動いた部分に発生しうる点滅を抑えることが可能になる。 On the other hand, as described above, in the correction means 2F1, correction is applied to the image D2E1 so that the amplitude is attenuated at a location where the pixel value takes a large positive value or a small negative value. In the means 2F2, the image D2E2 is corrected so that the amplitude is attenuated at a place where the pixel value takes a large positive value or a small negative value, so that an intermediate image D obtained by adding them is added. No. 2 is corrected so that the amplitude is attenuated at a location where the pixel value becomes a large positive value or a small negative value. Therefore, it is possible to reduce the extent to which the luminance change included in the input image DIN becomes large due to the intermediate image D2, and it is possible to suppress blinking that may occur in a portion where the periodic pattern has moved.

高周波数成分画像生成ステップＳＴ１Ａでは、図示しない画像入力ステップにて入力された入力画像ＤＩＮに対し、以下のような処理が行われる。まず、水平方向高周波数成分画像生成ステップＳＴ１Ａｈでは、水平方向のハイパスフィルタ処理によって、入力画像ＤＩＮから水平方向の高周波数成分を取り出した画像Ｄ１Ａｈを生成する。垂直方向高周波数成分画像生成ステップＳＴ１Ａｖでは、垂直方向のハイパスフィルタ処理によって、入力画像ＤＩＮから垂直方向の高周波数成分を取り出した画像Ｄ１Ａｖを生成する。すなわち、高周波数成分画像生成ステップＳＴ１Ａは、入力画像ＤＩＮから、画像Ｄ１Ａｈ及び画像Ｄ１Ａｖから成る画像Ｄ１Ａを生成する。この動作は高周波数成分画像生成手段１Ａと同等である。 In the high frequency component image generation step ST1A, the following processing is performed on the input image DIN input in an image input step (not shown). First, in the horizontal high-frequency component image generation step ST1Ah, an image D1Ah obtained by extracting a horizontal high-frequency component from the input image DIN is generated by horizontal high-pass filter processing. In the vertical high-frequency component image generation step ST1Av, an image D1Av obtained by extracting the high-frequency component in the vertical direction from the input image DIN is generated by high-pass filtering in the vertical direction. That is, the high frequency component image generation step ST1A generates an image D1A composed of the image D1Ah and the image D1Av from the input image DIN. This operation is equivalent to the high frequency component image generating means 1A.

非線形処理ステップＳＴ２Ａは、水平方向非線形処理ステップＳＴ２Ａｈ、及び垂直方向非線形処理ステップＳＴ２Ａｖを含み、高周波数成分画像生成ステップＳＴ２Ｂは、水平方向高周波数成分画像生成ステップＳＴ２Ｂｈ、及び垂直方向高周波数成分画像生成ステップＳＴ２Ｂｖを含む。 The non-linear processing step ST2A includes a horizontal non-linear processing step ST2Ah and a vertical non-linear processing step ST2Av, and the high frequency component image generation step ST2B includes a horizontal high frequency component image generation step ST2Bh and a vertical high frequency component image generation. Step ST2Bv is included.

非線形処理ステップＳＴ２Ａでは第１の中間画像Ｄ１に対し、以下のような処理を行う。
まず、水平方向非線形処理ステップＳＴ２Ａｈでは、図３５に示すフローに従った処理で画像Ｄ１ｈから画像Ｄ２Ａｈを生成する。図３５に示すフローでの処理は以下の通りである。まず、ゼロクロス判定ステップＳＴ３１１ｈでは、画像Ｄ１ｈにおける画素値の変化を水平方向に沿って確認する。そして画素値が正の値から負の値或いは負の値から正の値へと変化する箇所をゼロクロス点として捉え、ゼロクロス点の左右に位置する画素を信号増幅ステップＳＴ３１２ｈに通知する。信号増幅ステップＳＴ３１２ｈでは画像Ｄ１ｈについて、ゼロクロス点の左右に位置すると通知された画素の画素値を増幅し、その画像を画像Ｄ２Ａｈとして出力する。すなわち、水平方向非線形処理ステップＳＴ２Ａｈは、画像Ｄ１ｈに対し、水平方向非線形処理手段２Ａｈと同様の処理を行い、画像Ｄ２Ａｈを生成する。 In the nonlinear processing step ST2A, the following processing is performed on the first intermediate image D1.
First, in the horizontal non-linear processing step ST2Ah, an image D2Ah is generated from the image D1h by processing according to the flow shown in FIG. The processing in the flow shown in FIG. 35 is as follows. First, in the zero cross determination step ST311h, a change in pixel value in the image D1h is confirmed along the horizontal direction. A location where the pixel value changes from a positive value to a negative value or from a negative value to a positive value is regarded as a zero cross point, and the pixels located on the left and right of the zero cross point are notified to the signal amplification step ST312h. In the signal amplification step ST312h, for the image D1h, the pixel value of the pixel notified to be positioned on the left and right of the zero cross point is amplified, and the image is output as the image D2Ah. That is, in the horizontal non-linear processing step ST2Ah, the image D1h is subjected to the same processing as the horizontal non-linear processing means 2Ah to generate the image D2Ah.

次に、垂直方向非線形処理ステップＳＴ２Ａｖでは、図３６に示すフローに従った処理で画像Ｄ１ｖから画像Ｄ２Ａｖを生成する。図３６に示すフローでの処理は以下の通りである。まず、ゼロクロス判定ステップＳＴ３１１ｖでは、画像Ｄ１ｖにおける画素値の変化を垂直方向に沿って確認する。そして画素値が正の値から負の値或いは負の値から正の値へと変化する箇所をゼロクロス点として捉え、ゼロクロス点の上下に位置する画素を信号増幅ステップＳＴ３１２ｖに通知する。信号増幅ステップＳＴ３１２ｖでは画像Ｄ１ｖについて、ゼロクロス点の上下に位置すると通知された画素の画素値を増幅し、その画像を画像Ｄ２Ａｖとして出力する。すなわち、垂直方向非線形処理ステップＳＴ２Ａｖは、画像Ｄ１ｖに対し、垂直方向非線形処理手段２Ａｖと同様の処理を行い、画像Ｄ２Ａｖを生成する。 Next, in the vertical nonlinear processing step ST2Av, an image D2Av is generated from the image D1v by processing according to the flow shown in FIG. The processing in the flow shown in FIG. 36 is as follows. First, in the zero cross determination step ST311v, a change in pixel value in the image D1v is confirmed along the vertical direction. Then, a point where the pixel value changes from a positive value to a negative value or from a negative value to a positive value is regarded as a zero cross point, and the pixels located above and below the zero cross point are notified to the signal amplification step ST312v. In the signal amplification step ST312v, the pixel value of the pixel notified to be positioned above and below the zero cross point is amplified for the image D1v, and the image is output as the image D2Av. That is, in the vertical non-linear processing step ST2Av, the image D1v is subjected to the same processing as the vertical non-linear processing means 2Av to generate the image D2Av.

垂直方向比較結果加算ステップＳＴ３Ｂｖは垂直方向比較結果加算手段３Ｂｖと同様の方法で加算結果Ｄ３Ｂｖを計算する。すなわち、各画素についての比較結果Ｄ３Ａｖについて、その画素を中心とした所定の範囲内に存在する画素の画素値を加算し、その結果を加算結果Ｄ３Ｂｖとする。 In the vertical direction comparison result addition step ST3Bv, the addition result D3Bv is calculated in the same manner as the vertical direction comparison result addition means 3Bv. That is, for the comparison result D3Av for each pixel, the pixel values of the pixels existing within a predetermined range centered on that pixel are added, and the result is taken as the addition result D3 B v.

補正量決定ステップＳＴ４Ａは補正量Ｄ４Ａを決定する。補正量Ｄ４Ａの決定は補正量決定手段４Ａと同様に行われる。補正量決定ステップＳＴ４Ａは、例えば図３９に示すように、水平方向補正量決定ステップＳＴ４Ａｈ、垂直方向補正量決定ステップＳＴ４Ａｖ、加算ステップＳＴ４Ａｐを含む。以下、補正量決定ステップＳＴ４Ａの動作の詳細を述べる。 The correction amount determination step ST4A determines the correction amount D4A. The determination of the correction amount D4 A is performed similarly to the correction amount determining unit 4 A. For example, as shown in FIG. 39, the correction amount determination step ST4A includes a horizontal direction correction amount determination step ST4Ah, a vertical direction correction amount determination step ST4Av, and an addition step ST4Ap. Details of the operation of the correction amount determination step ST4A will be described below.

加算ステップＳＴ２Ｄは画像Ｄ２Ｃ１、Ｄ２Ｃ２を加算する。
ここで画像Ｄ２Ｃ１は画像Ｄ２Ｃ１ｈ、Ｄ２Ｃ１ｖから成り、画像Ｄ２Ｃ２は画像Ｄ２Ｃ２ｈ、Ｄ２Ｃ２ｖから成るので、画像Ｄ２Ｃ１、Ｄ２Ｃ２を加算するとは画像Ｄ２Ｃ１ｈ、Ｄ２Ｃ１ｖ、Ｄ２Ｃ２ｈ、Ｄ２Ｃ２ｖを加算することを意味する。なお、ここでの加算は単純加算であってもよいし重み付け加算であってもよい。 In addition step ST2D, the images D2C1 and D2C2 are added.
Here, the image D 2C1 is composed of images D2C1h and D2C1v, and the image D 2C2 is composed of images D2C2h and D2C2v. Therefore, adding the images D2C1 and D2C2 means adding the images D2C1h, D2C1v, D2C2h, and D2C2v. The addition here may be simple addition or weighted addition.

加算ステップＳＴ２Ｇは、画像Ｄ２Ｆ１、Ｄ２Ｆ２を加算した結果を中間画像Ｄ２として出力する。ここで加算の方法は単純加算でも加重加算でもよい。
以上が中間画像処理ステップＳＴ２０の構成及び動作である。 The addition step ST2G outputs the result of adding the images D2F1 and D2F2 as an intermediate image D2. Here, the addition method may be simple addition or weighted addition.
The above is the configuration and operation of the intermediate image processing step ST20.

Claims

Intermediate image generating means for generating a first intermediate image obtained by extracting a component in the vicinity of a specific frequency band of the input image;
Intermediate image processing means for receiving the first intermediate image and generating a second intermediate image;
Correction intensity determining means for receiving the first intermediate image as input and determining a correction intensity for each pixel of the second intermediate image;
With respect to the second intermediate image, the absolute value of the pixel value of the pixel of the second intermediate image is reduced by the correction amount corresponding to the correction intensity determined for each pixel by the correction intensity determining means. correction me a line, and a correction means for outputting a correction image,
Possess a first addition means for adding the corrected image and the input image,
The correction strength determining means includes
Comparing means for outputting 1 if the absolute value of the pixel value of each pixel of the first intermediate image is greater than a predetermined threshold, and outputting 0 otherwise.
Comparison result addition means for weighted addition of the output of the comparison means for pixels located within a predetermined range centered on each pixel;
The image processing apparatus characterized by have a.

Intermediate image generating means for generating a first intermediate image obtained by extracting a component in the vicinity of a specific frequency band of the input image;
Intermediate image processing means for receiving the first intermediate image and generating a second intermediate image;
Correction intensity determining means for receiving the first intermediate image as input and determining a correction intensity for each pixel of the second intermediate image;
With respect to the second intermediate image, the absolute value of the pixel value of the pixel of the second intermediate image is reduced by the correction amount corresponding to the correction intensity determined for each pixel by the correction intensity determining means. Correction means for performing correction and outputting a corrected image;
First addition means for adding the input image and the corrected image;
Have
The correction strength determining means includes
The absolute value of the pixel value of each pixel of the first intermediate image is output as 0 in at least some sections smaller than a predetermined threshold, and the pixels of the first intermediate image are output in at least some other sections. A comparison means for outputting a continuously changing value with respect to a change in the absolute value of the value;
Each pixel images processor you; and a comparison result adder means for weighted addition of the output of said comparing means for the pixels located within a predetermined range centered on.

Wherein the predetermined threshold value, the image processing apparatus according to claim 1 or 2, characterized in that the sign of the pixel value of the first intermediate image is a different value in the case when the negative positive.

The correction means includes
It is zero when the correction intensity is less than the first predetermined magnitude, and is at least a second predetermined magnitude in at least a part of the section where the correction intensity is equal to or greater than the first predetermined magnitude. Correction amount calculation means for obtaining the correction amount so that
The correction amount only, so that the absolute value becomes smaller pixel value of the second intermediate image, according to claim 1 or 2; and a correction calculating means for correcting operation on the second intermediate image the image processing apparatus according to.

Intermediate image generating means for generating a first intermediate image obtained by extracting a component in the vicinity of a specific frequency band of the input image;
Intermediate image processing means for receiving the first intermediate image and generating a second intermediate image;
Correction means for receiving the second intermediate image as input and outputting a corrected image obtained by correcting the second intermediate image;
First adding means for adding the input image and the corrected image;
The correction means includes
The pixel value of the second intermediate image is converted into code data representing a code of the pixel value and first divided data obtained by dividing the absolute value of the pixel value into n values (n is an integer of 2 or more). A dividing means for dividing;
Divided data processing means for generating second divided data consisting of n values in which at least one value is attenuated among the n values constituting the first divided data;
And combining means for outputting a value obtained by adding a code represented by the code data to a value obtained by adding n values constituting the second divided data. Processing equipment.

When the absolute value of the pixel value is D and n−1 thresholds satisfying TH (j) ≦ TH (j + 1) are represented by TH (j) (j = 1 to n−1),
Of the n values D (j) (j = 1 to n) constituting the first divided data,
The first value D (1) is represented by the following equation:

The nth value D (n) is represented by the following equation:

The j-th value D (j) (2 ≦ j ≦ n−1) is expressed by the following equation:

further,
The divided data processing means includes n-1 values from the second value D (2) to the nth value D (n) among the n values D (j) represented by the above formula. The image processing apparatus according to claim 5 , wherein at least one of the values is attenuated.

Intermediate image generating means for generating a first intermediate image obtained by extracting a component in the vicinity of a specific frequency band of the input image;
Intermediate image processing means for receiving the first intermediate image and generating a second intermediate image;
First addition means for adding the input image and the second intermediate image;
The intermediate image processing means includes
Correction means for correcting the first intermediate image;
The correction means includes
The pixel value of the first intermediate image is converted into code data representing a sign of the pixel value and first divided data obtained by dividing the absolute value of the pixel value into n values (n is an integer of 2 or more). A dividing means for dividing;
Divided data processing means for generating second divided data consisting of n values in which at least one value is attenuated among the n values constituting the first divided data;
And a combining unit that outputs a value obtained by adding a code represented by the code data to a value obtained by adding n values constituting the second divided data. Processing equipment.

Intermediate image generating means for generating a first intermediate image obtained by extracting a component in the vicinity of a specific frequency band of the input image;
Intermediate image processing means for receiving the first intermediate image and generating a second intermediate image;
First addition means for adding the input image and the second intermediate image;
The intermediate image processing means includes
Non-linear processing means for changing the content of processing in accordance with the pixels of the first intermediate image;
A high-frequency component image generating means for generating a high-frequency component image obtained by extracting only the high-frequency component of the image output by the nonlinear processing means;
Correction means for correcting the high-frequency component image,
The correction means includes
The pixel value of the high-frequency component image is divided into code data representing a sign of the pixel value and first divided data obtained by dividing the absolute value of the pixel value into n values (n is an integer of 2 or more). Dividing means to
Divided data processing means for generating second divided data consisting of n values in which at least one value is attenuated among the n values constituting the first divided data;
And a combining unit that outputs a value obtained by adding a code represented by the code data to a value obtained by adding n values constituting the second divided data. Processing equipment.

An intermediate for generating a first intermediate image composed of a horizontal intermediate image obtained by extracting components near a specific frequency band in the horizontal direction of the input image and a vertical intermediate image obtained by extracting components near a specific frequency band in the vertical direction Image generating means;
Intermediate image processing means for receiving the first intermediate image and generating a second intermediate image;
First addition means for adding the input image and the second intermediate image;
The intermediate image processing means includes
Second addition means for adding the horizontal intermediate image and the vertical intermediate image;
Correction means for correcting the image output by the second addition means;
The correction means includes
A first pixel value obtained by dividing the pixel value of the image output by the second adding means into code data representing the sign of the pixel value and n absolute values of the pixel value (n is an integer of 2 or more). Dividing means for dividing into divided data;
Divided data processing means for generating second divided data consisting of n values in which at least one value is attenuated among the n values constituting the first divided data;
And a combining unit that outputs a value obtained by adding a code represented by the code data to a value obtained by adding n values constituting the second divided data. Processing equipment.

An intermediate for generating a first intermediate image composed of a horizontal intermediate image obtained by extracting components near a specific frequency band in the horizontal direction of the input image and a vertical intermediate image obtained by extracting components near a specific frequency band in the vertical direction Image generating means;
Intermediate image processing means for receiving the first intermediate image and generating a second intermediate image;
First addition means for adding the input image and the second intermediate image;
The intermediate image processing means includes
Horizontal non-linear processing means for changing the content of processing according to the pixels of the horizontal intermediate image;
A horizontal high-frequency component image generating means for generating a horizontal high-frequency component image obtained by extracting only the high-frequency component of the image output by the horizontal nonlinear processing means;
Vertical non-linear processing means for changing the content of the processing according to the pixels of the vertical intermediate image;
Vertical high frequency component image generation means for generating a vertical high frequency component image obtained by extracting only the high frequency component of the image output by the vertical nonlinear processing means;
Second addition means for adding the horizontal high-frequency component image and the vertical high-frequency component image;
Correction means for correcting an image output from the second addition means;
The correction means includes
A first pixel value obtained by dividing the pixel value of the image output from the second adding means into code data representing the sign of the pixel value and n absolute values of the pixel value (n is an integer of 2 or more). Dividing means for dividing into divided data;
Divided data processing means for generating second divided data consisting of n values in which at least one value is attenuated among the n values constituting the first divided data;
And a synthesis unit that outputs a value obtained by adding a code represented by the code data to a value obtained by adding n values constituting the second divided data. Processing equipment.

The image display apparatus having an image processing apparatus according to any one of claims 1 10.

An intermediate image generation step of generating a first intermediate image obtained by extracting a component in the vicinity of a specific frequency band of the input image;
An intermediate image processing step that receives the first intermediate image as an input and generates a second intermediate image;
A correction intensity determination step for determining a correction intensity for each pixel of the second intermediate image using the first intermediate image as an input;
With respect to the second intermediate image, the absolute value of the pixel value of the pixel of the second intermediate image is reduced by the correction amount corresponding to the correction intensity determined for each pixel in the correction intensity determination step. correction me a line, and a correction step of outputting the corrected image,
Possess a first adding step of adding the corrected image and the input image,
The correction intensity determination step includes
A comparison step of outputting 1 if the absolute value of the pixel value of each pixel of the first intermediate image is greater than a predetermined threshold, and outputting 0 otherwise.
A comparison result addition step for weighted addition of the output of the comparison step for pixels located within a predetermined range centered on each pixel;
An image processing method characterized by have a.

  An intermediate image generation step of generating a first intermediate image obtained by extracting a component in the vicinity of a specific frequency band of the input image;
  An intermediate image processing step that receives the first intermediate image as an input and generates a second intermediate image;
  A correction intensity determination step for determining a correction intensity for each pixel of the second intermediate image using the first intermediate image as an input;
  With respect to the second intermediate image, the absolute value of the pixel value of the pixel of the second intermediate image is reduced by the correction amount corresponding to the correction intensity determined for each pixel in the correction intensity determination step. A correction step of performing correction and outputting a corrected image;
  A first addition step of adding the input image and the corrected image;
  Have
  The correction intensity determination step includes
  The absolute value of the pixel value of each pixel of the first intermediate image is output as 0 in at least some sections smaller than a predetermined threshold, and the pixels of the first intermediate image are output in at least some other sections. A comparison step for outputting a continuously changing value with respect to a change in the absolute value of the value;
  A comparison result addition step for weighted addition of the output of the comparison step for pixels located within a predetermined range centered on each pixel.
  An image processing method.

An intermediate image generation step of generating a first intermediate image obtained by extracting a component in the vicinity of a specific frequency band of the input image;
An intermediate image processing step that receives the first intermediate image as an input and generates a second intermediate image;
A correction step of receiving the second intermediate image as an input and outputting a corrected image obtained by correcting the second intermediate image;
A first addition step of adding the input image and the corrected image;
The correction step includes
The pixel value of the second intermediate image is converted into code data representing a code of the pixel value and first divided data obtained by dividing the absolute value of the pixel value into n values (n is an integer of 2 or more). A splitting step to split;
A divided data processing step of generating second divided data composed of n values in which at least one value is attenuated among n values constituting the first divided data;
And a synthesis step of outputting a value obtained by adding a code represented by the code data to a value obtained by adding n values constituting the second divided data. Processing method.

An intermediate image generation step of generating a first intermediate image obtained by extracting a component in the vicinity of a specific frequency band of the input image;
An intermediate image processing step that receives the first intermediate image as an input and generates a second intermediate image;
A first addition step of adding the input image and the second intermediate image;
The intermediate image processing step includes
A correction step of correcting the first intermediate image,
The correction step includes
The pixel value of the first intermediate image is converted into code data representing a sign of the pixel value and first divided data obtained by dividing the absolute value of the pixel value into n values (n is an integer of 2 or more). A splitting step to split;
A divided data processing step of generating second divided data composed of n values in which at least one value is attenuated among n values constituting the first divided data;
And a synthesis step of outputting a value obtained by adding a code represented by the code data to a value obtained by adding n values constituting the second divided data. Processing method.

An intermediate image generation step of generating a first intermediate image obtained by extracting a component in the vicinity of a specific frequency band of the input image;
An intermediate image processing step that receives the first intermediate image as an input and generates a second intermediate image;
A first addition step of adding the input image and the second intermediate image;
The intermediate image processing step includes
A non-linear processing step of changing processing contents according to the pixels of the first intermediate image;
A high-frequency component image generation step for generating a high-frequency component image obtained by extracting only the high-frequency component of the image output by the nonlinear processing step;
A correction step of correcting the high-frequency component image,
The correction step includes
The pixel value of the high-frequency component image is divided into code data representing a sign of the pixel value and first divided data obtained by dividing the absolute value of the pixel value into n values (n is an integer of 2 or more). Splitting steps to
A divided data processing step of generating second divided data composed of n values in which at least one value is attenuated among n values constituting the first divided data;
And a synthesis step of outputting a value obtained by adding a code represented by the code data to a value obtained by adding n values constituting the second divided data. Processing method.

An intermediate for generating a first intermediate image composed of a horizontal intermediate image obtained by extracting components near a specific frequency band in the horizontal direction of the input image and a vertical intermediate image obtained by extracting components near a specific frequency band in the vertical direction An image generation step;
An intermediate image processing step that receives the first intermediate image as an input and generates a second intermediate image;
A first addition step of adding the input image and the second intermediate image;
The intermediate image processing step includes
A second addition step of adding the horizontal intermediate image and the vertical intermediate image;
A correction step of correcting the image output by the second addition step;
The correction step includes
A first pixel value obtained by dividing the pixel value of the image output by the second addition step into code data representing a sign of the pixel value and n absolute values of the pixel value (n is an integer of 2 or more). A division step for dividing into divided data;
A divided data processing step of generating second divided data composed of n values in which at least one value is attenuated among n values constituting the first divided data;
And a synthesis step of outputting a value obtained by adding a code represented by the code data to a value obtained by adding n values constituting the second divided data. Processing method.

An intermediate for generating a first intermediate image composed of a horizontal intermediate image obtained by extracting components near a specific frequency band in the horizontal direction of the input image and a vertical intermediate image obtained by extracting components near a specific frequency band in the vertical direction An image generation step;
An intermediate image processing step that receives the first intermediate image as an input and generates a second intermediate image;
A first addition step of adding the input image and the second intermediate image;
The intermediate image processing step includes
A horizontal non-linear processing step of changing the content of processing according to the pixels of the horizontal intermediate image;
A horizontal high-frequency component image generation step for generating a horizontal high-frequency component image obtained by extracting only the high-frequency component of the image output by the horizontal nonlinear processing step;
A vertical non-linear processing step of changing the content of processing according to the pixels of the vertical intermediate image;
A vertical high-frequency component image generation step for generating a vertical high-frequency component image obtained by extracting only the high-frequency component of the image output by the vertical nonlinear processing step;
A second addition step of adding the horizontal high frequency component image and the vertical high frequency component image;
A correction step of correcting the image output by the second addition step;
The correction step includes
A first pixel value obtained by dividing the pixel value of the image output by the second addition step into code data representing a code of the pixel value and n absolute values of the pixel value (n is an integer of 2 or more). A division step for dividing into divided data;
A divided data processing step of generating second divided data composed of n values in which at least one value is attenuated among n values constituting the first divided data;
And a synthesis step of outputting a value obtained by adding a code represented by the code data to a value obtained by adding n values constituting the second divided data. Processing method.

The image display apparatus for displaying an image processed by the image processing method according to any one of claims 12 to 18.