JPH11243496A - Contour emphasizing circuit - Google Patents
Contour emphasizing circuitInfo
- Publication number
- JPH11243496A JPH11243496A JP10059009A JP5900998A JPH11243496A JP H11243496 A JPH11243496 A JP H11243496A JP 10059009 A JP10059009 A JP 10059009A JP 5900998 A JP5900998 A JP 5900998A JP H11243496 A JPH11243496 A JP H11243496A
- Authority
- JP
- Japan
- Prior art keywords
- contour
- signal
- output
- component
- emphasis
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
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Abstract
Description
【０００１】[0001]
【発明の属する技術分野】本発明は、入力された輝度信
号から輪郭成分（高域周波数成分）を検出し、この検出
した輪郭成分を入力輝度信号に加算して輪郭強調された
輝度信号を出力する輪郭強調回路に関するものである。
入力輝度信号は、例えば複合カラー映像信号から分離さ
れたディジタルの輝度信号をいう。BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention detects a contour component (high frequency component) from an input luminance signal, and adds the detected contour component to an input luminance signal to output a contour-enhanced luminance signal. And a contour emphasizing circuit.
The input luminance signal is, for example, a digital luminance signal separated from the composite color video signal.
【０００２】[0002]
【従来の技術】高画質化を図るために用いられる輪郭強
調回路には、例えば、図６に示す輪郭強調回路（例え
ば、特開昭６２−２３９６７０の公開特許公報に開示さ
れた回路）や、図８に示す輪郭強調回路（例えば、平成
９年９月１７日発行、特許番号第２６５３８００号の特
許公報に開示された回路）が知られている。2. Description of the Related Art For example, a contour emphasizing circuit shown in FIG. 6 (for example, a circuit disclosed in Japanese Patent Laid-Open Publication No. 62-239670), for example, An outline emphasizing circuit shown in FIG. 8 (for example, a circuit disclosed in Japanese Patent Publication No. 2653800 issued on September 17, 1997) is known.
【０００３】図６に示す輪郭強調回路は、輪郭検出手段
１０、輪郭強調補正手段１１、遅延手段１２及び加算手
段１３からなり、輪郭検出手段１０によって入力端子１
４に入力した輝度信号から輪郭成分を検出し、輪郭強調
補正手段１１によって輪郭成分を非線形的に処理して輪
郭強調信号を作成し、加算手段１３によって遅延手段１
２で遅延させた入力輝度信号に輪郭強調信号を加算し、
出力端子１５から輪郭強調された輝度信号を出力する。
輪郭強調補正手段１１は、上限レベルＬｈ以上の信号を
クリップするアッパリミッタ１６と、下限レベルＬｌ以
下の信号をクリップするロアリミッタ１７とからなり、
図７に示すように、輪郭成分の上限レベルＬｈ以上の部
分をカットするとともに、下限レベル以下の部分をカッ
トした輪郭強調信号を加算手段１３に出力する。この輪
郭強調補正手段１１の作用によりレベル差の大きな輝度
信号の画像の輪郭を過度に強調しないようにしたもので
ある。The contour emphasizing circuit shown in FIG. 6 comprises a contour detecting means 10, a contour emphasizing correcting means 11, a delaying means 12 and an adding means 13, and the input terminal 1 is controlled by the contour detecting means 10.
The edge component is detected from the luminance signal input to the input unit 4, the edge component is nonlinearly processed by the edge enhancement correction unit 11 to generate an edge enhancement signal, and the addition unit 13 delays the delay unit 1.
Adding an edge emphasis signal to the input luminance signal delayed by 2;
The output terminal 15 outputs a luminance signal whose outline is emphasized.
The contour emphasis correction means 11 includes an upper limiter 16 for clipping a signal equal to or higher than the upper limit level Lh and a lower limiter 17 for clipping a signal equal to or lower than the lower limit level Ll.
As shown in FIG. 7, a portion above the upper limit level Lh of the contour component is cut, and a contour emphasizing signal obtained by cutting a portion below the lower limit level is output to the adding means 13. By the operation of the contour emphasis correction means 11, the contour of the image of the luminance signal having a large level difference is not excessively emphasized.
【０００４】図８に示す輪郭強調回路は、輪郭検出回路
２０、非線形回路２１、遅延回路２２及び加算回路２３
からなり、輪郭検出回路２０によって入力端子２４に入
力した輝度信号から輪郭成分を検出し、非線形回路２１
によって輪郭成分を非線形的に処理して輪郭強調信号を
作成し、加算回路２３によって遅延回路２２で遅延させ
た入力輝度信号に輪郭強調信号を加算し、出力端子２５
から輪郭強調された輝度信号を出力する。非線形回路２
１は低レベル抑圧回路２６と大レベル抑圧回路２７から
なり、低レベル抑圧回路２６に、図９の（ａ）に示すよ
うに入力信号レベルの基準レベルＥ2（絶対値）以下を
抑圧する入出力特性をもたせ、大レベル抑圧回路２７
に、同図の（ｂ）に示すように入力信号レベルの基準レ
ベルＥ1（絶対値）以上を抑圧する入出力特性をもた
せ、非線形回路２１に同図の（ｃ）に示すような総合入
出力特性をもたせる。このため、非線形回路２１に導か
れた輪郭成分は、その大レベル部（絶対値Ｅ1以上）及
び小レベル部（絶対値Ｅ2以下）が抑圧されるので、Ｓ
／Ｎ比劣化を殆ど生じさせずに、輪郭変化の大きな部分
の過度の輪郭強調をなくすようにしたものである。The contour emphasizing circuit shown in FIG. 8 comprises a contour detecting circuit 20, a nonlinear circuit 21, a delay circuit 22, and an adding circuit 23.
The contour detection circuit 20 detects a contour component from the luminance signal input to the input terminal 24,
The contour component is nonlinearly processed to generate a contour emphasizing signal, and the adding circuit 23 adds the contour emphasizing signal to the input luminance signal delayed by the delay circuit 22, and the output terminal 25.
Output a luminance signal whose outline is emphasized. Nonlinear circuit 2
Reference numeral 1 denotes a low-level suppression circuit 26 and a large-level suppression circuit 27. The low-level suppression circuit 26 has an input signal for suppressing an input signal level below a reference level E 2 (absolute value) as shown in FIG. The output characteristics are provided, and the large-level suppression circuit 27 is provided.
In addition, as shown in FIG. 3B, the input / output characteristic for suppressing the input signal level to be equal to or higher than the reference level E 1 (absolute value) is provided. Give output characteristics. Therefore, the contour component guided to the non-linear circuit 21, so that the large level portion (the absolute value E 1 or higher) and the small-level part (absolute value E 2 or less) is suppressed, S
The present invention is intended to eliminate excessive contour emphasis in a portion where a contour change is large, with almost no deterioration of the / N ratio.
【０００５】[0005]
【発明が解決しようとする課題】しかしながら、図６及
び図８に示した輪郭強調回路は、輪郭検出部１０、２０
で検出した輪郭成分の大レベル部を抑圧して出力してい
るので、輪郭変化の大きな部分の過度の輪郭強調をなく
すことはできるが、輪郭検出部１０、２０で検出した輪
郭成分の小レベル部をそのまま又は抑圧して出力してい
るので、輪郭変化の小さな部分の輪郭強調が不足すると
いう問題点があった。However, the contour emphasizing circuits shown in FIGS.
Since the large-level portion of the contour component detected in step (1) is suppressed and output, excessive contour emphasis in a portion where the contour change is large can be eliminated. Since the portion is output as it is or suppressed, there is a problem that the contour emphasis on a portion having a small contour change is insufficient.
【０００６】本発明は、上述の問題点に鑑みてなされた
もので、輪郭変化の大きな部分の過度の輪郭強調をなく
すとともに、輪郭変化の小さな部分の輪郭強調不足を改
善することのできる輪郭強調回路を提供することを目的
とするものである。SUMMARY OF THE INVENTION The present invention has been made in view of the above-described problems, and it is an object of the present invention to eliminate excessive contour enhancement in a portion having a large contour change and to improve insufficient contour enhancement in a portion having a small contour change. It is intended to provide a circuit.
【０００７】[0007]
【課題を解決するための手段】請求項１の発明は、入力
された輝度信号から輪郭成分を検出する輪郭検出手段
と、この輪郭検出手段で検出した輪郭成分をその振幅に
応じて非線形に処理して輪郭強調信号を出力する非線形
処理手段と、この非線形処理手段から出力する輪郭強調
信号を入力輝度信号に加算して輪郭強調された輝度信号
を出力する加算手段とを具備し、前記非線形処理手段に
よる非線形特性を、輪郭成分の振幅の絶対値が設定値よ
りも大きい信号については抑圧特性とし、輪郭成分の振
幅の絶対値が設定値よりも小さい信号については強調特
性とする。輪郭検出手段で検出した輪郭成分は、非線形
処理手段による非線形処理によって、輪郭変化の大きな
部分は抑圧特性（例えば飽和特性）による抑圧された輪
郭強調信号となり、輪郭変化の小さな部分は強調特性
（例えば傾きが１以上の比例特性）による強調された輪
郭強調信号となるので、輪郭変化の大きな部分の過度の
輪郭強調をなくすとともに、輪郭変化の小さな部分の輪
郭強調不足を改善することができる。According to a first aspect of the present invention, there is provided a contour detecting means for detecting a contour component from an input luminance signal, and a non-linear processing of the contour component detected by the contour detecting means in accordance with its amplitude. A nonlinear processing means for outputting a contour-enhanced signal to the input luminance signal and outputting a contour-enhanced luminance signal by adding the contour-enhanced signal output from the nonlinear processing means to the input luminance signal. The nonlinear characteristic of the means is a suppression characteristic for a signal whose absolute value of the amplitude of the contour component is larger than a set value, and an enhanced characteristic for a signal whose absolute value of the amplitude of the contour component is smaller than the set value. The contour component detected by the contour detecting means is subjected to non-linear processing by the non-linear processing means, so that a portion having a large change in contour becomes a contour emphasis signal suppressed by a suppression characteristic (for example, a saturation characteristic), and a portion having a small contour change is subjected to an emphasis characteristic (for example, Since the edge enhancement signal is an edge-enhanced signal enhanced by a proportional characteristic having a slope of 1 or more, it is possible to eliminate excessive edge enhancement in a portion having a large edge change and to improve insufficient edge enhancement in a portion having a small edge change.
【０００８】請求項２の発明は、請求項１の発明におい
て、非線形処理手段の構成を簡単にするために、非線形
処理手段を、輪郭検出手段で検出した輪郭成分を絶対値
に変換して出力する絶対値変換回路と、この絶対値変換
回路の出力に１より大きな係数を掛けて出力する乗算器
と、絶対値変換回路の出力と設定値とを比較する比較器
と、この比較器の比較出力に基づいて乗算器の出力と設
定値の一方を選択して出力するセレクタと、このセレク
タの出力に輪郭成分の正負に応じた符号をつけ輪郭強調
信号として出力する符号器とで構成する。According to a second aspect of the present invention, in order to simplify the configuration of the nonlinear processing means, the nonlinear processing means converts the contour component detected by the contour detecting means into an absolute value and outputs the result. Absolute value conversion circuit, a multiplier for multiplying the output of the absolute value conversion circuit by a coefficient greater than 1, and outputting the result, a comparator for comparing the output of the absolute value conversion circuit with a set value, and a comparison of the comparator It comprises a selector for selecting and outputting one of the output of the multiplier and the set value based on the output, and an encoder for adding a sign according to the sign of the contour component to the output of the selector and outputting it as a contour emphasis signal.
【０００９】請求項３の発明は、請求項１の発明におい
て、非線形処理手段による非線形処理の設計の自由度を
高くするために、非線形処理手段を、輪郭検出手段で検
出した輪郭成分をアドレスの入力とし、輪郭強調信号を
アドレスの内容として出力するルックアップテーブルで
構成し、このルックアップテーブルの入出力特性を非線
形特性曲線で形成し、この非線形特性曲線を、輪郭成分
の振幅の絶対値が設定値よりも大きい信号については接
線の傾きが１より小さくなり、輪郭成分の振幅の絶対値
が設定値よりも小さい信号については接線の傾きが１よ
り大きくなる特性曲線とする。According to a third aspect of the present invention, in order to increase the degree of freedom in designing the nonlinear processing by the nonlinear processing means, the nonlinear processing means may be configured such that the contour component detected by the contour detecting means is used as an address of the address. It is composed of a look-up table that takes an input and outputs a contour emphasis signal as the contents of an address, and the input / output characteristics of the look-up table are formed by a nonlinear characteristic curve. For a signal larger than the set value, the slope of the tangent is smaller than 1, and for a signal whose absolute value of the amplitude of the contour component is smaller than the set value, the characteristic curve is such that the slope of the tangent is larger than 1.
【００１０】請求項４の発明は、請求項１、２又は３の
発明において、垂直方向及び水平方向の輪郭強調ができ
るようにするために、輪郭検出手段を垂直方向の輪郭成
分を検出する垂直輪郭検出部と水平方向の輪郭成分を検
出する水平輪郭検出部で構成し、垂直方向の輪郭成分と
水平方向の輪郭成分とを加算して非線形処理手段へ出力
する輪郭成分加算器を設ける。According to a fourth aspect of the present invention, in the first, second or third aspect of the present invention, the contour detecting means detects a vertical contour component to detect a vertical contour component so that vertical and horizontal contour enhancement can be performed. A contour component adder is provided which comprises a contour detecting section and a horizontal contour detecting section for detecting a horizontal contour component, and adds a vertical contour component and a horizontal contour component and outputs the result to the nonlinear processing means.
【００１１】請求項５の発明は、請求項４の発明におい
て、非線形処理手段及び加算手段で扱う信号の振幅を小
さくするために、輪郭成分加算器と非線形処理手段の間
に、輪郭成分加算器から出力する輪郭成分を所定の上限
レベル及び下限レベルでクリップして非線形処理手段へ
出力するリミッタを設ける。According to a fifth aspect of the present invention, in the fourth aspect of the present invention, a contour component adder is provided between the contour component adder and the non-linear processing means to reduce the amplitude of a signal handled by the non-linear processing means and the adding means. And a limiter for clipping the contour component output from the non-linear processing means at predetermined upper and lower levels.
【００１２】請求項６の発明は、請求項１、２又は３の
発明において、垂直方向及び水平方向の輪郭強調を個別
に制御できるようにするために、輪郭検出手段を垂直輪
郭検出部と水平輪郭検出部で構成し、非線形処理手段
を、垂直輪郭検出部で検出した輪郭成分に非線形処理を
して垂直方向の輪郭強調信号を出力する第１非線形処理
部と、水平輪郭検出部で検出した輪郭成分に非線形処理
をして水平方向の輪郭強調信号を出力する第２非線形処
理部とで構成し、第１非線形処理部の出力する輪郭強調
信号と第２非線形処理部の出力する輪郭強調信号を加算
して加算手段へ出力する輪郭強調加算器を設ける。According to a sixth aspect of the present invention, in the first, second or third aspect of the present invention, the contour detecting means includes a vertical contour detecting section and a horizontal contour detecting section so that the vertical and horizontal contour enhancement can be individually controlled. A nonlinear processing unit configured to perform nonlinear processing on a contour component detected by the vertical contour detecting unit and output a vertical contour emphasis signal; and a non-linear processing unit. A second nonlinear processing section for performing nonlinear processing on a contour component and outputting a horizontal contour enhancement signal, wherein a contour enhancement signal output from the first nonlinear processing section and a contour enhancement signal output from the second nonlinear processing section are provided. And an edge emphasis adder that outputs the result to the addition means.
【００１３】請求項７の発明は、請求項６の発明におい
て、加算手段で加算する輪郭強調信号の振幅を小さくす
るために、輪郭強調加算器と加算手段の間に、輪郭強調
加算器から出力する輪郭強調信号を所定の上限レベル及
び下限レベルでクリップして加算手段へ出力するリミッ
タを設ける。According to a seventh aspect of the present invention, in the sixth aspect, an output from the contour emphasis adder is provided between the contour emphasis adder and the addition means to reduce the amplitude of the contour emphasis signal added by the addition means. A limiter is provided for clipping the contour emphasizing signal at a predetermined upper limit level and lower limit level and outputting the clipped signal to the adding means.
【００１４】[0014]
【発明の実施の形態】以下、本発明の実施の形態例を図
面により説明する。図１は本発明による輪郭強調回路の
一実施形態例を示すものである。図１において、３０は
輪郭検出手段の一例としての水平輪郭検出部、３２は非
線形処理部、３４は遅延部、３６は加算部である。DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, embodiments of the present invention will be described with reference to the drawings. FIG. 1 shows an embodiment of an outline emphasizing circuit according to the present invention. In FIG. 1, reference numeral 30 denotes a horizontal contour detecting unit as an example of a contour detecting unit, 32 denotes a non-linear processing unit, 34 denotes a delay unit, and 36 denotes an adding unit.
【００１５】前記水平輪郭検出部３０は、入力端子３１
に入力した輝度信号Ｙ（例えばディジタル信号）を順次
１ドット分遅延させる遅延器３８、４０と、入力端子３
１に入力した輝度信号Ｙに遅延器４０の出力信号を加算
する加算器４２と、この加算器４２の出力信号に−１／
４を掛けて出力する乗算器４４と、遅延器３８の出力信
号に１／２を掛けて出力する乗算器４６と、乗算器４４
の出力信号と乗算器４６の出力信号を加算する加算器４
８とからなり、基準画素の左右に隣接する画素から基準
画素の水平方向の輪郭成分ＨＥを検出して出力する。The horizontal contour detector 30 has an input terminal 31
And delay units 38 and 40 for sequentially delaying the luminance signal Y (for example, a digital signal) inputted to the input terminal 3 by one dot.
An adder 42 for adding the output signal of the delay unit 40 to the luminance signal Y input to 1;
A multiplier 44 for multiplying the output signal by 4 and outputting the output signal of the delay unit 38;
Adder 4 that adds the output signal of the multiplier 46 and the output signal of the multiplier 46
8, and detects and outputs a horizontal contour component HE of the reference pixel from pixels adjacent to the left and right of the reference pixel.
【００１６】前記非線形処理部３２は、前記水平輪郭検
出部３０で検出した輪郭成分ＨＥを絶対値に変換して出
力する絶対値変換回路５０と、この絶対値変換回路５０
の出力に１より大きな係数（例えば１．２）を掛けて出
力する乗算器５２と、前記絶対値変換回路５０の出力と
設定値Ｓ（例えば、１０進数表示で５０）とを比較する
比較器５４と、この比較器５４の比較出力（ＳＥＬ端子
への入力）に基づいて前記乗算器５２の出力（Ａ端子へ
の入力）と設定値Ｓ（Ｂ端子への入力）の一方を選択し
て出力（Ｙ端子から出力）するセレクタ５６と、このセ
レクタ５６の出力に前記輪郭成分ＨＥの正負に応じた符
号をつけ輪郭強調信号ＨＥｅとして出力する符号器５８
とからなり、前記水平輪郭検出部３０で検出した輪郭成
分ＨＥを、その振幅に応じて非線形に処理した輪郭強調
信号ＨＥｅを出力する。The nonlinear processing section 32 converts the contour component HE detected by the horizontal contour detection section 30 into an absolute value and outputs the absolute value.
A multiplier 52 that multiplies the output of the absolute value conversion circuit by a coefficient (for example, 1.2) larger than 1 and outputs the result, and a comparator that compares the output of the absolute value conversion circuit 50 with a set value S (for example, 50 in decimal notation). 54 and one of the output of the multiplier 52 (input to the A terminal) and the set value S (input to the B terminal) based on the comparison output of the comparator 54 (input to the SEL terminal). A selector 56 for outputting (outputting from the Y terminal), and an encoder 58 for adding a sign to the output of the selector 56 in accordance with the sign of the contour component HE and outputting the sign as a contour emphasis signal HEe
And outputs a contour emphasis signal HEe obtained by nonlinearly processing the contour component HE detected by the horizontal contour detection unit 30 in accordance with the amplitude thereof.
【００１７】前記遅延部３４は、前記入力端子３１に入
力した輝度信号Ｙを１ドット分遅延させ、前記加算部３
６は、前記遅延部３４で遅延させた入力輝度信号Ｙと、
前記非線形処理部３２から出力する輪郭強調信号ＨＥｅ
とを加算し、出力端子３７へ輪郭強調された輝度信号
（Ｙ＋ＨＥｅ）を出力する。The delay section 34 delays the luminance signal Y input to the input terminal 31 by one dot, and
6 is an input luminance signal Y delayed by the delay unit 34;
The contour emphasis signal HEe output from the nonlinear processing unit 32
And outputs a luminance signal (Y + HEe) whose outline is emphasized to the output terminal 37.
【００１８】つぎに図１の作用を図２（ａ）を併用して
説明する。 （イ）水平輪郭検出部３０によって、入力端子３１に入
力した輝度信号Ｙ（例えば、８ビットの信号）から水平
方向の輪郭成分ＨＥ（例えば、１０進数表示で−１２８
〜１２７）が検出され、検出された輪郭成分ＨＥは非線
形処理部３２に入力する。Next, the operation of FIG. 1 will be described with reference to FIG. (A) The horizontal contour detection unit 30 converts a luminance component Y (for example, an 8-bit signal) input to the input terminal 31 into a horizontal contour component HE (for example, -128 in decimal notation).
To 127) are detected, and the detected contour component HE is input to the nonlinear processing unit 32.
【００１９】（ロ）非線形処理部３２では、入力した輪
郭成分ＨＥの振幅の絶対値を設定値Ｓと比較し、その大
小に基づいて次ぎのような非線形処理を行う。説明の便
宜上、設定値Ｓが５０（１０進数表示）の場合について
説明する。入力した輪郭成分ＨＥは、絶対値変換回路５
０で絶対値に変換され、乗算器５２で１より大きな係数
（例えば１．２）を掛けられ、セレクタ５６のＡ端子に
入力する。設定値Ｓはセレクタ５６のＢ端子に入力す
る。絶対値変換回路５０で絶対値に変換された輪郭成分
ＨＥと設定値Ｓとが比較器５４で比較され、前者が後者
（設定値Ｓ）より大きいときにはＨレベル信号がセレク
タ５６のＳＥＬ端子に入力しＢ端子入力を選択してＹ端
子から出力し、前者が後者より小さいときにはＬレベル
信号がセレクタ５６のＳＥＬ端子に入力しＡ端子入力を
選択してＹ端子から出力する。セレクタ５６のＹ端子か
ら出力した信号は、入力した輪郭成分ＨＥの正負に応じ
て符号器５８で符号付けされる。このため、図２の
（ａ）に示すような、輪郭成分ＨＥの入力に対して非線
形処理された輪郭強調信号ＨＥｅが、符号器５８から加
算部３６へ出力する。図２の（ａ）において点線は傾き
が１の比例特性を表す。(B) The nonlinear processing section 32 compares the absolute value of the amplitude of the input contour component HE with the set value S, and performs the following nonlinear processing based on the magnitude. For convenience of explanation, a case where the set value S is 50 (decimal notation) will be described. The input contour component HE is converted to an absolute value conversion circuit 5.
The value is converted to an absolute value by 0, multiplied by a coefficient (for example, 1.2) larger than 1 by the multiplier 52, and input to the A terminal of the selector 56. The set value S is input to the B terminal of the selector 56. The contour value HE converted into the absolute value by the absolute value conversion circuit 50 is compared with the set value S by the comparator 54. When the former is larger than the latter (the set value S), an H level signal is input to the SEL terminal of the selector 56. Then, the B terminal input is selected and output from the Y terminal. When the former is smaller than the latter, an L level signal is input to the SEL terminal of the selector 56, the A terminal input is selected and output from the Y terminal. The signal output from the Y terminal of the selector 56 is encoded by the encoder 58 in accordance with the sign of the input contour component HE. For this reason, as shown in FIG. 2A, a contour emphasis signal HEe obtained by nonlinearly processing the input of the contour component HE is output from the encoder 58 to the adding unit 36. In FIG. 2A, a dotted line indicates a proportional characteristic having a slope of 1.
【００２０】（ハ）符号器５８から出力した輪郭強調信
号ＨＥｅと、入力端子３１に入力し遅延部３４で１ドッ
ト分遅延した輝度信号Ｙとは加算部３６で加算され、輪
郭強調された輝度信号（Ｙ＋ＨＥｅ）として出力端子３
７から出力する。この出力端子３７から出力する信号に
含まれる輪郭強調信号ＨＥｅは、図２の（ａ）に示すよ
うに、輪郭成分ＨＥの絶対値が設定値Ｓ（＝５０）より
大きい範囲では一定の飽和値６０で抑圧され、輪郭成分
ＨＥの絶対値が設定値Ｓ（＝５０）より小さい範囲では
乗算器５２の係数倍（例えば１．２）に強調されている
ので、輪郭変化の大きな部分の過度の輪郭強調をなくす
とともに、輪郭変化の小さな部分の輪郭強調不足を改善
することができる。(C) The outline emphasis signal HEe output from the encoder 58 and the luminance signal Y input to the input terminal 31 and delayed by one dot by the delay unit 34 are added by the addition unit 36, and the luminance whose outline is emphasized is added. Output terminal 3 as signal (Y + HEe)
7 to output. As shown in FIG. 2A, the contour enhancement signal HEe included in the signal output from the output terminal 37 has a constant saturation value when the absolute value of the contour component HE is larger than the set value S (= 50). In the range in which the absolute value of the outline component HE is smaller than the set value S (= 50), it is emphasized by the factor of the multiplier 52 (for example, 1.2). In addition to eliminating contour emphasis, it is possible to improve insufficient contour emphasis at a portion where the contour change is small.
【００２１】図１の実施形態例では、非線形処理部の設
定値Ｓが５０、乗算器で掛ける係数が１．２の場合につ
いて説明したが、本発明はこれに限るものでなく、図２
の（ｂ）に示すように、設定値が３０、乗算器で掛ける
係数が１．６の場合についても利用することができる。In the embodiment of FIG. 1, the case where the setting value S of the nonlinear processing section is 50 and the coefficient multiplied by the multiplier is 1.2 has been described. However, the present invention is not limited to this.
As shown in (b), it is also possible to use the case where the set value is 30 and the coefficient multiplied by the multiplier is 1.6.
【００２２】前記実施形態例では、非線形処理部の非線
形処理特性は、輪郭成分ＨＥの絶対値が設定値Ｓ（例え
ば５０）より大きい範囲では一定の飽和値（例えば６
０）となり、輪郭成分ＨＥの絶対値が設定値Ｓより小さ
い範囲では１より大きな係数を掛けた直線となるように
したが、本発明はこれに限るものでなく、輪郭成分ＨＥ
の振幅の絶対値が設定値Ｓよりも大きい信号については
抑圧特性となり、輪郭成分ＨＥの振幅の絶対値が設定値
Ｓよりも小さい信号については強調特性となるものにつ
いて利用することができる。In the above-described embodiment, the nonlinear processing characteristic of the nonlinear processing unit is such that a constant saturation value (for example, 6) is set in a range where the absolute value of the contour component HE is larger than the set value S (for example, 50).
0), and in a range where the absolute value of the contour component HE is smaller than the set value S, a straight line multiplied by a coefficient larger than 1 is used. However, the present invention is not limited to this, and the contour component HE is not limited to this.
A signal having an absolute value of the amplitude greater than the set value S has a suppression characteristic, and a signal having an absolute value of the amplitude of the contour component HE smaller than the set value S has an enhancement characteristic.
【００２３】例えば、図１の非線形処理部３２をＬＵＴ
（ルックアップテーブル）で置換するとともに、その非
線形特性を図３に示すような特性曲線としたなものにつ
いても本発明を利用することができる。すなわち、輪郭
検出部３０で検出した輪郭成分ＨＥをアドレスの入力と
し、輪郭強調信号ＨＥｅをアドレスの内容として出力す
るＬＵＴとし、このＬＵＴの入出力特性を、図３に示す
ように、輪郭成分ＨＥの振幅の絶対値が設定値Ｓよりも
大きい信号については接線の傾きが１より小さくなり、
輪郭成分ＨＥの振幅の絶対値が設定値Ｓよりも小さい信
号については接線の傾きが１より大きくなる非線形特性
曲線とする。これによって、輪郭変化の大きな部分の過
度の輪郭強調をなくすとともに、輪郭変化の小さな部分
の輪郭強調不足を改善することができる。図３におい
て、点線は傾きが１の比例特性を表し、１点鎖線は非線
形特性曲線に接する接線のうちの傾きが１の接線を表
す。For example, the nonlinear processing unit 32 shown in FIG.
The present invention can be applied to a case where the nonlinear characteristic is replaced by a characteristic curve as shown in FIG. That is, the contour component HE detected by the contour detection unit 30 is used as an address input, and an LUT for outputting the contour emphasis signal HEe as the content of the address. The input / output characteristics of this LUT are shown in FIG. For a signal whose absolute value of the amplitude is larger than the set value S, the slope of the tangent becomes smaller than 1;
A signal whose absolute value of the amplitude of the contour component HE is smaller than the set value S is a non-linear characteristic curve in which the tangent slope is larger than 1. As a result, it is possible to eliminate excessive contour enhancement in a portion having a large contour change and improve insufficient contour enhancement in a portion having a small contour change. In FIG. 3, a dotted line indicates a proportional characteristic having a slope of 1, and a dashed line indicates a tangent having a slope of 1 among tangents tangent to the nonlinear characteristic curve.
【００２４】前記実施形態例では輪郭検出手段が水平輪
郭検出部の場合について説明したが、本発明はこれに限
るものでなく、垂直方向及び水平方向の輪郭強調ができ
るようにするために、図４に示すように、輪郭検出手段
が垂直輪郭検出部と水平輪郭検出部で構成された場合に
ついても本発明を利用することができる。In the above embodiment, the case where the contour detecting means is a horizontal contour detecting section has been described. However, the present invention is not limited to this. As shown in FIG. 4, the present invention can be applied to a case where the contour detecting means is composed of a vertical contour detecting section and a horizontal contour detecting section.
【００２５】図４に示した実施形態例では、入力端子３
１と水平輪郭検出部３０の間に垂直輪郭検出部６０を結
合し、この垂直輪郭検出部６０で検出した垂直方向の輪
郭成分ＶＥを１ドット分遅延させる遅延器６２を結合
し、この遅延器６２から出力した輪郭成分ＶＥと水平輪
郭検出部３０で検出した水平方向の輪郭成分ＨＥとを加
算して合成輪郭成分ＧＥを出力する輪郭成分加算器６４
を設け、この輪郭成分加算器６４から出力する合成輪郭
成分ＧＥ（例えば−２５６〜２５４）を所定の上限レベ
ル（例えば１２７）及び下限レベル（例えば−１２８）
でクリップし、所定範囲（例えば−１２８〜１２７）に
制限して非線形処理部３２へ出力するリミッタ６６を設
ける。In the embodiment shown in FIG. 4, the input terminal 3
1 and a horizontal contour detector 30, a vertical contour detector 60 is coupled, and a delay 62 for delaying the vertical contour component VE detected by the vertical contour detector 60 by one dot is coupled. A contour component adder 64 that adds the contour component VE output from the horizontal component 62 and the horizontal contour component HE detected by the horizontal contour detector 30 to output a composite contour component GE.
The composite contour component GE (for example, -256 to 254) output from the contour component adder 64 is converted into a predetermined upper limit level (for example, 127) and a lower limit level (for example, -128).
Is provided, and a limiter 66 is provided which limits the output to a predetermined range (for example, -128 to 127) and outputs it to the nonlinear processing unit 32.
【００２６】前記垂直輪郭検出部６０は、入力端子３１
に入力した輝度信号Ｙを順次１ライン分遅延させる遅延
器６８、７０と、入力端子３１に入力した輝度信号Ｙに
遅延器７０の出力信号を加算する加算器７２と、この加
算器７２の出力信号に−１／４を掛けて出力する乗算器
７４と、遅延器６８の出力信号に１／２を掛けて出力す
る乗算器７６と、乗算器７４の出力信号と乗算器７６の
出力信号を加算する加算器７８とからなり、基準画素の
上下に隣接する画素から基準画素の垂直方向の輪郭成分
ＶＥを検出して出力する図４において、遅延器６８、３
８が図１の遅延器３４に相当する。The vertical contour detecting section 60 has an input terminal 31
, Delay units 68 and 70 for sequentially delaying the input luminance signal Y by one line, an adder 72 for adding the output signal of the delay unit 70 to the luminance signal Y input to the input terminal 31, and an output of the adder 72. A multiplier 74 that multiplies the signal by − ／ and outputs the same, a multiplier 76 that multiplies the output signal of the delay unit 68 by half and outputs the resultant signal, and outputs the output signal of the multiplier 74 and the output signal of the multiplier 76 In FIG. 4, the adder 78 includes an adder 78 for adding and detecting a vertical contour component VE of the reference pixel from pixels adjacent above and below the reference pixel.
8 corresponds to the delay unit 34 in FIG.
【００２７】図４の実施形態例では、垂直方向の輪郭成
分ＶＥと水平方向の輪郭成分ＨＥを加算した合成輪郭成
分ＧＥに対して非線形処理を行った場合について説明し
たが、本発明はこれに限るものでなく、垂直方向と水平
方向の輪郭強調を個別に制御できるようにしたものにつ
いても利用することができる。例えば、図５に示すよう
に、垂直方向の輪郭成分ＶＥに対して非線形処理をして
垂直方向の輪郭強調信号ＶＥｅを出力する第１非線形処
理部３２ｖと、水平方向の輪郭成分ＨＥに非線形処理を
して水平方向の輪郭強調信号ＨＥｅを出力する第２非線
形処理部３２ｈと、第１非線形処理部３２ｖの出力する
輪郭強調信号ＶＥｅと第２非線形処理部３２ｈの出力す
る輪郭強調信号ＨＥｅを加算する輪郭強調加算器８０と
を設け、輪郭強調加算器８０の出力信号をリミッタ６６
を介して加算部３６へ出力する。In the embodiment of FIG. 4, a case has been described in which nonlinear processing is performed on a composite contour component GE obtained by adding a vertical contour component VE and a horizontal contour component HE. The present invention is not limited to this, and the present invention can also be applied to one in which vertical and horizontal contour enhancement can be individually controlled. For example, as shown in FIG. 5, a first nonlinear processing unit 32v that performs nonlinear processing on a vertical contour component VE and outputs a vertical contour enhancement signal VEe, and nonlinear processing on a horizontal contour component HE. And a second nonlinear processing unit 32h that outputs a horizontal edge enhancement signal HEe, and adds the edge enhancement signal VEe output from the first nonlinear processing unit 32v and the edge enhancement signal HEe output from the second nonlinear processing unit 32h. And an output signal of the edge enhancement adder 80 is provided to a limiter 66.
To the adder 36 via
【００２８】図４及び図５の実施形態例では、リミッタ
を設けて後段の回路（図４では非線形処理部３２及び加
算部３６、図５では加算部３６）で扱う信号の振幅を小
さくするようにしたが、本発明はこれに限るものでな
く、リミッタを省略したものについても利用することが
できる。In the embodiments of FIGS. 4 and 5, a limiter is provided to reduce the amplitude of a signal handled by a subsequent circuit (the nonlinear processing unit 32 and the adding unit 36 in FIG. 4, and the adding unit 36 in FIG. 5). However, the present invention is not limited to this, and can also be used with one in which the limiter is omitted.
【００２９】[0029]
【発明の効果】請求項１の発明は、輪郭検出手段、非線
形処理手段及び加算手段を具備し、非線形処理手段によ
る非線形特性を、輪郭成分の振幅の絶対値が設定値より
も大きい信号については抑圧特性とし、輪郭成分の振幅
の絶対値が設定値よりも小さい信号については強調特性
としたので、非線形処理手段によって、輪郭検出手段で
検出した輪郭成分のうち、輪郭変化の大きな部分は抑圧
特性（例えば飽和特性）による抑圧された輪郭強調信号
となり、輪郭変化の小さな部分は強調特性（例えば傾き
が１以上の比例特性）による強調された輪郭強調信号と
なるので、輪郭変化の大きな部分の過度の輪郭強調をな
くすとともに、輪郭変化の小さな部分の輪郭強調不足を
改善することができる。According to the first aspect of the present invention, there is provided a contour detecting means, a non-linear processing means, and an adding means. Signals whose absolute value of the amplitude of the contour component is smaller than the set value are emphasized characteristics. Therefore, a portion of the contour component detected by the contour detecting means that has a large change in the contour is suppressed by the nonlinear processing means. (E.g., a saturation characteristic), the contour enhancement signal is suppressed, and a small change in the contour is a contour enhancement signal enhanced by the enhancement characteristic (e.g., a proportional characteristic having a slope of 1 or more). Can be eliminated, and insufficient contour enhancement at a portion where the contour change is small can be improved.
【００３０】請求項２の発明は、請求項１の発明におい
て、非線形処理手段を、輪郭検出手段で検出した輪郭成
分を絶対値に変換して出力する絶対値変換回路と、この
絶対値変換回路の出力に１より大きな係数を掛けて出力
する乗算器と、絶対値変換回路の出力と設定値とを比較
する比較器と、この比較器の比較出力に基づいて乗算器
の出力と設定値の一方を選択して出力するセレクタと、
このセレクタの出力に輪郭成分の正負に応じた符号をつ
け輪郭強調信号として出力する符号器とで構成したの
で、非線形処理手段の構成を簡単にすることができる。According to a second aspect of the present invention, in the first aspect of the present invention, the non-linear processing means converts the contour component detected by the contour detecting means into an absolute value and outputs the absolute value. , A multiplier that multiplies the output of the multiplier by a coefficient greater than 1, outputs a comparator that compares the output of the absolute value conversion circuit with a set value, and outputs the output of the multiplier and the set value based on the comparison output of the comparator. A selector for selecting and outputting one,
Since the output of the selector is composed of an encoder that attaches a sign according to the sign of the contour component and outputs the signal as a contour emphasizing signal, the configuration of the nonlinear processing means can be simplified.
【００３１】請求項３の発明は、請求項１の発明におい
て、非線形処理手段を、輪郭検出手段で検出した輪郭成
分をアドレスの入力とし、輪郭強調信号をアドレスの内
容として出力するルックアップテーブルで構成し、この
ルックアップテーブルの入出力特性を非線形特性曲線で
形成し、この非線形特性曲線を、輪郭成分の振幅の絶対
値が設定値よりも大きい信号については接線の傾きが１
より小さくなり、輪郭成分の振幅の絶対値が設定値より
も小さい信号については接線の傾きが１より大きくなる
特性曲線としたので、非線形処理手段による非線形処理
の設計の自由度を高くすることができる。According to a third aspect of the present invention, in the first aspect of the present invention, the non-linear processing means is a look-up table which outputs a contour component detected by the contour detecting means as an address and outputs a contour emphasis signal as the contents of the address. The input / output characteristics of the look-up table are formed by a nonlinear characteristic curve, and the nonlinear characteristic curve has a tangent slope of 1 for a signal whose absolute value of the amplitude of the contour component is larger than a set value.
Since the characteristic curve is smaller and the absolute value of the amplitude of the contour component is smaller than the set value, the characteristic curve is such that the slope of the tangent is larger than 1. Therefore, the degree of freedom in designing the nonlinear processing by the nonlinear processing means can be increased. it can.
【００３２】請求項４の発明は、請求項１、２又は３の
発明において、輪郭検出手段を垂直輪郭検出部と水平輪
郭検出部で構成し、垂直輪郭検出部で検出した輪郭成分
と水平輪郭検出部で検出した輪郭成分とを加算して非線
形処理手段へ出力する輪郭成分加算器を設けたので、垂
直方向及び水平方向の輪郭強調を行うことができる。According to a fourth aspect of the present invention, in the first, second or third aspect, the contour detecting means comprises a vertical contour detecting section and a horizontal contour detecting section, and the contour component detected by the vertical contour detecting section and the horizontal contour are detected. Since the contour component adder that adds the contour component detected by the detection unit and outputs the result to the non-linear processing means is provided, contour enhancement in the vertical direction and the horizontal direction can be performed.
【００３３】請求項５の発明は、請求項４の発明におい
て、輪郭成分加算器と非線形処理手段の間に、輪郭成分
加算器から出力する輪郭成分を所定の上限レベル及び下
限レベルでクリップして非線形処理手段へ出力するリミ
ッタを設けたので、非線形処理手段及び加算手段で扱う
信号の振幅を小さくして回路構成を簡単にすることがで
きる。According to a fifth aspect of the present invention, in the fourth aspect, the contour component output from the contour component adder is clipped between the contour component adder and the non-linear processing means at predetermined upper and lower levels. Since the limiter for outputting to the non-linear processing means is provided, the amplitude of the signal handled by the non-linear processing means and the adding means can be reduced to simplify the circuit configuration.
【００３４】請求項６の発明は、請求項１、２又は３の
発明において、輪郭検出手段を垂直輪郭検出部と水平輪
郭検出部で構成し、非線形処理手段を、垂直輪郭検出部
で検出した輪郭成分に非線形処理をして垂直方向の輪郭
強調信号を出力する第１非線形処理部と、水平輪郭検出
部で検出した輪郭成分に非線形処理をして水平方向の輪
郭強調信号を出力する第２非線形処理部とで構成し、第
１非線形処理部の出力する輪郭強調信号と第２非線形処
理部の出力する輪郭強調信号を加算して加算手段へ出力
する輪郭強調加算器を設けたので、垂直方向及び水平方
向の輪郭強調を個別に制御することができる。このた
め、画像に適した輪郭強調を行うことができる。According to a sixth aspect of the present invention, in the first, second or third aspect, the contour detecting means comprises a vertical contour detecting section and a horizontal contour detecting section, and the non-linear processing means is detected by the vertical contour detecting section. A first nonlinear processing unit that performs nonlinear processing on a contour component and outputs a vertical contour emphasis signal, and a second nonlinear processing that performs nonlinear processing on a contour component detected by a horizontal contour detection unit and outputs a horizontal contour emphasis signal. A contour enhancement adder configured to add a contour enhancement signal output from the first nonlinear processing unit and a contour enhancement signal output from the second nonlinear processing unit and output the result to an adding unit. Directional and horizontal contour enhancement can be controlled individually. For this reason, contour enhancement suitable for an image can be performed.
【００３５】請求項７の発明は、請求項６の発明におい
て、輪郭強調加算器と加算手段の間に、輪郭強調加算器
から出力する輪郭強調信号を所定の上限レベル及び下限
レベルでクリップして加算手段へ出力するリミッタを設
けたので、加算手段で加算する輪郭強調信号の振幅を小
さくして回路構成を簡単にすることができる。According to a seventh aspect of the present invention, in the sixth aspect of the present invention, the edge enhancement signal output from the edge enhancement adder is clipped between the edge enhancement adder and the addition means at predetermined upper and lower levels. Since the limiter for outputting to the adding means is provided, the amplitude of the contour emphasizing signal to be added by the adding means can be reduced to simplify the circuit configuration.
【図１】本発明による輪郭強調回路の一実施形態例を示
すブロック図である。FIG. 1 is a block diagram showing an embodiment of an outline emphasis circuit according to the present invention.
【図２】図１の作用を説明する非線形な入出力特性図
で、（ａ）は設定値Ｓが５０の場合、（ｂ）は設定値Ｓ
が３０の場合の図である。FIGS. 2A and 2B are non-linear input / output characteristic diagrams for explaining the operation of FIG. 1, wherein FIG. 2A shows a case where a set value S is 50, and FIG.
FIG.
【図３】図１の非線形処理部をＬＵＴで置換した場合に
おける、ＬＵＴの非線形処理による入出力特性図であ
る。FIG. 3 is an input / output characteristic diagram obtained by performing non-linear processing on an LUT when the non-linear processing unit in FIG. 1 is replaced with an LUT.
【図４】本発明による輪郭強調回路の他の実施形態例を
示すブロック図である。FIG. 4 is a block diagram showing another embodiment of the contour emphasizing circuit according to the present invention.
【図５】本発明による輪郭強調回路のさらに他の実施形
態例を示すブロック図である。FIG. 5 is a block diagram showing still another embodiment of the contour emphasizing circuit according to the present invention.
【図６】従来例の輪郭強調回路を示すブロック図であ
る。FIG. 6 is a block diagram showing a conventional outline emphasis circuit.
【図７】図６の作用を説明する信号波形図である。FIG. 7 is a signal waveform diagram for explaining the operation of FIG. 6;
【図８】他の従来例の輪郭強調回路を示すブロック図で
ある。FIG. 8 is a block diagram showing another conventional outline emphasis circuit.
【図９】図８の作用を説明する入出力特性図である。FIG. 9 is an input / output characteristic diagram for explaining the operation of FIG. 8;
３０…水平輪郭検出部（輪郭検出手段の一例）、 ３１
…入力端子、 ３２、３２ｈ、３２ｖ…非線形処理部、
３４…遅延器、 ３６…加算部、 ３７…出力端子、
３８、４０、６２…１ドット遅延値、 ４２、４８、
７２、７８…加算器、 ４４、４６、７４、７６…乗算
器、 ５０…絶対値変換回路、 ５２…乗算器（掛ける
係数が１を越えている乗算器）、 ５４…比較器、 ５
６…セレクタ、 ５８…符号器、 ６０…垂直輪郭検出
部（輪郭検出手段の一例）、 ６４…輪郭成分加算器、
６６…リミッタ、 ６８、７０…１ライン遅延器、
８０…輪郭強調加算器、 ＨＥ…水平方向の輪郭成分、
ＨＥｅ…水平方向の輪郭強調信号、 Ｓ…設定値、
ＶＥ…垂直方向の輪郭成分、 ＶＥｅ…垂直方向の輪郭
強調信号、 Ｙ…入力輝度信号。30 ... horizontal contour detecting section (an example of contour detecting means), 31
... input terminals, 32, 32h, 32v ... nonlinear processing units
34 delay unit, 36 addition unit, 37 output terminal,
38, 40, 62... 1 dot delay value, 42, 48,
72, 78: adders, 44, 46, 74, 76: multipliers, 50: absolute value conversion circuit, 52: multipliers (multipliers whose coefficient to be multiplied exceeds 1), 54: comparators, 5
Reference numeral 6: selector, 58: encoder, 60: vertical contour detector (an example of a contour detector), 64: contour component adder,
66 ... limiter, 68, 70 ... one-line delay device,
80: contour emphasis adder, HE: horizontal contour component,
HEe: horizontal edge enhancement signal, S: set value,
VE: vertical edge component; VEe: vertical edge emphasis signal; Y: input luminance signal.
───────────────────────────────────────────────────── フロントページの続き (72)発明者 小野寺 純一 神奈川県川崎市高津区末長1116番地 株式 会社富士通ゼネラル内 ──────────────────────────────────────────────────続 き Continuing on the front page (72) Inventor Junichi Onodera 1116 Suenaga, Takatsu-ku, Kawasaki-shi, Kanagawa Prefecture Fujitsu General Co., Ltd.
Claims (7)
る輪郭検出手段と、この輪郭検出手段で検出した輪郭成
分をその振幅に応じて非線形に処理して輪郭強調信号を
出力する非線形処理手段と、この非線形処理手段から出
力する輪郭強調信号を前記入力輝度信号に加算して輪郭
強調された輝度信号を出力する加算手段とを具備し、前
記非線形処理手段による非線形特性を、前記輪郭成分の
振幅の絶対値が設定値よりも大きい信号については抑圧
特性とし、前記輪郭成分の振幅の絶対値が前記設定値よ
りも小さい信号については強調特性としてなる輪郭強調
回路。1. A contour detecting means for detecting a contour component from an input luminance signal, and a non-linear processing means for non-linearly processing the contour component detected by the contour detecting means in accordance with its amplitude and outputting a contour emphasis signal. And an adding means for adding a contour emphasizing signal output from the non-linear processing means to the input luminance signal and outputting a contour-emphasized luminance signal, and A contour emphasizing circuit in which a signal whose absolute value of the amplitude is larger than a set value has a suppression characteristic, and a signal whose absolute value of the amplitude of the contour component is smaller than the set value has an emphasis characteristic.
た輪郭成分を絶対値に変換して出力する絶対値変換回路
と、この絶対値変換回路の出力に１より大きな係数を掛
けて出力する乗算器と、前記絶対値変換回路の出力と設
定値とを比較する比較器と、この比較器の比較出力に基
づいて前記乗算器の出力と設定値の一方を選択して出力
するセレクタと、このセレクタの出力に前記輪郭成分の
正負に応じた符号をつけ輪郭強調信号として出力する符
号器とからなる請求項１記載の輪郭強調回路。2. An absolute value conversion circuit for converting a contour component detected by the contour detection means into an absolute value and outputting the converted value, and multiplying the output of the absolute value conversion circuit by a coefficient larger than 1 for output. A multiplier, a comparator that compares the output of the absolute value conversion circuit with a set value, and a selector that selects and outputs one of the output and the set value of the multiplier based on a comparison output of the comparator, 2. A contour emphasizing circuit according to claim 1, further comprising an encoder for attaching a sign to the output of said selector in accordance with the sign of said contour component and outputting the sign as a contour emphasizing signal.
た輪郭成分をアドレスの入力とし、輪郭強調信号をアド
レスの内容として出力するルックアップテーブルとして
なり、このルックアップテーブルの入出力特性を非線形
特性曲線で形成し、この非線形特性曲線を、前記輪郭成
分の振幅の絶対値が設定値よりも大きい信号については
接線の傾きが１より小さくなり、前記輪郭成分の振幅の
絶対値が前記設定値よりも小さい信号については接線の
傾きが１より大きくなる特性曲線としてなる請求項１記
載の輪郭強調回路。3. The non-linear processing means is a look-up table which receives the contour component detected by the contour detecting means as an input of an address and outputs a contour emphasis signal as the contents of the address. This nonlinear characteristic curve is formed by a characteristic curve. For a signal whose absolute value of the amplitude of the contour component is larger than a set value, the slope of the tangent becomes smaller than 1, and the absolute value of the amplitude of the contour component is set to the set value. 2. The contour emphasizing circuit according to claim 1, wherein a signal smaller than said signal is a characteristic curve in which a slope of a tangent is larger than 1.
出する垂直輪郭検出部と、水平方向の輪郭成分を検出す
る水平輪郭検出部とからなり、前記垂直輪郭検出部で検
出した輪郭成分と前記水平輪郭検出部で検出した輪郭成
分とを加算して非線形処理手段へ出力する輪郭成分加算
器を設けてなる請求項１、２又は３記載の輪郭強調回
路。4. The contour detecting means comprises a vertical contour detecting section for detecting a vertical contour component, and a horizontal contour detecting section for detecting a horizontal contour component, wherein the contour component detected by the vertical contour detecting section is provided. 4. The contour emphasizing circuit according to claim 1, further comprising a contour component adder for adding the contour component detected by the horizontal contour detecting section and outputting the result to the nonlinear processing means.
前記輪郭成分加算器から出力する輪郭成分を所定の上限
レベル及び下限レベルでクリップして前記非線形処理手
段へ出力するリミッタを設けてなる請求項４記載の輪郭
強調回路。5. A method according to claim 1, further comprising the step of:
5. The contour emphasizing circuit according to claim 4, further comprising a limiter for clipping a contour component output from said contour component adder at predetermined upper and lower levels and outputting the clipped component to said nonlinear processing means.
出する垂直輪郭検出部と、水平方向の輪郭成分を検出す
る水平輪郭検出部とからなり、非線形処理手段は、前記
垂直輪郭検出部で検出した輪郭成分に非線形処理をして
垂直方向の輪郭強調信号を出力する第１非線形処理部
と、前記水平輪郭検出部で検出した輪郭成分に非線形処
理をして水平方向の輪郭強調信号を出力する第２非線形
処理部とからなり、前記第１非線形処理部の出力する輪
郭強調信号と前記第２非線形処理部の出力する輪郭強調
信号を加算して加算手段へ出力する輪郭強調加算器を設
けてなる請求項１、２又は３記載の輪郭強調回路。6. The contour detecting means comprises a vertical contour detecting section for detecting a vertical contour component, and a horizontal contour detecting section for detecting a horizontal contour component, and the non-linear processing means comprises the vertical contour detecting section. A first nonlinear processing unit that performs nonlinear processing on the contour component detected in step 1 and outputs a vertical contour enhancement signal, and a nonlinear processing on the contour component detected by the horizontal contour detection unit to generate a horizontal contour enhancement signal. A contour enhancement signal output from the first nonlinear processor and a contour enhancement signal output from the second nonlinear processor, and output to an adding means. 4. The contour emphasizing circuit according to claim 1, wherein the contour emphasizing circuit is provided.
郭強調加算器から出力する輪郭強調信号を所定の上限レ
ベル及び下限レベルでクリップして前記加算手段へ出力
するリミッタを設けてなる請求項６記載の輪郭強調回
路。7. A limiter is provided between the contour emphasis adder and the addition means for clipping the contour emphasis signal output from the contour emphasis adder at predetermined upper and lower levels and outputting the clipped signal to the addition means. The contour emphasizing circuit according to claim 6.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP10059009A JPH11243496A (en) | 1998-02-24 | 1998-02-24 | Contour emphasizing circuit |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP10059009A JPH11243496A (en) | 1998-02-24 | 1998-02-24 | Contour emphasizing circuit |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| JPH11243496A true JPH11243496A (en) | 1999-09-07 |
Family
ID=13100874
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP10059009A Pending JPH11243496A (en) | 1998-02-24 | 1998-02-24 | Contour emphasizing circuit |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPH11243496A (en) |
Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2005309570A (en) * | 2004-04-19 | 2005-11-04 | Megachips Lsi Solutions Inc | Image signal emphasizing device |
| EP1613059A1 (en) * | 2004-06-30 | 2006-01-04 | Kabushiki Kaisha Toshiba | Apparatus and method for processing video signal |
| JP2007306505A (en) * | 2006-05-15 | 2007-11-22 | Ｎｅｃディスプレイソリューションズ株式会社 | Apparatus and method for improving picture quality |
-
1998
- 1998-02-24 JP JP10059009A patent/JPH11243496A/en active Pending
Cited By (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2005309570A (en) * | 2004-04-19 | 2005-11-04 | Megachips Lsi Solutions Inc | Image signal emphasizing device |
| EP1613059A1 (en) * | 2004-06-30 | 2006-01-04 | Kabushiki Kaisha Toshiba | Apparatus and method for processing video signal |
| US7391477B2 (en) | 2004-06-30 | 2008-06-24 | Kabushiki Kaisha Toshiba | Apparatus and method for processing video signal |
| JP2007306505A (en) * | 2006-05-15 | 2007-11-22 | Ｎｅｃディスプレイソリューションズ株式会社 | Apparatus and method for improving picture quality |
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