JP3662514B2

JP3662514B2 - Defective pixel detection and correction device, defective pixel detection and correction method, defective pixel detection and correction program, and video signal processing device

Info

Publication number: JP3662514B2
Application number: JP2001135020A
Authority: JP
Inventors: 功一星野; 憲治田部井; 信須部
Original assignee: Panasonic Corp; Matsushita Electric Industrial Co Ltd
Current assignee: Panasonic Corp; Panasonic Holdings Corp
Priority date: 2001-05-02
Filing date: 2001-05-02
Publication date: 2005-06-22
Anticipated expiration: 2021-05-02
Also published as: JP2002330354A

Description

【０００１】
【発明の属する技術分野】
本発明は、固体撮像素子の出力から、荷電粒子や２次宇宙線や高温状態等が原因で発生する欠損画素を検出して補正する欠損画素検出補正装置、欠損画素検出補正方法、欠損画素検出補正プログラム、および、固体撮像素子の出力に対して信号処理を行う映像信号処理装置に関するものである。
【０００２】
【従来の技術】
従来、固体撮像素子の出力から欠損画素を検出して補正する方法として、特開昭５６−４４２７４号公報に記載された方法がある。この従来の方法は、固体撮像素子の欠損画素の座標のアドレスをメモリに予め書き込んでおいて、映像信号の画素座標を示す水平アドレスカウンタと垂直アドレスカウンタとを監視し、これらのカウンタがメモリに書き込まれた座標のアドレスと一致したとき、補正回路を制御して欠損画素を直前の正常な画素と置き換えるようになっていた。
【０００３】
また、従来、メモリを使わずにリアルタイムに欠損画素を検出して補正する方法として、特開平４−３４５３８３号公報に記載された方法がある。この従来の方法は、隣接画素出力回路によって固体撮像素子の出力から上下左右の方向において隣接画素を取り出し、２つの閾値合成手段によって上下方向、左右方向それぞれの閾値を合成する。その閾値と補正対象画素の信号レベルとを比較して、補正対象画素の信号レベルが２つの閾値よりも大きいとき、補正対象画素を欠損画素と判定して直前の画素と置き換えるようになっていた。
【０００４】
【発明が解決しようとする課題】
しかしながら、前述した固体撮像素子の欠損画素の座標を予めメモリに書き込んでおく従来の方法では、工場出荷前に欠損画素の座標を予め調べてＲＯＭ等のメモリに書き込まなければならず、手間がかかるという問題があった。また、工場に設備が必要であるとともに部品点数が増加するという問題があった。
【０００５】
また、前述したリアルタイムに欠損画素を検出して直前の画素と置き換える従来の方法では、欠損画素の左右にまで欠損画素が広がった状態の連続欠損画素に対して補正をすることができないという問題があった。
【０００６】
本発明は、このような問題を解決するためになされたもので、欠損画素の座標を予め調べてメモリに書き込む必要がなく、リアルタイムに欠損画素を検出して補正することができる欠損画素検出補正装置、欠損画素検出補正方法、欠損画素検出補正プログラム、および、映像信号処理装置を提供するものである。
【０００７】
【課題を解決するための手段】
本発明の欠損画素検出補正装置は、同一の被写体を撮像した複数の固体撮像素子の出力から補正対象画素とこの補正対象画素の周辺に位置する複数の周辺画素とを有したエリアを生成する補正検出エリア生成手段と、前記複数の周辺画素について周辺最大値と周辺最小値とを検出する最大値・最小値検出手段と、前記周辺最大値と前記周辺最小値と前記補正対象画素の値とに基づいて、前記補正対象画素が欠損画素であるか否かを判定する欠損画素判定手段と、前記固体撮像素子毎に判定した複数の欠損画素判定結果の組み合わせにより前記補正対象画素が欠損画素であるか否かを判定する第２の欠損画素判定手段と、前記補正対象画素が欠損画素であると判定されたとき、前記補正対象画素の値を補正した値に切り替える切替手段とを備えた構成を有している。この構成により、欠損画素の座標を予め調べてメモリに書き込む必要がなく、また、リアルタイムに欠損画素を検出して補正することができ、出荷後に発生した欠損画素であっても検出して補正することができることとなる。
【０００８】
本発明の欠損画素検出補正装置は、前記最大値・最小値検出手段が、前記エリア内において前記補正対象画素に隣接した複数の周辺画素の最小値と、前記エリア内のその他複数の周辺画素の最大値とを比較し、より大きい値を前記周辺最大値とする構成を有している。この構成により、補正対象画素の隣の画素が信号レベルの高い欠損画素（白欠損画素）であっても、周辺最大値に欠損画素の値が選択されることを防ぐことができ、欠損画素を検出して補正することができることとなる。
【０００９】
本発明の欠損画素検出補正装置は、前記最大値・最小値検出手段が、前記エリア内において前記補正対象画素に隣接した複数の周辺画素の最大値と、前記エリア内のその他複数の周辺画素の最小値とを比較し、より小さい値を前記周辺最小値とする構成を有している。この構成により、補正対象画素の隣の画素が信号レベルの低い欠損画素（黒欠損画素）であっても、周辺最大値に欠損画素の値が選択されることを防ぐことができ、欠損画素を検出して補正することができることとなる。
【００１３】
本発明の欠損画素検出補正装置は、前記複数の欠損画素判定結果の２つ以上が前記補正対象画素は欠損画素であるとした判定であるとき、前記第２の欠損画素判定手段が、前記補正対象画素は欠損画素でないとする判定に置き換える構成を有している。この構成により、簡単な構成によって、画像の輪郭部分にある正常画素を欠損画素と誤検出してしまうことを防ぐことができることとなる。
【００１５】
本発明の欠損画素検出補正装置は、同一の被写体を撮像した複数の固体撮像素子の出力から補正対象画素とこの補正対象画素の周辺に位置する複数の周辺画素とを有したエリアを生成するステップと、一方の前記固体撮像素子の出力と他方の前記固体撮像素子の出力との比率を同一座標の画素毎に計算するとともに、前記複数の周辺画素の比率最大値と比率最小値とを求める比率計算手段と、前記補正対象画素の比率と前記比率最大値と前記比率最小値とを比較し、前記補正対象画素が欠損画素であるか否かを判定する比較手段と、前記補正対象画素が欠損画素であると判定されたとき、前記補正対象画素を補正する補正手段とを備えた構成を有している。この構成により、欠損画素の座標を予め調べてメモリに書き込む必要がなく、また、リアルタイムに欠損画素を検出して補正することができ、出荷後に発生した欠損画素であっても検出して補正することができることとなる。また、欠損画素の検出精度を向上することができることとなる。
【００１６】
本発明の欠損画素補正方法は、同一の被写体を撮像した複数の固体撮像素子の出力から補正対象画素とこの補正対象画素の周辺に位置する複数の周辺画素とを有したエリアを生成するステップと、前記エリア内において前記補正対象画素に隣接した複数の周辺画素の最大値と、前記エリア内のその他複数の周辺画素の最小値とを比較し、より小さい値を周辺最小値とするステップと、前記エリア内において前記補正対象画素に隣接した複数の周辺画素の最小値と、前記エリア内のその他複数の周辺画素の最大値とを比較し、より大きい値を周辺最大値とするステップと、前記周辺最大値と前記周辺最小値と前記補正対象画素の値とに基づいて、前記補正対象画素が欠損画素であるか否かを判定するステップと、前記固体撮像素子毎に判定した複数の欠損画素判定結果の組み合わせにより前記補正対象画素が欠損画素であるか否かを判定するステップと、前記補正対象画素が欠損画素であると判定されたとき、前記補正対象画素を補正するステップとを備えた構成を有している。この構成により、欠損画素の座標を予め調べてメモリに書き込む必要がなく、また、リアルタイムに欠損画素を検出して補正することができ、出荷後に発生した欠損画素であっても検出して補正することができることとなる。また、補正対象画素の隣の画素が信号レベルの高い欠損画素（白欠損画素）、または、信号レベルの低い欠損画素（黒欠損画素）であっても、周辺最大値に欠損画素の値が選択されることを防ぐことができ、欠損画素を検出して補正することができることとなる。
【００１８】
本発明の欠損画素検出補正プログラムは、同一の被写体を撮像した複数の固体撮像素子の出力から欠損画素を検出して補正する機能をコンピュータに実現させる欠損画素検出補正プログラムであって、前記同一の被写体を撮像した複数の固体撮像素子の出力から補正対象画素とこの補正対象画素の周辺に位置する複数の周辺画素とを有したエリアを生成する補正検出エリア生成手段と、前記エリア内において前記補正対象画素に隣接した複数の周辺画素の最大値と、前記エリア内のその他複数の周辺画素の最小値とを比較し、より小さい値を周辺最小値とするとともに、前記エリア内において前記補正対象画素に隣接した複数の周辺画素の最小値と、前記エリア内のその他複数の周辺画素の最大値とを比較し、より大きい値を周辺最大値とする最大値・最小値検出手段と、前記周辺最大値と前記周辺最小値と前記補正対象画素の値とに基づいて、前記補正対象画素が欠損画素であるか否かを判定する欠損画素判定手段と、前記固体撮像素子毎に判定した複数の欠損画素判定結果の組み合わせにより前記補正対象画素が欠損画素であるか否かを判定する第２の欠損画素判定手段と、前記補正対象画素が欠損画素であると判定されたとき、前記補正対象画素を補正する補正手段として、前記コンピュータを機能させる構成を有している。この構成により、欠損画素の座標を予め調べてメモリに書き込む必要がなく、また、リアルタイムに欠損画素を検出して補正することができ、出荷後に発生した欠損画素であっても検出して補正することができることとなる。また、補正対象画素の隣の画素が信号レベルの高い欠損画素（白欠損画素）、または、信号レベルの低い欠損画素（黒欠損画素）であっても、周辺最大値に欠損画素の値が選択されることを防ぐことができ、欠損画素を検出して補正することができることとなる。
【００２０】
本発明の映像信号処理装置は、画素の輪郭強調を行う輪郭強調手段を備えた映像信号処理装置であって、請求項１乃至請求項５のいずれかに記載の欠損画素検出補正装置から出力された欠損画素判定結果に基づいて、正常画素のみ前記輪郭強調手段によって輪郭強調を行い、欠損画素は輪郭強調を行わないように切り替える切替手段を設けた構成を有している。この構成により、正常画素と判定された画素だけに輪郭強調が施され、輪郭がはっきりした画像が得られることとなる。
【００２１】
【発明の実施の形態】
以下、本発明の実施の形態について、図面を用いて説明する。
【００２２】
（第１実施形態）
図１は本発明の第１実施形態における欠損画素検出補正装置を示す。図２はその欠損画素検出補正装置の補正検出エリア生成手段によって生成された補正検出エリアの例を示す。図３はその欠損画素検出補正装置の最大値・最小値検出手段の例を示す。
【００２３】
図１において、本実施形態の欠損画素検出補正装置は、固体撮像素子１に接続した補正検出エリア生成手段３と、最大値・最小値検出手段５と、欠損画素判定手段９と、切替手段１３とから構成されている。
【００２４】
補正検出エリア生成手段３は、固体撮像素子１が出力した撮像素子出力信号２から、図２に示すような、欠損画素であるか否かを調べる補正対象画素Ｉを中心とした、上のライン５画素（画素Ａ〜画素Ｅ）、センタライン７画素（画素Ｆ〜画素Ｌ）および下のライン５画素（画素Ｍ〜画素Ｑ）からなる補正検出エリアを順次選択し、この補正検出エリア内にある補正対象画素Ｉおよび周辺画素（画素Ａ〜画素Ｈ、画素Ｊ〜画素Ｑ）それぞれの値（信号レベル）を、補正検出エリア信号４として出力する。
【００２５】
最大値・最小値検出手段５は、図３に示すように、周辺最大値６を検出する周辺最大値検出ブロック５１と、周辺最小値７を検出する周辺最小値検出ブロック５２とから構成されている。周辺最大値検出ブロック５１は、補正検出エリア内において補正対象画素Ｉに隣接した周辺画素（画素Ｇ、画素Ｈ、画素Ｊ、画素Ｋ）の値（ＬＧ、ＬＨ、ＬＪ、ＬＫ）の中の最小値と、補正検出エリア内のその他の周辺画素（画素Ａ〜画素Ｆ、画素Ｌ〜画素Ｑ）の値（ＬＡ、ＬＢ、ＬＣ、ＬＤ、ＬＥ、ＬＦ、ＬＬ、ＬＭ、ＬＮ、ＬＯ、ＬＰ、ＬＱ）の中の最大値とを比較して、より大きい値を周辺最大値６とする。また、周辺最小値検出ブロック５２は、補正検出エリア内において補正対象画素に隣接した周辺画素（画素Ｇ、画素Ｈ、画素Ｊ、画素Ｋ）の値（ＬＧ、ＬＨ、ＬＪ、ＬＫ）の中の最大値と、補正検出エリア内のその他の周辺画素（画素Ａ〜画素Ｆ、画素Ｌ〜画素Ｑ）の値（ＬＡ、ＬＢ、ＬＣ、ＬＤ、ＬＥ、ＬＦ、ＬＬ、ＬＭ、ＬＮ、ＬＯ、ＬＰ、ＬＱ）の中の最小値とを比較して、より小さい値を周辺最小値７とする。
【００２６】
なお、周辺最大値６を検出する際、補正対象画素に隣接した周辺画素（画素Ｇ、画素Ｈ、画素Ｊ、画素Ｋ）の値の中から最小値を求める理由は、補正対象画素Ｉが白欠損画素であって、例えば画素Ｈおよび画素Ｊにも欠損が広がっている場合、画素Ｈの値ＬＨや画素Ｊの値ＬＪが大きくなっており、この値ＬＨまたは値ＬＪを周辺最大値としてしまうと、補正対象画素が欠損画素であるか否かを判定する際に欠損画素の検出精度が落ちてしまうからである。本実施形態においては、仮に画素Ｈまたは画素Ｊが白欠損画素であっても画素Ｇ、画素Ｈ、画素Ｊ、画素Ｋの値の中から最小値を選択するようになっているので、画素Ｇの値または画素Ｋの値が選択され、欠損画素の検出精度を上げることができることとなる。また、周辺最小値７を検出する際、補正対象画素に隣接した周辺画素（画素Ｇ、画素Ｈ、画素Ｊ、画素Ｋ）の値の中から最大値を求める理由は、補正対象画素Ｉが黒欠損画素であって、例えば画素Ｈや画素Ｊにも欠損が広がっている場合、画素Ｈの値ＬＨや画素Ｊの値ＬＪが小さくなっており、この値ＬＨまたは値ＬＪを周辺最小値としてしまうと、補正対象画素が欠損画素であるか否かを判定する際に欠損画素の検出精度が落ちてしまうからである。本実施形態においては、仮に画素Ｈまたは画素Ｊが黒欠損画素であっても、画素Ｇ、画素Ｈ、画素Ｊ、画素Ｋの値の中から最大値を選択するようになっているので、画素Ｇの値または画素Ｋの値が選択され、欠損画素の検出精度を上げることができることとなる。
【００２７】
欠損画素判定手段９は、周辺最大値６と周辺最小値７と補正対象画素値８とに基づいて、補正対象画素が欠損画素であるか否かを判定する。まず、補正対象画素値８と周辺最大値６との差分値（補正対象画素値８−周辺最大値６）を計算し、この差分値と外部から設定された閾値１０とを比較する。比較した結果、差分値が閾値１０より大きいとき、補正対象画素値８が補正検出エリア内の周辺画素の値と比べて突出して大きいことになり、補正対象画素Ｉは白欠損画素であると判定する。また、差分値が閾値１０より小さいとき、次に、周辺最小値７と補正対象画素値８との差分値（周辺最小値７−補正対象画素値８）を計算し、この差分値と外部から設定された閾値１０とを比較する。比較した結果、差分値が閾値１０より大きいとき、補正対象画素値８が補正検出エリア内のその他の周辺画素の値と比べて突出して小さいことになり、補正対象画素Ｉは黒欠損画素であると判定する。
【００２８】
欠損画素判定手段９は、補正対象画素が白欠損画素または黒欠損画素であると判定した場合、欠損画素判定信号１２を出力する。また、欠損画素判定手段９は、補正対象画素が白欠損画素であると判定したとき、周辺最大値６を補正値１１として出力し、補正対象画素が黒欠損画素であると判定したとき、周辺最小値７を補正値１１として出力する。
【００２９】
切替手段１３は、欠損画素判定信号１２に応じて、補正対象画素Ｉが白欠損画素であるとき、補正対象画素値８を周辺最大値６に切り替えて欠損画素補正出力信号１４として出力し、補正対象画素Ｉが黒欠損画素であるとき、補正対象画素値８を周辺最小値７に切り替えて欠損画素補正出力信号１４として出力し、補正対象画素Ｉが欠損画素でないとき、補正対象画素値８を欠損画素補正出力信号１４として出力する。
【００３０】
前述した構成により、本実施形態の欠損画素検出補正装置は、欠損画素の座標を予め調べてメモリに書き込む必要がなく、また、リアルタイムに欠損画素を検出して補正することができ、出荷後に発生してしまった欠損画素であっても検出して補正することができることとなる。
【００３１】
また、本実施形態の欠損画素検出補正装置は、補正対象画素の隣の画素が信号レベルの高い欠損画素（白欠損画素）であっても、周辺最大値に欠損画素の値が選択されることを防ぐことができ、また、補正対象画素の隣の画素が信号レベルの低い欠損画素（黒欠損画素）であっても、周辺最小値に欠損画素の値が選択されることを防ぐことができ、欠損画素を検出して補正することができることとなる。
【００３２】
（第２実施形態）
図４は本発明の第２実施形態における欠損画素検出補正装置を示す。なお、図１に示す第１実施形態の構成要件と同じ構成要件は、同じ符号としてある。
【００３３】
図４において、本実施形態の欠損画素検出補正装置は、第１実施形態の欠損画素検出補正装置に対して、周辺最大値と周辺最小値との差分値に応じて複数の閾値候補の中から選択した閾値を出力する閾値切替手段４１を追加したものである。
【００３４】
閾値切替手段４１は、周辺最大値６と周辺最小値７との差分値を計算し、閾値切替手段４１に複数入力された閾値候補（閾値第１候補、閾値第２候補、…、閾値第Ｎ候補）から差分値に応じた閾値を選択して、欠損画素判定手段９に出力するようになっている。具体的には、周辺最大値６と周辺最小値７との差分値が大きいとき、差分値に応じた大きな値の閾値候補を選択し、また周辺最大値６と周辺最小値７との差分値が小さいとき、差分値に応じた小さな値の閾値候補を選択する。
【００３５】
したがって、本実施形態の欠損画素検出補正装置は、補正検出エリア内の画素値のばらつきが大きいとき、間違って正常画素を欠損画素と判定しないようにすることができ、また、補正検出エリア内の画素値のばらつきが小さいとき、欠損画素を見逃さないで検出するようにすることができ、欠損画素の検出精度を向上することができることとなる。
【００３６】
（第３実施形態）
図５は本発明の第２実施形態における欠損画素検出補正装置を示す。なお、図１に示す第１実施形態の構成要件と同じ構成要件は、同じ符号としてある。
【００３７】
図５において、本実施形態の欠損画素検出補正装置は、第１実施形態の欠損画素検出補正装置に対して、周辺画素の平均値を計算する画素平均計算手段５１と、周辺画素の平均値に応じて複数の閾値候補の中から選択した閾値を出力する閾値切替手段５２とを追加したものである。
【００３８】
明るい画像では白欠損画素の検出が難しく黒欠損画素の検出は容易で、逆に暗い画像では白欠損画素の検出は容易で黒欠損画素の検出は難しい。また、同一の画像でも明るい画像のところと暗い画像のところがある。しかしながら、本実施形態の欠損画素検出補正装置は、それぞれの補正検出エリアにおいて、画素平均計算手段５１が、周辺画素の値の平均値を計算し、閾値切替手段５２が、閾値切替手段５２に複数入力された閾値候補（閾値第１候補、閾値第２候補、…、閾値第Ｎ候補）から平均値に応じた閾値を選択して、欠損画素判定手段９に出力するようになっている。具体的には、明るい部分、すなわち平均値の大きいところは平均値に応じて小さな値の閾値候補を選択し、暗い部分、すなわち平均値の小さいところは平均値に応じた大きな値の閾値候補を選択する。
【００３９】
したがって、本実施形態の欠損画素検出補正装置は、欠損画素の検出精度を向上することができることとなる。
【００４０】
（第４実施形態）
図６は本発明の第４実施形態における欠損画素検出補正装置を示す。なお、図１に示す第１実施形態の構成要件と同じ構成要件は、同じ符号としてある。
【００４１】
図６において、本実施形態の欠損画素検出補正装置は、同一の被写体を撮像した複数の固体撮像素子１からの撮像素子出力信号２によって欠損画素判定を行うようになっている。また、本実施形態の欠損画素検出補正装置は、補正検出エリア生成手段３と、最大値・最小値検出手段５と、欠損画素判定手段９と、切替手段１３とをそれぞれ２つ備える。また、本実施形態の欠損画素検出補正装置は、固体撮像素子１毎に補正対象画素が欠損画素であるか否かを判定した複数の欠陥画素判定信号１２の組み合わせによって、補正対象画素が欠損画素であるか否かを最終的に判定する欠損画素相互判定手段６１（第２の欠損画素判定手段）を備える。
【００４２】
欠損画素相互判定手段６１は、欠損画素判定信号１２を同じ座標の補正対象画素ごとに比較して、２つ以上の欠損画素判定信号１２が共に欠損画素であるとした判定であるとき、座標に対してランダムに発生する欠損画素が同じ座標にあることは確率的に非常に低いため、補正対象画素は欠損画素でないとする判定に置き換えて、欠損画素判定信号１２を切替手段１３に対して出力しないようになっている。
【００４３】
したがって、本実施形態の欠陥画素補正装置は、画像の輪郭部分にある正常画素を欠損画素と誤検出してしまうことを防ぐことができることとなる。
【００４４】
（第５実施形態（参考例））
図７は本発明の第５実施形態における欠損画素検出補正装置を示す。図８はその欠損画素検出補正装置の比率平均計算手段および比較手段の動作を説明するための図である。
【００４５】
図７において、本実施形態の欠損画素検出補正装置は、固体撮像素子１に接続した補正検出エリア生成手段３と、比率平均計算手段７１と、比較手段７３と、補正手段７４とから構成されている。
【００４６】
本実施形態は、同一の被写体を複数の固体撮像素子１で撮像して得られた撮像素子出力信号２によって欠損画素判定を行う。まず、一方の固体撮像素子１の撮像素子出力信号２について、補正検出エリア生成手段３によって、図８の（ａ）に示すような補正検出エリアを生成し、この補正検出エリア内の画素（画素Ａ１〜画素Ｑ１）の値（ＬＡ１〜ＬＱ１）を補正検出エリア信号４として出力する。他方の固体撮像素子の撮像素子出力信号についても、図８の（ｂ）に示すように、同一座標の補正検出エリアを生成し、この補正検出エリア内の画素（画素Ａ２〜画素Ｑ２）の値（ＬＡ２〜ＬＱ２）を補正検出エリア信号７２として出力する。次に、比率平均計算手段７１によって、図８の（ｃ）に示すように、一方の固体撮像素子の撮像素子出力信号２についての補正検出エリア信号４と他方の固体撮像素子の撮像素子出力信号についての補正検出エリア信号７２とにおいて、同一座標の画素毎に比率を計算し、その平均ＡＶＥ（比率平均）を求める。次に、比較手段７３によって、補正対象画素Ｉの比率、および、補正対象画素Ｉの左右に隣接する画素Ｈおよび画素Ｊそれぞれの比率が、比率平均ＡＶＥに比べて極端に大きいかどうか比較し、画素Ｈ、画素Ｉ、画素Ｊのなかで比率平均ＡＶＥに比べて極端に比率が大きい画素があったとき、その画素は欠損画素であると判定する。ここで、画素Ｈおよび画素Ｊについても比較を行うのは、連続欠損を調べるためである。次に、補正手段７４によって、欠損画素と判定された画素のみ、比率平均ＡＶＥと他方の固体撮像素子における同一座標の画素の値との積に値を置き換えることによって、欠損画素を補正する。
【００４７】
したがって、本実施形態の欠陥画素補正装置は、欠損画素の検出精度を向上することができることとなる。
【００４８】
（第６実施形態）
図９は本発明の第６実施形態における欠損画素検出補正装置を示す。
【００４９】
図９において、本実施形態の欠損画素検出補正装置は、固体撮像素子１に接続した補正検出エリア生成手段３と、比率計算手段９１と、比較手段９３と、補正手段９４とから構成されている。
【００５０】
本実施形態は、同一の被写体を複数の固体撮像素子１で撮像して得られた撮像素子出力信号２によって欠損画素判定を行う。まず、一方の固体撮像素子１の撮像素子出力信号２について、補正検出エリア生成手段３によって、補正対象画素とこの補正対象画素の周辺に位置する複数の周辺画素とを有した補正検出エリアを生成し、この補正検出エリア内の画素の値を補正検出エリア信号４として出力する。次に、比率計算手段９１によって、他の固定撮像素子の補正検出エリア信号９２も用いて、一方の前記固体撮像素子の出力と他方の前記固体撮像素子の出力との比率を同一座標の画素毎に計算し、補正対象画素比率９６、周辺画素の比率最大値９７、周辺画素の比率最小値９８を求める。次に、比較手段９３によって、補正対象画素画素比率９６が周辺画素の比率最大値９７と周辺画素の比率最小値９８との範囲内に入っているか否かを判定し、補正対象画素比率９６が範囲外の値であったとき、補正対象画素は欠損画素と判定し、判定結果９９を出力する。次に、補正手段９４によって、欠損画素と判定された補正対象画素の値を、比率最大値９７と比率最小値９８との平均値に置き換える。
【００５１】
したがって、本実施形態の欠陥画素補正装置は、画像の輪郭部分にある正常画素を欠損画素と誤検出してしまうことを防ぐことができることとなる。
【００５２】
（第７実施形態）
図１０は本発明の第７実施形態における欠損画素補正方法を示す。以下、図１０を用いて本発明の第７実施形態における欠損画素補正方法を説明する。
【００５３】
なお、本実施形態の欠損画素補正方法は、固体撮像素子の出力において補正対象画素とこの補正対象画素の周辺に位置する複数の周辺画素とを有したエリアを選択する補正検出エリア生成手段と、周辺画素について最大値および最小値を検出する最大値・最小値検出手段と、値の比較を行う比較手段と、補正対象画素の値を補正する補正手段とを備えた装置を用いて行う。
【００５４】
まず、補正検出エリア生成手段によって、図２に示すような、補正対象画素Ｉとこの補正対象画素Ｉの周辺に位置する複数の周辺画素とを有した補正検出エリアを生成する（Ｓ１１）。次に、最大値・最小値検出手段によって、図１０のＳ１２のステップに示した式を用いて、補正検出エリア内の周辺最大値と周辺最小値とを求める（Ｓ１２）。なお、図１０のＳ１２のステップに示したＬＡ、ＬＢ、ＬＣ、ＬＤ、ＬＥ、ＬＦ、ＬＧ、ＬＨ、ＬＪ、ＬＫ、ＬＬ、ＬＭ、ＬＮ、ＬＯ、ＬＰ、ＬＱは、図２に示す補正検出エリアの周辺画素Ａ、Ｂ、Ｃ、Ｄ、Ｅ、Ｆ、Ｇ、Ｈ、Ｊ、Ｋ、Ｌ、Ｍ、Ｎ、Ｏ、Ｐ、Ｑそれぞれの値（信号レベル）を示す。また、補正対象画素Ｉは値がＬＩである。次に、比較手段によって、白欠損画素検出を行う（Ｓ１３）。具体的には、補正対象画素の値と周辺最大値との差分を取り、あらかじめ設定されている閾値と比較する。Ｓ１３のステップにおいて、差分が閾値よりも小さい値でなかったとき、補正対象画素は補正検出エリアの中で突出して大きい値であり、すなわち補正対象画素は白欠損画素であると判定する。次に、比較手段によって、黒欠損画素検出を行う（Ｓ１４）。具体的には、補正対象画素の値と周辺最小値との差分を取り、あらかじめ設定されている閾値と比較する。Ｓ１４のステップにおいて、差分が閾値よりも小さい値でなかったとき、補正対象画素は補正検出エリアの中で突出して小さい値であり、すなわち補正対象画素は黒欠損画素であると判定する。補正対象画素が白欠損画素であると判定したとき、補正手段によって、補正対象画素の値を周辺最大値に置き換えることにより、白欠損画素を補正する（Ｓ１６）。また、補正対象画素が黒欠損画素であると判定したとき、補正手段によって、補正対象画素の値を周辺最小値に置き換えることにより、黒欠損画素を補正する。
【００５５】
なお、前述した図１０に示す欠損画素補正方法は、コンピュータを前記補正検出エリア生成手段と、前記最大値・最小値検出手段と、前記比較手段と、前記補正手段として機能させるプログラムによって実現するようにしてもよい。
【００５６】
（第８実施形態）
図１１は本発明の第８実施形態における欠損画素補正方法を示す。以下、図１１を用いて本発明の第８実施形態における欠損画素補正方法を説明する。
【００５７】
なお、本実施形態の欠損画素補正方法は、固体撮像素子の出力において補正対象画素とこの補正対象画素の周辺に位置する複数の周辺画素とを有したエリアを選択する補正検出エリア生成手段と、比率および比率の平均を計算する平均計算手段と、値の比較を行う比較手段と、補正対象画素の値を補正する補正手段とを備えた装置を用いて行う。
【００５８】
本実施形態は、同一の被写体を複数の固体撮像素子を用いて撮像して得られた撮像素子出力信号よって欠損画素判定を行う。まず、一方の固体撮像素子の撮像素子出力信号について、補正検出エリア生成手段によって、図２に示すような、補正対象画素Ｉとこの補正対象画素Ｉの周辺に位置する複数の周辺画素とを有した補正検出エリアを生成する（Ｓ２１）。他方の固体撮像素子の撮像素子出力信号についても、同様に、同一座標の補正検出エリアを生成する。次に、比率平均計算手段によって、図８に示すように、一方の固体撮像素子の撮像素子出力信号についての補正検出エリアと他方の固体撮像素子の撮像素子出力信号についての補正検出エリアとにおいて、同一座標の画素毎に値の比率を計算し、その平均ＡＶＥ（比率平均）を求める（Ｓ２２）。なお、図１１に示したＬＡ１〜ＬＱ１、ＬＡ２〜ＬＱ２は、図８の（ａ）に示す一方の固体撮像素子で撮像した画像における補正検出エリア内の画素Ａ１〜Ｑ１または図８の（ｂ）に示す他方の固体撮像素子で撮像した画像における補正検出エリア内の画素Ａ２〜Ｑ２それぞれの値を示す。次に、比較手段によって、補正対象画素の比率ＬＩ１／ＬＩ２、および、補正対象画素の左右に隣接する画素のそれぞれの比率ＬＨ１／ＬＨ２、ＬＪ１／ＬＪ２が、Ｓ２２のステップで求めた比率平均ＡＶＥと比べて極端に大きいかどうか比較し、比率平均ＡＶＥに比べて極端に比率が大きい画素があったとき、その画素は欠損画素であると判定する（Ｓ２３）。ここで、補正対象画素の左右に隣接する画素についても比較を行うのは、連続欠損を調べるためである。次に、補正手段によって、欠損画素と判定された画素のみ比率平均ＡＶＥと他方の固体撮像素子における同一座標の画素の値との積に値を置き換えることによって、欠損画素を補正する（Ｓ２４）。
【００５９】
なお、前述した図１１に示す欠損画素補正方法は、コンピュータを前記補正検出エリア生成手段と、前記比率平均計算手段と、前記比較手段と、前記補正手段として機能させるプログラムによって実現するようにしてもよい。
【００６０】
（第９実施形態）
図１２は本発明の一実施形態の映像信号処理装置を示す。
【００６１】
本実施形態の映像信号処理装置は、固体撮像素子１と、欠損画素検出補正装置１２１と、輪郭強調装置１２２とから構成されている。また、輪郭強調装置１２２は、輪郭強調画素選択手段１２３と輪郭強調手段１２４と切替手段１２５とを有している。
【００６２】
図１２において、欠損画素検出補正装置１２１は、前述した第１実施形態〜第８実施形態のいずれかにおいて説明した欠損画素検出補正装置である。この欠損画素検出補正装置１２１は、補正対象画素が欠損画素であると判定したとき、補正対象画素が欠損画素であることを示す欠損画素判定信号１２を、輪郭強調装置１２２の輪郭強調画素選択手段１２３に対して出力するとともに、補正対象画素の値を補正した欠損画素補正出力信号１４を、輪郭強調装置１２２の輪郭強調手段１２３に対して出力する。
【００６３】
輪郭強調装置１２２の輪郭強調画素選択手段１２３は、欠損画素補正出力信号１４との遅延量の調整などを行った切替信号１２６を、輪郭強調装置１２２の輪郭強調装置１２２の切替手段１２５に対して出力する。輪郭強調装置１２２の輪郭強調手段１２４は、欠損画素補正出力信号１４に対して輪郭強調を行う。輪郭強調装置１２２の切替手段１２５は、切替信号１２６に基づいて、輪郭強調されていない欠損画素補正出力信号１４、または、輪郭強調装置１２２の輪郭強調手段１２４よって輪郭強調された欠損画素補正出力信号１４を輪郭強調画素出力信号１２７として出力する。切替手段１２５は、具体的には、欠損画素検出補正装置１２１によって補正対象画素が欠損画素でないと判定されたとき、輪郭強調手段１２４よって輪郭強調された欠損画素補正出力信号１４を出力し、欠損画素検出補正装置１２１によって補正対象画素が欠損画素であると判定されたとき、輪郭強調手段１２４よって輪郭強調された欠損画素補正出力信号１４は出力せず、欠損画素検出補正装置１２１からの欠損画素補正出力信号１４をそのまま出力する。
【００６４】
したがって、本実施形態の映像信号処理装置は、正常画素と判定された画素だけに輪郭強調が施され、輪郭がはっきりした画像が得られることとなる。
【００６５】
【発明の効果】
本発明は、欠損画素の座標を予め調べてメモリに書き込む必要がなく、リアルタイムに欠損画素を検出して補正することができるという優れた効果を有する欠損画素検出補正装置、欠損画素検出補正方法、欠損画素検出補正プログラム、および、映像信号処理装置を提供することができるものである。
【図面の簡単な説明】
【図１】本発明の第１実施形態の欠損画素検出補正装置を示すブロック図
【図２】補正検出エリアの例を示す図
【図３】欠損画素検出補正装置の最大値・最小値検出手段の例を示す図
【図４】本発明の第２実施形態の欠損画素検出補正装置を示すブロック図
【図５】本発明の第３実施形態の欠損画素検出補正装置を示すブロック図
【図６】本発明の第４実施形態の欠損画素検出補正装置を示すブロック図
【図７】本発明の第５実施形態の欠損画素検出補正装置を示すブロック図
【図８】本発明の第５実施形態の欠損画素検出補正装置の比率平均計算手段および比較手段の動作を説明するための図
【図９】本発明の第６実施形態の欠損画素検出補正装置を示すブロック図
【図１０】本発明の第７実施形態の欠損画素検出補正方法を示すブロック図
【図１１】本発明の第８実施形態の欠損画素検出補正方法を示すブロック図
【図１２】本発明の一実施形態の映像信号処理装置を示すブロック図
【符号の説明】
１固体撮像素子
３補正検出エリア生成手段
５最大値・最小値検出手段
９欠損画素判定手段
１３切替手段
４１、５２閾値切替手段
５１画素平均計算手段
６１欠損画素相互判定手段（第２の欠損画素判定手段）
７１比率平均計算手段
７３、９３比較手段
７４、９４補正手段
９１比率計算手段
１２１欠損画素検出補正装置
１２２輪郭強調装置
１２３輪郭強調装置の輪郭強調画素選択手段
１２４輪郭強調装置の輪郭強調手段
１２５輪郭強調装置の切替手段[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a defective pixel detection correction device, a defective pixel detection correction method, and a defective pixel detection that detects and corrects a defective pixel caused by charged particles, secondary cosmic rays, a high temperature state, or the like from the output of a solid-state imaging device. The present invention relates to a correction program and a video signal processing apparatus that performs signal processing on the output of a solid-state imaging device.
[0002]
[Prior art]
Conventionally, as a method for detecting and correcting a defective pixel from the output of a solid-state imaging device, there is a method described in Japanese Patent Laid-Open No. 56-44274. In this conventional method, the address of the coordinates of the defective pixel of the solid-state imaging device is written in the memory in advance, and the horizontal address counter and the vertical address counter indicating the pixel coordinates of the video signal are monitored, and these counters are stored in the memory. When the address of the written coordinate coincides, the correction circuit is controlled to replace the defective pixel with the previous normal pixel.
[0003]
Conventionally, as a method for detecting and correcting a defective pixel in real time without using a memory, there is a method described in JP-A-4-345383. In this conventional method, adjacent pixels are extracted in the vertical and horizontal directions from the output of the solid-state imaging device by the adjacent pixel output circuit, and the threshold values in the vertical and horizontal directions are synthesized by two threshold value synthesis means. When the threshold and the signal level of the correction target pixel are compared, and the signal level of the correction target pixel is greater than the two thresholds, the correction target pixel is determined to be a defective pixel and replaced with the previous pixel. .
[0004]
[Problems to be solved by the invention]
However, in the conventional method in which the coordinates of the defective pixels of the solid-state imaging device described above are previously written in the memory, the coordinates of the defective pixels must be checked in advance and written in a memory such as a ROM before shipment from the factory, which is troublesome. There was a problem. In addition, there is a problem that the factory requires equipment and the number of parts increases.
[0005]
In addition, the above-described conventional method of detecting a defective pixel in real time and replacing the previous pixel cannot correct a continuous defective pixel in which the defective pixel extends to the left and right of the defective pixel. there were.
[0006]
The present invention has been made to solve such a problem, and it is not necessary to check the coordinates of the defective pixel in advance and write it to the memory, and can detect and correct the defective pixel in real time. An apparatus, a defective pixel detection correction method, a defective pixel detection correction program, and a video signal processing apparatus are provided.
[0007]
[Means for Solving the Problems]
The missing pixel detection correction apparatus of the present invention is Multiple images of the same subject Correction detection area generating means for generating an area having a correction target pixel and a plurality of peripheral pixels located around the correction target pixel from an output of the solid-state imaging device; and a peripheral maximum value and a peripheral minimum for the plurality of peripheral pixels Based on the maximum value / minimum value detecting means for detecting the value, the peripheral maximum value, the peripheral minimum value, and the value of the correction target pixel, it is determined whether or not the correction target pixel is a defective pixel. A missing pixel determination means; Second defective pixel determination means for determining whether or not the correction target pixel is a defective pixel by a combination of a plurality of defective pixel determination results determined for each solid-state imaging device; And switching means for switching the value of the correction target pixel to a corrected value when it is determined that the correction target pixel is a defective pixel. With this configuration, it is not necessary to check the coordinates of the defective pixel in advance and write it into the memory. In addition, it is possible to detect and correct the defective pixel in real time, and to detect and correct even the defective pixel generated after shipment. Will be able to.
[0008]
In the defective pixel detection and correction apparatus according to the present invention, the maximum value / minimum value detection means includes a minimum value of a plurality of peripheral pixels adjacent to the correction target pixel in the area and a plurality of other peripheral pixels in the area. A maximum value is compared, and a larger value is set as the peripheral maximum value. With this configuration, even if the pixel adjacent to the correction target pixel is a defective pixel (white defective pixel) with a high signal level, the value of the defective pixel can be prevented from being selected as the peripheral maximum value. It can be detected and corrected.
[0009]
In the defective pixel detection and correction apparatus according to the present invention, the maximum value / minimum value detection means includes a maximum value of a plurality of peripheral pixels adjacent to the correction target pixel in the area and a plurality of other peripheral pixels in the area. The minimum value is compared, and a smaller value is set as the peripheral minimum value. With this configuration, even if the pixel adjacent to the correction target pixel is a defective pixel (black defective pixel) with a low signal level, the value of the defective pixel can be prevented from being selected as the peripheral maximum value. It can be detected and corrected.
[0013]
In the defective pixel detection and correction apparatus of the present invention, when two or more of the plurality of defective pixel determination results are determinations that the correction target pixel is a defective pixel, the second defective pixel determination unit includes the correction The target pixel has a configuration replaced with a determination that it is not a defective pixel. With this configuration, it is possible to prevent a normal pixel in the contour portion of the image from being erroneously detected as a defective pixel with a simple configuration.
[0015]
The defective pixel detection and correction apparatus of the present invention generates an area having a correction target pixel and a plurality of peripheral pixels located around the correction target pixel from outputs of a plurality of solid-state imaging devices that have captured the same subject. And one of the above Solid A ratio calculating means for calculating the ratio of the output of the body imaging element and the output of the other solid-state imaging element for each pixel of the same coordinate, and for determining the ratio maximum value and the ratio minimum value of the plurality of peripheral pixels; Comparing means for comparing the ratio of the correction target pixel, the maximum ratio value, and the minimum ratio value to determine whether the correction target pixel is a defective pixel; and determining that the correction target pixel is a defective pixel And a correction means for correcting the correction target pixel. With this configuration, it is not necessary to check the coordinates of the defective pixel in advance and write it into the memory. In addition, it is possible to detect and correct the defective pixel in real time, and to detect and correct even the defective pixel generated after shipment. Will be able to. In addition, the detection accuracy of the defective pixel can be improved.
[0016]
The defective pixel correction method of the present invention is Multiple images of the same subject Generating an area having a correction target pixel and a plurality of peripheral pixels located around the correction target pixel from an output of the solid-state imaging device; and a plurality of peripheral pixels adjacent to the correction target pixel in the area Comparing the maximum value with the minimum values of a plurality of other peripheral pixels in the area and setting a smaller value as the peripheral minimum value; and a minimum of a plurality of peripheral pixels adjacent to the correction target pixel in the area Comparing the value with the maximum value of a plurality of other peripheral pixels in the area and setting a larger value as the peripheral maximum value; and the peripheral maximum value, the peripheral minimum value, and the value of the correction target pixel On the basis of determining whether the correction target pixel is a defective pixel; and Determining whether the correction target pixel is a defective pixel by a combination of a plurality of defective pixel determination results determined for each of the solid-state imaging devices; And a step of correcting the correction target pixel when it is determined that the correction target pixel is a defective pixel. With this configuration, it is not necessary to check the coordinates of the defective pixel in advance and write it into the memory. In addition, it is possible to detect and correct the defective pixel in real time, and to detect and correct even the defective pixel generated after shipment. Will be able to. Also, even if the pixel next to the correction target pixel is a defective pixel with a high signal level (white defective pixel) or a defective pixel with a low signal level (black defective pixel), the value of the defective pixel is selected as the peripheral maximum value. It is possible to prevent this, and it is possible to detect and correct a defective pixel.
[0018]
The missing pixel detection correction program of the present invention is Multiple images of the same subject A defective pixel detection correction program for causing a computer to realize a function of detecting and correcting a defective pixel from an output of a solid-state imaging device, Multiple images of the same subject Correction detection area generating means for generating an area having a correction target pixel and a plurality of peripheral pixels located around the correction target pixel from an output of the solid-state imaging device; and a plurality of adjacent detection target pixels in the area A maximum value of the peripheral pixels of the pixel and a minimum value of the other peripheral pixels in the area, and a smaller value is set as the minimum peripheral value, and a plurality of peripherals adjacent to the correction target pixel in the area A maximum value / minimum value detecting means for comparing a minimum value of a pixel with a maximum value of a plurality of other peripheral pixels in the area and setting a larger value as a peripheral maximum value; and the peripheral maximum value and the peripheral minimum value And a defective pixel determination means for determining whether the correction target pixel is a defective pixel based on the correction target pixel value; Second defective pixel determination means for determining whether or not the correction target pixel is a defective pixel by a combination of a plurality of defective pixel determination results determined for each solid-state imaging device; When it is determined that the correction target pixel is a defective pixel, the computer is configured to function as correction means for correcting the correction target pixel. With this configuration, it is not necessary to check the coordinates of the defective pixel in advance and write it into the memory. In addition, it is possible to detect and correct the defective pixel in real time, and to detect and correct even the defective pixel generated after shipment. Will be able to. Also, even if the pixel next to the correction target pixel is a defective pixel with a high signal level (white defective pixel) or a defective pixel with a low signal level (black defective pixel), the value of the defective pixel is selected as the peripheral maximum value. It is possible to prevent this, and it is possible to detect and correct a defective pixel.
[0020]
The video signal processing apparatus of the present invention is a video signal processing apparatus provided with a contour emphasizing means for emphasizing the contour of a pixel. 5 On the basis of the defective pixel detection result output from the defective pixel detection and correction apparatus according to any one of the above, a switching unit that performs contour enhancement by the contour emphasis unit only for normal pixels and switches so that the defective pixel does not perform contour emphasis It has the provided structure. With this configuration, only the pixels determined to be normal pixels are subjected to contour enhancement, and an image with a clear contour is obtained.
[0021]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, embodiments of the present invention will be described with reference to the drawings.
[0022]
(First embodiment)
FIG. 1 shows a defective pixel detection and correction apparatus according to a first embodiment of the present invention. FIG. 2 shows an example of the correction detection area generated by the correction detection area generation means of the defective pixel detection correction device. FIG. 3 shows an example of the maximum value / minimum value detection means of the defective pixel detection correction apparatus.
[0023]
In FIG. 1, the defective pixel detection and correction apparatus according to the present embodiment includes a correction detection area generation unit 3 connected to the solid-state imaging device 1, a maximum / minimum value detection unit 5, a defective pixel determination unit 9, and a switching unit 13. It consists of and.
[0024]
The correction detection area generating means 3 is an upper line centering on the correction target pixel I for checking whether or not it is a defective pixel, as shown in FIG. 2, from the image sensor output signal 2 output by the solid-state image sensor 1. A correction detection area consisting of 5 pixels (pixel A to pixel E), 7 center line pixels (pixel F to pixel L), and 5 line pixels below (pixel M to pixel Q) is sequentially selected, and this correction detection area is included. Values (signal levels) of a certain correction target pixel I and peripheral pixels (pixel A to pixel H, pixel J to pixel Q) are output as the correction detection area signal 4.
[0025]
As shown in FIG. 3, the maximum value / minimum value detecting means 5 includes a peripheral maximum value detecting block 51 for detecting the peripheral maximum value 6 and a peripheral minimum value detecting block 52 for detecting the peripheral minimum value 7. Yes. The peripheral maximum value detection block 51 is the minimum of the values (LG, LH, LJ, LK) of peripheral pixels (pixel G, pixel H, pixel J, pixel K) adjacent to the correction target pixel I in the correction detection area. Values and values (LA, LB, LC, LD, LE, LF, LL, LM, LN, LO, LP, and other peripheral pixels (pixel A to pixel F, pixel L to pixel Q) in the correction detection area LQ) is compared with the maximum value, and the larger value is set as the peripheral maximum value 6. Further, the peripheral minimum value detection block 52 includes values (LG, LH, LJ, LK) of peripheral pixels (pixel G, pixel H, pixel J, pixel K) adjacent to the correction target pixel in the correction detection area. Maximum values and values (LA, LB, LC, LD, LE, LF, LL, LM, LN, LO, LP) of other peripheral pixels (pixel A to pixel F, pixel L to pixel Q) in the correction detection area , LQ) and the smaller value is set as the peripheral minimum value 7.
[0026]
Note that, when the maximum peripheral value 6 is detected, the minimum value is obtained from the values of the peripheral pixels (pixel G, pixel H, pixel J, pixel K) adjacent to the correction target pixel because the correction target pixel I is white. For example, in the case where the pixel is a defect pixel, and the defect also extends to the pixel H and the pixel J, for example, the value LH of the pixel H and the value LJ of the pixel J are large, and this value LH or value LJ is set as the peripheral maximum value. This is because, when determining whether or not the correction target pixel is a defective pixel, the detection accuracy of the defective pixel is lowered. In the present embodiment, the minimum value is selected from the values of the pixel G, the pixel H, the pixel J, and the pixel K even if the pixel H or the pixel J is a white defect pixel. Or the value of the pixel K is selected, and the detection accuracy of the defective pixel can be increased. The reason for obtaining the maximum value from the values of the peripheral pixels adjacent to the correction target pixel (pixel G, pixel H, pixel J, pixel K) when detecting the peripheral minimum value 7 is that the correction target pixel I is black. For example, in the case where the pixel is a defect pixel and the defect also extends to the pixel H and the pixel J, the value LH of the pixel H and the value LJ of the pixel J are small, and the value LH or the value LJ is set as the peripheral minimum value. This is because, when determining whether or not the correction target pixel is a defective pixel, the detection accuracy of the defective pixel is lowered. In the present embodiment, even if the pixel H or the pixel J is a black defective pixel, the maximum value is selected from the values of the pixel G, the pixel H, the pixel J, and the pixel K. The value of G or the value of pixel K is selected, and the detection accuracy of the defective pixel can be increased.
[0027]
The missing pixel determination means 9 determines whether or not the correction target pixel is a defective pixel based on the peripheral maximum value 6, the peripheral minimum value 7, and the correction target pixel value 8. First, a difference value between the correction target pixel value 8 and the peripheral maximum value 6 (correction target pixel value 8−peripheral maximum value 6) is calculated, and the difference value is compared with a threshold value 10 set from the outside. As a result of the comparison, when the difference value is larger than the threshold value 10, the correction target pixel value 8 is prominently larger than the peripheral pixel values in the correction detection area, and it is determined that the correction target pixel I is a white defect pixel. To do. When the difference value is smaller than the threshold value 10, the difference value between the peripheral minimum value 7 and the correction target pixel value 8 (the peripheral minimum value 7−correction target pixel value 8) is calculated. The set threshold value 10 is compared. As a result of comparison, when the difference value is larger than the threshold value 10, the correction target pixel value 8 protrudes and is smaller than the values of other peripheral pixels in the correction detection area, and the correction target pixel I is a black defect pixel. Is determined.
[0028]
The defective pixel determination unit 9 outputs a defective pixel determination signal 12 when determining that the correction target pixel is a white defective pixel or a black defective pixel. Also, when the defective pixel determination unit 9 determines that the correction target pixel is a white defective pixel, the defective pixel determination unit 9 outputs the peripheral maximum value 6 as the correction value 11, and when it determines that the correction target pixel is a black defective pixel, The minimum value 7 is output as the correction value 11.
[0029]
When the correction target pixel I is a white defective pixel, the switching unit 13 switches the correction target pixel value 8 to the peripheral maximum value 6 and outputs it as a defective pixel correction output signal 14 in accordance with the defective pixel determination signal 12. When the target pixel I is a black defective pixel, the correction target pixel value 8 is switched to the peripheral minimum value 7 and output as the defective pixel correction output signal 14, and when the correction target pixel I is not a defective pixel, the correction target pixel value 8 is set. This is output as a defective pixel correction output signal 14.
[0030]
With the above-described configuration, the defective pixel detection and correction apparatus according to the present embodiment does not need to check the coordinates of the defective pixel in advance and write it into the memory, and can detect and correct the defective pixel in real time, which occurs after shipment. Even a defective pixel that has been detected can be detected and corrected.
[0031]
Further, in the defective pixel detection and correction apparatus according to the present embodiment, even if the pixel adjacent to the correction target pixel is a defective pixel (white defective pixel) having a high signal level, the value of the defective pixel is selected as the peripheral maximum value. In addition, even if the pixel adjacent to the correction target pixel is a defective pixel (black defective pixel) with a low signal level, the value of the defective pixel can be prevented from being selected as the minimum peripheral value. Therefore, the defective pixel can be detected and corrected.
[0032]
(Second Embodiment)
FIG. 4 shows a defective pixel detection and correction apparatus according to the second embodiment of the present invention. The same constituent elements as those of the first embodiment shown in FIG.
[0033]
In FIG. 4, the defective pixel detection and correction apparatus according to the present embodiment is different from the defective pixel detection and correction apparatus according to the first embodiment from among a plurality of threshold candidates according to the difference value between the peripheral maximum value and the peripheral minimum value. Threshold switching means 41 for outputting the selected threshold is added.
[0034]
The threshold switching unit 41 calculates a difference value between the peripheral maximum value 6 and the peripheral minimum value 7, and a plurality of threshold candidates (first threshold candidate, second threshold candidate,... A threshold value corresponding to the difference value is selected from (candidate) and output to the defective pixel determining means 9. Specifically, when the difference value between the peripheral maximum value 6 and the peripheral minimum value 7 is large, a threshold candidate having a large value corresponding to the difference value is selected, and the difference value between the peripheral maximum value 6 and the peripheral minimum value 7 is selected. Is small, a threshold candidate having a small value corresponding to the difference value is selected.
[0035]
Therefore, the defective pixel detection and correction apparatus according to the present embodiment can prevent a normal pixel from being erroneously determined as a defective pixel when there is a large variation in pixel values in the correction detection area. When variations in pixel values are small, detection can be performed without missing missing pixels, and detection accuracy of missing pixels can be improved.
[0036]
(Third embodiment)
FIG. 5 shows a defective pixel detection and correction apparatus according to the second embodiment of the present invention. The same constituent elements as those of the first embodiment shown in FIG.
[0037]
In FIG. 5, the defective pixel detection and correction apparatus according to the present embodiment is different from the defective pixel detection and correction apparatus according to the first embodiment in pixel average calculation means 51 that calculates an average value of peripheral pixels, Accordingly, a threshold value switching means 52 for outputting a threshold value selected from a plurality of threshold value candidates is added.
[0038]
In a bright image, it is difficult to detect a white defect pixel, and it is easy to detect a black defect pixel. Conversely, in a dark image, it is easy to detect a white defect pixel and it is difficult to detect a black defect pixel. Even in the same image, there are a bright image portion and a dark image portion. However, in the defective pixel detection and correction apparatus of this embodiment, in each correction detection area, the pixel average calculation unit 51 calculates the average value of the peripheral pixel values, and the threshold switching unit 52 includes a plurality of threshold switching units 52. A threshold corresponding to the average value is selected from the input threshold candidates (threshold first candidate, threshold second candidate,..., Threshold Nth candidate), and is output to the defective pixel determination means 9. Specifically, a threshold value having a small value is selected according to the average value in a bright portion, that is, a portion having a large average value, and a threshold value candidate having a large value corresponding to the average value is selected in a dark portion, that is, a portion having a small average value. select.
[0039]
Therefore, the defective pixel detection and correction apparatus according to the present embodiment can improve the detection accuracy of the defective pixels.
[0040]
(Fourth embodiment)
FIG. 6 shows a defective pixel detection and correction apparatus according to the fourth embodiment of the present invention. The same constituent elements as those of the first embodiment shown in FIG.
[0041]
In FIG. 6, the defective pixel detection and correction apparatus according to the present embodiment performs the defective pixel determination based on the image sensor output signals 2 from a plurality of solid-state image sensors 1 that image the same subject. Further, the defective pixel detection and correction apparatus of the present embodiment includes two correction detection area generation means 3, maximum / minimum value detection means 5, missing pixel determination means 9, and switching means 13. Further, in the defective pixel detection and correction apparatus according to the present embodiment, the correction target pixel is a defective pixel by a combination of a plurality of defective pixel determination signals 12 that determine whether or not the correction target pixel is a defective pixel for each solid-state imaging device 1. A defective pixel mutual determining means 61 (second defective pixel determining means) for finally determining whether or not.
[0042]
The defective pixel mutual determination means 61 compares the defective pixel determination signal 12 for each correction target pixel having the same coordinates, and determines that two or more defective pixel determination signals 12 are both defective pixels. On the other hand, since it is stochastically very low that a defective pixel that is randomly generated is at the same coordinate, the defective pixel determination signal 12 is output to the switching unit 13 instead of determining that the correction target pixel is not a defective pixel. It is supposed not to.
[0043]
Therefore, the defective pixel correction apparatus according to the present embodiment can prevent a normal pixel in the contour portion of the image from being erroneously detected as a defective pixel.
[0044]
(Fifth embodiment (Reference example) )
FIG. 7 shows a missing pixel detection and correction apparatus according to the fifth embodiment of the present invention. FIG. 8 is a diagram for explaining the operation of the ratio average calculation means and the comparison means of the defective pixel detection and correction apparatus.
[0045]
In FIG. 7, the defective pixel detection and correction apparatus according to the present embodiment includes a correction detection area generation unit 3 connected to the solid-state imaging device 1, a ratio average calculation unit 71, a comparison unit 73, and a correction unit 74. Yes.
[0046]
In the present embodiment, defective pixel determination is performed based on an image sensor output signal 2 obtained by imaging the same subject with a plurality of solid-state image sensors 1. First, for the image sensor output signal 2 of one solid-state image sensor 1, a correction detection area as shown in FIG. 8A is generated by the correction detection area generating means 3, and pixels (pixels) in this correction detection area are generated. The values (LA1 to LQ1) of A1 to pixel Q1) are output as the correction detection area signal 4. As for the image sensor output signal of the other solid-state image sensor, as shown in FIG. 8B, a correction detection area having the same coordinates is generated, and the values of the pixels (pixel A2 to pixel Q2) in this correction detection area are generated. (LA2 to LQ2) are output as the correction detection area signal 72. Next, as shown in FIG. 8C, the correction average area signal 4 for the image sensor output signal 2 of one solid-state image sensor and the image sensor output signal of the other solid-state image sensor are obtained by the ratio average calculation means 71. In the correction detection area signal 72 for, a ratio is calculated for each pixel having the same coordinates, and an average AVE (ratio average) is obtained. Next, the comparison unit 73 compares whether the ratio of the correction target pixel I and the ratios of the pixels H and J adjacent to the left and right of the correction target pixel I are extremely large compared to the ratio average AVE. When there is a pixel whose ratio is extremely larger than the ratio average AVE among the pixels H, I, and J, it is determined that the pixel is a defective pixel. Here, the reason why the pixel H and the pixel J are also compared is to examine a continuous defect. Next, the defective pixel is corrected by replacing the value with the product of the ratio average AVE and the value of the pixel at the same coordinate in the other solid-state imaging device only for the pixel determined to be the defective pixel by the correcting unit 74.
[0047]
Therefore, the defective pixel correction apparatus according to the present embodiment can improve the detection accuracy of the defective pixel.
[0048]
(Sixth embodiment)
FIG. 9 shows a missing pixel detection and correction apparatus according to the sixth embodiment of the present invention.
[0049]
In FIG. 9, the defective pixel detection and correction apparatus according to the present embodiment includes a correction detection area generation unit 3 connected to the solid-state imaging device 1, a ratio calculation unit 91, a comparison unit 93, and a correction unit 94. .
[0050]
In the present embodiment, defective pixel determination is performed based on an image sensor output signal 2 obtained by imaging the same subject with a plurality of solid-state image sensors 1. First, with respect to the image sensor output signal 2 of one solid-state image sensor 1, the correction detection area generating unit 3 generates a correction detection area having a correction target pixel and a plurality of peripheral pixels located around the correction target pixel. Then, the value of the pixel in the correction detection area is output as the correction detection area signal 4. Next, the ratio calculation unit 91 also uses the correction detection area signal 92 of another fixed image sensor to Solid The ratio between the output of the body image sensor and the output of the other solid-state image sensor is calculated for each pixel of the same coordinate, and the correction target pixel ratio 96, the peripheral pixel ratio maximum value 97, and the peripheral pixel ratio minimum value 98 are obtained. . Next, the comparison unit 93 determines whether or not the correction target pixel ratio 96 is within the range of the peripheral pixel maximum ratio value 97 and the peripheral pixel ratio minimum value 98. When the value is out of the range, the correction target pixel is determined to be a defective pixel, and a determination result 99 is output. Next, the correction unit 94 replaces the value of the correction target pixel determined to be a defective pixel with an average value of the maximum ratio value 97 and the minimum ratio value 98.
[0051]
Therefore, the defective pixel correction apparatus of the present embodiment can prevent erroneous detection of normal pixels in the contour portion of the image as defective pixels.
[0052]
(Seventh embodiment)
FIG. 10 shows a defective pixel correction method according to the seventh embodiment of the present invention. Hereinafter, the defective pixel correction method according to the seventh embodiment of the present invention will be described with reference to FIG.
[0053]
The defective pixel correction method according to the present embodiment includes a correction detection area generation unit that selects an area having a correction target pixel and a plurality of peripheral pixels located around the correction target pixel in the output of the solid-state imaging device, This is performed by using an apparatus including a maximum value / minimum value detection unit that detects the maximum value and the minimum value of the peripheral pixels, a comparison unit that compares the values, and a correction unit that corrects the value of the correction target pixel.
[0054]
First, a correction detection area having a correction target pixel I and a plurality of peripheral pixels located around the correction target pixel I as shown in FIG. 2 is generated by the correction detection area generation means (S11). Next, the maximum value / minimum value detection means obtains the peripheral maximum value and the peripheral minimum value in the correction detection area using the formula shown in step S12 of FIG. 10 (S12). Note that LA, LB, LC, LD, LE, LF, LG, LH, LJ, LK, LL, LM, LN, LO, LP, and LQ shown in step S12 in FIG. 10 are correction detections shown in FIG. Peripheral pixels A, B, C, D, E, F, G, H, J, K, L, M, N, O, P, and Q (signal levels) are shown. The correction target pixel I has a value LI. Next, white defect pixel detection is performed by the comparison means (S13). Specifically, the difference between the correction target pixel value and the peripheral maximum value is taken and compared with a preset threshold value. In step S13, when the difference is not a value smaller than the threshold, the correction target pixel protrudes in the correction detection area and is a large value, that is, it is determined that the correction target pixel is a white defect pixel. Next, black defect pixel detection is performed by the comparison means (S14). Specifically, the difference between the value of the correction target pixel and the peripheral minimum value is taken and compared with a preset threshold value. In step S14, when the difference is not a value smaller than the threshold, the correction target pixel protrudes in the correction detection area and is a small value, that is, it is determined that the correction target pixel is a black defect pixel. When it is determined that the correction target pixel is a white defect pixel, the correction unit corrects the white defect pixel by replacing the value of the correction target pixel with the peripheral maximum value (S16). When it is determined that the correction target pixel is a black defect pixel, the correction unit corrects the black defect pixel by replacing the value of the correction target pixel with the peripheral minimum value.
[0055]
The aforementioned defective pixel correction method shown in FIG. 10 is realized by a program that causes a computer to function as the correction detection area generation means, the maximum value / minimum value detection means, the comparison means, and the correction means. It may be.
[0056]
(Eighth embodiment)
FIG. 11 shows a defective pixel correction method according to the eighth embodiment of the present invention. Hereinafter, the defective pixel correction method according to the eighth embodiment of the present invention will be described with reference to FIG.
[0057]
The defective pixel correction method according to the present embodiment includes a correction detection area generation unit that selects an area having a correction target pixel and a plurality of peripheral pixels located around the correction target pixel in the output of the solid-state imaging device, This is performed using an apparatus that includes an average calculation unit that calculates a ratio and an average of the ratio, a comparison unit that compares values, and a correction unit that corrects the value of the correction target pixel.
[0058]
In this embodiment, defective pixel determination is performed based on an image sensor output signal obtained by imaging the same subject using a plurality of solid-state image sensors. First, for the image sensor output signal of one solid-state image sensor, the correction detection area generating means has a correction target pixel I and a plurality of peripheral pixels located around the correction target pixel I as shown in FIG. The corrected detection area is generated (S21). Similarly, a correction detection area with the same coordinates is generated for the image sensor output signal of the other solid-state image sensor. Next, by the ratio average calculation means, as shown in FIG. 8, in the correction detection area for the image sensor output signal of one solid-state image sensor and the correction detection area for the image sensor output signal of the other solid-state image sensor, A ratio of values is calculated for each pixel having the same coordinate, and an average AVE (ratio average) is obtained (S22). Note that LA1 to LQ1 and LA2 to LQ2 shown in FIG. 11 are pixels A1 to Q1 in the correction detection area in the image picked up by one solid-state imaging device shown in FIG. 8A or FIG. 8B. The respective values of the pixels A2 to Q2 in the correction detection area in the image captured by the other solid-state imaging device shown in FIG. Next, the ratio LI1 / LI2 of the correction target pixel and the ratios LH1 / LH2 and LJ1 / LJ2 of the pixels adjacent to the right and left of the correction target pixel are obtained by the comparison means by the ratio average AVE obtained in step S22. It is compared whether or not the pixel is extremely large, and when there is a pixel whose ratio is extremely large compared to the ratio average AVE, it is determined that the pixel is a defective pixel (S23). Here, the reason why the pixels adjacent to the right and left of the correction target pixel are also compared is to examine a continuous defect. Next, the defective pixel is corrected by replacing the value with the product of the ratio average AVE and the pixel value of the same coordinate in the other solid-state imaging device only for the pixel determined as the defective pixel by the correcting means (S24).
[0059]
The aforementioned defective pixel correction method shown in FIG. 11 may be realized by a program that causes the computer to function as the correction detection area generation means, the ratio average calculation means, the comparison means, and the correction means. Good.
[0060]
(Ninth embodiment)
FIG. 12 shows a video signal processing apparatus according to an embodiment of the present invention.
[0061]
The video signal processing apparatus according to this embodiment includes a solid-state imaging device 1, a defective pixel detection correction apparatus 121, and an edge enhancement apparatus 122. The contour emphasizing device 122 includes contour emphasizing pixel selection means 123, contour emphasis means 124, and switching means 125.
[0062]
In FIG. 12, a defective pixel detection / correction device 121 is the defective pixel detection / correction device described in any of the first to eighth embodiments. When the defective pixel detection and correction device 121 determines that the correction target pixel is a defective pixel, the defective pixel detection signal 12 indicating that the correction target pixel is a defective pixel is used as a contour enhancement pixel selection unit of the contour enhancement device 122. 123, and outputs a defective pixel correction output signal 14 obtained by correcting the value of the correction target pixel to the contour enhancement unit 123 of the contour enhancement device 122.
[0063]
The contour enhancement pixel selection unit 123 of the contour enhancement device 122 sends the switching signal 126 adjusted for the delay amount with the defective pixel correction output signal 14 to the switching unit 125 of the contour enhancement device 122 of the contour enhancement device 122. Output. The contour emphasizing unit 124 of the contour emphasizing device 122 performs contour emphasis on the defective pixel correction output signal 14. Based on the switching signal 126, the switching unit 125 of the contour emphasizing device 122 is a defective pixel correction output signal 14 that is not contour-enhanced or a defective pixel correction output signal that is contour-enhanced by the contour emphasizing unit 124 of the contour emphasizing device 122. 14 is output as an outline emphasis pixel output signal 127. Specifically, the switching unit 125 outputs the defective pixel correction output signal 14 whose contour is emphasized by the contour emphasizing unit 124 when the defective pixel detection and correction device 121 determines that the correction target pixel is not a defective pixel. When the pixel detection correction device 121 determines that the correction target pixel is a defective pixel, the defective pixel correction output signal 14 that has been contour-enhanced by the contour enhancement unit 124 is not output, and the defective pixel from the defective pixel detection and correction device 121 is not output. The corrected output signal 14 is output as it is.
[0064]
Therefore, the video signal processing apparatus according to the present embodiment performs contour enhancement only on pixels determined to be normal pixels, and an image with a clear contour is obtained.
[0065]
【The invention's effect】
The present invention does not need to check the coordinates of the defective pixel in advance and write it to the memory, and can detect and correct the defective pixel in real time. It is possible to provide a defective pixel detection correction program and a video signal processing device.
[Brief description of the drawings]
FIG. 1 is a block diagram showing a defective pixel detection and correction apparatus according to a first embodiment of the present invention.
FIG. 2 is a diagram illustrating an example of a correction detection area.
FIG. 3 is a diagram showing an example of maximum value / minimum value detection means of a defective pixel detection correction device;
FIG. 4 is a block diagram showing a defective pixel detection correction apparatus according to a second embodiment of the present invention.
FIG. 5 is a block diagram showing a missing pixel detection correction apparatus according to a third embodiment of the present invention.
FIG. 6 is a block diagram showing a defective pixel detection correction apparatus according to a fourth embodiment of the present invention.
FIG. 7 is a block diagram showing a defective pixel detection correction apparatus according to a fifth embodiment of the present invention.
FIG. 8 is a diagram for explaining operations of a ratio average calculation unit and a comparison unit of a defective pixel detection correction apparatus according to a fifth embodiment of the present invention;
FIG. 9 is a block diagram showing a defective pixel detection correction apparatus according to a sixth embodiment of the present invention.
FIG. 10 is a block diagram showing a defective pixel detection correction method according to a seventh embodiment of the present invention.
FIG. 11 is a block diagram showing a defective pixel detection correction method according to an eighth embodiment of the present invention.
FIG. 12 is a block diagram showing a video signal processing apparatus according to an embodiment of the present invention.
[Explanation of symbols]
1 Solid-state image sensor
3 Correction detection area generation means
5 Maximum / minimum value detection means
9 Missing pixel determination means
13 Switching means
41, 52 Threshold switching means
51 pixel average calculation means
61 Missing pixel mutual judging means (second missing pixel judging means)
71 Ratio average calculation means
73, 93 Comparison means
74, 94 Correction means
91 Ratio calculation means
121 Missing pixel detection correction device
122 Outline enhancement device
123 Outline Enhancement Pixel Selection Unit of Outline Enhancement Device
124 Outline enhancement means of outline enhancement apparatus
125 Switching means for contour enhancement device

Claims

Correction detection area generating means for generating an area having a correction target pixel and a plurality of peripheral pixels located around the correction target pixel from outputs of a plurality of solid-state imaging devices that have imaged the same subject; and the plurality of peripherals Based on the maximum value / minimum value detecting means for detecting the peripheral maximum value and the peripheral minimum value for the pixel, and the peripheral maximum value, the peripheral minimum value, and the value of the correction target pixel, the correction target pixel is a defective pixel A second defective pixel that determines whether or not the correction target pixel is a defective pixel by a combination of a defective pixel determination unit that determines whether or not the pixel is a correction pixel and a plurality of defective pixel determination results determined for each solid-state imaging device when the pixel determination means, the correction target pixel is determined to be defective pixel, the correction value of the target pixel, characterized in that a switching means for switching the corrected value defective pixel detection complement Apparatus.

The maximum value / minimum value detection means compares a minimum value of a plurality of peripheral pixels adjacent to the correction target pixel in the area with a maximum value of a plurality of other peripheral pixels in the area, and has a larger value. The defective pixel detection correction apparatus according to claim 1, wherein the peripheral maximum value is set as the maximum value.

The maximum value / minimum value detecting means compares a maximum value of a plurality of peripheral pixels adjacent to the correction target pixel in the area with a minimum value of a plurality of other peripheral pixels in the area, and calculates a smaller value. The defective pixel detection and correction apparatus according to claim 1, wherein the peripheral minimum value is set as the peripheral minimum value.

When two or more of the plurality of defective pixel determination results are determinations that the correction target pixel is a defective pixel, the second defective pixel determination unit determines that the correction target pixel is not a defective pixel. The defective pixel detection and correction apparatus according to claim 1 , wherein the defective pixel detection and correction apparatus is replaced.

And correcting the detection area generating means for generating an area having a plurality of peripheral pixels located around the pixel to be corrected and the correction target pixel from the outputs of the plurality of solid-state imaging device imaging the same object, one of the solid A ratio calculating means for calculating the ratio of the output of the body imaging element and the output of the other solid-state imaging element for each pixel of the same coordinate, and for determining the ratio maximum value and the ratio minimum value of the plurality of peripheral pixels; Comparing means for comparing the ratio of the correction target pixel, the maximum ratio value, and the minimum ratio value to determine whether the correction target pixel is a defective pixel; and determining that the correction target pixel is a defective pixel And a correction unit that corrects the correction target pixel when the correction target pixel is corrected.

Generating an area having a correction target pixel and a plurality of peripheral pixels located around the correction target pixel from outputs of a plurality of solid-state imaging devices that image the same subject; and the correction target pixel in the area Comparing a maximum value of a plurality of neighboring pixels adjacent to the minimum value of a plurality of other neighboring pixels in the area and setting a smaller value as a neighboring minimum value; Comparing a minimum value of a plurality of adjacent peripheral pixels with a maximum value of a plurality of other peripheral pixels in the area and setting a larger value as a peripheral maximum value; and the peripheral maximum value and the peripheral minimum value the corrected based on the value of the pixel, the correction determining whether or not the target pixel is a defective pixel, the solid-state imaging device a plurality of defective pixel determination result of determining for each pair Determining whether or not the correction target pixel is a defective pixel by Align, when the correction target pixel is determined to be defective pixels, characterized by comprising a step of correcting the correction target pixel And deficient pixel detection correction method.

A defective pixel detection correction program for causing a computer to realize a function of detecting and correcting a defective pixel from outputs of a plurality of solid-state imaging devices that have imaged the same subject , wherein the plurality of solid-state imaging devices have captured the same subject . Correction detection area generating means for generating an area having a correction target pixel and a plurality of peripheral pixels located around the correction target pixel from the output; and a plurality of peripheral pixels adjacent to the correction target pixel in the area The maximum value is compared with the minimum values of the plurality of other peripheral pixels in the area, and the smaller value is set as the peripheral minimum value, and the minimum value of the plurality of peripheral pixels adjacent to the correction target pixel in the area And a maximum value / minimum value detecting means for comparing a maximum value of a plurality of other peripheral pixels in the area and setting a larger value as a peripheral maximum value; and Based on the value and the peripheral minimum value and the value of the correction object pixel, the a defective pixel determination means for determining the correction target pixel whether a defective pixel, a plurality of defects was determined for each of the solid-state imaging device A second defective pixel determining unit that determines whether or not the correction target pixel is a defective pixel based on a combination of pixel determination results; and when the correction target pixel is determined to be a defective pixel, A defective pixel detection correction program for causing the computer to function as correction means for correcting.

A video signal processing apparatus including a contour enhancement unit that performs pixel contour enhancement, based on a defective pixel determination result output from the defective pixel detection correction device according to any one of claims 1 to 5 . A video signal processing apparatus, comprising: a switching means for switching so that only the normal pixels are contour-enhanced by the contour-enhancing means and the missing pixels are not contour-enhanced.