JPH01120180A - Automatic exposure controller - Google Patents
Automatic exposure controllerInfo
- Publication number
- JPH01120180A JPH01120180A JP62277384A JP27738487A JPH01120180A JP H01120180 A JPH01120180 A JP H01120180A JP 62277384 A JP62277384 A JP 62277384A JP 27738487 A JP27738487 A JP 27738487A JP H01120180 A JPH01120180 A JP H01120180A
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- Prior art keywords
- area
- exposure
- photometric area
- photometric
- circuit
- 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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Links
- 238000001514 detection method Methods 0.000 claims description 69
- 238000000034 method Methods 0.000 abstract description 12
- 238000005375 photometry Methods 0.000 description 61
- 238000010586 diagram Methods 0.000 description 7
- 230000007274 generation of a signal involved in cell-cell signaling Effects 0.000 description 3
- 239000002131 composite material Substances 0.000 description 2
- 230000003287 optical effect Effects 0.000 description 2
- 230000001360 synchronised effect Effects 0.000 description 2
- 230000000694 effects Effects 0.000 description 1
- 208000015181 infectious disease Diseases 0.000 description 1
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- Exposure Control For Cameras (AREA)
Abstract
Description
【発明の詳細な説明】
（発明の利用分野）
本発明は、ビデオカメラ等のカメラに配置される自動露
光制御装置の改良に関するものである。DETAILED DESCRIPTION OF THE INVENTION (Field of Application of the Invention) The present invention relates to an improvement in an automatic exposure control device disposed in a camera such as a video camera.
（発明の背景）
ビデオカメラにおける露光量は露光時間とその時の絞り
開口とによって決まる。露光時間は一般に１フイ一ルド
期間であり、ＮＴＳＣ方式において１／６０秒、ＰＡＬ
方式において１１５０秒である。従って露光制御を行う
場合、一般に光学系の絞りを調整することにより行って
いる。又撮像素子として、電子シャッタ動作が可能なも
のを使用する場合は、この電子シャッタを制御して露光
時間を制御することも可能である。(Background of the Invention) The amount of exposure in a video camera is determined by the exposure time and the aperture aperture at that time. Exposure time is generally one field period, 1/60 second in NTSC system, PAL
In the method, it is 1150 seconds. Therefore, exposure control is generally performed by adjusting the aperture of the optical system. Furthermore, if an image sensor capable of electronic shutter operation is used, it is also possible to control the electronic shutter to control the exposure time.
以上のことから分かるようにこの種の露光制御装置は、
映像信号レベルが常に一定となるように光学系の絞り或
は撮像素子の電子シャッタをフィードバック制御するも
のである。第７図に従来の自動露光制御装置の一例を示
す。腰回において、１はレンズ、２は絞り（後述の撮像
素子が固体撮像素子であった場合は電子シャッタでも良
い）制御を行い、露光量の制御を行う露光制御回路、３
は撮像素子、４は露光制御信号を発生する信号レベル検
出回路、５は露光制御目標値に相当するレベルを発生す
る電源、６は映像信号出力端子である。As can be seen from the above, this type of exposure control device
This system performs feedback control of the aperture of the optical system or the electronic shutter of the image sensor so that the video signal level is always constant. FIG. 7 shows an example of a conventional automatic exposure control device. At the waist, 1 is a lens, 2 is an exposure control circuit that controls an aperture (an electronic shutter may also be used if the image sensor described later is a solid-state image sensor) and controls the amount of exposure, 3
4 is an image sensor, 4 is a signal level detection circuit that generates an exposure control signal, 5 is a power source that generates a level corresponding to an exposure control target value, and 6 is a video signal output terminal.
前記構成において、レンズ１を通過した被写体像は撮像
素子３に入射し、ここで映像信号に変換されて信号レベ
ル検出回路４に入力する。又前記映像信号は映像信号出
力端子６を介してビデオ信号を生成するための不図示の
信号処理回路へ入力する。前記信号レベル検出回路４は
入力する映像信号に基づいて露光制御信号を生成し、該
信号を露光制御回路２へ出力する。すると該露光制御回
路２は、前記露光制御信号をもって露光の尺度とし、こ
れが常に露光制御目標値に相当するレベルを発生する電
源５より入力する一定のレベル値となるように制御する
。In the above configuration, the subject image that has passed through the lens 1 is incident on the image sensor 3, where it is converted into a video signal and input to the signal level detection circuit 4. Further, the video signal is inputted via the video signal output terminal 6 to a signal processing circuit (not shown) for generating a video signal. The signal level detection circuit 4 generates an exposure control signal based on the input video signal, and outputs the signal to the exposure control circuit 2. Then, the exposure control circuit 2 uses the exposure control signal as a measure of exposure, and controls it so that it always becomes a constant level value inputted from a power source 5 that generates a level corresponding to the exposure control target value.
ここで、前記信号レベル検出回路４では例えば以下の２
種類の内のいずれかの測光が行われてた。Here, in the signal level detection circuit 4, for example, the following two
Photometry of one of the types was performed.
１）全面平均測光
２）ピーク測光
しかし、前記各測光方式においてはそれぞれ次のような
欠点を有していた。1) Overall average photometry 2) Peak photometry However, each of the above photometry methods had the following drawbacks.
１）においては、空或は光源のような高輝度部が画面内
を大きく占めた場合映したい対象物が黒く沈み、又背景
が暗くなった場合被写体が白とびを生じる。In 1), if a high brightness area such as the sky or a light source occupies a large area of the screen, the object to be photographed will appear black, and if the background becomes dark, the object will be overexposed.
２）においては、画面内の一部に僅かでも高輝度部が入
った来た場合、画面全体が暗く沈む。In 2), if even a small portion of the screen has a high brightness area, the entire screen becomes dark.
また、前記１）、２）での欠点をある程度解消できるも
のとして、
３）中央重点測光或はスポット（部分）測光なる測光方
式もあるが、この測光方式においても、例えばカメラを
若干動かした場合や被写体自体が画面内において動くこ
とにより、画面中央或はスポット測光部から該被写体が
外れると、露光が変化し、画面の明るさが変化して不自
然な印象な与久るという欠点を有していた。これは特に
背景とのコントラストが大きい場合、顕著に表れていた
。また、前記被写体の画面内での位置変化に対応できる
構成とした場合においても、被写体以外の対象物は無視
されるため、被写体に最適露光となっても画面全体とし
てみた場合、最適であるとは必ずしも言えない。There is also a metering method called 3) center-weighted metering or spot (partial) metering that can overcome the drawbacks of 1) and 2) above to some extent, but even with this metering method, for example, if the camera is moved slightly, If the subject moves within the screen and the subject moves away from the center of the screen or from the spot metering section, the exposure will change and the brightness of the screen will change, giving an unnatural impression for a long time. Was. This was especially noticeable when the contrast with the background was large. Furthermore, even when the configuration is configured to accommodate changes in the position of the subject within the screen, objects other than the subject are ignored, so even if the exposure is optimal for the subject, it may not be optimal when looking at the entire screen. cannot necessarily be said.
（発明の目的）
本発明の目的は、画面内のどこに被写体が位置したとし
ても、該被写体はもちろん、画面全体に対してもより最
適な露光を与えることのできる自動露光制御装置を提供
することである。(Object of the Invention) An object of the present invention is to provide an automatic exposure control device that can provide more optimal exposure not only to the subject but also to the entire screen, no matter where the subject is located within the screen. It is.
（発明の特徴）
上記目的を達成するために、本発明は、画面内において
移動可能な検出領域の内外でそれぞれ得られる映像信号
中の所定の周波数成分の差情報を算出する算出手段と、
該算出手段により算出された前記検出領域の異なる位置
におけるそれぞれの差情報より撮影画面内での被写体の
位置を判定する判定手段と、該判定手段にて判定された
被写体の位置に測光領域を設定する測光領域追尾手段と
、被写体の位置に設定された前記測光領域、それ以外の
領域或は測光領域を含む全領域での露光情報をそれぞれ
検出する露光検出手段と、前記測光領域とそれ以外の領
域、或は測光領域と該測光領域を含む全領域にて得られ
る映像信号中の所定の周波数成分の差情報を算出し、こ
の差情報に基づいて前記露光検出手段よりのそれぞれの
出力に重み付けする重み付け手段と、該重み付け手段に
より出力されるそれぞれの演算値をもって露光制御を行
う露光制御手段とを設け、以て、画面内における被写体
の位置変化が生じた場合、該被写体の位置まで測光領域
を移動させ、且つその時の測光領域とそれ以外の領域、
或は測光領域と該測光領域を含む全領域にて得られる映
像信号中の所定の周波数成分の差情報に基づいて露光制
御の為の信号を生成するようにしたことを特徴とする。(Features of the Invention) In order to achieve the above object, the present invention provides a calculation means for calculating difference information of predetermined frequency components in a video signal obtained inside and outside a movable detection area within a screen;
determining means for determining the position of the subject within the photographic screen from difference information at different positions of the detection area calculated by the calculating means; and setting a photometric area at the position of the subject determined by the determining means. a photometric area tracking means that detects exposure information in the photometric area set at the subject position, other areas, or the entire area including the photometric area; calculating the difference information of a predetermined frequency component in the video signal obtained in the area, or the photometric area and the entire area including the photometric area, and weighting each output from the exposure detection means based on this difference information. and an exposure control means that performs exposure control using the calculated values outputted by the weighting means, so that when the position of the subject changes within the screen, the photometry area is adjusted to the position of the subject. , and the photometry area and other areas at that time,
Alternatively, the present invention is characterized in that a signal for exposure control is generated based on difference information of a predetermined frequency component in a video signal obtained in a photometric area and the entire area including the photometric area.
（発明の実施例）
以下、本発明を図示の実施例に基づいて詳細に説明する
。(Embodiments of the Invention) Hereinafter, the present invention will be described in detail based on illustrated embodiments.
第２図は本発明の一実施例を示すブロック図であり、第
７図と同じ部分は同一符号を付しである。FIG. 2 is a block diagram showing an embodiment of the present invention, and the same parts as in FIG. 7 are given the same reference numerals.
第７図と異なる部分は、測光領域位置制御回路７、該回
路に同期信号（水平及び垂直同期信号）を伝達する同期
信号入力端子８を付加した点と、信号レベル検出回路を
前記測光領域位置制御回路７から指示される測光領域の
内外の輝度差に基づいて露光制御信号を生成する信号レ
ベル検出回路９としたところである。The differences from FIG. 7 include the addition of a photometric area position control circuit 7, a synchronization signal input terminal 8 for transmitting synchronization signals (horizontal and vertical synchronization signals) to the circuit, and the addition of a signal level detection circuit to the photometry area position control circuit 7. The signal level detection circuit 9 generates an exposure control signal based on the luminance difference between the inside and outside of the photometric area instructed by the control circuit 7.
レンズ１を通過した被写体像は撮像素子３に入射し、こ
こで映像信号に変換されて信号レベル検出回路９に入力
すると共に、測光領域位置制御回路７にも入力する。測
光領域位置制御回路７は測光領域を画面内での被写体に
追尾するように位置制御（詳細は第１図（ａ）にて行う
）し、同期信号と同期したＨＶ複合信号として画面内で
の測光領域の位置を示す測光領域位置信号を信号レベル
検出回路９に出力する。すると前記信号レベル検出回路
９は前記撮像素子３よりの映像信号と前記測光領域位置
信号によって指定された測光領域の内外の輝度差とに基
づいて露光制御を行うのに必要となる露光制御信号を生
成（詳しくは第１図（ｂ）にて行う）し、露光制御回路
２へ出力する。露光制御回路２は前述したように、前記
露光制御信号をもって露光の尺度とし、これが常に露光
制御目標値に相当するレベルを発生する電源５より入力
する一定のレベル値となるように、例えば絞りの開口状
態を制御する。The subject image that has passed through the lens 1 is incident on the image sensor 3, where it is converted into a video signal and input to the signal level detection circuit 9, as well as to the photometric area position control circuit 7. The photometric area position control circuit 7 controls the position of the photometric area so that it tracks the subject within the screen (details are shown in FIG. A photometric area position signal indicating the position of the photometric area is output to the signal level detection circuit 9. Then, the signal level detection circuit 9 generates an exposure control signal necessary for performing exposure control based on the video signal from the image sensor 3 and the brightness difference between the inside and outside of the photometry area designated by the photometry area position signal. (details are shown in FIG. 1(b)) and output to the exposure control circuit 2. As described above, the exposure control circuit 2 uses the exposure control signal as a measure of exposure, and adjusts the aperture, for example, so that this becomes a constant level value inputted from the power supply 5 that always generates a level corresponding to the exposure control target value. Control the opening state.
第１図（ａ）は前記測光領域位置制御回路７の構成例を
示すものであり、腰回において、１０１は測光領域内輝
度レベル検出回路、１０２は前記測光領域周辺の輝度レ
ベルを検出する測光領域外輝度レベル検出回路、１０３
は内外の輝度レベルの差を算出する引算回路、１０４は
測光領域内外の輝度差よりその時の画面内での被写***
置を判定する被写***置判定回路、１０５は算定された
被写***置まで測光領域を移動させる測光領域移動回路
、１０６は画面内での現在の測光領域の位置を示す信号
（同期信号に同期したＨＶ複合信号として）を発生する
測光領域位置信号発生回路である。FIG. 1(a) shows an example of the configuration of the photometric area position control circuit 7. In the waist, 101 is a photometric area brightness level detection circuit, and 102 is a photometer for detecting the brightness level around the photometric area. Out-of-area brightness level detection circuit, 103
104 is a subtraction circuit that calculates the difference between the brightness levels inside and outside the photometry area; 104 is a subject position determination circuit that determines the subject position within the screen at that time from the difference in brightness inside and outside the photometry area; and 105 is a photometry area that extends to the calculated subject position. The photometric area moving circuit 106 is a photometric area position signal generating circuit that generates a signal (as an HV composite signal synchronized with a synchronization signal) indicating the current position of the photometric area within the screen.
次にここでの動作を第３図を用いて説明する。Next, the operation here will be explained using FIG.
尚第３図において、Ａは画面（撮影画面）、Ｂは測光領
域、Ｃは画面Ａ内に映し出された被写体である。In FIG. 3, A is a screen (photographing screen), B is a photometric area, and C is an object projected on screen A.
映像信号（輝度成分）が入力することにより、測光領域
内輝度レベル検出回路１０１は測光領域Ｂ（例えばこの
測光領域Ｂは初期時には画面Ａの中央に位置する）内の
輝度レベル検出を行い、測光領域外輝度レベル検出回路
１０２は測光領域Ｂの周辺の輝度レベル検出を行い、そ
れぞれその検出結果を引算回路１０３へ出力する。引算
回路１Ｏ３はその差を算出し、被写***置判定回路１゜
４へ出力する。被写***置判定回路１０４は、入力する
前記内外の輝度レベル差情報（の絶対値）を−旦保持す
ると共に、測光領域移動回路１０５、測光領域位置信号
発生回路１０６を介して画面Ａ内での測光領域Ｂの位置
をゲート制御等により上下左右にシフトさせ、それぞれ
の位置での内外の輝度差の算出結果をさらに得、これら
の５つの輝度差情報の内で最も差の大きかった位置が被
写体Ｃの位置である判定する。測光領域移動回路１０５
は前記判定された被写***置まで測光領域Ｂを移動させ
る（このような動作は例えばｌフィールド毎に行われる
）。これにより画面Ａ内での被写体Ｃの動きに対してリ
アルタイムで測光領域Ｂの追尾を行うことが可能となる
。尚本実施例では、被写体Ｃの位置を判定するのに必要
となる画面Ａを内外に区分する追尾用の検出領域は特に
殺けておらず、測光領域Ｂを共用する構成としている。When a video signal (luminance component) is input, the photometry area brightness level detection circuit 101 detects the brightness level in photometry area B (for example, this photometry area B is initially located at the center of screen A), and performs photometry. The out-of-area brightness level detection circuit 102 detects the brightness level around the photometric area B, and outputs the detection results to the subtraction circuit 103. The subtraction circuit 1O3 calculates the difference and outputs it to the subject position determination circuit 1.4. The subject position determination circuit 104 temporarily holds (absolute value of) the input internal and external luminance level difference information, and also performs photometry within the screen A via a photometry area movement circuit 105 and a photometry area position signal generation circuit 106. The position of area B is shifted vertically and horizontally by gate control, etc., and the calculation results of the brightness difference inside and outside at each position are further obtained, and the position with the largest difference among these five brightness difference information is the subject C. It is determined that the position is. Photometric area movement circuit 105
moves the photometry area B to the determined subject position (such an operation is performed every 1 fields, for example). This makes it possible to track the photometric area B in real time with respect to the movement of the subject C within the screen A. In this embodiment, the tracking detection area that divides the screen A into the inside and outside, which is necessary for determining the position of the subject C, is not particularly limited, and the photometry area B is shared.
測光領域位置信号発生回路１０６は前述のようにして決
まった最終的な画面Ａ内での測光領域Ｂの位置を示す測
光領域位置信号を第２図に示した信号レベル検出回路９
へ出力する。The photometric area position signal generation circuit 106 generates a photometric area position signal indicating the final position of the photometric area B within the screen A determined as described above, and the signal level detection circuit 9 shown in FIG.
Output to.
第４図は第２図図示測光領域位置制御回路７の他の構成
例を示すものであり、腰回において、２０１は測光領域
内高周波成分検出回路、２０２は前記測光領域周辺の高
周波成分を検出する測光領域外高周波成分検出回路、２
０３は内外の高周波成分の差を算出する引算回路、２０
４は測光領域内外の高周波成分の差よりその時の画面内
での被写***置を判定する被写***置判定回路、２０５
は算定された被写***置まで測光領域を移動させる測光
領域移動回路、２０６は画面内での現在の測光領域の位
置を示す信号（同期信号に同期したＨＶ複合信号として
）を発生する測光領域位置信号発生回路である。FIG. 4 shows another example of the configuration of the photometric area position control circuit 7 shown in FIG. High frequency component detection circuit outside the photometric range, 2
03 is a subtraction circuit that calculates the difference between internal and external high frequency components, 20
4 is a subject position determination circuit 205 that determines the subject position within the screen at that time based on the difference between high frequency components inside and outside the photometry area;
206 is a photometric area moving circuit that moves the photometric area to the calculated subject position, and 206 is a photometric area position signal that generates a signal (as an HV composite signal synchronized with a synchronization signal) indicating the current position of the photometric area within the screen. This is a generation circuit.
不図示のバンドパスフィルタを介して映像信号中の高周
波成分の高域側である高周波成分が入力することにより
、測光領域内高周波成分検出回路２０１は測光領域Ｂ内
の高周波成分検出を行い、測光領域外高周波成分検出回
路２０２は測光領域Ｂの周辺の高周波成分検出を行い、
それぞれその検出結果を引算回路２０３へ出力する。引
算回路２０３はその差を算出し、被写***置判定回路２
０４へ出力する。被写***置判定回路２０４は、入力す
る前記内外の高周波成分の差情報（の絶対値）を−旦保
持すると共に、測光領域移動回路２０５、測光領域位置
信号発生回路２０６を介して画面Ａ内での測光領域Ｂの
位置をゲート制御等により上下左右にシフトさせ、それ
ぞれの位置での内外の輝度差の算出結果をさらに得、こ
れらの５つの高周波成分の差情報の内で最も差の大きか
った位置が被写体Ｃの位置である判定する。測光領域移
動回路２０５は前記判定された被写***置まで測光領域
Ｂを移動させる。測光領域位置信号発生回路２０６は前
述のようにして決まった最終的な画面Ａ内での測光領域
Ｂの位置を示す測光領域位置信号を第２図に示した信号
レベル検出回路９へ出力する。By inputting a high frequency component on the high frequency side of the high frequency component in the video signal through a bandpass filter (not shown), the photometric area high frequency component detection circuit 201 detects the high frequency component within the photometric area B, and performs photometry. The out-of-area high frequency component detection circuit 202 detects high frequency components around the photometric area B.
The respective detection results are output to the subtraction circuit 203. The subtraction circuit 203 calculates the difference, and the subject position determination circuit 2
Output to 04. The subject position determination circuit 204 temporarily holds (the absolute value of) the input difference information between the internal and external high frequency components, and also determines the difference information within the screen A via the photometric area moving circuit 205 and the photometric area position signal generating circuit 206. The position of photometry area B is shifted vertically and horizontally by gate control, etc., and the calculation results of the difference in brightness between the inside and outside at each position are further obtained, and the position where the difference is the largest among the difference information of these five high frequency components is calculated. It is determined that is the position of subject C. The photometric area moving circuit 205 moves the photometric area B to the determined subject position. The photometric area position signal generation circuit 206 outputs a photometric area position signal indicating the final position of the photometric area B within the screen A determined as described above to the signal level detection circuit 9 shown in FIG.
このように高周波成分をもって被写体Ｃの位置を検出す
る方式は、例えばビデオカメラから被写対象までの距離
と、背景までの距離との差が大きく、ピントが被写体に
しか合わないような場合に有効である。この例を第５図
に示す。画面Ａの中の被写体Ｃにピントが合っている場
合、この位置が画面Ａ内の高周波成分の最大位置となり
、該被写体Ｃの位置まで測光領域Ｂが移動させられるこ
とになる。対象Ｃ１は被写体Ｃより遠方にあり、ピント
が合わず高周波成分は小さく、対象Ｃ２は逆に至近側に
あり、やはりピントが合わず高周波成分は小さい、従っ
て、測光領域Ｂは常にピントが合っていて高周波成分が
大きい被写体Ｃの位置に合わせられることになる。This method of detecting the position of subject C using high-frequency components is effective, for example, when there is a large difference between the distance from the video camera to the subject and the distance to the background, and the focus is only on the subject. It is. An example of this is shown in FIG. When the subject C on the screen A is in focus, this position becomes the maximum position of the high frequency component on the screen A, and the photometry area B is moved to the position of the subject C. Object C1 is farther away than object C and is out of focus, so the high frequency component is small.Object C2, on the other hand, is closer and also out of focus and the high frequency component is small.Therefore, photometry area B is always in focus. Thus, the position of the subject C having a large high frequency component is adjusted.
前記測光領域位置制御回路７より測光領域位置信号が入
力すると共に、撮像素子３より全画面を通過する映像信
号が入力する信号レベル検出回路９の構成例を第１図（
ｂ）に示す。腰回において、３０１は測光領域内輝度レ
ベル検出回路、３０２は測光領域外輝度レベル検出回路
、３０３は測光領域内露光検出回路、３０４は測光領域
外露光検出回路、３０５は測光領域内外の輝度差を算出
する引算回路、３０６は前記引算回路３０５よりの値に
応じて測光領域内露光検出回路３０３及び測光領域外露
光検出回路３０４よりの各信号のゲインのコントロール
を行うゲインコントローラ、３０７．３０８はゲイン可
変アンプ、３０９は加算回路である。An example of the configuration of the signal level detection circuit 9 to which the photometric area position signal is inputted from the photometric area position control circuit 7 and the video signal passing through the entire screen from the image sensor 3 is inputted is shown in FIG.
Shown in b). In the waist rotation, 301 is a brightness level detection circuit within the photometry area, 302 is a brightness level detection circuit outside the photometry area, 303 is an exposure detection circuit within the photometry area, 304 is an exposure detection circuit outside the photometry area, and 305 is a brightness difference inside and outside the photometry area. 306 is a gain controller that controls the gain of each signal from the photometry area exposure detection circuit 303 and the photometry area outside exposure detection circuit 304 according to the value from the subtraction circuit 305; 307. 308 is a variable gain amplifier, and 309 is an adder circuit.
前記測光領域内露光検出回路３０３及び測光領域外露光
検出回路３０４は画面内の各々の領域の平均値或はピー
ク値等の演算処理を行い、露光を制御するための信号を
出力するものであり、これら出力はそれぞれゲイン可変
アンプ３０７，３０８を通して加算回路３０９に入力し
、露光制御信号が生成される。ここで、測光領域内露光
検出回路３０３の出力なＭ、測光領域外露光検出回路３
０４の出力なＮ、ゲイン可変アンプ３０７，３０８の各
々のゲインなＫｌ、に２、露光制御信号をＬとすると
Ｌ＝Ｋ １・Ｍ＋に２・Ｎ
となる。ゲインコントローラ３０６は、このに１、に２
を測光領域内外の輝度差に応じて制御し、Ｍ、Ｈの重み
付けを変化させる０例えば測光領域Ｂ内とその周辺の輝
度差が小さい時は、Ｋ１を小さくして測光領域Ｂ内の情
報の重み付けを小さくし、画面全体の情報を考慮して露
光制御を行う、また測光領域Ｂ内とその周辺の輝度差が
大きい場合、すなわちハイコントラスト画像と判断でき
る場合は、Ｋ１を大きくして測光領域Ｂ内の情報の重み
付けを大きくし、被写体を重点として露光制御を行う。The exposure detection circuit 303 within the photometry area and the exposure detection circuit 304 outside the photometry area perform arithmetic processing such as the average value or peak value of each area within the screen, and output signals for controlling exposure. , these outputs are input to an adder circuit 309 through variable gain amplifiers 307 and 308, respectively, and an exposure control signal is generated. Here, the output M of the exposure detection circuit 303 inside the photometry area, the output M of the exposure detection circuit 303 outside the photometry area
04, the gain Kl of each of the variable gain amplifiers 307 and 308 is 2, and the exposure control signal is L, L=K1.M+2.N. The gain controller 306 has 1 and 2
is controlled according to the brightness difference inside and outside the photometry area, and the weighting of M and H is changed. Decrease the weighting and perform exposure control taking into account the information of the entire screen.Also, if there is a large difference in brightness between photometry area B and its surroundings, that is, if it can be determined that the image is a high contrast image, increase K1 and control the exposure by considering the information of the entire screen. Increase the weighting of the information in B and perform exposure control with the subject as the main focus.
尚第１図（ｂ）の構成において、前記測光領域外輝度レ
ベル検出回路３０２と測光領域外露光検出回路３０４は
それぞれ全画面輝度レベル検出回路、全画面露光検出回
路としても良い。In the configuration shown in FIG. 1(b), the outside photometry area brightness level detection circuit 302 and the outside photometry area exposure detection circuit 304 may be a full screen brightness level detection circuit and a full screen exposure detection circuit, respectively.
第６図は信号レベル検出回路９の他の構成例を示すもの
であり、第１図（ｂ）と同じ部分は同一符号を付しであ
る。腰回において、４０１は全画面露光検出回路、４０
２は測光方式判断回路、４０３は切換えスイッチである
。FIG. 6 shows another example of the configuration of the signal level detection circuit 9, and the same parts as in FIG. 1(b) are given the same reference numerals. At the waist, 401 is a full-screen exposure detection circuit;
2 is a photometry method determination circuit, and 403 is a changeover switch.
第１図（ｂ）と異なる部分は、測光方式判断回路４０２
が引算回路３０５よりの測光領域Ｂ内とその周辺の輝度
差に応じて測光領域内輝度レベル検出回路３０３の出力
と全画面露光検出回路４０１の出力とのいずれかを切換
えスイッチ４０３を介して選択するようにしたところで
ある。The difference from FIG. 1(b) is the photometry method determination circuit 402.
The subtraction circuit 305 selects either the output of the intra-photometric area brightness level detection circuit 303 or the output of the full-screen exposure detection circuit 401 according to the difference in brightness between the inside and the surrounding area of the photometric area B via the switch 403. This is where you get to choose.
例えば測光領域Ｂ内とその周辺の輝度差が小さく、低コ
ントラスト画像と判断できる場合は、測光方式判断回路
４０２は切換えスイッチ４０３を介して全画面露光検出
回路４０１よりの出力を選択し、ハイコントラスト画像
と判断できる場合は、切換えスイッチ４０３を介して測
光領域内露光検出回路３０３よりの出力を選択して被写
体に露光を合せるようにする。尚この切換えのスレッシ
ョルド値は測光方式判断回路４０３内に設定されている
。For example, if the luminance difference between the photometry area B and its surroundings is small and it can be determined that the image is a low contrast image, the photometry method judgment circuit 402 selects the output from the full screen exposure detection circuit 401 via the changeover switch 403, and If it can be determined that it is an image, the output from the photometric area exposure detection circuit 303 is selected via the changeover switch 403 to match the exposure to the subject. Note that the threshold value for this switching is set in the photometry method determination circuit 403.
本実施例によれば、画面Ａ内における被写体Ｃの位置を
測光領域Ｂ内とその周辺（測光領域内外）の輝度差或は
高周波成分の差によって検出し、該位置に測光領域Ｂを
追尾せしめるようにすると共に、その時の測光領域Ｂ内
とその周辺或は測光領域Ｂ内と全画面の輝度差に基づい
て各領域にて得られる露光情報の重み付けを変化させる
（第６図実施例においては、いずれか一方の重み付けを
零（０）にしている）ようにしたから、被写体Ｃ及び画
面全体に対して最適な露光を与えることができる。つま
り被写体Ｃが動いても、或はカメラをパン、ティルトさ
せた場合においても、自然な画像とすることが可能とな
る。According to this embodiment, the position of the subject C within the screen A is detected based on the difference in brightness or high frequency component between the photometric area B and its surroundings (inside and outside the photometric area), and the photometric area B is made to track the position. At the same time, the weighting of the exposure information obtained in each area is changed based on the luminance difference between the inside of the photometric area B and its surroundings, or between the inside of the photometric area B and the entire screen at that time (in the embodiment shown in FIG. 6). , the weighting of one of them is set to zero (0)), it is possible to give optimum exposure to the subject C and the entire screen. In other words, even if the subject C moves or the camera is panned or tilted, it is possible to obtain a natural image.
（発明と実施例の対応）
本実施例において、測光領域内輝度レベル検出回路１０
１．測光領域外輝度レベル検出回路１０２、引算回路１
０３、及び測光領域内高周波成分検出回路２０１．測光
領域外高周波成分検出回路２０２、引算回路２０３が本
発明の算出手段に、被写***置判定回路１０４，２０４
が判定手段に、測光領域移動回路１０５，２０５が測光
領域追尾手段に、測光領域内輝度レベル検出回路３０１
からゲイン可変アンプ３０８まで、及び全画面露光検出
回路４０１．測光方式判断回路４０２が重み付け手段に
、加算回路３０９．切換えスイッチ４０３．電源５及び
露光制御回路２が露光制御手段に、それぞれ相当する。(Correspondence between the invention and the embodiments) In this embodiment, the luminance level detection circuit 10 in the photometric area
1. Brightness level detection circuit outside photometry area 102, subtraction circuit 1
03, and a high frequency component detection circuit within the photometric region 201. The high frequency component detection circuit 202 outside the photometric area and the subtraction circuit 203 are used as the calculation means of the present invention, and the subject position determination circuits 104 and 204 are used as the calculation means of the present invention.
is the determining means, the photometric area moving circuits 105 and 205 are the photometric area tracking means, and the intra-photometric area luminance level detection circuit 301
to the variable gain amplifier 308, and the full screen exposure detection circuit 401. The photometry method determining circuit 402 serves as a weighting means, and the adding circuit 309. Changeover switch 403. The power source 5 and the exposure control circuit 2 each correspond to exposure control means.
（発明の効果）
以上説明したように、本発明によれば１画面内において
移動可能な検出領域の内外でそれぞれ得られる映像信号
中の所定の周波数成分の差情報を算出する算出手段と、
該算出手段により算出された前記検出領域の異なる位置
におけるそれぞれの差情報より撮影画面内での被写体の
位置を判定する判定手段と、該判定手段にて判定された
被写体の位置に測光領域を設定する測光領域追尾手段と
、被写体の位置に設定された前記測光領域、それ以外の
領域或は測光領域を含む全領域での露光情報をそれぞれ
検出する露光検出手段と、前記測光領域とそれ以外の領
域、或は測光領域と該測光領域を含む全領域にて得られ
る映像信号中の所定の周波数成分の差情報を算出し、こ
の差情報に基づいて前記露光検出手段よりのそれぞれの
出力に重み付けする重み付け手段と、該重み付け手段に
より出力されるそれぞれの演算値をもって露光制御を行
う露光制御手段とを設け、以て、画面内における被写体
の位置変化が生じた場合、該被写体の位置まで測光領域
を移動させ、且つその時の測光領域とそれ以外の領域、
或は測光領域と該測光領域を含む全領域にて得られる映
像信号中の所定の周波数成分の差情報に基づいて露光制
御の為の信号を生成するようにしたから、画面内のどこ
に被写体が位置したとしても、該被写体はもちろん、画
面全体に対してもより最適な露光を与えることが可能と
なる。(Effects of the Invention) As explained above, according to the present invention, there is provided a calculation means for calculating difference information of predetermined frequency components in a video signal obtained inside and outside a movable detection area within one screen;
determining means for determining the position of the subject within the photographic screen from difference information at different positions of the detection area calculated by the calculating means; and setting a photometric area at the position of the subject determined by the determining means. a photometric area tracking means that detects exposure information in the photometric area set at the subject position, other areas, or the entire area including the photometric area; calculating the difference information of a predetermined frequency component in the video signal obtained in the area, or the photometric area and the entire area including the photometric area, and weighting each output from the exposure detection means based on this difference information. and an exposure control means that performs exposure control using the calculated values outputted by the weighting means, so that when the position of the subject changes within the screen, the photometry area is adjusted to the position of the subject. , and the photometry area and other areas at that time,
Alternatively, since the signal for exposure control is generated based on the difference information of a predetermined frequency component in the video signal obtained in the photometry area and the entire area including the photometry area, it is possible to determine where the subject is in the screen. Even if the subject is located, it is possible to provide more optimal exposure not only to the subject but also to the entire screen.
第１図（ａ）は第２図図示測光領域位置制御回路の構成
例を示すブロック図、第１図（ｂ）は第２図図示信号レ
ベル検出回路の構成例を示すブロック図、第２図は本発
明の一実施例を示すブロック図、第３図は第１図（ａ）
構成例における画面内で位置変化する被写体に対する測
光領域追尾を説明する図、第４図は第２図図示測光領域
位置制御回路の他の構成例を示すブロック図、第５図は
第４図構成例における画面内で位置変化する被写体に対
する測光領域追尾を説明する図、第６図は第２図図示信
号レベル検出回路の他の構成例を示すブロック図、第７
図は従来の自動露光制御装置の一例を示すブロック図で
ある。
１・・・・・・レンズ、２・・・・・・露光制御回路、
３・・・・・・撮像素子、５・・・・・・電源、７・・
・・・・測光領域位置制御回路、９・・・・・・信号レ
ベル検出回路、１０１・・・・・・測光領域内輝度レベ
ル検出回路、１０２・・・・・・測光領域外輝度レベル
検出回路、１０３・・・・・・引算回路、１０４・・・
・・・被写***置判定回路、１０５・・・・・・測光領
域移動回路、２０１・・・・・・測光領域内高周波成分
検出回路、２０２・・・・・・測光領域外高周波成分検
出回路、２０３・・・・・・引算回路、２０４・・・・
・・被写***置判定回路、２０５・・・・・・測光領域
移動回路、３０１・・・・・・測光領域内輝度レベル検
出回路、３０２・・・・・・測光領域外輝度レベル検出
回路、３０３・・・・・・測光領域内露光検出回路、３
０４・・・・・・測光領域外露光検出回路、３０５・・
・・・・引算回路、３０６・・・・・・ゲインコントロ
ーラ、３０７，３０８・・・・・・ゲイン可変アンプ、
４０１・・・・・・全画面露光検出回路、４０２・・・
・・・測光方式判断回路。
第 １ 図（ｂ） 屏洸印誰冒信号露光ｖＩ
御信号
第２図
第３図1(a) is a block diagram showing an example of the configuration of the photometric area position control circuit shown in FIG. 2, FIG. 1(b) is a block diagram showing an example of the configuration of the signal level detection circuit shown in FIG. is a block diagram showing an embodiment of the present invention, and FIG. 3 is similar to FIG. 1(a).
Figure 4 is a block diagram showing another example of the configuration of the photometric area position control circuit shown in Figure 2. Figure 5 is the configuration shown in Figure 4. FIG. 6 is a block diagram showing another configuration example of the signal level detection circuit shown in FIG. 2, and FIG.
The figure is a block diagram showing an example of a conventional automatic exposure control device. 1...lens, 2...exposure control circuit,
3...Image sensor, 5...Power supply, 7...
...Photometering area position control circuit, 9...Signal level detection circuit, 101...Brightness level detection circuit within photometry area, 102...Brightness level detection outside photometry area Circuit, 103...Subtraction circuit, 104...
. . . Subject position determination circuit, 105 . . . Photometry area moving circuit, 201 . . . High frequency component detection circuit within the photometry area, 202 . 203... Subtraction circuit, 204...
...Subject position determination circuit, 205...Photometry area moving circuit, 301...Brightness level detection circuit within photometry area, 302...Brightness level detection circuit outside photometry area, 303 ...Exposure detection circuit within photometry area, 3
04...Exposure detection circuit outside photometry area, 305...
...Subtraction circuit, 306... Gain controller, 307, 308... Variable gain amplifier,
401...Full screen exposure detection circuit, 402...
...Photometering method judgment circuit. Figure 1 (b) Pingyuan Seal Whose Infection Signal Exposure vI
Signal Figure 2 Figure 3
Claims (3)
いて、画面内において移動可能な検出領域の内外でそれ
ぞれ得られる映像信号中の所定の周波数成分の差情報を
算出する算出手段と、該算出手段により算出された前記
検出領域の異なる位置におけるそれぞれの差情報より撮
影画面内での被写体の位置を判定する判定手段と、該判
定手段にて判定された被写体の位置に前記測光領域を設
定する測光領域追尾手段と、被写体の位置に設定された
前記測光領域、それ以外の領域或は測光領域を含む全領
域での露光情報をそれぞれ検出する露光検出手段と、前
記測光領域とそれ以外の領域、或は測光領域と該測光領
域を含む全領域にて得られる映像信号中の所定の周波数
成分の差情報を算出し、この差情報に基づいて前記露光
検出手段よりのそれぞれの出力に重み付けする重み付け
手段と、該重み付け手段により出力されるそれぞれの演
算値をもって露光制御を行う露光制御手段とを設けたこ
とを特徴とする自動露光制御装置。(1) In an automatic exposure control device having a photometric area within the screen, a calculation means for calculating difference information of predetermined frequency components in video signals obtained inside and outside a movable detection area within the screen, and the calculation means determining means for determining the position of the subject within the photographic screen from difference information at different positions of the detection area calculated by the means; and setting the photometric area at the position of the subject determined by the determining means. photometric area tracking means; exposure detection means for detecting exposure information in the photometric area set at the position of the subject, other areas, or all areas including the photometric area; and the photometric area and other areas. , or calculating difference information between a predetermined frequency component in a video signal obtained in a photometric area and the entire area including the photometric area, and weighting each output from the exposure detection means based on this difference information. An automatic exposure control device comprising: weighting means; and exposure control means for controlling exposure using respective calculated values output by the weighting means.
する特許請求の範囲第１項記載の自動露光制御装置。(2) The automatic exposure control device according to claim 1, wherein the predetermined frequency component is a luminance component in a video signal.
高域側の高周波成分とする特許請求の範囲第１項記載の
自動露光制御装置。(3) The automatic exposure control device according to claim 1, wherein the predetermined frequency component is a high frequency component on the high frequency side of the luminance component in the video signal.
Priority Applications (3)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP62277384A JP2631217B2 (en) | 1987-11-04 | 1987-11-04 | Automatic exposure control device |
| US07/582,798 US5272538A (en) | 1987-11-04 | 1990-09-13 | Exposure control device |
| US08/278,645 US6124891A (en) | 1987-11-04 | 1994-07-21 | Exposure control device |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP62277384A JP2631217B2 (en) | 1987-11-04 | 1987-11-04 | Automatic exposure control device |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPH01120180A true JPH01120180A (en) | 1989-05-12 |
| JP2631217B2 JP2631217B2 (en) | 1997-07-16 |
Family
ID=17582777
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP62277384A Expired - Fee Related JP2631217B2 (en) | 1987-11-04 | 1987-11-04 | Automatic exposure control device |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JP2631217B2 (en) |
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| WO2012014678A1 (en) * | 2010-07-26 | 2012-02-02 | オリンパスメディカルシステムズ株式会社 | Endoscope device and method for controlling endoscope device |
| JP2015050748A (en) * | 2013-09-04 | 2015-03-16 | 株式会社ニコン | Imaging device |
-
1987
- 1987-11-04 JP JP62277384A patent/JP2631217B2/en not_active Expired - Fee Related
Cited By (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| WO2012014678A1 (en) * | 2010-07-26 | 2012-02-02 | オリンパスメディカルシステムズ株式会社 | Endoscope device and method for controlling endoscope device |
| JP5132841B2 (en) * | 2010-07-26 | 2013-01-30 | オリンパスメディカルシステムズ株式会社 | Endoscope apparatus and control method of endoscope apparatus |
| CN102970916A (en) * | 2010-07-26 | 2013-03-13 | 奥林巴斯医疗株式会社 | Endoscope device and method for controlling endoscope device |
| US8477182B2 (en) | 2010-07-26 | 2013-07-02 | Olympus Medical Systems Corp. | Endoscope apparatus and control method of endoscope apparatus |
| JP2015050748A (en) * | 2013-09-04 | 2015-03-16 | 株式会社ニコン | Imaging device |
Also Published As
| Publication number | Publication date |
|---|---|
| JP2631217B2 (en) | 1997-07-16 |
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Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| LAPS | Cancellation because of no payment of annual fees |