JPS5927894B2 - Out of focus image detection method - Google Patents
Out of focus image detection methodInfo
- Publication number
- JPS5927894B2 JPS5927894B2 JP3984180A JP3984180A JPS5927894B2 JP S5927894 B2 JPS5927894 B2 JP S5927894B2 JP 3984180 A JP3984180 A JP 3984180A JP 3984180 A JP3984180 A JP 3984180A JP S5927894 B2 JPS5927894 B2 JP S5927894B2
- Authority
- JP
- Japan
- Prior art keywords
- difference
- transmittance
- frequency
- focus image
- frequency distribution
- 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.)
- Expired
Links
Classifications
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B27—WORKING OR PRESERVING WOOD OR SIMILAR MATERIAL; NAILING OR STAPLING MACHINES IN GENERAL
- B27B—SAWS FOR WOOD OR SIMILAR MATERIAL; COMPONENTS OR ACCESSORIES THEREFOR
- B27B17/00—Chain saws; Equipment therefor
- B27B17/0008—Means for carrying the chain saw, e.g. handles
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B27—WORKING OR PRESERVING WOOD OR SIMILAR MATERIAL; NAILING OR STAPLING MACHINES IN GENERAL
- B27B—SAWS FOR WOOD OR SIMILAR MATERIAL; COMPONENTS OR ACCESSORIES THEREFOR
- B27B17/00—Chain saws; Equipment therefor
- B27B17/02—Chain saws equipped with guide bar
-
- G—PHYSICS
- G03—PHOTOGRAPHY; CINEMATOGRAPHY; ANALOGOUS TECHNIQUES USING WAVES OTHER THAN OPTICAL WAVES; ELECTROGRAPHY; HOLOGRAPHY
- G03B—APPARATUS OR ARRANGEMENTS FOR TAKING PHOTOGRAPHS OR FOR PROJECTING OR VIEWING THEM; APPARATUS OR ARRANGEMENTS EMPLOYING ANALOGOUS TECHNIQUES USING WAVES OTHER THAN OPTICAL WAVES; ACCESSORIES THEREFOR
- G03B27/00—Photographic printing apparatus
- G03B27/72—Controlling or varying light intensity, spectral composition, or exposure time in photographic printing apparatus
Landscapes
- Life Sciences & Earth Sciences (AREA)
- Engineering & Computer Science (AREA)
- Mechanical Engineering (AREA)
- Wood Science & Technology (AREA)
- Forests & Forestry (AREA)
- Physics & Mathematics (AREA)
- Spectroscopy & Molecular Physics (AREA)
- General Physics & Mathematics (AREA)
- Control Of Exposure In Printing And Copying (AREA)
- Facsimile Image Signal Circuits (AREA)
- Photometry And Measurement Of Optical Pulse Characteristics (AREA)
Description
【発明の詳細な説明】
本発明は写真フィルム上に記録されている画像がピンボ
ケ画像であるかどうかを検査する方法に関するものであ
る。DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for inspecting whether an image recorded on a photographic film is out of focus.
アマチュアの写真フィルムの焼付けに際しては、露出が
不適正であつて補正を行なうことができないものと、焦
点調節が不適当なために画像がボケているもの(これを
「ピンボケ画像」という。When printing photographic film by amateurs, there are cases where the exposure is inappropriate and cannot be corrected, and images that are out of focus due to inappropriate focus adjustment (these are called ``out-of-focus images'').
)とを取り除く必要がある。ピンボケ画像の検出方法と
しては従来から種々の方法が提案されている。) and need to be removed. Various methods have been proposed for detecting out-of-focus images.
その一つとして、画像のフーリエ変換を用いてそのスペ
クトル成分が予め定めた周波数領域以下かどうかを調べ
て、それにより画像のボケを判別する方法がある。この
方法において光学的なフーリエ変換を行なう場合には精
度が高くかつ複雑で高価なシステムが必要になる。また
電気的にフーリエ変換を行なう場合は、通常の写真プリ
ンタのプリント速度に合う高速のフーリエ変換素子が存
在していない等の難点がある。別の方法としては、写真
フィルムを線状に走査し、高帯域幅での最大濃度勾配と
、高い空間周波数領域を取り除くことにより不鮮明にさ
れた画像内容の最大濃度勾配とを求め、これらの2つの
濃度勾配の商を算出し、この商が閾値よりも大きいかど
うかによつて画像のボケを検出する方法(特開昭53−
70428号)等がある。One method is to use Fourier transform of an image to check whether its spectral components are below a predetermined frequency range, thereby determining whether the image is blurred. Performing an optical Fourier transform in this method requires a highly accurate, complex, and expensive system. Further, when Fourier transform is performed electrically, there are drawbacks such as the absence of high-speed Fourier transform elements that match the printing speed of ordinary photographic printers. Another method is to linearly scan the photographic film, find the maximum density gradient in the high bandwidth, and the maximum density gradient in the image content that has been blurred by removing high spatial frequency regions, and calculate these two. A method of calculating the quotient of two density gradients and detecting blur in an image based on whether this quotient is larger than a threshold
70428) etc.
この濃度勾配を用いる方法では、最大値を検出する回路
と、2つの濃度勾配の商を求める回路とが必要となるた
め、装置が複雑になるという欠点がある。本発明は上記
欠点を解決するもので、ピンボケ画像の検出を簡単に行
なうことができるようにした方法を提供することを目的
とするものである。本発明は、写真フィルムの画像面を
測定面積の異なる2つの測光系を用いて走査・測定し、
得られた2種類の透過率または透過濃度の値の差を求め
、この差の度数分布の特性から、ピンボケ画像の判定を
行なうようにしたことを特徴とするものである。撮影レ
刀のピント(FOcus)は、主要被写体が鮮明に記録
されるように調節されるのが一般的である。This method using concentration gradients requires a circuit for detecting the maximum value and a circuit for calculating the quotient of two concentration gradients, which has the disadvantage of complicating the apparatus. SUMMARY OF THE INVENTION The present invention aims to solve the above-mentioned drawbacks, and provides a method that allows easy detection of out-of-focus images. The present invention scans and measures the image plane of a photographic film using two photometric systems with different measurement areas,
The present invention is characterized in that the difference between the two types of transmittance or transmission density values obtained is determined, and an out-of-focus image is determined based on the characteristics of the frequency distribution of this difference. The focus of the camera is generally adjusted so that the main subject is clearly recorded.
そして、主要被写体は画面の中央に位置していることが
経験的に知られているから、アマチュアの写真フィルム
では、画面の中央部を走査してピンボケ画像の検出を行
なうのが望ましい。以下、図面を参照して本発明につい
て詳細に説明する。第1図は鮮明な画像の濃度測定を示
すものである。Since it is known from experience that the main subject is located at the center of the screen, in amateur photographic films it is desirable to scan the center of the screen to detect out-of-focus images. Hereinafter, the present invention will be explained in detail with reference to the drawings. FIG. 1 shows the density measurement of a clear image.
鮮明な画像のエッジ像は濃度変化が大きいからAのよう
な濃度勾配になつている。そこでこのオリジナル画像を
測定面積の異なる2つの測光系を用いて走査・測定すれ
ば、測定面積の小さい測光系を用いて測定した濃度はB
のようになり、大きい測定面積の測光系を用いて測定し
た濃度はCのように勾配がゆるやかな曲線となる。測光
系の測定面積としては、一例として一方がオリジナル面
像土で0.1mm角のもの、他方は17!Em角のもの
が用いられる。したがつて、0.1mm角のものは20
C/Mmの周波数をもつた画像まで検出することが可能
であり、1mm角のものでは2C/Mmの周波数まで検
出することができる。このように測定面積の異なつた測
光系を用いて測定した濃度の差を求めればDのような曲
線が得られる。Since the edge image of a clear image has a large density change, it has a density gradient as shown in A. Therefore, if this original image is scanned and measured using two photometric systems with different measurement areas, the density measured using the photometric system with a smaller measurement area will be B.
The density measured using a photometric system with a large measurement area becomes a curve with a gentle slope like C. As an example, one of the measurement areas of the photometric system is an original surface image of 0.1 mm square, and the other is 17! Em angle ones are used. Therefore, 0.1 mm square is 20
It is possible to detect images up to a frequency of C/Mm, and for a 1 mm square image, up to a frequency of 2C/Mm can be detected. If the difference in density measured using photometric systems with different measurement areas is determined in this way, a curve like D can be obtained.
一般に鮮明な画像では、2つの測定濃度の差が大きいの
で、曲線の振幅が大きな値になつている。この濃度差を
サンプリングして所望の濃度幅毎に区分した領域に存在
している個数を調べて、濃度差を横軸にとり、個数を縦
軸にとつた度数分布曲線を描けば、第3図の実線1に示
すような曲線となる。Generally, in a clear image, the difference between two measured densities is large, so the amplitude of the curve is a large value. If we sample this density difference and find out the number of particles existing in areas divided into desired density widths, we can draw a frequency distribution curve with the density difference on the horizontal axis and the number on the vertical axis, as shown in Figure 3. A curve as shown in solid line 1 is obtained.
第2図はピンボケ画像の測定を示すものである。FIG. 2 shows the measurement of an out-of-focus image.
ピンボケ画像はそのエッジ部分では濃度変化がゆるやか
であるからAのようになつている。このエッジ画像を測
定面積の異る2つの測光系を用いて測定すれば、B,C
のような濃度曲線が得られる。この2つの測定濃度はと
もにゆるやかな曲線となつているから、その差が小さく
Dのような曲線となる。この測定濃度の差をサンプリン
グして度数分布曲線を作れば、第3図の点線2に示すよ
うになる。第3図から分るように、鮮明な画像とピンボ
ケ画像とでは、度数分布曲線の形状に顕著な差異がある
。The out-of-focus image looks like A because the density changes slowly at its edge portions. If this edge image is measured using two photometric systems with different measurement areas, B and C
A concentration curve like this is obtained. Since both of these two measured densities form gentle curves, the difference between them is small, resulting in a curve like D. If this difference in measured concentration is sampled to create a frequency distribution curve, it will be as shown by dotted line 2 in FIG. As can be seen from FIG. 3, there is a significant difference in the shape of the frequency distribution curve between a clear image and an out-of-focus image.
したがつてこの差異が明確になる特性値を用いれば、こ
の特性値からピンボケ画像を検知することができる。こ
の特性値としては濃度差△Dが一定領域例えば−0.1
5≦△D≦0.15に存在している累積度数と、△D≦
−0.15及び△D≧0.15に存在している累積度数
の比または差を用いることができる。Therefore, if a characteristic value that makes this difference clear is used, an out-of-focus image can be detected from this characteristic value. As for this characteristic value, the density difference ΔD is constant, for example, −0.1
The cumulative frequency existing in 5≦△D≦0.15 and △D≦
A ratio or difference in cumulative frequencies that exists between −0.15 and ΔD≧0.15 can be used.
この場合、上記比または差の値が閾値以内にあるかどう
かによつてピンボケ画像の判定を行なう。あるいは所望
の濃度差の点における度数を用いることもできる。さら
には特性値として前記度数分布曲線のピーク値、あるい
は該ピーク値とある濃度差の点における度数との比、ま
たはある領域内における前記曲線下の面積等を用いるこ
とができる。第4図は本発明を実施する装置を示すもの
である。In this case, an out-of-focus image is determined based on whether the ratio or difference value is within a threshold value. Alternatively, the frequency at the point of the desired density difference may be used. Further, as the characteristic value, the peak value of the frequency distribution curve, the ratio of the peak value to the frequency at a certain density difference point, or the area under the curve within a certain region can be used. FIG. 4 shows an apparatus for carrying out the invention.
光源3から放出された光は、コンデンサレンズ4を通り
、矢線方向に移動する写真フィルム5に到達する。この
写真フィルム5上には画像が記録されており、光源3か
らの光によつて照明される。写真フィルム5を透過した
光は、ハーフミラー6により透過光と反射光とに2分割
される。Light emitted from the light source 3 passes through a condenser lens 4 and reaches a photographic film 5 moving in the direction of the arrow. An image is recorded on the photographic film 5, and is illuminated by light from the light source 3. The light transmitted through the photographic film 5 is divided by a half mirror 6 into transmitted light and reflected light.
・・ーフミラー6を透過した光は、レンズ7、ミラー8
、スリット9を経て光電子増倍管10に入射し、電気信
号に変換される。前記レンズ7はスリット9の開口を写
真フィルム5上に結像させるように配置されている。...The light transmitted through the mirror 6 passes through the lens 7 and the mirror 8.
, enters the photomultiplier tube 10 through the slit 9, and is converted into an electrical signal. The lens 7 is arranged so as to form an image of the opening of the slit 9 on the photographic film 5.
一方、ハーフミラー6で反射された光はレンズ11.ス
リット12を通り、光電子増倍管13に入射する。この
スリット12は、前記スリット9よりもその開口が大き
くなつている。例えばスリット9の開口を1mm角、ス
リット12の開口を10mm角とし、レンズ7,11の
倍率を1/10とすれば、写真フィルム5上での測定面
積はそれぞれ0.1mm角と1mm角となる。前記光電
子増倍管10,13の出力信号は、濃度値で演算する場
合には対数変換回路を経て、また透過率で演算する場合
はそのまま差動増幅器14に送られ、ここで両信号の差
が算出される。On the other hand, the light reflected by the half mirror 6 is transmitted through the lens 11. The light passes through the slit 12 and enters the photomultiplier tube 13 . This slit 12 has a larger opening than the slit 9. For example, if the opening of the slit 9 is 1 mm square, the opening of the slit 12 is 10 mm square, and the magnification of the lenses 7 and 11 is 1/10, the measured areas on the photographic film 5 will be 0.1 mm square and 1 mm square, respectively. Become. The output signals of the photomultiplier tubes 10 and 13 are sent through a logarithmic conversion circuit when calculating the concentration value, or are sent as they are to the differential amplifier 14 when calculating the transmittance, where the difference between the two signals is calculated. is calculated.
この差動増幅器14の出力信号は、ある適当な幅ごとに
寄せ集めて積算して度数分布を算出する回路15に入力
される。積算回路16は−0.15≦△D≦0.15内
にあるものを積算し、積算回路17は△D〈−0.15
および0.15〈△Dにあるものを積算する。The output signal of the differential amplifier 14 is inputted to a circuit 15 which collects the signals at a certain appropriate width and integrates them to calculate a frequency distribution. The integration circuit 16 integrates the values within -0.15≦△D≦0.15, and the integration circuit 17 integrates △D<-0.15.
and 0.15〈ΔD are integrated.
この領域分割されて積算された累積度数は比較回路18
に送られ、ここでその比が算出され、かつその比が一定
値kよりも大きいかどうかについて判定される。そして
前記の比が一定値kよりも大きいときには、鮮明画像で
あることを示す信号が出力され、小さいときにはピンボ
ケ画像であることを示す信号が出力される。上記構成を
有する本発明によれば、測定面積の異なる2つの測光系
を用いて画像の濃度を測定し、得られた2つの測定濃度
の差を求め、この濃度差の度数分布からピンボケ画像を
検出するものであるから、簡単な装置で、かつ容易にピ
ンボケ画像を検出することができる。The cumulative frequency accumulated by dividing the area is calculated by the comparator circuit 18.
, where the ratio is calculated and it is determined whether the ratio is greater than a constant value k. When the ratio is larger than a certain value k, a signal indicating that the image is clear is output, and when it is smaller, a signal indicating that the image is out of focus is output. According to the present invention having the above configuration, the density of an image is measured using two photometric systems having different measurement areas, the difference between the two obtained measured densities is determined, and an out-of-focus image is determined from the frequency distribution of this density difference. Since it is a detection method, it is possible to easily detect out-of-focus images with a simple device.
第1図は鮮明画像と、その測定濃度および測定濃度の差
を示すグラフ、第2図はピンボケ画像を示す第1図と同
様なグラフ、第3図は鮮明画像とピンボケ画像の度数分
布曲線を示す図、第4図は本発明を実施する装置の概略
図である。
1・・・・・・鮮明画像の度数分布曲線、2・・・・・
・ピンボケ画像の度数分布曲線、5・・・・・・写真フ
ィルム、9,12・・・・・・スリット、10,13・
・・・・・光電子増倍管、14・・・・・・差動増幅器
、15・・・・・・演算回路、16,17・・・・・・
積算回路、18・・・・・・比較回路。Figure 1 is a graph showing a clear image, its measured density, and the difference between the measured densities, Figure 2 is a graph similar to Figure 1 showing an out-of-focus image, and Figure 3 is a graph showing the frequency distribution curve of a clear image and an out-of-focus image. The figure shown, FIG. 4, is a schematic diagram of an apparatus for carrying out the present invention. 1... Frequency distribution curve of clear image, 2...
・Frequency distribution curve of out-of-focus image, 5... Photographic film, 9, 12... Slit, 10, 13.
...Photomultiplier tube, 14...Differential amplifier, 15...Arithmetic circuit, 16,17...
Integration circuit, 18... Comparison circuit.
Claims (1)
率または透過濃度を、測定面積が異なつた2つの測光系
を用いて測定し、得られた2種類の透過率または透過濃
度値の差を求め、この差の度数分布の特性からピンボケ
画像を検出するようにしたことを特徴とするピンボケ画
像検出方法。 2 前記度数分布の特性が、前記透過率または透過濃度
値の差が一定領域に存在している累積度数と、前記一定
領域外に存在している累積度数の比であることを特徴と
する特許請求の範囲第1項記載のピンボケ画像検出方法
。 3 前記度数分布の特性が、前記透過率または透過濃度
値の差が一定領域に存在している累積度数と、前記一定
領域外に存在している累積度数の差であることを特徴と
する特許請求の範囲第1項記載のピンボケ画像検出方法
。 4 前記度数分布の特性が、前記透過率または透過濃度
値の差が一定の値である点における度数の値であること
を特徴とする特許請求の範囲第1項記載のピンボケ画像
検出方法。 5 前記度数分布の特性が、度数分布曲線のピーク値、
あるいは該ピーク値と前記透過率または透過濃度値の差
が一定の値である点における度数との比であることを特
徴とする特許請求の範囲第1項記載のピンボケ画像検出
方法。 6 前記度数分布の特性が度数分布曲線のピーク値と前
記透過率または透過濃度値の差が一定の値である点にお
ける度数との差であることを特徴とする特許請求の範囲
第1項記載のピンボケ画像検出方法。[Claims] 1. The transmittance or transmittance density of each part of an image recorded on a photographic film is measured using two photometric systems with different measurement areas, and the two types of transmittance or A method for detecting an out-of-focus image, characterized in that a difference in transmission density values is determined, and an out-of-focus image is detected from the characteristics of the frequency distribution of this difference. 2. A patent characterized in that the characteristic of the frequency distribution is the ratio of the cumulative frequency in which the difference in transmittance or transmission density value exists in a certain area to the cumulative frequency in which the difference in the transmittance or transmission density value exists outside the certain area. An out-of-focus image detection method according to claim 1. 3. A patent characterized in that the characteristic of the frequency distribution is the difference in the transmittance or transmission density value between a cumulative frequency existing in a certain area and a cumulative frequency existing outside the certain area. An out-of-focus image detection method according to claim 1. 4. The out-of-focus image detection method according to claim 1, wherein the characteristic of the frequency distribution is a frequency value at a point where the difference between the transmittance or the transmission density value is a constant value. 5 The characteristic of the frequency distribution is a peak value of a frequency distribution curve,
Alternatively, the method for detecting an out-of-focus image according to claim 1 is a ratio between the peak value and the frequency at a point where the difference between the transmittance or the transmittance density value is a constant value. 6. Claim 1, wherein the characteristic of the frequency distribution is the difference between the peak value of the frequency distribution curve and the frequency at a point where the difference between the transmittance or the transmission density value is a constant value. out-of-focus image detection method.
Priority Applications (3)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
JP3984180A JPS5927894B2 (en) | 1980-03-28 | 1980-03-28 | Out of focus image detection method |
DE19813111968 DE3111968C2 (en) | 1980-03-28 | 1981-03-26 | Device for detecting a blurred photographic image |
CH210781A CH651141A5 (en) | 1980-03-28 | 1981-03-27 | METHOD FOR DETECTING THE BLURRIES OF A PHOTOGRAPHIC IMAGE. |
Applications Claiming Priority (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
JP3984180A JPS5927894B2 (en) | 1980-03-28 | 1980-03-28 | Out of focus image detection method |
Publications (2)
Publication Number | Publication Date |
---|---|
JPS56137341A JPS56137341A (en) | 1981-10-27 |
JPS5927894B2 true JPS5927894B2 (en) | 1984-07-09 |
Family
ID=12564182
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
JP3984180A Expired JPS5927894B2 (en) | 1980-03-28 | 1980-03-28 | Out of focus image detection method |
Country Status (3)
Country | Link |
---|---|
JP (1) | JPS5927894B2 (en) |
CH (1) | CH651141A5 (en) |
DE (1) | DE3111968C2 (en) |
Families Citing this family (4)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JPS5710132A (en) * | 1980-06-20 | 1982-01-19 | Fuji Photo Film Co Ltd | Detecting method for out-of-focus picture |
JPS5987447A (en) * | 1982-11-11 | 1984-05-21 | Fuji Photo Film Co Ltd | Photographic printing method |
JPS60207131A (en) * | 1984-03-30 | 1985-10-18 | Fuji Photo Film Co Ltd | Detecting method of negative frame not to be printed |
DE3519236C2 (en) * | 1984-06-01 | 1995-11-02 | Fuji Photo Film Co Ltd | Automatic notching device for the preparation of moving photographic document strips |
Family Cites Families (2)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
DE2244340C2 (en) * | 1972-09-09 | 1986-02-06 | Agfa-Gevaert Ag, 5090 Leverkusen | Method and device for the preliminary examination of master copies |
DE2654943C2 (en) * | 1976-12-03 | 1985-10-24 | Agfa-Gevaert Ag, 5090 Leverkusen | Method and device for the preliminary examination of master copies combined to form a master tape |
-
1980
- 1980-03-28 JP JP3984180A patent/JPS5927894B2/en not_active Expired
-
1981
- 1981-03-26 DE DE19813111968 patent/DE3111968C2/en not_active Expired
- 1981-03-27 CH CH210781A patent/CH651141A5/en not_active IP Right Cessation
Also Published As
Publication number | Publication date |
---|---|
CH651141A5 (en) | 1985-08-30 |
DE3111968C2 (en) | 1991-07-11 |
DE3111968A1 (en) | 1982-01-07 |
JPS56137341A (en) | 1981-10-27 |
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