EP1829362A1 - Procede de codage d'image, et dispositif de codage d'image - Google Patents

Procede de codage d'image, et dispositif de codage d'image

Info

Publication number
EP1829362A1
EP1829362A1 EP05850486A EP05850486A EP1829362A1 EP 1829362 A1 EP1829362 A1 EP 1829362A1 EP 05850486 A EP05850486 A EP 05850486A EP 05850486 A EP05850486 A EP 05850486A EP 1829362 A1 EP1829362 A1 EP 1829362A1
Authority
EP
European Patent Office
Prior art keywords
image
flashed
brightness
uob
color
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.)
Withdrawn
Application number
EP05850486A
Other languages
German (de)
English (en)
Inventor
Robert Kutka
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Aumovio Germany GmbH
Original Assignee
Siemens AG
Siemens Corp
Priority date (The priority date 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 date listed.)
Filing date
Publication date
Application filed by Siemens AG, Siemens Corp filed Critical Siemens AG
Publication of EP1829362A1 publication Critical patent/EP1829362A1/fr
Withdrawn legal-status Critical Current

Links

Classifications

    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04N—PICTORIAL COMMUNICATION, e.g. TELEVISION
    • H04N23/00—Cameras or camera modules comprising electronic image sensors; Control thereof
    • H04N23/70—Circuitry for compensating brightness variation in the scene
    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04N—PICTORIAL COMMUNICATION, e.g. TELEVISION
    • H04N23/00—Cameras or camera modules comprising electronic image sensors; Control thereof
    • H04N23/70—Circuitry for compensating brightness variation in the scene
    • H04N23/74—Circuitry for compensating brightness variation in the scene by influencing the scene brightness using illuminating means
    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04N—PICTORIAL COMMUNICATION, e.g. TELEVISION
    • H04N23/00—Cameras or camera modules comprising electronic image sensors; Control thereof
    • H04N23/70—Circuitry for compensating brightness variation in the scene
    • H04N23/741—Circuitry for compensating brightness variation in the scene by increasing the dynamic range of the image compared to the dynamic range of the electronic image sensors

Definitions

  • the invention relates to an image coding method according to the preamble of claim 1 and an image coding apparatus according to the preamble of claim 8.
  • Photographic equipment has been a mass-produced product for many years.
  • the mass market of photography has also been revitalized.
  • a variety of digital cameras have been offered on the market.
  • a possibility for taking photographs has been offered for some time in mobile devices.
  • multimedia messaging service MMS
  • a user can transmit photographs in a simple and quick way.
  • a common way to take photographs in dark conditions is to use a flash.
  • the image object to be recorded such as a person
  • stands at ren portable pe ⁇ devices usually only a flash device for Verhe- supply.
  • Such a flash unit achieves average picture quality for picture objects located at a certain distance from the flash unit.
  • Image objects that are too close to the flash unit too bright and image objects that are too far from the flash, only darkly recorded.
  • the terms image, photo and photography are used interchangeably.
  • the object of the present invention is to provide a picture coding method or picture coding apparatus which achieves a good picture quality even when using a flash light for taking photographs.
  • the picture coding method with at least one ungeblitzten picture and at least one flashed image of the same subject are of at least one ungeblitzten receiving a ungeblitztes image and at least one flashed Recordin ⁇ me a Flashed image is formed, wherein at least one of the images of at least one brightness or color adjustment to enlarge is subjected to a respective contrast extent, and generates a result representation from a combination of the flashed and the non-flashed image.
  • the method according to the invention it is possible to generate from at least one flashed and at least one non-flashed image a result representation which has an improved image quality than one of the non-flashed images.
  • the respective contrast range is increased by the brightness or color adjustment in such a way that brightness or color differences, which are low in one of the images, become more evident in the representation of the result.
  • the combination of the non-flashed and the flashed image ensures that in the flashed image too bright image areas, such as a too bright image object In the foreground of the image, darker and darker image areas, such as a background image, be lightened. Furthermore, the combination reduces disturbing image noise.
  • the brightness or color adjustment of a brightness or color distribution of at least one image is carried out with the aid of a linear spread. Due to the linear spread, an enlargement of the contrast range is achieved with a low processing complexity.
  • the color adjustment of a color distribution of at least one receiving ⁇ performed such that a color value of a pixel with that Sp Drownfak ⁇ tor is spread, which is used for brightness adjustment on this point.
  • the color adjustment is at least one pixel in dependence on the determined Hellig ⁇ keitsanpassung same pixel.
  • On acceptance such as. The flashed recording, various variants of the brightness or color adjustment applied to advertising.
  • the non-slit image is determined by superimposing a plurality of non-flashed images and / or the flashed image by superimposing multiple flashed images. Due to the superposition of several images, an image noise can be reduced and resulted in an increase of the image quality ⁇ ty be achieved. If, before the superimposition of each of the motion compensation ungeblitzten or flashed recordings performed such artifacts can be reduced within the ungeblitzten or flashed image and characterized in addition, it will höht ⁇ image quality.
  • the flashed and / or non-flashed image can be rendered qualitatively by at least one image enhancement method, in particular by noise suppression.
  • Noise reduction by means of a low-SUC ⁇ gen. This is aimed to further increase the image quality, it ⁇ .
  • the combination is implemented of the flashed and the un ⁇ flashed image with a weighted addition. This ensures a simple and efficient realization of the combination of the flashed and the non-flashed image.
  • the invention relates to the image coding apparatus for carrying out an image coding method with at least one non-flashed image and at least one flashed image of the same subject, with a first means for producing an unflashed image from at least one non-flashed image
  • the picture coding apparatus enables execution of the picture coding method according to the present invention.
  • FIG. 1 shows a mobile radio device which comprises a picture coding device for carrying out the picture coding method according to the invention
  • FIG. 2 shows a flow chart for carrying out the picture coding method according to the invention
  • FIG. 3 shows images of several images using the image coding method according to the invention.
  • Figure 7 is a generation of the image from a ungeblitzten ungeblitzten recording, wherein the color value of the associated brightness value of this image is modified point of a pixel in dependence of the keitsanpassung by the Hellig ⁇ determined respective spreading factor ⁇ ;
  • FIG. 8 shows a flow chart for the partial implementation of the image coding method according to the invention, wherein a corrected non-flashed image is determined from a plurality of non-flashed images using motion compensation; Elements with the same function and effect are provided with the same reference numerals.
  • a mobile radio device MG can be used, which has a camera K, a flash unit BZ and a Schmcodiervor ⁇ device BV, wherein the image coding BV realizes the image coding method according to the invention.
  • FIG. 1 shows such a mobile radio device MG.
  • This mobile radio device MG ⁇ supported eg. The GSM standard (GSM-Global System for Mobile Communication).
  • GSM-Global System for Mobile Communication GSM-Global System for Mobile Communication
  • a Mobilfunkge ⁇ Raets MG picture coding method according to the invention can be processed in a digital camera or a camera, the analog images, implemented and realized.
  • the individual processing steps of the method according to the invention are shown in FIG. 2 and will be explained in more detail below.
  • the mobile radio device MG initially generates an unblitzed recording UOB and a flashed picture GOB of the same subject.
  • an unblitzed recording UOB and a flashed picture GOB of the same subject For Errei ⁇ chen a very good result of the picture coding method according to the invention, it is expedient in practice that both the ungeblitzte and the flashed recording UOB or GOB show the same motif.
  • the term "same subject” is to be understood that image objects in these two shots in their position not at all or only slightly change. Both brightness and color differences of the different shots can occur with the same subject.
  • the MG unge ⁇ and flashed recording UOB or GOB are generated within ei ⁇ nes short time interval, such as., Within 30 ms. Through this very short recording time at ⁇ the record is achieved that the recorded subject DAS same is.
  • ei ⁇ nes short time interval such as., Within 30 ms.
  • genes can ⁇ are sequentially numbered in an alternative extension of the method several ungeblitzte or flashed recordings UOB, GOB. This will be discussed later.
  • a picture such as a flashed picture GOB, comprises a plurality of picture elements BP.
  • a pixel BP can be represented by one or more components, insbesonde ⁇ re by the color components of red / green / blue (R / G / B) or by a luminance component Y and two color components U, V.
  • an image point BP be written as BP (R, G, B) or BP (Y, U, V).
  • the characteristic of the non-flashed or flashed recording UOB or GOB will be explained in more detail with reference to FIG.
  • the part 4a shows a ungeblitzte recording UOB, has been included in the egg ⁇ ne person. Use the transverse lines in part of Figure 4a, it is indicated that the whole ungeblitzte on ⁇ acquisition UOB has only dark image areas. Another non-slit UOB recording can be seen in part 3a.
  • An analysis of the distribution of brightness values within the un ⁇ flashed recording UOB can be made using a brightness histogram ⁇ .
  • Partial figure 4b records such a brightness histogram.
  • Sub-figure 4b the unblinded image comprises UOB the subfigure 4a mainly image locations and and predominantly dark brightness values W.
  • part ⁇ figure 4c a Flashed recording GOB is, which is characterized in that the person's face captured light, the background whereas opposite the captured person is dark. This fact is reflected in the grasperiei ⁇ gen brightness histogram in part 4d in each case both for dark and for bright brightness values W of the brightness histogram, a brightness maximum advantage exis ⁇ .
  • the brightness shown in the partial Figures 4b and 4d keitshistogramme are only one possible execution ⁇ represents example and may come to light in other flashed or un- flashed shots in a modified form.
  • At least one of the images UOB, GOB is subjected to at least one brightness or color adaptation HA, FA for enlarging the respective contrast range.
  • a flashed and / or a non-flashed shot GOB, UOB can be adjusted. Further, this adjustment can be made for the brightness or color as well as for the brightness and the color of a picture.
  • magnification of each ⁇ ilia contrast range is illustrated by the brightness adjustment HA.
  • the brightness histogram of ⁇ is part 4b shown. This reveals that the vast number of pixels of the recording ungeblitzten UOB are dark pixels and the ungeblitzte on ⁇ acquisition UOB has no bright pixels.
  • the distribution of the brightness values W within the brightness is now intensity histogram linearly spread.
  • the result of this linea ⁇ ren spread is seen in part 5b.
  • Such brightness correction is ⁇ example, from [1] page 178-179 known, there being the spreading is referred to as variation in dot gain.
  • the spread is used to increase the contrast range of the brightness values.
  • the sectionfi ⁇ gur 6a outputs the brightness histogram of a GOB flashed receiving part according to figure 4d again.
  • the flashed recording GOB has a large number of dark and very bright pixels, whereby there are hardly any pixels in the middle brightness range.
  • Gradation curves are known, for example, from [1] pages 140 to 143.
  • the Grada ⁇ tion curve GK according to partial figure 6b, for example, formed such that summed over the range of values W, from 0 to 255 or from black to white, the probability of occurrence of the brightness values A (W) and will bear on the ordinate up ⁇ .
  • the original value range W is now spread and a new modified value range W 1 is created .
  • the modified value range W 1 includes, for example, a range of values from "0" to "255".
  • a modified brightness value W is formed from a spreading factor F and the brightness value W. This can be described by the following equation:
  • the respective pictures UOB, GOB are subjected at least to the brightness or color adaptation HA, FA.
  • the first means M1 produces an unlit image UB and the second means M2 produces a flashed image GB.
  • Both the non-flashed and the flashed image UB, GB have a significantly improved contrast range than the original non-flashed images UOB, GOB.
  • a color match FA can be performed.
  • the color matching FA can be performed as a function of the brightness adjustment HA become. This is shown graphically in FIG. Example ⁇ , a pixel includes a luminance component Y and two color components U, V. First, the luminance component Y is calculated using the procedure described above egg ner brightness adjustment HA subjected. This results in a modified brightness component Y 1 which can be described by the following equation:
  • F describes that spreading factor which was used in the spreading of the brightness value Y into the associated modified brightness value Y 1 .
  • the Sp Drak ⁇ tor F can change depending on the brightness value Y.
  • the color component U is subsequently subjected, as a function of the brightness adjustment HA, to a color adaptation FA as follows:
  • the spread of the color component U is directly dependent on the spreading factor F, which was used in the brightness adjustment HA.
  • the reference U 1 represents a modified color value after the spread. Describes for example the color component U a differential Farbkom ⁇ component whereby, for example, the value 127 through 255 represents the color in the zero point value range of 0, the modifi ed ⁇ color value U 1 can be determined as follows:
  • the brightness or color values are defined by decimal numbers within a predetermined value range, such as from 0 to 255. This value range indicates the brightness or color resolution. In this example, 265 different Hellig ⁇ keits- or color values can be reproduced.
  • the erfindungsge ⁇ Permitted picture coding method is not limited to a particular range of values, such as 0 to 256, but may, for any range of values, such as 0 can be used to 1024 or -500 to +500.
  • a third means M3 is a perennial flowering plant from a combination of flashed and un- flashed image GB, UB is generated.
  • This combination is performed with a weighted addition of the flashed and unflattered images GB, UB.
  • a non ⁇ linear combination such as, the addition of the squared values of the image and the values of the ungeblitzten flashed image.
  • the combination is not limited to one of the examples mentioned.
  • Y E (i, j) a * Y UB (i, j) + b * Y GB (i, j)
  • (i, j) is a two-dimensional position ei ⁇ nes pixel BP within an image or depicting ⁇ lung, Y UB a brightness component of the image ungeblitzten UB and YQ B a luminance component of the image flashed
  • the weighting factors a, b indicate the weighting of the brightness values of the respective non-flashed image UB, GB.
  • "a + b 1”.
  • Both the non-flashed image UB and the flashed image GB can be generated in an alternative extension of the method according to the invention by superposition of a plurality of non-flash recordings UOB or flashed recordings GOB. This will be explained in more detail with reference to FIG.
  • a modified non-flashed recording UOB 1 is generated from these three non-flashed recordings UOB.
  • the modified non-flashed recording UOB 1 can be calculated by pixel-by-pixel superimposition of the individual unblitzed recordings UOB.
  • a motion compensation BK of the non-flashed recordings UOB can take place before the superimposition by the fourth means M4. With the help of the superposition of several recordings such as the non-flashed recordings UOB, a reduction of the picture noise can be achieved.
  • This image coding device BV is able to carry out the image coding method according to the invention by means of the first, second and third means M1, M2, M3.
  • the picture coding device BV may also include the fourth means M4.
  • the fourth means is integrated in the first and / or second means M1, M2.
  • the first and second means M1, M2 can also be integrated in a single means.
  • the third means M3 can have a motion compensation BK. By this motion compensation BK it is achieved that the unlit image UB and the flashed image GB are motion-compensated before the combination. As a result, it is achieved, for example, that fuzziness in the result image EB is reduced or avoided.
  • the flashed and / or ungeblitzte image GB, UB in particular by at least one image enhancement method BVM ⁇ sondere by noise reduction are prepared qualitatively.
  • a noise suppression filter can be applied to the flashed image GB to reduce the image noise.
  • Further image enhancement methods such as filters for enhancing edges within each image can further improve image quality, it ⁇ rich.
  • the on ⁇ light of ungeblitzten or flashed picture UB, GB Lucas- be set.

Landscapes

  • Engineering & Computer Science (AREA)
  • Multimedia (AREA)
  • Signal Processing (AREA)
  • Image Processing (AREA)
  • Studio Devices (AREA)

Abstract

L'invention concerne un procédé de codage d'image comprenant au moins une capture sans flash et au moins une capture avec flash d'un même motif. Au moins une capture sans flash permet de générer une image sans flash, et au moins une capture avec flash permet de générer une image avec flash. Selon l'invention, au moins la luminosité ou la couleur d'au moins une des images est modifiée pour augmenter le contraste total respectif, et une représentation du résultat est générée par combinaison, en particulier par addition pondérée, de l'image avec flash et de l'image sans flash. Cette invention se rapporte en outre à un dispositif de codage servant à la mise en oeuvre de ce procédé de codage d'image.
EP05850486A 2004-12-23 2005-12-22 Procede de codage d'image, et dispositif de codage d'image Withdrawn EP1829362A1 (fr)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
DE102004062382A DE102004062382A1 (de) 2004-12-23 2004-12-23 Bildcodierverfahren sowie Bildcodiervorrichtung
PCT/EP2005/057096 WO2006069964A1 (fr) 2004-12-23 2005-12-22 Procede de codage d'image, et dispositif de codage d'image

Publications (1)

Publication Number Publication Date
EP1829362A1 true EP1829362A1 (fr) 2007-09-05

Family

ID=35976390

Family Applications (1)

Application Number Title Priority Date Filing Date
EP05850486A Withdrawn EP1829362A1 (fr) 2004-12-23 2005-12-22 Procede de codage d'image, et dispositif de codage d'image

Country Status (4)

Country Link
US (1) US20080131007A1 (fr)
EP (1) EP1829362A1 (fr)
DE (1) DE102004062382A1 (fr)
WO (1) WO2006069964A1 (fr)

Families Citing this family (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US8638317B2 (en) * 2007-03-16 2014-01-28 Japan Display West Inc. Display apparatus and method for controlling the same
TWI472222B (zh) * 2008-09-19 2015-02-01 Altek Corp Image brightness compensation method and digital image pickup device with image brightness compensation
JP5602562B2 (ja) * 2009-10-06 2014-10-08 パナソニック株式会社 画像生成装置、再生装置、再生システム、画像生成方法および再生方法
TWI536829B (zh) * 2012-02-14 2016-06-01 佳能企業股份有限公司 應用影像處理之電子裝置
CN103259972A (zh) * 2012-02-17 2013-08-21 佳能企业股份有限公司 影像处理方法及成像装置
US9218667B2 (en) * 2013-11-25 2015-12-22 International Business Machines Corporation Spherical lighting device with backlighting coronal ring
US10706512B2 (en) * 2017-03-07 2020-07-07 Adobe Inc. Preserving color in image brightness adjustment for exposure fusion

Family Cites Families (14)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4647975A (en) * 1985-10-30 1987-03-03 Polaroid Corporation Exposure control system for an electronic imaging camera having increased dynamic range
US5247366A (en) * 1989-08-02 1993-09-21 I Sight Ltd. Color wide dynamic range camera
JP3540485B2 (ja) * 1995-04-13 2004-07-07 株式会社リコー 電子スチルカメラ
US6219097B1 (en) * 1996-05-08 2001-04-17 Olympus Optical Co., Ltd. Image pickup with expanded dynamic range where the first exposure is adjustable and second exposure is predetermined
US6278490B1 (en) * 1996-05-23 2001-08-21 Olympus Optical Co., Ltd. Exposure control for an image pickup apparatus that uses an electronic flash
US6744471B1 (en) * 1997-12-05 2004-06-01 Olympus Optical Co., Ltd Electronic camera that synthesizes two images taken under different exposures
JP2000100172A (ja) * 1998-07-22 2000-04-07 Mitsubishi Electric Corp 半導体記憶装置
US6825884B1 (en) * 1998-12-03 2004-11-30 Olympus Corporation Imaging processing apparatus for generating a wide dynamic range image
US20020081111A1 (en) * 2000-12-22 2002-06-27 Hirohiko Ina Hybrid camera fill-flash
US6859565B2 (en) * 2001-04-11 2005-02-22 Hewlett-Packard Development Company, L.P. Method and apparatus for the removal of flash artifacts
JP4275344B2 (ja) * 2002-01-22 2009-06-10 富士フイルム株式会社 撮像装置、撮像方法、及びプログラム
JP2003319252A (ja) * 2002-04-26 2003-11-07 Minolta Co Ltd デジタルカメラ
JP3801126B2 (ja) * 2002-09-25 2006-07-26 ソニー株式会社 撮像装置，撮像装置の画像出力方法，およびコンピュータプログラム
US7457477B2 (en) * 2004-07-06 2008-11-25 Microsoft Corporation Digital photography with flash/no flash extension

Non-Patent Citations (1)

* Cited by examiner, † Cited by third party
Title
See references of WO2006069964A1 *

Also Published As

Publication number Publication date
WO2006069964A1 (fr) 2006-07-06
US20080131007A1 (en) 2008-06-05
DE102004062382A1 (de) 2006-07-13

Similar Documents

Publication Publication Date Title
DE69520303T2 (de) Bildabhängige Farbsättigungskorrektur für Bilddarstellungen natürlicher Szenen
DE3751412T2 (de) Verfahren und Vorrichtung zur Bildverarbeitung mit Gradationskorrektur des Bildsignals.
DE69412035T2 (de) Kaskadenartige Bildverarbeitung mit Histogrammvorhersage
DE3447472C2 (fr)
DE3402251C2 (fr)
DE69510710T2 (de) Farbdruck mit erweitertem Dichteumfang
EP1231564B1 (fr) Contrôle local numérique de propriétés d'image au moyen de masques
DE2844158C3 (de) Verfahren zur Reproduktion von Originalvorlagen welche bezüglich ihres Farbgehaltes nach einem Dreibereichsverfahren abgetastet werden
DE69424920T2 (de) Bildabhängige Schärfeverbesserung
EP0927496B1 (fr) Procede et dispositif pour produire une image composite
DE60101013T2 (de) Farbtransformationsverfahren zum Abbilden von Farben in Bildern
DE4492446B4 (de) Schirmfilterungsgrenzenerfassung für eine Bildzusammensetzung
DE69417497T2 (de) Verfahren und Vorrichtung für bildabhängige Farbveränderung
DE3824096C2 (de) Photodrucker
DE2612042A1 (de) Verschiebbares video-mattscheibensystem
DE19811279C2 (de) Verfahren zur automatischen Auswahl von Farbkalibrierungen
DE10051673A1 (de) Verfahren zum verbesserten Kontrastabbilden bei Digitalbildern
DE3810902A1 (de) Aperturkorrekturschaltung
EP1829362A1 (fr) Procede de codage d'image, et dispositif de codage d'image
DE69609180T2 (de) Optimale graustufenabbildung in elektronischen kameras
DE938699C (de) Verfahren zur Wiedergabe farbiger Bilder
DE60030900T2 (de) Bildverarbeitungsverfahren und -system
DE102010045803A1 (de) Verfahren zur Erzeugung einer Bilddatei mit hohem Dynamikumfang - HDR Raw Workflow
DE2600901B2 (de) Farbwertkorrektureinrichtung
DE4104022A1 (de) Farbdruckverfahren fuer die reproduktion von computerbildern

Legal Events

Date Code Title Description
PUAI Public reference made under article 153(3) epc to a published international application that has entered the european phase

Free format text: ORIGINAL CODE: 0009012

17P Request for examination filed

Effective date: 20070605

AK Designated contracting states

Kind code of ref document: A1

Designated state(s): AT BE BG CH CY CZ DE DK EE ES FI FR GB GR HU IE IS IT LI LT LU LV MC NL PL PT RO SE SI SK TR

DAX Request for extension of the european patent (deleted)
RAP1 Party data changed (applicant data changed or rights of an application transferred)

Owner name: CONTINENTAL AUTOMOTIVE GMBH

STAA Information on the status of an ep patent application or granted ep patent

Free format text: STATUS: THE APPLICATION IS DEEMED TO BE WITHDRAWN

18D Application deemed to be withdrawn

Effective date: 20100701