WO2001088860A1 - Method and device - Google Patents

Method and device Download PDF

Info

Publication number
WO2001088860A1
WO2001088860A1 PCT/SE2001/001077 SE0101077W WO0188860A1 WO 2001088860 A1 WO2001088860 A1 WO 2001088860A1 SE 0101077 W SE0101077 W SE 0101077W WO 0188860 A1 WO0188860 A1 WO 0188860A1
Authority
WO
WIPO (PCT)
Prior art keywords
mark
statistics
quality
rejection
threshold value
Prior art date
Application number
PCT/SE2001/001077
Other languages
French (fr)
Other versions
WO2001088860B1 (en
Inventor
Luciano Beghello
Martti Toivakka
Original Assignee
Luciano Beghello
Martti Toivakka
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 Luciano Beghello, Martti Toivakka filed Critical Luciano Beghello
Priority to AU2001260894A priority Critical patent/AU2001260894A1/en
Publication of WO2001088860A1 publication Critical patent/WO2001088860A1/en
Publication of WO2001088860B1 publication Critical patent/WO2001088860B1/en

Links

Classifications

    • GPHYSICS
    • G06COMPUTING; CALCULATING OR COUNTING
    • G06TIMAGE DATA PROCESSING OR GENERATION, IN GENERAL
    • G06T1/00General purpose image data processing
    • G06T1/0021Image watermarking
    • GPHYSICS
    • G07CHECKING-DEVICES
    • G07DHANDLING OF COINS OR VALUABLE PAPERS, e.g. TESTING, SORTING BY DENOMINATIONS, COUNTING, DISPENSING, CHANGING OR DEPOSITING
    • G07D7/00Testing specially adapted to determine the identity or genuineness of valuable papers or for segregating those which are unacceptable, e.g. banknotes that are alien to a currency
    • G07D7/003Testing specially adapted to determine the identity or genuineness of valuable papers or for segregating those which are unacceptable, e.g. banknotes that are alien to a currency using security elements
    • G07D7/0034Testing specially adapted to determine the identity or genuineness of valuable papers or for segregating those which are unacceptable, e.g. banknotes that are alien to a currency using security elements using watermarks
    • GPHYSICS
    • G06COMPUTING; CALCULATING OR COUNTING
    • G06TIMAGE DATA PROCESSING OR GENERATION, IN GENERAL
    • G06T2201/00General purpose image data processing
    • G06T2201/005Image watermarking
    • G06T2201/0065Extraction of an embedded watermark; Reliable detection

Definitions

  • the present invention concerns a method and a device for quality inspection and quality examination of through radiated security elements, such as different types of watermarks, security threads, holograms in patches and in bands, security fibres and other visible security ingredients that may be caught in a medium, either being paper or a plastic like medium, in connection with the through radiation.
  • through radiated security elements such as different types of watermarks, security threads, holograms in patches and in bands, security fibres and other visible security ingredients that may be caught in a medium, either being paper or a plastic like medium, in connection with the through radiation.
  • safety and “security paper” comprises all papers in which any kind of protection against forgery has been provided. This may be provided in different ways according to desires and requirements .
  • a common type is a watermark. Sometimes also a hologram or a kinegram is provided on or in the paper.
  • Another important way of preventing forgery is printing patterns which are difficult to copy, special dye and using printing methods of such a high quality that the access is strongly limited for forgers.
  • Watermarks are created by thicker and thinner portions in the paper during the forming process on a cylinder mould.
  • the thicker portions give a darker impression and the thinner a lighter impression when the paper is held towards a lamplight .
  • cylinder mould cylinder mould two tones
  • cylinder mould half tone watermark cylinder mould half tone watermark.
  • the latter is also called portrait watermark and is the most exclusive.
  • portrait watermark To obtain a good security it is necessary to use a two-tones or preferably a half-tone watermark.
  • Other known types of watermarks are "Electrotype” and "Bar-code” watermarks.
  • a cast of plaster is made on the wax engravement, which forms a mirror copy of the wax plate.
  • each subplate a top plate is deposited and these two are both used to emboss the desired pattern in the copper wire.
  • the completed copper wire is usually welded to other copper wires up to five layers making up an entire wire. This is a precision work. In order to avoid obtaining any disturbing edge the 0.18-0.20 mm thick copper threads are grinded to half and thereafter welded with silver to the grinded threads of another part . When a round wire is obtained it is welded to two stronger copper wires to obtain stability.
  • Hologram and kinegram are nowadays common types of security elements, which are used in for example the Finnish 20, 100 and 500 Mark notes. The difference between hologram and kinegram is that it does not have to be a physical image to produce a kinegram but the image may be created by a computer and by means of laser technology.
  • the present invention concerns a method and a device for checking the quality and the distance between through radiated security elements, such as preferably different types of watermarks, but also hologram and the like, security threads, security fibres, by means of image analysis.
  • radiated security elements such as preferably different types of watermarks, but also hologram and the like, security threads, security fibres, by means of image analysis.
  • the expression through radiation of security elements refer to any kind of radiation that may be used to register density differences in the paper, for example, transmitting visual light or IR-light or X-rays through the security element/s.
  • the present invention states a method and a device for through radiation of the different security elements comprised in valuable documents with image analysis processing for the establishing of its quality, dimensions and distance there between.
  • the present invention is also directed to analysis and quality examination of through radiated areas around, in the vicinity of the security elements comprised in the valuable document .
  • the quality is examined concerning the homogeneity of the document, for example concerning the variation of the fibre distribution in small scale over a predetermined surface area, called formation in the art of paper manufacturing. This is determined by calculating a formation coefficient distributed in different wave length areas .
  • the security element for example a watermark
  • radiated for example with light of a wavelength within the visual interval or of another type : for example infrared or ultra violet light or X-rays
  • the method may also comprise at least any one of the following steps : correction of the area weight (weight per unit of area, which is a critical parameter for, for example, the light absorption of the paper) with an average value of the same;
  • test mark has approved quality from a predetermined threshold level for differences in the statistics between the reference and the test mark
  • Rejection of the quality of the mark is provided according to an embodiment of the invention if its average value of weight per unit of area in the valuable document exceeds a maximum threshold value for the average according to said predetermined statistics.
  • Rejection of the quality of the mark is provided in a further embodiment of the invention if its average value of weight per unit of area in the valuable document is below a minimum threshold value for the average value according to said predetermined statistics.
  • Rejection of the quality of the mark is provided in another embodiment of the present invention if its rotation in relation to said mask exceeds a predetermined rotational threshold value in degrees according to said predetermined statistics. Rejection of the quality of the mark is provided in a further embodiment if its rotation in relation to said mask exceeds a predetermined rotational threshold value in degrees according to said predetermined statistics in combination with said maximum threshold value .
  • Rejection of the quality of the mark is provided in another embodiment of the present invention if its rotation in relation to said mask exceeds a predetermined rotational threshold value in degrees according to said predetermined statistics in combination with said minimum threshold value.
  • Rejection of the quality of the mark is provided in an embodiment of the invention if the shrinkage factor differs in relation to the predetermined statistics of the same.
  • Rejection of the quality of the mark is provided in further embodiments of the invention if the shrinkage factor differs in relation to the predetermined statistics in combination with said statistics for other values and/or factors.
  • the statistics is used in an embodiment to check the distance between watermarks and/or other security elements in a row of valuable paper at manufacturing thereof in a machine for this purpose .
  • the statistics are used for checking the distance between security elements in a row of valuable paper in the so-called machine direction in an embodiment of the present invention. In a further embodiment of the present invention the statistics are used for checking the distance between marks in a row of valuable paper crosswise the machine direction and the row in front.
  • the statistics are used to check the distance between marks in a row of valuable paper in the so called machine direction and crosswise the machine direction to the row in front .
  • the mark is a watermark.
  • Through radiation is effected in one embodiment of the invention by means of at least two different wavelengths for the light so that at least two formation indexes is obtained for statistical determination of the quality of a mark.
  • Statistics is created in one embodiment when a reference mark is registered, whereby a mark to be tested immediately may be registered for quality determination by means of the statistics for the reference mark.
  • the present invention comprises a device for quality examination of the through radiated security element comprised in the valuable document by means of image analysis processing for the determination of its quality.
  • a device for quality examination of the through radiated security element comprised in the valuable document by means of image analysis processing for the determination of its quality.
  • Through radiation is provided, whereby radiation passing is registered by means of digital means for receiving transmitted radiation, which means is connected or connectable to computer means for analysis of the quality of the security element .
  • the device may also comprise at least one of the means below;
  • correcting means for the average value of weight per unit of area of the valuable document and with the size of the reference or test mark according to the original (design) ;
  • digital cutting means for cutting the image of the mark to the size of the original
  • analysis means for determination of statistics for different values by means of analysis of the mark if it is a reference mark, in comparison with an original mark, design mark, whereby the statistics is used for quality check of test marks;
  • checking means for checking of the radiation permeability of the test mark in comparison with a threshold value for the same in said statistics
  • rejection communication means for the quality of the test mark if the radiation permeability is lower than the threshold value, whereby the quality check is interrupted giving a communication of the quality
  • digital comparison means for the comparison between the test mark and the reference mark if the radiation permeability is greater than said threshold value, whereby a mask with the contour of the original mark is overlapping the test mark; determination means for determination of differences in radiation permeability between the reference mark and the test mark within the mask for defined areas of the mark where the difference is pronounced in comparison with statistics over acceptable differences;
  • determination means for determination if the mark is approved according to a predetermined threshold level for differences in the statistics
  • communication means for communicating said differences in the statistics and possible acceptance or rejection of the quality of the test mark.
  • the device may further perform steps in the method in accordance with the appended dependent device claims .
  • Fig. 1 illustrates schematically a watermark analysis according to the present invention.
  • Fig. 2 illustrates a watermark and some parameters for quality examination according to the present invention .
  • Fig. 3 illustrates a masking of an image background according to the present invention.
  • Fig. 4 illustrates schematically fault localisation of a watermark according to the present invention.
  • Fig. 5 illustrates schematically the distance between different security elements, here watermarks, at manufacturing of valuable documents according to the present invention.
  • Fig. 6 illustrates schematically dimensional determination and register, here for a bank note with different types of security inserts.
  • Fig. 7 illustrates a formation index for different wave lengths according to the present invention.
  • Fig. 8 illustrates schematically different types of security inserts or security prints, which may be quality determined according to the present invention .
  • the present invention concerns analysis and quality judgement of through radiated security elements comprised in valuable documents.
  • image analysis processing of the invention with analysis of geometrical factors of the security elements, such as watermarks, whereby such factors are length and width relations (aspect ratio) , comparison in relation to an original (design) , a reference mark or reference image and background information, so called formation, are intended.
  • laboratory and manufacturing scale information "on-line" such as the distance between several watermarks and/or other security elements, such as security thread, hologram, is intended at the same time .
  • Fig. 1 illustrates schematically a watermark analysis 10 according to the invention.
  • one or more watermarks are registered 12, during manufacturing (see Fig. 5) in a computer (not shown) by means of digital means for registration of received light, for example a digital camera (not shown) .
  • the test mark 16 has then been through radiated via for example a shining table, whereby the mark transmits different amounts of light at different grey scales of the ornament of the mark.
  • parameters 14 is input or determined at the analysis 10 for admissible scale deviation, rotation "max rot", length and width relation "max aspect ratio” .
  • the originally produced mark (design) 18 is comprised and used to form a digital contour mask 20 for the mark and a reference mark 22 approved as manufactured according to recognised practice for manufacturing of value marks.
  • the mask 20 is overlapped over the reference mark 22 whereby, statistics 24 and threshold values for the through radiation with light is produced.
  • This statistic 24 is dependent of the formation of the valuable document, i.e. the fibre distribution in small scale at analysis of valuable paper and surface weight, so called “gramages" weight per square meter, commonly g/m 2 (Amer. : basis weight) .
  • Obtained statistics 24 may comprise for example the following statistical determination methods, WMD (Mean Absolute
  • PSNR Peak Signal to Noice Ratio
  • mWMD masked Mean Absolute Difference
  • mPSNR masked Peak Signal to Noice Ratio
  • CC1-2D Correlation Coefficient Unmasked Images
  • CC2-2D Correlation Coefficient Unmasked Images on nonzero pixels
  • mCCl-2D Correlation Coefficients Masked Images
  • mCC2-2D Correlation Coefficients Normalized Masked Images
  • mCC3 see mCCl
  • Fit3D (3D adaptation for the designed mark 18)
  • Scale 3D Optimum 3D-scale for calculation of Fit3D
  • rejection is meant that what is rejected is not accepted due to poor quality.
  • Fig. 1 illustrates by means of arrows which results that a mark analysis 10 may perform in the form of defect localisation 26, dimensions and registers (see Fig. 6) , statistics, background information (Fig. 7) etc.
  • the through radiation is metered for the mark 16 under test, whereby it immediately is determined if the analysis should be interrupted at the registration due to the permeability is too high or too low in relation to a predetermined threshold value. If this * occurs, it is not any idea to carry on with the analysis since already the input, registration of the mark reveals deficiencies in it .
  • a device for quality examination of through radiated security elements comprised in valuable documents by means of image analysis processing for the stipulation of its quality, dimensions and internal distances .
  • the device comprises means (for example, shining table or IR- lamp) for through radiation, which radiates through the mark, whereby the radiation hitting digital means (for example a digital camera) for receiving transmitted radiation is registered, which means is connected or connectable to computer means (for example a personal computer or other computer) for analysis of the quality of the mark. Further, the device comprises :
  • correction means for the average value of weight per unit of area of the valuable document and with the size of the reference 22 or test mark 16 according to the original (design) 18;
  • analysis means for determination of statistics for different values by means of analysis of the mark if it is a reference 22, in comparison with an original mark 18, whereby the statistics is used for quality check of test marks 16;
  • check means for checking the radiation permeability of the test mark 16 in comparison, with a threshold value for the same in said statistics
  • digital comparison means for comparison of the test mark 16 with the reference mark 22 if the radiation permeability is greater than said threshold value, whereby a mask 20 with the contour of the original mark is overlapped over the test mark 16;
  • determination means for the determination of differences in radiation transmittance between the reference mark 22 and test mark 16 within the mask 20 for defined areas of the mark where the difference is pronounced in comparison with statistics over acceptable differences;
  • determination means for determination if the mark is approved based on a predetermined threshold for differences in the statistics
  • communication means for communicating said differences in statistics and possible acceptance or rejection of the quality of the test mark 16.
  • a unique property of the device and the method according to the present invention is provided by the fact that the statistics 24 may be created with the device when the designed mark 18 is used as original/reference, whereby the real reference 22 is used as a test mark 16.
  • Rejection of the quality of the mark is performed if its average value of weight per unit of area in the valuable document exceeds a maximum threshold value for the average value according to said predetermined statistics .
  • Rejection of the quality of the mark is performed if its average value of weight per unit of area in the valuable document is below a minimum threshold value for the average value according to said predetermined statistics .
  • Rejection of the quality of the mark is performed if its rotation in relation to said mask exceeds a predetermined rotational threshold value in degrees according to said predetermined statistics.
  • Rejection of the quality of the mark is performed if its rotation in relation to said mask exceeds a predetermined rotational threshold in degrees according to said predetermined statistics in combination with said maximum threshold value.
  • Rejection of the quality of the mark is performed if its rotation in relation to said mask exceeds a predetermined rotational threshold value in degrees according to said predetermined statistics in combination with said minimum threshold value . Rejection of the quality of the mark is performed if the shrinking factor differs in relation to the predetermined statistics.
  • the shrinking factor comes from the tendency of a mark to shrink from its original size at manufacturing of for example a value paper having a watermark when joining paper sheets, for example due to moisture and solvents that have been applied.
  • Fig. 2 illustrates a watermark with an indicated height and width. The relation between these parameters is used in the invention to determine the quality of a mark.
  • the mark there is an arrow, which indicate possible rotation of the mark in degrees at a digital cut of the mark at analysis 10.
  • Fig. 3 illustrates a masking of the background 30 of a mark, i.e. the contour 32 of the mark emerges according to the masking 20.
  • the mask 20 masks the background 30 of the test image 22. The method has previously been described above.
  • Fig. 4 illustrates as an embodiment of the invention fault localisation in the analysis 10.
  • the test mark 16 is here divided in an embodiment of the invention into a closer masked net (cross-ruled area) from image to image when it is compared with the reference 22.
  • the plus signs indicate statistical differences of the test mark 16 in comparison with the reference mark 22.
  • the first deviation shows a white patch in the upper left cross-ruled area of the tested mark 16, which is missing in the reference mark 22. This quality deviation has been marked with a plus sign to the right of the tested mark 16 for the checker in concern.
  • the cross-ruled area is made with a finer mask for the subsequent tested marks 16 in fig. 4.
  • the new cross-ruled area comprising sixteen checkers a further statistical deviation is discovered in the quality of the tested mark 16, which has been indicated by a plus sign in the second checker in the lowest row of checkers .
  • the deviation is a black spot on the shirt collar in the test mark 16.
  • cross-ruled area may be made even finer masked, which is shown in the mark 16 furthest down, which has been divided into 64 checkers, whereby another statistical deviation is discovered. This time it is a rupture in the contour line of the face in the mark 16.
  • the finer marked the cross-ruled area is the more statistics, since the statistics refers to each checker.
  • fig. 5 it is illustrated schematically how tested marks 16, at manufacturing, is positioned in rows and columns in the machine direction (vertical arrow) and cross wise the machine direction (horizontal arrow) on a valuable paper sheet, whereby the machine direction is the direction the sheet is transported in a manufacturing machine.
  • produced statistics are used to check the distance between the watermarks in a row of valuable papers at manufacturing of the same in a machine for this purpose.
  • a faulty printing of the valuable paper sheet thus may be stopped when too large statistical deviations for distance between marks 16 arise both in the machine direction and the cross wise machine direction, which is shown with double arrows at the valuable paper sheet in fig. 5.
  • Fig. 6 illustrates schematically dimension determination and register, here for a bank note with different types of security inserts or security prints . It should be noted that security inserts that are not in themselves possible to though radiated with advantage may be through radiated in its immediate vicinity, for example the surroundings, for example by means of the method according to fig. 7.
  • fig. 6 different distances is illustrated, which may be checked for examination of the quality. Arrows in fig. 6 indicate the distances . The distances are measured on the security elements described in more detailed in fig. 8.
  • Fig. 7 illustrates a formation index for different wavelengths according to the present invention.
  • Such a range is shown to the right of the columns in fig. 7, whereby a formation index for the range may be obtained from the column diagram in fig. 7, which is different for different wave lengths of the light coming from the one and same image . Sampling and rescaling of the image produce the different wavelengths. Thus, it is possible to obtain a more accurate quality examination if several wavelengths in the image are analysed.
  • Fig. 8 illustrates different types of security inserts or security prints, which may be quality determined according to the present invention.
  • the security elements are security inserts, security prints etc. and comprises here of portrait watermark, text watermark, security thread, foil in a band, coated areas, number watermark, patch foil, applied elements, such as hologram.

Abstract

The invention concerns a method and a device for quality examination of through radiated security elements (16, 22) comprised in a valuable document by image analysis processing for the determination of its quality, dimensions and internal distances. The security element may specifically be a watermark. The quality of the security element (16, 22) is determined via statistical analysis, whereby this is determined via previously obtained statistics and via threshold values.

Description

TECHNICAL FIELD
The present invention concerns a method and a device for quality inspection and quality examination of through radiated security elements, such as different types of watermarks, security threads, holograms in patches and in bands, security fibres and other visible security ingredients that may be caught in a medium, either being paper or a plastic like medium, in connection with the through radiation.
TECHNICAL BACKGROUND
The expressions "safety" and "security paper" comprises all papers in which any kind of protection against forgery has been provided. This may be provided in different ways according to desires and requirements . A common type is a watermark. Sometimes also a hologram or a kinegram is provided on or in the paper.
Another important way of preventing forgery is printing patterns which are difficult to copy, special dye and using printing methods of such a high quality that the access is strongly limited for forgers.
Almost every security paper is designed for its special purpose, for example, a passport paper for a passport of one country is only made for this country, all this for trying to make this paper as unique as possible .
Concerning watermarks it may be stated that a true watermark always is achieved by a cylinder mould or on a forming cylinder. It is also possible to obtain something reminding of a watermark by embossing the paper in a flat wire machine, where a mark is embossed in the paper by means of a top couch roller, also called "dandy roll" . However, this mark shows less quality than an approved watermark and is only used in more exclusive civil papers or when the value of the document is low.
In order to provide a true watermark a substantially more advanced technique is required. Watermarks are created by thicker and thinner portions in the paper during the forming process on a cylinder mould. The thicker portions give a darker impression and the thinner a lighter impression when the paper is held towards a lamplight .
There are three different types of true watermarks: cylinder mould, cylinder mould two tones and cylinder mould half tone watermark. The latter is also called portrait watermark and is the most exclusive. To obtain a good security it is necessary to use a two-tones or preferably a half-tone watermark. Other known types of watermarks are "Electrotype" and "Bar-code" watermarks.
To check that a watermark is true a visual examination is made today. The paper with the watermark is put on a black paper. If it is a true watermark the thicker portions of the mark looks whiter while the thinner portions become dark. It is also possible to illuminate the paper with ultra violet light, in which light a true watermark is hardly seen. An embossed watermark may fluoresce alternatively obstruct the fluorescence of the paper, but this does not apply to paper made of non-fluorescent fibres as for example cotton. It also exists three paper forgeries where the middle sheet have had an embossed watermark, for example forgeries of French ID cards . These forgeries commonly give unusually sharp nuance transitions. Therefore, soft transitions are put into true watermarks .
It also happens that a true watermark has been photographed. Printing a disturbing print over portions of the watermark prevents this opportunity. The print may of course not disturb as much so the check of the quality is made more difficult. Generally a watermark is considered to give the best security but if the value of the document is high it usually is combined with for example one or two other types of watermarks and a security thread.
In order to provide a true watermark a high technology and skilled personnel is required as stated above. Nowadays image analysis technology is used to rapidly and securely create a new watermark. The new technology facilitates the production of three dimensionally images, which are used subsequently for the engraving of wire embosses with automatic milling machines. The traditional production of a watermark is still in use. A short run-through will follow point by point.
First an artist engraves the original in a wax plate . The artist must take into consideration, which portions to be light and dark, respectively, in the paper. Also the fact that the paper is subjected to strain tensions and will be slightly stretched in the paper machine must be taken into consideration. In order to avoid getting a stretched image a compressed image of the original is engraved so that a normal image will be obtained in the paper. The portions which shall be dark obtains a higher profile than a zero plane in a wax. Plate and the portions which shall be light obtains a lower profile than the zero plane of the wax plate .
1. A cast of plaster is made on the wax engravement, which forms a mirror copy of the wax plate.
2. On the plaster plate a copper plate is deposited, a so- called master, which is identical with the wax engravement .
3. On the master a copper matrix is deposited, which is a copy of the plaster plates. This is used only for the manufacturing of new subplates .
4. On the matrix as many subplates as is required to make up a wire, i.e. the wire arranged on the cylinder mould or forming cylinder.
5. On each subplate a top plate is deposited and these two are both used to emboss the desired pattern in the copper wire.
The completed copper wire is usually welded to other copper wires up to five layers making up an entire wire. This is a precision work. In order to avoid obtaining any disturbing edge the 0.18-0.20 mm thick copper threads are grinded to half and thereafter welded with silver to the grinded threads of another part . When a round wire is obtained it is welded to two stronger copper wires to obtain stability. Hologram and kinegram are nowadays common types of security elements, which are used in for example the Finnish 20, 100 and 500 Mark notes. The difference between hologram and kinegram is that it does not have to be a physical image to produce a kinegram but the image may be created by a computer and by means of laser technology. This protection prevents colour photo copying, which means that this could be an interesting complement, since the development of better and better colour photo-copying machines is rapid. The application on the bank note is made by heat sealing. It is also possible to combine kinegram and hologram with microprint .
An important factor when analysing valuable documents, such as bank note paper, passport paper, security document paper and other security paper is the homogeneity of the document, for example regarding its variation in fibre distribution in small scale over a determined surface, called formation in the art of paper manufacturing.
SUMMARY OF THE DESCRIBED INVENTION
The present invention concerns a method and a device for checking the quality and the distance between through radiated security elements, such as preferably different types of watermarks, but also hologram and the like, security threads, security fibres, by means of image analysis.
In the present application the expression through radiation of security elements refer to any kind of radiation that may be used to register density differences in the paper, for example, transmitting visual light or IR-light or X-rays through the security element/s. In order to obtain adequate quality analysis of the security elements the present invention states a method and a device for through radiation of the different security elements comprised in valuable documents with image analysis processing for the establishing of its quality, dimensions and distance there between.
The present invention is also directed to analysis and quality examination of through radiated areas around, in the vicinity of the security elements comprised in the valuable document .
By means of image analysis of valuable documents, such as bank note paper, passport paper, security document paper and other security paper, the quality also is examined concerning the homogeneity of the document, for example concerning the variation of the fibre distribution in small scale over a predetermined surface area, called formation in the art of paper manufacturing. This is determined by calculating a formation coefficient distributed in different wave length areas .
The security element (for example a watermark) is through radiated (for example with light of a wavelength within the visual interval or of another type : for example infrared or ultra violet light or X-rays) , the radiation passing is registered by digital means for the receiving of transmitted radiation. The method may also comprise at least any one of the following steps : correction of the area weight (weight per unit of area, which is a critical parameter for, for example, the light absorption of the paper) with an average value of the same;
determination of statistics for the different values by analysis of the mark if it is a reference mark, compared to an original or design mark, the statistics are used for quality check of test marks;
storing of produced statistics for the reference mark and of the reference mark;
correction of the size of the reference or test mark according to original, design mark and digital cutting of the representation of the mark to the size of the original;
checking of the radiation permeability of a test mark compared to a determined threshold value for the same in said statistics;
rejection of the quality of the test mark if the radiation permeability is less than the threshold value, whereby the quality check is interrupted;
digital comparison of the reference mark with the test mark if the radiation permeability is greater than said threshold, whereby a mask with the outline of the original mark is provided overlapping the mark;
determination of the difference in radiation transmittaiice between the reference mark and the test mark within the mask for the defined area of the marks where the difference is pronounced in comparison with acceptable statistics for acceptable difference;
statistic determination of differences between the reference mark and the test mark by comparison of the same with said produced statistics for quality determination of the test mark in said areas;
determining if the test mark has approved quality from a predetermined threshold level for differences in the statistics between the reference and the test mark; and
communication of said differences in the statistics and possible acceptance or rejection of the quality of the mark.
Rejection of the quality of the mark is provided according to an embodiment of the invention if its average value of weight per unit of area in the valuable document exceeds a maximum threshold value for the average according to said predetermined statistics.
Rejection of the quality of the mark is provided in a further embodiment of the invention if its average value of weight per unit of area in the valuable document is below a minimum threshold value for the average value according to said predetermined statistics.
Rejection of the quality of the mark is provided in another embodiment of the present invention if its rotation in relation to said mask exceeds a predetermined rotational threshold value in degrees according to said predetermined statistics. Rejection of the quality of the mark is provided in a further embodiment if its rotation in relation to said mask exceeds a predetermined rotational threshold value in degrees according to said predetermined statistics in combination with said maximum threshold value .
Rejection of the quality of the mark is provided in another embodiment of the present invention if its rotation in relation to said mask exceeds a predetermined rotational threshold value in degrees according to said predetermined statistics in combination with said minimum threshold value.
Rejection of the quality of the mark is provided in an embodiment of the invention if the shrinkage factor differs in relation to the predetermined statistics of the same.
Rejection of the quality of the mark is provided in further embodiments of the invention if the shrinkage factor differs in relation to the predetermined statistics in combination with said statistics for other values and/or factors.
The statistics is used in an embodiment to check the distance between watermarks and/or other security elements in a row of valuable paper at manufacturing thereof in a machine for this purpose .
The statistics are used for checking the distance between security elements in a row of valuable paper in the so-called machine direction in an embodiment of the present invention. In a further embodiment of the present invention the statistics are used for checking the distance between marks in a row of valuable paper crosswise the machine direction and the row in front.
In another embodiment of the invention the statistics are used to check the distance between marks in a row of valuable paper in the so called machine direction and crosswise the machine direction to the row in front .
In a preferred embodiment of the invention the mark is a watermark.
Through radiation is effected in one embodiment of the invention by means of at least two different wavelengths for the light so that at least two formation indexes is obtained for statistical determination of the quality of a mark.
Statistics is created in one embodiment when a reference mark is registered, whereby a mark to be tested immediately may be registered for quality determination by means of the statistics for the reference mark.
Further, the present invention comprises a device for quality examination of the through radiated security element comprised in the valuable document by means of image analysis processing for the determination of its quality. Through radiation is provided, whereby radiation passing is registered by means of digital means for receiving transmitted radiation, which means is connected or connectable to computer means for analysis of the quality of the security element . The device may also comprise at least one of the means below;
correcting means for the average value of weight per unit of area of the valuable document and with the size of the reference or test mark according to the original (design) ;
digital cutting means for cutting the image of the mark to the size of the original;
analysis means for determination of statistics for different values by means of analysis of the mark if it is a reference mark, in comparison with an original mark, design mark, whereby the statistics is used for quality check of test marks;
digital storing means for obtained statistics for the reference mark and of the reference mark;
checking means for checking of the radiation permeability of the test mark in comparison with a threshold value for the same in said statistics;
rejection communication means for the quality of the test mark if the radiation permeability is lower than the threshold value, whereby the quality check is interrupted giving a communication of the quality;
digital comparison means for the comparison between the test mark and the reference mark if the radiation permeability is greater than said threshold value, whereby a mask with the contour of the original mark is overlapping the test mark; determination means for determination of differences in radiation permeability between the reference mark and the test mark within the mask for defined areas of the mark where the difference is pronounced in comparison with statistics over acceptable differences;
statistical means for calculation of the difference and for comparison of the same with said statistics for quality determination of the test mark in said areas;
determination means for determination if the mark is approved according to a predetermined threshold level for differences in the statistics; and
communication means for communicating said differences in the statistics and possible acceptance or rejection of the quality of the test mark.
The device may further perform steps in the method in accordance with the appended dependent device claims .
SHORT DESCRIPTION OF THE DRAWINGS
In the following text describing examples and embodiments it is referred to the appended figures for a better understanding of the present invention.
Fig. 1 illustrates schematically a watermark analysis according to the present invention. Fig. 2 illustrates a watermark and some parameters for quality examination according to the present invention .
Fig. 3 illustrates a masking of an image background according to the present invention.
Fig. 4 illustrates schematically fault localisation of a watermark according to the present invention.
Fig. 5 illustrates schematically the distance between different security elements, here watermarks, at manufacturing of valuable documents according to the present invention.
Fig. 6 illustrates schematically dimensional determination and register, here for a bank note with different types of security inserts.
Fig. 7 illustrates a formation index for different wave lengths according to the present invention; and
Fig. 8 illustrates schematically different types of security inserts or security prints, which may be quality determined according to the present invention .
DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS
The present invention concerns analysis and quality judgement of through radiated security elements comprised in valuable documents. For example; image analysis processing of the invention with analysis of geometrical factors of the security elements, such as watermarks, whereby such factors are length and width relations (aspect ratio) , comparison in relation to an original (design) , a reference mark or reference image and background information, so called formation, are intended. Additionally, laboratory and manufacturing scale information "on-line", such as the distance between several watermarks and/or other security elements, such as security thread, hologram, is intended at the same time .
Fig. 1 illustrates schematically a watermark analysis 10 according to the invention. Here, one or more watermarks are registered 12, during manufacturing (see Fig. 5) in a computer (not shown) by means of digital means for registration of received light, for example a digital camera (not shown) . The test mark 16 has then been through radiated via for example a shining table, whereby the mark transmits different amounts of light at different grey scales of the ornament of the mark.
Further, parameters 14 is input or determined at the analysis 10 for admissible scale deviation, rotation "max rot", length and width relation "max aspect ratio" .
In the analysis 10, the originally produced mark (design) 18 is comprised and used to form a digital contour mask 20 for the mark and a reference mark 22 approved as manufactured according to recognised practice for manufacturing of value marks. The mask 20 is overlapped over the reference mark 22 whereby, statistics 24 and threshold values for the through radiation with light is produced. This statistic 24 is dependent of the formation of the valuable document, i.e. the fibre distribution in small scale at analysis of valuable paper and surface weight, so called "gramages" weight per square meter, commonly g/m2 (Amer. : basis weight) .
Additionally, statistics 24 for the length and width ratio for a digitally scanned and cut out reference value mark 22 and the rotation of the mark in relation to the mask 20 is produced.
Obtained statistics 24 may comprise for example the following statistical determination methods, WMD (Mean Absolute
Difference) , PSNR (Peak Signal to Noice Ratio) , mWMD (masked Mean Absolute Difference) , mPSNR (masked Peak Signal to Noice Ratio) , CC1-2D (Correlation Coefficient Unmasked Images) , CC2-2D (Correlation Coefficient Unmasked Images on nonzero pixels) , mCCl-2D (Correlation Coefficients Masked Images) , mCC2-2D (Correlation Coefficients Normalized Masked Images) , mCC3 (see mCCl) , Fit3D (3D adaptation for the designed mark 18) , Scale 3D (Optimum 3D-scale for calculation of Fit3D) .
When one or more of these statistics differences between the design mark 18 and the reference mark 22 are registered in the analysis, acceptable differences are stipulated in the form of threshold values for disturbance levels, which are used for stipulation the quality of the test mark 16. The level for the quality 26 of the mark is shown via, for example, a print-out or a computer display in the form of an image with for example marked cross-rule areas (see fig. 4 for a more detailed description of this) where the differences between the reference mark 22 and the test mark 16 are greatest according to said statistics. The differences may of course be shown by other means known to the skilled person within the scope of the present invention. Obtained statistics may in one embodiment of the invention concern each cross-rule area per se, in such a way the statistics become more detailed dependent on now finely cross-ruled area has been used, see fig. 4.
The expression rejection is meant that what is rejected is not accepted due to poor quality.
Fig. 1 illustrates by means of arrows which results that a mark analysis 10 may perform in the form of defect localisation 26, dimensions and registers (see Fig. 6) , statistics, background information (Fig. 7) etc.
In one embodiment the through radiation is metered for the mark 16 under test, whereby it immediately is determined if the analysis should be interrupted at the registration due to the permeability is too high or too low in relation to a predetermined threshold value. If this* occurs, it is not any idea to carry on with the analysis since already the input, registration of the mark reveals deficiencies in it .
In order to carry out the analysis 10 it is given by the present invention a device for quality examination of through radiated security elements comprised in valuable documents by means of image analysis processing for the stipulation of its quality, dimensions and internal distances .
The device comprises means (for example, shining table or IR- lamp) for through radiation, which radiates through the mark, whereby the radiation hitting digital means (for example a digital camera) for receiving transmitted radiation is registered, which means is connected or connectable to computer means (for example a personal computer or other computer) for analysis of the quality of the mark. Further, the device comprises :
correction means for the average value of weight per unit of area of the valuable document and with the size of the reference 22 or test mark 16 according to the original (design) 18;
digital cutting means for cutting of the image of the mark to the size of the original;
analysis means for determination of statistics for different values by means of analysis of the mark if it is a reference 22, in comparison with an original mark 18, whereby the statistics is used for quality check of test marks 16;
digital storing means for produced statistics for the reference mark 22 and of the reference mark 22;
check means for checking the radiation permeability of the test mark 16 in comparison, with a threshold value for the same in said statistics;
rejection communicating means for the quality of the test mark 16 if the radiation permeability is less than the threshold value, whereby the quality check is interrupted with a communication about the quality;
digital comparison means for comparison of the test mark 16 with the reference mark 22 if the radiation permeability is greater than said threshold value, whereby a mask 20 with the contour of the original mark is overlapped over the test mark 16;
determination means for the determination of differences in radiation transmittance between the reference mark 22 and test mark 16 within the mask 20 for defined areas of the mark where the difference is pronounced in comparison with statistics over acceptable differences;
statistical means for calculation of the difference and for comparison of the same with said statistics for quality determination of the test mark 16 in said areas;
determination means for determination if the mark is approved based on a predetermined threshold for differences in the statistics; and
communication means for communicating said differences in statistics and possible acceptance or rejection of the quality of the test mark 16.
A unique property of the device and the method according to the present invention is provided by the fact that the statistics 24 may be created with the device when the designed mark 18 is used as original/reference, whereby the real reference 22 is used as a test mark 16.
The above mentioned means may suitably be built up of software or in a combination with hardware previously known to the skilled person within the art . Below some preferred embodiments of the present invention will follow, which may be performed by the device or the method according to the present invention.
Rejection of the quality of the mark is performed if its average value of weight per unit of area in the valuable document exceeds a maximum threshold value for the average value according to said predetermined statistics .
Rejection of the quality of the mark is performed if its average value of weight per unit of area in the valuable document is below a minimum threshold value for the average value according to said predetermined statistics .
Rejection of the quality of the mark is performed if its rotation in relation to said mask exceeds a predetermined rotational threshold value in degrees according to said predetermined statistics.
Rejection of the quality of the mark is performed if its rotation in relation to said mask exceeds a predetermined rotational threshold in degrees according to said predetermined statistics in combination with said maximum threshold value.
Rejection of the quality of the mark is performed if its rotation in relation to said mask exceeds a predetermined rotational threshold value in degrees according to said predetermined statistics in combination with said minimum threshold value . Rejection of the quality of the mark is performed if the shrinking factor differs in relation to the predetermined statistics.
Rejection of the quality of the mark is performed if the shrinking factor differs in relation to the predetermined statistics in combination with said statistics for other values and/or factors . The shrinking factor comes from the tendency of a mark to shrink from its original size at manufacturing of for example a value paper having a watermark when joining paper sheets, for example due to moisture and solvents that have been applied.
If certain rotation is measured but the value is below the threshold value a correction must be done for the measured rotation so that the rest of the statistical values may be comparable. The corresponding is true for the shrinking factor.
Fig. 2 illustrates a watermark with an indicated height and width. The relation between these parameters is used in the invention to determine the quality of a mark. In the mark there is an arrow, which indicate possible rotation of the mark in degrees at a digital cut of the mark at analysis 10.
Fig. 3 illustrates a masking of the background 30 of a mark, i.e. the contour 32 of the mark emerges according to the masking 20. The mask 20 masks the background 30 of the test image 22. The method has previously been described above.
Fig. 4 illustrates as an embodiment of the invention fault localisation in the analysis 10. The test mark 16 is here divided in an embodiment of the invention into a closer masked net (cross-ruled area) from image to image when it is compared with the reference 22. The plus signs indicate statistical differences of the test mark 16 in comparison with the reference mark 22. The minus signs for each checker indicates good conformity between the reference mark 22 and the test mark 16. In this comparison it was determined that the difference between the both marks where Δ = 15.2, which is accepted or rejected according to predetermined threshold values in the analysis 10, which determined the threshold values from statistical analysis according to any of the above methods for statistical determination of the designed value in comparison with the reference 22.
The first deviation shows a white patch in the upper left cross-ruled area of the tested mark 16, which is missing in the reference mark 22. This quality deviation has been marked with a plus sign to the right of the tested mark 16 for the checker in concern.
The cross-ruled area is made with a finer mask for the subsequent tested marks 16 in fig. 4. In the new cross-ruled area comprising sixteen checkers a further statistical deviation is discovered in the quality of the tested mark 16, which has been indicated by a plus sign in the second checker in the lowest row of checkers . The deviation is a black spot on the shirt collar in the test mark 16.
In similar ways the cross-ruled area may be made even finer masked, which is shown in the mark 16 furthest down, which has been divided into 64 checkers, whereby another statistical deviation is discovered. This time it is a rupture in the contour line of the face in the mark 16. The finer marked the cross-ruled area is the more statistics, since the statistics refers to each checker.
In fig. 5 it is illustrated schematically how tested marks 16, at manufacturing, is positioned in rows and columns in the machine direction (vertical arrow) and cross wise the machine direction (horizontal arrow) on a valuable paper sheet, whereby the machine direction is the direction the sheet is transported in a manufacturing machine. In this embodiment of the present invention produced statistics are used to check the distance between the watermarks in a row of valuable papers at manufacturing of the same in a machine for this purpose. Here, a faulty printing of the valuable paper sheet thus may be stopped when too large statistical deviations for distance between marks 16 arise both in the machine direction and the cross wise machine direction, which is shown with double arrows at the valuable paper sheet in fig. 5.
Fig. 6 illustrates schematically dimension determination and register, here for a bank note with different types of security inserts or security prints . It should be noted that security inserts that are not in themselves possible to though radiated with advantage may be through radiated in its immediate vicinity, for example the surroundings, for example by means of the method according to fig. 7.
In fig. 6 different distances is illustrated, which may be checked for examination of the quality. Arrows in fig. 6 indicate the distances . The distances are measured on the security elements described in more detailed in fig. 8. Fig. 7 illustrates a formation index for different wavelengths according to the present invention. By means of image analysis of valuable documents, such as bank note paper, passport paper, security document paper, other security paper etc, also the quality of the homogeneity of the document in for example its variating fibre distribution in small scale over a determined area, called formation within the field of paper manufacturing, is also examined. This is determined by calculating a formation coefficient distributed in different wavelength ranges .
Such a range is shown to the right of the columns in fig. 7, whereby a formation index for the range may be obtained from the column diagram in fig. 7, which is different for different wave lengths of the light coming from the one and same image . Sampling and rescaling of the image produce the different wavelengths. Thus, it is possible to obtain a more accurate quality examination if several wavelengths in the image are analysed.
Fig. 8 illustrates different types of security inserts or security prints, which may be quality determined according to the present invention. The security elements are security inserts, security prints etc. and comprises here of portrait watermark, text watermark, security thread, foil in a band, coated areas, number watermark, patch foil, applied elements, such as hologram.
The present invention has here been described in the form of examples and preferred embodiments but is not limited to these, the wording of the appended claims define possible embodiments for the skilled person in the art .

Claims

1. A method for quality inspection of through radiated security elements (16, 22) , security marks and areas in the vicinity of such comprised in valuable documents, by image processing analysis via computer means for the determination of its quality, characterised in that a mark (16, 22) is through radiated, whereby the radiation passing the mark is registered by means of digital means for receiving transmitted radiation.
2. A method according to claim 1, characterised in the step: correction of the weight per unit of area of the valuable document by an average value of the same.
3. A method according to claim 1, characterised in the step: determination of statistics for different values by analysing the mark, if it is a reference mark (22) , in comparison with an original mark, design mark (18) , whereby the statistics is used for quality check of test marks (16) .
4. A method according to claim 1, characterised in the step: storing of produced statistics for the reference mark (22) and of the reference mark per se (22) .
5. A method according to claim 1, characterised in the step: correction of the size of the reference mark or test mark (16) according to the original (18) and digital cutting of the image of the mark to original size.
6. A method according to claim 1, characterised in the step: checking the radiation permeability of the test mark (16) in comparison with a threshold for the same in said statistics .
7. A method according to claim 1, characterised in the step: rejection of the quality of the test mark (16) if the radiation permeability is less than the threshold value, whereby the quality, check is interrupted.
8. A method according to claim 1, characterised in the step: digital comparison of the reference mark (22) with the test mark (16) if the radiation permeability is grater than said threshold value, whereby a mask (20) with the contour of the original mark (18) is overlapped over the mark (16) .
9. A method according to claim 1, characterised in the step: determination of differences in the radiation transmittance between the reference mark (22) and the test mark (16) within the mask (20) for defined areas of the marks (16, 22) where the difference is pronounced in comparison with acceptable statistics for acceptable differences.
10. A method according to claim 1, characterised in the step: statistical determination of differences between the reference mark (22) and the test mark (16) by comparison of the same with said produced statistics for quality determination of the test mark (16) in said areas.
11. A method according to claim 1, characterised in the step: determining if the test mark (16) has approved quality from a predetermined threshold level for differences in the statistics between the reference mark (22) and the test mark (16) .
12. A method according to claim 1, characterised in the step: communication of said differences in the statistics and possible acceptance or rejection of the quality of the mark.
13. A method according to claim 1, characterised in that rejection of the quality of the mark (16) is performed if its average value of weight per unit of area in the valuable document exceeds a maximum threshold value for the average value according to said predetermined statistics .
14. A method according to claim 1, characterised in that rejection of the quality of the mark is performed if its average value of weight per unit of area in the valuable document is below a minimum threshold value for the average value according to said predetermined statistics .
15. A method according to claim 1, characterised in that rejection of the quality of the mark is performed if its rotation in relation to said mask (20) exceeds a predetermined rotation threshold value in degrees according to said predetermined statistics.
16. A method according to claim 13, characterised in that rejection of the quality of the mark is performed if its rotation in relation to said mask (20) exceeds a predetermined rotation threshold value in degrees according to said predetermined statistics in combination with said maximum threshold value .
17. A method according to claim 14, characterised in that rejection of the quality of the mark is performed if its rotation in relation to said mask (20) exceeds a predetermined rotation threshold value in degrees according to said predetermined statistics in combination with said minimum threshold value.
18. A method according to claim 1 , characterised in that rejection of the quality of the mark is performed if the shrinking factor of a mark differs in relation to the predetermined statistics.
19. A method according to claim 13-18, characterised in that rejection of the quality of the mark is performed if the shrinking factor of a mark differs in relation to the predetermined statistics in combination with said statistics for other values and/or factors .
20. A method according to 1-19, characterised in that the statistics is used for checking the distance between marks in a row of valuable paper at manufacturing thereof in a machine for this purpose*.
21. A method according to claim 20, characterised in that the statistics is used for checking the distance between marks in a row of valuable paper in the so-called machine direction.
22. A method according to claim 20, characterised in that the statistics is used for checking the distance between marks in a row of valuable paper cross wise the machine direction to the row in front .
23. A method according to claim 1-20, characterised in that the statistics is used for checking the distance between marks in a row of valuable paper in the so called machine direction and cross wise the machine direction to the row in front .
24. A method according to claim 1-23, characterised in that the mark is a watermark.
25. A method according to claim 1-24, characterised in that the mark is analysed for at least two different wavelengths of light so that at least two formation indexes is obtained for statistical determination of a quality of a mark.
26. A method according to claim 1-25, characterised in that statistics is produced when a reference mark is registered, whereby a mark to be tested immediately may be registered for quality determination with the statistics for the reference mark.
27. A device for quality inspection of through radiated security elements, security marks and areas in the vicinity of such comprised in valuable documents by image processing analysis via computer means for the determination of its quality, characterised in means for the through radiation of a reference mark (22) or a test mark (16) , whereby passing radiation is registered by digital means for receiving incident radiation, which means is connected or connectable to the computer means for analysing of a quality of a test mark (16) .
28. A method according to claim 27, characterised in correction means for the average value of weight per unit of. area of the valuable document and of the size of the reference mark or test mark (16, 22) according to the original (18) .
29. A method according to claim 27, characterised in digital cutting means for cutting the image of the mark to the size of the original .
30. A method according to claim 27, characterised in analysis means for determination of statistics for different values by analysis of the mark, if it is a reference mark (22) , compared to an original, design mark (18) , whereby the statistics are used for quality check of test marks (16) .
31. A method according to claim 27, characterised in digital storing means for produced statistics for the reference mark (22) and of the reference mark (22) per se.
32. A method according to claim 27, characterised in checking means for checking the radiation permeability of the test mark (16) in comparison with a determined threshold for the same in said statistics.
33. A method according to claim 27, characterised in rejection communication means for the quality of the test mark (16) if the radiation permeability is less than the threshold value, whereby the quality check is interrupted with communication of the quality.
34. A method according to claim 27, characterised in digital comparison means for comparison of the test mark (16) with the reference mark (22) if the radiation permeability is greater than said threshold value, whereby a mask (20) with the contour of the original mark is overlapped over the test mark (16) .
35. A method according to claim 27, characterised in determination means for determination of differences in the radiation transmittance between the reference mark (22) and the test mark (16) within the mask (20) for defined areas of the mark (16, 22) where the difference is pronounced in comparison with statistics over acceptable differences.
36. A method according to claim 27, characterised in statistical means for calculation of the difference and for comparison of the same with said statistics for quality determination of the test mark (16) in said area.
37. A method according to claim 27, characterised in determination means for determining if the mark is approved from a predetermined threshold level for differences in the statistics.
38. A method according to claim 27, characterised in communication means for communication of said differences in the statistics and possible acceptance or rejection of the quality of the test mark (16) .
39. A method according to claim 27, characterised in that rejection of the quality of the mark is performed if its average value of weight per unit of area in the valuable document exceeds a maximum threshold value for the average value according to said predetermined statistics .
40. A method according to claim 27, characterised in that rejection of the quality of the mark is performed if its average value of weight per unit of area in the valuable document is less than a minimum threshold value for the average value according to said predetermined statistics.
41. A method according to claim 27, characterised in that rejection of the quality of the mark is performed if its rotation in relation to said mask (20) exceeds a predetermined rotation threshold value in degrees according to said predetermined statistics.
42. A method according to claim 27, characterised in that rejection of the quality of the mark is performed if its rotation in relation to said mask (20) exceeds a predetermined rotation threshold value in degrees according to said predetermined statistics in combination with said maximum threshold value .
43. A method according to claim 27, characterised in that rejection of the quality of the mark is performed if its rotation in relation to said mask (20) exceeds a predetermined rotation threshold value in degrees according to said predetermined statistics in combination with said minimum threshold value .
44. A method according to claim 27, characterised in that rejection of the quality of the mark is performed if the shrinking factor differs from the predetermined statistics.
45. A method according to claim 29-43, characterised in that rejection of the quality of the mark is performed if the shrinking factor differs from the predetermined statistics in combination with said statistics for other values and/or factors.
46. A method according to claim 27-45, characterised in that the statistics are used to check the distance between marks in a row of valuable papers at manufacturing thereof in a machine for this purpose.
47. A method according to claim 46, characterised in that the statistics are used to check the distance between marks in a row of valuable papers in the so called machine direction.
48. A method according to claim 46, characterised in that the statistics are used to check the distance between marks in a row of valuable papers cross wise the machine direction to the row in f ont .
49. A method according to claim 27-45, characterised in that the statistics are used to check the distance between marks in a row of valuable papers in the so called machine direction and cross wise the machine direction to the row in front .
50. A method according to claim 27-49, characterised in that the mark is a watermark.
51. A method according to claim 27-50,. characterised in that the mark is analysed for at least two different wavelengths of light so that at least two formation indexes is obtained for statistical determination of a quality of a mark.
52. A method according to claim 27-51, characterised in that statistics are produced when a reference mark is registered, whereby a mark to be tested immediately may be registered for quality determination by the statistics for the reference mark.
PCT/SE2001/001077 2000-05-16 2001-05-15 Method and device WO2001088860A1 (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
AU2001260894A AU2001260894A1 (en) 2000-05-16 2001-05-15 Method and device

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
SE0001795-4 2000-05-16
SE0001795A SE516421C2 (en) 2000-05-16 2000-05-16 Method and apparatus for quality inspection of light-transparent safety elements

Publications (2)

Publication Number Publication Date
WO2001088860A1 true WO2001088860A1 (en) 2001-11-22
WO2001088860B1 WO2001088860B1 (en) 2002-02-28

Family

ID=20279680

Family Applications (1)

Application Number Title Priority Date Filing Date
PCT/SE2001/001077 WO2001088860A1 (en) 2000-05-16 2001-05-15 Method and device

Country Status (3)

Country Link
AU (1) AU2001260894A1 (en)
SE (1) SE516421C2 (en)
WO (1) WO2001088860A1 (en)

Cited By (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2003077187A1 (en) 2002-03-11 2003-09-18 Digital Verification Ltd. Currency verification
SG115627A1 (en) * 2003-03-12 2005-10-28 Omron Tateisi Electronics Co Value medium processor
WO2008149051A1 (en) 2007-06-06 2008-12-11 De La Rue International Limited Apparatus for analysing a security document
US8464875B2 (en) 2007-06-06 2013-06-18 De La Rue International Limited Apparatus for analysing a security document

Citations (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US5729623A (en) * 1993-10-18 1998-03-17 Glory Kogyo Kabushiki Kaisha Pattern recognition apparatus and method of optimizing mask for pattern recognition according to genetic algorithm
EP0867842A1 (en) * 1997-03-28 1998-09-30 G.D Societa' Per Azioni Method and device for controlling valuable or security items, in particular banknotes
EP0881603A1 (en) * 1996-01-25 1998-12-02 SANYO ELECTRIC Co., Ltd. Judging method of sheets, notes, etc. for forgery, and judging method of insertion direction of them
JPH1198344A (en) * 1997-09-19 1999-04-09 Mitsubishi Electric Corp Method and device for discriminating fraudulent alteration of digital image by using electronic watermark
US5915518A (en) * 1994-01-04 1999-06-29 Mars, Incorporated Detection of counterfeit objects, for instance counterfeit banknotes
US5947255A (en) * 1996-04-15 1999-09-07 Glory Kogyo Kabushiki Kaisha Method of discriminating paper notes
JPH11351962A (en) * 1998-06-12 1999-12-24 Fuji Electric Co Ltd Optical density detector for sheet and the like media

Patent Citations (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US5729623A (en) * 1993-10-18 1998-03-17 Glory Kogyo Kabushiki Kaisha Pattern recognition apparatus and method of optimizing mask for pattern recognition according to genetic algorithm
US5915518A (en) * 1994-01-04 1999-06-29 Mars, Incorporated Detection of counterfeit objects, for instance counterfeit banknotes
EP0881603A1 (en) * 1996-01-25 1998-12-02 SANYO ELECTRIC Co., Ltd. Judging method of sheets, notes, etc. for forgery, and judging method of insertion direction of them
US5947255A (en) * 1996-04-15 1999-09-07 Glory Kogyo Kabushiki Kaisha Method of discriminating paper notes
EP0867842A1 (en) * 1997-03-28 1998-09-30 G.D Societa' Per Azioni Method and device for controlling valuable or security items, in particular banknotes
JPH1198344A (en) * 1997-09-19 1999-04-09 Mitsubishi Electric Corp Method and device for discriminating fraudulent alteration of digital image by using electronic watermark
JPH11351962A (en) * 1998-06-12 1999-12-24 Fuji Electric Co Ltd Optical density detector for sheet and the like media

Non-Patent Citations (1)

* Cited by examiner, † Cited by third party
Title
PATENT ABSTRACTS OF JAPAN *

Cited By (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2003077187A1 (en) 2002-03-11 2003-09-18 Digital Verification Ltd. Currency verification
EP1490828A1 (en) * 2002-03-11 2004-12-29 Digital Verification Ltd. Currency verification
EP1490828A4 (en) * 2002-03-11 2006-09-13 Digital Verification Ltd Currency verification
SG115627A1 (en) * 2003-03-12 2005-10-28 Omron Tateisi Electronics Co Value medium processor
WO2008149051A1 (en) 2007-06-06 2008-12-11 De La Rue International Limited Apparatus for analysing a security document
US8464875B2 (en) 2007-06-06 2013-06-18 De La Rue International Limited Apparatus for analysing a security document
US8472676B2 (en) 2007-06-06 2013-06-25 De La Rue International Limited Apparatus and method for analysing a security document

Also Published As

Publication number Publication date
AU2001260894A1 (en) 2001-11-26
WO2001088860B1 (en) 2002-02-28
SE0001795L (en) 2001-11-17
SE0001795D0 (en) 2000-05-16
SE516421C2 (en) 2002-01-15

Similar Documents

Publication Publication Date Title
US4307899A (en) Identification card with hallmarks adapted to be inspected by transmitted and incident light and a process for the production thereof
JP7269177B2 (en) Authentication methods for security documents and security documents, devices and security elements
US4210346A (en) Protected document bearing watermark and method of making
DE69738115T2 (en) Security documents with built-in authentication means
CA1335509C (en) Security device
EP1864825B1 (en) Printed product, method and device for detecting such printed product, and authentication method and device
US5199744A (en) Security device
EP0388090B1 (en) Sheet with security device
RU2099197C1 (en) Printed article with latent image and method of its production (variants)
US7243952B2 (en) Authenticatable printed matter, and method for producing the same
EP1983473B1 (en) Data carrier with codes
JP2002536202A (en) Substrate for printing
EP1815443A2 (en) Value documents production and checking of value documents
WO2004013817A2 (en) Device and document for processing security documents
CN108780594A (en) Identification device, recognition methods, recognizer and the computer-readable medium comprising recognizer
CA2359029A1 (en) Printing of security documents
DE112007002714T5 (en) Method for protecting security documents against counterfeiting
WO2021048539A1 (en) Manufacture of a security device
GB2076337A (en) Identification cards
DE102005013962B4 (en) Document paper with printed security element and method for creating forgery-proof documents
WO2001088860A1 (en) Method and device
JP2008224557A (en) Inspection method and inspection device of infrared absorption print area printed in infrared absorption ink
CA2171891C (en) Method for automatic evaluation by means of an otpo-electronic device
CA1070731A (en) Technique for circumventing document coyping
JP4288998B2 (en) Paper authentication method

Legal Events

Date Code Title Description
AK Designated states

Kind code of ref document: A1

Designated state(s): AE AG AL AM AT AU AZ BA BB BG BR BY BZ CA CH CN CO CR CU CZ DE DK DM DZ EC EE ES FI GB GD GE GH GM HR HU ID IL IN IS JP KE KG KP KR KZ LC LK LR LS LT LU LV MA MD MG MK MN MW MX MZ NO NZ PL PT RO RU SD SE SG SI SK SL TJ TM TR TT TZ UA UG US UZ VN YU ZA ZW

AL Designated countries for regional patents

Kind code of ref document: A1

Designated state(s): GH GM KE LS MW MZ SD SL SZ TZ UG ZW AM AZ BY KG KZ MD RU TJ TM AT BE CH CY DE DK ES FI FR GB GR IE IT LU MC NL PT SE TR BF BJ CF CG CI CM GA GN GW ML MR NE SN TD TG

121 Ep: the epo has been informed by wipo that ep was designated in this application
AK Designated states

Kind code of ref document: B1

Designated state(s): AE AG AL AM AT AU AZ BA BB BG BR BY BZ CA CH CN CO CR CU CZ DE DK DM DZ EC EE ES FI GB GD GE GH GM HR HU ID IL IN IS JP KE KG KP KR KZ LC LK LR LS LT LU LV MA MD MG MK MN MW MX MZ NO NZ PL PT RO RU SD SE SG SI SK SL TJ TM TR TT TZ UA UG US UZ VN YU ZA ZW

AL Designated countries for regional patents

Kind code of ref document: B1

Designated state(s): GH GM KE LS MW MZ SD SL SZ TZ UG ZW AM AZ BY KG KZ MD RU TJ TM AT BE CH CY DE DK ES FI FR GB GR IE IT LU MC NL PT SE TR BF BJ CF CG CI CM GA GN GW ML MR NE SN TD TG

B Later publication of amended claims
DFPE Request for preliminary examination filed prior to expiration of 19th month from priority date (pct application filed before 20040101)
122 Ep: pct application non-entry in european phase
NENP Non-entry into the national phase

Ref country code: JP