Apparatus for online integrity verification of security features on identity documents

Abstract

The present invention relates to a method and apparatus for online integrity verification of security features (101) on an identity document (102), the apparatus (100) comprising: an illumination unit (104) for illuminating the security features (101) on the identity document (102); an image capture unit (108) for acquiring an image (124) of at least one area of ​​the illuminated security features (101) on the identity document (102); and a processing unit (116) for processing and verifying the security features (101) on the identity document (102) based on the acquired image (124); wherein the illumination unit (104) includes an infrared light source (106) for illuminating the security features (101) on the identity document (102) with infrared light.

Description

Technical Field

[0001] The present invention relates to an apparatus and method for verifying security features on an identity document, and an automatic inspection unit including an apparatus for verifying an identity document. Background Technology

[0002] A common security feature of identification documents, such as passports, is the image or photograph of the passport holder—an image of the face on the passport. These images can be placed on a metal surface of the identification document, which has a micro-periodic structure that creates an angle-dependent, highly reflective surface. This metal surface can be placed inside the document during polycarbonate lamination to create the data page of the passport or ID card. The image is laser-engraved and contains color information. Angle-dependent features may exist on the document, particularly diffractive optical variable imaging devices (DOVIDs). Furthermore, grids may be present on these angle-dependent images.

[0003] After identity documents are personalized, it is expected that the correct image has been printed on the correct document. This is done by shape matching of the person in the reference image in the database with the person in the image captured by the camera on the already produced identity document (such as a passport).

[0004] Only at a specific angle between the incident light and the observer can the true colors and correct contrast of the personalized image in the patch be seen. Only by using visible light at this precise angle can an identification image be acquired that can be used for subsequent automated integrity checks in personalization devices for identity documents such as passports or cards. Due to the highly reflective surface and the angle-dependent visualization characteristics of the personalized image, implementing online integrity checks of this feature in a robust and flexible manner is challenging.

[0005] Furthermore, the surface of security features on identification documents may have a grid, which can interfere with the quality of the acquired image. Additionally, image contrast is sensitive to the positional variations of the features within the document, highly angle-dependent, and sensitive to hardware deviations and other factors such as external white light illumination / reflection (e.g., light from the ceiling). Moreover, current methods are not flexible enough to accommodate the position of the security patch within the document layout, as the angle-dependent visualization makes certain locations difficult to implement in online inspections on production machines.

[0006] For shape matching, such images provide low scores and are difficult to distinguish from incorrect images, such as those with similar appearances. This results in poor shape matching scores when the acquired image is compared to a reference image. Summary of the Invention

[0007] Therefore, the object of the present invention is to provide an apparatus and method for verifying identity documents, capable of providing high-resolution images of security patches, and applicable to automatic inspection units, particularly in online inspections that perform shape matching between images on the document and reference images in a database.

[0008] This problem is solved by the apparatus for online integrity verification of security features on identity documents as described in the independent product claim and by the method described in the independent method claim.

[0009] The problem is addressed in particular by an apparatus for online integrity verification of security features (preferably, highly reflective security features, such as angle-dependent photographs with holder color information) on identity documents, the apparatus comprising:

[0010] - Illumination unit, used to illuminate at least the security features on the identification document;

[0011] - An image capture unit, configured to acquire an image of at least one area of ​​a security feature on an illuminated identity document; and

[0012] - Processing unit, used to process and verify the security features on the identity document based on the acquired image;

[0013] The lighting unit includes an infrared light source used to illuminate the desired area of ​​the security features on the identification document using infrared light.

[0014] An apparatus for performing online integrity verification refers to an apparatus configured to automatically check the correct production of security features (i.e., the correct image being placed on the correct identity document) during the personalization process of an identity document. This apparatus is preferably configured for online use during the production process of security features on the identity document. Therefore, the apparatus can be a workstation in an online process for producing and verifying the correct production and placement of security features on an identity document.

[0015] Security features are preferably personalized, highly reflective security features, such as angle-dependent photographs with color information of the holder. These security features (e.g., photographs of passport holders) are preferably placed on the metal surface of the identification document, which has a micro-periodic structure, creating an angle-dependent, highly reflective surface. Preferably, the RGB matrix is ​​laser-processed to engrave points in specific RGB areas or ablate material from those areas, thereby determining the color of specific points. Therefore, the feature (e.g., the image) is preferably laser-engraved and / or laser-ablated and has color information. Preferably, angle-dependent features are present on the document, particularly diffractive optical variable imaging devices (DOVID). Most preferably, the image is laser-engraved with color information and further utilizes DOVID technology, i.e., including, for example, a color portrait embedded in DOVID. Furthermore, these angle-dependent images preferably have a grid pattern.

[0016] An identification document (ID) is a credential used to identify an owner. An ID can be any document used to prove an individual's identity. Preferably, an identification document is an identity card (IC card, ID card, resident card) or passport card. Sometimes, a driver's license can also serve as an identification document. Furthermore, it can also be an ID access pass.

[0017] An illumination unit for illuminating at least the security feature or a portion thereof on an identification document is part of a device for illuminating a specific area of ​​the ID (particularly the security feature on the ID). Preferably, an area larger than the ID may also be illuminated. The illumination device preferably includes a light source. The light source may include light sources in the UV, VIS, NIR, IR, and THz spectral regions, or combinations thereof, and at least, and most preferably, an infrared light source for illuminating the security feature on the identification document using infrared light.

[0018] Furthermore, the illumination unit preferably includes optical elements for guiding light from the light source to the desired area. Such optical elements preferably include mirrors, filters, polarizers, scanners, beam shift optics (such as trimmers), prisms, diffraction gratings, diffusers, lenses, or combinations thereof.

[0019] The image capture unit, used to acquire an image of at least one area of ​​the illuminated security feature on an identification document, is the part of the device used to capture an image of the security feature (e.g., a photograph on a passport). Preferably, at least one area of ​​the document is the area where the security feature is located. Preferably, the entire ID or even an area larger than the ID can also be captured. Therefore, a wider area can be used to place the ID, and the requirement for ID alignment is not strict. The image capture unit preferably includes a camera. Furthermore, the image capture unit preferably includes optical elements for guiding light from the security feature to the camera. Such optical elements preferably include mirrors, filters, polarizers, scanners, beam shift optics (such as trimmers), prisms, diffraction gratings, diffusers, lenses, or combinations thereof.

[0020] The processing unit preferably includes a processor and a graphics card. Preferably, the processing unit includes a computer. The processing unit is adapted to process information collected by the image capture unit, preferably image information from the acquired image. The processing unit preferably includes negative-to-positive conversion applications, color inversion applications, brightness adjustment applications, contrast adjustment applications, or combinations thereof. Furthermore, the processing unit preferably includes a storage unit for storing data related to the acquired image and data of the enhanced acquired image (i.e., the image derived from the acquired image after processing by the processing unit).

[0021] By capturing images of security features on the ID and processing the acquired images, artifacts in the enhanced images are reduced.

[0022] Furthermore, the processing unit is adapted to verify security features on an ID card based on the acquired image. The main purpose of this verification or check is to (a) check whether the ID contains the correct person or the correct sign, text, number, or image, or a combination thereof, and (b) whether the quality of the engraved image exceeds a predetermined threshold. Preferably, this is accomplished by comparing the enhanced image with the original image that was initially used as the basis for the security features (e.g., comparing the acquired image with a reference image in a database intended to be placed on the ID card). Preferably, the comparison includes shape matching of the person or sign. Most preferably, the processing unit derives parameters from the two images (the enhanced image and the reference image) and compares these parameters. If a match exists (i.e., some parameters in both images are found to be higher than a predetermined threshold by a certain percentage), the processing unit concludes that the images are identical and the security features on the ID are verified. Further, a threshold can be set to identify whether the acquired image is excessively blurry, only partially visible (less than 20% of the image), etc. If the threshold is not met, the processing unit concludes that the images are not identical and the security features on the ID are not verified.

[0023] By using an infrared light source to illuminate the security features on an ID card, the captured image loses color information. Furthermore, because the engraving of the RGB pattern creates holes in these areas, infrared illumination helps obtain a more reliable, angle-independent image. By using infrared illumination, only a portion of the engraved metallized patch in at least one area reflects infrared light, which improves the quality of the acquired image and image capture. Therefore, this technology enables the processing unit to perform more reliable processing when verifying security features on ID cards based on the acquired image, especially in shape matching, where the lines constituting the image have many gaps, leading to less reliable verification.

[0024] According to one embodiment, the infrared light source is a dark-field illuminated infrared light source. The dark-field illuminated infrared light source further improves the reflection of light on the aforementioned engraved portion of the identity document, and thus improves the quality of the acquired image and further reduces artifacts in the acquired image, thereby further improving document verification.

[0025] In one embodiment, the image capture unit includes a camera and at least one lens to acquire images, wherein the camera includes a field of view covering the entire ID document. This embodiment also improves the quality of the acquired images. Furthermore, due to infrared light and the camera's field of view, the image to be acquired can be placed anywhere on the ID document without the risk of quality loss.

[0026] Alternatively, the camera and at least one lens are configured to filter out other security elements placed on top of the security feature, such as embossing or tactile features, as well as artifacts, such as the grid in at least one area of ​​an identification document. To filter out these other security elements, the camera and at least one lens preferably have a lower spatial resolution than the other security elements. In particular, the optical system has a lower resolution to avoid capturing the grid on these angle-dependent images. The camera and lens combination preferably has a spatial density (i.e., the number of pixels per millimeter in the field of view) that is approximately one time or less the minimum size of the grid (or other security element). Therefore, other security elements can be filtered out by the optical arrangement and will not appear in the acquired image.

[0027] According to another embodiment, the image capture unit is configured to acquire images independently of the viewing angle of the ID card. Since the image is generated on the ID by punching holes in the metal surface, the image capture unit preferably employs means that enhance the inhomogeneity of the metal surface and make it more visible, such as infrared dark-field technology. Due to this embodiment, image acquisition no longer depends on angle. Therefore, image acquisition is further independent of the image's position. This implementation enables the device to be used for online inspection.

[0028] However, the acquired image may be a negative image. Therefore, the processing unit is configured to process and thereby enhance the acquired image by using at least one of the following:

[0029] - Color inversion; and / or

[0030] -Negative-positive conversion;

[0031] - Brightness adjustment; and / or

[0032] - Contrast adjustment.

[0033] Security features can be a portrait of a person known in the passport. Alternatively, it can be a graphic mark (such as a company logo), or text, or numbers, or an image, or a combination thereof.

[0034] In one embodiment, the processing unit for verifying an identity document is configured to compare the enhanced image with a reference image of the identity document.

[0035] The method for verifying security features on an identity document includes the following steps:

[0036] - Illuminate at least a portion of the identification document using infrared light via an illumination unit;

[0037] - Acquire an image of at least one area of ​​the illuminated identification document via an image capture unit; and

[0038] - Optionally, the acquired image can be enhanced by processing it; and

[0039] - Based on the acquired image, especially the enhanced image, the enhanced image is compared with a reference image by the processing unit to verify the security features on the identity document.

[0040] By illuminating the ID card with infrared light via an illumination unit and then acquiring an image of at least one area of ​​the illuminated ID card, the color information of the security features is lost, and the acquired image only contains black, white, and gray information. Therefore, the contrast quality of the acquired image is higher than that in the case where color information is present.

[0041] By processing and verifying the security features of an identity document based on the acquired image via a processing unit, it can be verified whether the correct information (including images, logos, text, or numbers) has been personalized onto the correct ID in the security features. Verification is preferably performed by comparing the acquired image with a reference image. Preferably, the comparison is performed between the acquired image and the reference image after enhancement through one or more processing steps to improve the quality of the acquired image. Therefore, enhancement steps are preferred. The reference image is the original image used to generate the security features. It is preferably stored in the processor or database of the production device.

[0042] The processing steps can utilize the means described in the product-related context. Preferably, the method is performed by the aforementioned device for verifying identification documents.

[0043] According to one embodiment, the method further includes the following steps:

[0044] - Obtain images independently of the perspective of the identification document.

[0045] This can be achieved, for example, by capturing images using infrared technology. Specifically, using dark-field infrared light, only the surface of the document, independent of angle, returns information. This could be, for instance, a hole in a metal surface—the larger the hole, the brighter the information in the captured image, while the dark areas in the acquired image correspond to the entire metal surface or the DOVID or RGB matrix, because this reflection is not captured by the camera due to the use of dark-field technology. Therefore, no reflective surface has a negative impact, and there is more freedom in locating the ID when capturing the image, allowing security features to exist anywhere on the document without adjusting or realigning the device. Thus, a system robust to different document layouts and insensitive to misalignment is provided.

[0046] In another embodiment, the method further includes the following steps:

[0047] - The acquired image is processed using at least one of the following:

[0048] - Invert colors; and / or

[0049] - Convert negative film to positive film, and vice versa; and / or

[0050] - Adjust brightness; and / or

[0051] - Adjust the contrast.

[0052] These different processing applications can enhance the quality of the acquired image and make it more reliably comparable to a reference image.

[0053] Furthermore, this invention also discloses and claims an automatic verification unit. This automatic verification unit includes the means for verifying identity documents as described above, particularly for online use during the ID personalization process. Attached Figure Description

[0054] Further preferred features and / or advantages of the present invention are also reflected in the subject matter of the following description of the accompanying drawings:

[0055] Figure 1 This is a schematic illustration of a device for verifying identity documents according to the present invention;

[0056] Figure 2 This is an illustrative comparison between processing images according to existing technology and according to the present invention.

[0057] In the accompanying drawings, the same parts are always indicated by the same reference numerals. Detailed Implementation

[0058] Figure 1 A schematic illustration of a device 100 for verifying an identity document 102 having security feature 101 is shown. For better illustration, security feature 101 is schematically shown at a higher level on the identity document 102. Security feature 101 is preferably embedded in a layer of the identity document 102. Preferably, both security feature 101 and identity document 102 have a laminate cover (not shown).

[0059] Device 100 includes an illumination unit 104 for illuminating an identification document 102. The identification document 102 may be a passport, driver's license, or any other ID card or access authorization card. The identification document 102 bears a security feature 101 in the form of a photograph of a person.

[0060] The illumination unit 104 includes a method for using infrared (IR) light L IR Infrared light source 106 illuminates the identification document. Preferably, infrared light source 106 is a dark-field illumination infrared light source.

[0061] In addition, the device 100 includes an image capture unit 108 for acquiring an image of at least one area of ​​the illuminated identity document 102.

[0062] The image capture unit 108 includes a camera 110 and at least one lens 112 to acquire images. The camera 110 includes a field of view 114 covering the entire identity document 102.

[0063] In addition, the device 100 includes a processing unit 116 for processing and verifying the identity document 102 based on the acquired image.

[0064] To verify the identity document 102, the processing unit 116 is connected to the image capture unit 108 to receive the acquired image from the image capture unit 108. Then, the processing unit 116 enhances the acquired image. The following will combine... Figure 2 This will be described in more detail. Then, the enhanced acquired image is compared with a reference image, and it is determined whether the acquired image matches the reference image.

[0065] The aforementioned device 100 may be part of an automated inspection unit 118 for online inspection. This inspection unit 118 may be a workstation in a device for personalizing IDs by printing security features 101 onto identification documents 102.

[0066] about Figure 2 This illustrates a comparison between the verification of security features 101 on an image-based identity document 102 according to existing technology and according to the present invention.

[0067] On the left, reference image 120 is shown. The top row shows image 122, acquired using white light capture according to known techniques. It can be seen from image 122 that the quality is not very good. Comparison with reference image 120 is difficult, especially when the comparison should be automated, meaning that the comparison and verification are not performed by, for example, a human operator.

[0068] As can be seen from the next line, the first image shown was captured by the image capture unit 108 using infrared light L. IR 124 captured images.

[0069] Although the acquired image 124 is a negative image, its quality is much better than that of image 122 acquired according to the prior art.

[0070] Since the acquired image 124 is a negative, the processing unit 116 performs color inversion on the acquired image 124 in the first step 126, or converts it from a negative to a positive image if it is a black and white image, and vice versa. This produces an enhanced acquired image with inverted colors and / or negative-to-positive conversion. Then, in the second step 128, the processing unit continues to enhance the acquired image 124 by adjusting its brightness and / or contrast. This produces an enhanced acquired image with adjusted brightness and / or contrast.

[0071] Following this enhancement, the acquired image 124 is ready for the verification process, namely, to compare the enhanced image with inverted colors and / or negative-to-positive conversion, and / or with adjusted brightness and / or adjusted contrast, with the reference image 120.

[0072] In summary, the present invention provides the following advantages:

[0073] - Eliminates the angle dependency of image acquisition; enables the reuse of hardware settings for security features at different locations on or within the document;

[0074] - Improve the overall contrast of the acquired image;

[0075] - Improve the quality of acquired images and the quality of personalized data within security signs, as security elements and artifacts can be filtered out; and

[0076] Provides robust, efficient, and high-quality online inspection units. List of reference numerals in the attached diagram:

[0077] 100 Devices for performing online integrity verification

[0078] 101 Safety Features

[0079] 102 ID Card

[0080] 104 lighting units

[0081] 106 Infrared Light Source

[0082] 108 image capture units

[0083] 110 camera

[0084] 112 lenses

[0085] 114 Field of view of the camera

[0086] 116 processing units

[0087] 118 Automatic Inspection Unit

[0088] 120 Reference Images

[0089] 122 Images acquired using white light

[0090] 124 Images acquired using infrared light

[0091] 126 Images acquired after enhancement with color inversion and / or negative-to-positive conversion.

[0092] 128 Images acquired after enhancement with adjusted brightness and / or contrast.

[0093] L IR Infrared light

Claims

1. An apparatus (100) for online integrity verification of a security feature (101) on an identity document (102), the apparatus (100) comprising: - Illumination unit (104), the illumination unit (104) is used to illuminate the security feature (101) on the identity document (102); - Image capture unit (108), the image capture unit (108) being used to acquire an image (124) of at least one area of ​​the illuminated security feature (101) on the identity document (102); and - Processing unit (116), the processing unit (116) is used to process and verify the security feature (101) on the identity document (102) based on the acquired image (124); The lighting unit (104) includes an infrared light source (106), which is used to illuminate the security feature (101) on the identity document (102) with infrared light.

2. The apparatus (100) according to claim 1, wherein The infrared light source (106) is a dark field illumination infrared light source.

3. The apparatus (100) according to claim 1 or 2, wherein The image capture unit (108) includes a camera (110) and at least one lens (112) to acquire the image (124), wherein the camera (110) includes the entire field of view of the identity document (102).

4. The apparatus (100) according to claim 3, wherein The camera (110) and the at least one lens (112) are configured to filter out security elements and / or artifacts on at least one area of ​​the identity document (102).

5. The apparatus (100) according to any one of claims 1 to 4, wherein, The image capture unit (108) is configured to acquire the image (124) independently of the viewpoint of the ID card (102).

6. The apparatus (100) according to any one of claims 1 to 5, wherein, The processing unit (116) is configured to process the acquired image (124) by using at least one of the following: - Color inversion; and / or -Negative-positive conversion; and / or - Brightness adjustment; and / or - Contrast adjustment.

7. The apparatus (100) according to any one of the preceding claims, wherein, The processing unit (116) for verifying the identity document (102) is configured to compare a reference image (120) with an image (124) obtained from the security feature (101) on the identity document (102).

8. The apparatus (100) according to any one of the preceding claims, wherein, The identification document (102) is at least one of the following: -passport; - Driver's license; and / or -ID document access pass.

9. A method for verifying a security feature (101) on an identity document (102), the method comprising the steps of: -At least a portion of the identity document (102) is illuminated by infrared light via the illumination unit (104); - Acquire an image (124) of at least one area of ​​the illuminated identity document (102) via the image capture unit (108); and - Optionally, the acquired image (124) can be enhanced by processing the acquired image (124); and -Based on the acquired image (124), especially the enhanced acquired image (126, 128) obtained by comparing the acquired image (124, 126, 128) with the reference image (120) via the processing unit (116), the security feature (101) on the identity document (102) is verified.

10. The method of claim 9, further comprising the step of: - The image (124) is acquired independently of the perspective of the identity document (102).

11. The method according to claim 9 or 10, further comprising the step of: The acquired image (124) is processed by using at least one of the following: - Invert colors; and / or - Convert negatives to positives and vice versa; and / or - Adjust brightness; and / or - Adjust the contrast.

12. An automatic inspection unit, the automatic inspection unit comprising the apparatus (100) according to any one of claims 1 to 8.

Images