Abstract:
An examination apparatus examines an item including a person or a container and has a determination unit for determining a relevance level which can be assigned to the item under examination, in particular a hazard level, and an image capture unit for capturing an image of the item under examination. The examination apparatus has a database, an automated evaluation unit for automatically evaluating at least one section of the image using the database, an evaluation unit operated by a user for the visual evaluation of a section of the image by the user, and an input unit for inputting at least one evaluation input by the user, and a database processing unit for processing the database. The database processing unit processes a database entry using the evaluation input in conjunction with the determination of the relevance level.

Description:
CROSS-REFERENCE TO RELATED APPLICATION 
     This application claims the priority, under 35 U.S.C. §119, of German application DE 10 2011 004 185.0, filed Feb. 16, 2011; the prior application is herewith incorporated by reference in its entirety. 
     FIELD OF THE INVENTION 
     The invention is based on an examination apparatus for examining an item under examination in the form of a person and/or a container, having a determination unit which is intended to determine a relevance level which can be assigned to the item under examination, in particular a hazard level and an image capture unit for capturing an image of the item under examination. The examination apparatus further has a database, an automated evaluation unit which is intended to automatically evaluate at least one section of the image using the database, an evaluation unit which can be operated by a user and is intended for the visual evaluation of at least one section of the image by the user, an input unit which is intended for the input of at least one evaluation input by the user, and a database processing unit for processing the database. 
     U.S. patent disclosure No. 2007/0041613 A1 discloses an examination apparatus of the generic type. The latter is intended to examine containers which potentially comprise items which jeopardize safety, for example weapons. The apparatus has an image capture unit which captures an image of the container contents. This image is evaluated by an image evaluation unit using an object database for recognizing hazardous objects. The examination apparatus also contains a further evaluation unit having a user interface in the form of an operator interface which can be used by the user to visually evaluate the recorded image. In order to process the object database, in particular to supplement the object database, a previously known object which corresponds to a certain hazard level is captured by the image capture unit outside normal operation of the examination apparatus. In this case, images of the object, in particular in different orientations, are recorded and are used as new database entries for subsequent evaluation operations. 
     SUMMARY OF THE INVENTION 
     On the basis of this prior art, the invention is based on the object of providing an examination apparatus of the generic type in which automation in the determination of the relevance level can be quickly and efficiently optimized. 
     The object is achieved by virtue of the fact that the database processing unit is intended to process at least one database entry using the evaluation input in conjunction with the determination of the relevance level. As a result, a user input which is conventionally input by the user anyway when visually evaluating the image can be advantageously used to optimize automatic determination of the relevance level. 
     The evaluation input by the user can be made, in particular, on the basis of evaluation of the image which is carried out by the automated evaluation unit. During this evaluation, the automated evaluation unit preferably attempts to assign a reference item to the image using the database, the recognition of which reference item in the item under examination corresponds to a particular relevance level, for example a low or high risk. For this purpose, assignments of image data to such reference items are advantageously entered in the database. 
     For example, the evaluation input may be a confirmation or rejection of such an automatic assignment. In addition, the evaluation input may correspond to a confidence parameter which is assigned to the automatic assignment. The evaluation input may also be an input on the basis of a lack of an automatic assignment, in particular relating to a reference item which is not contained in the database. 
     The database may be stored locally at the examination location. For this purpose, the examination apparatus may have a storage unit for storing the database to which the automated evaluation unit and/or the database processing unit directly has/have access. Alternatively or additionally, the database may be stored on a database server which is remote from the examination location and can be accessed via a data network. For this purpose, the examination apparatus may advantageously have an interface by which the automated evaluation unit and/or the database processing unit has/have access to the database via the data network. 
     Processing which is carried out “in conjunction with the determination of the relevance level” is intended to be understood as meaning processing using data which originate from the determination of the relevance level for the item under examination which is currently being examined by the examination apparatus and has at least partially unknown, and conventionally completely unknown, contents before the start of the examination. These data are obtained under the real conditions of normal operation of the examination apparatus, in which a series of persons or containers is typically examined. As a result of the fact that the database is processed in conjunction with the determination of the relevance level, evaluation inputs which originate from the examination under real conditions, that is to say conditions which have not been simulated, are advantageously taken into account, as a result of which the database can be optimally adapted to these real conditions. If the item under examination corresponds to a person to be examined, the “contents” of the item under examination are formed by objects carried on the person&#39;s body. 
     In this context, the evaluation inputs which are produced in conjunction with the determination of the relevance level can be collected or stored for subsequent processing of the database. In this case, the database can be processed using the different evaluation inputs, which were produced with respect to the determination of the relevance levels for a series of different items under examination, after the end of normal operation of the examination apparatus, in which the series was examined. 
     However, it is advantageous if the examination apparatus has an examination mode in which a series of items under examination each having at least partially unknown, and conventionally completely unknown, contents are examined, the database being processed during the examination mode. The processing of the database in conjunction with the determination of the relevance level for a particular item under examination can be at least partially carried out in this case while determining the reference level for a further item under examination in the series. However, it is preferred for the database to be processed, as far as possible, without delay after the evaluation input has been input, as a result of which the processed database can already be available for subsequent examinations of further items under examination. 
     A “relevance level” is intended to be understood as meaning, in particular, a parameter which can be assigned to the item under examination and characterizes the relevance of the item under examination with respect to further handling. In one advantageous use of the examination apparatus during a security check of travelers or transported goods, the relevance level corresponds to a hazard level with which defined safety measures for handling the item under examination are associated. The relevance level can be alternatively or additionally associated with the detection of objects or substances which are not an immediate hazard but are legally prohibited, for example during the examination of freight containers by a customs authority. 
     “Processing” of a database entry is intended to be understood as meaning, in particular, changing, adapting, replacing and/or deleting an existing database entry. The processing of a database entry can also alternatively or additionally correspond to the generation of a new database entry using the evaluation input, as proposed in one advantageous development of the invention. This makes it possible to quickly and easily supplement the database with a new reference item. 
     In order to quickly evaluate the captured image by the automated evaluation unit, the invention proposes that the database entry contains image data which are assigned to a reference item and are stored in at least one format suitable for an image recognition method. In a particularly advantageous manner, the format corresponds to a vector format, as a result of which a recognition operation taking place using these image data can be carried out independently of the orientation of objects inside the image. 
     One preferred embodiment of the invention proposes that the database processing unit is intended to process the image data relating to the database entry using at least one region of the image evaluated by the user. In this case, a region of the visually evaluated image corresponding to at least one section of the image captured by the image capture unit, which region is selected by the user, is expediently taken into account when processing the database entry. This region can be advantageously selected by the user on the basis of good distinctiveness, as a result of which the image region which, after the database entry has been processed, is stored in the database entry in the form of image data can be identified by the automated evaluation unit in images of further items under examination. 
     It is also proposed that the database entry contains a confidence parameter which affects the assignment to the reference item. The confidence parameter advantageously has the function of a quality parameter which characterizes the recognition strength of the stored image data with respect to a particular reference item. 
     In this context, one development of the invention proposes that a threshold value of the confidence parameter is defined, the threshold value constituting a prerequisite for automatic determination of the relevance level using the automated evaluation unit. The confidence parameter is preferably defined in such a manner that it increases with increasing recognition strength of the image data. If the threshold value has not been reached, that is to say the confidence parameter is less than the threshold value, the image is preferably, as an alternative or in addition to the automated evaluation, visually evaluated using the evaluation unit which can be operated by the user since the recognition strength of the existing image data is not sufficient for automatic assignment. If the threshold value has been reached, the relevance level can be automatically determined by the automated evaluation unit, in which case it is possible to dispense with additional visual evaluation of the image. 
     One preferred development of the invention proposes that the database processing unit is intended to change the confidence parameter using the evaluation input. This makes it possible to achieve an advantageous learning process of the automated evaluation unit, as a result of which the determination operations which are carried out by the automated evaluation unit and result in the relevance level being automatically determined without additional visual evaluation by the user can be increased. 
     The invention also proposes a method for examining an item under examination in the form of a person and/or a container. In order to determine a relevance level which can be assigned to the item under examination, an image of the item under examination is captured, at least one section of the image is automatically evaluated using a database, at least one section of the image is visually evaluated by the user, an evaluation input being input by the user, and in which the database is processed, at least one database entry being processed using the evaluation input in conjunction with the determination of the relevance level. 
     Other features which are considered as characteristic for the invention are set forth in the appended claims. 
     Although the invention is illustrated and described herein as embodied in an examination apparatus for examining an item under examination in the form of a person and/or a container, it is nevertheless not intended to be limited to the details shown, since various modifications and structural changes may be made therein without departing from the spirit of the invention and within the scope and range of equivalents of the claims. 
     The construction and method of operation of the invention, however, together with additional objects and advantages thereof will be best understood from the following description of specific embodiments when read in connection with the accompanying drawings. 
    
    
     
       BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWING 
         FIG. 1  is an illustration of an examination apparatus according to the invention having an image capture unit and an image evaluation unit as well as feed and removal conveyors in a view from above according to the invention; 
         FIG. 2  is an illustration of a detailed view of the image evaluation unit and an enlargement of a captured image; and 
         FIG. 3  is an illustration of a database of the image evaluation unit.\ 
     
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
     Referring now to the figures of the drawing in detail and first, particularly, to  FIG. 1  thereof, there is shown an examination apparatus  10  for examining items under examination  12  in the form of pieces of luggage at an airport in a highly schematic view from above. The function of the examination apparatus  10  is to assign a hazard level to an item under examination  12  by analyzing the contents of the latter. The examination is known to take place after the passenger has handed over the piece of luggage during check-in and before the piece of luggage is conveyed further to the associated aircraft. A feed conveyor  14  and a removal conveyor  16  are provided for the purpose of conveying the pieces of luggage to and from the examination apparatus  10 . In an alternative embodiment, an examination apparatus  10  which is used to examine passengers and/or their hand luggage at the conventional security checks at the airport is conceivable. 
     The examination mode of the examination apparatus  10 , in which items under examination  12  in a series are examined in succession, is explained using  FIG. 1 . Before passing through the examination apparatus  10 , the contents of the items under examination  12  are unknown or partially unknown to airport personnel. For each item under examination  12 , the hazard level which can be assigned to the item under examination  12  is determined using a determination unit  17 . 
     In order to determine the hazard level for an item under examination  12 , the latter is first of all transported to an image capture unit  18  using the feed conveyor  14 . In the exemplary embodiment under consideration, the image capture unit  18  is in the form of an X-ray scanner which generates an X-ray image B of the item under examination  12 , in particular the contents of the latter. Further designs of the image capture unit  18  which allow image capture of the contents of an item under examination  12  without manual examination, for example in the form of a scanner which operates using terahertz radiation, are likewise possible. 
     In order to evaluate the image B, the examination apparatus  10  has a first image evaluation unit  20  which is intended to automatically evaluate the image B, to be precise is intended to automatically recognize a hazardous item in the item under examination  12 , in particular. For this purpose, the image evaluation unit  20 , which is illustrated in more detail in a detailed view in  FIG. 2 , is operatively connected to the image capture unit  18 . The image evaluation unit  20  is provided with a computation unit  22  ( FIG. 2 ) which evaluates the image B captured by the image capture unit  18  using image recognition software. For this purpose, use is made of data from a database DB which stores assignments of prestored image data BD to reference items G ( FIG. 3 ) which are potentially in the items under examination  12  and constitute a hazard or conversely correspond to harmless items. When evaluating the image B, the computation unit  22  compares the image B with the stored image data BD in the database DB, the attempt to recognize one of the reference items G in the item under examination  12  being carried out in a fully automatic manner, that is to say without visual evaluation by a user  24  and/or without an input by the user  24 . 
     The database DB is stored in a storage unit  26 , the evaluation unit  20 , to be precise its computation unit  22  in particular, being operatively connected to the storage unit  26 . Alternatively or additionally, the database DB may be stored on a database server which is remote from the examination location and is not illustrated in the figure, the evaluation unit  20  having access to this database server by an interface via a data network. 
     The determination unit  17  also has a second evaluation unit  28  which is operated by the user  24 . The second evaluation unit  28  enables visual evaluation of the image B by the user  24  and contains, for this purpose, a display unit  30  which displays the image B to the user  24 . The evaluation unit  28  is provided with a computation unit  32  which makes it possible for the user  24  to process the image B, in particular to magnify the image B and/or to extract a suspicious region from the image B. The user  24  uses the image B to make a decision on the further handling of the item under examination  12 . 
     If there is no suspicion with respect to the item under examination  12 , the latter is conveyed further without further examination, the decision corresponding to a “release”. The user  24  can also decide that manual examination should be carried out in an examination station  34 , the decision corresponding to a “non-release”. In this case, the item under examination  12  is removed from the conveying flow and is manually examined. The decision made (“release” or “non-release”) and the reasons for this decision are input as an evaluation input  38  by the user  24  using an input unit  36 . 
     The user  24  can also confirm the result of the evaluation of the image B, as carried out by the automated evaluation unit  20 , by visually evaluating the image B, if the visual evaluation of the image B corresponds to the automatic evaluation, or can reject the result if the two evaluations do not correspond. This evaluation input  38  is used to enable a learning process of the automated evaluation unit  20 . The examination apparatus  10  provides for a particular hierarchy which is used to control a decision-making authorization of the automated evaluation unit  20  relating to the hazard level, and therefore the further handling of the item under examination  12 , with respect to the visual evaluation unit  28  and is subsequently specified in more detail below. The practice of taking into account the evaluation inputs  38  input by the user  24  advantageously makes it possible to increase the number of cases in which the automated evaluation unit  20  automatically determines the hazard level in order to thus increase the autonomy of the examination apparatus  10 . 
       FIG. 3  shows a schematic view of the database DB. The latter has database entries DB. 1 , DB. 2 , . . . , DB.i etc. A database entry, for example DB. 1 , substantially corresponds to the assignment of image data, for example BD. 1 , to a respective reference item, G. 1  in this example, which corresponds to a particular hazard level. A plurality of sets of image data (for example BD. 2 , BD. 3 ) can be assigned to a reference item (for example G. 2 ). The image data BD.i are stored in a format suitable for image recognition by the computation unit  22  of the automated evaluation unit  20 , as described above. In particular, the image data BD.i are stored in a vector format. 
     The database entries DB.i also each contain a confidence parameter V.i which affects the corresponding assignment of the image data BD.i to a reference item G.j. A threshold value of the confidence parameter V, which is used to define the decision-making authorization of the automated evaluation unit  20 , is defined in the examination apparatus  10 . The threshold value constitutes a prerequisite for automatically determining the relevance level using the automated evaluation unit  20 . 
     If, for a database entry DB.i, the confidence parameter V.i is at this threshold value or above this threshold value, the automated evaluation unit  20  is authorized, when a reference item is recognized in the image B, to itself make a decision on the item under examination  12 , that is to say to determine the hazard level, without the image B being forwarded to the visual evaluation unit  28  for evaluation by the user  24 . The automated evaluation unit  28  may make a decision on the release of the item under examination  12 , which corresponds to the determination of the lowest hazard level, and/or it can automatically signal the hazard when a hazardous item is recognized in the image B, which corresponds to the determination of a higher hazard level. 
     If the confidence parameter V of an identified link to a reference item is below the threshold value or no correspondence to image data BD in the database could be determined in the image, the image B is forwarded to the evaluation unit  28  for visual evaluation by the user  24 . In the case mentioned first, the automated evaluation unit  20  cannot definitively determine the hazard level, but rather the evaluation unit  20  can inform the user  24  of a suspicion that a particular reference item is in the item under examination  12 . In this case, the user  24  is intended to use the visual evaluation unit  28  to confirm or not confirm this suspicion, this information being considered to be the evaluation input  38 . 
     The database DB can be processed using a database processing unit  40  which is part of the examination apparatus  10 . This is illustrated in  FIG. 2 . The database processing unit  40  which is operatively connected to the storage unit  26  (or to a remote database server via a data network) can be used to update the database DB by generating new database entries DB.i and/or changing or replacing existing database entries DB.i. 
     The database processing unit  40  is advantageously configured to make changes to the database DB in conjunction with the determination of the hazard level for an item under examination  12 . For this purpose, the evaluation inputs  38  by the user  24 , which originate from the determination of the hazard level for the item under examination  12  currently being examined, are taken into account. The database DB is therefore updated during the examination mode, that is to say during conventional normal operation, the evaluation inputs  38  input by the user  24  being recorded and taken into account for processing a database entry or a plurality of database entries DB.i. 
     An evaluation input  38  by the user  24  can be used to generate a new database entry DB.i. This is the case, for example, when the user  24  identifies an object in the item under examination  12  which is not contained in the database DB. The user  24  can define the object in his evaluation input  38 , that is to say can define it as a reference item G and can assign a hazard level to it. For this purpose, the user  24  can extract a region  42  of the image B (see  FIG. 2 ) which represents the object, this region  42  being used as an evaluation input  38 . In this case, the region  42  which is extracted from the image B and represents the object is linked to the new reference item G in the form of a set of image data BD, this link being stored in a new database entry. The confidence parameter V is set to a minimum value when generating a new database entry. 
     In addition, an evaluation input  38  by the user  24  can be used to change the confidence value V.i of a database entry DB.i. As already described above, the automated evaluation unit  20  can inform the visual evaluation unit  28  and thus the user  24  of a suspicion in the event of a confidence parameter V.i below the threshold value. If this suspicion is confirmed by the user  24 , the confirmation can be recorded, as an evaluation input  38 , by the database processing unit  40  which then increases the corresponding confidence value V.i by a predetermined value. If the confidence value reaches the threshold value for this database entry DB.i, the automated evaluation unit  20  can itself make a decision on the release of the item under examination  12  with respect to the corresponding reference item or the signaling of a high hazard level during subsequent examination. The practice of taking into account the evaluation input  38  therefore contributes to a learning process of the automated evaluation unit  20 . 
     The examination apparatus  10  described using the drawings is not restricted to the examination of pieces of luggage. Use of the concept according to the invention in conjunction with the examination of freight containers or passengers is likewise conceivable. In terms of use, the examination apparatus is not restricted to use in an airport either. It is likewise suitable for use in other environments, for example for use by a customs authority monitoring the import of hazardous and/or prohibited goods.