Method for evaluating security prints

0001The invention relates to a method for evaluating security imprints, in the manner specified in the preamble of claim 1. The method comprises steps for recovering individual information from the printed marking using a symmetrical encryption algorithm in order to generate the initial number again from each crypto number, and the comparison of the latter with the information openly printed on the mail piece. The graphic symbols printed on a piece of mail can be automatically entered with a suitable reading device.

0002In particular, the invention relates to franking machines that provide a fully electronic impression for franking mail, including an advertising slogan and a mark. The franking machine is equipped with at least one input means, an output means, an input / output control module, a memory for at least one advertising cliché, a control device and a printer module.

0003A franking machine generally creates an imprint in a form agreed with the post right-aligned, parallel to the upper edge of the mail item, beginning with the content of the postage in the postmark, the date in the day stamp and stamp imprints for advertising slogans and, if applicable, the type of shipment in the election print stamp. The post value, the date and the type of shipment form the variable information to be entered in accordance with the piece of mail.

0004The postage value is the transport fee paid in advance by the sender, which is taken from a refillable credit register and used to clear the mail item.

0005The date is a current date or a future date in a postmark. While the current date is automatically provided by a clock / date module, the desired future date must be set in the case of manual pre-dating. Pre-dating is interesting in all cases where the volume of mail is processed and franked very early, but has to be dispatched on a certain date. The variable dates for the date can be embedded in the daily stamp in the same way as when the postal value is printed.

0006The approved advertising clichés can contain a wide variety of messages, in particular the address, the company logo, the mailbox and / or any other message. The advertising cliché is additional information in the postal sense, which must be agreed with the postal authority.

0007It is well known that an advertising message is applied to a fixed printing block that can be replaced by the user. Such a machine provides a distinctive fingerprint. It would be pointless to copy the imprint with a modern color copier, because even if the postage value and the serial number are falsified, the unmistakable fingerprint can be used to identify the machine that is being imitated with the intention of forgery. According to a solution described in DE 38 40 041, the non-continuously changing imprints of the clichés are applied to a printing drum and the variable parts of the clichés (characteristic data) are generated electronically and printed on a thermal printer. The characteristic data are assigned to a specific place in the cliché purely mechanically.

0008As is known, the difficulty of changing advertising messages without reducing the security of fees can be solved purely mechanically by replacing individual line castings carrying a text part. However, this is too time-consuming and would lead to an interruption in printing. On the other hand, such a change would be possible much more quickly with fully electronic impactless printing processes.

0009A franking machine message printing system is already known from DE 37 12 100, the characters to be printed comprising a postage value and a remotely transmitted message. The electrical postage meter is equipped with a postage meter billing circuit which provides the postage value, with a telephone or transmission connection, with a message input device, with a transmission control system, with a printer and with a memory. The memory delivers the message, so the characters to be printed are printed at least in part on the basis of data stored in the memory.

0010With the transmission control system connected between the transmission connection and the memory, the advertising slogan can be selectively changed by the data center if a request is forwarded to the data center via the transmission connection with the message input device, the verification of the coded request in the data center was positive and the message transmitted by the data center has been checked in the franking machine. It has also already been proposed to allow a third party to advertise in their own mail by letting the space for the franking machine message. A third party message is then transmitted to the data center. The data center must feed the third party's message to the franking machine and also controls the use of the message in the franking machine. However, measures are always required to ensure that the connection is maintained, that the message is authorized and that the data is correct.

0011It is not possible to change the message without a check in the data center. Since the memory is directly connected to the printer and stores the print data for the message, the user cannot check which print data is currently stored in the memory. The use of the message stored in this way cannot be controlled arbitrarily by the user of the franking machine.

0012In order to selectively change the advertising message stored in the memory, either the pixel data for the advertising message must be completely re-transmitted from a center, the number of prints being monitored, or the advertising message to be printed is manually entered into a memory via a keyboard in order to be successively to print the postage, date and text lines.

0013The disadvantage here is that when manual input information is changed, the previous old input information is lost. Only advertising messages stored in the headquarters can then be accessed. Another disadvantage is that the change cannot be made without interruption. The overprint is electronically and mechanically complex. The use of printing drums, on the one hand, or dot matrix printers, on the other hand, also leads to undesirable noise pollution.

0014The internal structure of the printing drum, which already has dials for the postage value and the date, would also be so complicated that it had already been proposed to arrange a separate second printer in the plate printing drum. From US 3 869 986 it is known to use a second ink jet printer printing the variable data.

0015From US 4,580,144 an electronic franking machine with two thermal printing devices is known, with the first the fixed printed image part (postal code and picture frame) and the second the variable printed image part (postage and date) being printed in succession. The printing speed can be increased by this division and separate treatment of the variable and constant data. However, due to the lack of a fingerprint, there is no security imprint per se. Rather, an additional marking would also have to be printed on.

0016In the case of a franking machine known from US Pat. No. 4,746,234, fixed and variable information is stored in storage means (ROM, RAM) in order to read it out by means of a microprocessor when a letter actuates a microswitch on the transport path in front of the printing position and to send a print control signal form. Both are then electronically assembled into a print image and can be printed out on an envelope to be franked using thermal printing media. With a large number of variable window print image data to be integrated, the formation of the print control signal is delayed accordingly. The maximum print speed that can be achieved with the same postal data is limited in particular by the time required for the formation of the print control signal. Additional material expenditure would have to be made or the reduction in printing speed would have to be accepted if a crypto number was to be calculated from the data in order to generate a marking for a security print. In both cases, such a machine (high price and / or too slow) would ultimately result in a lack of customer acceptance.

0017An automatic transmission system with user (chip) cards is known from EP 294 397. The user cards are equipped with a microprocessor and a data output unit. The franking machine has a terminal for the user cards with a value processing section, programming means for a card microprocessor and a processing section microprocessor for executing a programmed handling procedure, a graphic being loaded from the card memory through the terminal into the printer memory. However, the graphics can only be changed as a whole, ie by reloading an externally modified postage stamp including postmark using user cards. Security cannot be increased here by new advertising clichés. Such can be easily generated electronically. On the other hand, a changed advertising cliché would indicate manipulation. However, the postal authority has not yet provided for such an evaluation.

0018DE 38 23 719, on the other hand, discloses a security system for use with a character printing authorization device. A computer of the franking machine is assigned a memory for the data to be loaded for the graphic change and the data for the associated date. When the user searches for a change in funds, the computer of the franking machine accesses an external dialing device via a connection device (modem) which selects a character pattern to be printed. It is envisaged that the printed character pattern will be used to check the security of the authorization of the franking machine. Here, however, the entire printed image having that special character pattern is to be evaluated by the postal authority, which is only possible with great effort.

0019For franking machine printing, on the other hand, it has already been proposed to apply certain hidden or crypted characters, bar code, to the mail item as visible or invisible markings with several print heads, in order to be able to identify forgeries.

0020For example, in US 4,775,246 an alphanumeric number is printed in US 4,649,266 a single alphanumeric number in a number in the postmark, whereby subjective comparisons by the postal officer of such numbers or numbers are not excluded. On the other hand, in US 4 934 846 (ALCATEL) a machine-readable bar code is already printed in a separate field next to the postage stamp, but this disadvantageously reduces the available printing area for the postmark and / or the advertising slogan.

0021Such a bar code by means of a separate printer is known from US Pat. No. 4,660,221 and US Pat. No. 4,829,568, the latter US patent also printing a character with offset elements, the offset of which contains the relevant security information. The evaluation is carried out, for example, in US Pat. No. 4,641,346 by reading such a character in columns and comparing it with stored characters in columns in order to recover the security information. The evaluation is accordingly complicated and can only be carried out by the postal authority using complex equipment.

0022Since the representation of the bar or bar code requires a relatively large amount of space, a two-dimensional bar code has already been proposed. However, the disadvantage remains that bar codes can only be checked automatically, ie not additionally manually. A security system known from US 4 949 381 uses imprints in the form of bitmaps in a separate marking field under the franking machine stamp printing. Although the bitmaps are packed particularly densely, the size of the marking field still reduces the height of the stamp image by the height of the marking field. This means that too much of the space required for an advertising cliché is lost. Another disadvantage is the high-resolution detection device required to evaluate the marking.

0023Another security system uses imprints in the form of a diagram (US Pat. No. 5,075,862) within the franking machine stamp imprint. If printing elements have failed, the dots are missing in the printed image, which can signal an alleged forgery. Such markings in diagram form within the franking machine stamp imprint are therefore not so secure. Mechanical evaluation is difficult even with an error-free print, since the entire printed image must always be evaluated.

0024Furthermore, DE 40 03 006 A1 has proposed a method for identifying mail to enable franking machines to be identified, a multi-digit crypto number including the date, the machine parameters, the post value and the advertising slogan being formed and cached separately. The crypto number is additionally inserted into the print pattern during printing via a printer control which sets the printer means. Thus, a counterfeit or any imitation of the franking machine stamp can be identified by means of the crypto number by means of a postage imprint that has not been billed. Even with a large number of users of a single franking machine, the user who manipulated the postage value can easily be found out. However, this is not a fully electronically generated print image for an impact-less printer.

0025Already for security reasons, DE 40 34 292 has proposed for a fully electronically generated print image to store only a constant part of the franking image in the franking machine and to send the other associated variable part from the data center of the franking machine in order to assemble the final printed image.

0026For the compilation of print data, communication of the terminal device containing a franking module with a central office is necessary for each franking. This delays printing, which also makes this solution unsuitable for mass franking of large mail volumes. In this solution, the fully electronically generated advertising cliché is just as much a part of the constant data of the franking image as the frame arrangement of the value and day stamp with location and, if applicable, the postcode. However, the advertising cliché cannot be partially modified in that franking machine.

0027The aforementioned solutions are either too expensive to achieve a high printing speed or have multiple printers or are unsuitable for time-optimized compilation of constant and variable data to form a print control signal for a single printer.

0028On the one hand, all previous solutions in which editing can be carried out do not allow a quick, uninterrupted change of an advertising slogan text part, with a high printing speed of up to approx. 6000 letters per hour. On the other hand, each embassy so far only contains the information previously agreed with the postal authority or, if a single message can be selected, a selection of agreed information. Every deviation leads either to the identification of a forgery or to a reduced security against forgery if such a deviation is permitted.

0029It was therefore the task of overcoming the disadvantages of the prior art in order to create a method for evaluating security imprints which were generated by a franking device on mail items.

0030The object is achieved with the characterizing features of claim 1.

0031This is based on a franking device for which, on the one hand, a machine-readable as well as manually readable and decodable form of identification, which can be visibly applied to the mail piece or the franking strip together with the franking imprint, and for which, on the other hand, a solution for combining constant and of quickly changeable editable data as well as for print control for a column-wise printing of a franking print image was developed. As an additional function, the cliché should be changed via the actuating elements in the new franking machine, without this requiring prior approval from a data center or from the post office, and without this affecting the security of the billing and without such franking Mail is sorted out as a forgery at the post office. At the same time, the security against counterfeiting should also be increased.

0032It should still be easy for the postal authority to distinguish between franking machine imprints manipulated with forgery and those that have not been manipulated but have an editable cliché text part. In addition, there should be a reference to the machine that was mimicked by the manipulator or that was manipulated itself and a reference to the machine that the user continued to operate after the inspection date and / or could be determined from the imprint.

0033Based on the idea of ​​using a microprocessor and a printing module of a franking machine, it is proposed for the security imprint to embed the variable data of the marking in one or more windows within a fixed frame given by the franking machine print image during printing in the case of a fully electronically generated print image. For the time-critical generation of the marking data, at least one combination number of predetermined sizes is formed after the completion of all the inputs and this is encrypted according to an encryption algorithm to a crypto number, which is then converted into a marking. Here, at least one number assigned to the higher digits of the combination number is a monotonically variable quantity. As a result, the marking changes with each print, which makes such a franked item of mail unmistakable.

0034This marking is preferably printed in the form of a bar code and / or as a series of symbols in a field of the franking machine image simultaneously with this by the single printer module. In addition to the mechanical, the symbolism also enables a visual evaluation in the post office by a trained examiner who evaluates the shape and the conceptual content of the symbols. The shape of the symbols, with orthogonal edges, enables particularly easy and quick machine readability via an integral measurement of the degree of blackening. Compared to the bar code, the row of symbols achieves a higher density of information and thus saves space in the franking machine printed image, or more information can be printed coded using the graphic symbols.

0035A major reason why the print speed is not reduced, but rather can be increased overall, due to the time required for the formation of the marking data, is the development of a time reserve during printing by the microprocessor of the control device, which performs the columnar embedding of window data.

0036For the method for the rapid generation of a security imprint for franking machines, which generates coded marking data before a print request after editing window data and / or frame data of the franking machine stamp image from the same microprocessor of a control device which takes over the accounting and sequence control, it is therefore provided that a print control signal is formed after a print request, by inserting the marker data converted into binary pixel data into the currently printed column at a predetermined position during the column-by-column printing in the course of a special printing routine.

0037The invention is based on the fact that, after switching on, the postage value in the value print corresponding to the last entry before switching off the franking machine and the date in the day stamp corresponding to the current date are automatically specified that the variable data in the fixed data for the frame are to be printed and be electronically embedded for all associated data that remain unchanged. These variable data of the window contents are referred to below as window data and all fixed data for the value stamp, the day stamp and the advertising slogan stamp as framework data. The frame data can be taken from a first memory area of ​​a non-volatile working memory. The window data can be taken from a second memory area for the purpose of combining them into an overall representation of a franking image. According to the invention, the data from the two memory areas are combined in accordance with a freely selectable assignment before printing to form a pixel print image and are completed during printing to form a column of the entire franking machine print image. Those variable data which are embedded in the printing column during printing comprise at least the marking data. The time required for the previous assembly of the entire pixel image with the remaining data is reduced accordingly.

0038The previous composition is similar to the date in the postmark and the postage in the value print, whereby the variable information can be added and modified subsequently in the window provided. It is assumed that a variable part of the text can be embedded in a frame for an advertising cliché in the same way as for the other window data and that a window is defined within the overall display of the advertising cliché. In order to save time, only those parts of a graphic display that are actually changed are saved when a change is made.

0039In preparation for a change of cliché text parts for franking machines, the method assumes that loading of agreed cliché types via MODEM or chip card and selection of a cliché type can be carried out in a manner known per se. According to the invention, an optional editing of a cliché text part stored in the franking machine as well as a composition and the display of an overall representation and possibly a saving of the edited text part before printing is additionally guaranteed.

0040According to the invention, the arrangement for changing the cliché text part for franking machines has a pixel memory and a non-volatile working memory with separate memory areas. In addition to the first memory area for the corresponding frame data, the fixed data being assigned to the different cliché types for a selection, the second memory area is provided for window data, inter alia for a number of assignable cliché text parts. The non-volatile memory is connected to a device which can automatically change the data in this second memory area in a predetermined manner.

0041In particular, a message is to be transmitted in an agreed window of a field for an advertising cliché in the franking imprint, the message directly addressing the addressee in plain text. The message can be an alphanumeric text part that has not been agreed with the post office and contains any information, such as information about company holidays, trade fairs, conferences and / or public events.

0042So far, the postal authority has been required to authorize every change requested by the user. The invention is therefore further based on the consideration of agreeing an approval procedure for cliché types that can be supplemented in part by the customer, in order to enable the function in the franking machine to change alphanumeric text parts within the cliché in the franking machine. This eliminates the need to request new advertising clichés from the franking machine manufacturer or dealer or its data center each time, and the associated complex security procedure, including the transmission of coded signals for cliché data using a modem, is also eliminated.

0043On the one hand, a change in the text may not lead to reduced security against counterfeiting, and on the other hand, when checking the franking of postal items that are provided with such a change in the cliché text part, it should not automatically cause the postal items to be rejected as supposedly counterfeited. A corresponding marking is therefore generated for a security imprint, taking into account the fixed franking machine pixel image data, which remain unchanged when the cliché text is edited.

0044Advantageously, for the modification of a cliché text part, already saved, edited text parts are used, so that the advertising cliché can be partially changed or adapted to the current requirements during the ongoing printing of a stack of mail, without causing an interruption in printing.

0045According to the invention, it is proposed to transfer hexadecimal frame data, window data and assignment data into the respective separate memory areas of an additional non-volatile working memory and to store them there in order to display the printed image before printing and to be able to edit the cliché text parts. It is then transferred to the volatile pixel memory and the window data is classified according to the assignment data in the frame data. Here, however, it is possible through the invention to work in a time-optimized manner, so that the printing speed becomes high.

0046Advantageous developments of the invention are characterized in the subclaims or are shown below together with the description of the preferred embodiment of the invention with reference to the figures. Show it:<dl id="dl0001"><dt>Figure 1,</dt><dd>Block diagram of a first variant of the franking machine according to the invention,</dd><dt>Figure 2,</dt><dd>Flow chart for the print image creation according to a second variant of the franking machine according to the invention with three pixel memory areas,</dd><dt>Figure 3a,</dt><dd>Representation of a security imprint with a check box</dd><dt>3b to 3e,</dt><dd>Further variants of the arrangement of marking fields for security imprint</dd><dt>Figure 3f,</dt><dd>Representation of a set of symbols for a marking field in the advertising cliché</dd><dt>Figure 4,</dt><dd>Safety imprint evaluation device,</dd><dt>Figure 5,</dt><dd>Flow chart according to a third variant of the franking machine according to the invention with two pixel memory areas,</dd><dt>Figure 6,</dt><dd>Flow chart according to a fourth variant of the franking machine according to the invention with a pixel memory area,</dd><dt>Figure 7,</dt><dd>Postage stamp image with assigned print columns,</dd><dt>Figure 8,</dt><dd>Representation of the window parameters relating to a pixel memory image and stored separately therefrom,</dd><dt>Figure 9a,</dt><dd>Decoding of the control code, decompression and loading of the fixed frame data as well as formation and storage of the window parameters,</dd><dt>Figure 9b,</dt><dd>Embedding of decompressed current window data of type 1 in the decompressed frame data after the start of the franking machine or after editing frame data,</dd><dt>Figure 9c,</dt><dd>Embedding decompressed variable window data of type 1 in the decompressed frame data after editing this window data of type 1,</dd><dt>Figure 10,</dt><dd>Formation of new coded window data of type 2 for a marking image,</dd><dt>Figure 11,</dt><dd>Decoding of control code and conversion into decompressed binary window data of type 2,</dd><dt>Figure 12,</dt><dd>Print routine for the compilation of data from the pixel memory areas I and II,</dd><dt>Figure 13,</dt><dd>Print routine for the compilation of data taken from a pixel memory area I and working memory areas,</dd></dl>

00471 shows a block diagram of the franking machine according to the invention with a printer module 1 for a fully electronically generated franking image, which contains an advertising slogan and / or a marking for a security imprint, with at least one input means 2 having actuating elements, and with a display unit 3, both of which have a Input / output control module 4 are coupled, a non-volatile memory 5 for at least the constant parts of the franking image and with a control device 6. A character memory 9 supplies the necessary print data for the volatile working memory 7. The control device 6 has a microprocessor μP, which with the input / output control module 4, with the character memory 9, with the volatile working memory 7 and with the non-volatile working memory 5, with a cost center memory 10, with a program memory 11, with a transport memory or feed device, if necessary, is connected to a strip release 12, an encoder (coding disc) 13 and a clock / date module 8.

0048All alphanumeric characters or symbols are stored in pixel memory 9 as binary data. Data for alphanumeric characters or symbols are stored in compressed form in the non-volatile working memory 5 in the form of a hexadecimal number. According to the position report provided by the encoder 13 about the feed of the postal items or Strip of paper in relation to the printer module 1, the compressed data are read from the working memory 5 and converted with the help of the character memory 9 into a printed image having binary pixel data, which is stored in such a decompressed form in the volatile working memory 7. Working memories 7a, 7b and pixel memory 7c are used below to explain the invention, although this is physically preferably a single memory chip.

0049The working memory 7b and the pixel memory 7c are connected to the printer module 1 via a printer controller 14 which has a print register (DR) 15 and an output logic. The pixel memory 7c is connected on the output side to a first input of the printer controller 14, at whose further control inputs there are output signals from the microprocessor control device 6.

0050The arrangement for the rapid generation of a security imprint for franking machines has a first memory area A in the non-volatile working memory 5 (for the data of the constant parts of the franking image, among other things, the advertising slogan frame, an associated index i identifying the respective frame), and a pixel memory area I in volatile pixel memory 7c. For a quick change of the window data, in particular for a quick change of the cliché text part, there is a second memory area B in the non-volatile working memory 5 and a pixel memory area II in the pixel memory 7c for the selected decompressed data of the variable parts of the franking image. A saved block of cliché text is further identified by an assigned name or indication j.

0051The data for a first assignment of the names of the cliché text parts to the names of the cliché frames are available in a third memory area C of the non-volatile working memory 5. With this assignment, the data records in memory areas A and B can be addressed and called up automatically.

0052The memory areas A to T in the non-volatile working memory 5 can contain a large number of sub-memory areas, under which the respective data are stored in data records. The sub memory areas A_i are for i = 1 to m frame or fixed data, B_j for j = 1 to n window data and B_k provided for k = 1 to p window data, different assignments between the sub-storage areas of the different storage areas being selectable and / or stored in a predetermined manner.

0053The strings of numbers (sTrings) that are entered for the generation of the input data with a keyboard 2 or via an electronic scale - not shown in FIG. 1 - connected to the input / output device 4 and calculating the postal value are automatically stored in the memory area T of the non-volatile memory 5 stored. This ensures that the last input values ​​are retained even when the franking machine is switched off, so that after switching on the postage value in the value print corresponding to the last entry before switching off the franking machine and the date in the day stamp according to the current date is automatically specified. In addition, records of the sub memory areas, for example A, also remain_i, B_j, C etc. received. In each data record of a sub memory area A_i, B_j or B_k control code and run length-coded frame or window data are contained alternately one after the other.

0054The corresponding temporary assignment of window to frame data is made by the control device 6 having a microprocessor after switching on according to the current or the specified future date. Before printing, the respective selected frame data for the advertising slogan stamp, for the postmark and for the postage stamp are taken from the non-volatile working memory 5 into the registers 100, 110, 120, ..., of a volatile working memory 7a, the control code being decoded during the takeover and be stored in a separate memory area of ​​the working memory 7b. The respective selected window data are also loaded into registers 200, 210, 220, .... The registers of sub-memory areas are preferably formed in the memory area of ​​the main memory 7a. In another variant, these aforementioned registers are part of the microprocessor control 6.

0055Decompression converts the run length-encoded hexadecimal data into corresponding binary pixel data. The decompressed binary pixel data, which remain unchanged over a longer period of time, are transferred to a first pixel memory area I and the binary pixel data, which change frequently, to a second pixel memory area II. FIG. 1 shows a block diagram for such a first variant of the solution according to the invention.

0056New frame and / or window data can be selected as long as there is still no print request after the insertion and storage of binary pixel data in the first pixel memory area I and the selection of editable window data with subsequent decompression and their storage as binary pixel data in the second pixel memory area II .

0057For example, a large number of the same letters are to be provided with the same date and postage free, with the same cliché text part that is loaded into the second pixel memory area II being able to be exchanged at the same moment as the input was made. It is particularly advantageous if the security markings are also accommodated in such a window in the postage stamp or in the day stamp or between the two stamps. The pixel memory area II is reloaded with the decompressed window data, which correspond to the selected ones stored compressed in the memory areas of the main memory 5, before printing. The combination with the other binary pixel data stored in the pixel memory area I is preferably carried out after a print request has been made during a print routine. The printing need not be interrupted to select the cliché text part data. The invention thus enables a quick, uninterrupted change of the advertising slogan text part and the marking, up to a printing speed of approx. 6000 letters per hour, for example based on the 16 bit processor technology.

0058The number of printed letters with the respective above setting of the advertising cliché is registered in the franking machine for later evaluation.

0059In a further embodiment of this first variant, a large number of separate pixel memory areas for frame and window pixel data are provided in a manner not shown in the figures. The window data concern among others the current postage value (postage) and franking machine-specific data (serial number) in the franking stamp, the date or additional suitable data (absolute time or quantity) in the postmark, editable cliché text part data in the cliché stamp. The composition of the frame and window pixel data takes place again - as in the first variant - during the execution of a special printing routine.

0060FIG. 2 shows a second variant of the solution according to the invention. In addition, specially generated encrypted marking data stored in a sixth memory area F can be used for the marking. The arrangement for changing the cliché text part for franking machines now has three separate memory areas in the pixel memory. In addition to the first memory area I for the data of the plate type (frame), the postal value and the current date and the second memory area II for assignable multiple plate text part data, a third memory area III is provided for the marking data. The device which can change the data in this first, second and third memory area is the same microprocessor of the control device 6 which also executes the accounting routine and the printing routine. The data from the three memory areas are put together in accordance with a previously defined (freely selectable within certain limits) assignment during printing to form an overall representation of an advertising slogan.

0061In particular, in a modification of the solution shown in DE 40 03 006 A1, marking of postal items on the basis of a crypto number generated marking to enable identification of franking machines can be carried out without difficulty if the multi-digit crypto number is not included, including the data values ​​stored as a hexadecimal number entire clichés, but only including selected data values ​​from the cliché framework and other data, how the machine parameter of the value setting and the date is formed and temporarily stored.

0062It is assumed that not only numerical or numerical values, such as the number of the advertising cliché used, but data values ​​of the image information are used to form the encrypted information. In contrast to DE-PS 40 03 006, any area of ​​the advertising cliché, to which separate data in a data record are assigned, can be used to form the crypto number. For this purpose, individual data are selected from this data set. It is advantageous that the end of the column for each column to be printed is identified as a control code that follows the hexadecimal data encoded with run length. The run-length-coded hexadecimal data at the top of the data record can preferably be used.

0063In a further development of the solution according to the invention, the associated data of the regional image information in columns is selected from the data record by means of a physical variable that is present and / or generated in the machine, in particular by the current date, in order to extract at least a number of data (hexadecimal numbers).

0064Furthermore, it is also possible to assign a plurality of data records to each advertising slogan number, each data record having the data relating to a sub-area of ​​the advertising slogan. A physical quantity present and / or generated in the machine is used to select the data record with the associated data of the columnar regional image information in order to extract at least a number of data (hexadecimal numbers).

0065Preferably, those run length-coded hexadecimal data corresponding to a predetermined print column are combined with at least some of the data of the machine parameters (serial number, monotonically variable size, time data, inspection data, such as the number of prints during the last inspection) and the postage value into a number in special - in 10 - Combined and encrypted.

0066When new coded window data is formed before it is stored in the third memory area III, the DES algorithm (Data Encryption Standard) for encryption and, in addition, a conversion into a special graphic character set can be used for a high security standard.

0067However, other encryption methods and methods for converting the crypto number into a marking are also suitable.

0068Depending on the amount of information coded, a bar code may take up a considerable amount of space in the franking machine printed image or may require the franking machine imprint to be enlarged, or not all the information can be reproduced in the bar code imprint.

0069According to the invention, a particularly compact print consisting of special graphic symbols is used.

0070A label, for example formed from symbols to be printed, can be placed in front of, behind, under and / or. be printed over a field within the actual franking stamp imprint. According to the invention, this is a human-readable and machine-readable marking.

0071A letter envelope 17 transported under the printer module 1 is printed with a franking machine stamp image. The marking field is located here in a manner which is advantageous for an evaluation in a line below the fields for the value stamp, for the day stamp, for the advertising slogan and, if appropriate, in the field for the optional print addition of the franking machine stamp image.

0072From a representation of a first example of the security imprint, shown in FIG. 3a, it can be seen that there is good legibility for manual evaluation as well as machine readability with good recognition reliability.

0073The marking field is located in a window FE 6 arranged within the franking machine print image under the day stamp. The value stamp containing the postage value in a first window FE 1 and the machine serial number in a second and third window FE 2 and FE 3 may have a reference field in a Window FE 7 and, if applicable, the number of the advertising cliché in a window FE 9. The reference field is used for pre-synchronization for reading the graphic character string and for obtaining a reference value for the light / dark threshold in the case of a machine evaluation. A pre-synchronization for reading the graphic character string is also achieved by and / or in connection with the frame, in particular the postage stamp or value stamp.

0074The fourth window FE 4 in the day stamp contains the current date or the predated date entered in special cases. Below this is an eighth window FE 8 for a compressed precise time indication, especially for high-performance franking machines with tenths of a second. This ensures that no print is the same as another print, making counterfeiting by copying the print with a copier becomes pointless.

0075A fifth window FE 5 is provided in the advertising cliché for an editable advertising cliché text part.

0076FIG. 3b shows the representation of a security imprint with a marking field in the columns between the value stamp and the day stamp, the upstream vertical part of the frame of the value stamp serving for pre-synchronization and possibly as a reference field. A separate window FE7 is therefore not necessary. In this variant, the marking data can be acquired almost simultaneously with a vertical arrangement of the symbol row in a shorter time.

0077It is also possible to save additional windows for the open, unencrypted imprint compared to the windows shown in FIG. 3a. On the other hand, the printing speed can be increased because fewer windows have to be embedded in the frame data before printing and thus the formation of marking data can begin earlier. To achieve simple copy protection, the crypted print using marking symbols is sufficient, without an open, unencrypted print of the absolute time in a window FE8. In the marking field FE 6, the marking data, which are generated on the basis of at least the post value and such a time count, are already sufficient, as will be explained below with reference to FIG. 10.

0078In a third example of the security imprint - shown in FIG. 3c - in addition to the variant shown in FIG. 3b, a further marking field is arranged in the postmark under the window FE 1 for the postage value. Here, further information, for example about the number of the selected advertising cliché, can be communicated unencrypted but in a machine-readable form.

0079In FIG. 3d, in a fourth example for the security imprint, two further marking fields are arranged in the postmark below and above the window FE 1 for the postage value.

0080In FIG. 3e, in a fifth example for the security imprint, two further marking fields are arranged in the postmark below and above the window FE 1 for the postage value. The marking field, which is arranged in the postmark above the window FE 1 for the postage value, has a barcode. This allows further information, for example about the number of the selected advertising cliché, to be communicated unencrypted but in a machine-readable form.

0081With a smaller number of available symbols set, more symbols have to be printed for the same information. A row of symbols can then be made either in two lines or in the form of a combination of the variants shown in FIGS. 3a to 3e.

0082The form of marking is freely compatible with any postal authority. Any general change of the marking image or the arrangement of the marking field is possible without any problems due to the electronic printing principle.

0083The arrangement for the rapid generation of a security imprint for franking machines allows a fully electronically generated franking image, which was formed by the microprocessor-controlled printing process from fixed data and current data, to be set. For this purpose, a third memory area C is provided in the non-volatile working memory, in which data are available for a first assignment of the names of the variable parts to the names of the constant parts. In contrast, the data for the constant parts of the franking image, which relate to at least the frame of an advertising slogan, are in a first memory area A_i stored, an assigned name identifying the cliché frame, and the data for the variable parts of the franking image are in a second memory area B_j or for marking data in a memory area B_k saved, with an assigned name identifying the variable part.

0084At predetermined intervals, for example regularly with each inspection of the postage meter machine, a change or replacement of the set of symbols - shown in FIG. 3f - can also be carried out in order to further increase the security against forgery.

0085FIG. 3f shows a representation of a set of symbols for a marking field, the symbols being suitably shaped so that both mechanical and visual evaluation by trained personnel in the postal authority is made possible.

0086To increase the security against counterfeiting, a set of symbols is used that is not included in the standard character set of common printing devices.

0087Compared to a barcode, space is saved with a higher information density when the symbols are printed. It is sufficient to distinguish between 10 degrees of blackening, for example to achieve a length of approximately three times shorter in the representation of the information than the ZIP CODE. This results in ten symbols, with the degree of blackening differing by 10% in each case. With a reduction to five symbols, the degree of blackening can differ by 20%, but it is necessary to increase the number of symbols to be printed considerably if the same information as with the symbol set shown in FIG. 3f is to be reproduced. A sentence with a higher number of symbols is also conceivable. Then the row or Corresponding rows of symbols, however, the recognition reliability is also reduced accordingly, so that suitable evaluation devices for digital image processing, for example those with edge recognition, are then required. Due to the continuous use of orthogonal edges and the omission of curves, adequate detection reliability is achieved with simple algorithms of digital image processing. Detection systems of this type use, for example, commercially available line-scan CCD cameras and image processing programs supported by personal computers.

0088Another advantage over a bar code is the good legibility of the individual symbols in the marking field, which is due to the symbolic nature of the image content, and the possibility of linguistically recording the image content for manual evaluation.

0089In the preferred variant, the marking field is arranged at least under or in a field of the franking machine stamp image and a line of such symbols is printed below and simultaneously with the franking stamp impression. The character memory 9 converts a crypto number into a symbol-containing identifier. In particular, a list selected by a further physical variable, advantageously by the postage value, which assigns graphic symbols to the individual crypto numbers, is used. The encrypted hexadecimal data is decompressed by means of the character memory in order to print the identifier formed from the symbols to be printed. This is also a machine-readable marking.

0090The mechanical identification of the symbols in the license plate can be done in two variants: a) via the integrally measured degree of blackening of each symbol or b) via edge detection for symbols.

0091The quantized difference in degree of blackening between the symbols enables simple mechanical evaluation without complex pattern recognition. For this purpose, a suitably focused photo detector is arranged in a reader.

0092This simple machine evaluation is possible even with different colored envelopes. A reference value is derived from the reference field to compensate for different measured values ​​obtained, the difference between which is based on the different printing conditions or paper types. The reference value is used to evaluate the degree of blackening. With this reference value obtained, relative insensitivity to failed printing elements, for example a thermal bar 16 in the printer module 1, can advantageously be achieved.

0093The advantage of a symbol set of the specified type used is that, depending on the requirements of the respective national postal authority, an authentic franking stamp can be identified in a simple manner mechanically (for example by integrally measuring the degree of blackening of the symbols) and / or manually using the conceptual contents of the symbols .

0094The lists, which are created for each serial number or each user and are preferably stored in databases of the data center for all franking machines, contain data values ​​for each variable which are used to check the authenticity of a franking. Thus, on the one hand, the assignment of the symbols to listed values ​​and, on the other hand, in the case of another set of symbols (not shown in FIG. 3f), the assignment of meaning and degree of blackening can be defined differently for different users.

0095A corresponding evaluation device 23 (shown in FIG. 4) for manual identification has a computer 26 with a suitable program in the memory 28, input and output devices 25 and 27. The evaluation device 23 used by the respective postal authority is connected to a data center 21 (not shown in FIG. 4).

0096A suitable procedure for checking security prints consists of the following steps:<ul id="ul0001" list-style="none" compact="compact"><li>a) visual detection of the serial number and its input via an input device 25,</li><li>b) visual detection of the postage value and input via the input device 25,</li><li>c) visual detection of the graphic symbols and input via an input device 25 having correspondingly labeled function keys,</li><li>d) Start of an automatic evaluation, possibly in cooperation with a data center 21 and signaling the comparison result or displaying at least some of the quantities recovered from the marking for manual checking by an inspector of the postal authority.</li></ul>

0097In a first evaluation variant, the graphical symbols are entered into the input device 25 by the trained tester manually or automatically using a suitable reading device 24 in order to convert the marking printed on the mail item (letter) back into at least one first crypto number KRZ1. Here, the actuating elements, in particular the keyboard, of the input device can be identified with the symbols in order to facilitate manual input.

0098In a second step, the openly printed sizes from the franking machine stamp image, in particular G0 for the serial number SN of the franking machine, G1 for the advertising slogan (frame) number WRN, G2 for the date DAT and G3 for the postage value PW, G4 are not per se repeating time data ZEIT and from at least one size G5 INS known only to the franking machine manufacturer and / or the data center and communicated to the postal authority, to form at least one comparison crypto number VKRZ1.

0099The check is carried out in a third step by comparing the crypto numbers KRZ1 with VKRZ1 in the computer 26 of the evaluation device 23, a signal for authorization in the case of equality or the non-authorization in the event of a negative comparison result (inequality) being emitted.

0100A second evaluation variant consists in recovering the individual information from the printed marking and comparing it with the information openly printed on the mail piece. If the crypto numbers for the marking were generated according to a symmetrical algorithm (for example DES algorithm), then after the first step of the first evaluation variant, the initial number can be generated again from each crypto number. The starting number is a combination number KOZ and contains the number combination of at least two sizes, one size being represented by the upper digits of the combination number KOZ and the other size by the lower digits of the KOZ. The part of the number combination that is to be evaluated - for example, the postage - is separated and displayed. Thus, the second and third steps of the first evaluation variant are omitted.

0101A device equipped with an appropriate program (laptop) is sufficient for evaluation. In this case, sizes G1, possibly G4, which may not be removed from the franking machine stamp image, and at least one size G5 known only to the franking machine manufacturer and / or the data center and communicated to the postal authority can be encoded. These are also recovered from the marking by decryption and can then be compared with the user-specific saved values. The lists stored in the memory 28 can be updated via a connection to the data center 21. Further details are given in connection with step 45, shown in FIG. 10, of forming new coded window data of "type 2" for a marking image.

0102In a third evaluation variant, variables G0, G2, G3 and G4 are manually or automatically entered into the evaluation device by the operator in order to derive a crypto number using the same key and encryption algorithm used in the franking machine. A marking generated from this is displayed and compared by the operator with the marking printed on the postal matter (envelope). This is accommodated by the symbolism of the markings shown in the output unit 27 and printed on the postal matter.

0103If an uncomplicated (possibly simple asymmetrical) encryption algorithm is used, a purely mechanically acting template can be produced, for example - which is not shown in the figures - and which is set accordingly and displays individual symbols. In addition to the frame number of the advertising cliché frame that is recognizable for the viewer, the serial number, the date from the postmark and the postage value from the franking stamp must be set. A row of symbols formed from this is displayed and can be compared with the row of symbols shown in the marking field. The check is carried out by comparing the markings in order to determine whether there is equality or the ineligibility in the event of a negative comparison result (inequality).

0104The first size G1 is the advertising slogan frame number WRN, which the inspector recognizes from the franking stamp image. In addition to the user, this first size is also known to the franking machine manufacturer and / or data center and is communicated to the postal authority. In a variant, preferably with a data connection to the data center, the advertising slogan frames WR belonging to the serial number SN of the respective franking machine are used_n with assigned numbers WRN_n is displayed on a screen of the data output device 27. The comparison with the advertising slogan frame WR used on the letter_b is carried out by the examiner who has the number WRN determined in this way_n enters.

0105The stored lists transferred from the data center into the memory 28 contain on the one hand the current assignment of the parts of the advertising slogan frame WRNT to a second size G2 (for example the date DAT) and on the other hand the assignment of symbol lists to a third size G3 (for example the post value PW) ). In addition, a list of parts SNT of the serial number SN selected by the first size G1, in particular the advertising cliché (frame) number WRN, can be present. User-specific information, such as, for example, the advertising slogan frame number WRN, can be used for random manual evaluation of the marking, in that decoding lists can be selected on the basis of the user-specific information and contain the corresponding data records. The size G2 (DAT) is then used to determine the byte from the data record which is used when generating the combination number.

0106In the preferred variant, a monotony check is used on the one hand to check the unmistakability of the impression. The examiner takes the serial number SN from the windows FE2 and FE3 of the impression and determines the franking machine user. In this case, the advertising slogan number can also be used, since these are usually assigned to certain cost centers if the same machine is used by different users. In the above Lists are data from the last inspection, including data from the last inspection. Such data are, for example, the number of pieces if the machine has an absolute piece count, or the absolute time data if the machine has an absolute time count.

0107In the first test step, the correctness of the printed postal value is checked in accordance with the valid regulations of the postal authority. Subsequent manipulations on the value print can be detected with fraudulent intent. The monotony of the data, in particular that in window FE8, is then checked in the second test step. This allows copies of a franking imprint to be identified. Manipulation for the purpose of forgery is therefore not promising, since this data is additionally printed in the form of a crypted row of symbols in at least one marking field.

0108In the case of an absolute time or piece count, the number given in window FE8 must have increased since the last check. In the window FE8 nine digits are shown, which allows the display of a period of approx. 30 years with a resolution of seconds. Only after this time would the counter overflow. These sizes can be recovered from the marking in order to compare them with the openly printed, unencrypted sizes.

0109In a third optional test step, if manipulation is suspected, the other variables, in particular the serial number SN of the franking machine, and possibly the user's cost center can also be checked and ascertained.

0110The information, such as the advertising slogan (frame) number WRN, on the other hand, can be indicated by a predetermined window FE9. The associated window data are of type 1, ie they are changed less often than window data of type 2, such as the time data in window FE8 and the marking data in window FE6.

0111In a further embodiment variant, the data of the windows FE8 and FE9 are not printed openly unencrypted, but are only used for encryption. For this reason, the windows FE8 and FE9 shown in FIG. 3a are missing in the franking machine print images - shown in FIGS. 3b to 3e - in order to clarify these variants.

0112In a preferred input variant for the test, the temporarily variable quantities to be entered, for example the advertising slogan (frame) number WRN, the date DAT, the postage value PW, time data TIME and the serial number SN are automatically detected by means of a reader 24 from the corresponding field of the franking machine stamp image and read. The arrangement of the windows in the franking machine imprint must be observed in a predetermined manner.

0113Other temporarily variable sizes assigned to the respective serial number SN are only known to the franking machine manufacturer and / or data center and are communicated to the postal authority. For example, the defined number of frankings achieved during the last inspection serves as a fifth size G5.

0114All sizes to be entered, except sizes G1, G4 and G5, must be in the individual windows FE_j the franking machine stamp image can be removed. The size G5 forms, for example, the key for the encryption, which is changed at predetermined time intervals, ie after each inspection of the franking machine. These time intervals are dimensioned such that even when using modern analysis methods, for example differential cryptanalysis, it is certainly not possible to reconstruct the original information from the markings in the marking field in order to subsequently produce counterfeit stamp images.

0115For example, size G1 corresponds to an advertising cliché (frame) number. In the sub-storage areas T_i , T_j of the working memory 5 of the franking machine are corresponding number strings (sTrings) for window or Frame input data saved.

0116The sizes G0, G2 and G3 correspond, for example, to those in the sub-storage areas T._j of the working memory 5 of the franking machine stored window data, the size G0 in the windows FE2 and FE3 from the sub memory areas T₂ and T₃, the size G2 in the window FE4 from the sub memory area T₄ and the size G3 in the window FE1 from the sub memory area T₁ comes from.

0117The following steps are provided for changing the cliché text part for franking machines:<ul id="ul0002" list-style="none"><li>a) Loading agreed cliché frames via MODEM or chip card,</li><li>b) selecting a cliché frame,</li><li>c) editing of a cliché text part that is automatically saved before franking,</li><li>d) assembling and displaying an overall representation of the franking image,</li></ul>

0118If steps a) to c) have already been carried out beforehand, the saved cliché frames with the cliché text parts used can be displayed and selected immediately in order to change the cliché or to combine a cliché with the selected cliché text part without interrupting printing.

0119It is furthermore provided that in the display unit 3 of the franking machine for the selection of a cliché frame, a number of names of the cliché frames or a clear representation for the selection of the cliché frames with an associated cliché or standard text part takes place from a pixel memory. By acknowledging the selection, at least one of the variable text parts for FE5 is assigned to the respective cliché frame. The selected cliché text part can be edited with the plain text on the display using the actuating elements. After editing a cliché text part for the window FE5 and assembling and displaying an overall representation of a franking image, the edited text part is automatically saved before franking, with a new data record or a new assignment of the edited text part to the cliché frame in the memory areas B₅ or C is saved.

0120The windows within the overall display of the advertising cliché are defined in such a way that in a separate sub-storage area B₅ save only the parts of a graphical representation in the event of a change that are actually changed. The data of the window contents can be extracted from the storage area B for the purpose of composing them into an overall representation of a franking image. A run-length coding of graphic data was provided in at least one area of ​​the non-volatile working memory 5, the first code of each line of the coding indicating the number of pixels to be printed per column and control codes, for example for the start of the respective window (types 1 or 2), Column end, picture end in hexadecimal representation are available.

0121The cliché frame data and the data for the variable cliché text parts are stored in the memory areas A_i and B₅ removed if necessary, taking the assignment into account. In the sub-storage areas B₅ several data records for the cliché text parts are preferably stored. At the start, the user enters his cost center, whereby a predetermined cliché frame data record from the storage area A_i is selected. Since the selectable cliché frames are each assigned to a cost center KST and / or a second assignment of the cliché type number to cost centers is stored in a fourth memory area D, the control device 6 can carry out the predetermined compilation of the print image data.

0122It is provided that the names of the cliché frames stored in a first storage area A are composed of the number KN of the cost center K and a type number TN, that the names of the cliché text parts that are stored in a second sub-storage area B₅ are stored, are determined by the current date at the time of generation and possibly by the time UZ and that the data for the first assignment in the third memory area C by storing both the name of the cliché frame containing the cost center number KN and the type number TN, as well as the name of the cliché text part containing a date DAT and possibly a time UZ are determined. Depending on the selected cost center, an assignment is found in the storage area D and a predetermined data record for the cliché frame from A_i selected. The associated cliché text part can be based on the assignment in memory area C in memory area B₅ addressed and then automatically transferred to the designated memory area 7a of the volatile working memory 7.

0123It is further provided that the display required for a cliché selection in the display unit 3 is only made from the names of those cliché frames for which there are assignments in the third memory area C that fall within a defined period. A cliché frame without an existing assignment of a name to a cliché text part name cannot be displayed. The assignment can refer to the period of the current year, for example. After the name has been selected and an acknowledgment has been made, the corresponding cliché frame is displayed in clear form.

0124The names of cliché text parts are displayed in the window provided for that field of the display unit 3, in which the clear representation of the cliché frame is also visible.

0125For another variant of the representation, for a better selection of cliché text parts, the clear representations of the cliché text parts should appear in succession in an order determined by the time data of the name in the window of the field of the display unit.

0126In a preferred variant, the defined period of time is automatically given by the selectable time data in the data of the assignment of cliché text parts, in particular such time data as for example the month and / or the year, in relation to the current date supplied by a clock / date module 8.

0127In a further advantageous embodiment of the concept of the invention, there is an assignment in a fifth memory area E which relates to a freely programmable defined period in which the time data in the data of the assignments of cliché text parts to cliché frames are related to the current date.

0128In the sub-storage areas B₅ B₆ and B₇ In the working memory 5 of the franking machine, the stored window data are available for an advertising slogan text part, a marking field and, if appropriate, for a reference field. It should be noted that in some of the groups named as B_k marked sub-memory areas of the working memory 5 of the franking machine, the window data are written in and / or read out more often than in other sub-memory areas. If the non-volatile working memory is an EEPROM, a special storage method can be used to ensure that it remains safely below the limit number of storage cycles that is permitted for it. On the other hand, a battery-backed RAM can also be used for the non-volatile working memory 5.

0129The window data which can be changed less in time is referred to below as window data of type 1. In contrast, type 2 window data are used to refer to the constantly changing window data.

0130In comparison to the second variant shown in FIG. 2, FIG. 5 now shows a third variant of the solution according to the invention, the method being based on the presence of two pixel memory areas shown in FIG. 1.

0131According to the frequency of a change in data, decoded binary frame and window data are stored in two pixel storage areas before printing. The type 1 window data, such as the date, serial number of the franking machine and the cliché text part which is not to be changed continuously, can be decompressed together with the frame data in binary data before printing and combined to form a pixel image stored in the pixel memory area I. In contrast, constantly changing type 2 window data is decompressed and stored as binary window data in the second pixel memory area II before printing. Type 2 window data are the postage and transport-dependent postage value to be printed and / or the constantly changing marking. After a print request, the binary pixel data from the pixel memory areas I and II are combined to form a print column control signal for each column of the print image during the course of a print routine.

0132After the start in step 40, based on the input of the cost center in step 41, the window and frame data that was last saved are automatically entered and in step 42 a corresponding display. In the manner described above, a cliché text part that is assigned to a specific advertising cliché can be automatically specified.

0133In step 43, frame data in register 100, 110, 120,... Of the volatile working memory 7a are adopted and control code is detected and stored in the volatile working memory 7b. The remaining frame data are decompressed and stored in the volatile pixel memory 7c as binary pixel data. Likewise, the window data are loaded into registers 200, 210, 220, ..., of the volatile working memory 7a, and control code is detected and stored in the volatile working memory 7b, and the other window data are accordingly stored in columns in the volatile pixel memory 7c after they have been decompressed.

0134In Figure 9a, the decoding of the control code, decompression and loading of the fixed frame data as well as the formation and storage of the window parameters and in Figure 9b the embedding of decompressed current window data of type 1 in the decompressed frame data after the start of the franking machine or shown in detail after editing frame data.

0135In step 44, either the decompressed frame and window data of type I are stored as binary pixel data in the Pichel storage area I and can be processed further in step 45, or frame and / or window data is re-entered. In the latter case, step 51 is branched to.

0136In step 51, the microprocessor determines whether an input has been made via the input means 2 in order to replace window data, for example for the postage value, with a new one, or to replace or edit window data, for example for a cliché text line. If such an entry has been made, the necessary sub-steps for the entries are carried out in step 52, ie a finished other data record is selected (cliché text parts) and / or a new data record is generated which contains the data for the individual characters (numbers and / or letters) of the input size.

0137In step 53, corresponding data sets are called up for a display for checking the input data and are provided for the subsequent step 54 for reloading the pixel memory area I with the window data of type 1.

0138FIG. 9c shows the step 54 for embedding decompressed variable window data of type 1 in the decompressed frame data after a new entry or after editing this window data of type 1. The data from data records called up according to the input are evaluated in order to detect control codes for a "color change" or a "column end" which are necessary for embedding the newly entered window data. Then those data that are not control codes are decompressed into binary window pixel data and embedded in the pixel memory area I in columns.

0139If, on the other hand, it was determined in step 51 that no window data should be selected or edited, a branch is made to step 55. In step 55, the possibility of changing the fixed advertising slogan or frame data leads to a step 56 in order to carry out the input of the currently selected frame data records together with the window data records. Otherwise, the process branches to step 44.

0140If a new input of selected special sizes is to take place, a flag is set in step 44 and taken into account in the subsequent step 45 for the formation of data for a new series of marking symbols if a step 45b is to be processed here according to a second variant.

0141The new coded window data of type 2 is formed in step 45. The marking data for a window FE6 are preferably generated here, preceding steps for encrypting data to generate a crypto number being included. In this step 45, a shape as a bar code and / or symbol chain is also provided. The formation of new, coded type 2 window data for a marking image is explained in two variants on the basis of FIG. In a first variant, a monotonically variable size is processed in a step 45a, so that ultimately each print is unmistakable due to the printed symbol row. In a second variant, other sizes are processed in a step 45b before step 45a.

0142The correspondingly formed data record for the marking data is then stored in an area F and / or at least in a sub-storage area B.₆ of the non-volatile working memory 5 is loaded and overwrites the previously stored data record, for which window characteristic values ​​have already been determined or are predetermined and are now only stored in the volatile working memory 7b. The sub memory area B₁₀ is preferably provided for a data record which leads to the printing of a second row of marking symbols, as is shown in FIGS. 3c and 3d. In addition, double rows of symbols can also be printed side by side - in a manner not shown in FIG. 3b. The area F is preferably provided for a data record which leads to the printing of a bar code, as is shown in FIG. 3e.

0143In step 46, the data of the data record is transferred byte by byte for the marking in registers in the volatile main memory 7a and the control characters "color change" and "column end" are detected, in order then to decode the remaining data of the data record and to decode the binary window pixel data of the type 2 to load into the pixel memory area II of the volatile working memory 7c. FIG. 11 shows in detail the decoding of control code and conversion into decompressed binary window data of type 2. Such type 2 window data are identified in particular by the index k and relate to the data for the window FE6, possibly FE10 for marking data and possibly FE8 for the TIME data of the absolute time count. The time data in particular represent a monotonously changeable, since increasing time-dependent, variable. First of all, BCD-packed time data delivered from the clock / date module 8 are, if appropriate, converted into a data record containing suitable TIME data with run-length-coded hexadecimal data. Now you can also in a memory area B₈ for type 2 window data FE8 and / or immediately loaded in columns 46 in register 200 of the working memory 7a or in the print register 15.

0144In step 47, if a print request has been made, the step 48 containing a print routine is waited for and if the print request has not yet taken place, the print request is waited in a waiting loop. In one embodiment, the waiting loop - as shown in FIGS. 5 and 6 - is directly traced back to the beginning of step 47. In another embodiment, the waiting loop - in one in FIGS. 6 not shown - traced back to the beginning of step 44 or 45.

0145The print routine - shown in detail in FIG. 12 - carried out in step 48 for the compilation of print column data from the pixel memory areas I and II takes place while the print register (DR) 15 is being loaded. The printer controller (DS) 14 effects immediately after loading the Print register (DR) 15 a print of the loaded print column. It is then checked in step 50 whether all columns for a franking machine print image have been printed by the current address Z with the stored end address Z_{The End} is compared. If the printing routine has been carried out for a mail item, a branch is made to step 57. Otherwise, the process branches back to step 48 in order to generate and print the next print column until the print routine has ended.

0146If the printing routine has ended, a check is carried out in step 57 as to whether further mail pieces are to be franked. If this is the case, then franking is ended in step 60. Otherwise the end of printing has not yet been reached and the process branches back to step 51.

0147FIG. 6 shows a fourth variant of the solution according to the invention, in which, in deviation from the block diagram according to FIG. 1, only one pixel memory area I is used. Decoded binary frame data and window data of type 1 are assembled and stored in this pixel memory area I before printing. The steps are identical except for step 46, which is saved here in this variant according to FIG. 6, and step 48, which is replaced here by step 49. Up to step 46 there is essentially the same sequence in the sequence.

0148In FIG. 13, the printing routine for compiling data taken from a pixel memory area I and working memory areas is discussed in more detail.

0149The constantly changing type 2 window data is decompressed in step 49 during the printing of each column and, together with the binary pixel data to be printed column by column, is combined from the pixel memory area I to form a printing column control signal. Type 2 window data are, for example, the postage and transport-dependent postage value to be printed and / or the constantly changing marking.

0150Using a postage stamp image shown in FIG. 7 and the data of the print control signal assigned to a print column, its generation from the frame and window data is explained. A letter envelope 17 is moved under the print module 1 of an electronic franking machine at the speed v in the direction of the arrow and thereby in the column s₁ starting with a grid, printed in columns with the depicted postage stamp image. The printer module 1 has, for example, a print bar 16 with a number of print elements d1 to d240. Ink-jet or a thermal transfer printing principle, for example the ETR printing principle (Electroresistive Thermal Transfer Ribbon), can be used for printing.

0151A column to be printed s_f has a printing pattern 30 to be printed consisting of colored printing dots and non-colored printing dots. A colored printing dot is printed by a printing element. In contrast, the non-colored print dots are not printed. The first two pressure points in the pressure column s_f are colored in order to print the frame 18 of the postage stamp image 30. This is followed by 15 non-colored (ie not active) and 3 colored (ie active) printing dots alternately until a first window FE1 is reached, in which the postage value (postage) is to be inserted. This is followed by a range from 104 non-colored pressure dots to the end of the column. Such run length coding is implemented in the data set using hexadecimal numbers. The space requirement is minimized by having all the data in such a compressed form.

0152With hexadecimal data "QQ" 256 bits can be generated. If the required control code bits are subtracted from this, less than 256 bits remain for driving the dots generating means.

0153If, however, additional control characters "00" causing a color change are used, even more than 256 dots can be controlled, with A_i of RAM 5 but more space is needed. The exemplary embodiments according to FIGS. 9, 11, 12 and 13 are designed for such a high-resolution printer module.

0154Control characters "00" are provided for color changes. This means that a subsequent hexadecimal number is still considered colored (f: = 1), which would otherwise be considered non-colored. A reset color flip-flop (f: = 0) is set when the color changes (f: = 1) and switched again the next time the color changes (f: = 0). With this principle, 256 dots or more can be addressed. The register 15 in the print controller 14 is loaded bit by bit from the pixel memory (e.g. for a printing column with N = 240 dots).

0155Other control characters are "FE" for the end of the column, "FF" for the end of the image, "F1" for the start of the window of the first window FE1, etc.

0156In the following example chosen to explain FIG. 7, less memory space is required in the ROM compared to a print column to be controlled with more than 240 dots, since the control characters are placed favorably. For hexadecimal data "01", "02", ..., "QQ", ... "F0" are 1 to 240 dots ("F0" = [F * 16¹] + [0*16⁰] = [15 * 16] + [0 * 1] = 240) can be controlled.

0157The control code "00" for color changes can theoretically be omitted here, since with a single hexadecimal number "F0" an entire print column of 240 dots with the same coloration can be completely defined. Nevertheless, if there is only an imperceptible additional memory requirement, a change of color can also make sense for several windows in one column.

0158This method results in a data record for the print column s_f in the form shown in sections:<maths id="math0001"><math display="block"><mrow><mtext>... "2", "0D", "02", "4F", "F1", "68", "FE", ..., ...</mtext></mrow></math><img file="EP0907149A2_D0001.tif" /></maths>

0159When transferred to a register 100 of the µP controller 6, control characters are detected from hexadecimal numbers "QQ" and evaluated in the course of a step 43.

0160In this evaluation, window parameters Z_j, T_j, Y_j or Z_k, T_k, Y_k generated and together with specified values ​​for the starting address Z₀, End address Z_{The End} and the total run length R, ie the number of binary data required per printing column, stored in volatile memory RAM 7b.

0161A maximum of 13 windows could be called for the 13 control characters "F1" to "FD" and the start addresses determined. For example, with "F6" for the start of a window FE6 of type 2, a start address Z₆ determine and save as window parameter.

0162FIG. 8 shows the window characteristic values ​​related to a pixel memory image and stored separately therefrom for a first window FE1. The window has a window column run length Y₁ = 40 pixels and a column number of approx. 120, which is the window column variable T₁ is saved. If the window start address Z₁ is stored as the destination address, the position of the window FE1 in the binary pixel image can be reconstructed at any time.

0163Binary data converted from the registers 100, 200 are read bit by bit into the volatile pixel memory RAM 7c, an address being assigned to each bit. If the hexadecimal number loaded in the register is a detected control character "F2", the window characteristic value Z_j determined for a start address of the window of number j = 2 for a total of n windows. This means that window data can later be inserted into the frame data at this point identified by the address. It is the window column run length Y_j &lt;R Total run length of the printing column. From the addition with R the new address can be created in the same row but in the next column.

0164FIG. 9a shows the decoding of the control code, decompression and loading of the fixed frame data as well as the formation and storage of the window characteristic values. A control code "color change" was taken into account when considering the creation of very high-resolution prints. A color flip-flop 1 must therefore be reset to f: = 0 in a first sub-step 4310. The source address H_i to find the framework data, let's start with H_i : = H_i - 1 and the destination address Z: = Z₀ .

0165For the window data of type 1, the window column variable T_j : = 0, for j = 1 to n windows and for window data of type 2, the window column variable T_k : = 0 for k = 1 to p window set. In sub-step 4312 the source address H_i incremented for frame data and a color change carried out so that the initial data byte is evaluated as colored, for example, which later leads to correspondingly activated printing elements.

0166The above-mentioned byte, which is a run-length-coded hexadecimal number for frame data, is now in sub-step 4313 from the area A that is automatically selected by the cost center KST_i of the non-volatile memory 5 is transferred to a register 100 of the volatile memory 7a. Control characters are detected and a run length variable X is reset to zero.

0167In sub-step 4314, a control character "00" for a color change is recognized, which, after branching back to sub-step 4312, leads to a color change, ie the next hexadecimal number coded for the run length inactivates the printing elements in accordance with the run length. Otherwise, it is determined in sub-step 4315 whether there is a control character "FF" for the end of the image. If one is recognized, point d has been reached in accordance with FIGS. 5 or 6 and step 43 has been processed.

0168Otherwise, if such a control character "FF" for end of image is not recognized in sub-step 4315, a check is made in sub-step 4316 as to whether there is a control character "FE" for an end of column. If one is recognized, the color flip-flop 1 is reset in sub-step 4319 and a branch is made to sub-step 4312 in order to then load the byte for the next printing column in sub-step 4313. If there is no end of column, it is determined in sub-step 4317 whether there is a control character for a window of type 2. If one has been recognized, a branch is made to sub-step 4322. Otherwise, it is examined in sub-step 4318 whether there is a control character for type 1 windows. If this is the case, then a point is c₁ reached, at which a step 43b - shown in FIG. 9b - is carried out.

0169If no control character for window data of type 1 is recognized in sub-step 4318, then the run-length-coded frame data are present in the called byte, which are decoded in sub-step 4320 and converted into binary frame pixel data and stored in the pixel memory area I of the pixel memory 7c under the set address Z. In the following sub-step 4321, the column run length variable X is determined in accordance with the number of bits converted and then the target address for the pixel memory area I is increased by this variable X. A point b has thus been reached and a branch is made back to sub-step 4312 to call a new byte.

0170In sub-step 4322, if there was a control character for window data of type 2, the storage of window characteristic values ​​T_k determined. Is a window parameter, in this case the window column run variable T_k still at the initial value zero, the window start address Z_k correspond to the address Z determined and stored in the volatile working memory 7b. Otherwise, a branch is made to a sub-step 4324. Sub-step 4323 also follows sub-step 4324, in which the window characteristic of the window column variable T_k is incremented. In the subsequent sub-step 4325, the previous window column variable T stored in the volatile main memory 7b_k overwritten with the current value, and the point b is reached.

0171The window parameters are thus loaded for k = 1 to p windows, in particular FE6 and possibly FE10 or FE8. The method then branches back to sub-step 4312 in order to load a new byte in sub-step 4313. The bits (dot = 1) converted from the hexadecimal data are therefore transferred in the byte by byte step 43a - shown in FIG. 9a - into the pixel memory area I of the volatile pixel memory 7c and stored in succession as binary data.

0172FIG. 9b shows the embedding of decompressed current window data of type 1 in the decompressed frame data after the start of the franking machine or after editing frame data. Provided that a control character for type 1 windows was recognized in sub-step 4318, point c₁ and thus the beginning of step 43b is reached.

0173In step 4330, the storage of window characteristic values ​​T is carried out_j determined. Is a window parameter, in this case the window column run variable T_j still at the initial value zero, the window start address Z_j correspond to the address Z determined and stored in the volatile working memory 7b. Otherwise, a branch is made to a sub-step 4332. Sub-step 4331 is also followed by sub-step 4332, in which the window characteristic of the window column run length Y_j and the window column run length variable W_j to an initial value of zero and the window source address U_j to the initial value U_oj - 1 and the second color flip-flop for windows should be set to "do not print in color".

0174In the subsequent sub-step 4333, the previous window source address U_j incremented and a color change carried out, so that any window bytes that are loaded in the subsequent sub-step 4334 are evaluated as colored, which subsequently leads to activated printing elements during printing.

0175In sub-step 4334 a byte from the sub-storage areas B_j loaded in the non-volatile working memory 5 in register 200 of the volatile working memory 7a and thereby detected for control characters.

0176In step 4335, the window column run length Y_j by the value of the window column run length variable W_j incremented. In sub-step 4336 it is determined whether there is a control character "00" for color changes. If one has been recognized, the process branches back to sub-step 4333. Otherwise it is examined in sub-step 4337 whether there is a control character "FE" for the end of the column. If this is not the case, window data is available. In a sub-step 4338, the content of the register 200 is decoded with the help of the character memory 9 and the binary window pixel data corresponding to this byte is stored in the pixel memory area I of the pixel memory 7c.

0177Then in a sub-step 4339 the window column run length variable W_j determined to the address Z by the value of the variable W_j to increment. The new address is thus available for a new byte of the data record to be converted, and the process branches back to sub-step 4333, in which the new source address for a byte of the data record is also generated for window FEj.

0178If a control character "FE" for the end of a column was recognized in sub-step 4337, a branch is made to sub-step 4340, in which the window column variable T_j incremented and the volatile working memory 7b stored window column variable T_j and the window column run length Y_j overwritten with the current value. A color change is then carried out in sub-step 4341 and point b has been reached.

0179This completes step 43b and new frame data could be implemented in step 43a if a next window is not recognized or point d has been reached.

0180FIG. 9c shows the embedding of decompressed variable window data of type 1 in the decompressed frame data after editing this window data of type 1. As has already been shown, pixel memory data and window characteristics have already been stored before the start of step 54. The sub-step 5440 begins with the determination of the number n 'of windows for which the data has been changed and a determination of the associated window start address Z_j and window column variable T_j for each window FEj. In addition, a window counter variable q is set to zero E.

0181In sub-step 5441, it is determined whether the value of the window count variable q has already reached the value of the number of window changes n '. If there are zero changes, ie n '= 0, the comparison is positive and point d is reached. Otherwise, a branch is made to sub-step 5442, the window start address Z for a first window FEj whose data has been changed_j and the window column variable T_j can be removed from the volatile working memory 6b. In addition, the source address U_j to an initial value U_oj - 1 set, the destination address Z_j used to address the pixel memory area I, a window column counter P_j and the second color flip-flop is reset to the initial value zero.

0182In the following sub-step 5443, the source address is incremented and a color change is carried out before the sub-step 5444 is reached. In sub-step 5444, a byte of the changed data record is called up in the non-volatile memory and transferred to the register 200 of the volatile memory 7a, control characters being detected. If a control character "00" for color change is branched back to sub-step 5443 in sub-step 5445. Otherwise, branch to sub-step 5446 to look for control characters "FE" for the end of a column. However, if such a control character is not present, the content of the register 200 can be decoded in the subsequent sub-step 5447 with the cooperation of the character memory 9 and converted into binary pixel data for the window to be changed. These now replace the previous pixel data stored in area I of the pixel memory 7c from the window start address Z_j predetermined location. The bits converted in this way are called window run length variables W_j counted with which in step 5448 the destination address V_j is incremented. The method then branches back to sub-step 5443 in order to load the next byte in sub-step 5444.

0183However, if a control character "FE" for the end of the column is recognized in sub-step 5446, then a branch is made to sub-step 5449, in which the window column counter P_j is incremented.

0184In sub-step 5450, it is examined whether the window column counter P_j the window characteristic value for the associated window column variable T_j is reached. Then, for a first changed window, all change data would be loaded into the pixel memory area I and the process branches back to the sub-step 5453 and from there to the sub-step 5441 in order to transfer change data into the pixel memory area I for a possibly second window. For this purpose, the window counter variable q is incremented in sub-step 5453 and the subsequent window start address Z_{j + 1} and as well as the following window column variable T_{j + 1} determined.

0185Otherwise, if in step 5450 the window column variable T_j through the window column counter P_j has not yet been reached, branches back to sub-step 5443 via sub-steps 5451 and 5452 in order to overwrite a further window column in the pixel memory area until the old binary window pixel memory data has been completely replaced by the new one. For this purpose, the target address for the data in the pixel memory area I is incremented by the frame total column length R in sub-step 5451. The target address Vj is thus set to the next column for binary pixel data of the window in the pixel memory area I. In sub-step 5452, the color flip-flop is reset to zero, so that the conversion begins with pixel data that is rated as color. If no further new entry is determined in step 44, new coded window data of type 2 can now be formed in step 45 for a marking image, in particular according to a first variant with step 45a.

0186Step 45 comprises further sub-steps - shown in FIG. 10 - for forming new coded window data of type 2 for a marking image. While there are already decompressed binary pixel data in the pixel memory area I, after step 44 in step 45 the output data for the data records containing the compressed data for the windows FE become again_j and possibly required for the frame data in order to form new coded window data of type 2 for a row of marking symbols. The individual output data (or input data) are in accordance with the respective quantities G._w in the memory areas T_w saved as a BCD-packed number. In addition to the A_i and B_j data records stored in a non-volatile manner, the data for a data record for window FEk of type 2 are now compiled in several steps and in a sub-memory area B_k stored non-volatile.

0187The method for the rapid generation of a security imprint comprises, after provision of quantities, a sub-step 45a carried out by the microprocessor of the control device 6 of the franking machine before a print request (step 47), comprising the sub-steps:<ul id="ul0003" list-style="none" compact="compact"><li>a) generation of a combination number KOZ1, whereby a constantly monotonically variable variable G4 for forming first contiguous digits and at least one further variable G3 characterizing the mail item are provided for forming second contiguous digits of the combination number KOZ1,</li><li>b) encryption of the combination number KOZ1 to a crypto number KRZ1,</li><li>c) converting the crypto number KRZ1 into at least one marking symbol row MSR1 using a set SSY1 of symbols.</li></ul>

0188In a first variant 1, a row of marking symbols is generated in a step 45a. Due to the amount of information by the sizes G0 to G5, which are only to be partially printed openly and unencrypted in the franking machine stamp image, the franking machine preferably uses at least some of the sizes in order to form a single number combination (sub-step 451), which includes a single crypto number is encrypted (sub-step 452) and then converted into a marking to be printed on the postal matter (sub-step 453). The data record to be generated for the marking in a window FE6 can be stored in a final sub-step 454. Then point c₃ reached. This first variant, executed in partial step 45a, saves the time that would otherwise be required in the franking machine for generating further crypto numbers.

0189It is envisaged that the constantly monotonically variable variable G_w is at least one ascending or descending machine parameter, in particular a time count or its complement during the life of the franking machine.

0190It is advantageous if a machine parameter is time-dependent, in particular if it comprises a variable G4a characterizing the decreasing battery voltage of the battery-backed memory and a second continuously monotonously decreasing variable G4b or the respective complements of the variables G4a and G4b.

0191It is further provided in a variant that the second, continuously monotonically decreasing variable G4b is the complement of the number of pieces or a continuously monotonically decreasing, time-dependent variable.

0192On the one hand, it is provided in a variant that the continuously monotonically decreasing quantity is a numerical value corresponding to the next inspection date (INS) and a continuously monotonously decreasing time-dependent quantity.

0193On the other hand, it is envisaged that a continuously monotonically increasing quantity includes the date or the number of pieces determined during the last inspection.

0194As has already been explained in more detail, it is advantageous if the control device 6 provides part of a quantity G0, G1 which characterizes the user of the franking machine in order to form third contiguous digits of the combination number KOZ1.

0195In sub-step 451, the memory areas T are preferably_w the top 10 digits of the combination number KOZ1 for the TIME data (size G4) and the bottom 4 digits for the postage value (size G3) are provided. This results in a combination number with 14 digits, which would then have to be encrypted. When using the DES algorithm, a maximum of 8 bytes, ie 16 digits, can be encrypted at once. This means that the combination number KOZ1 can be supplemented by a further size in the direction of the least significant digits. For example, the supplementary part can be part of the serial number SN or the number WRN of the advertising slogan frame or the byte which is selected from the data record of the advertising slogan frame as a function of a further size.

0196This combination number KOZ1 can be encoded in a sub-step 452 in about 210 ms into a crypto number KRZ1, a number of further steps known per se taking place here. Then, in sub-step 453, the crypto number KRZ1 is to be converted into a corresponding symbol row on the basis of a predetermined marking list stored in the memory areas M of the non-volatile working memory 5. In particular, the increased information density that is so advantageous for later printing can be achieved here.

0197Even if a set of 10 symbols - shown in FIG. 3f - is used, i.e. without an increase in the information density compared to the crypto number KRZ1, but two rows of markings (next to each other or one below the other) were printed, further symbols could remain with which further information could be displayed unencrypted or encrypted. It is then preferably information that does not change or hardly changes, and only needs to be encrypted once and converted into a series of symbols. This is preferably the size G5, ie inspection data (INS), for example the date of the last inspection or the rest of the serial number SN or SN and the byte of the data record of the advertising slogan frame, which was not included in the first combination number KOZ1, or. selected predetermined parts thereof. In FIG. 3c, a row with a total of 20 symbols is depicted in windows FE6 and FE10, arranged here orthogonally to one another, with which, for example, the total of 8 bytes, ie 16 digits, the crypto number KRZ1 and further information may be unencrypted or in some other way can be played back encrypted.

0198A second variant with a step 45b in addition to step 45a differs from the first variant in other output or input variables which have to be considered in the same way. In the second variant, a row of marking symbols is generated in two steps 45b and 45a, step 45b being carried out analogously to step 45a.

0199In a first sub-step 450 of the step 45 carried out by the control device 6, it is checked whether a flag has been set in order to cause the sub-steps 45b and / or 45a to be carried out, that in the sub-step 45b at least the other part of the user the second combination number KOZ2, which characterizes the franking machine G0, G1, then encrypted to a second crypto number KRZ2 and then converted into at least one second row of marking symbols MSR2 using a second set of symbols SSY2.

0200Compared to sub-step 451, a combination number KOZ2 is formed in sub-step 455, wherein in particular the sizes for other parts of the serial number, for advertising cliché (frame) number, and other sizes can be included. As in sub-step 452, a crypto number KOZ2 is formed in sub-step 456. In sub-step 457, the transformation into a series of marking symbols then takes place, which is temporarily stored in non-volatile manner in sub-step 458.

0201This is followed by sub-step 45a, which comprises sub-steps 451 to 453. If necessary, this can be connected by a sub-step 454. Then point c₃ reached.

0202In spite of the DES algorithm being used twice, a time saving nevertheless occurs because in a first sub-step 450 there is an evaluation as to whether the selected quantities required for the formation of the marking symbol series in sub-step 45b have been changed by an input. In the case of new input of selected special sizes, a flag would be set in step 44 and would be taken into account in the subsequent formation of data for a new series of marking symbols in order to process step 45b here. However, if this is not the case, it is possible to fall back on marking symbol rows which have already been formed and are stored in a non-volatile manner in a memory area 458 or parts of the marking symbol row.

0203In one embodiment variant, an encryption algorithm other than the DES is used in sub-step 456 to save time.

0204In an advantageous embodiment variant, a transformation is carried out in sub-step 453 of the first variant or in sub-step 457 of the second variant in order to additionally increase the information density of the marking symbol series compared to the crypto number KRZ1 or KRZ2. For example, in the case of a crypto number with 16 digits, a set of 22 symbols is now used to represent the information by means of only 12 digits - in the manner shown in FIG. 3b. For two crypto numbers, the row of marking symbols shown there must be doubled. This can be done by means of a further marking symbol row lying parallel to the marking symbol row shown in FIG. 3b.

0205Correspondingly, it can also be shown that only a symbol set comprising 14 symbols is required for a marking symbol row of 14 digits. The previously described check in the postal authority of mail items having such marking symbol rows can consequently - after the second evaluation variant - by transforming the marking symbol row back into crypto numbers KRZ1 or KRZ2, and then decrypting them to combination numbers KOZ1 if necessary. KOZ2, the individual sizes of which are compared with the sizes openly printed on the postal matter in the franking image, are carried out.

0206A row of marking symbols - as has been shown in FIG. 3a - is designed for 10 digits and can represent a crypto number KRZ1 if the symbol set has 40 symbols. Here, fully automated input and evaluation is useful - in order to avoid subjective errors by the examiner when recognizing the symbols.

0207In a step following step 45, the data of a data set for the marking symbol row are then embedded in the remaining pixel data after their decompression. According to the invention, two different options are provided for this. One possibility is explained in more detail with reference to FIG. 11 and another with reference to FIG. 13.

0208FIG. 11 explains step 46 in FIG. 5 in particular. In a sub-step 4660, window characteristic values ​​Z_k and T_k predefined for changed window data, the window change number p 'is determined and a window counter variable q is set to zero. In a sub-step 4661 it is evaluated whether the window count variable q is equal to the window change number p '. Then the point would be d₃ and thus the next step 47 has already been reached. However, this path is not regularly followed at the beginning, since the monotonously increasing size constantly creates new rows of marking symbols for each print.

0209Otherwise, if a change has been made, the process branches to sub-step 4662 in order to enter window characteristic values ​​corresponding to the changed windows and to set initial conditions.

0210In a sub-step 4663, a new source address for the data of the data record of the window FEk currently being processed is generated, in order to transfer a byte of the coded window data of type 2 from the memory area B in the next sub-step 4664_k to load into registers of the non-volatile memory 7a and to detect control characters.

0211In a sub-step 4665, the window column run length becomes Y_k around the window column run length variable W_k incremented, which is still zero here. Then a check is carried out for control characters for color changes (sub-step 4666) and, if necessary, branching back to sub-step 4663 or a search for control characters for the end of column (sub-step 4667). If successful, branch is made to sub-step 4669 and the window column counter P_k elevated. Otherwise, the next sub-step 4668 is to decode the control code and convert the called byte into decompressed binary window pixel data of type 2.

0212In sub-step 4670 it is then checked whether all the columns of the window have been processed. If this is the case, you branch to sub-step 4671 and the column run length Y_k of the window FEk is stored in the memory 7b and branched back to the sub-step 4673. If it is recognized in sub-step 4670 that not all the columns have been processed, then sub-step 4672, whereby the window characteristic value Y_k and the color flip-flop is reset to zero, branched back to sub-step 4663. In the next sub-step 4668, a decoding of the control code and a conversion of the called byte into decompressed binary window pixel data of type 2 must then be carried out again.

0213After sub-step 4673, where the characteristic values ​​of the next changed window are called, a branch is made back to sub-step 4661. When processing all change windows, point d₃ reached.

0214The print routine shown in FIG. 12 for assembling data from the pixel memory areas I and II runs when a print request is recognized in step 47 and data has been loaded in a sub-step 471 (not shown in FIG. 5).

0215In sub-step 471, the end address Z_{The End} loaded, the running address Z (running variable) to the value of the source address Z₀ in area I of the pixel memory 7c, the window column counter P_k to the respective value corresponding to the stored window column variable T_kwho have favourited Window bit count lengths X_k to the respective value corresponding to the stored window column run length Y_k set and the destination addresses Z_k for k = p windows and the total run length R for a printing column s_k loaded. The pressure column has N pressure elements.

0216Then, when you reach point e₁ At the beginning of step 48, several sub-steps are running. First, in a sub-step 481, the register 15 of the printer controller 14 is loaded serially bit by bit from the area I of the pixel memory 7c with binary print column data, which are called up with the address Z, and the window counter h is set to a number that corresponds to the number of windows increased by one p corresponds. In sub-step 482 a window counter h is decremented, which outputs window numbers k one after the other, whereupon in sub-step 483 the address Z reached in the pixel memory with the window start address Z_k of the window FE_k is compared. If the comparison is positive and a window start address is reached, a branch is made to sub-step 489, which in turn consists of sub-steps 4891 to 4895. Otherwise, branch to sub-step 484.

0217In sub-step 4891, a first bit from the area II of the pixel memory 7c is serial for the window FE_k the binary window pixel data is loaded into the register 15, the address Z and the bit count variable 1 being incremented in the sub-step 4892 and the window bit count length X_k is decremented. In a sub-step 4893, if not all bits corresponding to the window column run length Y_k are loaded, further bits from area II are loaded. Otherwise, a branch is made to sub-step 4894, the window start address Z_k for the addressing of the next window column increased by the total length R and the window column counter P_k is decremented. At the same time, the original window bit count length X_k corresponding to the window column run length Y_k restored.

0218Sub-step 4895 then checks whether all the window columns have been processed. If this is the case, then the start address Z_k for the corresponding window FE_k set to zero or an address which lies outside the pixel memory area I. Otherwise and after sub-step 4896, point e₁ branches.

0219In sub-step 484, it is checked whether all window start addresses have been queried. If this has taken place, a branch is made to sub-step 485 in order to increment the current address Z. If this has not yet taken place, a branch is made back to sub-step 481 in order to continue to decrement window counter h until the next window start address has been found or until window counter h becomes zero in sub-step 484.

0220In sub-step 486 it is checked whether all the data for the column to be printed s_k are loaded in register 15. If this is not yet the case, the bit count variable 1 is incremented in sub-step 488 in order to go to point e₁ to return and then (in sub-step 481) to load the next bit addressed with the address Z from the pixel memory area into the register 15.

0221However, if register 15 is full, the column is printed out in sub-step 487. Then, in a step 50 - already shown in FIG. 5 - it is determined whether all the pixel data of the pixel memory areas I and II have been printed out, that is to say the item of mail has been franked completely. If this is the case, then point f₁ reached. Otherwise, a branch is made to sub-step 501 and the bit count variable 1 is reset to zero in order then to point e₁ to branch back. Now the next print column can be created.

0222The printing routine for the compilation of data taken from only one pixel memory area I and working memory areas is explained in more detail with reference to FIG. 13. After pressure request, which is determined in step 47 - shown in FIG. 6 -, a sub-step 471, as already explained in connection with FIG. 12, takes place immediately around point e₂ to reach. Step 49, which is now beginning - already shown in FIG. 6 - comprises sub-steps 491 to 497 and sub-steps 4990 to 4999. Sub-steps 491 to 497 run with the same result in the same order as sub-steps 481 to 487 have already been explained in connection with FIG. Merely in sub-step 493, a branch is made to sub-step 4990 in order to reset a color flip-flop to g: = 0, whereupon the process of decompressing the coded window data of type 2 by column, which was explained in connection with FIG. 6, is initiated with sub-step 4991 becomes. Here there is a color change already explained - in connection with FIG. 7 - when evaluating the type 2 window pixel data to be converted, so that the first hexadecimal data of the data set called up are evaluated as colored, for example. The source address is incremented. The compressed window data for the window FE is then loaded_k of type 2, especially for the marking data, from which (in the corresponding sub-storage areas B_j stored) predetermined data record in the registers 200 of the volatile main memory 7a in sub-step 4992. A hexadecimal number "QQ" corresponds to one byte.

0223The control code is also detected here. If a window column is to be printed that begins with non-colored, ie not to be printed, pixels, the control code "color change" would appear first in the data record. Thus, in sub-step 4993, there is a return to sub-step 4991 to carry out the color change. Otherwise, branch to sub-step 4994. In sub-step 4994, it is determined whether there is a "column end" control code. If this is not yet the case, the register content must be decoded and thus decompressed. For each run length-coded hexadecimal numerical value, there is a series of binary pixel data in the character memory (CSP) 9, which can be called up accordingly on the basis of the hexadecimal number loaded in the volatile working memory 7a. This is done in sub-step 4995, after which the decompressed window pixel data for a column of the windows FE_j of type 2 are loaded serially into the print register 15 of the printer controller 14.

0224The address is then incremented in sub-step 4996 and a corresponding next hexadecimal number is selected in the data record, which is in the non-volatile main memory 5 in sub-area B₅ is stored, and the bits converted during the decoding of the run length coding are determined by a window column run length variable W_j to form with which the destination address is incremented. The new destination address for reading is thus generated. and branching back to sub-step 4991.

0225If the end of the column is reached, follow the sub-steps 4997 to 4999, then to point e₂ to branch back. The sub-steps 4998 and 4999 run similarly to the sub-steps 4895 and 4894 shown in FIG.

0226In sub-step 497, the print column that has been loaded is printed. The sub-steps 491 to 497 run similarly to the sub-steps 481 to 487 shown in FIG.

0227In addition to less mechanical effort, there is a high printing speed with a large number of variable print image data to be embedded in a stored fixed print image.

0228In particular, the advantageous variants have been explained in more detail, but it is entirely possible in the case of faster hardware to change the sequence of the method steps in order to also quickly generate a security imprint.

0229In step 47, if a print request has been made, step 48 containing a print routine is waited for and if a print request has not yet taken place, the print request is waiting in a waiting loop by going directly back to the beginning of step 47 in FIGS. 5 and 6, respectively According to the invention, this has a further advantage in terms of time, since the DES algorithm is not permanently generated anew. The next recordable point in time after generation of the marking symbol row can already trigger printing. However, as mentioned, other branches can also be made.

0230Likewise, in another variant, step 45 can be placed between steps 53 and 54. In step 54 following step 45, the data of a data set for the marking symbol row are then embedded in the remaining pixel data of the pixel memory area I after their decompression. A further pixel memory area is then not required.

0231Another opposite variant stores only the frame pixel data in the pixel memory area and embeds all window pixel data immediately in the corresponding columns read into the print register 15, without the need for a pixel memory for window data in between.

0232In one variant, without the automatic editing of cliché text parts, memory area A_i to be dispensed with. Instead, the unchangeable image information is stored in an ONLY read memory, for example in the program memory (ROM) 11. When the unchangeable image information is decoded, this ONLY read memory 11 is accessed, so that the intermediate storage can be omitted.

0233The invention is not limited to the present embodiment.