Glyph contour fine-tuning-based invisible anti-counterfeiting seal layout method
By fine-tuning the outline data of seal characters, an invisible anti-counterfeiting font library is generated, which solves the problem that existing seal anti-counterfeiting features are easily counterfeited, and achieves a seal anti-counterfeiting effect with high concealment and low cost.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- 邱律
- Filing Date
- 2026-02-24
- Publication Date
- 2026-05-29
AI Technical Summary
Existing anti-counterfeiting measures for seals have obvious anti-counterfeiting features and are easily imitated, affecting the aesthetics and solemnity of the seals. Moreover, with the popularization of high-precision scanning equipment, cases of seal forgery are frequent.
By making very minor additions and movements to the outline data of characters in the standard character set, a unique and concealed anti-counterfeiting character set is generated. Fine-tuning is performed at the non-intersecting stroke contact points to ensure that the anti-counterfeiting features are difficult to detect.
It achieves the embedding of invisible anti-counterfeiting features, which increases the difficulty of anti-counterfeiting of seals and reduces the success rate of counterfeiting, while not affecting the visual recognition and solemnity of seals. It can also be directly integrated into the existing seal production process, reducing implementation costs.
Smart Images
Figure CN122113891A_ABST
Abstract
Description
Technical Field
[0001] This invention relates to the field of seal anti-counterfeiting and font processing technology, specifically to an invisible anti-counterfeiting seal layout method based on fine-tuning of character outlines, the resulting anti-counterfeiting font library, anti-counterfeiting seal drafts, and anti-counterfeiting document layout method. Background Technology
[0002] As an important credential for state administrative organs, enterprises, public institutions, and social organizations to exercise their powers and conduct social activities, the authenticity and uniqueness of seals are of paramount importance. With the widespread use of computer typesetting and machine production, existing technologies offer several solutions for achieving anti-counterfeiting features in seals. For example, the anti-counterfeiting methods disclosed in existing technologies such as CN201510320123.1, CN201410848432.X, CN201310019021.2, and CN201910538678.0 mainly employ common techniques such as adding intermittent white lines to the seal's border and text during the design and typesetting process. However, these methods result in overly obvious visual anti-counterfeiting features, making them easy for counterfeiters to observe and copy, thus limiting their lifespan. Secondly, these additional features can easily disrupt the structural aesthetics of the original seal's font and its overall solemnity and seriousness. Furthermore, with the widespread use of high-precision scanning and seal-making equipment, the imitation of physical features has become increasingly easy, leading to frequent cases of seal forgery and posing significant risks to social management and economic order. Therefore, there is an urgent need in this field for a new technology that can maintain the standardization of the seal's design and imprint while embedding difficult-to-detect and counterfeit anti-counterfeiting features. Summary of the Invention
[0003] The present invention aims to overcome the shortcomings of existing technologies and solve the technical problems of traditional seal anti-counterfeiting methods, such as obvious anti-counterfeiting features, easy imitation, and impact on the aesthetics and solemnity of seals. It provides a seal anti-counterfeiting method that is easy to integrate into the existing seal production process and has highly concealed anti-counterfeiting features.
[0004] To address the aforementioned technical problems, this invention proposes a method for typesetting invisible anti-counterfeiting seals based on fine-tuning of character outlines. The core of this method lies in making minute additions and movements to the stroke connections of characters in a standard font library, generating a unique and visually indistinguishable "twin" anti-counterfeiting font library. This font library can be directly used in existing typesetting software to create seals with invisible features.
[0005] The core innovations of the technical solution are: ① Fine-tuning at the non-intersecting stroke contact points to maintain the integrity of the character shape while ensuring anti-counterfeiting concealment; ② Unique anti-counterfeiting features for each character based on unique parameter mapping of the encoding; ③ Compatibility with existing typesetting software and seal-making processes, reducing implementation costs.
[0006] Definition of technical terms: "Contour node" refers to the fine nodes that appear on the edge of the character contour after performing the "Convert to Curve" operation on the characters in text state in design software such as CorelDraw, or after double-clicking on any selected character in font editing software such as FontCreator. Moving them can modify the shape of the character; "Outer frame side length of glyph" refers to the side length of the circumscribed rectangle of Chinese characters under the standard typesetting size, that is, the maximum value of the character height and width; "Non-crossing stroke contact connection" refers to the non-crossing contact of two strokes, such as the first and second strokes of the character "石", rather than the first and second strokes of the character "右". The latter is a cross-stroke connection, and the former is a non-crossing stroke connection. Description of the drawings
[0007] Figure 1 This is the general flowchart of the method of the present invention.
[0008] Figure 2 This is a schematic diagram for identifying contour nodes of the type where the horizontal stroke is on top and the vertical stroke is at the bottom (taking the character "丁" as an example).
[0009] Dashed box: Non-crossing contact connection area (horizontal stroke on top, vertical stroke at the bottom, only endpoint contact, no penetration); Arrow direction: Starting end of the vertical stroke (fine-tuning operation area); Text description: This figure corresponds to the first type of contact connection described in claim 1, and only fine-tunes the nodes at the starting end of the lower vertical stroke.
[0010] Figure 3 This is a schematic diagram for adding a new contour node.
[0011] Add a new node b below the original node a, and the distance between node b and node a is about 1 / 20 of the outer frame side length L of the glyph.
[0012] Figure 4 This is a schematic diagram for fine-tuning by moving a contour node.
[0013] Move the original node a to the left by a distance of about 1 / 30 of the outer frame side length L of the glyph.
[0014] Comparison of contour data before and after fine-tuning: Before fine-tuning, the coordinates of node a are (x1, y1), after fine-tuning, the coordinates of the newly added node b are (x1, y1 - L / 20), and the coordinates of node a after moving are (x1 - L / 30, y1).
[0015] Figure 5 This is Figure 4 An enlarged display effect diagram of 10 times the fine-tuning area shown.
[0016] Figure 6Schematic diagram of the fine-tuning process for contour nodes where the slanting stroke is on top and the vertical stroke is at the bottom and they are in contact and connected (taking the character "千" as an example).
[0017] Dotted-line box: Area where the slanting stroke is on top and the vertical stroke is at the bottom and they are in contact and connected (non-crossing); Node processing: First, add a new node b below the original node a, and the distance between node b and node a is 1 / 20 of the side length L of the outer frame of the character shape; then move the original node a to the left by a distance approximately equal to 1 / 30 of the side length L of the outer frame of the character shape.
[0018] Comparison of contour data before and after fine-tuning: Before fine-tuning, the coordinates of node a are (x1, y1), after fine-tuning, the coordinates of the newly added node b are (x1, y1 - L / 20), and the coordinates of node a after moving are (x1 - L / 30, y1).
[0019] Text description: This figure corresponds to the second type of contact and connection described in claim 1. The fine-tuning only acts on the starting end of the vertical stroke, maintaining the integrity of the slanting stroke and the vertical stroke.
[0020] Figure 7 Schematic diagram of the fine-tuning process for contour nodes where the horizontal stroke is on top and the slanting stroke is at the bottom and they are in contact and connected (taking the character "石" as an example).
[0021] Dotted-line box: Area where the horizontal stroke is on top and the slanting stroke is at the bottom and they are in contact and connected (non-crossing); Node processing: First, add a new node b below the original node a, and the distance between node b and node a is 1 / 20 of the side length L of the outer frame of the character shape; then move the original node a to the left by a distance approximately equal to 1 / 30 of the side length L of the outer frame of the character shape.
[0022] Comparison of contour data before and after fine-tuning: Before fine-tuning, the coordinates of node a are (x1, y1), after fine-tuning, the coordinates of the newly added node b are (x1, y1 - L / 20), and the coordinates of node a after moving are (x1 - L / 30, y1).
[0023] Text description: This figure corresponds to the third type of contact and connection described in claim 1. The fine-tuning only acts on the starting end of the slanting stroke, maintaining the integrity of the horizontal stroke and the slanting stroke.
[0024] Figure 8 Schematic diagram of the fine-tuning process for contour nodes where the slanting stroke is on top and the slanting stroke is at the bottom and they are in contact and connected (taking the character "乔" as an example).
[0025] Dotted-line box: Area where the slanting stroke is on top and the slanting stroke is in contact and connected (non-crossing); Node processing: First, add a new node b below the original node a, and the distance between node b and node a is approximately 1 / 20 of the side length L of the outer frame of the character shape; then move the original node a to the left by a distance approximately equal to 1 / 30 of the side length L of the outer frame of the character shape.
[0026] Comparison of contour data before and after fine-tuning: Before fine-tuning, the coordinates of node a are (x1, y1). After fine-tuning, the coordinates of the newly added node b are (x1, y1 - L / 20), and the coordinates of node a after movement are (x1 - L / 30, y1).
[0027] Text description: This figure corresponds to the ④th type of contact connection described in claim 1. The fine-tuning only acts on the starting end of the downward slanting stroke, keeping the integrity of the horizontal stroke and the slanting stroke.
[0028] Figure 9 Schematic diagram of the contour node fine-tuning process for the contact connection where the vertical stroke is on the left and the horizontal stroke is on the right (taking the character '口' as an example).
[0029] Dotted-line box: The contact connection area where the vertical stroke is on the left and the horizontal stroke is on the right (non-crossing); Arrow direction: The starting end of the horizontal stroke (fine-tuning operation area); Node processing: First, add a new node b to the right of the original node a. The distance between node b and node a is approximately 1 / 20 of the side length L of the character outline box. Then, move the original node a upward by a distance approximately 1 / 30 of the side length L of the character outline box.
[0030] Comparison of contour data before and after fine-tuning: Before fine-tuning, the coordinates of node a are (x1, y1). After fine-tuning, the coordinates of the newly added node b are (x1 + L / 20, y1), and the coordinates of node a after movement are (x1, y1 + L / 30).
[0031] Text description: This figure corresponds to the ⑤th type of contact connection described in claim 1. Only the starting-end node of the horizontal stroke on the right is fine-tuned.
[0032] Figure 10 Schematic diagram of the contour node fine-tuning process for the contact connection where the slanting stroke is on the left and the horizontal stroke is on the right (taking the character '月' as an example).
[0033] Dotted-line box: The contact connection area where the slanting stroke is on the left and the horizontal stroke is on the right (non-crossing); Node processing: First, add a new node b to the right of the original node a. The distance between node b and node a is approximately 1 / 20 of the side length L of the character outline box. Then, move the original node a upward by a distance approximately 1 / 30 of the side length L of the character outline box.
[0034] Comparison of contour data before and after fine-tuning: Before fine-tuning, the coordinates of node a are (x1, y1). After fine-tuning, the coordinates of the newly added node b are (x1 + L / 20, y1), and the coordinates of node a after movement are (x1, y1 + L / 30).
[0035] Text description: This figure corresponds to the ⑥th type of contact connection described in claim 1. The fine-tuning only acts on the starting end of the horizontal stroke and does not damage the structure of the slanting stroke and the horizontal stroke.
[0036] Figure 11 Examples of the comparison effects before and after comprehensive fine-tuning for multiple Chinese characters with different structures (such as "field", "and", "happy", "shop", etc.).
[0037] The dashed-line box is the area where fine-tuning can be performed.
[0038] Figure 12 (Summary diagram of six types of contact connections): Figure name: Summary of six non-crossing stroke contact connection types; Each connection area is marked with a dashed-line box, and their corresponding category numbers in claim 1 are explained as follows: Left in the first row: The character "ding" (Category ①: horizontal on top - vertical below); Right in the first row: The character "qian" (Category ②: left-falling stroke on top - vertical below); Left in the second row: The character "shi" (Category ③: horizontal on top - left-falling stroke below); Right in the second row: The character "yue" (Category ④: left-falling stroke on the left - horizontal on the right); Left in the third row: The character "kou" (Category ⑤: vertical on the left - horizontal on the right); Right in the third row: The character "qiao" (Category ⑥, left-falling stroke on top - left-falling stroke below) Specific implementation manners
[0039] The following combines the accompanying drawings to provide a detailed and complete description of the present invention so that those skilled in the art can implement it.
[0040] As Figure 1 shown, the overall process includes: obtaining contour data, identifying connection points, performing fine-tuning, generating a font library, and typesetting applications.
[0041] Regarding step S2 (identification): The present invention focuses on the connection points of strokes because the contour nodes are relatively concentrated here. Performing fine-tuning can not only implant features but also best maintain the stability of the overall structure of the glyph. As Figure 2 shown, taking the character "ding" as an example, the dashed-line box pointed by the arrow is the connection transition area between the horizontal and vertical strokes, which is a typical position to be processed.
[0042] Regarding step S3 (fine-tuning operation): This is the core of the present invention. The fine-tuning is only performed within a very small range.
[0043] Node addition: As Figure 3 shown, a node b is added below the original node a on the selected contour line.
[0044] Node movement: As Figure 4 shown, the original node a is directly translated to the left.
[0045] Regarding the fine-tuning effect and examples: Figure 5 shows Figure 4 the magnified effect of the area showing the movement of the nodes.
[0046] Figure 6 The figure shows the application at the connection of the left-falling stroke and the vertical stroke (taking 'qian' as an example). The standard glyph is at the upper left corner, and the fine-tuned glyph is at the lower left corner. It can be seen that there are changes only in the extremely small area marked by the dotted square box, and the overall appearance of the character remains unchanged.
[0047] Figure 7 shows the application at the connection of the horizontal stroke and the left-falling stroke (taking'shi' as an example). The standard glyph is at the upper left corner, and the fine-tuned glyph is at the lower left corner. It can be seen that there are changes only in the extremely small area marked by the dotted square box, and the overall appearance of the character remains unchanged.
[0048] Figure 8 shows the application at the connection of two left-falling strokes (taking 'qiao' as an example). The standard glyph is at the upper left corner, and the fine-tuned glyph is at the lower left corner. It can be seen that there are changes only in the extremely small area marked by the dotted square box, and the overall appearance of the character remains unchanged.
[0049] Figure 9 shows the application at the connection of the vertical stroke and the horizontal stroke (taking 'kou' as an example). The standard glyph is at the upper left corner, and the fine-tuned glyph is at the lower left corner. It can be seen that there are changes only in the extremely small area marked by the dotted square box, and the overall appearance of the character remains unchanged.
[0050] Figure 10 shows the application at the connection of the left-falling stroke and the horizontal stroke (taking 'yue' as an example). The standard glyph is at the upper left corner, and the fine-tuned glyph is at the lower left corner. It can be seen that there are changes only in the extremely small area marked by the dotted square box, and the overall appearance of the character remains unchanged.
[0051] Figure 11 Comprehensively shows the fine-tuning effects of multiple glyphs such as 'tian', 'he', 'xi', 'pu', etc., proving that the method of the present invention has wide character applicability.
[0052] Generation process of the anti-counterfeiting font library Using font editing software such as FontCreator, import the standard GB2312 font library, and after adjusting the nodes according to step S3, generate a new TrueType or OpenType format font file for all characters, that is, generate the anti-counterfeiting font library.
[0053] Regarding the application After the seal-making practitioners install the anti-counterfeiting font library, they can call this anti-counterfeiting font library for design and typesetting in various professional seal software or other typesetting design software such as CorelDRAW and Word (step S5) just like using an ordinary font library. The seal text made thereby contains hidden microscopic features.
[0054] Regarding the expansion of the scope of protection Since the generated anti-counterfeiting font is a standard font file, its application is naturally not limited to seals. As described in claim 7, it can also be used for the design and typesetting of important documents, certificates, invoices, etc., that require similar anti-counterfeiting functions. As long as the method implemented by others falls within the scope of claims 1-4, regardless of whether the generated font is ultimately used for seals or documents, it is within the protection scope of this invention.
[0055] Beneficial effects
[0056] The present invention achieves the following beneficial effects through the above-mentioned subtle and precise contour adjustment method: strong concealment: the anti-counterfeiting features are embedded at the stroke connection, the micro-deformation size is extremely small, and it is extremely difficult to detect with the naked eye, without affecting the normal visual recognition and solemnity of the seal.
[0057] High difficulty of counterfeiting: Counterfeiters cannot determine the specific locations and parameters of modifications through ordinary observation or low-precision scanning. Even if they realize that there are micro-modifications, the cost and difficulty of accurately replicating all features are extremely high due to the diversity and specificity of the modification rules.
[0058] Convenient authentication: Once the modified parameters of the original anti-counterfeiting character library are registered, authenticators can quickly locate comparison points using magnification equipment or image feature extraction software to achieve scientific and objective authentication.
[0059] Good compatibility: This method is based on digital font library operation and can be directly integrated into the existing computer typesetting and laser seal making process without changing the existing seal material and production process, resulting in low implementation cost.
[0060] Tests showed that the anti-counterfeiting features of this invention had a 0% recognition rate under naked-eye observation and a 100% recognition rate under a 40x optical microscope, significantly reducing the success rate of counterfeiting.
Claims
1. Claim 1 (Core Independent Claim, Method Type): A method for typesetting invisible anti-counterfeiting seals based on fine-tuning of character outlines, characterized in that... Includes the following steps: S1: Obtain the outline data of ordinary glyphs, wherein the ordinary glyphs are Chinese character glyphs that are uniquely mapped and assigned based on the GB2312 encoding or Unicode encoding of the characters, and their outline data are vector outline data; S2: Identify the outline node area of non-intersecting stroke contact connections in the character shape. The stroke contact connection refers to the point where only the endpoints touch, without the strokes penetrating each other, and each stroke remains independent and complete. It is divided into the following six types: ① Horizontal stroke above and vertical stroke below; ② Left-falling stroke above and vertical stroke below; ③ Horizontal stroke above and left-falling stroke below; ④ Left-falling stroke above and left-falling stroke below; ⑤ Vertical stroke on the left and horizontal stroke on the right; ⑥ Left-falling stroke on the left and horizontal stroke on the right. The contact connection does not destroy the integrity of any stroke. S3: Only perform the operation of adding and moving contour nodes in the area where the starting point of the stroke below / right of the contact connection is located, so as to introduce a slight deformation that is not directly perceptible to the eye; the number of newly added nodes is 1, located in the vertical direction of the line connecting the two existing adjacent contour nodes. The vertical direction is perpendicular to the normal direction of the line connecting the two existing adjacent contour nodes, and it is located on the line segment below / right. The distance between it and the line connecting the original nodes is 1 / 15 to 1 / 20 of the side length of the character frame. Then, move the existing node that is closest to it to the left / up. Moving to the left is applicable to the starting point of the lower stroke, and moving to the up is applicable to the starting point of the right stroke. The moving distance is 1 / 20 to 1 / 30 of the side length of the character frame. 2.S4: Generate an anti-counterfeiting font library based on the modified outline data. The anti-counterfeiting font library is in TrueType or OpenType format and contains all Chinese characters in the character set of the GB2312 standard. S5: Use the anti-counterfeiting font library to design the layout of the seal design and generate a seal pattern with invisible anti-counterfeiting features.
3. Claim 2 (dependent claim, defining the uniqueness of the font library): The method according to claim 1, characterized in that, The parameter combinations for adding and moving nodes in step S3 are uniquely mapped and assigned based on the GB2312 encoding or Unicode encoding of the character, and the fine-tuning parameter combinations corresponding to different characters are not repeated.
4. Claim 3 (dependent claim, detailing font compatibility): The method according to claim 1, characterized in that, The anti-counterfeiting font library generated in step S4 is compatible with mainstream typesetting software, including CorelDRAW, Adobe Illustrator, AutoCAD, Word, and professional seal making software.
5. Claim 4 (Independent claim, anti-counterfeiting font type): An anti-counterfeiting font library, characterized in that, Generated by the method described in claims 1-3, each non-crossing stroke contact connection of each character in the anti-counterfeiting font library (the six types described in claim 1) has a unique invisible anti-counterfeiting feature of "one new node" and "only one node at the starting point of the lower / right stroke moves".
6. Claim 5 (Independent claim, anti-counterfeiting seal / imprint type): A type of anti-counterfeiting seal design, characterized in that, The typesetting is done using the anti-counterfeiting font library as described in claim 4. The non-intersecting strokes of the characters in the printed manuscript have invisible anti-counterfeiting features. These features can be extracted and identified under standard lighting conditions (such as visible light, 500-700nm wavelength) using an optical microscope with a magnification of ≥40x.
7. Claim 6 (dependent claim, supplementary manuscript identification rules): According to claim 5, the anti-counterfeiting seal design is characterized in that, During the authentication process, the coordinates of the contour nodes at the contact points of the strokes are extracted using an optical microscope and compared with the original fine-tuning parameters in the filing. If the comparison error is ≤0.005mm, it is considered genuine. The comparison error is the Euclidean distance error between the extracted contour node coordinates and the original parameters in the filing. The original fine-tuning parameters in the filing include the position coordinates of the newly added nodes and the movement distance and direction of the original nodes.
8. Claim 7 (Independent claim, type of anti-counterfeiting document typesetting method): A method for formatting anti-counterfeiting documents, characterized in that, The anti-counterfeiting font library described in claim 4 is used to typeset the document content. The document includes certificates, invoices, contracts, official documents, etc. During typesetting, the number of new nodes at the contact connection of character strokes, the offset of node positions, the original node movement distance and direction, and other fine-tuning parameters are completely consistent with the corresponding parameters of the seal manuscript described in claim 5, so as to realize the anti-counterfeiting association verification between the document and the seal.
9. Claim 8 (Independent claim, derivative method of seal making): A method for typesetting an anti-counterfeiting seal, characterized by comprising the following steps: a: Generate the initial seal image using a standard font library; b: Extract the outline data of the Chinese characters in the initial seal image and identify the non-intersecting stroke contact connections (i.e., the six contact connection types described in claim 1). c: The node addition and movement method described in step S3 of claim 1 is adopted, and the parameters of node addition and movement (number of new nodes, distance, and movement distance of existing nodes) are similar to those in S3, and the starting end contour node at the contact connection is finely adjusted. d: Create a stamp based on the finely adjusted contour data.
10. Claim 9 (Independent claim, infringing product protection category): An anti-counterfeiting seal, characterized in that, Made by the method described in claim 1 or 8, the contact connection of the Chinese character strokes of the seal (the six types described in claim 1) has the following invisible anti-counterfeiting features: "the number of newly added nodes is 1", "only one node at the starting point of the lower / right stroke moves a distance of 1 / 20 to 1 / 30 of the side length of the character's outer frame", and "the direction of movement is to the left (starting point of the lower stroke) or upward (starting point of the right stroke)", and these features do not destroy the integrity of any stroke.