JP2606064B2 - Image processing device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an image processing apparatus for processing a document to form an image on a recording medium.
The present invention relates to an image processing apparatus provided with an abuse copy prevention function for preventing a color document such as a securities document from being faithfully copied.

[0002]

2. Description of the Related Art In recent years, with the improvement of the performance of color copiers, it is necessary to develop a copier having a function of preventing copying of securities such as banknotes, stock certificates, bonds, commuter pass tickets, event tickets, and cash vouchers. The nature is higher. The technology related to the copy protection function of conventional copiers is roughly divided into
The technique is divided into a technique of providing a function of preventing normal copying on the document side and a technique of providing a function of detecting a copy-inhibited document by the image reading / detecting device and preventing a normal copying operation. The function of preventing normal copying on the original side includes, for example, mixing a metal powder into the original to form a copy image based on a metal powder other than the original image by the metal powder of the original image surface irradiation lamp; Moire generated by applying a halftone dot at the time of copying to the background pattern of the recorded image, processed using holography, or using fluorescent color that cannot form a clear image by copying on ink, copying using selenium photoreceptor Techniques such as those utilizing blue ink which is difficult to reproduce on a machine are known. The latter technology, which detects a copy-inhibited original with the image reading / detecting device and provides a function to prevent normal copying operation, compares the read data of the original with the basic data in the memory to determine whether the original is good for copying. And a method of performing processing such as prohibiting copying, making the output paper unfixed, and changing the output state of the paper from normal is known.

[0003]

However, any of the above-mentioned prior art technologies for preventing abuse copying of originals have advantages and disadvantages.
Not widely spread. In addition, the normal copy protection function of the image reading / detecting device requires a memory having an enormous capacity for storing basic data of a specific document and a means for comparing and judging the read document image. There was a drawback that it became expensive. Therefore, an object of the present invention is to provide an image processing apparatus that can be installed in all color image processing apparatuses and that can detect a circular image at a relatively low cost, and more specifically, an image processing apparatus that can determine a bill or the like.

[0004]

The above object of the present invention is achieved by the following constitution. That is, in an image processing apparatus that reads a document image in units of pixels with a scanner, performs image processing on the read image, and outputs the read image, a specific color detection unit that detects a specific color of the document image, and a specific color detection unit that detects the specific color. A first predetermined distance pitch line image detecting means for detecting specific color images corresponding to both ends of a first predetermined distance corresponding to a diameter of a circle on a line in the main scanning direction with respect to the obtained image; When the specific color image is detected by the first predetermined distance pitch line image detecting means, on a line separated from the center position of the circle having the diameter of the first predetermined distance by the set distance in the sub-scanning direction, A second predetermined distance pitch line image detecting means for detecting an intersection of the line and the circle; and a second predetermined distance pitch line detecting means for detecting the second predetermined distance pitch line. Outer shell of the detected specific color image by the detection means the image processing apparatus provided with a specific color circular image determination mechanism consisting of determining the specific color of the circular image determination means and is formed from a circular image, or,

[0005] In an image processing apparatus for reading a document image in a pixel unit with a scanner, image processing the read image, and outputting the processed image, a specific color detecting means for detecting a specific color of the document image and a specific color detecting means. A first predetermined distance pitch line image detecting means for detecting a specific color image corresponding to both ends of a first predetermined distance corresponding to a diameter of a circle on a line in the main scanning direction with respect to the detected image; When the specific color image is detected by the pitch line image detecting means at the first predetermined distance, the pitch line image on the line separated from the center position of the circle having the diameter of the first predetermined distance by the set distance in the sub-scanning direction. A second predetermined distance pitch line image detecting means for detecting an intersection of a line and the circle, and the number of pixels in a predetermined area in a set of lines detected by the second predetermined distance pitch line detecting means is When comparing and judging that the image is within a specific number range stored in the storage means, it is determined that the outline of the image of the specific color detected by the series of detection means is determined to be formed from a specific circular image. The image processing apparatus is provided with a specific color specific circular image determining mechanism including a specific color circular image determining unit.

Here, the number of pixels in a predetermined area in the set of lines detected by the second predetermined distance pitch line detecting means is within a specific number range previously stored in the storage means. When the determination is made, the outline of the image of the specific color detected by the series of detection means is determined to be formed from the specific circular image. If the number of ON / OFF changes of pixels in a predetermined area in a set of lines detected by the distance pitch line detecting means is compared with and determined to be within a specific number range previously stored in the storage means, It is also possible to use specific circular image determining means of a specific color that determines that the outline of the image of the specific color detected by the detecting means is formed from a specific circular image.

In the image processing apparatus, the specific color is red, and d = 2√ ｛between the first predetermined distance d ₀ , the second predetermined distance d, and the set distance L in the sub-scanning direction. ^{_{(d 0/2) 2 -L}} 2} ( _{where, d 0/2>L>} 0) relation holds for the the _{d 0} of the particular circular image substantially 1
If it is determined that it is 4.5 mm or 13.5 mm, it is determined that it is based on the red seal of the bill. Also,
A specific circular image determining mechanism for a specific color can be provided in an image output unit to which an image reading signal from an external scanner is input. The object of the present invention is also achieved by the following configuration. That is, the image processing apparatus includes a specific circular image determining mechanism for the specific color and a magnetic detector disposed in the platen cover for detecting magnetism on the document side.

[0008]

According to the first to sixth aspects of the present invention, the following effects are obtained. That is, the present invention is an image processing apparatus for detecting an image having a circular outline. Since a circular image can be read as a circular image irrespective of the direction in which the document is set on the document reading surface of the image processing apparatus, attention has been paid to the fact that a means for identifying the image can be configured relatively easily. Therefore, first, detects a pixel corresponding to both ends between a predetermined distance corresponding to a first predetermined distance pitch line image detection means of the circle on the main scanning direction line diameter (e.g. d ₀ mm) as shown in FIG. 2 And a second predetermined distance (for example, dmm) pitch line image detecting means on a line separated from the center position (x ₀ , y ₀ ) of the circle by a set distance (for example, Lmm) in the sub-scanning direction. in the intersection between the circle and the line _{(x 0 -d / 2, y} 0 -L) and (x
₀ + d / _2, y ₀ detects that there is an image corresponding to -L), between the _d 0 mm and Lmm and dmm 2
Equation (1) holds from the above. ^{_{d = 2√ {(d 0/}} 2) 2 -L 2} (1) _where the d 0/2>L> 0 pitch d satisfies the formula (1), said detecting specific color image of circular This assumption is correct. However, at this time, even the image in which the inside of the detected circular image area is filled with the specific color satisfies Expression (1).

Therefore, the number of ONs N within a predetermined distance (amm) from the center of the dmm pitch line in the circle is counted, and the number of ONs N corresponds to specific image data stored in the buffer memory in advance. If the numbers match,
The circular image of this specific color can be specified. Also,
This circular image can also be specified by counting the number of changes from on to off and from off to on in the same area.

[0010] bill red seal is assumed to be the specific image of the specific color, _{d 0} is 14.5 mm (bill surface) or 13.
If the number of ONs N on the line on which the dmm pitch line that can be arbitrarily selected is 5 mm (backside of the banknote) matches the number of red pixels of a character such as, for example, “Bank of Japan” in the banknote, the detected circular red The information can be determined to be a red seal on the bill. Here, the reason why the red pixel search position is shifted by Lmm from the center position (x ₀ , y ₀ ) of the circle in the sub-scanning direction is that, for example, a character is printed in a red circle on a line passing through the center of the red seal of a bill. This is because if L = 0, red pixels on a line where a dmm pitch line is detected may not be counted in some cases.

[0011]

Embodiments of the present invention will be described below with reference to the drawings. FIG. 21 shows an overall configuration diagram of a digital color copying machine as an example of an image processing apparatus to which the present embodiment is applied.
In the color copying machine shown in FIG. 21, a base machine 30 includes a platen glass 31 on which an original is placed, an image input device 32, an electric system control storage unit 33, an image output device 34, a paper tray 35, and a user interface (U / I) 36, and optionally, an edit pad 61,
Auto Document Feeder (ADF) 62, Sorter 6
3, and a film image reading device including a film projector (F / P) 64 and a mirror unit (M / U) 65.

The image input device 32 includes an imaging unit 37, a wire 38 for driving the imaging unit 37, a driving pulley 39, etc., and primary color B (blue), G (green), The image information of a color document read out using a CCD line sensor after being separated into R (red) colors is converted into a multi-tone digital image signal BGR and output to an image processing device. The image processing device is housed in the electrical system control housing unit 33, receives a BGR image signal, and performs various conversion, correction, and editing processes to improve color, gradation, definition, other image quality, and reproducibility. Are converted into primary colors Y (yellow), M (magenta), C (cyan), and K (black or black) of the toner based on the processed signal, and a gradation toner signal of a process color is obtained. Is converted into an on / off binarized toner signal and output to the image output device 34. The image output device 34 has a scanner 40 and a photosensitive material belt 41, and converts an image signal into an optical signal in a laser output unit 40a.
A latent image corresponding to the document image is formed on the photosensitive material belt 41 via the polygon mirror 40b, the F / θ lens 40c, and the reflection mirror 40d, and the image is transferred to a sheet conveyed from the sheet tray 35 to discharge a color copy. Things.

In the image output device 34, a photosensitive material belt 41 is driven by a driving pulley 41a, and a cleaner 41b, a charger 41c, developing devices 41d of YMCK and a transfer device 41e are arranged around the belt 41. A transfer device 42 is provided to face the transfer device. And paper tray 3
5, the paper fed through the paper transport path 35a is added, and in the case of four-color full-color copying, the transfer device 4
2 is rotated four times to transfer each of the YMCK latent images onto the sheet, and then the sheet is fixed from the transfer device 42 via the vacuum carrying device 43 by the fixing device 45 and discharged. The SSI (single sheet inserter) 35b can selectively supply paper manually to the paper transport path 35a.

The user interface 36 is used by a user to select a desired function and instruct execution conditions. The user interface 36 includes a color display 51 and a hard control panel 52, and further includes an infrared touch board 53 in combination with soft buttons on a screen. You can give instructions directly. The electric system control storage unit 33 includes the image input device 3 described above.
2. a plurality of control boards configured separately for each processing unit such as an image output device 34, a user interface 36, an image processing device, a film projector 64, etc .; further, an image output device 34, an automatic document feeder 62, a sorter An MCB board (machine control board) for controlling the operation of a mechanism such as 63, and a SYS board for controlling the whole thereof are housed therein.

The control device of the copying machine shown in FIG.
Shown in The image input unit 100 has a reduced sensor composed of three line sensors of R, G, and B arranged at right angles in the sub-scanning direction (page sync direction), and is synchronized with a timing signal from the timing generation circuit 12. The image is read by being scanned. The read image data is subjected to shading correction for the balance between pixels due to various factors by the shading correction circuit 11, and then the gap correction circuit 13 performs gap correction between the line sensors. This gap correction is for delaying the image data read by the FIFO 14 by an amount corresponding to the gap so that R, G, and B image signals at the same position can be obtained at the same time.

ENL (Equivalent Neutr)
al Lightness) 15, and the negative / positive inversion signal from the editing processing unit 400 for color conversion, color editing, area generation, pixel density conversion, etc. For example, the negative / positive can be inverted only in a certain designated area.
Further, the matrix circuit 16a converts the R, G, B image signals gray-balanced by the control signal from the editing processing unit 400 into L ', a', b 'image signals in order to facilitate the interface with the outside. . In the selector 17, the output of the matrix circuit 16a or the memory system 2 which is an interface with an external computer is provided.
The image data from 00 is selectively extracted. Selector 1
Reference numeral 7 is connected to a background removal circuit 18 for skipping pixels with a density lower than the background density and improving copy quality, and a document detection circuit 19 for detecting and storing the size of the document.

The matrix circuit 16b converts the L ', a', and b 'image signals, which have been color-edited by the edit processing unit 400, into Y, M, and C toner colors.
Then, the color-edited image data is divided into a plurality of pixels to identify regions of color characters / black characters / patterns (characters / halftones). The under-color removing circuit 21 generates the black board, and outputs the same amount of Y, M, and C in accordance with the monochrome / full-color mode signal and black.
Is performed, the image data of the process color is output, and the hue is determined to generate the hue signal (Hue). The hue signal is temporarily stored in the FIFO 22a, and the image data composed of the halftone image signal of the picture and the character image signal of black characters and color characters is stored in the FIFO 22b.
Is stored once. This hue signal is transmitted to the pictogram separation circuit 20.
The signal is decoded by the area decoder 24 together with the signal based on the result of the pictogram separation from the CPU, and the respective processing units of the filter 25, the multiplier 26 and the TRC 27 operate based on this control signal, and the processing of the image data output from the FIFO 22b is executed. You.

The enlargement / reduction circuit 23a enlarges / reduces the execution area of the area control information for the image even if the reduction / enlargement occurs, and decodes the enlargement / reduction area control information by the area decoder 24 as necessary. Then, it is subjected to processing of each part. The area decoder 24 generates a signal for switching each parameter from the editing command, the area identification, and the hue. The image data reduced or enlarged by the enlargement / reduction circuit 23b is subjected to moire removal and edge enhancement by the filter 25, and the multiplier 26 and the TRC 27 appropriately select a coefficient and a conversion table for each color component. , Color adjustment and density adjustment are performed, and the multiplier 26 calculates the image data to correct the conversion table of the TRC 27. The TRC 27 is for adjusting the density in accordance with the characteristics of the IOT 34. The PAL 29 is capable of switching the conversion table of the TRC 27 by a development process or area identification, and the prepared image data is stored in the memory system or the ROS 300. The dot is developed by the screen generation unit 28, and is output as a halftone image.

Next, in this embodiment, a function will be described in which the above-mentioned color copying machine is used to read a red seal on a bill to recognize that the original is a bill, thereby preventing normal copying. FIG. 1 shows a control block diagram of a bill red seal determining mechanism for that purpose. As described above, the banknote issued by the Bank of Japan has a circular red stamp printed on both the front and back sides. The red stamp on the front side has a diameter of 14.5 mm and the red stamp on the back has a diameter of 13.5 mm regardless of the face value of the banknote. The pattern of the red seal is different on the front side and the back side. It is assumed that the bill red seal has a circular shape shown in FIG.

First, the outline of the procedure up to the determination will be described with reference to a red seal on the surface of a banknote as an example. First, scanning of the original surface with a CCD line sensor (not shown) for reading the original image of the copying machine is started. However, since there is no red printing near the red mark of the bill, the main scanning direction (CC
13. After the reading of the document surface in the scanning direction (D) starts, the detection of the red pixels starts and corresponds to the diameter of the red seal on the bill surface.
If a red pixel equivalent to a 5 mm pitch is detected, it can be assumed that it is based on a red circle with a diameter of 14.5 mm. At this time, the detection of the red pixels corresponding to the 14.5 mm pitch may be performed continuously during this time, or the circle corresponding to the line at the diameter position of the outer circle of the bill red seal and the circle in the circle may be used. Any of the cases where the ON state is discontinuous due to the character may be used.

Then, a predetermined distance pitch (Lm) in the sub-scanning direction from the center position (x ₀ , y ₀ ) of the circle having a diameter of 14.5 mm.
It is checked whether a red pixel can be detected at the intersection with the circle at a position shifted by an amount corresponding to (m pitch). Here, the value of L is an arbitrary value having a radius of less than 7.25 mm of the red seal. If a red pixel is detected at the position corresponding to the intersection of the circles on the Lmm pitch line, it is correct to assume that the detected red pixel signal is circular. Further, a predetermined distance (am) of the center of the dmm pitch line within the circle on the Lmm pitch line
m) Count the number of times N corresponding to ON. This predetermined distance a
mm is set so as to correspond to a print area of a character such as “The Bank of Japan” in the bill red seal (a ≦ d). This dm
The number of pixels (number of ONs) N in the amm pitch on the m pitch line is equivalent to the number of pixels on the d pitch line corresponding to a character such as, for example, "The Bank of Japan" in the banknote red seal stored in the buffer memory in advance. Then, the detected circular red information can be determined to be a red seal of a bill.

In the block diagram of the bill red and white seal judging mechanism shown in FIG.
When the red detection circuit 2 detects the red mark, the 14.5 mm pitch line detection circuit 3 detects red in the main scanning direction 14.5 mm pitch ahead. Further, in order to detect a red pixel on a line separated by L mm in the sub-scanning direction, Lmm in FIG.
The standby time for 2.5 mm in this embodiment is 2.5 mm
It is controlled by the Wait circuit 4. Then, after waiting for 2.5 mm in the sub-scanning direction, dmm in FIG.
(3.6 mm) pitch line detection is performed by a 13.6 mm pitch line detection circuit 5. The number N of ONs at a predetermined distance (amm) at the center of the 13.6 mm pitch line is ON / OF.
The count number N is compared with a corresponding numerical value in a buffer memory (not shown) by a comparison / judgment circuit 7, and the count number N is set to a threshold value th.
If within _one and th ₂ range, the red signal is determined to be a red seal of the bill. The determination result is output by the determination result output circuit 8.

[0023] In addition, the ON number of times and _{N 1,} the other to the ON / O
FF change the number of times _{N 2} is also _{required, N = wN 1 + (1} -w) N 2
The accuracy of the determination is further increased when N is obtained by In the case of a red stamp on the surface of a bank note issued by the Bank of Japan, L = 2.5 mm, w
At 0.1, the count number N is 5 to 25. In the present embodiment, the buffer memory of the bill red seal determining mechanism is the ON / O.
Since only the memory capacity for the thresholds th ₁ and th ₂ of the FF count is required, a low-cost detection device can be provided.

FIG. 3 is a flow chart for the above-described bill red and white seal determination. The red seal determining mechanism of the present embodiment is not operated, for example, when copying a monochrome document or during monochrome copying of a color document image. It is desirable to be able to do so. Therefore, the operation of the banknote red seal determination function may be limited to full-color copying or three-color copying.

When the banknote uses magnetic ink, when the original is set on the platen, the original is detected by a magnetic detector provided in a platen cover, and the banknote is detected. Can be combined. At this time, when the magnetic detection signal of the bill is first received by the magnetic detector, and the bill red seal judging mechanism is operated for the first time, the copying operation that is frequently performed without abuse of the original can be quickly performed. . In addition, the mechanism for judging the red seal of the banknote to be performed after the detection of the magnetism is as follows.
It is possible to judge a banknote with a sufficiently high probability simply by judging a circle having a pitch of 5 mm or simply judging a circle having a pitch of 14.5 mm. It is not necessary to dispose the magnetic detector on the entire surface of the platen cover, and it is sufficient to dispose the magnetic detector at a required position at an interval slightly shorter than the printing width of the magnetic ink.

Further, when the magnetic detector in the platen cover reacts, copying at the same magnification (100%) may not be possible without operating the bill red judging mechanism. In addition, when the magnetic detector responds, the paper quality of the paper is detected by a sensor etc. installed in the paper tray, and if the paper can be misused as a banknote, the operation of the copier is stopped. Can also. Further, at this time, it may be possible to perform processing such as changing the color of only the color area used for the banknote and output it, or to output with a smelled toner. Of course, a plurality of these operations can be combined.

In addition, the gloss of the paper to be copied is increased and output by a method such as combining with the above operation, or the presence or absence of printing on the back surface near the registration roll is checked by a photo sensor or the like at the time of double-sided copying (particularly during manual operation). ) Or the friction (slipping) of the feed roller is detected in the determination of double-sided copying, and if there is a risk of abusive copying, the operation can be shifted to a stop of copying or the like. Further, a histogram of a density or a print pattern unique to a document such as a bill, for example, the number of detection pixels in each density region of a plurality of density regions is stored in a memory, and based on this, the document to be detected is a bill or the like. It is also effective to check whether or not the document should not be abused. At this time, the histogram can be applied to a specific area or an entire area of the document.

Similarly, the density of a document such as a bill or a profile of a print pattern, for example, a density change in a direction orthogonal to each coordinate axis in the longitudinal direction of the document is stored in a memory, and a detection is performed based on this. It is also effective to check the target manuscript. At this time, the profile can be applied to a specific area or an entire area of the document. In addition, a feature may be provided in which a feature point of a specific person image of a bill is stored in a memory, and when read information on the feature point is input, the bill is determined to be a bill. In the case of bills, since the watermark has a characteristic, the characteristic point of this watermark may be processed in the same manner as the above-mentioned person image.

FIG. 4 shows a bill red seal determining mechanism according to the present embodiment.
When provided on the image output means as described above, not only the scanner signal inside the image reading means, but also the scanner signal transmitted from an external device directly transmitted to the image output means, the bill red seal determining mechanism Can be passed through. In addition, when the bill red seal determining mechanism of the present embodiment determines the red seal of a bill, the writing timing of the front and back of the copy paper can be randomly performed using a random number table or the like. This is to make use of the fact that creation of counterfeit banknotes becomes impossible if the writing start timing changes unpredictably on the front and back of the copy sheet.

Further, when the bill red seal determining mechanism of the present embodiment determines the red seal of a bill, the copy paper always becomes a print that cannot be used as a bill, for example, a logo such as "copy" or "impossible". If a configuration is adopted in which the mark is automatically printed at least on the front or back of the copy sheet, it is impossible to abuse a copy of the bill. In addition, such a logo mark is put on the paper immediately after copying or at the time of standby of the copying machine by printing the logo mark of a copying machine maker or the like by a printing mechanism.
If it is specified that the paper is copied from a manuscript, it is possible to prevent abuse copying of bills and the like. By printing a logo mark of a copier maker or the like on all copies, it is useful for copyright protection. In particular, high-performance color copiers have made it easy to obtain copies of the same quality from photo books, etc., so it is meaningful to print the logo on the copies. is there.

In this embodiment, the means for preventing the abuse copying of the document has been described mainly with respect to the bill red seal judging mechanism. However, the present invention is not limited to the bill red and white seal judging mechanism. With the combination, the most suitable one according to the purpose can be selected. Next, a description will be given of a document for preventing image processing which has been specially printed in order to prevent faithful copying of a color document such as banknotes and securities, and an image processing apparatus for preventing abusive image processing of the document.

FIG. 5 shows an example of a concentric code. In the concentric code, at least one of the line thickness of each circle, the interval between the lines, and the diameter of each circle has a certain regularity. If the regularity can be identified on the copying machine side, the abuse of the document can be easily prevented. If the rules applied to optical barcodes, which are currently widely used, are applied to the concentric codes as they are, a document misuse prevention function that can be accepted worldwide can be established. In order to identify the concentric code of the document, the copier may be provided with the following concentric code determination function. Since the circular image of the present embodiment can be read as a circular image regardless of the direction in which the original is set on the original reading surface of the copying machine, attention is paid to the fact that the means for identifying the image can be configured relatively easily. It is. FIGS. 6 and 7 show block diagrams of a control circuit which is a concentric code judging mechanism.

The concentric circle judging mechanism shown in FIG. 6 detects a concentric image detecting circuit 70 for detecting a concentric image on the document surface, and detects a concentric circle detected by the concentric image detecting circuit 70 at a position separated by a predetermined distance from the diameter or the center of the concentric circle. Is stored in the buffer memory 72, and if the pattern matches the string pattern corresponding to the concentric circles previously stored in the buffer memory 72, the detected circular image is determined to be a specific concentric circle. A concentric circle judgment circuit 71 and a judgment result output circuit 73 for outputting the judgment result are provided. The concentric circle determination circuit 71 detects and stores the diameter of the concentric circle or the distance between the intersections with a plurality of concentric circles on the chord at a position separated by a certain distance from the center, and stores the distance in the buffer memory 72 corresponding to the previously stored concentric circle. , The detected circular image can be determined to be a specific concentric circle.

An outline of the procedure for performing the concentric code determination when using the concentric circle determination mechanism shown in FIG. 7 will be described.
First, an image (not necessarily a concentric image) is obtained by reading and scanning the original surface in the main scanning direction (CCD scanning direction).
Is started, the image information to be detected thereafter is stored in the buffer memory 2. When the pixels at the two positions corresponding to the diameters of the concentric circles are detected, the pixels are assumed to have detected the two points at the diameters of the circle, respectively, and the center position is calculated. If circular information is stored in the buffer memory 2 at both ends of the diameter rotated by a predetermined angle from the main scanning direction, the assumption that the detected pixel signal is circular is correct.

Further, since there are concentric circles having different line intervals, line thicknesses, etc. in the circle, the number N of pixels in the circle which is the image stored in the buffer memory 2 is counted, and the number N of pixels is determined in advance. If the calculated number of pixels matches the number of pixels corresponding to the concentric circle, it can be determined that the detected circular image is based on a specific concentric circle. When the concentric circle detection circuit 70 detects an image in the control block diagram of FIG. 7, the image is stored in the buffer memory 72. At the same time, the main scanning direction detection signal thinning circuit 71-1 thins the detection signal in the main scanning direction. This thinning is easily performs signal detection in the next main scanning direction d ₀ mm pitch signal detection circuit 71-2. In the buffer memory 72 in which the circular pixel information is stored, when a pitch signal of ₀ mm in the main scanning direction is detected, a memory necessary for detecting a pitch signal of ₀ mm in the sub-scanning direction and the oblique direction is sufficient. The capacity of the buffer memory 72 may be very small, and the cost of the buffer memory 72 can be reduced.

Concentric circle detection circuit 70 and main scanning direction d ₀ mm
The pitch signal detection circuit 71-2 to the both detection pixels, as a pixel detector 70,71-2 detects the both of which are both ends of the diameter circle, the center of the circle the center x ₀ of the circle The position calculation circuit 71-6 calculates. Circle corresponding to the circumference position of d ₀ mm pitch center x _{0 (Figure} 8) a predetermined angle in the main scanning direction in the reference from, for example, the sub-scanning direction or position is 45 ° oblique direction rotated from the main scanning direction of the circle pixel information d ₀ mm pitch signal detection circuit 71-3 in the oblique direction or the sub scanning direction or shaken or stored in the buffer memory 72 is detected. When the circular pixel information is also detected in the oblique direction d ₀ mm pitch signal detection circuit 71-3, the in-circle pixel number counting circuit 71-4 counts the number of pixels in the circle, and stores the number of concentric pixels stored in advance. Are compared and determined by the comparator 71-5. If the determination of the number of pixels in the comparator 71-5 in the vertical threshold (th ₁ and th _2), the determination result output circuit 7
3 is output as a set concentric circle.

FIG. 9 is a flowchart for the concentric circle judgment of the concentric circle judgment mechanism of FIG. Further, in the bills and the like used in the automatic money changer, since the bill setting position is specified, the thickness of the line of each circle of the concentric code, the line spacing of each circle, the size of the diameter of each circle In addition to or in addition to changing the notch, providing a notch in each circle, further limiting the notch position to a specific location, etc., so that the notch can be detected further, Abuse of the original such as bills can be prevented.

In the above, an example has been described in which a concentric code is printed on a document, and the concentric code is read by an image processing apparatus. However, if the following functions are added to the document in addition to the concentric code,
Prevents misuse of manuscripts. (1) A watermark in the form of a tracing paper is attached. This watermark portion utilizes the fact that copying is impossible. (2) Perform special color printing. An image printed with ink of gold, silver, pale pink, or the like utilizes the fact that the color cannot be faithfully reproduced at the time of copying. (3) Apply gloss to the printing surface. Gloss utilizes the fact that it cannot be copied. (4) Attach magnetic tape or print magnetized iron powder or iron powder, or print transparent or white magnetic ink on paper. If a magnetic detection sensor is provided on the platen cover side of the copying machine, an abuse copy prevention function of the document can be activated when the document is set on the platen. (5) The paper itself can be copied only by the paper specified by the copier maker, or the paper can be copied only by printing a specific logo on the back of the paper.

Copying cannot be performed by, for example, preventing only the specific paper from being conveyed in the copying machine. For example, at the time of copying a monochrome document or at the time of monochrome copying of a color document image, by not operating the function for red seal determination, the intended copy can be quickly performed when the concentric circle determination mechanism is unnecessary. Is desirable. When it is determined that the image is a circular image of the document, a density histogram in a concentric circle stored in advance or a histogram calculated from a density of ON pixels in a circle of the document stored in the buffer memory and a density profile is stored. Alternatively, the concentric code can be determined in association with the density profile.

When the original is set on a platen when magnetic ink is used for the original, the original is detected by a magnetic detector installed in a platen cover. Can be combined. At this time, when the magnetic detection signal of the original is first received by the magnetic detector and the concentric circle determination mechanism of the original is actuated for the first time, the copying operation which is frequently performed without abuse of the original can be quickly performed. .
Further, the concentric circle judging mechanism of the original, which is performed after the detection of the magnetic field, judges the concentric circle with a pitch of d ₀ mm or simply d _0.
It is possible to judge a document with a sufficiently high probability only by judging a circle with a mm pitch. It is not necessary to dispose the magnetic detector on the entire surface of the platen cover, and it is sufficient to dispose the magnetic detector at a required position at an interval slightly shorter than the printing width of the magnetic ink.

Further, when the magnetic detector in the platen cover reacts, the original may not be copied at the same magnification (100%) without operating the concentric circle judging mechanism. In addition, when the magnetic detector responds, it is possible to detect the paper quality of the paper by a sensor or the like installed in the paper tray, and to stop the operation of the copying machine if the paper is for originals. . Further, at this time, it may be possible to perform processing such as changing the color of only the color area used in the document and output the image, or output the image using scented toner. Of course, a plurality of these operations can be combined.

Further, the gloss of the paper to be copied is increased and output by a method such as combining with the above operation, or the presence or absence of printing on the back surface near the registration roll is checked by a photo sensor or the like at the time of double-sided copying (especially during manual operation). ) Or the friction (slipping) of the feed roller is detected in the determination of double-sided copying, and if there is a risk of abusive copying, the operation can be shifted to a stop of copying or the like. Furthermore, the density of the original or the histogram of the print pattern, for example, the number of pixels detected in each of the plurality of density areas is stored in the memory, and based on this, the original to be detected is copied to the abuse of the original. It is also effective to check whether a document should not be printed. At this time, the histogram can be applied to a specific area or an entire area of the document.

Similarly, a density or print pattern profile unique to the document, for example, a density change in a direction orthogonal to each coordinate axis in the longitudinal direction of the document is stored in a memory,
Based on this, it is also effective to check the document to be detected. At this time, the profile can be applied to a specific area or an entire area of the document. In addition, a feature may be provided in which characteristic points of a person on a document on which a specific person image is printed are stored in a memory, and when read information on the characteristic points is input, the document is determined to be a document. . In the case of bills, since the watermark has a characteristic, the characteristic point of this watermark may be processed in the same manner as the above-mentioned person image. Further, when the concentric circle determination mechanism of this embodiment is provided in the image output means IOT as shown in FIG. 10, not only the scanner signal inside the image input means IIT but also the external signal transmitted directly into the image output means IOT. The scanner signal transmitted from the device can also be passed through the document concentricity determination mechanism. IPS is an image processing means, P
C is a personal computer.

When the concentric circle of the original is judged by the concentric circle judging mechanism of the present embodiment, the writing timing of the front and back sides of the copy sheet can be randomly determined using a random number table or the like. This is to make use of the fact that creation of a forged manuscript becomes impossible if the writing start timing on the front and back of the copy paper changes without predictability. Further, if the concentric circle judgment mechanism of the present embodiment judges the concentric circle of the original, the copy paper cannot be used as the original without fail, for example, "copy".
If a configuration is adopted in which a logo mark such as "unusable" is automatically inserted at least on the front or back of a copy sheet, it is impossible to abuse a copy of the document.

It is to be noted that such a logo mark is clearly indicated that the paper has been copied from an original by inserting a logo mark of a copier maker or the like into the paper immediately after copying or during standby of the copier by a printing mechanism. Then, it is possible to prevent the abuse copying of the original and the like. By printing a logo mark of a copier maker or the like on all copies, it is useful for copyright protection. In particular, high-performance color copiers have made it easy to obtain copies of the same quality from photo books, etc., so it is meaningful to print the logo on the copies. is there. Although the present embodiment has described the abuse copy prevention means by the copying apparatus centering on the abuse copy prevention manuscript and the concentric circle judging mechanism, the present invention is not limited to this. By combination, the optimal one according to the purpose can be selected.

Next, a description will be given of an embodiment of an image processing apparatus having a function for preventing image processing of a document which is designed to add specific pattern information to read digital image data and print the digital image data. FIG. 11 shows a copy sheet on which pattern information is printed. On the copy paper processed by the image output means, a pattern information print area is provided so as to overlap a copy image forming area for forming a copy image, and the pattern information built in the apparatus is printed on the pattern information print area. Is done. Here, whether the pattern information print area is set as a copy image formation area to be added to all of the read image data and printed, or a specific area is set in the copy image formation area according to the device specification. You can choose. For example, as a specific area,
The range may be limited to only a specific density range of the digital image data.

To explain the mode of the pattern information, the pattern information uses character information or encoded information, the character information is composed of a combination of numbers and symbols, and the encoded information is composed of significant information by a combination of dots. Is done. In the case of character information, any of meaningless information in which the combined specific numerical value, symbol, or the like has no meaning or significant information in which the meaning itself is given may be used. These pieces of information are constituted by an area or density below the detection limit of the human eye, that is, below the visual limit, or a combination of the area and the density. For example, the area and density of each dot used for the encoded information are set to be equal to or less than the visual limit.

Normally, a color copying machine is printed with four color plates of yellow, magenta, cyan and black together with printing, so that a specific color among them is, for example, a single color or a combination of a plurality of colors. Print pattern information. Preferably, the specific color is yellow which is most difficult to detect by human eyes. Further, when the pattern information enters a white background, it tends to be noticeable depending on the specific color used. Therefore, it is necessary to control the density of the pattern information with high precision. Therefore, by adopting a configuration in which the specific color used in the digital image data is added only to the inconspicuous specific density area, that is, the area other than the white area, the density control of the pattern information becomes easy.

The encoding information is obtained by converting a character string into a code, converting the character string into pattern information represented by a bit string of one row, and adding the pattern information to digital image data. For example, the pattern information shown in FIG. 12 is obtained by converting a character string into an ASCII code, and further converting a 1-byte code into pattern information represented by a bit string in one row. One bit is two pixels in the main scanning direction,
It is expressed by a dot pattern of one pixel in the sub-scanning direction, and its density is set to the highest density that can be reproduced by the image output device. In this example, the encoding information is composed of only alphanumeric characters. Character information for 7 bits of an 8-bit ASCII code is inserted, and the remaining 1 bit (most significant bit MS)
B) is used for error correction information (odd parity check). That is, FFh is set in the first line as a guide for the digit positions in the second and subsequent lines. ASC in lines 2 to N-1
II is a bit string. Data for a parity check in the vertical direction is placed in the Nth row. According to the present embodiment, the dot pattern can be recognized with an extremely small dot area, so that a dot pattern that is less noticeable than character information can be obtained. In addition, since dot identification is less affected by density than character information, density control becomes easier.

Next, an explanation will be given of image processing for preventing a partial abuse of a copy sheet on which pattern information is printed. FIG. 13 shows a copy sheet on which periodic pattern information is printed. A large number of pieces of pattern information are arranged vertically and horizontally on a copy sheet at a predetermined area and at predetermined intervals. With such a configuration, the pattern information to be printed enters the entirety of the copy sheet finely, so even if an attempt is made to use the portion of the copy sheet, the printed pattern information enters there. Therefore, partial abuse of the copy sheet can be prevented. FIG. 14 shows encoded information having periodicity. In this example, encoded information having an area of 320 dots vertically and 160 dots horizontally is provided with periodicity, and the encoded information is arranged in a mesh pattern.

FIG. 15 shows a hardware configuration of an image processing system for adding pattern information. The system configuration for reading a document image by a scanner in pixel units and performing image processing on the read image data and outputting the processed image data is the same as the configuration shown in FIG.
The pattern adding device adds the above-described pattern information to the digital image data processed by the image processing device. Next, an embodiment of the pattern adding apparatus will be described in which encoded pattern information is added. FIG. 16 shows a hardware configuration of an apparatus for adding a pattern of encoded information having periodicity.

The block interval setting section 80 sets a repetition period of the pattern information. The dot interval setting unit 81
The interval between the dots constituting the pattern information is set. The register 82 holds a dot interval set value written by the CPU and ON / OFF of the dot. The counter selector 83 controls dot printing or non-printing based on the interval set by the dot interval setting unit 81 and the dot ON / OFF information of the register 82. Selector 8
Reference numeral 4 selects whether to output video data (Video Data) as it is or to output pattern information.

In this embodiment, the pattern information is added to all of the read digital image data. However, the image data is stored in advance as image data which must not be copied faithfully. It is also possible to configure so that the pattern adding device is operated only when the patterns are collated and matched.

Next, the addition control or addition prohibition control of a specific pattern based on the detected value will be described. FIG. 17 shows a basic configuration of an image processing apparatus having a function of switching the shape and density of a specific pattern according to a detected density value. After the image signal read by the image reading device is processed by the image processing device, the image is written on the photoconductor by the laser light converted by the laser writing device LD. The density-controlled image is transferred based on the detected density information, and the developed image is transferred to a transfer drum and output.
In the present embodiment, in the density control of image processing, switching control of an additional pattern is performed using the detected output density. That is, in order to check the output density of the image, the toner image (batch) formed on the photoconductor is transferred to a transfer drum, and the density of the transferred batch is detected by the image density (ADC) sensor 5.

The additional pan selection device includes an ADC sensor 10
A specific pattern is selected based on the detected density value from 0, and this switching signal is sent to the pattern adding device 4. The pattern adding device determines a pattern from a plurality of specific patterns prepared in advance by a switching signal from the additional pattern selecting device, and sends the pattern signal together with the image signal from the image processing device to the image writing device LD. Add a specific pattern to the processed image. As a plurality of specific patterns prepared in the pattern adding device,
A description will be given using encoded information as an example. FIG. 18 shows a sheet on which an encoded pattern is printed. FIG. 19 is an example of an encoding pattern switched according to the output density of an image. A specific coded pattern is image-processed and printed on paper, and since this coded pattern tends to be printed dark when the output density is high, for example, printed with small dots, When the output density is low, printing is performed with large dots. In the illustrated example, a specific pattern is formed by one dot when the output density is high and by two dots when the output density is low.

By the way, although humans do not notice much,
When adding a pattern that can be read by a scanner and image processing to an image, if the density of the pattern to be added is too high, it is recognized as fog by the human eye, and if it is too low, the pattern cannot be read by the scanner and image processing. There is
According to the present embodiment, since a pattern having an optimum shape and density is added according to the detected output density, abuse image processing of a document can be prevented without deteriorating image quality.

FIG. 20 shows the basic configuration of an image processing apparatus having a pattern addition prohibition function for preventing a specific pattern from being added according to the type of transfer paper. Here, as a transfer paper for which addition of a specific pattern is prohibited, an OHP sheet,
Targets a specific color paper. The pattern addition prohibition judging device judges OHP or a specific color sheet based on a detection signal from the OHP detection sensor 101 and / or the sheet detection sensor 102, and sends the result to the pattern addition device. When OHP or a specific color sheet is detected, the pattern adding device does not add a pattern to the image processed by the image processing device in response to the pattern addition prohibition signal from the pattern addition prohibition judging device. Therefore,
The image is output as it is. When plain paper or a color paper other than the above is detected, pattern addition is not prohibited. Therefore, the pattern adding device adds a pattern to the processed image and outputs the image.

In this embodiment, the OHP detection sensor and the paper detection sensor for detecting a paper of a specific color are provided in combination, but may be constituted by only one of the sensors. In addition, by combining these sensors and the ADC sensor, a configuration having both functions of switching a specific pattern and prohibiting the addition of a pattern according to the type of transfer paper can be provided.
By the way, there is a problem that even an added pattern that is not noticeable by humans can be seen at the time of projection on an OPH sheet, or can be seen by humans on colored paper,
According to the present embodiment, control is performed so as not to add a pattern in the above case, so that such a problem can be solved. Manuscripts that are the subject of the present invention are bills, securities such as stock certificates and bonds, commuter passes, admission tickets for events, and cash vouchers. The image processing apparatus of the present invention can be applied to not only a copying machine but also a facsimile and a printer.

[0059]

As described above, according to the present invention, a memory only needs to have a minimum capacity, and a circular image can be detected at a relatively low cost. In particular, a red mark such as a bill is detected. it can. Therefore, a normal image processing prevention function can be obtained at a relatively low cost, so that a function to prevent abuse of the image processing apparatus, such as copying bills, can be added to a low-cost color image processing apparatus. it can.

[Brief description of the drawings]

FIG. 1 is a block diagram illustrating a bill red seal determining mechanism according to an embodiment of the present invention.

FIG. 2 is a conceptual diagram for detecting a circle.

FIG. 3 is a flowchart of a bill determination process.

FIG. 4 is a diagram illustrating a hardware configuration of an image processing apparatus including a bill red seal determining mechanism.

FIG. 5 is a diagram showing concentric circles according to another embodiment of the present invention.

FIG. 6 is a block diagram of a concentric circle determination mechanism.

FIG. 7 is a block diagram of a concentric circle determination mechanism.

FIG. 8 is a conceptual diagram for detecting concentric circles.

FIG. 9 is a flowchart of a document determination process.

FIG. 10 is a diagram illustrating a hardware configuration of an image processing apparatus including a concentric circle determination mechanism.

FIG. 11 is an explanatory diagram of a copy sheet on which pattern information is printed according to another embodiment of the present invention.

FIG. 12 is an explanatory diagram of a copy sheet on which encoding information is printed as pattern information.

FIG. 13 is an explanatory diagram of a copy sheet on which periodic pattern information is printed.

FIG. 14 is an explanatory diagram of a copy sheet on which encoded information having periodicity is printed.

FIG. 15 is a diagram illustrating a hardware configuration of an image processing apparatus having a pattern information adding function.

FIG. 16 is a diagram illustrating a hardware configuration of a pattern adding apparatus.

FIG. 17 is a diagram illustrating a hardware configuration of an image processing apparatus having an additional pattern selection function.

FIG. 18 is an explanatory diagram of a copy sheet on which an encoding pattern corresponding to an output density is printed.

FIG. 19 is a diagram illustrating a specific example of an encoding pattern according to an output density.

FIG. 20 is a diagram illustrating a hardware configuration of an image processing apparatus having a pattern addition prohibition function.

FIG. 21 is an overall configuration diagram of a color copying machine according to an embodiment of the present invention.

FIG. 22 is a control block diagram of a color copying machine.

[Explanation of symbols]

1 .... pixel density conversion circuit, 2 .... red detection circuit, 3 .... 14.
5mm pitch line detection circuit, 4 ... 2.5mm Wait
Circuit, 5 ... 13.6mm pitch signal detection circuit, 6 ... ON
/ OFF frequency counting circuit, 7: comparison judgment circuit, 8: judgment result output circuit, 70: concentric circle detection circuit, 71: concentric circle judgment circuit, 71-1: main scanning direction detection signal thinning circuit,
71-2 ... main scanning direction _d 0 mm pitch signal detection circuit, 7
1-3 ... oblique direction _d 0 mm pitch signal detection circuit, 71-
4 ... circle pixel count circuit, 71-5 ... comparator, 71
-6: circle center position calculation circuit, 72: buffer memory,
73: determination result output circuit, 80: block interval setting unit,
81: dot interval setting unit, 82: register, 83: counter / selector, 84: selector, 90: additional pattern selecting device, 92: pattern addition prohibition judging device, 100 ...
ADC sensor, 101: OHP detection sensor, 102: paper detection sensor

 ──────────────────────────────────────────────────続 き Continuing on the front page (72) Inventor Sui Wren 2274 Hongo, Fujigo Rocks, Inc., Ebina-shi, Kanagawa Prefecture (72) Inventor Koji Aikawa 2274 Hongo, Hongo, Ebina-shi, Kanagawa Prefecture (72) Inventor Koichiro Shinohara 2274 Hongo, Ebina-shi, Kanagawa Fuji Xerox Co., Ltd. (72) Inventor Fumio Nakaya 2274 Hongo, Ebina-shi, Kanagawa Fuji Xerox Co., Ltd. (56) References JP-A-2-223498 (JP) JP-A-2-210592 (JP, A) JP-A-60-229572 (JP, A) JP-A-4-294682 (JP, A) JP-A-61-285578 (JP, A)

Claims (6)

(57) [Claims] 1. An image processing apparatus for reading a document image in a pixel unit by a scanner, image-processing the read image, and outputting the read image, a specific color detecting means for detecting a specific color of the document image, and the specific color detection A first predetermined distance pitch line image detecting means for detecting specific color images corresponding to both ends of a first predetermined distance corresponding to a diameter of a circle on a line in the main scanning direction with respect to the image detected by the means; When a specific color image is detected by the first predetermined distance pitch line image detecting means, a line separated by a set distance in the sub-scanning direction from a center position of a circle having a diameter equal to the first predetermined distance. A second predetermined distance pitch line image detecting means for detecting an intersection of the line and the circle; and a second predetermined distance pitch line detected by the second predetermined distance pitch line detecting means. A specific color circular image determining means for determining that the outline of the specific color image detected by the series of detecting means is formed from a circular image, and a specific color circular image determining mechanism comprising: Image processing device. 2. An image processing apparatus which reads a document image in a pixel unit by a scanner, processes the read image, and outputs the processed image, wherein a specific color detecting means for detecting a specific color of the document image; A first predetermined distance pitch line image detecting means for detecting specific color images corresponding to both ends of a first predetermined distance corresponding to a diameter of a circle on a line in the main scanning direction with respect to the image detected by the means; When a specific color image is detected by the first predetermined distance pitch line image detecting means, a line separated by a set distance in the sub-scanning direction from a center position of a circle having a diameter equal to the first predetermined distance. Above, a second predetermined distance pitch line image detecting means for detecting an intersection of the line and the circle, and a first line detected by the second predetermined distance pitch line detecting means.
If it is determined that the number of pixels in a predetermined area in the set of lines is within a range of a specific number stored in advance in the storage unit, the outline of the image of the specific color detected by the series of detection units is determined. An image processing apparatus comprising: a specific circular image determining unit of a specific color that is determined to be formed from a specific circular image; 3. A specific color detecting means for detecting a specific color of a document image in an image processing apparatus for reading a document image in a pixel unit by a scanner, and processing and outputting the read image. A first predetermined distance pitch line image detecting means for detecting specific color images corresponding to both ends of a first predetermined distance corresponding to a diameter of a circle on a line in the main scanning direction with respect to the image detected by the means; When a specific color image is detected by the first predetermined distance pitch line image detecting means, a line separated by a set distance in the sub-scanning direction from a center position of a circle having a diameter equal to the first predetermined distance. Above, a second predetermined distance pitch line image detecting means for detecting an intersection of the line and the circle, and a first line detected by the second predetermined distance pitch line detecting means.
When comparing and judging that the number of ON / OFF changes of the pixels in the predetermined area in the set of lines is within the range of the specific number stored in the storage unit in advance, the specific color of the specific color detected by the series of detection units is determined. An image processing apparatus comprising: a specific circular image determining unit of a specific color for determining that an outline of an image is formed from a specific circular image; Wherein said specific color is red, the first predetermined distance d _0, the second predetermined distance d, between the sub-scanning direction set distance L, d = 2√ {(d 0/2 ) ² -L ^2} _{(where, d 0/2>L>} 0) relation holds for the the _{d 0} of the particular circular image substantially 1
The image processing apparatus according to claim 2, wherein the image processing apparatus determines that the paper money is based on a red seal of a banknote of 4.5 mm or 13.5 mm. 5. The image processing apparatus according to claim 2, wherein a specific circular image determining mechanism for a specific color is provided in an image output unit to which an image reading signal from an external scanner is input. 6. The image processing apparatus according to claim 2, further comprising: a specific circular image determining mechanism for a specific color of the image processing apparatus; and a magnetic detector disposed in the platen cover for detecting magnetism on a document side. Characteristic image processing device.