Note : Les descriptions sont présentées dans la langue officielle dans laquelle elles ont été soumises.
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This application is a division of Canadian Patent
Application No. 2,064,353 filed March 27, 1992 for Image
Processing Apparatus and Copying Machine.
BACKGROUND OF THE INVENTION
S Field of the Invention
The present invention relates to an image processing
apparatus having a function for detecting originals of
specific patterns of monochromatic or color images, and
also to a copying machine having such an image processing
apparatus.
Description of the Related Art
Nowadays, copying machines are available which can
produce color copies of extremely high quality, and this
has given a rise to the demand for prevention of forgery of
bills, securities and other valuable papers. To cope with
this demand, it has been proposed to adopt pattern matching
technique in copying machines to detect and reject any
original which should not be copied. In such a technique,
the image pattern of the original input to a copying
2 0 machine, after correction of any inclination, is compared
with image patterns which have been registered in the
machine, for the purpose of recognition and evaluation of
matching of the pattern.
Image processing apparatus incorporated in known
2 5 copying machines of the type described, however, does not
have any means for deciding the state of the image
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recognition function. Therefore, when, for example, the
image recognition function and the image processing
apparatus are formed on different circuit boards, it is
rather easy to demount the circuit board carrying the image
S recognition function, so that the copying machine performs
ordinary copying operation even when the original is a
specific one which should not be copied. This undesirably
allows an easy forgery of the papers such as bills and
securities.
Under this circumstance, the present applicant has
proposed techniques in which each copy is provided with
information which indicates the fact that the copy is a
copy and not an original.
One of such techniques is to combine a specific code
or a pattern with the output image. This technique employs
a function for storing a specific pattern to be added and a
function for combining the pattern with the output image.
In a copy produced by this technique, the specific pattern
is combined with the output image by a color tone or
2 0 density which is not so noticeable to human eyes but is
discriminatable by a specific technique.
In this type of color copying machine, there is no
means for preventing replacement of the parts carrying the
pattern storage and combining functions with a part which
2 5 does not have such functions. After such a replacement,
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the pattern is not added to the output image, so that
forgery can easily be done by using the copying machine.
Furthermore, since the pattern is fixedly stored in
such a manner as not to be changed, it is not possible for
persons such as service men of copying machines to set
different patterns on different machines to enable
identification of the machine from the copy produced by the
machine.
The present applicant also has proposed a method for
preventing illegal copying of bills, securities and so
forth which is a critical problem noticed in recent years
due to high reproducibility of original images offered by
current copying machines. According to this method, data
concerning specific originals such as bills and securities
are beforehand stored in terms of color space. Any
original set on the copying machine is rejected when this
original exhibits the same distribution of data in the
color space as that of one of the above-mentioned specific
originals. However, known copying machines realizing such
2 0 forgery prevention method do not have functions for storing
data concerning illegal use of the machine, e.g., type of
the original illegally copied, type of the input device and
identification of the operator who made such illegal use of
the machine, nor a function for informing an administrator
2 5 of the fact that the copying machine has been used
illegally for the purpose of copying bills or the like.
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Consequently, there is no means for keeping control
over the copying machine against illegal copying,
particularly when the copying machine is set at a place
where there is no person other than the illegal user.
S As explained before, various methods have been
proposed for the purpose of enabling recognition of
specific originals of the kind described.
In all the proposed methods, however, the image
recognition is performed an independent circuit.
Therefore, it is not impossible for those who are familiar
with this type of machine to modify the machine so as to
enable illegal copying of bills or the like, by demounting
the circuit board carrying the image recognition function.
Full-color copying machines also have been proposed in
1S which identification information such as the serial No.-of
the machine is added to the copy produced by the machine.
Such information is given in the form of a mark of light
yellow color or specific binary pattern.
All these known copying machines, however, are still
2 0 unsatisfactory in that they permit easy demounting of the
image recognition or detection function, due to the fact
that such a function is performed by a single circuit board
which is not difficult to demount.
2 S SUMMARY OF THE INVENION
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Accordingly, a primary object of the present invention
is to provide an image processing apparatus, as well as a
copying machine, which can overcome the above-described
problems of the known arts.
Another object of the present invention is to provide
an image processing apparatus, as well as a copying
apparatus, wherein the apparatus itself can examine the
state of the function for recognizing specific original
patterns, thereby to prevent illegal copying of such
specific originals.
Still another object of the present invention is to
provide an image processing apparatus, as well as a copying
machine, which enables free setting of pattern data to be
combined with the output copy image, thus enabling
identification of the copying machine by which any illegal
copying was conducted.
A further object of the present invention is to
provide an image processing apparatus, as well as a copying
machine, which prohibits copying operation when a pattern
2 0 data set in the apparatus has been lost, thereby to prevent
dismissal of anti-forgery function caused by absence of
such pattern data.
A still further object of the present invention is to
provide an image processing apparatus, as well as a copying
2 5 machine, which enables a check by a service man or an
administrator for any dismissal or invalidation of anti-
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forgery function, thus ensuring administration of the
machine against illegal use such as forgery.
A still further object of the present invention is to
provide an image processing apparatus, as well as a copying
machine, which is constructed so as not to allow removal of
forgery detecting function.
A still further object of the present invention is to
provide an image processing apparatus, as well as a copying
machine, which is constructed to make it difficult to
1~ remove a circuit for adding machine identification
information.
A still further object of the present invention is to
provide an image processing apparatus, comprising:
processing means for processing input image signals;
1$ connecting means for connecting a preventing means for
preventing someone from copying a predetermined original;
detecting means for detecting a state of connection between
said connecting means and said preventing means; and
control means for controlling the apparatus in accordance
2 0 with the result of the detection made by said detecting
means.
A still further object of the present invention is to
provide an image processing apparatus, comprising:
processing means for processing input image signals;
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connecting means for connecting a deciding means for
deciding similarity between an image represented by said
input image signals and an image of a specific original;
detecting means for detecting a state of connection between
S said connecting means and said deciding means; and control
means for controlling the apparatus in accordance with the
result of the detection made by said detecting means.
A still further object of the present invention is to
provide a printing apparatus having image processing means
1.0 for effecting a predetermined image processing on an input
image data, comprising: connecting means for connecting a
pattern data generating means for generating pattern data
for identifying the copying apparatus; synthesizing means
for synthesizing said pattern data with said input image
15 data; image forming means for forming an image on a
recording medium in accordance with the synthesized image
data; and control means for prohibiting formation of the
image by said image forming means when said pattern data
generating means is not connected with said connecting
2 0 means .
A still further object of the present invention is to
provide an image processing apparatus, comprising: input
means for inputting image signals; deciding means for
deciding whether an image represented by the image signal
2 5 input through said input means contains an image
corresponding to a predetermined specific original; memory
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means for storing the result of the decision made by said
deciding means; and transmitting means for transmitting the
result stored in said memory means to an external device.
A still further object of the present invention is to
provide an image processing apparatus, comprising: deciding
means for deciding whether an image represented by input
image signals contain an image corresponding to a
predetermined specific original; memory means for storing a
plurality of sectioned decision results obtained as a '
result of the decision; and transmitting means for
transmitting the results stored in said memory means.
A still further object of the present invention is to
provide an image processing apparatus, comprising: input
means for inputting image signals; deciding means for
deciding whether an image represented by the image signals
input through said input means contain an image
corresponding to a specific original; and memory means for
storing the results of the decision made by said deciding
means together with other types of information.
2 0 A still further object of the present invention is to
provide an image processing apparatus, comprising: image
signal processing means for processing image signals for
the purpose of image reproduction; deciding means for
deciding degree of similarity between an image represented
2 5 by said image signals and an image of a specific original;
and altering means for altering the content of the
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processing performed by said image signal processing means,
in accordance with a degree of similarity decided by said
deciding means; wherein at least a part of said image
signal processing means and at least a part of said image
$ deciding means are formed as one unit with each other.
A still further object of the present invention is to
provide a printing apparatus, comprising: deciding means
for deciding whether a specific original is being copied;
and processing means for performing a printing process;
wherein at least a part of said deciding means and at least
a part of said processing means are constructed as one unit
with each other.
A still further object of the present invention is to
provide an image processing apparatus, comprising: image
processing means for obtaining density signals from input
image signals; and adding means for adding a predetermined
pattern to an image represented by said density signals
obtained by said image processing mans; wherein at least a
part of said image processing means and said adding means
2 0 are formed on a common printed board.
A still further object of the present invention is to
provide a printing apparatus, comprising: image processing
means for obtaining density signals from input image
signals; and adding means for adding a predetermined
2 5 pattern to an image represented by said density signals
obtained by said image processing mans; wherein at least a
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part of said image processing means and, said adding means
are formed on a common printed board.
A still further object of the present invention is to
provide an image processing apparatus, comprising: image
processing means for obtaining density signals from input
image signals; binarizing means for binary-coding the
density signals obtained by said image processing means;
and adding means for adding a predetermined pattern to an
image represented by the binary-coded signals; wherein said
binarizing means and said adding means are formed on a
common circuit board.
A still further object of the present invention is to
provide a printing apparatus, comprising: image processing
means for obtaining density signals from input image
signals; binarizing means for binary-coding the density
signals obtained by said image processing means; and adding
means for adding a predetermined pattern to an image
represented by the binary-coded signals; wherein said
binarizing means and said adding means are formed on a
2 ~ common circuit board.
A still further object of the present invention is to
provide a semiconductor chip, comprising: input terminal
for inputting image data; decision circuit for deciding
whether the image data represents a predetermined image;
2 S processing circuit for processing the image data for a
reproduction; and output terminal for outputting the
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diciding result of said decision circuit and the processed
image data.
A still further object of the present invention is to
provide a semiconductor chip, comprising: input terminal
for inputting image data; generating circuit for generating
a pattern data representing a predetermined pattern for
identifying an apparatus for which the semiconductor chip
is applied; processing means for synthesizing the pattern
data with the input image data; and output terminal for
outputting the synthesized image data.
These and other objects, features and advantages of
the present invention will become clear from the following
description of preferred embodiments, as well as from the
statement of claims, when the same are read in conjunction
with the accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
Fig. 1 is a block diagram of a decision circuit 409
2 0 used in a first embodiment of the present invention;
Fig. 2 is a sectional side elevational view of the
embodiment of a copying apparatus in accordance with the
present invention;
Fig. 3 is a block diagram of an image scanner unit 201
2 5 used in the first embodiment;
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Fig. 4 is a block diagram of the decision circuit 409
used in the first embodiment;
Fig. 5 is a circuit diagram of a thinning circuit used
in the first embodiment;
Fig. 6 is a circuit diagram of a frequency-dividing
circuit used in the first embodiment;
Fig. 7 is a block diagram of an integrator 306 used in
the first embodiment;
Fig. 8 is a timing chart showing timings of signals in
a main scanning performed in the first embodiment;
Fig. 9 is an illustration of signals input to and
output from the integrator 306;
Fig. 10 is an illustration of another forms of signals
input to and output from the integrator 306;
Fig. 11 is an illustration of the result of processing
performed in the first embodiment;
Fig. 12 is a flow chart illustrating principal image
processing operations performed by the first embodiment;
Fig. 13 is a block diagram of a second embodiment of
2 0 the copying machine in accordance with the present
invention;
Fig. 14 is a block diagram of a digital color copying
machine as a third embodiment of the present invention;
Fig. 15 is a sectional side elevational view of the
2 S digital color copying machine shown in Fig. 14;
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Fig. 16 is an illustration of a display which is
produced when the copying machine of the third embodiment
is used in add-on mode;
Fig. 17 is an illustration of a display of a code
train which is set when the copying apparatus of the third
embodiment is used in "secret" mode;
Fig. 18 is an illustration of an example of a warning
display which is produced when an add-on board is not
connected correctly;
Fig. 19 is a flow chart illustrative of the copying
process performed by the copying machine of the third
embodiment;
Fig. 20 is a block diagram of a first modification of
the third embodiment, having a different form of connection
of a font ROM;
Fig. 21 is a block diagram of a second modification of
the third embodiment, having a dip switch for enabling
setting of the "secret code";
Fig. 22 is an illustration of a display which is
2 0 presented when the modification shown in Fig. 21 is used in
the add-on mode;
Fig. 23 is an illustration of a remote monitoring
system used for a digital color copying machine which is a
fourth embodiment of the present invention;
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Fig. 24 is a block diagram of an image processing
system incorporating an image processing apparatus as a
fifth embodiment of the present invention;
Fig. 25 is a block diagram of a modem board used in
S the fifth embodiment;
Fig. 26 is a block diagram of the image processing
apparatus of the fifth embodiment;
Fig. 27 is a block diagram of a normalizing circuit
used in the fifth embodiment;
Fig. 28 is a block diagram of a decision circuit used
in the fifth embodiment;
Fig. 29 is a block diagram of a color space decision
circuit used in the fifth embodiment;
Fig. 30 is an illustration of the content of a
programmable ROM used in the fifth embodiment;
Fig. 31 is an illustration of operation of a smoothing
circuit used in the fifth embodiment;
Fig. 32 is an illustration of the relationship between
an input Xn and an output value Yn obtained through the
2 0 smoothing operation used in the fifth embodiment;
Fig. 33 is an illustration of the construction of a
decision signal generating circuit used in the fifth
embodiment;
Fig. 34 is a flow chart illustrating the operation of
2 5 a CPU incorporated in the fifth embodiment;
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Fig. 35 is a circuit diagram of a counter circuit used
in the fifth embodiment;
Fig. 36 is a top plan view of the manipulating portion
of the fifth embodiment;
S Figs. 37 and 38 are illustrations of copy prohibition
messages produced in the fifth embodiment;
Fig. 39 is a block diagram of the copying machine
using the fifth embodiment;
Fig. 40 is a circuit diagram of a counter portion of a
sixth embodiment of the present invention;
Fig. 41 is an illustration of the relationship between
select signal and the input image processing device in the
sixth embodiment;
Fig. 42 is a block diagram of an image scanner portion
of the seventh embodiment;
Fig. 43 is a block diagram of an essential portion of
the image scanner portion shown in Fig. 42;
Fig. 44 is a circuit diagram of a decision circuit
used in a seventh embodiment;
2 0 Fig. 45 is a block diagram of an image scanner in the
eighth embodiment;
Fig. 46 is a block diagram of an essential portion of
the image scanner shown in Fig. 47;
Fig. 47 is a timing chart showing timings of signals
2 $ HSYNC and VCNT in the eighth embodiment;
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Fig. 48 is a block diagram of a 2-bit counter used in
the eighth embodiment;
Fig. 49 is a block diagram of a decision circuit used
in the eighth embodiment;
S Fig. 50 is a timing chart showing timings of signals
HSTNC and VCNT2 in a ninth embodiment of the present
invention;
Fig. 51 is a block diagram of a 2-bit counter used in
the ninth embodiment;
Fig. 52 is a block diagram of an image scanner of the
ninth embodiment;
Fig. 53 is a block diagram of a critical portion of
the image scanner shown in Fig. 52;
Fig. 54 is a block diagram of an image scanner used in
a tenth embodiment of the present invention;
Fig. 55 is a block diagram of a critical portion of
the image scanner shown in Fig. 54;
Fig. 56 is a timing chart showing timing of switching
over of a CNO signal in the tenth embodiment;
2 0 Fig. 57 is a block diagram of a pattern adding circuit
used in the tenth embodiment;
Fig. 58 is an illustration of the result of copying
operation performed by the tenth embodiment;
Fig. 59 is a block diagram of an image scanner used in
2 5 an eleventh embodiment of the present invention;
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Fig. 60 is a block diagram of a critical portion of
the image scanner shown in Fig. 59;
Fig. 61 is a block diagram showing the circuit
arrangement of an image processing section of a full-color
copying machine which is a twelfth embodiment of the
present invention;
Fig. 62 is a block diagram of an essential portion of
the image processing section shown in Fig. 61;
Fig. 63 is a block diagram of a dot pattern detection
and correction circuit used in the twelfth embodiment;
Fig. 64A-64D are illustrations of an example of a
binary pattern used for coding operation performed in the
twelfth embodiment;
Fig. 65 is a block diagram of an added pattern
generation circuit used in the twelfth embodiment; and
Fig. 66 is an illustration of the relationship between
a CNO signal and printing output.
BRRIEF DESCRIPTION OF THE EMBODIMENTS
Preferred embodiments of the present invention will be
described in detail with reference to the accompanying
drawings. Although copying machines are specifically
mentioned in the following description, it is to be
2 5 understood that the invention can be applied to a variety
of types of apparatus. The embodiments described
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hereinunder are intended for preventing copying of specific
originals such as bills, securities and so forth, for the
purpose of prohibiting forgery.
(First Embodiment)
A description will now be given of the whole
construction of a copying machine.
Fig. 2 is a sectional side elevational view of a
copying machine as a first embodiment of the present
invention. The copying machine has an image scanner 201
which reads an original and converts the read image into
digital signals. Numeral 20-2 designates a printer which
produces a full-color print of an image corresponding to
the image of the original read by the image scanner 201.
The image scanner 201 has a pressing plate 200 with a
mirror surface. An original 204 on an original table glass
203 (referred to as "platen" hereinunder) is illuminated by
a lamp 205. The light reflected by the original 205 is led
to mirrors 206, 207 and is focused on a line sensor 210
(referred to as "CCD", hereinafter) through a lens 209.
2 0 The full-color information components red (R), green (G)
and blue (B) of the image formed on the CCD are delivered
to a signal processing section 211. The lamp 205 and the
mirror 206 mechanically move at a velocity V in the
directions perpendicular to the direction of an electric
2 5 scan of the line sensor. Similarly, the mirrors 207, 208
more at a velocity V/2 in the directions perpendicular to
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the direction of an electric scan of the line sensor.
Consequently, the entire area of the original is scanned.
The signal processing section 211 electrically processes
the image signals of the read original image, so as to
S decompose the image signals into components of magenta (M),
cyan (C), yellow (Y) and black (Bk) and delivers these
components to the printer 202. One of the components M,
C, Y and Bk is delivered to the printer 202 per each scan
performed by the image scanner 201. Thus, one printing
cycle requires four cycles of scanning of the original.
The components M, C, Y and black Bk, supplied from the
image scanner 201, are delivered to a laser driver 212.
The laser driver 212 drives a semiconductor 213 while
modulating it in accordance with the image signal. The
laser beam is deflected by a polygonal mirror 21 and
applied to the surface of a photosensitive drum 217 through
an f- lens and a mirror 216, thereby scanning the surface
of the photosensitive drum 217.
A rotary developing device 218 has a magenta
2 0 developing unit 219, a cyan developing unit 220, an yellow
developing unit 221 and a black developing unit 222. Four
developing units are alternately and successively brought
into contact with the photosensitive drum 217 so as to-
develop, by respective color toners, an electrostatic
2 5 latent image formed on the surface of the photosensitive
drum 217. Numeral 223 denotes a transfer drum for winding
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thereon a paper fed from a paper cassette 224 or 225 so
that the image developed on the photosensitive drum is
transferred to the paper.
Image components of four colors M, C, Y and Bk are
successively transferred to the paper. The paper is then
made to pass through a fixing unit 226 so that the
transferred full-color image is fixed. The paper is then
ejected.
<Image Scanner>
Fig. 3 is a block diagram showing the construction of
the image scanner 201 used in the first embodiment.
Referring to this Figure, the image scanner 201 has CCDs
(solid state imaging devices) 210-1, 210-2 and 210-3 having
red (R), green (G) and blue (B) spectro-sensitivity
characteristics, respectively. Each of the CCDs produces a
signal quantized into 8 bits which represent 256 vales from
0 to 255. The CCDs 210-1, 2102 and 21-3 are disposed at
predetermined distances, so that delay elements 401 and 402
are used for the purpose of correcting spatial offset.
2 0 Log converters 403, 404 and 405 each is composed of a
look-up table ROM or RAM, which converts an illuminance
signal into a density signal. Numeral 406 denotes a
masking and UCR (undercolor removal) circuit. Detailed
description of this circuit is omitted since this circuit
2 5 is well known in this field. This circuit, upon receipt of
three primary color signals, this circuit 406 produces Y,
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M, C and Bk signals in the form of bit trains of a
predetermined length, e.g., 8 bits, thereby forming an
output.
Numeral 407 designates a space filter which also is
known. This filter performs correction of space frequency
of the output signals. Numeral 408 designates a density
conversion circuit 408 which is used for correcting density
characteristics of the printer 202. As is the case of the
Log convert ers 403 to 405, the density conversion circuit
408 is composed of a look-up table ROM or RAM. Numeral 409
designates a decision circuit for deciding whether an
original placed on the copying machine is one of the
aforesaid specific originals. This circuit 409 delivers
the result of the decision in the form of a decision signal
H of 0 or 1 level. Namely, when the input image is
determined as being the image of one of the specific
originals, the decision circuit 409 produces a signal H =
1, otherwise H = 0.
An OR gate circuit 410 produces an OR of each 8-bit
2 0 output V of the density conversion circuit 408 and the
decision signal H which is the output of the decision
circuit 409, thereby outputting a signal V'. When the
output of the decision circuit 409 is H = 1, i.e., when the
original which is being read is determined as being one of
2 S the specific originals, the output of the OR gate 410 is V'
- FF (H: hexadecimal), regardless of the value of the input
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signal V. Conversely, when the decision signal is H = 0,
i. e., when the original which is being read is determined
an original which is difference from the specific
originals, the input signal V is passed and output as an
output V' from the OR circuit 410.
<Timing Chart>
Fig. 5 illustrates a thinning circuit used in the
first embodiment, while Fig. 6 is a circuit diagram of a
frequency dividing circuit used in the same. Fig. 8 is a
timing signal of signals appearing in the direction of the
main scan in the first embodiment. Te timing at which each
main scan is commenced is determined by a man scan
synchronizing signal HSYNC. CLK shows transfer clock
signals in accordance with which the image signals are
1$ transferred. The clock signals CLK also are used as the
basic clocks in various image processing operations
performed in this embodiment. CLK' represents a signal
which is obtained by 1/4 demultiplication of the clock
signal CLK and which is used for giving a time reference to
2 0 the deciding operation performed by the decision circuit
409. A signal SEL is a timing signal used in the above-
mentioned thinning circuit 301. These signals are
generated by circuits shown in Fig. 6. The circuit
comprises an inverter 451, a 2-bit counter 452, an inverter
2 S 453 and an AND gate 454. The 2-bit counter 452, after
being cleared (initialized) by the main scanning
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synchronizing signal HSYNC, counts the clock signals CLK
and delivers the counted value in the form of a 2-bit
signal (D0, D1). The significant bit D1 is output as the
clock signal CLK'. The AND of the signal obtained by
S inverting the less significant bit DO and the significant
bit D1 is delivered as the SEL signal.
The thinning circuit shown in Fig.5, is constructed
by flip-flops 455, 456, 457, 461, 462, 463 which hold data
in accordance with the clock signal CLK, selectors 45$,
1~ 459, 460, and flip-flops 464,465,466 which hold data in
accordance with the clock signals CLK'. Consequently,
signal R' (or G' or B') is thinned out at a rate 1/4 from
the signal R (or G or B) transferred in accordance with the
clock signals CLK. The timing of the signal thus thinned
15 out is synchronous with the clock signal CLK'.
<Decision circuit>
Fig. 4 is a block diagram of the decision circuit 409
used in the first embodiment. In this Figure, numeral 301
designates a thinning circuit which has a construction as
2 0 shown in Fig. 5. The thinning circuit 301 performs
thinning of the data in order to reduce burden on the
decision circuit. Numeral 302 designates a color taste
matching look-up table (referred to as "color taste
matching LUT") which performs color taste matching
2 5 operation by comparing the image which is being read with a
plurality of original images, i.e., the aforementioned
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specific originals. Numeral 303-1, 303-2...... and 303-8
denote color-taste decision circuits which have the same
hardwares. Each of the color taste decision circuit is
composed of an integrator 306, a register 307 and a
comparator 308, as shown in Fig. 6. Each color taste
decision circuit determines whether the original which is
being read contains specific color taste equal to the color
taste of one of the specific originals. Different
registers 307 for the color-taste decision circuits 303-1
to 303-8 hold different contents. Numeral 309 denotes an
OR circuit which, when existence of the image of one of the
specific originals is sensed by at least one of the color
taste decision circuit 303-1 to 303-8, produces an output
"0" and otherwise "1".Although in the described embodiment
a 1-bit signal is used for the evaluation of the degree of
similarity, this is only illustrative and the arrangement
may be such that the degree of similarity is expressed by
a multi-value deciding signal. To this end, a plurality of
registers 307 i used for each color taste decision circuit,
2 0 so as to set a plurality of slice levels.
<Integrator>
Fig. 7 is a block diagram of an integrator 360 used in
the first embodiment. Numerals 501 and 505 denote flip-
flops which hold the data at the moment of rise of the
2 S signal CLK'. A multiplier 502 receives a pair of 8-bit
input signals (A, B) and produces, as a result of the
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multiplication, an 8-bit signal (A x B/255). Numeral 503
also represents a multiplier which receives 1-bit input
signal (A) and an 8-bit input signal so as to deliver an 8-
bit output signal (A x B) as a result of the
S multiplication. As adder 504 receives a pair of 8-bit
signals (A, B) and produces an 8-bit signal (A + B) as a
result of the addition.
Consequently, this integrator produces an 8-bit output
signal yi which is given by the following equation, in
response to a binary input signal xi:
Yi = (x/255) ~yi_1 + (3-xi_1 ..... . . . ... (1)
Symbols a and (3 represent constants of values which
are determined beforehand. Characteristics of the
integrator 306 is determined by the values of these
constants.
Figs. 9 and 10 illustrate input to and output from the
integrator 306 used in the first embodiment.
2 0 The integrator 308 produces an output yi shown in
Fig. 10 in response to an input xi_1 shown in Fig. 9, when
the constants a and (3 are respectively 247 and 8.
Inputs at point 701, 702 are "1" while substantially
all the inputs therearound are "1". Conversely,~the input
2 5 at the point 703 is "0" despite the inputs at all other
points therearound are "1". In such cases, the inputs at
CA 02279589 1999-08-23
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the points 701, 702 and 703 are considered as being noises.
These noises are processed by the integrator 306. Namely,
a threshold value as at 704 is set in the register 307 so
as to binarizing the output yi of the integrator 306,
S thereby removing noises.
<processing Result>
Fig. 11 illustrates an example of the processing
result. Referring to Fig. 9, numeral 801 designates an
original. It is assumed here that a specific image 803 to
be detected and determined by the copying machine of the
invention exists in a portion of the image of the original
801. When this original is copied, an output result 802
is obtained in which the portion corresponding to the
specific image 803 has been painted in black as denoted by
804 which indicates invalid portion. This means that the
portion of the original image corresponding to the specific
image is not copied to provide any recognizable image
pattern.
Thus, in this embodiment, presence of any original
2 0 image conforming with one of specific originals is detected
by by the decision circuit, and copying of such original
image is prohibited, thereby preventing any forgery of
bills or the like.
A description will now be given of the decision
2 5 circuit 409.
CA 02279589 1999-08-23
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Fig. 1 is a block diagram showing the connections of
components of the decision circuit 409 used in the first
embodiment, while Fig. 12 is a flow chart illustrating
principal image processing operations performed in the
first embodiment.
Referring to Fig. 1, numeral 101 designates an image
decision circuit board for deciding degree of similarity of
an original to a specific original, while 102 designates a
scanner control circuit board. The image decision circuit
board 101 carries a circuit for conducting decision of the
image. In this embodiment, this circuit board 101 carries
no circuit or component other than the image decision
circuit. The scanner control circuit board 102 carries
image processing portion of Fig. 3 which has been explained
before. CCDs 210-1 to 210-3 have been omitted from this
circuit board 102. The scanner control circuit board 201
also carries a CPU 103 and peripheral circuits for
conducting controls of the scanner 201. The image decision
circuit board 101 and the scanner control circuit board 102
2 0 are connected to each other through a connector which is
not shown.
The arrangement is such that, when the image deciding
substrate 101 has been correctly connected to the scanner
control circuit boar 102, a connection recognition signal
2 5 108 is set to "0", whereas, when the image decision circuit
CA 02279589 1999-08-23
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board 101 is connected to the scanner control circuit board
102, the connection recognition signal 108 is set to "1".
The operation of the first embodiment will be
described briefly.
S In response to pressing of a copy start key, the CPU
103 on the scanner control circuit board 102 reads the
state of the connection recognition signal 108 connected to
the input portion of the I/O port 106 (Step S1), thereby
confirming the presence of the image decision circuit board
101 (Step S2). When the level of the connection
recognition signal 108 is "1", i.e., when the image
decision circuit board 101 is not connected, the CPU 103
sets the output port of the I/O port to "0" (Step 3). As a
consequence, the image signal V' is gated by the AND gate
107 so that the output of the gate circuit is 0 in all
cases. In this case, the CPU 103 simultaneously operates
to display, in a manipulating portion (not shown) of the
image scanner 201, an error message indicating that "copy
is prohibited" and controls the copying machine so as to
2 0 prohibit the copying operation (Step S4). The display of
the above-mentioned error message on the manipulating
portion may be conducted by lighting up or flickering of a
lamp or indication by letters formed by a liquid crystal
display. Message also may be given by a voice message.
2 5 The checking of the state of connection of the image
decision circuit board 101 is executed in response to each
CA 02279589 1999-08-23
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pressing of the copy start key. Obviously, the copying
machine performs ordinary copying operation while checking
for presence of an original image conforming with a
specific original, when the image decision circuit board
101 is correctly connected.
Thus, the copying machine of the first embodiment
prohibits copying operation when the image decision circuit
board 101 has been removed or disconnected. It is
therefore possible to prevent forgery, i.e., copying of
bills and securities, even when the function for
recognizing any specific original has been dismissed.
(Second Embodiment)
The first embodiment described hereinbefore is a
copying machine which is composed mainly of an image
scanner and a printer. This, however, is only illustrative
and the invention may be applied to various other types of
devices such as those having communication function, e.g.,
a facsimile.
Fig. 13 shows a second embodiment of the invention
2 0 which also is a copying machine. Numeral 1101 denotes an
image scanner having a construction and functions similar
to those of the image scanner 201 shown in Fig. 2. Numeral
1'102 designates a printer which also has a construction and
functions similar to those of the printer 202 shown in Fig.
2 S 2. Numeral 1105 designates a decision circuit having a
construction and functions similar to those of the decision
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circuit 409 shown in Fig. 3. Numerals 1103 and 1104 denote
OR gates having a construction and functions similar to
those of the OR circuit 410 used in the first embodiment.
Numeral 1107 designates a connection recognition signal
which has the same significance as the connection
recognition signal 109 shown in Fig. 1. Numeral 1106
designates a BUS selector which interconnects the image
scanner 1101, printer 1102 and a communication line. The
BUS selector selects one of the following three connection
1 0 mode s
(1) Image scanner - printer (copying mode)
(2) Image scanner-communication line (facsimile
transmission mode)
(3) Communication line - printer (facsimile receiving mode)
When the circuit board of the decision circuit 1105
has been removed, operation is prohibited in all the three
modes, i.e., copying, facsimile transmission and facsimile
2 0 receiving modes, by processing the output image of the
image scanner 1101 and the input image of the printer 1102
by means of the AND gates 1108 and 1109, in accordance with
the result of checking of the state of the connection
recognition signal 1107.
2 S According to the invention, it is thus possible to
control, not only the copying output but also the outputs
CA 02279589 1999-08-23
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to and from the communication line, by evaluating the state
of the connection recognition signal 1107 which indicates
whether the image decision circuit board is connected
correctly. Therefore, when a user has willfully
disconnected the image decision circuit board, the
outputting of specific images corresponding to specific
originals such as bills or securities is avoided, thus
preventing forgery.
The circuit board carrying the circuit for deciding
presence of a specific original may be composed of a
plurality of separate boards. In such a case, the copying
machines is so constructed that the image processing
operation is prohibited when at least one of such boards
has been removed,
Although a laser beam printer is used in the described
embodiments, it will be clear that the printer other than
the laser beam printer, e.g., an ink jet printer or a
thermal transfer printer, may be used as the printer in the
described embodiments of the invention.
2 0 It is also to be understood that the described method
for evaluating he degree of similarity is not exclusive.
The decision may be conducted by a method other than the
described method, e.g., by a pattern matching.
(Third Embodiment)
2 5 Fig. 14 is a block diagram of a digital color copying
machine as a third embodiment of the present invention,
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while Fig. 15 is a sectional side elevational view of the
digital color copying machine. As will be seen from Fig.1
15, the digital copying machine is mainly composed of a
reader 2201 and a printer 2203.
<Construction of Reader>
Referring to Fig. 14, an image sensor 2100 is composed
of, for example, CCD or the like which converts the read
image information into R, G and B electric signals and
delivers them in the form of analog image signals to an A/D
converter 2101. The A/D converter 2101 converts the analog
image signal into digital image signals and delivers the
digital signals to a color masking circuit 2102.
An undercolor removing circuit 2103 removes grey
components from the tri-color signal and substitutes the
same with a black signal. A gradation correction circuit
2104 conducts various gradation processings including gamma
correction, brightness correction, contrast correction and
density conversion. An image modulator 2105 incorporates a
region generating circuit (not shown). Various image
2 0 processing operations are performed on the basis of the
regions generated by this circuit. Enlargement and
contraction are performed by a magnifying/de-magnifying
circuit 2107.
An add-on board 2116 is connected to the body of the
2 5 copying machine through a connector 2117. More
specifically, the connector 2117 interconnects an image
CA 02279589 1999-08-23
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data BUS 2121, a signal line 2119 and the CPU BUS 2118.
The signal line 2119 is always kept in active state by mans
of an add-on character generator circuit 2109, and is set
to positive state when the add-on board 2161 has been
demounted from the copying machine. The add-on character
generating circuit 2109 generates image signals on the
basis of patterns stored in a font ROM 2110. This pattern
is used as a code which indicates that the output image is
a copy image but not the original image.
An image synthesizing circuit 2106 forms a synthesizes
an image from the image signal derived from the original
and the image signals from the add-on character generator
circuit 2109. This synthesis is conducted in such a
manner that, for example, the image from the add-on
character generator 2109 is output at a predetermined
density and a color tone. An effective anti-forgery
function is obtained by outputting the image from the add-
on character generator 2109 with a color tone and density,
e.g., light yellow, which are not so noticeable to human
2 0 eyes but are detectable without fail by a device such as a
CCD. An interface (I/F) 2108 provides an interface
between the reader 2201 and the printer 2203 (see Fig. 15)
which functions as the image forming section. The
interface 2108 provides communication between the reader
2 S 2202 and the printer 2203 for various serial signals, as
well as image signals. A CPU 2112 connected to the system
CA 02279589 1999-08-23
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BUS 2111 controls the whole copying machine in accordance
with control programs stored in the ROM 2114, while using a
RAM 2113 as the work area. An operating portion 2115 is
constructed so as to enable setting of copying conditions,
S i.e., combination of copying factors such as density,
number of copies to be produced, magnification and so
forth, for the image which is read by the image sensor
2100.
<Construction of Printer>
Referring to Fig. 15, a polygonal mirror scanner 2301
deflects a laser beam to scan the surface of a
photosensitive drum 2318 with the laser beam. An image
forming unit 2302 is a first-stage unit used for forming a
magenta(M) image. Similar image forming units 2303, 2304
1S and 2305 are used. for cyan (C), yellow (Y) and black (Bn)
color images.
In the operation of the image forming unit 2302, a
latent image is formed on the photosensitive drum 2318 by
exposure to the laser beam, and a developing unit 2313
2 0 develops the latent image with a toner so as to form a
toner image on the surface of the photosensitive drum 2318.
Numeral 2314 denotes a sleeve which is incorporated in the
developing unit 2313 and which applies a developing bias
voltage to enable development of the latent image with the
2 S toner. A primary charger 2315 charges the photosensitive
drum 2318 to a desired potential. The cleaner 2317 cleans
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the surface of the photosensitive drum 2318 after transfer
of the image, while an auxiliary charger 2316 removes any
residual charge remaining on the surface of the
photosensitive drum 2318 after the cleaning by the cleaner
2317, thereby ensuring that the surface of the
photosensitive drum 2318 is charged in good state by the
primary charger 2315. A pre-exposure lamp 2330 is for
removing residual charges from the photosensitive drum
2318. A transfer charger 2319 effects a discharge from the
reverse side of a transfer belt 2316 so as to transfer the
toner image from the photosensitive drum 2318 onto a
transfer member.
Sheets of transfer members, e.g., paper sheets, are
supplied from cassettes 2309, 2310. A paper feeder 2308
feed the transfer members from these cassettes 2309, 2310.
An absorption charger 2311 causes the transfer member fed
by the feeder 2308 to be absorbed by the transfer belt
2306. A transfer belt roller 2312 serves to drive the
transfer belt 2306 and operates together with the
2 0 absorption charger 2311 so as to enable the transfer belt
2306 to absorb and charge the transfer member.
A charge removing charger 2324 serves to facilitate
the separation of the transfer member from the transfer
belt 2306. A separation charger 2325 has a function for
2 S preventing any disturbance of the image which may be caused
by a separation charging when the transfer member lees the
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transfer belt 2306. Pre-fixing chargers 2326, 2327
compensate for any insufficiency of toner on the transfer
member after the separation, thereby preventing disturbance
of the image. The transfer belt charge removing chargers
2322 and 2323 are used for removing charges from the
transfer belt 2306, thereby to electrostatically initialize
the transfer belt 2306. A belt cleaner 2328 removes
contaminant from the transfer belt 2306.
The fixing unit 2307 thermally fixes the toner image
on the transfer member which has been separated from the
transfer belt 2306 and then passed through the pre-fixing
chargers 2326 and 2327. A paper end sensor 2329 senses the
leading end of the transfer member which has been fed by
the feeder 2308 onto the transfer belt. A detection signal
1$ from the paper end sensor 2329 is delivered from the
printer 2203 to the reader 2201 so as to be used as a sub-
scan synchronizing signal when a video signal is fed from
the reader 2201 to the printer 2203.
<Description of Copying Operation>
2 0 A description will now be given of the copying
operation performed in this embodiment, particularly a
process for preventing forgery by mans of the add-on board
2116 mounted on the copying machine.
Fig. 19 is a flow chart illustrative of the~copying
2 S process performed by the copying machine of this
embodiment. In Step 5101, when there is a demand for add-
CA 02279589 1999-08-23
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on mode, i.e., when a specific operation is conducted by
the operator in the manipulating portion 2115 shown in
Figs. 14 and 15, an add-on mode setting screen as shown in
Fig. 16 is displayed on a liquid crystal display (touch
panel display) which is provided in the manipulating
portion. When there is no demand for add-on mode, another
mode such as a copy stand-by state is displayed.
When add-on mode is used, the ON key on the screen
shown in Fig. 16 is pressed down to set the machine in add-
on mode (5102), and a "secret code" is set on a screen
shown in Fig. 17 (S103). In the display shown in Fig. 17,
the code train consists of numerals alone. This, however,
is only illustrative and the code train can have various
code systems, e.g., alpha-numeric, Japanese kana and Kanji,
if the code input method is suitably changed. The input
code train is stored in a memory section (not shown) which
is a part of the RAM 2113. This input data is maintained
even after the power of the copying machine is turned off,
by virtue of a back-up function.
2 0 When the machine has been set for add-on mode, a
pressing of the copy key (not shown) on the manipulating
portion 2115 (5104) triggers a check as to whether the add-
on board 2116 has been correctly mounted on the body of the
copying machine (5105). If the add-on board has been
2 5 correctly connected, i.e., if the answer to the question
posed in Step 5106 is YES, the copying operation can be
CA 02279589 1999-08-23
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started, whereas, if the connection of the add-on board
2116 is not connected or wrongly connected, i.e., when the
answer NO is given in Step S106, a warning message or an
error message as shown in Fig. 18 is displayed on the
display section (5110), whereby the copying operation is
prohibited (5111).
Subsequently, when the add-on board has been connected
correctly, the process proceeds to Step 5107 in which the
add-on character generating section 2109 develops character
pattern stored in the font ROM 2110, in accordance with the
code data which has been registered and stored in the
memory section which is, in this case, the RAM 2113.
In a subsequent step 5108, whether the OFF key has
been pressed, i.e., whether the add-on mode has been
dismissed, is determined. More specifically, an OFF key
2400 on the display as shown in Fig. 16 is pressed to
dismiss the add-on mode (Step 5109).
If Step 5108 has proved that the instruction for
dismissing the add-on mode has not been issued, the process
2 0 returns to Step 5103 to wait for the entry of a new "secret
code".
As will be understood from the foregoing description,
in this embodiment of the present invention, it is possible
to form a synthetic output image in which a secret code as
2 5 means for indicating that the printed output is a copy
rather than an original is added to the output image. The
CA 02279589 1999-08-23
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secret code can be input and set optionally for independent
copying machine by, for example, a service man or other
administrator, so that the copying machine can be
identified from the copy image produced by the machine.
S Furthermore, the copying machine of this embodiment
automatically prohibits copying operation when the source
of the anti-forgery secret code has been separated from the
copying machine. This effectively prevents any illegal
copying operation during absence of the source of the
secret code which may occur when, for example, the source
of the secret code is being exchanged.
In this embodiment, when the copying machine has been
set for operation in the add-on mode, the secret code is
entered and set through the manipulating portion. This,
however, is only illustrative and the arrangement may be
such that the secret code is beforehand stored in the ROM
2114 on the copying machine and the character patterns
stored in the font ROM are developed on the basis of the
stored secret code.
2 ~ A description will now be given of a first
modification of the third embodiment.
Fig. 20 is a block diagram of a first modification of
the digital color copying machine as the third embodiment.
In this modification, as will be seen from Fig. 20.,
2 5 the font ROM 2110 is separated from the add-on board 2116
and is connected to a system BUS 2111, and the add-on
CA 02279589 1999-08-23
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character generating section 2109 operates to develop
character patterns stored in the font ROM 211, through the
connector 2117.
In this modification, the "secret code" which is to be
added to the output copy image is unchanged even when the
add-on board 2116 is changed.
A description will now be given of a second
modification of the third embodiment.
Fig. 21 is a block diagram of a second modification of
the digital color copying machine as the third embodiment.
Thus, the third embodiment may be carried out such
that the "secret code" is set by an arrangement as shown in
Fig. 21. This copying machine has the same construction as
that shown in Fig. 14, so that the same reference numerals
are used to denote the same blocks as those appearing in
Fig. 14, and description of such blocks is omitted.
In the modification shown in Fig. 21, the "secret
code" is set by means of a dip switch 2150 which is
provided on the add-on board 2116. The I/O 2151 provides
2 0 an interface between the dip switch 2150 and the signal
line 2119.
In this copying machine, an add-on mode setting
display (see Fig. 22) displays the present code which has
ben set through the dip switch 2150. In this case,
2 S however, the code system is composed of a train of
numerals, since the code has been set through the dip
CA 02279589 1999-08-23
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switch. The notation of the code, however, is not limited.
For instance, it is possible to use hexadecimal or decimal
code.
As will be understood from the foregoing description,
the third embodiment of the present invention enables that
a pattern data which has been set optionally is combined
with the read image, so as to enable identification of the
copying machine by which a copy has ben produced.
In addition, copying operation is prohibited when
there is no addition of pattern data, which prevents
dismissal of the anti-forgery function which may otherwise
be caused by absence of the pattern data.
(Fourth Embodiment)
A fourth embodiment of the present invention will be
described with reference to the accompanying drawings.
Fig. 23 is an illustration of a remote administration
system for digital color copying machines as a fourth
embodiment of the present invention. The blocks and
mechanical construction of the copying machine used in this
2 0 system are the same as those of the digital color copying
machine of the third embodiment, so that description of
omitted for these blocks and construction.
Referring to Fig. 23, digital color copying machines
2500 and 2501 are connected to a host computer 2509 which
2 5 is the main control section of this system, through
communication lines 2504, 2505 which may be telephone lines
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and via communication modems 2502, 2503, 2506, 2507. A
communication controller 2508 administrate a plurality of
communication lines so as to control the communication
through these lines. It is assumed here that the above-
S mentioned two communication lines are under control of the
communication controller 2508.
The host computer 2509 control the communication
controller 2508 by an exclusive communication
administration program, thereby administrating the copying
machines 2500, 2501 which are connected to the
communication controller 2508. The communication
administration program monitors the states of the copying
machines 2500, 2501 through the communication lines 2504,
2505, periodically, e.g., once very day at a predetermined
1S time, and gives an inquiry to the copying machine or
machines which use the add-on mode (this may be the same as
that of the third embodiment) to confirm the "secret code"
or "secret codes" stored in such copying machines.
By using the results of the periodical check and
2 0 inquiry, it is possible to confirm whether the "secret
code" is the same one as that registered in the host
computer or a code which has been set at the machine side.
It is thus possible to identify the copying machine by
which a copy has been produced, while conducting a
2 S centralized administration of many copying machines.
(Fifth Embodiment)
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A fifth embodiment which will be described hereinunder
is to provide an effective anti-forgery measure, by the use
of means for storing sections of decision information and
communication means which enable communication of the
stored sections of the decision information.
More specifically, the fifth embodiment is adapted for
storing type of the specific original which is to be
illegally copied and the user's ID code and for displaying
and informing such information through, for example, a
public telephone line. Furthermore, the fifth embodiment
is adapted for storing deciding information of a plurality
of input devices (copying machines) and for displaying and
informing the information via a public telephone line or
through a wireless communication system.
Although a digital color copying machine is
specifically mentioned in the following description of the
fifth embodiment, it is to be understood that the fifth
embodiment can be applied to other types of copying
machines equally well.
2 0 The description will refer to Fig. 24 which is a block
diagram of an image processing system used in the fifth
embodiment, Fig. 25 which is a block diagram of the modem
board in the fifth embodiment, Fig. 26-which is a block
diagram of an image processing apparatus as the fifth
2 5 embodiment, Fig. 27 which is a block diagram of a
normalizing circuit used in the fifth embodiment, and Fig.
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28 which is a block diagram of decision circuit used in the
fifth embodiment. Throughout these Figures, the same
reference numerals are used to denote the same components
or functions. The internal structure of the copying
machine is not described because it is materially he same
as that described before in connection with the first
embodiment with reference to Fig. 1.
Referring to Fig. 24, numeral 3101 denotes an image
scanner, 3102 denotes an interface board, for storing read
image data, 3103 denotes a host computer, 3104 denotes a
still video camera (referred to as "SV"), 3105 denotes a
video taperecorder (referred to as "VTR"), 3107 denotes an
image processing device having a communication function,
3106 denotes a host computer which is placed at a central
administration section, 3108 designates a public telephone
line as an external communication line, 3113 denotes a
modem board through which data is exchanged between the
image processing apparatus and the external communication
line, and S represents a decision signal which is
2 0 transmitted from a memory circuit 3311 in an image
processing section 3114.
Referring to Fig. 25, numeral 3109 designates a CPU
which receives the decision signal S. The decision signal
S is stored in a RAM 3110.. The decision signs l read from
2 5 the RAM 3110 is sent to a MODEM 3111 and is delivered to
the public telephone line 3108,as the communication path,
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by the operation of a communication controller (referred to
as "NCR") 3112.
Referring now to Fig. 26, numeral 3301 denotes an
image input device, 3302 denotes a normalizing circuit,
3303 denotes a circuit for discriminating a specific
original, 3304 denotes a color processing circuit, 3305
denotes an undercolor removing circuit (referred to as
"UCR"), 3306 denotes an image output device, 3307 denotes a
counter portion, 3308 denotes a CPU, 3309 denotes a 24 h
power supply as a back-up power source, 3310 denotes an
operating portion, 3311 denotes a memory circuit and 3312
denotes a display section for displaying stored data.
Referring to Fig. 27, numerals 3301 to 3309 denote
multipliers, while 3310 to 3312 denote adders.
As a result of operations of the circuits shown in
Figs. 1, 24, 25, 26 and 27, a color image is read by the
image scanner 3101 and is color-separated into digital
images of three colors R, G and B. The thus obtained image
signals are delivered to the IPU 3102 and to a device
2 0 having an image processing function, e.g., a host computer
3103. The IPU 3102 and the host computer 3103 perform
ordinary image processing operations such as logarithmic
conversion, masking computation and CUR. Consequently, the
R, G and B image signals are converted into Y, M, C and Bk
2 S signals. In particular, the host computer 3103 can handle
the image in various color spaces such as XYZ space and
CA 02279589 1999-08-23
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L*a*b* space. Therefore, the host computer 3103 can
deliver signals of all type of color spaces to the image
processing apparatus 3107. The R,G and B signals which
are input from SV 3104, VTR 3105 and the image scanner 3101
are to be considered to be of different types of signals
when read with different spectral characteristic. Thus,
the image processing apparatus 3107 receives image data of
various color spaces. The image processing apparatus 3104
has a construction which is the same as that shown in Fig.
2. The signal delivered from the image input device 3301
includes an 8-bit image signal I and an additional
information signal h. The additional information signal h
is a signal indicating the color space to which the input
image signal belongs, and is used also as a matrix for a
later-mentioned conversion. These input signals are
delivered to the normalizing circuit 3302 which, in
accordance with the additional information signal h,
converts the input image signal I into a color space of a
color taste matching data which is stored beforehand in the
2 0 decision circuit 3303. It is assumed here that the
aforementioned matching data is R, G and B signals
according to NTSC (National Television System Committee)
system. In such a case, the R, G and B signals can be
converted into three stimulus values X, Y and Z of XYZ
2 S color specification system, in accordance with the
following formula (2). These three stimulus values X, Y
CA 02279589 1999-08-23
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and Z are further converted into L*, a* and b* values of
L*a*b* color specification system, in accordance with the
following formula (3):
X 0.6067 0.1736 0.2001 R
Y - 0.2988 0.5868 0.1144 G " .(2)
Z 0.0 0.0661 1.1150 B
L* = 116 (Y/Yp) 1/3 - 16
1 0 a* = 504 .3 [ (X/Xp) 1/3 - (Z/ZO) 1/3]
b* = 201 .7 [ (Y/Yp) 1/3 _ (Z/ZO) 1/3~
(Xp, Yp, Zp = CONST) ....... (3)
The image signal I and the additional information
signal h which are output from the image input device 3301
are delivered to the normalizing circuit 3302. The
construction of the normalizing circuit 3302 is shown in
Fig. 26. When the image signal I is given in the form of
three stimulus values X, Y and Z of the XYZ color
2 0 specification system, these values X, Y and Z are delivered
to the multipliers 3321 to 3329. Values all to a33 are
written in the multipliers from the additional.information
signal h. The outputs from the multipliers 3321 to 3329
are delivered to the adders 3330 to 3332 as illustrated and
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are output from these adders as signals R, G and B. These
conversions are expressed by the following matrix:
R all a12 a13 X
G _ a21 a22 a23 Y
B a31 a32 a33 Z
............ (4)
The 3 x 3 matrix which forms the right side of the
formula (4) is an inverse matrix of the matrix of
coefficients which are used in the formula for converting
R,G,B signals under NTSC system into three stimulus values
X,Y,Z of the XYZ color specification system. Thus, when
the signals are of different color spaces or when the same
color space is used but distortion of axes has been caused
due to influence of spectral characteristics of the reading
system, coefficients for conversion into standard signals
such s R,G,B signals under NTSC system are input as the
additional information together with the image signals,
thus normalizing the input signals, whereby the signals are
converted into those of a predetermined color space to
2 0 which the matching data stored in the decision circuit 3303
belongs.
The output from the normalizing circuit is divided
into two sub-systems: one is given to the color processing
circuit 3304, while the other is sent to the decision
2 5 circuit 3303. The R,G and B signals delivered to the
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color processing circuit 3304 are subjected to processings
such as logarithmic conversion, masking computation and
UCR, and are delivered in the form of screen-sequential
signals Y, M, C and Bk into the UCR circuit 3305.
Meanwhile, the signals delivered to the decision circuit
3303 is checked for presence of image of any registered
specific original in the input signal, by a method which
will be described later. Symbol INH represents the result
of the decision. When the image of any registered specific
original is found, 1 is delivered as the decision result
INH to the UCR circuit 3305, whereas, when no such image is
found, 0 is delivered to the UCR circuit 3305. When
decision result INH is "1", the undercolor removing circuit
3305 delivers the image signal to the image output device
3306 with the Bk portion changed into solid black image.
At the same time, signals are delivered to the memory
circuit 3311 which indicate the degree of probability of
decision (probability of presence of the image of a
specific original), type of the candidate specific
2 0 original, ID number of the user or operator, and so forth.
In the memory circuit 3311, a signal S from the CPU
3308 is delivered to the MODEM board 33113 and is further
transmitted therefrom to the host computer 3106 through the
public telephone line 3108. Conversely, when the~decision
2 5 result INH is "0", the image processing process is set to
"thru" mode so that the output from the color processing
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circuit 3304 is delivered to the image output device 3306
which produces a hard copy by a printing technique such as
electrophotography, thermal transfer or ink jet printing.
Thus, in this embodiment, a hard copy true to the
original cannot be produced when the read image contains an
image of any registered specific original.
A description will now be given of the operation of
the decision circuit 3303. The decision circuit 3303 is
composed of a color space matching circuit (Fig. 28) and a
decision signal generating circuit (Fig. 33). Thus, the
construction of the decision circuit 3303 is as shown in
Figs. 28 and 33.
Referring to Figs. 28 and 30, numeral 3401 designates
data of significant 5 bits in the 8-bit R (red) signal
derived from the normalizing circuit 3302. Similarly,
3402 and 3403 denote significant 5-bit data of G (green)
and B (blue) signals. Numeral 3404 designates a ROM (Read
Only Memory) which stores information concerning the color
taste of each of a plurality of specific originals. The
2 0 aforementioned R, G and B signals are input to the
addresses Ap to Alq, and decision signals indicative of
whether these R,G and B signals conform with the color
taste of specific originals are delivered as data Dp to D~.
A PROM 3404 stores information concerning color tastes
2 5 of specific originals in the form of R, G and B signals
following NTSC system. When the input R,G and B signals
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conform with the color tastes of specific originals, "1" is
output as the data Dp to D~, otherwise "0" is delivered to
the same. These outputs Dp to D~ are delivered for each of
the color space decision circuits 3420 to 3427.
Fig. 30 illustrates the relationships between the data
of a plurality of specific originals stored in the PROM
3404 and bit positions in the PROM 3404. It will be seen
from this Figure that decision result information (0 or 1)
concerning 8 types of specific originals (originals A to H)
are delivered in a bit-parallel manner from the outputs Dp
to D~.
Numerals 3410 to 3417 denote smoothing circuits which
perform smoothing operations shown in Figs. 30 and 31 on
the color taste deciding signals Xp to X7. Numerals 3901
to 3907 indicate AND gates, while 3910 designates an OR
circuit.
Fig. 31 is a block diagram of each of the smoothing
circuits 3410 to 3417. In this Figure, numeral 3701, 3702
denote multipliers, 3703 denotes an adder, 3704 denotes a
2 0 flip-flop and 3705 denotes a comparator.
Fig. 32 illustrates the relationship between the input
Xn and the output value Yn obtained through the smoothing
operation. It will be seen that the value of the output
Yn increases when "1" is successively input as the inputs
2 S Xn. Conversely, the value of the output Yn progressively
decreases when Xn is 0. When the R, G and B signals input
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to the apparatus conform with the color tastes of one of
the registered originals, "1" is successively input as the
inputs Xn so that the output value Yn increases until it
exceeds a predetermined level.
S The outputs Cp to C~ of the smoothing circuits are
obtained by binarizing the output Yn with a predetermined
threshold value. Thus, "1" is successively delivered from
the outputs Cp to C7 only when successive pixels conform
with the color tastes of one of the registered specific
originals, whereby the reliability of decision is enhanced.
Numerals 3420 to 3427 denote color space decision
circuits which compute, in real time, the degrees of
similarity between the input color signals and the data of
specific originals in terms of the RGB color space values.
The degrees of similarity are output in the forms of
decision signals MKp to MK7.
Fig. 29 is a block diagram of one of the color space
decision circuits 3420 to 3427. In this Figure, numeral
3501 denotes a NOT circuit, 3502 denotes an AND circuit,
2 0 3503 denotes an OR circuit, 3504 denotes a counter, 3505
denotes a maximum value holding circuit, 3506 denotes a
register and 3507 denotes a comparator.
The OR gate 3503 computes OR of the data Dn from the
SRAM 3430 and the signal Cn derived from the smoothing
2 5 circuit, and the result of the computation is written again
in the SRAM 3430 as the data Dn.
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Meanwhile, the AND gate 3502 computes AND of the data
Dn, signal Cn and the data Xn from the PROM 3404. The AND
gate 3502 produces an output "1" only when the data Dn is
being changed from "0" to "1" while the data Xn and Cn are
S "1". The counter starts up-counting in response to the
output "1" from the AND gate 3502. This counter 3504 is
cleared by each rise of the sub-scan section signal VS.
The maximum value of the counter output which is the output
from the maximum value holding circuit 3505 is compared by
the comparator 3507 with a predetermined constant 8n.
When the maximum value exceeds this constant value 8n, the
comparator 3507 produces an output "1" as the signal MKn,
otherwise it produces "0" as the signal MKn. The constant
value 8n is set as the percentage (~) S of the volume
1$ occupied by the color taste of the specific original in the
color space.
More specifically, representing the number 1 in the
PROM 3404 shown in Fig. 29 by Vorg, Vorg is determined by
the following formula ~(5)
8n = Vorg x S/100 ........... (5)
The value S in the formula shown above is determined
such that the decision signal MKn becomes "1" when about
2 5 half of a specific original laced on the document table of
the copying machine has been read.
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As a result o the processing described above, the
color space similarity decision signals MKp to MK~ are set
to "1" when the input image data substantially conforms
with data of one of the specific documents in terms of
values on the RGB tertiary color space.
Fig. 33 shows the construction of the aforementioned
decision signal generating circuit.
When input image data is determined to conform with
the data of any one of the registered specific originals
stored in the PROM 3404, the decision signal INH is changed
into "1" in real time and is fed back to the undercolor
removing circuit 205 without delay.
In the foregoing description of the fifth embodiment,
the image input device 3301 delivers X, Y and Z signals of
XYZ color specification system, and these signals are
converted into R,G and B signals under NTSC system. This,
however, is only illustrative and input image signals of
any color spaces, such as M, Y, C and Bk color signals or
L*a*b* color space signals can be converted into color
2 0 signals of the same color space as the matching data stored
in the decision circuit 3303 by the addition of the
additional information, thereby to prohibit copying of any
original which should not copied from legal point of view.
Fig. 39 is a block diagram of the copying machine used
2 5 in this embodiment. A CCD color sensor 5001~reads, in a
line-by-line fashion, a color original which is not shown,
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and delivers the read data to an analog amplifier 5002.
An A/D converter 5003 sample-holds the analog output of the
analog amplifier 5002 and converts the same into digital
data. A shading correction circuit 5004 effects a
correction for any gradient of brightness due to position
of reading of the original, as well as for any unevenness
of sensitivity of the CCD sensor. Numerals 5005. 5006 and
5007 denote, respectively, a logarithmic conversion
circuit, a black component extraction circuit and a
masking/UCR circuit which perform known color correction
processings for changing the RGB signals into YMCBk signals
suitable for the printer used as the output device.
Numeral 5008 designates a circuit for generating reading
synchronizing signals HS, CLK and VS. These synchronizing
signals are delivered to all circuit blocks. For
information, HS represents a main scanning section signal,
CLK represents a fundamental clock signal for reading the
image on pixel basis and VS represents a section signal
indicative of the effective region in the direction of the
2 0 sub-scan. Numeral 5009 designates a normalizing circuit
which normalizes the input image signals into spectral
characteristic or color space conforming with that of the
matching data stored in a discrimination circuit 5012.
Numeral 5010 designate a color space matching circuit which
2 5 performs a real-time computation of the similarity between
the read image data and the color space of each specific
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original. Numeral 5011 designates a decision signal
generating circuit which produces a signal "1" when the
color space matching circuit 5010 has determined that one
of the specific originals is being read, otherwise the
circuit 5011 generates an output "0"
The decision output signal from the circuit 5011 is
delivered to, for example, the masking/UCR circuit 5007.
Consequently, when any original which should not be copied
from a legal point of view is being read, the masking/UCR
circuit deviates the masking coefficients from correct
values, thereby degrading the color reproduction of the
copy output, thus impeding any attempt of forgery.
Fig. 35 is a circuit diagram of the counter portion
3307 shown in Fig. 26. In this Figure, numerals 4310 to
4317 and 4320 to 4327 denote flip-flops, 4330 to 4337
denote AND gates, 4340 to 4347 denote inverters and 4300 to
4307 denote 12-bit counters.
When one of the color space decisions signals MKp 4004
to MK~ 4007 is -changed from "0" to "1", corresponding 12-
2 0 bit counter, i.e., one of the counters 4300 to 4307, starts
to up-count. Thus, a counter is used for each of the
decisions signals MKp to MK~, so that decision is performed
for each of a plurality of specific originals.
The counters 4300 to 4307 are cleared by the CPU 3308.
2 5 More specifically, the counters 4300 to 4307 are cleared
only when specific code is input through a secret code key
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and ten keys on the operating portion 3301 shown in Fig.
37.
The counter portion 3307 is always supplied with
electrical power from the 24-h power supply 3309 (back-up
power source), so that the contents of the 12-bit counters
4300 to 4307 are retained without being lost even when the
power of the copying machine has been turned off.
Fig. 34 shows the flow chart illustrative of the
operation of the CPU 3308.
Figs. 37 and 38 illustrate examples of message which
is displayed when the copying operation should not be
performed.
When a copy key 4501 in the operating portion 3301 is
pressed (51401), the CPU 3308 reads the values of the
counters 1300 to 1307 shown in Fig. 35 (Step 51402) and
determines whether the maximum value of the counter
contents exceed the predetermined value n. If the value n
is exceeded, the process proceeds to Step 51404 in which a
message shown in Fig. 37 indicative of illegal use is
2 0 displayed. Conversely, when the maximum value n is not
exceeded, the process proceeds to Step 51405 in which
copying operation is executed and, in Step S1406, the
contents of the counters 4300 to 4307 are examined.. If the
result of the examination has proved that the values in the
2 5 counters have increased from the values which were read in
Step 51402, the process proceeds to Step 51407 in which the
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message of Fig. 38 indicating illegal use is displayed. In
addition, in Step 51408, the same message or an equivalent
information is transmitted to the host computer in the
administration center trough, for example, a public
telephone line.
Fig. 36 is a top plan view of the manipulating portion
3310. The operating portion 3310 has a liquid crystal
display portion 4504, a ten-key device 4503, and a secret
code key 4502. The operator can enter a specific code by
suitably manipulating the ten-key and the secret code key,
so that the values in the counters 4300 to 4307 are
displayed.
According to the process described hereinabove, it is
possible to administrate and monitor information concerning
each of a plurality of type of specific originals, whereby
the reliability of anti-forgery function can be enhanced.
As will be understood from the foregoing description,
the fifth embodiment of the present invention stores
deciding information together with other information, thus
2 ~ enabling a service man or other user to check the content
of the information at the time of, for example, a
periodical check. In addition, the decision information on
a plurality of copying machines can be monitored and -
administrated concentrically from an administration center,
2 5 thus offering a greater coverage of anti-forgery monitoring
system.
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(Sixth Embodiment)
Fig. 40 illustrates a block diagram of a counter
section used in a sixth embodiment of the present
invention, while Fig. 41 illustrates select signals and
type of the input device used in the sixth embodiment.
While the fifth embodiment described before is
intended for storing decision information for each of a
plurality of types of specific originals, the sixth
embodiment is intended for storing decision information on
the basis of the image input device.
A description will be given of the construction of the
counter section used in this embodiment.
Referring to Fig. 40, numeral 5721 and 5722 denote
flip-flops, 5723 denotes an inverter, 5724 and 5730 to 5733
denote AND gates and 5701 to 5704 denote counters.
Select signals 5705 (se00 to se03) are signals which
are under the control of the CPU 5750 and which are
indicative of the machine from which image data is being
entered. Counters 5701 to 5704 are adapted for reading the
2 0 decision information for the respective machines. The
contents of these counters are read by the CPU 5750. Fig.
41 is an illustration of the relationships between the
select signals 5705 (se00 to se03) and. the machines through
which the image data are entered. According to this
2 5 arrangement, decision information is stored for each of a
plurality of copying machines, so that the prevention of
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forgery can be effected on the basis of the individual
copying machine.
In this embodiment, masking coefficients are deviated
from correct values when the input image contains an image
approximating the image of one of a plurality of specific
originals, so as to degrade the quality of the produced
copy. This, however, is only illustrative and various
invalidation measures such as blackening of a portion of
the image, add-on of line patterns or the like may be
adopted to make the copy unusable, upon detection of the
presence of an image similar to the image of any one of the
registered specific originals.
It is also possible to completely disable the copying
machine by stopping a processing function such as motor
1$ operation in the copying machine.
In order to inform the fact of any illegal use of the
coping machine, it is possible to use various communication
functions such as a wireless communication device or a LAN
(Local Area Network), as well as public telephone line
2 0 which is employed in the described embodiment.
(Seventh Embodiment)
A seventh embodiment of the present invention employs
a copying machine which is the same as that shown in Fig.
2. The construction of the copying machine is therefore
2 S omitted.
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The seventh embodiment is discriminated from the first
embodiment by the construction of the image scanner. The
construction of the image scanner used in this embodiment
will be described hereinunder.
Fig. 42 is a block diagram of an image scanner 201
used in the seventh embodiment. Numerals 6001 to 6010
denote signal lines, 6210-1, 6210-2 and 6210-3 respectively
denote CCD sensors (solidstate imaging devices) having
spectral sensitivity characteristics of red (R), green (G)
and blue (B). These CCD sensors respectively produce 8-bit
outputs 0 to 255 after an A/D conversion.
The CCD sensors 6210-1, 6210-2 and 6210-3 are disposed
at a predetermined positional interval. In order to
compensate for the spatial offset, delay elements 6401 and
1$ 6402 are used to eliminate any time difference of the
output signals of these sensors due to difference in
positions.
Numerals 6403, 6404 and 6405 denote logarithmic
converters, each of which is composed of a look-up table
2 ~ ROM or RAM and converts an illuminance signal into a
density signal. Numeral 6406 denote a masking/UCR circuit
which is known per se. This circuit outputs magenta (M),
cyan (C),yellow (Y) and black (Bk) signals in response to
input three signals R, G and B, in the form of a bit signal
2 S of a predetermined bit length, e.g., 8 bits, in a frame-
sequential manner.
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A signal CNO is a 2-bit screen-sequential signal which
is a control signal indicating the sequence of four reading
cycles. Fig. 66 is a diagram showing the relationship
between the CNO signal and the print output. The CNO
signal serves to change-over the conditions of operation of
the masking/UCR circuit 6406 shown in Fig. 66.
Numeral 6407 denotes a spatial filter which is known
per se and which performs correction of space frequency of
the output signal. Numeral 6408 denotes a density
conversion circuit which has a function for correcting the
density characteristic of the printer which corresponds to
the printer 202 shown in Fig. 2. The density conversion
circuit 6408 is composed of a ROM or a RAM similar to the
logarithmic converters 6403 to 6405.
Numeral 6405 designates a decision circuit for
deciding whether an image which is being entered conforms
with the image of any one of a plurality of registered
specific originals. This circuit delivers the result of
the decision in the form of a decision signal H which is
2 0 "0" or "1". Namely, when the image which is being entered
is determined to conform with the image of one of the
registered specific originals, the deciding signal H is set
to "1", otherwise to "0".
The decision circuit 6409 also receives the aforesaid
2 5 CNO signal. The decision criterion is changed for each of
four reading cycles so as to enable decision for each of a
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plurality of types of specific originals. numeral 6410
designates an OR gate which conducts an OR computation of
the 8-bit output V from the density conversion circuit 6408
and the decision signal H output from the decision circuit
6409, and produces an output V'.
Consequently, when the decision signal H is "1", i.e.,
when the image which is being read conforms with the image
of one of the registered specific originals, the OR gate
6410 delivers a hexadecimal signal V' - FF (=255)
regardless of the level of the input signal V, whereas,
when the decision signal H is "0", i.e., when the image
which is being read does not conform with any one of the
images of the registered specific originals, the OR circuit
6410 produces the input signal V as the output signal V'/
Referring to Fig. 1, numeral 6411 denotes a
semiconductor chip which integrates the masking/UCR circuit
6406, decision circuit 6409 and the OR gate circuit 6410.
The semiconductor chip 6411 is a single-chip LSI as shown
in Fig. 43. It is therefore impossible to by-pass the
2 0 decision circuit 6409 alone.
In this embodiment, the semiconductor chip 6411, i.e.,
the LSI, is formed of a gate array which is a kind of ASIC,
so that the semiconductor chip 6411 is constructed as a
module or a unit.
2 5 This embodiment has a thinning circuit and a frequency
dividing circuit which have the same constructions as those
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explained before in connection with the first embodiment
with reference to Figs. 5 and 6. The thinning circuit and
the frequency dividing circuit are therefore not detailed.
A description will now be given of the decision
S circuit 6409 used in this embodiment.
Fig. 44 is a block diagram showing the construction of
the decision circuit 6409 used in the seventh embodiment.
In this Figure, numeral 6301 denotes a thinning circuit
which may be the same as that shown in Fig. 5. This
circuit performs thinning of the data in order to reduce
the load of the decision circuit 6409 as the processing
circuit. Numeral 6302 designates a color taste look-up
table used in the seventh embodiment. The seventh
embodiment is different from the first embodiment in that
it performs decision for each print color in accordance
with the signal CNO.
Obviously, the color taste matching look-up table 6302
can be constituted by a mask ROM constructed in the gate
array 6411. This table performs determines matching of
2 0 color taste as a factor of the image characteristic, with a
plurality of types of specific originals which have ben
registered beforehand. The color taste matching look-up
table-6302 stores the results of examination of color taste
distributions of 32 types of specific originals and holds
2 5 the results of decision as to whether the color tastes of
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pixels conform with any one of color tastes of these
specific originals.
More specifically, the look-up table 6302 has 17 bits
including significant 2 bits allocated for the CNO signal
S as the frame-sequential signal and less significant 15 bits
used for significant 5 bits of R,G and B image signals
after thinning. For each of the values 0 to 3 of the CNO
signal, whether the color taste of a pixel corresponds to
the color taste of a specific original is determined for
each of the 8 types of specific originals and the results
are simultaneously output in the form of 8-bit signals.
Consequently, color taste matching operation is conducted
fro 32 types of specific originals by four reading scanning
cycles.
1S Numerals 6303-1, 6303-2, ...., 6303-8 denote color
taste decision circuits which have an identical hardware.
More specifically, each color taste decision circuit
includes an integrator 6306, a register 6307 and a
comparator 6308, and performs a decision as to whether the
2 0 image of any one of the registered specific originals
exists in the read image.
Numeral 6309 designates a logical OR circuit which
produces a decision signal H of "1" level; when at least
one of the color taste decision circuit 6303-1 to 6303-8
2 S has determined that an image of a registered specific
original exists in the read image.
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The integrator 6306 of this embodiment has
construction and input/output function substantially the
same as those of the integrator used in the first
embodiment (see Fig. 7). Detailed description of the
integrator 6306 is therefore omitted.
The result of the processing performed in this
embodiment is substantially the same as that explained in
connection with the first embodiment with reference to Fig.
11.
(Eighth Embodiment)
Fig. 45 is a block diagram of an image scanner used in
the eighth embodiment of the present invention. Fig. 46 is
a block diagram showing the construction of a critical
portion of the image scanner shown in Fig. 45. Fig. 47 is
a timing chart illustrating timings of data handled in the
seventh embodiment. Fig. 48 is a block diagram of a 2-bit
counter used in the eighth embodiment. Fig. 49 is a block
diagram showing the construction of a decision circuit used
in the eighth embodiment. In Fig. 45, the same reference
2 0 numerals and the same signal symbols are used to represent
same circuit components and signals shown in Fig. 42
showing the seventh embodiment.
Numerals 7001 to 7010 denote signal lines, while 7900
denotes a 2-bit counter.
2 5 A critical feature of this embodiment resides in the
use of a semiconductor chip 7411 shown in Fig. 45. This
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semiconductor chip 7411 is adapted to effect masking and
UCR operations on the YMC signals carried by the signal
lines 7001 to 7003, without inputting the CNO signal to the
masking/UCR circuit 7406. At the same time, this
semiconductor chip 7411 delivers to the decision circuit
7409 both the CNO signal and a later-mentioned VCNT signal,
thereby obtaining the decision signal H.
As will be sen from Fig. 48, a VCNT signal is
generated by a 2-bit counter 7900 which receives the main '
scan synchronizing signal HSYNC. Namely, the VCNT signal
counts up from 0 to 3 for each of the main scanning cycle,
i.e., in response to one step of the sub-scan, and repeats
this counting again and again from 0 to 3.
In the seventh embodiment described before, the
decision criterion is switched in accordance with the value
of the CNO signal so as to perform decision for each of 32
types of the registered specific originals. In the eighth
embodiment, both the frame-sequential signal CNO and the
VCNT signal are input to significant addresses of the color
2 0 taste matching look-up table 7302 as shown in Fig. 49,
whereby decision is possible for up to 128 types of
registered specific originals.
Thus, the eighth embodiment can conduct check up of
the images for a large number of types of specific
2 S originals which is 4 times as large that handled by the
seventh embodiment, although the construction of the eighth
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embodiment is not so much changed from that of the seventh
embodiment.
Obviously, the present invention can be carried out in
such a manner that the switching of the decision criterion
S is conducted in response to the CNO signal alone.
(Ninth embodiment)
In the seventh embodiment described before, the
decision criterion is changed by the frame-sequential
signal, whereas, in the eighth embodiment, the switching of
the criterion is performed for each main scan. These
manners of switching of the decision criterion, however,
are not exclusive, and the invention may be carried out in
such a manner that the decision criterion is switched for
each of successive pixels, as in the ninth embodiment which
1S will be described hereinunder.
Fig. 50 is a timing chart illustrating timings of data
handled in the ninth embodiment. Fig. 51 is a block
diagram showing the construction of a 2-bit counter used in
the ninth embodiment.
2 0 A substantially same effect can be obtained by using,
as the VCNT signal used in the eighth embodiment, the VCNT2
signal obtained by inputting the pixel clock signal CLK of
Figs. 12A and 12B to a 2-bit counter.
(Tenth Embodiment)
2 S In the tenth embodiment of the invention, the anti
forgery function is performed by circuits which are
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composed of a plurality of LSIs. The tenth embodiments
employ various components which are the same as those used
in the seventh embodiment. These components are therefore
denoted by the same reference numerals as those appearing
in Fig. 42 and detailed description of such components are
omitted.
Fig. 52 is a block diagram of an image scanner used in
the tenth embodiment.
Numerals 8001 to 8017 in Fig. 52 denote signal lines.
The tenth embodiment employs a first chip 8301 as a first
LSI. The first chip 8301 integrates a masking/UCR circuit
8406, thinning circuit 8401, frequency dividing circuit
8402, decision circuits 8411 to 8418 and OR gates 8420 to
8421. Thus, all the circuits for deciding presence of
specific original used in the seventh embodiment, except
for the color taste matching look-up table, are integrated
in the first chip 8301.
Numeral 8302 denotes a second chip as a second LSI
which integrates a space filter 8407 and a color taste
2 0 matching look-up table 8303. In order to attain a high
degree of decision precision, 5 bits are allocated for each
of the pixels.
In order to improve the precision of decision or to
increase the number of types of the specific originals to
2 5 be detected, it is effective to increase the capacity of
the color taste matching look-up table by dividing the LSI
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into first and second chips 8301 and 8302 as illustrated in
Fig. 52. Obviously, however, the division of the LSI into
a plurality of separate LSIs may be conducted for other
purposes than described above.
As will be understood from the foregoing description,
in the tenth embodiment of the present invention, part of
the image signal processing section and whole or part of
the image decision section are constructed on a common LSI.
Therefore, any attempt for removing the anti-forgery
function essentially removes a part of the function of~the
image processing section. so that the copying image signal
processing function is failed, with the result that the
copying machine does not operate. It is thus possible to
completely reject any attempt for forgery.
It is to be understood that the present invention can
be carried out in the form of an LSI chip which carries, as
described, part of the image signal processing portion and
the whole or part of the image deciding section, as well as
the whole copying machine incorporating such an LSI chip.
2 0 It is also to be understood that the same effect as
that offered by the tenth embodiment can be obtained when
part of the image processing section and the whole or part
of the image deciding section are formed on the same
printed board, although in the tenth embodiment they are
2 5 formed on a single LSI chip.
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Furthermore, the tenth embodiment may be modified such
that at least a part of the image deciding section is
formed on the same LSI chip or a circuit board as s
component which controls the copying process of the
machine, e.g., a microprocessor, necessary for the copying
operation. It will be clear that such a modification
offers the same advantage as the tenth embodiment in which
at least a part of the image deciding portion is formed on
the same LSI chip or board as a part of the image '
processing section.
(Eleventh Embodiment)
A description will now be given of an eleventh
embodiment of the present invention. Although a copying
machine is specifically mentioned in the following
description, it is to be noted that the invention can
equally be applied to other types of apparatuses such as a
facsimile apparatus, printer and so forth.
The general construction of the copying machine is not
described because it is materially the same a that
2 0 explained before in connection with the first embodiment
with reference to Fig. 1.
The eleventh embodiment employs an image scanner which
is different from those employed in the first embodiment
and the seventh to tenth embodiments. This image scanner
2 S will be described hereinunder.
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Fig. 54 is a block diagram showing the construction of
the image scanner used in the eleventh embodiment, while
Fig. 55 is a block diagram showing critical portion of the
image scanner shown in Fig. 54. Fig. 56 is a timing chart
illustrating the timing of data used in the eleventh
embodiment.
In Fig. 54, components which are the same as those
used in the seventh embodiment are denoted by the same
reference numerals as those in Fig. 42. In Fig. 54,
numerals 9001 to 9012 denote signal lines.
Numeral 9450 denotes a CPU which commands the whole
apparatus and which produces a CNO signal which will be
described later with reference to Fig. 66. Numeral 9451
designates a ROM storing a program, while 9452 designates a
1$ RAM which is used as a work area of the CPU 9450.
The CNO signal serves to change-over the operating
conditions of the masking/UCR circuit 6406 at the timing
shown in Fig. 56, under the control of the CPU 9450.
Referring to Fig. 54, numeral 9411 designates a
2 0 semiconductor chip in which a masking/UCR circuit 6406 and
an identification signal adding circuit 9410 are
integrated. This chip has the form of a one-chip LSI as
shown in Fig. 55. Therefore, according to the arrangement
shown in Fig. 54, it is difficult for the identification
2 5 signal to by-pass only the identification signal adding
circuit 9410.
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In the illustrated embodiment, for example, the LSI of
the semiconductor chip 9411 is constructed as an integral
unit from a gate array which is a kind of ASIC.
<Signal Adding Circuit>
Fig. 57 is a block diagram showing the construction of
the identification signal adding circuit used in the
eleventh embodiment. In this Figure, numeral 9901 denotes
a sub-scan counter, 9902 denotes a main-scan counter, 9903
denotes a look-up table ROM (referred to as "LUT"), 9905
denotes a flip-flop, 9913 denotes an AND gate, 9906 denotes
a register, 9910 denotes a 4 to 1 selector, 9911 denotes an
AND gate, and 9912 denotes an adder.
The sub-scan counter 9901 and the main-scan counter
9902 count, respectively, the main scan synchronizing
1$ signals HSYNC and the pixel synchronizing signals CLK on 9-
bit unit, i.e., at 512 periods. The LUT 903 is a read-only
memory (referred to as "ROM") which holds a pattern to be
added, and receives less significant 6 bits of the contents
'of the sub- and main-scan counters 9901 and 9902. Only
2 0 one bit of the output from the LUT 9903 is referred, and a
logical product of this bit and significant 3 bits of the
main- and sub-scan counters 9902 and 9901 is computed by an
AND gate 9904. The output is delivered to the flip-flop
9905 which synchronizes this output by means of the CLK
2 5 signal. The synchronized output is delivered to the AND
gate 9913 which computes AND of this output and the 2-bit
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frame-sequential signal CNO "0" and CNO "1". The result is
supplied to the AND gate 9911. The resultant signal is
CNO = 2, i.e., a signal which is effective only when the
printing is being done in yellow color (see Fig. 66)
S Meanwhile, the register 9906 holds a value P1. The
data which has been transmitted through the AND gate 9913
is supplied to the AND gate 9911 which computes AND of this
data and the value P1, and the pattern obtained as a result
is added to the input signal V by means of the adder 9912.
The adder 9912 delivers V' which represents the result of
addition of the pattern to the input signal V. Therefore,
the pattern held by the LUT is repeatedly read and added to
the signal V to be output when the signal CN = 2 is being
obtained, i.e., when the printing is being done in yellow
1 S color .
Thus, the pattern added is printed only in yellow
color. This is because human eyes generally have small
ability of recognition of pattern formed in yellow color.
(Result of Copying)
2 0 Fig. 58 illustrates an example of the result of the
copying operation performed in the eleventh embodiment. In
this Figure, the pattern which has been added is denoted by
9101. The content of this pattern has been held in the LUT
9903. In the example shown in Fig. 58, a pattern composed
2 5 of "ABCD" and "1234" arrayed in the direction of the sub-
scan are added by 64-pixels in the direction of main-scan
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and 64-pixels in the direction of sub-scan. This pattern
is placed repeatedly for each 512 pixels in the direction
of the main scan and for each 512 sub-scan lines. By
forming different patterns for different machines, e.g., in
S the form of a train of numerals representing the production
serial No. or a code representing the serial No., it is
possible to identify each machine from the pattern formed
on the copy produced by the machine.
The arrangement may be such that the pattern added is
made clearer and more distinguishable when there is a large
probability that the read image contains the image of one
of specific originals which are not to be legally copied.
In this embodiment, the pitch of addition of the
pattern is 512 pixels (or lines) in the direction of the
1$ main scan. In this embodiment, the resolution is 400 dpi
(dots/inch), so that the pattern is added at a pitch of
about 32.5 mm. Typical bill issued from the Bank of Japan
has a width of about 76 mm. Widths of bills of other major
countries also fall within the range between about 60 mm
2 0 and 120 mm. Consequently, the above-mentioned pattern is
printed without fail on any copy of such a bill. Even when
the portion of a copy corresponding to the bill is cut out
and used for an illegal purpose, it is possible to identify
the copying machine used for the production of the copy by
2 S reading the added pattern through an examination.
(Twelfth Embodiment)
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A description will now be given of a twelfth
embodiment of the present invention.
Fig. 59 is a block diagram of an image scanner used in
the twelfth embodiment of the present invention. Fig. 60
is a block diagram showing a critical portion of the image
scanner shown in Fig. 59.
In the eleventh embodiment described above, the
masking/UCR circuit 6406 and the identification signal
adding circuit 9410 are constructed on a single
semiconductor chip 6420, as shown in Fig. 54.
In contrast, in the twelfth embodiment of the present
invention, an image processing circuit for generating image
reproduction signals from the input R, G and B signals,
including the logarithmic conversion circuits 6403 to 6405,
masking/UCR circuit 6406, space filter 6407 and the density
conversion circuit 6408, is integrated with an
identification signal adding circuit 9410 on a single
semiconductor chip 9601. According to this arrangement, it
is impossible to isolate the identification signal adding
2 0 circuit 9410 from the signal processing circuit, so that
the machine cannot be used when the identification signal
adding circuit has been isolated.
(Thirteenth Embodiment)
A description will now be given of the thirteenth
2 5 embodiment of the present invention.
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While the eleventh and twelfth embodiments described
before employ multi-value printers, the use of such a type
of printer s only illustrative and the invention may be
carried out by employing a different type of printer such
as a binary printer of bubble-jet type.
In the case of a binary printer such as a bubble jet
printer, any added information printed in yellow color is
easily noticeable and, hence, degrades the quality of the
product image. In the thirteenth embodiment, therefore,
the identification information is given in the form of a
specific pattern formed by binary signals.
Fig. 61 is a block diagram of an image processing
circuit incorporated in a full-color copying machine as the
thirteenth embodiment. The image processing circuit shown
1$ in this Figure includes a line sensor 13101, A/D converter
13102, shading correction circuit 13103, density conversion
circuit 13104, masking/UCR circuit 13108, ink heads 13109a,
13109b, 13109c, 13109d, a pattern detection/correction
circuit 13110, pattern adding circuit 13111 and a pattern
2 ~ generating circuit 13112.
Fig. 62 is a block diagram showing a critical portion
of the circuit shown in Fig. 61.
The operation of this embodiment will be described
hereinunder.
2 $ In operation, an original (not shown) is illuminated
by light to reflect the light. The reflected light is
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converted into color-separated electrical signals red,
green and blue (R, G and b) by the line sensor 13101. The
arrangement is such that the line sensor 13101 and the
original make movement relative to each other in the
direction perpendicular to the direction of the scan by the
line sensor 13101, whereby the image signal of the entire
area of the original is obtained. The analog image signals
are converted into digital signals by the A/D converter
13102, and the shading correction circuit 13103 performs
correction of any unevenness of light quantity and
sensitivity occurring in the direction of the scanning of
the line sensor 13101.
The signals after the correction, representing the
level of intensity of light, are delivered to the density
conversion circuit 13104 so as to be changed into signals
representing the levels of density of image. The signals
are further converted by the masking/UCR circuit 13105 into
signals of cyan (C) , magenta (M) , yellow (Y) and black (Bk)
colors which are the output print colors, with correction
2 ~ of color tastes and removal of undercolor.
Then, the signals are delivered to the gamma
correction circuit 13106 which conducts correction of any
output non-linearity and are converted into binary data
through a quasi-halftone processing performed by the binary
2 S circuit 13107. In this embodiment, binary processing is
conducted by using known error diffusion method.
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Among the biarized image signals, the signals C, M and
Bk are delivered to the ink head driving circuit 13108
which drives ink heads 13109 in accordance with these
signals so that the ink heads 13109 jets inks onto a
S recording paper (not shown), whereby an output image is
formed.
Meanwhile, the yellow signal (Y) is led from the
binarizing circuit 13107 to a pattern detection/correction
circuit 13110 which, when there is a specific dot pattern,
replaces such a dot pattern with another pattern. The
yellow binary signal after the removal of the specific dot
pattern is delivered to a pattern adding circuit 13111
which adds an identification information which is peculiar
to the apparatus and which is formed by the removed dot
pattern. The thus modified yellow signal is then delivered
to the ink head driving circuit 13110, whereby a yellow
modified image is formed.
A pattern generating circuit 13112 stores
identification information peculiar to the apparatus, e.g.,
2 0 the name of the model of the machine and the production
serial number of the machine, and operates to encode such
identification information by using the dot pattern removed
by the dot pattern detection/correction circuit 13110. The
thus encoded information is successively output from the
2 $ circuit 13112.
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In this thirteenth embodiment, the circuit denoted by
10801 is constructed by a single semiconductor chip (ASIC
chip). This semiconductor chips 10801 receives and outputs
signals as shown in Fig. 62.
A description will now be given of the dot pattern
detection/correction circuit 13111.
Fig. 63 is a block diagram of the dot pattern
detection/correction circuit 13111 used in the thirteenth
embodiment. As will be seen from this Figure, the dot
pattern detection/correction circuit 13111 has a first-in
first-out memories (FIFO) 13201a, 13201b, D flip-flops
13202a to 13202f, gate circuits 13203a to 13203d, NOR gate
13204 and an AND gate 13205.
The operation of this circuit is as follows.
Figs. 64A, 64B, 64C and 64D show examples of binary
pattern which is used for encoding in the thirteenth
embodiment.
The input yellow binary signal is line-delayed by the
FIFOs 13201a and 13201b so that data corresponding to three
2 0 lines is obtained. The three-line data is then subjected
to a delaying operation conducted by the D flip-flops
13202a to 13202f so that the successive line data is
delayed on pixel basis, whereby an image signal composed of
9 (3 x 3) pixels is obtained. The nine output signals from
2 5 the FIFOs and the flip-flops are delivered to the gate
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circuits 13202a to 13203d which determine whether the
output data corresponds to the predetermined dot pattern.
When the output data conforms with the predetermined
dot pattern, the output of the corresponding gate circuit
is changed to "1", so that the output of the NOR circuit is
changed to "0". Consequently, the output of the AND gate
13205 is masked, so that the central pixel of the pixel
blocks composed of 3 x 3 pixels is changed into "0", i.e.,
changed into white dot.
Each of the gate circuits 13202a to 13202d is a
circuit which produces an output "1" upon receipt of a dot
pattern such as that shown any one of Figs. 64A, 64B, 64C
and 64D. Thus, the dot pattern detection/correction
circuit 13110 performs an operation for changing the black
dot of the central pixel into white dot, when a dot pattern
shown in any one of Figs. 64A, 64B, 64C and 64D is
received.
Fig. 65 is a block diagram showing the construction of
the pattern generating circuit 13112 used in the thirteenth
2 0 embodiment. As will be seen from Fig. 65, this circuit
13112 is composed of a main scan counter 13401, a sub-scan
counter 13402, a specific information LUT 13403 storing
specific information, and a dot pattern LUT for converting
the specific information into a dot pattern. The main scan
2 5 counter 13401 and the sub-scan counter 13402 perform
counting operations in accordance with the clock signals of
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the main and sub-scan directions, so as to enable a
reference to the specific information LUT according to the
position on the image. The specific information LUT 13403
stores the serial No. of the full-color copying machine, so
that the serial No. can be output repeatedly.
In the full-color copying machine of this embodiment,
image signals forming a dot pattern indicating the machine
identification information is generated by making reference
to the dot pattern LUT 13404 on the basis of the serial No.
The dot pattern stored in the dot pattern LUT 13404 is the
pattern as shown in one of Figs. 64A, 64B, 64C and 64 D,
which pattern being subjected to a correction performed by
the pattern detection/correction circuit 13110.
The output from the pattern generating circuit 13112
is supplied to the pattern adding circuit 13111 which
superposes this pattern output on the ordinary image
signals, whereby a copy image is formed from the image
signals with the pattern added thereto. The output image
thus obtained has the identification information in the
2 0 form of a predetermined dot pattern added to the yellow
image data. It is possible to extract the added
information by reading the output copy image by a specific
reader or by enlarging the image and separating the yellow
component. Thus, when thee is no identification
2 5 information added to the image data, the dot pattern which
is to be used for the addition of the information has been
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completely removed in the pattern detection/correction
circuit 13110. Therefore, when a predetermined dot pattern
is detected from the image, such dot pattern can be
determined as being identification information.
S As will be understood from the foregoing description,
in the thirteenth embodiment of the present invention, a
specific dot pattern used for coding of identification
information is removed from the binarized image data, and
the predetermined identification information is added by
using the removed dot pattern, whereby the identification
information is output in a form which is not noticeable to
human eyes and which can easily be detected by specific
detecting means. It is quite difficult to modify this
copying machine in such a manner as to disable only the
function for adding the identification information.
The present invention may be applied to a system
composed of a plurality of apparatuses and also to a single
apparatus. Needless to say, the present invention can ba
achieved by supplying programs to the system or the
2 0 apparatus. The image output function used in the invention
may be an ink jet printer, a thermal transfer printer or
the like, although a laser beam printer has been
specifically mentioned. It is also possible to use, as the
image output means, a bubble jet printer which uses a head
2 S capable of jetting liquid droplets by the force generated
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as a result of film boiling caused by the supply of heat
energy.
It is also to be noted that the output device used in
the invention may be of dot-sequential type, although a
frame-sequential type device has been specifically
described with reference to Fig. 66.
Furthermore, the present invention can employ, as the
input device, various types of information input devices
such as a host computer, a video camera, a still video
camera, a color film reader or the like, as well as the
described image scanner which scans an original by a CCD
scanner. Furthermore, the input data may be image data
which has been formed by a computer graphics technique.
Although in the foregoing description yellow color is
used for printing the added pattern data, the invention
does not exclude the use of various other colors such as
yellowish green, gray or the like color which is not so
noticeable, as well as colors having high luminosity, such
as light purple or light green.
2 0 The present invention is not limited to the above
embodiments and various changes and modifications can be
made within the spirit and scope of the present invention.
Therefore, to apprise the public of the scope of the
present invention the following claims are made.