U.S. patent application number 13/008119 was filed with the patent office on 2011-05-12 for image processing method.
This patent application is currently assigned to KABUSHIKI KAISHA TOSHIBA. Invention is credited to Haruko Kawakami.
Application Number | 20110110556 13/008119 |
Document ID | / |
Family ID | 38873611 |
Filed Date | 2011-05-12 |
United States Patent
Application |
20110110556 |
Kind Code |
A1 |
Kawakami; Haruko |
May 12, 2011 |
IMAGE PROCESSING METHOD
Abstract
The main CPU executes Fourier transform to the partial image,
then performs strict spectrum analysis 1 for judging the
presence/absence of data at a coordinate position designated in
advance on a Fourier transform plane with high resolution for
judging the presence/absence of prohibition of duplication, then
judges whether duplication-prohibited data exists or not, and
clears both the partial image and the document image if it is
judged that duplication-prohibited data exists. If it is judged
that duplication-prohibited data does not exist, the main CPU
executes spectrum analysis 2 for broadly inspecting the existence
of a periodic component instead of lowering the resolution from the
spectrum analysis 1 and judges whether a structure other than DC
component exists or not. If the existence of a minute quantity of
change that could not exist in a normal image is recognized, the
main CPU performs partial image processing such as amplifying the
quantity of change, then superimposes it onto the document image,
and supplies the image on which the superimposing processing has
been executed, to an output unit and a liquid crystal display unit,
thus outputting or displaying the image.
Inventors: |
Kawakami; Haruko;
(Mishima-shi, JP) |
Assignee: |
KABUSHIKI KAISHA TOSHIBA
Tokyo
JP
TOSHIBA TEC KABUSHIKI KAISHA
Tokyo
JP
|
Family ID: |
38873611 |
Appl. No.: |
13/008119 |
Filed: |
January 18, 2011 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
|
|
11474185 |
Jun 23, 2006 |
7894624 |
|
|
13008119 |
|
|
|
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Current U.S.
Class: |
382/100 |
Current CPC
Class: |
H04N 1/3216 20130101;
G06T 2201/0051 20130101; H04N 1/32144 20130101; H04N 1/00846
20130101; G06T 1/0021 20130101; G06T 2201/0064 20130101; G06T
2201/0052 20130101 |
Class at
Publication: |
382/100 |
International
Class: |
G06K 9/00 20060101
G06K009/00 |
Claims
1. An image processing method for an image processing apparatus
configured to perform predetermined processing to document image
data and supply the processed document image data to an output unit
or a storage unit, comprising: judging the existence of at least
one embedded data when performing processing to superimpose partial
image data sliced out from a predetermined document data and the
document image data, and if the existence of data indicating
prohibition of duplication of the partial image data sliced out
from the predetermined document data is recognized by this
judgment, issuing a warning to the effect that the superimposition
of the partial image data sliced out from the predetermined
document data is prohibited, thus stopping the superimposing
processing.
2. An image processing method for an image processing apparatus
configured to perform predetermined processing to document image
data and supply the processed document image data to an output unit
or a storage unit, comprising: judging the existence of at least
one embedded data when performing processing to superimpose partial
image data sliced out from a predetermined document data and the
document image data, and if the existence of data indicating
prohibition of duplication of the partial image data sliced out
from the predetermined document data is recognized by this
judgment, performing processing to change the partial image data
sliced out from the predetermined document data to an image density
different from its original image and then superimpose the
image.
3. An image processing method for an image processing apparatus
configured to perform predetermined processing to document image
data and supply the processed document image data to an output unit
or a storage unit, comprising: judging the existence of at least
one embedded data when performing processing to superimpose partial
image data sliced out from a predetermined document data and the
document image data, and if the existence of data indicating
prohibition of duplication of the partial image data sliced out
from the predetermined document data is recognized by this
judgment, performing processing to reproduce in achromatic color a
part that should be reproduced in chromatic color, of the partial
image data sliced out from the predetermined document data.
4. An image processing method for an image processing apparatus
configured to perform predetermined processing to document image
data and supply the processed document image data to an output unit
or a storage unit, comprising: judging the existence of at least
one embedded data when performing processing to superimpose partial
image data sliced out from a predetermined document data and the
document image data, and if the existence of data indicating
prohibition of duplication of the partial image data sliced out
from the predetermined document data is recognized by this
judgment, performing processing to shift the partial image data
sliced out from the predetermined document data to double positions
and then superimpose the image.
Description
CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] This application is a Division of application Ser. No.
11/474,185 filed Jun. 23, 2006, the entire contents of which are
hereby incorporated herein by reference.
BACKGROUND OF THE INVENTION
[0002] 1. Field of the Invention
[0003] This invention relates to an image processing method for an
image processing apparatus that reads an image of a manuscript and
processes the read image of the manuscript.
[0004] 2. Description of the Related Art
[0005] A technique of embedding a watermark or the like in advance
into a document image the duplication of which is not permitted,
and thus prohibiting the duplication of the image itself, or a
technique of embedding data related to the contents of a document
and thus preventing falsification of the data and the contents of
the document of the corresponding part, is becoming generally
popularized.
[0006] However, though a method of embedding information of
copyright owner and prohibition of duplication into a part that
constitutes an entire target image for copyright protection and
thus limiting changes and downloading of a file is employed mainly
with respect to soft copies in network distribution, for an image
that is very likely to be misused after duplication such as a stamp
or sign that is additionally written after making a hard copy, it
is difficult to embed data indicating prohibition of duplication
into the image in advance.
[0007] As described above, stamps and signatures vary in shape and
size, and detection of them is difficult by using a method like
pattern matching. Also, unless a target image is changed to a
predetermined color in printing from a monochrome read image, or
unless an image is recorded after its original image is magnified
at an extremely large or small magnification, an image equivalent
to the target image can be acquired by magnifying again to the size
of the original image. Therefore, compared with other specific
images, duplication and use of them can be easily carried out.
Thus, there is a problem that the possibility of misuse is
high.
BRIEF SUMMARY OF THE INVENTION
[0008] The object of an aspect of the present invention is to
provide an image processing method for an image processing
apparatus that enables detection of an image of a stamp, sign or
the like, in which information cannot be embedded because its
detection is difficult and it is often additionally written later,
and thus enables prevention of misuse after slicing and
duplication.
[0009] According to an aspect of the present invention, there is
provided an image processing method for an image processing
apparatus configured to perform predetermined processing to
document image data and supply the processed document image data to
an output unit or a storage unit, comprising the step of:
performing embedding processing of data expressed by a minute
change in value of a pixel with respect to a preset area, when
expanding the document image data to bit map data.
[0010] Additional objects and advantages of an aspect of the
invention will be set forth in the description which follows, and
in part will be obvious from the description, or may be learned by
practice of the invention. The objects and advantages of an aspect
of the invention may be realized and obtained by means of the
instrumentalities and combinations particularly pointed out
hereinafter.
BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWING
[0011] The accompanying drawings, which are incorporated in and
constitute a part of the specification, illustrate preferred
embodiments of the invention, and together with the general
description given above and the detailed description of the
embodiments given below, serve to explain the principles of an
aspect of the invention.
[0012] FIG. 1 is a block diagram showing a schematic configuration
of a multifunction peripheral having an image processing apparatus
of this invention;
[0013] FIG. 2 is a view for explaining an embedding operation in an
image processing method according to a first embodiment;
[0014] FIG. 3 is a view for explaining the details of embedding to
an image;
[0015] FIG. 4 is a view for explaining an operation at the time of
reading in the image processing method;
[0016] FIG. 5 is a view showing a spectral arrangement on a Fourier
transform plane;
[0017] FIG. 6 is a view for explaining image superimposing
processing according to the first embodiment;
[0018] FIG. 7 is a flowchart for explaining operations of the image
superimposing processing;
[0019] FIG. 8 is a view for explaining image superimposing
processing according to a second embodiment; and
[0020] FIG. 9 is a view for explaining image superimposing
processing according to a third embodiment.
DETAILED DESCRIPTION OF THE INVENTION
[0021] Hereinafter, an embodiment of this invention will be
described with reference to the drawings.
[0022] FIG. 1 shows a schematic configuration of a multi function
peripheral (hereinafter described as MFP) 10 having an image
processing apparatus of this invention.
[0023] As shown in FIG. 1, the MFP 10 includes a main CPU 1, a ROM
2, a RAM 3, an input unit 4, an image processing apparatus 5, a
storage unit 6, an output unit 7, and an operating panel 8. The
foregoing constituent elements are connected via a bus 20 with the
main CPU 1 situated at the center.
[0024] The main CPU 1 is in charge of the overall operations of the
MFP 10 and operates in accordance with programs stored in advance
in the ROM 2.
[0025] The RAM 3 stores image data or various types of
information.
[0026] The input unit 4 optically scans a manuscript and changes
the manuscript to image data.
[0027] The image processing apparatus 5 has a pattern recognizing
unit 11 and a gray level correcting unit 12, and performing various
types of processing to image data. The pattern recognizing unit 11
performs pattern recognition for judging duplication-prohibited
image data or the like. The gray level correcting unit 12 corrects
the gray level of image data.
[0028] The storage unit 6 is formed by a hard disk device or the
like and stores image data or various types of information.
[0029] The output unit 7 prints image data or the like onto a
paper.
[0030] The operating panel 8 has a display that is formed by a
liquid crystal display unit 9 with a built-in touch panel, and
plural hard keys. In this operating panel 8, various operations in
the MFP 10 are carried out by using the plural hard keys and the
liquid crystal display unit 9 with the built-in touch panel.
[0031] Next, the outline of this invention in such a configuration
will be described.
[0032] FIG. 2 illustrates embedding in the image processing method
according to the first embodiment.
[0033] As shown in FIG. 2, first, a document file (template file)
formed by complementing a template or text of a document image
having a duplication-prohibited part by using document processing
software is inputted from the input unit 4 (a). Next, a
duplication-prohibited area (indicated by a dotted line in FIG. 2)
of the template file or document file is designated in advance, and
a minute change that can be hardly visually recognized is made in
the area, thus embedding information indicating prohibition of
duplication from the image processing apparatus 5 (b). The document
image to which the embedding processing has been done is outputted
as a hard copy via the storage unit 6 and the output unit 7, and a
sign or stamp is additionally written in the corresponding part
where the data indicating prohibition of duplication has been
embedded (c, d).
[0034] FIG. 3 shows an exemplary pattern in the case where this
data indicating prohibition of duplication is embedded as a
periodic component. If the voltage of embedded data is plural bits,
data modulation of plural types of periodic components having
difference periods and angles as shown in FIG. 3 is superimposed on
a signal value of the original image, and a signal value d after
superimposing the data on the original signal value d0 is acquired
by the following equation.
d = d 0 + n = 1 b n WAn * cos ( cos ( W .theta. n ) .times. 2 i
.pi. / WLn + sin ( W .theta. n ) .times. 2 j .pi. / WLn )
##EQU00001##
[0035] Here, bn represents the number of bits of data to be
superimposed. WAn represents the amplitude of the periodic
component. W.theta.n represents the angle formed with the main
scanning direction of the period component. WLn represents the
period, and i, j represent a position of a target point in the main
scanning direction and sub scanning direction.
[0036] In this manner, additional writing can be carried out by
making a change representing information of prohibition of
duplication or the like in a target area in advance, and even an
image in which a target partial image has largely varied color and
shape so that detection of this image part is difficult, can be a
subject for prohibition of duplication.
[0037] Regardless of whether duplication is permitted or not, the
additional data may include the date of creation, distribution
range, degree of confidentiality and the like.
[0038] FIG. 4 shows an operation at the time of reading. An image
formed by superimposing a sign or stamp to be a subject for
prohibition of duplication onto an area where data has been
embedded, is read by the input unit 4 (e), and the target image is
taken in as a data file (f). Also a scanner, copy machine or
digital camera may be used.
[0039] In the case of trying to slice out and save the target part
where the data of prohibition of duplication has been embedded, of
the image taken in as a data file, if the image processing
apparatus 5 that executes the slicing of the image can detect the
data embedded in this image area, the main CPU 1 compares the
extracted data with the data stored in the storage unit 6 that is
directly connected with the judgment, and executes judgment on
whether the data, is a subject for prohibition of duplication or
the like.
[0040] In the case where the technique of superimposing plural
periodic components as described above is employed for embedding
here, when Fourier transform is executed, peaks in spectral value
of angle and frequency of the embedded periodic components can be
confirmed on a frequency surface, as shown in FIG. 5. This spectral
value of the target angle and frequency is compared with a
predetermined threshold value and then on/off of the bit is judged,
thus detecting the embedded data. If the target part is judged to
be duplication-prohibited in the stage where this data is detected,
the setting is made so that execution of slicing or additional
saving of the sliced part will be stopped. Also, a warning may be
issued that indicates prohibition of duplication.
[0041] If the image processing apparatus 5 cannot be detect the
data, as in the case where it cannot confirm the existence of the
data by comparing with the periodic component stored in the storage
unit 6 in advance other than the original image, the input image is
saved at least without causing degradation of the partial image of
the input image (g), and duplication can be prevented when the
sliced partial image is reused (h).
[0042] FIG. 6 shows a process related to overlay processing in the
case where the slicing or saving of a target part of an image
according to the first embodiment is executed in another image
processing system and then provided. When (k) superimposing a
sliced partial image (i) on another document file (j), if
information of prohibition of duplication is recognized in the
partial image, the superimposed image itself is stopped (l). If
data of prohibition of duplication is not recognized but the
existence of a minute quantity of change which could not exist in a
normal image is recognized, the minute change is emphasized and
then superimposed on a document image that is an overlay target
(m).
[0043] Next, the above-described image processing according to the
first embodiment will be described with reference to the flowchart
of FIG. 7.
[0044] The main CPU 1 first executes Fourier transform to the
partial image (ST1), then performs strict spectrum analysis 1 for
judging the presence/absence of data at a coordinate position
designated in advance on a Fourier transform plane with high
resolution for judging the presence/absence of prohibition of
duplication (ST2), and judges whether duplication-prohibited data
exists or not (ST3). If it is judged that duplication-prohibited
data exists, the main CPU 1 clears both the partial image and the
document image (ST4).
[0045] If it is judged in step ST3 that duplication-prohibited data
does not exist, the main CPU 1 executes spectrum analysis 2 for
broadly inspecting the existence of a periodic component instead of
lowering the resolution from the spectrum analysis 1 (ST4) and
judges whether a structure other than DC component exists or not
(ST5).
[0046] If the existence of a minute quantity of change that could
not exist in a normal image is recognized, the main CPU 1 performs
partial image processing such as amplifying the quantity of change
and then superimposes it onto the document image (ST6, 7). The main
CPU 1 supplies the image on which the superimposing processing has
been executed, to the output unit 7 and the liquid crystal display
unit 9, thus outputting or displaying the image (ST8).
[0047] As described above, according to the first embodiment, in
the case where there is an image that is very likely to be misued
as it is sliced out, duplicated and superimposed on another
document image, the misuse can be prevented by performing the
above-described processing.
[0048] Next, a second embodiment will be described.
[0049] In the above-described first embodiment, if the existence of
data indicating prohibition of duplication is recognized, the
processing is carried out so as not to perform output or display
itself, whereas the main CPU 1 in this second embodiment changes
the partial image into a non-reusable shape by doubly superimposing
the partial image (n) as shown in FIG. 8, or otherwise, and thus
performs control to prevent misuse of the image.
[0050] Next, a third embodiment will be described.
[0051] The main CPU 1 in the third embodiment makes a change such
as erasing a part of color channels from the partial image (s) or
arranging the partial image in one channel of monochrome alone (r)
as shown in FIG. 9, and thus performs control to prevent misuse of
the image.
[0052] As described above, according to the embodiments of the
invention, with the above-described configuration, data indicating
prohibition of duplication is embedded in advance into a part where
a predetermined image is additionally written, in a document image,
thereby enabling superimposition of information even for target
images having various shapes and sizes. Also, even for an image
that has largely varied shape and size and that cannot be dealt
with by an ordinary detecting method, slicing processing can be
prevented. Even for an image that has been sliced out because it
was not found in the detection, the image is detected when it is
superimposed on another document, and a change is made in the
sliced image or its output or display is stopped, thereby enabling
prevention of misuse.
[0053] Moreover, even when it cannot be judged that the image is
duplication-prohibited because the system that embedded the
information is different, a minute change that is different from a
normal document image is detected and the change is emphasized,
thereby enabling prevention of misuse of the sliced image.
[0054] Additional advantages and modifications will readily occur
to those skilled in the art. Therefore, the invention in its
broader aspects is not limited to the specific details and
representative embodiments shown and described herein. Accordingly,
various modifications may be made without departing from the spirit
or scope of the general inventive concept as defined by the
appended claims and their equivalents.
* * * * *