JP2000287090A - Image processor - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a copy image that is easy to see and attractive image, by determining whether or not a color area density is to be decided, on the basis of a revised threshold according to a total area quantity of color recording data in image data representing the density of the color area. SOLUTION: An image quality 2 key designates a color density correction propriety mode according to a 'total area quantity'. A CPU allows a color counter 340 of an image processing circuit 300 to count number of pixels of each of color recording image data Y, M, C whose level is a standard recording level or higher, selects an 'image quality correction ON' mode when the count exceeds a setting value or selects an 'image quality correction OFF' mode, when the count is less than the setting value. Then the image processor re-scans an original, and the image processing circuit 300 applies image processing to the color recording image data on the basis of read image data R, G, B at that time to generate color recording image data, an image output device receives the data and prints out an image.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an image processing apparatus for digitally processing a visible color image and converting it into color image data for recording, for example, a digital copying machine, an image capturing device (scanner), and a computer. Used for image processing or facsimile.

[0002]

2. Description of the Related Art In general color image processing, most typically, color component information (R, G, B) obtained by reading an image of a color original by a color scanner is represented by:
This is converted into recording color density information (C, M, Y, BK) for the printer. During this conversion, the black component BK is usually colored first.
The recording color components C, M, and Y extracted from the component information and from which the black component BK has been removed are calculated or extracted. In a printer, since the number of recording gradations per dot is small, the recording density gradation is represented by how many recording dots fill the area in units of several dots, for example, an 8 × 8 dot area. In order to determine whether each dot is recorded (data "1") or non-recorded (data "0"), the multi-valued recording color data (C, M, Y, BK) is Binarization is performed using a multi-valued threshold (for example, dither processing). When recording each color in binary, the threshold value is a single value.

By the way, the black component BK is different from the other color components C,
M and Y have a higher contrast in recording and are relatively darker in the printout image, but the color components C, M and Y, especially Y and M, are lighter and have a lower density Y. , M appear much lighter than the density value represented by the data.

Japanese Unexamined Patent Publication No. 5-292306 discloses that, in order to increase the contrast of characters (line drawings) and faithfully reproduce colors, the maximum of the black component BK is first determined from the input color component information R, G, B. The value Kmax is calculated, and it is determined whether the currently focused color part of the input image is a character (line drawing) area or a picture area, and an adjustment coefficient α (α ≦ 1) is determined according to the determination result. (A line drawing) is set to a large value, and to a picture (for example, light green of skin or grass) is set to a small value, and α is multiplied by Kmax to α · Kmax, and the density of the output recording color BK is set. A color image data processing is disclosed.

[0005]

By the way, recording color data
For example, in a printer that records an image in accordance with C, M, Y, and BK, if the image is continuously developed in the rotation direction of the developing unit (sub-scanning direction of the document) due to a mechanical mechanism and physical characteristics, the image is developed The supply amount of the agent or the like cannot keep up, and as a result, the density of the visible image may decrease.

For example, when the user presses the "dark" key of the black density adjustment key on the operation display board in order to increase the density of all the images in response to such a decrease in the density, the image processing is performed. The luminance signal from the image reading device is converted to a large value by the gamma conversion. Conversely, in the case of “thin” adjustment, the luminance signal becomes small. Since the color threshold value is constant, the level balance between black and red before black density adjustment is lost, so that the contrast changes. If the user increases the color density setting to emphasize the color, the color threshold value decreases, the number of pixels where “brightness signal> threshold” holds increases, and the color on the image becomes darker, and The higher the threshold, the lighter the color. In the standard state, the input / output characteristics are almost linear,
If the threshold value is assigned by equally dividing the entire density area, the image will also change linearly visually, but in the case of "dark" or "light", the conversion is performed with an exponential curve However, in this state, the visual change is biased, and it is difficult for the user to adjust the density.

According to the present invention, image processing is performed on read image data to control color image data having low contrast.
The first is to provide easy-to-see and good-looking copy images.
The second object is to perform this control automatically.

[0008]

(1) The present invention relates to an image reading means (101) for reading an image on a document into digital data values in at least two colors, and read image data (R, G, B) is black or non-black, that is, a color, and a color identification means (204) for determining whether the read image data (R, G,
B) or the color image data (C, M, Y) obtained by converting it into a recording color is compared with a threshold value (350) to determine the density of the color area (FIG. 8).
Data processing means (300), means for changing the threshold value in order to cope with image deterioration due to color recording density reduction in the image printing means (400), and a color area determined by the data processing means (300). Image printing means (400) for printing an image of density on recording paper, and an image processing apparatus comprising:
The change unit changes the image data based on the total area (accumulated value) of the color recording data ("1") in the image data (binary C, M, Y) representing the density of the color region. It is characterized in that it is determined whether or not to determine the color area density based on a threshold (FIG. 9). In addition,
In order to facilitate understanding, reference numerals or corresponding items of corresponding elements of the embodiment shown in the drawings and described below are added for reference in parentheses.

According to this, due to the mechanical mechanism and the physical characteristics, when the developing unit is continuously developed in the rotating direction of the developing unit (sub-scanning direction of the original), the supply amount of the developer or the like cannot keep up,
As a result, the color density of the color recording data
The determination is made based on the total area (accumulated value) of (“1”). Thus, when it is determined that the density decreases, the image printing means
By turning ON the determination of the color area density based on the threshold value changed in response to the image deterioration due to the reduction in the color recording density in (400), a color image in which the image deterioration has been compensated can be obtained.

[0010]

(2) Further, the color area density is determined by the threshold value changed by the changing means based on the continuous amount of color recording data in the image data representing the density of the color area. And means for the user to select which of the total area amount and the continuous amount to determine.

When the user selects to determine based on the total area, the image processing apparatus determines the above (1) based on the total area (accumulated value) of the color recording data (“1”). Do. When the user selects to determine based on the continuous amount, the image processing apparatus sets the image data representing the density of the color area.
The color area density is determined based on the threshold value changed by the changing unit based on the continuous amount of the color recording data in the data. That is, due to the mechanical mechanism and physical characteristics, when the developing unit is continuously developed in the rotating direction of the developing unit (sub-scanning direction of the original), the supply amount of the developer or the like cannot keep up, and as a result, the density of the visible image Is determined based on the continuous amount of the color print data ("1"). Also in this case, a color image in which image deterioration is compensated is obtained. Recognition of image degradation is also affected by individual differences and environmental differences. According to the present embodiment, the user can set the criterion for determining whether or not image degradation occurs in the image processing apparatus to one that suits his or her own recognition. (3) Image reading means (101) for reading an image on a document into digital data values in at least two colors, and whether the read image data (R, G, B) is black or other than black, that is, color. , And the read image data (R, G, B) of the color area or the color image data (C, M, Y) obtained by converting the read image data into the recording color (C). 350) to determine the density of the color area (FIG. 8), and the data processing means (300), and the threshold value is changed in order to cope with image deterioration due to a decrease in color recording density in the image printing means (400). And an image printing unit (400) for printing an image of the density of the color region determined by the data processing unit (300) on recording paper. Image data (2
Value C, M, Y), based on the continuous amount of the color recording data (`` 1 '') in the color recording data (`` 1 ''), determines whether or not to determine the color area density based on the threshold value changed by the changing means. (FIG. 10).

Due to the mechanical mechanism and physical characteristics, if the developing unit is continuously developed in the rotation direction (sub-scanning direction of the original), the supply amount of the developer or the like cannot keep up, and as a result, the visible image The case where the density decreases is determined based on the continuous amount of the color print data ("1"). Therefore, when it is determined that the density is reduced, the determination of the color area density based on the threshold value changed to correspond to the image degradation due to the reduced color recording density in the image printing unit (400) is turned on, so that the image degradation is reduced. Is obtained. (4) Input means (602) for setting the changed threshold value
Was further provided. The set threshold value is stored and held in the NVRAM (704), and when the determination of the color region density based on the changed threshold value is turned ON, the color region density is determined by the threshold value of the NVRAM (704). According to this, the user can set the recording density characteristics of the color image based on the changed threshold value. (5) A program for performing the above (1) and (3) is provided, and an input means (602) is provided for a user to specify which of them is to be executed. Recognition of image degradation is also affected by individual differences and environmental differences. According to this embodiment,
The user can set the criterion for judging whether or not the image processing apparatus causes image degradation to one that suits his / her own recognition. (6) image reading means (101) for reading an image on a document into digital data values in at least two colors (R, G, B);
Data processing means (300) for digitally processing the read image data, and data processed image data (C, M, Y, BK)
Image printing means (400) for printing on a recording paper, the image data read by the reading means (101) (R, G,
B) is provided with a color identification means (204) for judging whether black is a color other than black, that is, a color, and a luminance signal (BK) representing the density of the entire image data and a color signal (C , M, Y), determine the density of the color image data by comparing the luminance signal of the area where the color signal is valid with the threshold value (350) (FIG. 8), and in the image printing means (400). In an image processing apparatus that performs visual density correction of a color image by changing the threshold value so as to cope with image deterioration due to a decrease in color recording density and independently controlling the density of the color image, The color image density control is determined by the total area of the color data (see FIG.
9) Alternatively, the color image density control is determined by the continuous amount of color data in the image data (FIG. 10).

Other objects and features of the present invention will become apparent from the following description of embodiments with reference to the drawings.

[0014]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The elements constituting one embodiment of the present invention are shown in FIGS. FIG. 1 shows an image reading apparatus 101, which comprises a reflecting mirror 102, a light source 103, a first mirror 104, and a first scanner that moves at a constant speed, and a second mirror 105 and a third mirror 106. A second scanner, which is equipped and moves following the first scanner at half the speed of the first scanner, optically scans the original A on the contact glass 107 and reflects the reflected image on the lens 1.
08, the image is formed on the one-dimensional solid-state imaging device 109, and read. In general, a CCD is used as the solid-state imaging device 109.

FIG. 2 shows the configuration of the image reading apparatus 101. An analog signal read by the one-dimensional solid-state imaging device 109 is amplified by an amplifier circuit 201 and then converted into a digital signal, that is, read image data R, G, and B by an A / D conversion circuit 202. In this way, the sensitivity unevenness of the solid-state imaging device 109, the light amount unevenness of the light source 103, and the light amount distribution of the lens 108 are corrected.
The solid-state imaging device 109 includes a color identification unit, reads the three primary colors R, G, and B for each color, and outputs black BK and color (other than black) image data R, G, and B by the separation circuit 204. The separation circuit 204 determines from the luminance data R, G, B, and BK whether a black area (including a white area; white is black luminance data 0 and a color signal is invalid) or a color area. Then, multi-gradation (multi-valued) luminance data R, G, B, and BK and a 1-bit color signal indicating whether or not the image is in a color area (black area) are sent to the image processing circuit 300 in the subsequent stage.

FIG. 3 shows the configuration of the image processing circuit 300. The image processing circuit 300 includes a filter correction block 3
10, a scaling block 320, a gradation processing block 330,
There are processes such as a pixel count block 340, a color threshold control 350, and the like.
Sent to 00.

In the case of matrix processing of, for example, 5.times.5 pixels, the filter correction block 310 generates a 4-line delayed image from the input image using a line memory, and inputs 5-line image data to the delayed matrix block. . Each pixel of interest in the matrix block is multiplied by some predetermined fixed value and added to enhance and correct the image data. This operates on the luminance data.

In the scaling step 320, interpolation and thinning-out scaling are performed on the luminance data and the color signal in the main scanning direction only in the scaling step 320, and the image reading means 101 in the sub-scanning direction. Magnification processing is performed by changing the scanner moving speed.

The gradation processing block 330 has a function of converting the luminance data read by the image reading means 101 into recording color image data Y, M, C, and BK, and the output characteristics of the image output device 400 at the subsequent stage. It has a function of γ correction for performing data correction density conversion to obtain matching, and a function of dither processing for smoothing gradation of an image of halftone density.
Since the converted data of the γ correction is nonlinear, the ROM / R
A look-up table conversion method using AM is used.
This performs processing on the recording color image data Y, M, C, and BK.

The pixel count block 340 determines how many recording pixels are present (color area calculation) during a period when the color signal is valid (color area) or how many consecutive recording pixels are present (color continuation amount). Has the function of counting data and retaining data. When the recording color image data Y, M, C, and BK are converted into binary data by performing gradation processing, the color area calculation is based on the binary values during the period when the color signal is valid (color area). The accumulated value and the color continuation amount of the record “1” of data are the number of continuous pixels of the record “1”. Multi-valued recording color image data Y, M, C,
In the case of BK, the color area calculation is based on the integrated value of the values represented by the recorded color image data during the period when the color signal is valid (color area), and the color continuation amount is equal to or larger than the threshold value for determining that there is color. This is the number of continuous pixels of the recording color image data.

The color threshold value control 350 has a threshold value for binarizing the multi-valued recorded color image data Y, M, and C. When the color signal is valid (color area), the multi-valued color control is performed. Recording color image data Y,
If M and C are binarized and each of the multi-valued image data Y, M, and C is a value larger than each threshold value, the recording "1"
It is converted into value image data Y, M, C. When the color signal is invalid (black area), multi-value black image data BK is output.

FIG. 4 shows the configuration of the image output device 400. The image data R transferred from the image reading device 101,
G and B are subjected to image processing by the image processing means 300 and converted into recording color image data Y, M, C, and BK. It is written on the photoconductor 402. As a method of modulating the digital data of the image received from the image processing means 300 into laser light, there are generally power modulation, pulse width modulation, or a combination thereof, and the formation state of the laser light increases as the data value increases. This is a control method that is becoming increasingly common.

FIG. 5 shows the optical writer 401. Laser light emitted from the semiconductor laser 550 is converted into a parallel light beam by the collimator lens 551, and shaped into a light beam of a fixed shape by the aperture 552. The shaped laser light enters the polygon mirror 554 in a form compressed by the first cylinder lens 553 in the sub-scanning direction. The polygon mirror 554 has an accurate polygon and is rotated by a polygon motor 558 in a certain direction at a certain speed. The reflected laser light of the polygon mirror 554 is deflected by the rotation of the mirror 554, and the fθ lenses 555a, 555b, 555
c. fθ lenses 555a, 555b, 5
Reference numeral 55c converts the scanning light having a constant angular velocity so as to scan the photosensitive member 402 at a constant speed, forms an image on the photosensitive member 402 so as to have a minimum light spot, and further has a surface tilt correction mechanism. f
The laser light that has passed through the θ lenses 555a, 555b, and 555c is guided to a synchronization detection sensor 557 by a synchronization detection mirror 556 outside the image area, and after a predetermined time elapses from a synchronization signal for generating a heading signal in the main scanning direction, is output. Is output for one line, and thereafter, this is repeated to form one image.

Referring back to FIG. Since the photoconductor 402 is uniformly charged in advance by the charging charger 403, an electrostatic latent image is formed by the above scanning, and the developing unit 40
4 is visualized. This visible image is the transfer charger 4
05 on the transfer paper, the separation charger 4
At 06, the transfer paper is separated from the photoconductor 402. The separated transfer paper passes through a fixing unit 407 and is pressed and thermally fixed and discharged.

When the developing unit is continuously developed in the rotation direction of the developing unit (sub-scanning direction of the original) due to the mechanical mechanism and physical characteristics, the supply amount of the developer or the like cannot keep up, and as a result, the density of the visible image May decrease.

FIG. 6 shows the operation display board 600. The operation display board 600 includes a display panel 601 indicating the state of the image forming apparatus, and a mode setting section 602 for arbitrarily selecting a mode setting when a user makes a copy. When making a copy, the user sets the density with the UP key and Down key and sets the magnification with the reduction, equal magnification, and enlargement keys. When the start key 603 is pressed, a copy is made. Color designation key
When the UP key and Down key are operated without operating Y, M, C, and BK, the UP and Down instructions due to this are determined assuming that the same instruction is provided for each color Y, M, C, and BK. The recording density indication value is increased or decreased. 1
One of the color designation keys is operated (these keys are turned on)
When the UP key or Down key is operated in the state of being pressed, only the recording density indication value of the designated color of the color designation key is raised or lowered. The image quality 1 key designates standard density printing using the printing density indication value of each color as a standard value.
The key instructs color density correction necessity determination based on “total area amount”, and the image quality 3 key instructs color density correction necessity determination based on “continuous amount”.

The image quality 2 key is turned on (the key is turned on), the color designation key is turned on (the key is turned on), the color is designated, and the density indication value is set with the UP and Down keys. When the color designation key is turned off and the color designation key is turned off, the color designation value at that time is assigned to the NVRAM 704 for the color density correction necessity determination mode based on the “total area amount”. The change instruction value register addressed to the key is written. When the image density 3 key is turned on instead of the image quality 2 key and the above-mentioned density instruction value is changed, the NVRAM 70
4 is written in a change instruction value register addressed to the color designation key for a mode of determining whether color density correction is necessary based on the "continuous amount". Note that the standard density values of each color are also written in the NVRAM 704.

FIG. 7 shows a configuration of a system control device for performing overall control. The system control device includes a CPU 701 that executes an operation program of the image forming apparatus of the present embodiment, a ROM 702 that stores a program, a RAM 703 that temporarily stores data, an NVRAM 704 that holds data even when the power is turned off, and connects them. It comprises an address / data bus 705, a serial communication unit 706 for exchanging signals with external units, an input / output port 707 for exchanging information from operation switches, sensors, display keys, etc. of each section of the image forming apparatus. The copy operation is controlled by changing the operation program in accordance with.

When the user wants to change the density of all the images on the operation display board 600, he turns on the BK designation key and
Pressing the P key increments the black recording density value,
The image data R, G, and B from the image reading device 101 are converted into large values by gamma conversion in the image processing circuit 300. Conversely, when the Down key is pressed, the black recording density value is decremented, and the image data R, G, B are converted to smaller values. Since the thresholds for the colors Y, M, and C are constant, the level balance between black and red before black density adjustment is lost, so that the contrast changes.

A color designation key is provided for the user to emphasize the color.
If the color density setting is increased (darkened) by turning on Y, M, and C, the color recording density value is incremented. Becomes smaller, and each color multi-valued recording color image data Y, M, C>
The number of pixels for which each color threshold is satisfied (pixels for performing color recording) increases, and the colors on the image become darker (the number of recording pixels increases) in area gradation (the number of recording pixels in a region of a predetermined size). When the recording density value is decremented, the color threshold value increases and the recording color decreases.

In the standard state, that is, when the color recording density value is the standard value, the color threshold value is the standard value, the input / output characteristics of the image data are almost linear, and the entire density area is equally divided. If a threshold is assigned, the image will change visually linearly, but in the case of "dark" or "light", the conversion will be performed with an exponential curve, so the visual change However, bias concentration adjustment is difficult. Therefore, the set value of the color threshold value for each color recording density value is not uniformly distributed over the entire area, but when the density value is high, the change value of the color threshold value is changed depending on each case, so that the visual density change is uniform. Thus, the relationship between each color threshold value and each color recording density value (instruction value) is set.

FIG. 8 shows the binarization processing of the multi-valued color recorded image data Y, M, C in the color threshold value control 350. If the color signal is valid (color area), each multi-valued color recorded image data
It is checked whether the data Y, M, and C are larger than the respective color thresholds (steps 1 and 2).
Is output as binary image data Y, M, and C, which indicates non-printing if not large (steps 3 and 3).
4). Here, each color threshold value is a color standard threshold value uniquely corresponding to each color standard density value written in the NVRAM 704 when both the image quality 2 and 3 keys are off.

Image quality 2 key is on and "image quality correction ON"
In this case, each color uniquely corresponding to each color density instruction value written in the change instruction value register of the NVRAM 704 for the color density correction necessity determination mode for the "total area amount" necessity determination mode. When the image quality 3 key is on and “image quality correction is ON”, the threshold value of the NVRAM 704 is
Each color threshold value uniquely corresponding to each color density instruction value written in the change instruction value register addressed to the color designation key for the color density correction necessity determination mode based on “continuous amount”. Even when the image quality key is ON, when "image quality correction is OFF", each color standard threshold uniquely corresponds to each color standard density value written in the NVRAM 704.

FIG. 9 shows image quality correction control of the microprocessor (CPU) 701 when the image quality 2 key is on. When the image quality 2 key is turned on, the color density correction necessity determination mode based on the “total area amount” is designated, so that the CPU 701 determines the color-recorded image data Y, M, and C during the pre-scanning of the original.
The number of pixels equal to or higher than the standard recording level of
The color count 340 is set to "image quality correction ON" when the count value exceeds the set value, and "image quality correction OFF" when the count value is equal to or less than the set value (step 2).
1-24). Then, in "image processing" (step 25), the original is scanned again, and the image processing circuit 300 performs the color recording image data processing shown in FIG. 8 based on the read image data R, G, and B at that time. Is performed to generate color record image data, which is supplied to the image output device 400 to print out the image.

When the image quality 3 key is on, the microprocessor (CPU) 701 executes the image quality correction control shown in FIG. When the image quality 3 key is turned on, the color density correction necessity determination mode based on the “continuous amount” is designated.
Means that the number of continuous pixels of the color recording image data Y, M, and C equal to or higher than the standard recording level is counted by the color count 340 of the image processing circuit 300, and when the count value exceeds the set value, "image quality correction" is performed. ON ”, and when the count value is equal to or smaller than the set value,“ image quality correction OFF ”(steps 31 to 34),
In "image processing" (step 35), the image processing circuit 30
0 performs the color recording image data processing shown in FIG. 8 to generate the color recording image data, and supplies it to the image output device 400 to print out the image.

The setting values of step 22 in FIG.
The set value of the step 32 of 0 indicates the lower limit (threshold value) of the total amount of color image data in the document and the lower limit of the color image data in the document, which are considered to have reduced developing ability due to mechanical mechanism and physical characteristics. The lower limit of the continuous amount (threshold)
In FIG. 9 and FIG. 10, the determination of “image quality correction ON” means that it is determined that the developing capability is reduced due to a mechanical mechanism and physical characteristics. When "image quality correction ON" is set, the user has previously
At each color threshold value uniquely corresponding to each color density instruction value (change value) registered in the change instruction value register of M704, each color recording image data Y, M, and C as shown in FIG. It is binarized. In this case, each color density indication value (change value) is a value larger than the standard value, and since each color threshold value is lower than the standard value, each color binary recording image data for instructing high density recording. Y, M, and C are the image output devices 400
Given to.

The present embodiment is merely an example, and the present embodiment may be implemented with a different configuration, means, and control.

As described above, whether the color recording exceeds the color expression capability of the image forming function in the image output device 400 is determined based on the absolute amount (total area amount) of the color image for one document or the continuous development amount (continuous amount). ), The image density of the same copied image can be kept pseudo-constant. Recognition of image deterioration is affected by individual differences and environmental differences, but the user can select which judgment mode to use.
A judgment mode in which an output deemed appropriate by the user can be obtained.

[Brief description of the drawings]

FIG. 1 is a block diagram illustrating an outline of a mechanism of an image reading apparatus 101 which is an element of an image processing apparatus according to an embodiment of the present invention.

FIG. 2 is a block diagram showing an electric system of the image reading apparatus 101 shown in FIG.

FIG. 3 is a block diagram showing a configuration of an image processing circuit 300 that converts image data read by the image reading apparatus 101 into color recording image data.

FIG. 4 is a block diagram showing an outline of a mechanism of an image output device which prints out color recording image data on paper of the image processing circuit 300;

FIG. 5 is a block diagram showing an outline of a mechanism of an optical writer 401 shown in FIG. 4;

FIG. 6 is an operation display board 6 connected to a system control device 700 which is an element of an image processing apparatus according to an embodiment of the present invention.
00 is a plan view of FIG.

FIG. 7 is a block diagram illustrating an outline of a system control device 700 which is an element of the image processing apparatus according to an embodiment of the present invention.

FIG. 8 is a flowchart showing a process of binarizing each color multi-valued recorded image data Y, M, C of the color threshold value control 350 of the image processing circuit 300 shown in FIG.

FIG. 9 illustrates a microprocessor 701 illustrated in FIG.
This is a flowchart showing the determination processing in the color density correction necessity determination mode based on the “total area amount”.

FIG. 10 illustrates a microprocessor 701 illustrated in FIG.
This is a flowchart showing a determination process in a color density correction necessity determination mode based on “continuous amount”.

[Explanation of symbols]

101: Image reading device 102: Reflecting mirror 103: Light source 104: First mirror 105: Second mirror 106: Third mirror 107: Contact glass 108: Lens 109: Solid-state imaging device 201: Amplifier circuit 202: A / D conversion circuit 203: Shading correction circuit 204: Separation circuit 300: Image processing circuit 400: Image output device 401: Optical writer 402: Photoconductor 403: Charger
Ja 404: Developing unit 405: Transfer char
Jar 406: Separation charger 407: Fixing device 550: Semiconductor laser 551: Collimating lens 552: Aperture 553: First cylinder lens 554: Polygon mirror 555a-c: fθ
Lens 556: Sync detection mirror 557: Sync detection sensor 600: Operation display board 601: Display panel 602: Mode setting section 603: Start key

──────────────────────────────────────────────────の Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI Theme coat ゛ (Reference) G06T 5/00 G06F 15/68 320A H04N 1/52 H04N 1/46 BF Term (Reference) 2C262 AA05 AA17 AA26 AA27 AB05 AC02 AC04 BA02 BA09 BB36 EA13 2H030 AD07 AD12 BB02 BB63 5B057 BA25 BA26 BA30 CA01 CA08 CA12 CA16 CB01 CB07 CB12 CB16 CC01 CE14 CH18 CH20 DB02 DB06 DB08 DC04 DC25 DC30 5C077 LL16 LL19 MP08 PP27 PP28 PP28 PP28 PP28 PP28 PP28 PP28 PP08 SS05 5C079 HB03 LA03 LA10 LA12 LA34 LC01 NA06 NA18 PA01 PA02

Claims (3)

[Claims] An image reading means for reading an image on a document into a digital data value in at least two colors, and a color identification means for determining whether the read image data is black or non-black, that is, a color. Data processing means for determining the density of the color area by comparing the read image data of the color area or the color image data obtained by converting the read image data into the recording color with a threshold value; An image processing apparatus comprising: means for changing the threshold value in response to deterioration; and image printing means for printing an image having a density of a color region determined by the data processing means on recording paper. Means for determining whether or not to determine the color area density based on the threshold value changed by the changing means based on the total area of the color recording data in the image data representing the density of the area. When Image processing device. 2. An image data representing the density of the color area.
Means for determining whether or not to determine the color region density based on the threshold value changed by the changing means based on the continuous amount of color recording data in the data, and determining based on either the total area amount or the continuous amount. 2. The image processing apparatus according to claim 1, further comprising: means for allowing a user to select one of the following. 3. Image reading means for reading an image on a document into digital data values of at least two colors or more, and color identification means for judging whether the read image data is black or other than black, that is, a color. Data processing means for determining the density of the color area by comparing the read image data of the color area or the color image data obtained by converting the read image data into the recording color with a threshold value; An image processing apparatus comprising: means for changing the threshold value in response to deterioration; and image printing means for printing an image having a density of a color region determined by the data processing means on recording paper. Means for determining whether to determine the color area density based on the threshold value changed by the changing means based on the continuous amount of color recording data in the image data representing the density of the area. You Image processing device.