JPH08294012A - Image processing unit and its method - Google Patents

Abstract

PURPOSE: To provide the image processing unit and its method in which a print- out with desired hue and density is easily obtained. CONSTITUTION: Hue information of an output image in the density indicated by a density indicator 12 is displayed on a hue indicator 11 of a display section 218. The operator uses an operation section 13 to instruct a hue of an output image on the basis of the hue information indicated by the hue indicator 11. A CPU sets a processing parameter of an image processing section to obtain the instructed hue.

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 and a method thereof, and more particularly, to an image processing apparatus and a method thereof for subjecting an input image to image processing and outputting.

[0002]

2. Description of the Related Art In a digital color image forming apparatus using an electrophotographic system, a method of adjusting a lower value,
There are many adjustments such as color balance and printer gamma correction.

[0003]

However, the above-mentioned technique has the following problems. In other words, in order to obtain a printout of a desired hue or density, it is necessary to be familiar with the numerous adjustment methods described above and to make those adjustments individually, which poses a problem that the user's skill level is required.

An object of the present invention is to solve the above-mentioned problems, and it is an object of the present invention to provide an image processing apparatus and a method therefor capable of easily obtaining a printout of a desired hue or density.

[0005]

[Means for Solving the Problems] and

The present invention has the following structure as one means for achieving the above object.

An image processing apparatus according to the present invention is an image processing apparatus for performing image processing on an input image and outputting the image, the display means displaying the hue information of the image after the image processing, and the display means. Instruction means for instructing the hue of the image after image processing based on the hue information displayed by, and setting means for setting the processing parameter of the image processing so that the hue instructed by the instructing means is obtained. The display means updates the hue information to be displayed based on the hue instructed by the instructing means.

Further, an image processing apparatus for performing image processing on an input image and outputting the image, the output means outputting the hue information of the image after the image processing, and the hue information output by the output means. Based on the instruction means for instructing the hue of the image after image processing, and setting means for setting the processing parameter of the image processing so as to obtain the hue instructed by the instructing means, the output means The hue information updated based on the hue instructed by the instructing means is output.

Further, input means for inputting image data representing a document image, detecting means for detecting a color distribution of the document image from the image data, display means for displaying the color distribution, and the displayed color. An instruction means for instructing a color distribution after color correction based on the distribution, and a color correction means for setting a color correction parameter based on the instruction of the instructing means to perform color correction on the image data. Characterize.

An image processing method according to the present invention is an image processing method for subjecting an input image to image processing and outputting the image, and a displaying step for displaying hue information of the image after the image processing, and the displaying step. Instructing step for instructing the hue of the image after image processing based on the hue information, and setting step for setting the processing parameter of the image processing so as to obtain the instructed hue, the display step, The displayed hue information is updated based on the instructed hue.

An image processing method for subjecting an input image to image processing and outputting the image, wherein an output step of outputting hue information of the image after the image processing and an image based on the output hue information An instruction step for instructing the hue of the image after processing and a setting step for setting the processing parameter of the image processing so that the instructed hue is obtained are provided, and the output step is based on the instructed hue. It is characterized in that the updated hue information is output.

Further, an input step of inputting image data representing a document image, a detection step of detecting a color distribution of the document image from the image data, a display step of displaying the color distribution, and the displayed color. An instruction step for instructing the color distribution after color correction based on the distribution, and setting color correction parameters based on the instruction of the instructing step,
A color correction step of performing color correction on the image data.

[0012]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An image processing apparatus according to an embodiment of the present invention will be described in detail below with reference to the drawings.

First, the outline of a full-color image forming method will be described.

FIG. 1 is a view showing an example of the arrangement of an image processing apparatus according to an embodiment of the present invention, which is composed of a reader section A and a printer section B.

The original 101 placed on the original table glass 102 of the reader unit A is illuminated by a light source 103. The reflected light from the original 101 is imaged on the CCD sensor 105 via the optical system 104. The CCD sensor 105 uses the red, green, and blue CCD line sensor groups arranged in three rows to generate red, green, and blue color component signals for each line sensor. These reading optical system units scan the document in the direction indicated by the arrow in the figure to convert the document image into an electric signal data string in line units.

Further, the white level of the CCD sensor 105 and the positioning member 107 for preventing the original 101 from being obliquely placed by abutting the sides of the original 101 on the original table glass 102, and the white level of the CCD sensor 105 are determined. A reference white plate 106 for performing shading correction in the thrust (array) direction of 105 is arranged.

The image signal output from the CCD sensor 105 is
After being subjected to image processing by the image processing unit 108, it is input to the printer control unit 109 of the printer unit B.

FIG. 2 is a block diagram showing a configuration example of the image processing unit 108.

In the figure, a CPU 214 controls the entire reader unit A including the following components according to a program stored in advance in a ROM 216 or the like. The RAM 215 is used as a work area by the CPU 214, and the ROM 216 stores image processing parameters and the like in addition to the control program. The operation unit 217 has a display unit 218 such as a keyboard, a touch panel, and an LCD, and transmits an instruction from an operator to the CPU 214, and displays the operating condition and state of the device by the CPU 214.

Further, the address counter 212 counts the clock CLK for each pixel generated by the clock generator 211 and outputs a main scanning address signal representing a pixel address for one line. The decoder 213 decodes the main scanning address signal output from the address counter 212, and shifts the reset pulse or the reset pulse to the CCD sensor 1 for each line.
Signal 219 that drives 05 and 1 output from CCD sensor 105
A signal VE representing an effective area in the line signal, a line synchronization signal HSYNC, etc. are generated. The address counter 212
Is cleared by the signal HSYNC and starts counting the main scanning address of the next line.

The image signal output from the CCD sensor 105 is
After being input to the analog signal processing unit 201 and adjusted for gain and offset, the A / D conversion unit 202, for example,
It is converted into an 8-bit RGB digital image signal, and the shading correction unit 203 performs known shading correction using the signal obtained by reading the reference white plate 106 for each color.

The line delay unit 204 corrects the spatial deviation contained in the image signal output from the shading correction unit 203. This spatial shift is caused by the line sensors of the CCD sensor 105 being arranged at a predetermined distance from each other in the sub-scanning direction. Specifically, with the B color component signal as a reference, the R and G color component signals are line-delayed in the sub-scanning direction to synchronize the phases of the three color component signals.

The input masking unit 205 converts the color space of the image signal output from the line delay unit 204 into the NTSC standard color space by the matrix calculation of equation (1). That is, the color space of each color component signal output from the CCD sensor 105 is determined by the spectral characteristics of the filter for each color component,
This is converted to the standard color space of NTSC. However, Ro, Go, Bo: Output image signal Ri, Gi, Bi: Input image signal

The LOG conversion unit 206 is composed of a look-up table such as a ROM, and the input masking unit 20
The RGB luminance signal output from 5 is converted to a CMY density signal. The line delay memory 207 includes a control signal UCR, FILTER,
LOG converter 20 for the period (line delay) for generating SEN, etc.
The image signal output from 6 is delayed.

The masking / UCR unit 208 extracts the black component signal K from the image signal output from the line delay memory 207, and further performs a matrix calculation for correcting the color turbidity of the recording color material of the printer unit B in the YMCK image. Apply to signal, reader unit
For each reading operation of A, an 8-bit color component image signal is output in the order of M, C, Y, K. The matrix coefficient used for the matrix calculation is set by the CPU 214.

The gamma correction unit 209 performs density correction on the image signal output from the masking / UCR unit 208 in order to match the image signal with the ideal gradation characteristic of the printer unit B.
The output filter (spatial filter processing unit) 210 applies edge enhancement or smoothing processing to the image signal output from the gamma correction unit 209 according to the control signal from the CPU 214.

The MCYK frame-sequential color component image signal processed in this way is sent to the printer section B, and density recording by PWM is performed.

FIG. 3 is an example of a timing chart of each control signal in the image processing unit 108.

In the figure, a signal VSYNC is an image effective section signal in the sub-scanning direction, and image reading (scanning) is performed in the section where the signal is "1", and M, C, Y and K are sequentially read. An image signal is formed. Further, the signal VE is an image effective section signal in the main scanning direction, and the start timing of main scanning (that is, the timing when the signal HSYNC falls from "1" to "0") in the section where the signal is "1". Besides, it is mainly used for line counting control of line delay. Signal CLK
Is a pixel synchronization signal, and the image data is transferred at the timing when the signal rises from “0” to “1”.

Next, the printer section B will be described with reference to FIG.

The image data input from the reader unit A to the printer control unit 109 is converted into a pulse signal according to the image data by a pulse width modulator (PWM) (not shown) and drives the laser light source 110 (not shown). Input to laser driver. The laser light output from the laser light source 110 is
After being scanned in the main scanning direction by the polygon mirror 1, the photosensitive drum 4 uniformly charged by the primary charger 8 is irradiated via the mirror 2 to form an electrostatic latent image on the photosensitive drum 4. To do.

The photosensitive drum 4 is rotating in the direction of the arrow shown in the figure, and the latent images formed on the photosensitive drum 4 are sequentially developed with toner by the developing device 3 for each formed color. In this embodiment, a two-component system is used as a developing system, and developing devices 3 for respective colors are arranged around the photosensitive drum 4 in the order of black K, yellow Y, cyan C, and magenta M from the upstream in the rotation direction. However, under the control of the printer control unit 109, the developing device 3 corresponding to the formed color comes into contact with the photosensitive drum 4 at the timing of developing the latent image formed on the photosensitive drum 4.

On the other hand, the transfer drum 5 around which the recording paper 6 supplied from the recording paper cassette or the like is wound is rotated once for each forming color, and the toner image on the photosensitive drum 4 is transferred onto the recording paper 6. After a total of four rotations, the four color toner images are transferred in an overlapping state.

After the transfer, the recording paper 6 is separated from the transfer drum 5, and the toner image is fixed by the fixing roller pair 7 to complete the printing of a full-color image.

4 and 5 are views showing an example of the image adjustment screen displayed on the display unit 218 at the time of image adjustment.
When a predetermined key (or a predetermined combination of keys) of the operation unit 217 shown in FIG. 7 is pressed, it is displayed by the CPU 214.
Reference numeral 11 denotes a hue display, which is a hue plane 11 'of the output image at a predetermined density. Further, 22 is a density display, which is used to display the density of the hue plane 11 ′ currently displayed on the hue display 11 by the marker 22 ′.

Now, with the image adjustment screen being displayed on the display unit 218, the operator sets the original document 1 on the original platen glass 102.
When 01 is placed and the copy start key 14 of the operation unit 217 is pressed, the original 101 is scanned and the hue plane of the output image of the original and its density are displayed on the display unit 218.

The operator operates the image adjustment unit 13 of the operation unit 217.
By designating an arbitrary position in the density bar 13b of the above with a coordinate input pen or the like, the hue plane at that density is displayed on the hue display 11 (see FIG. 5). Therefore, the hue plane at the density to be adjusted is displayed. By displaying an arbitrary position in the color wheel 13a with the coordinate input pen or the like in the state of being displayed on the hue display unit 11, the hue of the output image at the density can be arbitrarily set. Then, by repeating this hue adjustment at different densities, the hue of the output image can be adjusted over the entire color space.

After the operator finishes adjusting the hue of the output image, the operator presses the copy start key 14 again to scan the original 101, and the image is printed out in the desired hue and density.

The CPU 214 uses, for example, masking / UC
The hue of the output image is obtained from the output of the LOG conversion unit 206 by emulating the image processing performed by the R unit 208, the gamma correction unit 209, the output filter 210, and the like. Alternatively,
Similar to the normal copy operation, the result of performing image processing on the original image read by the masking / UCR unit 208, the gamma correction unit 209, the output filter 210, etc., that is, the output filter 21.
The hue of the output image may be obtained by analyzing the output of 0.

FIG. 6 is a diagram for explaining the hue adjustment. That is, the operator corrects the original hue plane 11a like the hue plane 11b when it is desired to suppress the yellow hue, and narrows it like the hue plane 11c when it is desired to make it overall dull, and also as a whole. If you want to make it vivid, the hue plane 11
You can do the operation to expand like d.

FIG. 8 is a flowchart showing an example of the above-mentioned image adjustment procedure, which is executed by the CPCPU 214 after a predetermined key (or a predetermined combination of keys) for instructing the start of image adjustment is pressed by the operator. .

In step S1, hue display 11 and density display 22 are displayed on the display unit 218, and in step S2 the copy start key
Wait for 14 to be pressed. When the copy start key 14 is pressed, the document 101 on the platen glass 102 is scanned in step S3, and the hue display 11 is updated according to the output image of the document image read in step 4.

Then, in step S5, it is determined whether or not the image adjusting unit 13 is operated. If the image adjusting unit 13 is operated, the process returns to step S4 and the hue display 11 is displayed according to the operation (instruction). Update. If the image adjustment unit 13 is not operated, it is determined in step S6 whether or not the copy start key 14 is pressed, and if not pressed, the process returns to step S5,
If it is pressed, in step S7, the processing parameters such as the masking / UCR unit 208, the gamma correction unit 209, and the output filter 210 are set so that the output image of the designated hue is obtained, and then the copy operation is performed to copy the original. After printing out a copy of 101, the process ends.

It should be noted that the processing parameters set in step S7 are subjected to the default processing by adjusting the hue again by the image adjusting unit 13 or by a predetermined key (or a combination of predetermined keys) of the operation unit 217. It is maintained until it is returned to the parameter.

Further, the CPU 214 may store the adjusted hue, that is, the set processing parameter in a non-volatile memory (not shown) or the like according to an instruction from the operator. In this way, the operator can recall the hue that has been adjusted in the past, if necessary, and the time required for the adjustment can be shortened.

As described above, according to this embodiment, the operator can directly operate (instruct) the hue of the output image over the entire color space in order to obtain the desired hue and density. Therefore, the operator does not need to individually perform a large number of image adjustments such as the change of the lower price, the color balance, and the gamma correction of the printer. Even if the operator is not familiar with these adjustment methods, it is easy to print out the desired hue and density. Can be obtained.

[0047]

[First Modification] The CPU 214 can print out the hue information of the output image obtained by scanning the document as an image of which an example is shown in FIG.

In FIG. 9, the hue planes at four densities are recorded on the recording paper 15, and the operator views this printout and obtains an image of the desired hue and density accordingly. Image adjustment unit 13
To operate. Then, if necessary, in order to confirm the adjusted hue, the printout shown in FIG. 9 is output again, and if the desired hue is obtained, copying is instructed. If the desired hue is not obtained, try again in the image adjustment section.
13 will be operated.

By doing so, even when the display area of the display unit 218 is small and the hue display 11 and the density display 22 cannot be displayed, by printing out the hue information, it is possible to easily perform the same processing as in the above-described embodiment. Image adjustment can be performed.

In the above description, an example in which the density display has four levels is shown in the drawings, but the present embodiment is not limited to this, and it is also possible to have five levels or more or three levels or less. Therefore, if the number of density display steps is reduced, the number of adjustment points is reduced, the operation procedure is simplified, and the processing of the CPU 214 is also reduced. Conversely, if you increase the number of density display steps,
You can adjust the hue more finely, but on the other hand,
The number of adjustment points increases and the operation procedure becomes complicated.
Processing will increase.

Further, in the above-described embodiment, even if the output image is a black and white image, when color recognition and color processing are performed, the color recognition and color processing can be performed using the same method. it can.

[0052]

[Second Modification] R output from the input masking unit 205
A color distribution detection unit that detects a color distribution based on GB data is provided in a system separate from the normal image processing unit. Then, the color distribution detection unit converts the RGB data output from the input masking unit 205 into a value on a uniform color space such as the L * a * b * color space,
By detecting the color distribution of the input image on the uniform color space and displaying the detected color distribution as a three-dimensional solid on the display unit,
The user is notified of the color distribution of the input image.

Then, the user arbitrarily changes the color distribution represented by the three-dimensional solid, and the CPU 214 sets various parameters such as masking based on the color distribution of the input image and the changed color distribution. That is, for example, the L * a * b * value at the representative point before the change and the changed L * a * value corresponding to the representative point
Calculate masking coefficient based on b * value
Set in R section 208.

In this way, since the color distribution is displayed in a three-dimensional solid, the user can more easily (visually) grasp the color distribution state.

As a method of detecting the color distribution, L * is previously set.
The color distribution of the input image is detected by dividing the a * b * color space into a plurality of blocks and sequentially setting flags corresponding to L * a * b * values.

Further, in the above-described embodiment, the input image is not limited to the image read from the original, but may be an image input from a device such as a host computer via a predetermined interface. . Similarly, the output image may be displayed on a display such as a CRT, LCD, or FLCD instead of being recorded on a recording paper. In this case, instead of the density display 22, the brightness (brightness) is displayed. ) Use the display. Furthermore, the hue information shown in FIG. 9 can also be output to the above display, which makes it possible to further facilitate image adjustment.

The present invention may be applied to a system composed of a plurality of devices or an apparatus composed of a single device.

Needless to say, the present invention can also be applied to the case where it is achieved by supplying a program to a system or an apparatus.

[0059]

As described above, according to the present invention,
It is possible to provide an image processing apparatus and a method thereof that can easily obtain a desired printout of hue and density.

[Brief description of drawings]

FIG. 1 is a diagram showing a configuration example of an image processing apparatus according to an embodiment of the present invention,

FIG. 2 is a block diagram showing a configuration example of an image processing unit shown in FIG.

FIG. 3 is a timing chart example of each control signal in the image processing unit,

FIG. 4 is a diagram showing an example of an image adjustment screen displayed on a display unit during image adjustment,

FIG. 5 is a diagram showing an example of an image adjustment screen displayed on a display unit during image adjustment,

FIG. 6 is a diagram for explaining hue adjustment,

FIG. 7 is a diagram showing an example of the operation unit shown in FIG.

FIG. 8 is a flowchart showing an example of an image adjustment procedure,

FIG. 9 is a diagram showing an example in which hue information of an output image is printed out.

[Explanation of symbols]

 A Reader section B Printer section 11 Hue display 13 Image adjustment section 14 Copy start button 22 Density display 214 CPU 217 Operation section 218 Display section

Claims (9)

[Claims] 1. An image processing apparatus for subjecting an input image to image processing and outputting the image, wherein display means for displaying hue information of the image after the image processing, and hue information displayed by the display means. Based on the instruction means for instructing the hue of the image after image processing, and setting means for setting the processing parameter of the image processing so that the hue instructed by the instructing means is obtained, the display means An image processing apparatus, wherein the hue information to be displayed is updated based on the hue instructed by the instructing means. 2. The image processing apparatus according to claim 1, wherein the display unit displays the hue information at the density or the brightness designated by the designating unit. 3. An image processing apparatus for performing image processing on an input image and outputting the image, wherein the output unit outputs the hue information of the image after the image processing, and the hue information output by the output unit. Based on the instruction means for instructing the hue of the image after image processing based on the image processing means, and a setting means for setting the processing parameter of the image processing so that the hue instructed by the instructing means is obtained, and the output means An image processing apparatus that outputs hue information updated based on the hue instructed by the instructing means. 4. The image processing apparatus according to claim 3, wherein the output unit outputs hue information at a plurality of densities or luminance levels. 5. An image processing method for subjecting an input image to image processing and outputting the image, wherein a display step of displaying hue information of the image after the image processing, and an image based on the displayed hue information. An instruction step for instructing the hue of the image after processing, and a setting step for setting the processing parameter of the image processing so that the instructed hue is obtained, the display step is based on the instructed hue. hand,
An image processing method characterized by updating hue information to be displayed. 6. An image processing method for performing image processing on an input image and outputting the image, wherein an output step of outputting hue information of the image after the image processing, and an image based on the output hue information. An instruction step for instructing the hue of the image after processing, and a setting step for setting the processing parameter of the image processing so that the instructed hue is obtained, the output step is based on the instructed hue. And outputting the updated hue information. 7. An input unit for inputting image data representing a document image, a detection unit for detecting a color distribution of the document image from the image data, a display unit for displaying the color distribution, and the displayed color. An instruction means for instructing a color distribution after color correction based on the distribution, and a color correction means for setting a color correction parameter based on the instruction of the instructing means and performing color correction on the image data. A characteristic image processing device. 8. The image processing apparatus according to claim 7, wherein the color distribution is displayed as a three-dimensional solid. 9. An input step of inputting image data representing a document image, a detection step of detecting a color distribution of the document image from the image data, a display step of displaying the color distribution, and the displayed color. An instruction step of instructing a color distribution after color correction based on the distribution, and a color correction step of setting a color correction parameter based on the instruction of the instruction step and performing color correction on the image data. Characterized image processing method.