JPH06268840A - Picture processor - Google Patents

Abstract

PURPOSE:To compose a 2nd picture onto a 1st picture like a watermark. CONSTITUTION:An operation section sets a read density of a 1st original picture and the picture of the 1st original is stored in a picture memory 102e. Then the picture of the 2nd original is read and inputted to a data processing section 102b and when the density of the picture data from the data processing section 102b is larger than a predetermined value, a selector 403 selects data from the data processing section 102b and when smaller than a predetermined value, the selector 403 selects data from the picture memory 102e.

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 having a function of synthesizing a plurality of images.

[0002]

2. Description of the Related Art Conventionally, for example, in a digital copying machine, an original is illuminated with a halogen lamp or the like, and the reflected light is photoelectrically converted using a charge-coupled device such as a CCD, and then converted into a digital signal to perform a predetermined process. After going, laser printer,
An image is formed using a recording device such as an inkjet printer.

In addition, not only in the analog copying machine but also in the digital copying machine, when the two originals A and B are superposed, the original A is first copied, and the original B is superposed on the copied paper. ing.

[0004]

However, in the above-mentioned prior art, when the superimposing process is performed, the image becomes dark at the portion where the originals A and B overlap each other, and the original data of the originals A and B is not reproduced. Is recorded with different data, the input image is not reflected in the output image.

[0005]

In order to solve the above problems, the present invention provides a memory for storing multivalued image data, a generating means for generating multivalued image data, and a generating means for generating the multivalued image data. Comparing means for comparing the value of the image data with a predetermined value in pixel units, and selecting one of the image data from the memory and the image data from the generating means in pixel units according to the comparison result of the comparing means. And selection means.

According to the present invention, a memory for storing multi-valued image data, a generating means for generating multi-valued image data,
Comparing means for comparing the value of the image data from the memory with the value of the image data from the generating means in pixel units; image data from the memory in pixel units according to the comparison result of the comparing means; Selecting means for selecting one of the image data from the generating means.

[0007]

According to the present invention, the second image is easily combined with the background portion of the first image.

Also, the first image is combined with the second image like a watermark.

[0009]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS [First Embodiment] Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.

(Structure of Copying Machine) FIG. 1 is a sectional view for explaining the structure of a copying machine which is an embodiment of the present invention.

In FIG. 1, reference numeral 1 denotes an original feeding device for automatically feeding originals, which feeds the stacked originals one by one or two in succession to a predetermined position on the original glass surface 2. To do. Reference numeral 4 denotes a scanner including an exposure lamp 3 for irradiating a document, a scanning mirror 5 for exposing and scanning the document, and the like. After the document is placed on the platen glass surface 2 by the document feeder 1, the scanner 4 Is scanned in the direction of A, and the reflected light from the original is CC through the scanning mirrors 5 to 7 and the lens 8.
An image is formed on the D image sensor 101. Reference numeral 10 denotes an exposure control unit including a laser scanner, which is a controller unit CO
The photoconductor 11 is irradiated with the light beam modulated based on the image data output from the image signal control unit of NT. 12
Is a red developing device, 13 is a black developing device, and visualizes the electrostatic latent image formed on the photoconductor 11 with red and black developers (toners). One of the developing devices 12 and 13 is disposed close to the photosensitive drum 11 by the developing device switching device 30, and the other is retracted from the photosensitive drum 11. Further, when performing the multiple phenomenon, the controller unit CONT controls the developing device switching device 30. A sheet stacking unit 14 and 15 stacks and stores standard size sheets. The sheet is fed to the position where the registration rollers 25 are arranged from the stacking units 14 and 15 by driving the feeding rollers, and the leading edge of the image formed on the photoconductor 11 by the registration rollers 2 and the leading edge of the sheet are aligned. It is delivered at the timing.

A transfer / separation charger 16 transfers the toner image of the photoconductor 11 onto a sheet and then separates the sheet from the photoconductor 11. After that, the sheet fixes the toner on the sheet by the fixing unit 17 via the conveyance belt. A paper discharge roller 18 discharges the recorded sheet to the tray 20. Two
1 switches whether the sheet recorded by the direction flapper is discharged to the tray 20 side or is conveyed to the internal conveyance paths 22, 23, 24.

During double-sided recording, the flapper 21 is placed in the tray 20.
Immediately after the trailing edge of the sheet has passed the sheet discharge sensor 19, the sheet discharge roller 18 is rotated in the direction opposite to the sheet discharge direction at the same time as the flapper 21 is set.
Is raised to store the copied sheets in the intermediate tray 24 via the transport paths 22 and 23. At the next recording on the back surface of the sheet, the sheet stored in the intermediate tray 24 is fed and the transfer is performed on the back surface of the sheet.

(Outline of Processing) FIG. 2 is a block diagram of the copying machine of this embodiment.

A full-color original is exposed by the exposure lamp 3 and the reflected color image is read by the CCD image sensor 10.
The image signal is picked up by No. 1, the picked-up image signal is processed, processed, and output to the printer 103.

The color information of the original 100 is obtained by the image reading unit 1.
CCD image sensor 1 through lens 101a of 01
The image is formed at 01b. The CCD image sensor 101b outputs an image of each line of the document to R (red), G (green), B (blue).
Each is read at a resolution of 400 dpi (dot per inch). The read signal is output as an analog signal, and an A / D that converts the analog signal into a digital signal
It is input to the converter 101c. A / D converter 1
The digital signal from 01c is input to the image processing unit 102. In the image processing unit 102, shading correction is performed by the shading correction circuit 102a to generate image data of 8 bits for each of R, G, and B.

In the data processing unit 102b, various kinds of image processing are performed on the R, G and B image data read by the CCD image sensor 101b to create 8-bit black and white luminance image data. This is used when a color original image is printed in black and white.

The image memory 102e is a data processing unit 102.
The multivalued image data from b is stored, and the image data is output to the image synthesizing unit 102d.

The image processing section 102c includes a data processing section 10
2b and the data from the image memory 102e are selected for each pixel and output.

The output of the image synthesizing unit 102c is input to the brightness / density converting unit 102d, the brightness data is converted to density data by the brightness / density converting unit 102d, and the converted data is input to the printer 103. The printer 103 includes a control circuit such as a motor that conveys a sheet, a laser recording unit that writes input image data on a photosensitive drum, and a development control circuit that performs development. The CPU circuit unit 104 corresponds to the controller unit CONT in FIG. 1, and includes the CPU 104a and the ROM 104.
b, has a RAM 104c, controls the image reading unit 101, the image processing unit 102, the printer 103, etc., and generally controls the sequence of the copying machine.

(Image Synthesizing Unit) FIG. 3 shows the image synthesizing unit 102c.
It is a detailed block diagram of.

In this embodiment, the data from the data processor 102b is combined with the data from the image memory 102e as a watermark image.

Since the data from the data processing unit 102b and the data from the image memory 102e are luminance data, the data 255 is "white" and the data 0 is "black".

In order to determine the white area of the data from the data processing unit 102b, in this embodiment, a predetermined value is set in the register 402 by the CPU, and the value set in the register 402 and the data from the data processing unit 102b are set. Are compared by the comparator 401. The comparator 401 outputs "1" when the data from the data processing unit 102b is larger than the value set in the register 402. In the selector 403, the data output from the data processing unit 102b and the data output from the image memory 102e are selected and output according to the output signal.

Therefore, the conversion table selection signal "0"
In the case of, the selector 403 outputs the data from the data processing unit 102b, and when the conversion table selection signal is "1", the selector 403 outputs the data from the image memory 102e.

The conversion table selection signal and the output data of the selector 403 are input to the brightness / density conversion unit 102d.

(Brightness Density Conversion Unit) In the brightness density conversion unit 102d shown in FIG. 2, brightness density conversion for converting brightness data into density data using a LUT (lookup table) and gradation correction for correcting the gradation of the printer are performed. Done.
First, the brightness / density conversion processing converts the read brightness signal into a density signal, and is generally called log conversion. The log conversion table is calculated from the following equation.

Dout = 255 / Dmax × log (Din / 255) (1) (Dmax is the maximum density value output by the printer) Next, gradation correction will be described. The gradation correction table is
It corrects the gradation of the printer output, for example,
The gradation characteristics of the electrophotographic printer are shown by the solid line in FIG. The correction table for it is shown by the solid line in FIG.

In this embodiment, the correction processing is performed by the same RAM, and correction data = gradation correction (−255 / Dmax × log)
(Din / 255)) The conversion table obtained from (2) is written in the RAM 104c.

Further, in this embodiment, the data processing unit 102b
Conversion table and image memory 102 for image data from
A conversion table for image data from e is prepared for each, and the data from the image memory 102e is configured to be output as an image of the watermark portion. Assuming that the conversion table for the data processing unit 102b is the conversion table A and the conversion table for the image memory 102e is the conversion table B, the conversion table A is written with the data obtained by the above equation (2). Data for the watermark portion is written in the conversion table B, and the log conversion table for the watermark image is changed as in the following equation.

Dout = −255 / Dmax × log (Din / 255) / α (α ≧ 1) (3) Therefore, the conversion table B is: correction data = gradation correction (−255 / Dmax × log
(Din / 255) / α) The data obtained by (4) is written.

In this equation (4), α is changed according to the setting of the density of the watermark image. That is, when the density of the watermark image is increased, α becomes a value close to 1, and as α is increased, the density of the watermark image decreases. This α
The value of, depending on the setting of the watermark image from the operation unit described later,
It is configured to be set each time.

In this embodiment, each conversion table for density conversion and gradation correction is composed of the RAM 405 as shown in FIG. 5, and the data of the conversion table is created by the program of the CPU and written in the storage element 405. .

The conversion table created as described above is selected for each pixel by the conversion table selection signal and the luminance signal is converted into the density signal. When the table selection signal is "0", the conversion table A in the RAM 405 is selected, and when the table selection signal is "1", RA is selected.
The conversion table B in M405 is selected.

(Operation Unit) FIG. 6 shows the operation unit of the copying machine in this embodiment.

In FIG. 6, the display unit 51 indicates the state of the device,
Displays the number of copies, copy paper size, copy mode, etc.

The control key 52 is a key for moving the pointer displayed on the display unit 51 up, down, left and right in each function setting screen.

The OK key 53 is pressed when the set conditions are good on each function setting screen.

The function key 54 is pressed to execute the setting output at the lower right of the display section 51 on each function setting screen.

The numeric keypad 55 is used to input a numerical value on each function setting screen.

The start key 56 is used to start the copy operation.

The option memory key 57 is used when executing watermark copy using the option memory.

The reset key 58 is used to return to a predetermined standard mode.

(Watermark copy setting procedure) With reference to FIGS. 7 and 8, a method of setting a watermark copy in the above-mentioned operation unit will be described.

FIG. 7A shows a standard screen of the display section 51 of FIG.

When the option memory key 57 is pressed,
The screen shown in FIG. 7B is displayed. On this screen, the control key 52 is used to move the cursor to watermark composition as shown in FIG. 7C, and the OK key 53 is pressed to display the screen shown in FIG. 7D. The output density of the watermark image is set on this setting screen. 1 when outputting at normal output density
To decrease the value of 00, the value is decreased and the numeric value is input by the control key 52 or the ten key 55.
As for the correspondence with α in the equation (4), α = 100 / x (5), where x is the numerical value of the density input by the operation unit. After inputting the numerical values, the OK key 53 is pressed, and then the paper size is set on the screen of FIG.
After that, as shown in the screen display of FIG. 8F, the document B to be output as a watermark is set on the document table and the OK key 52 is pressed. Image of this document is read and image memory 1
While being set to 02e, the display as shown in FIG. 8 (g) is displayed. When the image storage is completed, the screen shown in Fig. 8 (h) appears,
When the document is converted into the document A and the start key 56 is pressed, the image stored in the image memory 102c and the image of the document being read are selected in pixel units, and image synthesis is performed by the circuit of FIG.

The value set in the register 402 of FIG. 3 is configured so that the operator can freely set it by the operation unit (not shown). Therefore, for example, if the set value is increased, the white area of the original image is increased. If the image in the memory is combined and the set value is reduced, the image in the memory is combined not only in the white area of the original image but also in the gray area.

As described above, according to the first embodiment, when the document B is combined with the document A as the watermark image, the means for setting the density of the watermark image is provided. The density can be changed, and the original B can be effectively combined.

FIG. 11 shows an output example of a composite image.

[Second Embodiment] In the first embodiment, the conversion table is created in the brightness density conversion unit 102d so that the watermark image also has gradation.

However, when it is premised that the original B is output as a watermark, it is desirable that the output density of the image is low. Therefore, a watermark image can be generated sufficiently effectively even if it has little gradation. It is possible. Therefore, in this embodiment, when setting the output density of the watermark image using the conversion table, the conversion table is created by limiting the maximum output density value.

That is, the correction data is limited to the data subjected to the log conversion and the gradation correction processing according to the set value of the density of the watermark image. Output data for watermark image is watermark data, maximum output data is THR
Then, it becomes as follows.

When correction data ≧ THR, watermark data = THR When correction data <THR, watermark data = correction data (6) (THR ≦ 255) (correction data = gradation correction (-25
5 / Dmax × log (Din / 255)))

Here, when the density of the watermark image is increased, THR is increased, and when the density of the watermark image is decreased, THR is decreased. The value of THR is configured to be set each time according to the setting of the watermark image from the operation unit. Regarding this setting, if the input value on the setting screen of FIG. 7D is x, then it is as shown in equation (7).

THR = 255 × x / 100 (7) Regarding the creation of the conversion table for the density conversion, gradation correction, and watermark correction, all of them are created by the program of the CPU and written in the RAM. It is also possible to store the conversion tables for density conversion and gradation correction in the ROM, and combine the data with the watermark correction to write them in the RAM or the like.

Since the other structure is the same as that described in the first embodiment, the description thereof will be omitted.

[Third Embodiment] FIG. 9 shows an image synthesizing section 102.
It is a block diagram of the other Example of c.

The selector 1203 includes a data processing unit 102.
The image data from b and the image data from the image memory 102e are input. In addition, the upper 4 bits of the image data from the image processing unit 102b are input to the AND gate 1201 and are ANDed with each bit. Here, since the signal input to the selector 1203 is luminance data, the data 255 is “white” and the data 0 is “black”. In this embodiment, when the data is 240 or more, it is determined to be “white”. That is, A of the upper 4 bits of the image data
This is when ND is "1". Next, the AND gate 120
The output of 1 is sent to the selector 1 via the AND gate 1202.
It is input to 203. The AND gate 1202 controls selection between normal image formation and composite image formation, and "0" is input to one input terminal of the AND gate 1202 when a normal copy is performed without using a memory. Therefore, "1" is input when the combination is performed. Therefore, when synthesizing, either the image data from the original document or the data stored in the image memory 102e is selected by the output of the AND gate 1202. That is, when it is determined that the image data from the data processing unit 102b is "white", the 4-input AND gate 1201 outputs "1" and selects the data from the image memory 102e. When it is determined that the image data from the data processing unit 102b is not white, the image data from the data processing unit 102b is selected, output from the selector 1203, and input to the brightness / density conversion unit 102d.

Since the other structure is the same as that described in the first embodiment, the description thereof will be omitted.

[Fourth Embodiment] In the above-described embodiment, the data from the data processing unit 102b is combined with the data in the image memory 102e as a watermark image, but in the present embodiment, the data from the data processing unit 102b is combined. Image memory 1
In addition to combining the data from the image processing unit 02b, the data from the image memory 102e can be combined with the data from the data processing unit 102b. FIG. 10 shows the configuration of the image composition unit 102c for that purpose.

When the data from the image memory 102e is used as watermark data, the CPU 104a sets "0" in the register 1504, and the selector 1501 selects and outputs the data from the data processing unit 102b. The output of the selector 1501 is the comparator 15
At 02, the value is compared with the value set in the register 1503 by the CPU 104a, and when the output of the selector 1501 is larger than the set value of the register 1503, that is, when the image data from the data processing unit 102b is “white”, 1 ”is output. At this time, since the output of the register 1501 is "0", the EXOR gate 1505 also outputs "1", and the selector 1506 outputs the image memory 102e.
Select and output the data from. Data processing unit 102b
When the image data from is not "white", the output of the comparator 1502 becomes "0", and the EXOR gate 150
The output of 5 becomes "0", and the selector 1506 selects and outputs the data from the data processing unit 102b.

When the data from the data processing unit 102b is used as watermark data, the CPU 104a may set "1" in the register 1504. That is,
The selector 1501 selects and outputs the data from the image memory 102e. When the output of the selector 1501 is larger than the set value of the register 1503, the comparator 15
Since 02 outputs “1”, the EXOR gate 1505
Outputs "0". Therefore, the selector 1506 selects and outputs the data from the data processing unit 102b. On the other hand, when the set value of the register 1503 is larger than the output of the selector 1501, the comparator 1502 outputs "0", so the EXOR gate 1505 outputs "1". Therefore, the selector 1506 selects and outputs the data from the image memory 102e.

Further, in the brightness density conversion unit 102d,
The conversion table data for the watermark image is set according to the selection of the watermark image in the conversion table. That is, when the data from the image memory 102e is used as the watermark data, the conversion table for the watermark image is created in the conversion table B, and the conversion table A is created.
A normal conversion table is created in. When the data from the data processing unit 102b is used as the watermark data, the reverse is true.

The rest of the structure is the same as that described in the above-mentioned embodiment, so the explanation is omitted.

According to this embodiment, as shown in FIG. 11, it is possible to obtain the output image of (c) by combining the original of (a) and the original of (b).

[Fifth Embodiment] FIG. 12 shows an image synthesizing section 10
It is a block diagram which shows the other Example of 2c.

The data processing unit 1 is included in the comparator 2201.
8-bit image data from 02b and image memory 102
The 8-bit image data from e is input, the comparator 2201 outputs "1" when the value of the data from the image memory 102e is smaller than the value of the data from the data processing unit 102b, and the comparator 2201 outputs the data processing unit 102b. When the value of the data from is small, "0" is output. here,
Since the data input to the comparator 2201 is luminance data, the data value 255 is “white” and 0 is “black”.
Has become.

The selector 2202 is a comparator 2201.
When the output of 1 is "1", the data from the image memory 102e is output, and when the output of the comparator 2201 is "0", the data from the data processing unit 102b is output. That is, the selector 2202 selects and outputs the smaller one of the data from the data processing unit 102b and the data from the image memory 102e, that is, the one with the higher density.

The output of the selector 2202 is then input to the brightness / density converter 102d.

The other structure is the same as that described in the above-mentioned embodiment, and the description thereof is omitted.

According to this embodiment, as shown in FIG. 13, it is possible to obtain the output image of (c) by synthesizing the original of (a) and the original of (b). At this time, if the image of (b) is stored in the image memory 102e, a new original and (b)
It is not necessary to scan the image of (b) again and store it in the image memory when the images of (1) and (2) are combined.

As described above, according to the fifth embodiment, when the original A and the original B are combined, the one with smaller data (higher density) is selected and output.
The input image is reflected in the output image, and the overlapped portion due to the multiple transfer does not become darker than the density of the original document as before, and a good composite image can be obtained.

[Sixth Embodiment] In the fifth embodiment, the image data is compared for each pixel, and the synthesizing process is performed by selecting the smaller data (higher density).

In this embodiment, the image data is compared for each pixel, and the one having the larger data (the one having the lower density) is selected. FIG. 14 shows the configuration of the image composition unit 102c for that purpose.

The difference from the fifth embodiment is that the selector 23
It is to be inverted by the output inverter 2302 of 01. Therefore, when the data from the data processing unit 102b is larger than the data from the image memory 102e, the comparator 2301 outputs "1" and the inverter 2
It is inverted by 302 and input to the selector 2303,
The selector 2303 selects and outputs the data from the data processing unit 102b. When the data from the image memory 102e is larger than the data from the data processing unit 102b, the data from the image memory 102e is output.

The output of the selector 2303 is input to the brightness / density converter 102c.

Since the other structure is the same as that described in the first embodiment, the description thereof will be omitted.

By configuring as described above, FIG.
As shown in (1), the original (a) and the original (b) can be combined to obtain an output image of the original (c). To put the pattern shown in the original (b) on the black part of the original (a),
It becomes possible to perform decoration processing.

[Seventh Embodiment] In this embodiment, the data processing unit 102b and the data from the image memory 102e can be selected to be smaller or larger. FIG. 16 shows the configuration of the image composition unit 102c for that purpose.

The comparator 2401 is the data processing unit 10.
When the data from 2b is larger than the data from the image memory 102e, "1" is output. Comparator 2
The output of 401 is input to the EXOR 2403. Next, "0" is set in the register 2402 when the smaller data is selected by the CPU 104a,
When the data is large, "1" is set.

Therefore, when the output of the comparator 2401 is “1” and the register 2402 is set to “0”, the output of the EXOR 2403 becomes “1” and the selector 2404 causes the image memory 102 having a small data value.
Output the data from e.

Since the subsequent processing is the same as that described in the fifth and sixth embodiments, the description thereof will be omitted.

The data setting in the register 2402 is performed by the CPU 102c based on the input from the operation unit.

When a watermark image is combined with the "white" area in the above-described first to fourth embodiments, a "white" image close to "black" is obtained as in the fifth to seventh embodiments. It is also possible to select the one having the higher density of the region image and the watermark image.

[0085]

As described above, according to the present invention, it is necessary to detect a white area instead of an area having a high density such as a character of an image and synthesize another image in the area. It is possible to satisfactorily synthesize images such as watermarks while holding the images.

Further, according to the present invention, when synthesizing images, the smaller image data or the larger image data (higher density or lighter density) is selected. The data of the input image is reflected in the output image, the density of the portion where the data overlaps does not become dark, and the image decoration processing for placing the pattern on the black portion of the document can be performed well.

[Brief description of drawings]

FIG. 1 is a sectional view of a copying machine according to an embodiment of the present invention.

FIG. 2 is a block diagram for performing image processing of a copying machine.

FIG. 3 is a configuration diagram of an image synthesizing unit 102c.

FIG. 4 is a diagram illustrating tone characteristics of a printer and characteristics of a correction table.

FIG. 5 is a configuration diagram of a brightness density conversion unit 102d.

FIG. 6 is a diagram showing an operation unit.

FIG. 7 is a diagram showing an operation procedure of watermark composition.

FIG. 8 is a diagram showing an operation procedure of watermark composition.

FIG. 9 is a configuration diagram of an image composition unit 102c according to a third embodiment.

FIG. 10 is a configuration diagram of an image composition unit 102c according to a fourth embodiment.

FIG. 11 is a diagram showing an output example of an image in the present invention.

FIG. 12 is a configuration diagram of an image composition unit 102c according to a fifth embodiment.

FIG. 13 is a diagram showing an output example of an image in the fifth embodiment.

FIG. 14 is a configuration diagram of an image composition unit 102c according to a sixth embodiment.

FIG. 15 is a diagram showing an output example of an image in the sixth embodiment.

FIG. 16 is a configuration diagram of an image composition unit 102c according to a seventh embodiment.

Front page continued (72) Inventor Satoru Eda 3-30-2 Shimomaruko, Ota-ku, Tokyo In Canon Inc. (72) Inventor Keizo Isemura 3-30-2 Shimomaruko, Ota-ku, Tokyo In Canon Inc.

Claims (3)

[Claims] 1. A memory for storing multi-valued image data, a generation means for generating multi-valued image data, and a comparison means for comparing the value of the image data from the generation means with a predetermined value in pixel units. An image processing apparatus comprising: image data from the memory on a pixel-by-pixel basis in accordance with the comparison result of the comparison means; and selection means for selecting one of the image data from the generation means. 2. A memory for storing multi-valued image data, a generation means for generating multi-valued image data, a value of the image data from the memory and a value of the image data from the generation means in pixel units. And a selecting means for selecting one of the image data from the memory and the image data from the generating means on a pixel-by-pixel basis in accordance with the comparison result of the comparing means. Image processing device. 3. The density setting means according to claim 1, further comprising density setting means for independently setting the density of the image data stored in the memory and the density of the image data generated by the generating means at the reproduction output. Image processing device.