JPH04294680A - Image processor - Google Patents

Abstract

PURPOSE:To record an overlapped part in a desired overlay recording color even when an original image is overlapped on an overlay image in the case of performing the overlay recording of a color image. CONSTITUTION:Density data set on an overlay image density register 31 is outputted conforming to a color signal when the overlay image is printed corresponding to overlay picture element data in IC card memory 28. A selector 30 which outputs original image density data of separation color in accordance with the color signal from an image processing part 29 when no overlay image is printed is provided.

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 a digital copying machine or the like.

0002

2. Description of the Related Art There are known digital copying machines that have an overlay function for combining original image data with overlay image data stored in an IC card memory. FIG. 4 shows the configuration of a conventional copying machine. The document image read by the reader unit 1 is separated into blue, green, and red color light, and the image data corresponding to each color is converted from BGR to MCY in the image processing unit 2.
Color correction, density processing, etc. are performed to obtain converted image density data of each separated color of magenta, cyan, and yellow. The image density data for each separated color of magenta, cyan, and yellow is such that only one of them is selected by a color signal for selecting one of magenta, cyan, and yellow from the printer section 5, and the image density corresponding to that color is determined. The data is sent to the OR circuit 3.

On the other hand, overlay image data is stored in the IC card memory 6, and the same color signal given to the image processing section 2 from the printer section 5 is sent to the CPU 7.
The overlay image data is sent to the OR circuit 3 in accordance with the color signal under the control of the CPU 7.

[0004] Whether or not an overlay image is read out from the IC card memory 6 is also determined by the overlay recording color specified by the operation unit 4. for example,
When red is selected as the overlay recording color, the CPU 7 selects the IC card only when a magenta selection signal and a yellow selection signal are input from among the color signals given to the CPU 7 from the printer unit 5 to reproduce red. The overlay image data in the memory 6 is controlled to be read. The image data thus outputted from the image processing section 2 and the IC card memory 6 are combined by the OR circuit 3, and then supplied to the printer section 5 and printed.

[0005]

[Problems to be Solved by the Invention] In the conventional digital copying machine described above, the overlay image data is simply OR-combined with the original image data, so the desired overlay recording color is not displayed in the area where the original image and the overlay image overlap. The drawback was that it was not available.

To explain in more detail, consider a case where an overlay image "m" is printed over a document image "A" as shown in FIG. 3. Consider a case in which the original image "A" is green (therefore, it is reproduced in green), and the overlay image "m" is set to reproduce the recording color in red.

For original image "A", when the color signal is a cyan selection signal and a yellow selection signal, image data having a predetermined density in a portion corresponding to the image is output to the OR circuit 3. . For overlay image "m", image data having a predetermined density in a portion corresponding to the image is output to the OR circuit 3 when the color signals are the magenta selection signal and the yellow selection signal.

By printing with the printer section 5 using such image data, the original image "A" shown in FIG.
Most of the overlay image "m" (the part that does not overlap with the overlay image "m") is printed in green, and most of the overlay image "m" (the part that does not overlap with the original image "A") is printed in red. However, in the area where original image "A" and overlay image "m" overlap, image data with a predetermined density for each color of magenta, cyan, and yellow is output, so red is the desired overlay recording color. Sometimes I couldn't get it.

SUMMARY OF THE INVENTION An object of the present invention is to provide an image processing apparatus that can faithfully reproduce overlay recording colors even in areas where a document image and an overlay image overlap.

0010

[Means for Solving the Problems] A first image processing apparatus according to the present invention includes an original image density data output means for color-separating an original image and outputting image density data of each separated color, and a recording color of an overlay image. overlay image density data generation means for generating overlay image density data for each separated color according to the overlay image density data, overlay pixel data generation means for generating overlay pixel data indicating whether or not the overlay image is printed, The present invention is characterized in that it includes a data selection means that outputs overlay image density data when the overlay pixel data is not printed, and outputs original image density data when the overlay pixel data is not printed.

[0011]

[Operation] In the image processing device according to the present invention, when the overlay pixel data is data indicating that printing is present, the overlay image density data of each separation color corresponding to the recorded color of the overlay image is data that the overlay pixel data is data indicating that there is no printing. When this is the case, original image density data for each separated color obtained by color-separating the original image is output from the data selection means.

0012

DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment in which the present invention is applied to a digital color copying machine will be described below with reference to FIGS. 1 to 3.

FIG. 1 shows a schematic diagram of a digital color copying machine, in which a color document placed on a contact glass 8 so as to be pressed by a document holder 9 is scanned by a scanning optical system constituting a color scanner. The image information is guided from a condensing lens 10 to a light receiving element 11 such as a CCD using light as a medium, where it is converted into an electrical signal, and then subjected to signal processing in an image processing circuit 12. The photosensitive drum 1 is scanned by the scanner unit 13.
4 as a latent image. Further, as will be described later, the image data of the overlay image is also subjected to signal processing by the image processing circuit 12 and combined with the original image data. Prior to this, the surface of the photosensitive drum 14 is charged by the main charger.

When forming a color image, when the M developing device 15 is positioned so as to face the photosensitive drum 14, a color signal, which will be described later, is sent to the image processing circuit 12.
First, a latent image is formed on the photosensitive drum 14 by a laser beam based on magenta image density data, and the latent image is developed by the M developing device 15. The M developing device 15 has magenta toner and develops the latent image on the photosensitive drum 14 with an amount of magenta toner determined based on magenta image density data. The image formed on the photosensitive drum 14 by the magenta toner is transferred onto a sheet of paper wrapped around the surface of the transfer drum 16.

[0015] This paper is mounted as it is on the surface of the transfer drum 16 and is used for the next transfer. That is, the photosensitive drum 1
4, after the residual toner is wiped off by the cleaning section and the static electricity is removed by the static eliminator (not shown), the main charge is removed again.
When the C developing device 17 is positioned so as to face the photosensitive drum 14, a color signal (described later) is sent to the image processing circuit 12, and a laser beam is generated based on the cyan image density data. A latent image formed by the beam on the photosensitive drum 14 is developed by a C developing device 17.

In this embodiment, the developing devices include an M developing device 15 for developing magenta, and a C developing device 1 for developing cyan.
7. A Y developing device 18 for developing yellow and a BK developing device 19 for developing black are sequentially mounted in the vertical direction on a movable body 20 that moves in the vertical direction as shown.

Now, the image developed with cyan toner on the photosensitive drum 14 is transferred to a sheet of paper (on which a magenta image has been previously transferred) on the surface of the transfer drum 16. In the same manner, yellow and black images are further transferred to the paper to form a full color image. Thereafter, the paper on which the color image has been formed is separated from the transfer drum 16, fixed in a fixing section, and then discharged from the copying machine.

Next, referring to FIG. 2, the image processing circuit of the present invention will be explained. The image processing circuit 12 is supplied with original image data from a reader unit 25 including the light receiving element 11 and the like and overlay image data from an IC card memory 28 . The image processing circuit 12 is also provided with information input through the operation unit 26 . The image processing circuit 12 performs desired image processing based on these image data and input information, and sends the image processing data to a printer section 27 including a laser scanner unit 13 and the like. The printer section performs image formation as described above based on this data.

The image processing circuit 12 will be explained in more detail. The image processing circuit 12 has an image processing section 29, and the document image read by the reader section 25 is blue, green,
It is decomposed into image density data of three colors of red and input to the image processing section 29 . In the image processing unit 29, BGR→MCY
By performing the conversion, original image density data is obtained for each separated color of magenta, cyan, and yellow. Furthermore, the image processing section 29 includes a circuit for correcting document image density data for each separated color of magenta, cyan, and yellow, and a circuit for performing density processing. Image processing section 29
From the original image density data of each of the separated colors of magenta, cyan, and yellow obtained in step 1, only the original image density data of one color is selected by the color signal provided from the printer section 27 and sent to the selector 30. For example, when the M developing unit 15 is positioned opposite the photosensitive drum 14 in the printer section 27, the color signal is a signal for selecting magenta, and the image processing section 29 receives magenta document image density data. It is now output. Further, the image density data sent from the image processing section 29 to the selector 30 is sent in, for example, an 8-bit configuration.

On the other hand, the overlay image is stored in the IC card memory 28. The overlay image stored in the IC card memory 28 is stored as overlay pixel data in which one bit corresponds to one pixel. If the data of the pixel of interest is "1", it indicates that the overlay image is printed for that pixel, and if the data is "0", it indicates that there is no printing. In this way, since the overlay image is stored as 1-bit data with and without printing, the memory area can be saved significantly. Furthermore, as will be described later, this data can be used as is as a selection signal, which has the effect of simplifying the circuit configuration. This overlay pixel data is input to the selector 30 as a selection signal, and the overlay image density register 31
is input as a synchronization signal.

The density of the overlay image is determined by the setting value of the overlay image density register 31. The set value of the register 31 is controlled as follows. That is,
The register 31 is controlled by the CPU 32 and is
The PU 32 is given a color signal from the printer section 27 and information specifying the recording color of the overlay image from the operation section 26 . The CPU 32 further includes a ROM 33,
A RAM 34 is connected, and data as shown in Table 1 is stored in the ROM 33.

[0022]

[Table 1]

In Table 1, N represents the density setting value, which is stored as 8-bit data. For example, if the recording color of the overlay image specified from the operation unit 26 is red and the color signal from the printer unit 27 is magenta, the CPU 32 refers to the ROM 33 and stores the 8-bit data in the register 31. Set the density setting value N. Then, when the color signal switches from magenta to cyan, the density setting value 0 is set in the register 31 with reference to the ROM 33 in the same way. Similar processing is performed for yellow. The set value of the register 31 is input to the selector 30.

The selector 30 selects the overlay pixel data as "1" (overlay image printed) according to the overlay pixel data (selection signal) in the IC card memory 28.
If so, select the data from the overlay image density register 31, and if the overlay pixel data is "0" (no overlay image printing), select the original image data from the image processing section 29 and send it to the printer section 27. Make it.

The overlay image is accurately reproduced by inputting the overlay pixel data stored in the IC card memory 28 to the overlay image density register 31 as a synchronization signal.

Next, the operation of this embodiment will be explained. Consider a case where an overlay image "m" is printed over a document image "A" as shown in FIG. 3. Manuscript image "
A” is green (and therefore reproduced as green)
, a case where the overlay image "m" is set on the operation unit 26 so that the recorded color is reproduced in red. In addition, in FIG. 3, the area where image "A" and image "m" overlap is X, the area where area X is removed from image "A" is Y, and the area where area X is removed from image "m". Let Z be the area of .

A magenta color signal is sent from the printer section 27 to the image processing section 29 and the CPU 32. The image processing unit 29 sends the magenta original image density data to the selector 30 among the color-separated magenta, cyan, and yellow original image density data. In this case, since the original image was originally green, "0" is output as magenta original image density data.

On the other hand, since the recording color from the operation section 26 is red and the color signal from the printer section 27 is magenta, the CPU 32 sets the density setting value N in the overlay image density register 31 with reference to Table 1. , selector 3
Output the set value to 0.

Since the pixel data "1" is outputted from the IC card memory 30 so as to correspond to the overlay image "m", the selector 30 stores only the portion corresponding to the image "m" in the register 31 as overlay image density data.
The density setting value N set in is output to the printer. Density data from the image processing unit 29 is output for the portions other than the image “m”, but in this case, 0 is output, so as a result, magenta printing is performed only on the portion of the image “m”. If this is represented by the regions defined above, regions X and Z have a density N.

Next, when the cyan color signal is sent from the printer section 27 to the image processing section 29 and the CPU 32, the image processing section 29 sends cyan original image density data to the selector 30. On the other hand, since the recording color from the operation unit 26 is red and the color signal from the printer unit 27 is cyan, the CPU 32 sets the density setting value 0 in the overlay image density register 31 and outputs the setting value to the selector 30. do it like this.

Since the pixel data "1" is outputted from the IC card memory 30 to correspond to the overlay image "m", the selector 30 stores only the portion corresponding to the image "m" in the register 31 as overlay image density data.
The density setting value 0 set in is output to the printer. However, in this case, since the density setting value is 0, the portion corresponding to image "m" is not printed. Since the cyan density data from the image processing unit 29 is output for the parts other than the image "m", only the part of the image "A" excluding the overlapping part between the images "A" and "m" in FIG. is printed. If this is expressed as an area, area Y becomes the document reading density.

Similarly, when the color signal is yellow, expressed by areas, area Y is the document reading density, and areas X and Z are the density N.

As described above, by printing using each separated color, the areas X and Z have a density N of magenta and yellow, respectively.
Since they are superimposed, the entire overlay image "m" is expressed in red. In addition, in area Y, cyan and yellow are superimposed at the document reading density, so the image "A"
" can reproduce the color tone of the original except for the part that overlaps with the image "m".

Note that printing using each separated color as described herein means that, in the case of a copying machine as shown in FIG. 1, toners are superimposed on transfer paper and then fixed. In this embodiment, the data in the format shown in Table 1 is stored in the ROM 33, but the data is not limited to this and may be stored in the RAM 34, or the data may be input sequentially from the operation unit 26. good. Further, the density setting values listed in Table 1 may be changed arbitrarily. This makes it possible to change the tone of the overlay recording color and further increase the number of recording colors. That is, by using the overlay density setting register, it has become possible to easily change the color tone of the overlay image. Furthermore, in this embodiment, the processing for each separated color is performed sequentially using the color signal supplied from the printer section 27, but three systems of selectors 30 and registers 31 are provided for each separated color to perform parallel processing. Good too.

[0035]

As explained above, according to the present invention, even when a document image and an overlay image overlap, it is possible to print the entire overlay image in a desired recording color without causing any color change in the overlapping portion. can.

[Brief explanation of drawings]

FIG. 1 is a schematic diagram of a digital color copying machine to which the present invention is applied.

FIG. 2 is an electrical block diagram schematically showing the present invention.

FIG. 3 is a diagram showing an example of a copy image obtained by an overlay function.

FIG. 4 is an electrical block diagram showing a conventional example.

[Explanation of symbols]

12 Image processing circuit 28 IC card memory 29 Image processing section 30 Selector

Claims (1)

[Claims] 1. Document image density data output means for color-separating a document image and outputting image density data for each separated color;
overlay image density data generation means for generating overlay image density data for each separated color according to the recording color of the overlay image; overlay pixel data generation means for generating overlay pixel data indicating whether or not the overlay image is printed; and overlay pixel data. An image processing apparatus comprising: data selection means for outputting overlay image density data when the data includes printing, and outputting original image density data when the overlay pixel data indicates no printing.