JPH0519862B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to an image processing apparatus, and particularly to an image processing apparatus that synthesizes an image and a dot pattern.

[Conventional Apparatus] Apparatuses such as inkjet printers, thermal transfer printers, and laser beam printers are conventionally known. Such devices employ various halftone processing methods to reproduce halftones.

Furthermore, there are cases where it is desired to synthesize dot patterns such as letters or specific line patterns with the above-mentioned halftone image.

In such a synthesis, for example, monochrome image synthesis can be easily carried out by, for example, taking the logical sum of a monochromatic halftone image and a dot pattern.

However, in order to synthesize a color halftone image and a dot pattern of a desired color, for example, in plate-making technology for printing, a plate for each color of Y, M, C, Bk of the color halftone image and a dot pattern of a desired color are used. The process involved creating a dot pattern of the desired color separately, combining the plates optically by hand rather than electrically, and finally creating the printing plate. The problem was that it was necessary and difficult to perform accurately.

Moreover, such plate-making technology could not be immediately applied to color printing technology.

[Object of the Invention] In view of the above problems, it is an object of the present invention to provide an image processing device that can electrically easily synthesize a color image and a desired color dot pattern at high speed with high precision.

For this purpose, the present invention provides an image processing device for a color printer (corresponding to FIGS. 1 to 6 in the embodiment) that sequentially forms images for each color component for a plurality of color components, A first generating means for generating color image information of color components corresponding to the image forming operation of each color component in the color printer (corresponds to the transfer from the dither processing circuit 24 of FIG. 1 to the image memory 21 in the embodiment) a memory (also 8) in which pattern information different from the color image information is stored as a dot pattern; and means (also corresponding to the write position designation circuit 15) for storing a predetermined dot pattern in the memory; a second generating means (corresponding to a signal inputted from line 112) for generating designation information specifying the image forming color of the dot pattern; and changing the image forming sequence for each color component of the color printer. In order to be able to color the dot pattern according to the designated information and synthesize it into the color image information, the dot pattern stored in the memory can be read out at a timing corresponding to the image forming operation of each color component. means (also a control circuit 16); and a composition means (also an OR gate 7) for outputting a composition signal based on the dot pattern read by the reading means and the color image information to the color printer. It is characterized by

[Example] Hereinafter, the present invention will be described in detail with reference to the drawings.

FIG. 1 is a block diagram showing an entire embodiment of the present invention. The illustrated image processing device receives character code string signals as shown in FIG. 2 as character image data 101, and R, G, B color identification signals 104 as shown in FIG. , an image signal 105 accompanied by horizontal synchronizing signals 106V, 106H are supplied from the outside. Further, image trimming position designation signals 102, 103, 1
07 and 108 are also supplied from outside.

FIG. 2 shows a character image data string signal, which includes character string data C ₁₀ , C ₁₁ , C _{12 .} . . in the first line following the leading identification code ITOP of one image. Also, a RET code is inserted after the last character of each line. Therefore, when a RET code is detected on the receiving side (that is, on the color recording apparatus side), a line feed is performed. In Figure 2, R ₁
is the RET code for the first line, R ₂ is the RET code for the second line
It is a code. After the last line of the one-character image, the one-character image end code IEND is inserted to mark the end of the one-character image data. This color recording device identifies the end of one character image by receiving this IEND code.

Character image data 101 supplied as described above
is stored in the character code buffer 10 for one screen. At this time, the special code mentioned above (for example,
ITOP code, RET code, IEND code)
It is decoded by the character code decoder 11 and sends out a storage start/line feed command signal 109 and a storage end signal 110 for storing character images.

FIG. 4 shows an example of a character screen stored in this manner. Here, each character A, B,...a,
b, c, . . . are represented by, for example, 8-bit ASCII codes. Since this color recording apparatus employs a laser beam method using dot images, it is necessary to convert the above-mentioned character code string into a dot shape. Therefore, in this embodiment, a character generator 9 is used to perform such dot conversion. The character generator 9 is the same as a well-known one, so a description thereof will be omitted. At this time, an area information signal 102 indicating which area of a single character image supplied from the outside should be printed out (that is, information specifying the row and column of the character code image) is provided from the external device.

For example, in the character code image shown in Figure 4, the printout start character and end character are
When given by m ₁ , n ₁ to m ₂ , n ₂ , the area within the thick line shown in the figure is read out from the character code buffer 10 . Then, upon receiving the printout designation information m ₁ , n ₁ , m ₂ , n ₂ included in the area information signal 102,
A read position designation circuit 17 and a read address generator 18 generate a read address for a designated area.

On the other hand, a designation signal 103 is used to designate which region of the print image the character image region designated as described above should be printed out. The writing area for printout is the pixel number and scanning line number of the writing start position.
m ₁ ′, n ₁ ′, and the same numbers m ₂ ′, n ₂ ′ of the write end position, and the write address to the image memory 8 is given by the image memory write position designation control circuit 15 and the image memory address generator 14. is generated.

The character code image in the specific area read out from the character code buffer 10 in this manner is converted into dot data by the character generator 9, and stored in a designated area in the image memory 8 to be printed out. This situation is shown in FIGS. 5A and 5B.

Next, processing of color halftone images supplied as density data of each color of R, G, and B will be explained. As shown in FIG. 3, this color halftone image includes R, G,
It is composed of a B color identification signal 104, vertical and horizontal synchronization signals 106V and 106H, and density data (ie, image signal) 105 for each pixel of the image. Each color image is stored in a buffer memory 28 for each color according to the R, G, and B color identification signals 104.
1, 28-2, and 28-3, respectively.

Synchronous signals 106V and 106H are supplied to storage address generator 32, and address selector 30 supplies necessary addresses to image buffer memories 28-1, 28-2, and 28-3. Thus, each color image is stored in each of the image buffer memories 28-1, 28-2, and 28-3.

Thereafter, in the same way as reading from the character code buffer 10, an area in which a halftone image is to be printed out is designated by a signal 107 supplied from the outside. This is given as a printout start point, pixel number, and scanning line number, and the addresses of the corresponding image memories 28-1, 28-2, and 28-3 are generated from the read address generator 31.

When reading, the image buffer memory for yellow (stores the B signal) 28-1, the image buffer memory for magenta (stores the G signal) 28-2, and the image buffer memory for cyan (R The same pixels are simultaneously read out as Y, M, and C components from 28-3 (which stores signals). The color signals read out in this way are finally stored in the image memory 21 for halftone images, but as described above, the designated image area is
A signal 108 supplied from an external device (not shown) causes the printout to be printed out at a designated position.
The writing start position is specified. In response to this,
Image memory write position designation circuit 23 and image memory address generator 22 generate an address of image memory 21 corresponding to the designated position. This operation is similar to that for the character image data described above.

In addition, image buffer memory 28-1, 28
The color density data for each pixel read from -2 and 28-3 is subjected to gamma conversion (density conversion) in accordance with the characteristics of this image processing device in the gamma correction circuit 27.
Based on this, we further applied masking processing (see 26) and UCR processing (see 25), which are well known in the printing technology field.
After being subjected to dither processing (see 24), the data is stored as dot data at a specified position in the image memory 21 designated as described above. As is well known, dither processing refers to electrical processing that determines recording dots to be output by comparing the density extension of each pixel with a threshold value in order to reproduce halftones.

This image processing device sequentially prints out a yellow image on the first page, a magenta image on the second page, a cyan image on the third page, and a black image on the fourth page, and then superimposes each color image to create a full color image. Since an image is obtained, the storage capacity of the image memory 21 is sufficient for one image. Then, each time each color is printed, the above-described color processing and transfer to the image memory 21 are performed.

In order to read the data from the character image image memory 8 and the halftone color image image memory 21 and send it to the laser light modulation circuit 5, these image data are stored as dot data in the image memories 8 and 21, respectively, and The same address is assigned to the same pixel.
In this embodiment, both image memories 8 and 2
Addressing of 1 is controlled by an image memory address generator 14. That is, a read address is generated when images are stored in both image memories 8 and 21, and dot data of characters and halftone images corresponding to the same pixel are sent out.

The dot data read from the image memories 8 and 21 are superimposed by the OR gate 7 to modulate the laser beam. The modulated laser light forms an electrostatic latent image on the photosensitive drum 1. The process of creating a print image is similar to that of a normal laser beam printer, and four types of developing units (none of which are shown) are selectively used for Y, M, C, and B _k (black). . Further, a signal 113 is a horizontal synchronizing signal sent from the laser beam detector 40 when the laser beam is irradiated with the laser beam, and causes image data reading from the image memories 8 and 21 to be performed in synchronization.

Note that the signal 112 is a signal for controlling the color of the character image, and causes the image memory 8 to output data only when a desired color is to be printed out. Similarly, when reading a halftone image from the image memory 21, it is also possible to control the reading of only a desired color image to obtain a monochrome or composite color image.

FIG. 5 shows an example in which designated areas of a character image and a halftone image are individually moved, and these two images are combined. That is, the area is moved for each of input images A and C, and the obtained images B and D are combined to create image B+
This will give you D.

As explained above, according to this embodiment, it is possible to synthesize a character image with a halftone image without impairing the sharpness of the character image, and moreover, it is possible to move the designated area for each of the character image and the halftone image separately. Therefore, it is possible to efficiently rearrange and synthesize character images and halftone images.

Further, according to this embodiment, since character images can be input using code codes, connection with other devices is also possible, and a versatile image processing device can be obtained.

Furthermore, according to the present invention, at least one of the halftone image and the line image can be arbitrarily colored, so image processing suitable for office processing after printing (for example, changing the color of characters for each data) is possible. I can do it.

As described above, according to the present invention, colored dot patterns and other color image information can be printed without changing the image formation sequence for each color component of a color printer that sequentially forms images for each color component. Since it can be synthesized, such synthesis can be performed at high speed, and such control can be made simple.

[Brief explanation of the drawing]

FIG. 1 is a configuration diagram showing an entire embodiment of the present invention;
Figure 2 is a diagram showing an example of character image data, Figure 3 is a diagram showing an example of color image data, Figure 4 is a diagram showing an example of a character screen stored in the character code buffer, and Figure 5 is a diagram showing an example of character image data. FIG. 3 is a diagram illustrating an example in which designated areas of a halftone image and a halftone image are moved separately, and the two screens are combined. 1... Photosensitive drum, 2... Lens, 3... Reflection mirror, 4... Laser light source, 5... Laser light modulation circuit, 6... Line buffer, 7... OR gate, 8... Character image memory, 9 ... Character generator, 10 ... Character code buffer, 11 ... Character code decoder, 12 ... Interface, 14 ... Image memory address generator, 15 ... Image memory write position designation circuit, 16 ... Control circuit , 17... Read position designation circuit, 18... Read address generator, 19... Write address generator, 20... Address selector, 21... Image memory for halftone image, 22... Image memory address generator , 23... Image memory write position designation circuit, 24... Dither circuit, 25... UCR circuit, 26... Masking circuit, 27... Gamma correction circuit, 28-1, 28-
2, 28-3...Image buffer memory, 29
...Interface, 30...Address selector, 31...Read address generator, 3
2...Write address generator, 33...
Read position designation circuit, 101 to 113...signal.

Claims (1)

[Scope of Claims] 1. An image processing device for a color printer that sequentially forms an image for each color component for a plurality of color components, wherein the color of the color component is determined according to the image formation operation of each color component in the color printer. a first generating means for generating image information; a memory in which pattern information other than the color image information is stored as a dot pattern; a means for storing a predetermined dot pattern in the memory; and image formation of the dot pattern. a second generating means for generating specification information specifying a color; and coloring the dot pattern according to the specification information without changing the image forming sequence for each color component of the color printer to generate the color image information. reading means capable of reading out the dot pattern stored in the memory at a timing corresponding to the image forming operation of each color component so as to be able to synthesize the image; and the dot pattern and the color image information read out by the reading means. an image processing device, comprising: composition means for outputting a composite signal based on the color printer to the color printer.