JPH0747723A - Digital printer - Google Patents

Abstract

PURPOSE:To prevent excessive labor by subjecting the dot data constituting image data to length and breadth conversion when it is determined that there is length and breadth conversion by a means determining the presence of length and breadth conversion. CONSTITUTION:An error diffusion processing part 70c converts the digital signal of a 8-bit pixel outputted from a CCD part 70a to one bit (binarization) by a method reflecting a binarized error to the binarization judgment of adjacent pixels to perform redistribution operation for faithfully reproducing the local area density of a manuscript. Multivalue processing parts 71a, 71b again convert the data binarized by the error diffusion processing part 70c to 256 gradations and a synthesizing processing part 71c selectively performs logical operation, that is, the operation of OR, AND or exclusive OR at every pixel. A density conversion processing part 71d arbitrarily sets the relation of the output density to input density to the digital signal of 256 gradations on the basis of a predetermined gradation conversion table.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a digital printer for printing out dot data transferred from an information device.

[0002]

2. Description of the Related Art Digital printers such as digital copying machines and laser printers are provided with a plurality of paper cassettes for accommodating papers for forming images, and each paper cassette has papers of different sizes and papers of different feeding directions. Is stored. For example, different size papers such as B5 size paper and A4 size paper, and even A4 size papers with a vertical feed or a horizontal feed are stored. Further, a manual paper tray that can store paper of an arbitrary size and an arbitrary feeding direction is also provided, and at the time of printing, one of a plurality of paper cassettes and a manual paper feed tray is selected for paper feeding.

Here, the case where the short side of the paper is in the feeding direction is called vertical feeding, and the case where the long side is in the feeding direction is called lateral feeding.

Further, when data of information equipment such as a word processor and a microcomputer is printed out by a digital printer, the two are connected by a communication line, and characters or the like are shown by dots from the information equipment side to the printer side. Data such as dot data and size data indicating the size of data and the vertical / horizontal direction are transferred, and information such as the presence or absence of paper is sent from the printer side to the information device side. On the printer side, based on the above size data, the paper cassette or the manual feed tray that stores the paper of the corresponding size and feeding direction is specified, and the paper is fed from the paper cassette or the manual feed tray to print out. It was

Hereinafter, the image data in a printable state on the laterally fed paper will be referred to as horizontal image data, and the image data in a printable state on the vertically fed paper will be referred to as vertical image data.

[0006]

By the way, in a printer having a plurality of paper cassettes as described above, it is common to store papers of different sizes in each of the plurality of paper cassettes. Regarding the size, the feeding direction of the stored sheets is either vertical feeding or horizontal feeding. Therefore, when printing is performed by changing the feeding direction of the paper, it is necessary to set the paper in the manual feed tray at each time, which causes extra labor. Therefore, it is desirable to print in the direction of the size stored in the paper cassette.

However, as described above, when image data is transferred from an external information device for printing, the direction of the image data is determined at the time of transfer, and the paper feed direction is set according to the image data. It was necessary to set the paper in the bypass tray for printing.

Regarding the paper feeding direction, if the paper is fed vertically, the length in the feeding direction is shortened and the printing time can be shortened. However, when the image data is transferred from an external information device and printed. There is also a problem that the print process is slowed down because the paper is often fed horizontally.

Further, depending on the selection of the paper cassette, the print image may not fit on the paper, or the image may be unevenly distributed on the paper and may not look good.

An object of the present invention is to provide a digital printer capable of preventing extra trouble when printing image data transferred from an information device and capable of printing in good quality. To do.

[0011]

According to a first aspect of the present invention, storage means for storing dot data constituting image data sent from an information device such as a word processor, and print processing based on the dot data are performed. In a digital printer provided with a printing unit, means for obtaining the size and direction of image data based on the state of dot data stored in the storage means, and vertical-horizontal conversion according to the obtained size and direction of image data. It is characterized by further comprising: means for determining the presence / absence, and means for performing the vertical / horizontal conversion of the dot data when the presence / absence of the vertical / horizontal conversion is determined by the means for determining the vertical / horizontal conversion.

According to a second aspect of the present invention, in the digital printer according to the first aspect, the means for determining the presence / absence of the vertical / horizontal conversion determines the vertical / horizontal conversion when the image data is in the horizontal direction. It is a means.

According to a third aspect of the present invention, there is provided a digital apparatus comprising a storage means for storing dot data constituting image data sent from an information device such as a word processor, and a printing section for carrying out a printing process based on the dot data. In the printer, a means for determining the size and direction of the image data based on the state of the dot data stored in the storage means, and a size larger than the obtained size of the image data are the size of the printout paper by the printing unit. And means for setting as.

According to a fourth aspect of the present invention, there is provided a digital apparatus including a storage means for storing dot data constituting image data sent from an information device such as a word processor, and a printing section for carrying out a printing process based on the dot data. In the printer, means for determining the size and direction of the image data based on the state of the dot data stored in the storage means, and dot for centering the image data in the size of the paper on which the image data is printed. And means for shifting data.

[0015]

According to the first aspect of the present invention, the size and direction of the image data are obtained based on the state of the dot data forming the image data transferred from the information device such as the word processor, and the obtained image data is obtained. Whether or not vertical / horizontal conversion is performed is determined according to the direction of, and when it is determined that vertical / horizontal conversion is performed, the dot data forming the image data is vertically / horizontally converted. When the dot data is vertically / horizontally converted, the direction of the image data changes. For example, the image data in the horizontal direction becomes the vertical direction. If the direction of the image data can be changed in this way, the image can be printed correctly by changing the direction of the image data without changing the direction of the paper to be printed out. For example, if paper of a size corresponding to the size of the image data is stored in the horizontal feed state and the image data is in the vertical direction, the vertical and horizontal conversion of the image data is performed to bother to set the paper of the vertical feed. You can print without it.

According to the second aspect of the invention, when the image data is in the horizontal direction, the vertical / horizontal conversion is performed. When printing an image, the horizontal feed causes the print speed to be slower than the vertical feed. In the present invention, when the image data is in the horizontal direction, the vertical / horizontal conversion is performed, and the image data is converted in the vertical direction to print.

Therefore, the printing speed becomes higher than that in the lateral feeding state.

According to the third aspect of the present invention, the size of the image data is obtained based on the state of the dot data which constitutes the image data transferred from the information device such as the word processor. Then, a size larger than the obtained size of the image data is set as the size of the printout paper. Therefore, the image data is printed without protruding from the paper.

According to the invention described in claim 4, the size of the image data is obtained based on the state of the dot data constituting the image data transferred from the information device such as the word processor, and the image data is recorded in the paper. Centered. If the size of the image data and the size of the paper on which the image data is printed are known, centering can be performed, and this centering prints the image at the center of the paper in good balance.

[0020]

Embodiments of the present invention will be described below with reference to the drawings.

FIG. 1 is a sectional view showing the overall construction of a digital copying machine which is an embodiment of the digital printer of the present invention.

As shown in the figure, the copying machine main body 30 of this embodiment includes a scanner unit 31, a laser printer unit 32,
A multi-stage paper feeding unit 33 and a sorter 34 are provided.

The scanner unit 31 includes a document placing table 35 made of transparent glass and a double-sided automatic document feeder (RDF) 36.
And a scanner unit 40. RD
In F36, a plurality of originals are set at once, and the originals are automatically fed one by one to the scanner unit 40,
The scanner unit 40 is configured to read one side or both sides of a document according to an operator's selection. The image data obtained by reading the original image with the scanner unit 40 is sent to the image processing unit and subjected to various processes, and then temporarily stored in the memory of the image processing unit.
In response to the output instruction, the image data in the memory is given to the laser printer unit 32 to form an image on the paper. Image data transferred from an information device (word processor, microcomputer, etc.) outside the main body of the copying machine is also stored in this memory, and in that case, the image data of the information device is printed out.

The multi-stage paper feeding unit 33 includes the first cassette 5
It has the 1st, 2nd cassette 52, the 3rd cassette 53, and the 4th cassette 55 which can be added by selection. In the multi-stage paper feeding unit 33, the paper is sent out one by one from the paper stored in the multi-stage cassette and is conveyed toward the laser printer unit 32.

The laser printer unit 32 includes a manual document tray 45, a laser writing unit 46, and an electrophotographic process unit 47 for forming an image. The laser writing unit 46 is a semiconductor laser that emits a laser beam according to the image data from the above-mentioned memory, a polygon mirror that deflects the laser beam at a constant angular velocity, and a laser beam that is deflected at a constant angular velocity is exposed by the electrophotographic process section 47. Body drum 4
8 has an f-θ lens and the like for performing correction so that the light is deflected at a constant speed. The electrophotographic process section 47 comprises a charging device, a developing device, a peeling device, a cleaning device, a discharging device, and a fixing device 49, which are arranged around the photosensitive drum 48 in a known manner.

A conveying path 50 is provided on the downstream side in the conveying direction of the sheet on which the image is to be formed by the fixing device 49.
The transport path 50 branches into a transport path 57 leading to the sorter 34 and a transport path 58 leading to the multi-stage sheet feeding unit 33. The conveyance path 58 is branched in the multi-stage sheet feeding unit 33, and a reversal conveyance path 50a and a double-sided / composite conveyance path 50b are provided as the conveyance paths after branching. The reverse conveyance path 50a is a conveyance path for reversing the front and back sides of a sheet in a double-sided copy mode in which both sides of a document are copied. Both sides /
The composite transport path 50b transports a sheet from the reverse transport path 50a to the image forming position of the photosensitive drum 48 in the double-sided copy mode, or a composite copy in which an image of a different original or an image of a different color toner is formed on one side of the sheet. In the single-sided composite copy mode, in which the sheet is conveyed, it is a conveying path for conveying the sheet to the image forming position of the photosensitive drum 48 without reversing the sheet.

The multi-stage paper feeding unit 33 includes a common conveyance path 56, and the common conveyance path 56 includes the first cassette 51 and the second cassette 51.
The sheets from the cassette 52 and the third cassette 53 are carried out toward the electrophotographic process section 47. The common transport path 56 joins the transport path 59 from the fourth cassette 54 on the way to the electrophotographic process section 47, and communicates with the transport path 60. The conveyance path 60 merges with the conveyance path 61 from the double-sided / composite conveyance path 50b and the manual feed document tray 45 at a confluence point 62 to reach an image forming position between the photosensitive drum 48 of the electrostatic photography process section 47 and the transfer device. The confluence points 62 of these three conveyance paths are provided near the image forming position.

Therefore, in the laser writing unit 46 and the electrophotographic process section 47, the image data read from the above-mentioned memory is stored in the laser writing unit 4.
The toner image formed as an electrostatic latent image on the surface of the photosensitive drum 48 by scanning the laser beam with the toner image visualized by the toner on the surface of the sheet conveyed from the multi-stage sheet feeding unit 33. It is electrostatically transferred and fixed. The sheet on which the image is formed in this way is sent from the fixing device 49 to the sorter 34 via the conveying paths 50 and 57,
It is conveyed to the reverse conveyance path 50a via the conveyance paths 50 and 58.

Next, the configurations and functions of the image processing unit and the image data input / output control unit included in the digital copying machine of this embodiment will be described.

FIG. 2 is a block diagram of an image processing unit and an image data input / output control unit included in the copying machine main body 30 of FIG.

The image processing unit included in the main body 30 of the copying machine includes an image data input unit 70, an image processing unit 71, an image data output unit 72, a memory 73 including a RAM, and a central processing unit for image processing. (Image processing CPU) 74
Is equipped with.

The image data input section 70 is a CCD section 70a,
Histogram processing unit 70b and error diffusion processing unit 70
c is included. The image data input unit 70 is the CCD of FIG.
The image data of the original read from 42 is binarized and converted, and while the histogram is taken as a binary digital amount, the image data is processed by the error diffusion method and stored in the memory 7.
3 is configured to be stored once. That is, C
In the CD 70a, after the analog electric signal corresponding to each pixel density of the image data is A / D converted, MTF correction, black-and-white correction or gamma correction is performed, and a histogram processing unit is generated as a 256-gradation (8-bit) digital signal. It is output to 70b.

In the histogram processing section 70b, the digital signals output from the CCD section 70a are added for each pixel density of 256 gradations to obtain density information (histogram data).
Is obtained, and the obtained histogram data is sent to the image processing CPU 74 or to the error diffusion processing unit 70c as pixel data as required.

In the error diffusion processing unit 70c, the error diffusion method which is a kind of the pseudo center processing unit, that is, the method of reflecting the binarization error in the binarization judgment of the adjacent pixel is output from the CCD unit 70a. A bit / pixel digital signal is converted into 1 bit (binary), and a redistribution operation is performed to faithfully reproduce the local area density in the original.

The image processing unit 71 includes multi-valued processing units 71a and 71b, a synthesis processing unit 71c, a density conversion processing unit 71d,
It includes a scaling processing unit 71e, an image processing unit 71f, an error diffusion processing unit 71g, and a compression processing unit 71h.

The image processing unit 71 is a processing unit for finally converting the image data into image data desired by the operator, and the processing is performed by this processing unit until the converted image data is stored in the memory 73. Is configured. However, each of the above-described processing units included in the image processing unit 71 functions as necessary and may not function. That is, the multi-value quantization processing units 71a and 71b
Then, the data binarized by the error diffusion processing unit 70c is converted into 256 gradations again. In the combination processing unit 71c, a logical operation for each pixel, that is, an operation of a logical sum, a logical product, or an exclusive logical sum is selectively performed. The data that is the target of this calculation is the pixel data stored in the memory 73 and the bit data from the pattern generator (PG).

In the density conversion processing section 71d, the relationship between the input density and the output density is arbitrarily set for the 256 gradation digital signal based on a predetermined gradation conversion table.

In the scaling processing section 71e, pixel data (density value) for the scaled target pixel is obtained by performing interpolation processing with the known data that is input according to the instructed scaling ratio. After the sub scanning is scaled, the main scanning is scaled. The image processing unit 71f performs various image processes on the input pixel data, and collects information on a data string such as feature extraction.
The error diffusion processing unit 71g performs the same processing as the error diffusion processing unit 70c of the image data input unit 70. In the compression processing unit 71h, binary data is compressed by encoding called run length, and regarding compression of image data,
The compression works in the final processing loop when the final output image data is complete.

The image data output unit 72 includes a restoration unit 72a, a multi-value processing unit 72b, an error diffusion processing unit 72c, and a laser output unit 72d.

The image data output unit 72 restores the image data stored in the memory 73 in a compressed state to the original 2
It is configured to convert again 56 gradations, perform error diffusion of 4-valued data that is a smoother halftone expression than binary data, and transfer the data to the laser output unit 72d. That is, the decompression unit 72a decompresses the image data compressed by the compression processing unit 71h. Multi-value processing unit 72
In b, the multivalued processing units 71 a and 7 a of the image processing unit 71.
The same process as 1b is performed. The error diffusion processing unit 72c performs the same processing as the error diffusion processing unit 70c of the image data input unit 70. The laser output unit 72d converts the digital pixel data into a laser on / off signal based on a control signal from the printer control CPU 79, and turns the laser on / off.

The data handled by the image data input section 70 and the image data output section 72 is stored in the memory 73.
The memory 73 is basically stored in the memory 73 in the form of binary data in order to reduce the capacity, but it is also possible to process in the form of four-valued data in consideration of deterioration of image data.

With the above configuration, image processing as a copying machine is performed. On the other hand, image data is transferred from the external information device to the main body of the copying machine, and the image data is printed out. A word processor (word processor) is taken as an example of the information device here. An I / F connector is provided on the side of the operation panel at the top of the copying machine body 30, and is connected to the word processor 21 by a cable line 22 as shown in FIG. In this case, the word processor 21 is placed on the original cover of the copying machine body 30.

The I / F connector is connected to the word processor input / output section 83, and mode setting, dot data, etc. from the word processor are first taken into the word processor input / output section 83. Next, the word processor data control unit 84 determines whether it is communication data for mode setting or the like or image dot data, and when it is communication data for mode setting or the like, it is sent to the printer control CPU 79. The flow of data transmitted from the printer control CPU 79 is the opposite. In the case of image dot data, the data is sent to and stored in the memory 73.

The image processing CPU 74 determines the size of the image data based on the dot data sent from the word processor. FIG. 5 is a diagram for explaining the determination procedure, and a method for determining the image data size (mm) will be described below with reference to the drawing.

In this embodiment, since data is transmitted using an 8-bit cable, data is transferred in 8-dot units. The figure shows the storage state of the memory 73, and the squares show dot data in 8-dot units. The memory 73 includes a page start address storage unit, a print start position address storage unit, a print start position maximum address storage unit, a line feed command address storage unit, a line feed command maximum address storage unit, and a page. A storage unit for the end address is provided. The page start address storage area is the upper edge of the image data, the print start position maximum address storage area is the left edge of the image data, the line feed command maximum address storage area is the right edge of the image data, and the page end address storage area is the image data. For storing the lower end of each.

At the time of data transfer, the word processor first sends the command and address for the print start position, then sequentially sends the dot data with an 8-bit width, and when the dot data for the first line has been sent, returns a line feed. Send a command. On the other hand, when the main body of the copying machine receives the command and address of the print start position, the address of the print start position is first stored in the memory of the page start address of the memory 73, the memory of the address of the print start position, and the print start position. Stored in the storage unit of the maximum address of. Then, the dot data of the first row is sequentially stored in the memory 73. When the line feed command is received, the address at that position is stored in the memory unit of the address of the line feed command and the storage unit of the maximum address of the line feed command in the memory 73.

Next, the address of the print start position of the next line is transmitted from the word processor side, and then the dot data of the next line is sequentially transmitted. The main body of the copying machine clears the storage unit of the address of the print start position of the memory 73, and then stores the address of the print start position of the next line in the storage unit. At the same time, the address is read from the storage unit of the maximum address of the print start position of the memory 73, and the address larger than the address of the print start position of this time (next line) is stored in the storage unit of the maximum address of the print start position. Store again in.

Then, the dot data is sequentially stored in the memory 7
Store in 3. The word processor side transmits a line feed command when the transmission of the dot data of the next line is completed, and the main body of the copying machine clears the address of the line feed command of the previous line and then stores the address of the line feed command of the next line in the memory 73. Stored in the address storage part of the line feed command of. Along with this, the address is read from the memory of the maximum address of the line feed command of the memory 73, the address is compared with the address of the line feed command of this time, and the larger value is set to the maximum address of the line feed command of the memory 73. Is stored again in the storage unit for storing. The maximum address of the line feed command is stored in the memory 73.

Thereafter, similarly, the address of the print start position of the next line, the dot data for one line, and the line feed command are transferred.

After the above processing is repeated, when the main body of the copying machine does not receive dot data for a certain period of time or when a page break command is transmitted, it is judged that the data for one page has been received, The contents of the address of the line feed command at this time are written in the storage unit of the page end address. At this time, based on the addresses stored in the page start address storage section, the print start position maximum address storage section, the page end address storage section, and the line feed command maximum address storage section of the memory 73. The area of the image data is specified and the size of the image data is obtained. In the case of the example shown in FIG. 5, the page start address storage section has an address a in the figure, the print start position maximum address storage section has an address a in the figure, and the page end address storage section has The address of part c in the drawing and the address of part b in the drawing are respectively stored in the storage part of the address of the maximum of the line feed command, and the area of the image data is the part shown by the broken line in the drawing. In this case, size in X direction = (address in X direction of point b) − (address in X direction of point a) size in Y direction = (address in Y direction of point c) − (address in Y direction of point a) ), And the size of the image data (mm) can be calculated by converting the calculated address difference into a length. In this way, the size (mm) of the image data is obtained, and the optimum paper size for printing out the image data is obtained. In this embodiment, B4, B5, A3, A4, and postcard sizes can be processed. Each size is: B4: 257 × 364 mm B5: 182 × 257 mm A3: 297 × 420 mm A4: 210 × 297 mm Postcard : 100 × 147 mm, which is larger than the obtained image data size, and the closest size is obtained as the optimum paper size. For example, when the obtained image data size is 195 × 280 mm, the optimum paper size is A4. After obtaining this size, the image data is processed as A4 size, and "0" is added to the portion other than the dot data of the image (hatched portion in FIG. 5).
Is substituted. In this embodiment, the lower limit of each size is slightly smaller, but the lower limit may be set for each size, and if the size does not fall within the range, it may be set as a special size.

By the way, in this embodiment, B5 size and A4 size papers are accommodated in the paper cassettes 51 and 55 of the copying machine body in a vertically-fed state.
Papers B4 size and A3 size are accommodated in 2, 3 and 5 respectively in a laterally fed state. Printing in the B5 size and the A4 size is performed by vertical feeding, so that the printing speed is increased. On the other hand, the B4 size and the A3 size are in the lateral feed state in consideration of the size of the copying machine body. The postcard is set in the manual feed tray 45 in a vertically fed state. When printing the image data, the dot data forming the image data is vertically and horizontally converted so as to match the above-mentioned state of the paper. FIG. 6 is a diagram showing a table of presence / absence of vertical / horizontal conversion of dot data. This table is a memory 7
3 is stored in advance. Then, based on this table, the presence / absence of vertical / horizontal conversion of dot data is determined. In addition,
The vertical / horizontal conversion of the dot data is performed by once reading the dot data of the image from the memory 73, passing through all the processing of the image processing unit 71 in FIG. 2, and reintroducing the data into the address rotated by 90 °. Done. The address control at the time of this replacement is performed by the image processing CPU 74.

In this example, since the size data is not communicated from the word processor side, the size of the image is recognized based on the dot data sent from the main body of the copying machine, but when the size data is sent from the word processor side. Does not need to recognize the size data on the digital copier body side,
The presence / absence of vertical / horizontal conversion of dot data can be determined based on the sent size data.

Next, an example of processing for printing dot data of a word processor will be described. FIG. 4 is a flowchart showing the processing procedure.

When the print start command is executed on the word processor side, first, the communication check between the word processor 21 and the copying machine main body 30 is performed. In the case of an error, an error is displayed on both the word processor 21 side and the copying machine main body 30 side. Next, the mode setting data indicating that the data is a print of the word processor data is transmitted from the word processor side to the copying machine main body 30 side.
Upon receiving the mode setting data, the copying machine main body sets the mode (n1). If there is any trouble, an error is displayed (n2 → n3).

After the mode setting, the word processor 21 side checks whether or not the copying machine main body 30 side is in the data receivable state, and if it is in the Busy state, the word processor side waits for data transmission until it is released. (N4). If the copier body 30 side can receive data, the dot data for one line is transmitted from the word processor 21 side to the copier body 30 side (n5). When a trouble (power cut, etc.) occurs on the word processor 21 side during transmission, only the data already stored in the memory 73 on the copier body 30 side is printed out. However, the dot data of the page in error is not printed out, but the previous page is printed (n6 → n7 → n8 → n9 or n10). When an error occurs on the copying machine main body 30, only the dot data of the page in error is cleared to the memory, both the copying machine main body 30 and the word processor 21 display a trouble occurrence state, and the standby state is entered. (N11 → n12 → n13).

When the dot data is transferred without any trouble, the data is stored in the memory 73 on the copying machine main body 30 side (n14). After this, the dot data of the next row will be transferred (n4 → n5 ...), but if the data transfer is not performed for a certain period of time (when the copying machine main body 30 side does not receive the data for a certain period of time) or a page break command When it is received, it is considered that all the data of the page is completed, and the size of the image is determined based on the transferred dot data (n15 → n16). Then, based on the above-mentioned determination table (FIG. 6), it is determined whether or not the vertical / horizontal conversion is necessary. If the conversion is not necessary, a paper cassette or a manual feed tray (51, 52) for storing the paper of the corresponding size is determined. , 5
3, 55, 45) is selected.

Selection of the paper cassette is performed as follows. The copying machine main body 30 includes paper cassettes 51, 52, 5
3, 55 and the size and direction of the paper stored in the manual feed tray 45 are input. This is because the paper cassette has markings indicating the size and direction of the paper stored in the paper cassette itself, and the copy machine main body 3
There is a method of inputting by arranging a sensor for reading the marking on the 0 side. Also, the bypass tray 45
In the above, there is a method of inputting the size and direction of the paper by providing a sensor that detects the position of the slidable paper guide and a sensor such as a micro switch that turns on / off when the paper is placed. is there. Based on the paper size and orientation entered in this way,
Select the paper cassette or bypass tray to feed.

On the other hand, the above-mentioned judgment table (FIG. 6)
If it is determined that the vertical / horizontal conversion is required, the dot data is vertically / horizontally converted. After that, if all pages are finished, printout processing and memory 73 after printout are cleared (n19 → n20).

In this embodiment, the paper cassettes 51, 52, 53, 55 of the copying machine body and the manual feed tray 45 are used.
The orientation of the paper to be stored in the paper is determined in advance in a predetermined direction. If this is not determined, the paper is stored in the paper cassettes 51, 52, 53, 55 and the manual feed tray 45 read by the copying machine body itself. It may be determined whether or not there is a printable size paper based on the size of the paper. At this time, if a printable size of paper is not stored, a message to that effect is displayed. Also, if printable size paper is stored in any of the paper cassettes or bypass trays, determine whether the feed direction of that size paper matches the image data, If so, select that paper cassette or manual feed tray to print out, and if they do not match, rotate the image data 90 ° as described above, then select that paper cassette or manual feed tray. Print out.

If the image data input from an information device such as a word processor is not located at the center of the paper, the image data may be centered.
For centering the image data, a key for designating the setting of the function is provided on the word processor side or the copying machine main body side. And when the centering function is set,
The data stored in the memory 73 is centered on the copying machine main body 30 side.

In the centering, as shown in FIG. 7A, the determined paper size is converted into the number of pixels (the number of dots) in each of the X direction (horizontal direction) and the Y direction (vertical direction), and the memory is stored. The number of dots in the data stored in is subtracted, a value of 1/2 of that number is obtained and set as the address of the print start position, and based on this, the dots in the memory 73 are set as shown in FIG. 7B. The data is shifted and stored again in the memory 73.

A specific example is shown below. Note that the paper size in this case, whether it is determined based on the size of image data as described above or data transferred from the information device side, is input by a key or the like on the copier body side. It may be

Now, it is assumed that the number of pixels of paper and the number of pixels of image data are as follows. Number of pixels of paper in X direction: 3307 Number of pixels of paper in Y direction: 4677 Address of left end (point a) of image data in X direction: 00C8 Same number of pixels: 200 Number of top end of image data in Y direction (point a) Address: 012C Same number of pixels: 300 Address of right end (point b) of image data in X direction: 0A8C Same number of pixels: 2700 Address of lower end of image data in Y direction (point c): 0BB8 Same number of pixels: 3000 The address (X, Y) of the print start position a'when centering is as follows.

Address of print start position in X direction {3307- (2700-200)} / 2 = 703 = 0
2BF Address of print start position in Y direction {4677- (3000-300)} / 2 ≈ 988 = 0
3DC That is, the address (X, Y) of the print start position a '=
(02BF, 03DC). Therefore, centering is performed by shifting the point a to the point a'and shifting the entire image data with reference to this point (FIG. 7).
(See (B)).

After performing the centering process as described above,
A centered print image can be formed by executing printout.

In this embodiment, the dot data size and direction are obtained by storing the dot data address when a line feed command is received, but other methods may be used. For example, count and store the number of dots,
The size and direction of the image data may be obtained based on the number of dots.

[0067]

According to the invention as set forth in claim 1, the size and direction of image data input from an information device such as a word processor is obtained, and if the direction is a predetermined direction, the image data is Since the constituent dot data is vertically / horizontally converted, it becomes possible to match the direction of the image data with the direction of the paper to be printed out, and it is possible to eliminate the need to set the paper according to the image data.

According to the second aspect of the present invention, when the image data is in the horizontal feed state, the vertical / horizontal conversion is performed to put the image data in the vertical feed state, and the image data in the vertical feed state is printed out. Therefore, the print time can be shortened as compared with the printout in the horizontal feed state.

According to the third aspect of the invention, according to the size of the image data, a sheet of a size larger than the size of the image data is set and printing is performed.
It is possible to obtain a high-quality print image without the image protruding from the paper.

According to the invention described in claim 4, since the image data is centered in the paper, it is possible to obtain a well-balanced and high-quality print image.

[Brief description of drawings]

FIG. 1 is a sectional view showing the overall configuration of a digital copying machine.

FIG. 2 is a block configuration diagram of an image processing unit and a control unit of the digital copying machine.

FIG. 3 is a diagram showing an example of a connection state between the digital copying machine and a word processor.

FIG. 4 is a flowchart showing a procedure of image data transfer and size determination processing.

FIG. 5 is a diagram for explaining a size determination procedure of image data.

FIG. 6 is a diagram showing a state of determining whether image data is vertically / horizontally converted.

FIG. 7 is a diagram for explaining a centering processing procedure of image data.

Claims (4)

[Claims] 1. A digital printer comprising: a storage unit that stores dot data that constitutes image data sent from an information device such as a word processor; and a printing unit that performs a printing process based on the dot data. Based on the state of the dot data to be stored, means for obtaining the size and direction of the image data, means for determining the presence or absence of vertical and horizontal conversion according to the obtained size and direction of the image data, the presence or absence of the vertical and horizontal conversion A digital printer, comprising: means for vertically / horizontally converting the dot data when it is determined by the means for vertically / horizontal conversion. 2. The digital printer according to claim 1, wherein the means for determining the presence / absence of vertical / horizontal conversion is means for determining the presence / absence of vertical / horizontal conversion when the image data is in the horizontal direction. 3. A digital printer comprising: a storage unit for storing dot data constituting image data sent from an information device such as a word processor; and a printing unit for performing a printing process based on the dot data. Means for obtaining the size and direction of the image data based on the state of the stored dot data; and means for setting a size larger than the obtained image data size as the size of the printout paper by the printing unit. A digital printer characterized by being provided. 4. A digital printer comprising: a storage unit for storing dot data constituting image data sent from an information device such as a word processor; and a printing unit for performing a printing process on the basis of the dot data. Means for determining the size and direction of the image data based on the state of the stored dot data; means for shifting the dot data to center the image data during the size of the paper on which the image data is printed; A digital printer characterized by having.