JPH06245055A - Device and method for printing - Google Patents

Abstract

PURPOSE:To thin a small picture element obtained by means of dividing a picture element and to make reduction printing possible without the perfect omission of the original original picture element by printing an original picture with the picture elements the number of which is smaller than the (n) specified small elements. CONSTITUTION:A reduction control part 1 successively converts the picture element P of picture data which is serially inputted into the small picture elements p consisting of the eight prescribed picture elements and outputs them to a page printer part 3 (LBP part) as a signal PRINTDT. An oscillator 2 is a clock oscillator stipulating the printing dot width of the small picture elements p and its clock cycle is decided by the main scanning speed of the page printer part 3. Thus, one picture element of the received original printing picture is divided into the eight small picture elements having 1/8 width and the small picture elements are thinned in accordance with a reduction rate so as to execute printing so that reduction printing in a main scanning direction is made possible without the perfect omission of the original picture element only by using a single clock oscillating source.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a printing apparatus and method for thinning pixels to perform reduced printing.

[0002]

2. Description of the Related Art In a conventional facsimile machine, a cut sheet of a fixed length is mainly used as a recording sheet, and a received image received as a facsimile is a header for displaying an ID of the sender side as well as an original image. Parts are added. For this reason, when the received image is printed at the same size, a part of the received image protrudes from the recording paper having the standard length for one page, and the received image must be divided into two pages.

Therefore, in order to avoid such divided printing, a method is adopted in which the received image length and the recording paper length are compared and a predetermined reduction is performed for printing. In this case, with respect to the sub-scanning, reduction processing is performed by thinning out lines for each predetermined amount. In addition, in the main scanning, the same reduction as in the sub-scan is performed. (1) Thinning processing of received pixels (2) To reduce the irradiation time of the laser light per pixel in the page printer, the print image of the printed image is reduced. A method such as speeding up the output clock by a predetermined amount is used.

Further, in the conventional facsimile apparatus, in the case of printing with a page printer, when printing is performed with a beam spot having the same width as the original pixel, the spot is a large dot when actually transferred onto the recording paper with toner. There is a characteristic that becomes. Therefore, there is a method in which an original pixel is once converted into a predetermined n small pixel patterns so that the dots have a width equal to or smaller than the width of the original pixel according to the surrounding pixels, and then printing is performed. Has been.

[0005]

However, in the above-mentioned conventional facsimile apparatus, when the method of thinning out the received pixels is adopted, the received pixels are completely missing at a predetermined cycle, so that the image quality is deteriorated. There's a problem. Also, when the method of increasing the output clock of the print image by a predetermined amount is adopted, a clock oscillation source dedicated for reduction is required in addition to the case of equal magnification, and further, the reduction ratio that can be provided as an apparatus becomes plural. Since a plurality of clock oscillation sources corresponding to the respective reduction rates are required, there is a problem that the device becomes complicated and expensive.

An object of the present invention is to provide a printing apparatus and method capable of thinning out small pixels obtained by dividing pixels and performing reduced printing without complete omission of original pixels.

[0007]

In order to achieve the above-mentioned object, the invention according to claim 1 has a pixel width of 1 / n (n is an integer) of one pixel constituting an original image. In the printing apparatus for printing the image by converting it to n small pixels having, a means for creating a pixel pattern in which data of a predetermined bit is associated with the n small pixels, and a reduction ratio of the original image. Based on the above, a means for thinning out the bits forming the pixel pattern is provided, and the original image is printed with a number of pixels smaller than the n small pixels.

According to the invention of claim 3, one pixel forming the original image is converted into n small pixels having a pixel width of 1 / n (n is an integer) of the one pixel, and the pixel is converted into n small pixels. In a printing device for printing an image, a unit for creating a pixel pattern in which a predetermined bit of data is associated with the n small pixels, and a unit for thinning out a predetermined number of bits forming the pixel pattern are provided. The original image is printed with a smaller number of pixels than n small pixels.

[0009]

With the above arrangement, the original pixel is prevented from being completely lost even when the pixel thinning process is performed in the reduction printing.

[0010]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Preferred embodiments of the present invention will be described in detail below with reference to the accompanying drawings. FIG. 1 is a block diagram showing a configuration of a print control unit of a facsimile machine (hereinafter referred to as a system) according to an embodiment of the present invention. In the print control unit shown in the figure, an image is printed by a page printer (hereinafter referred to as LBP) using a page memory described later.

In FIG. 1, reference numeral 1 is a main scanning reduction controller for converting a pixel P into n small pixels p, and 2 is a small pixel p.
An oscillator that generates a clock that defines the print dot width of the
Reference numeral 3 denotes a page printer unit that inputs a video signal and prints the video signal. Reference numeral 4 denotes a page memory that stores pixels P of one page of a print image. Reference numeral 5 denotes input / output of image data to / from the page memory 4. The page memory control unit that controls and 6
A system control unit that controls the entire system.

In this system, the image data to be printed is
First, the system controller 6 writes the page memory controller 5. The page memory control unit 5 sequentially stores the written image data in the page memory 4. When the image data corresponding to one page of the recording paper has been stored in the page memory 4 in this way, the system control unit 6 switches the page memory control unit 5 to the read mode and starts printing the image.

The page memory control unit 5 controls the print start timing with the page printer unit 3. Here, the page printer control unit 5 activates the reduction control unit 1 by outputting a signal STRT each time printing is started in the main scanning direction. Further, the parallel image data from the page memory 4 is input to the page memory control unit 5, converted into serial data by the parallel-serial conversion unit (see FIG. 4) in the page memory control unit 5, and then the reduction control unit 1 In synchronization with the shift clock PIXCK from
It is output to the reduction controller 1.

The reduction control unit 1 sequentially converts the pixels P of the serially input image data into small pixels p of predetermined 8 pixels, and the page printer unit 3 receives the signal PRI.
Output as NTDT. The oscillator 2 is a small pixel p
Is a clock oscillator that regulates the print dot width of, and its clock period is determined by the main scanning speed of the page printer unit 3.

2 and 3 are block diagrams showing the detailed construction of the main scanning reduction control unit 1 which constitutes the printing control unit shown in FIG. In FIG. 2, reference numeral 11A is a 4-bit register that stores a setting value that determines the reduction ratio in the main scanning direction, 1
When the pixel P is a black pixel, reference numerals 02 to 105 store a conversion pattern for converting into eight small pixels p in accordance with the colors of the pixels on the left and right of the pixel in a method described later. The registers 10A, 10B, and 10C are a pixel to be converted (10B) and pixels to the left and right thereof (10A, 10B)
It is a DF / F that stores C). Further, 10F is a 4to1 selector that selects one data from the conversion pattern 4 input data.

In FIG. 3, reference numeral 306 is a 4-bit synchronous counter for counting the reduction ratio in the main scanning reduction control unit 1.
Reference numerals 318 and 319 denote the 4to1 selector 10F shown in FIG.
It is a shift register for parallel loading the pattern data of the small pixel p selected in. FIG. 4 is a block diagram showing a detailed configuration of the page memory control unit 5 shown in FIG. As shown in the figure, the page memory control unit 5 is mainly composed of a control unit 55, and includes an address generation unit 51, a data input / output buffer 52, a latch 53, and a parallel-serial conversion unit 54. In the page memory controller 5, the address according to the control data from the controller 55 is output from the address generator 51 to the page memory 4. As a result, predetermined data is input from the page memory 4 to the parallel-serial conversion unit 54, so that the parallel-serial conversion unit 54 converts the parallel image data from the page memory 4 into serial data as described above. To be converted.

FIG. 5 is a timing chart showing the operation at the same size printing in the system according to this embodiment. In the system according to the present embodiment, since the original pixel P is converted into eight small pixels p and printed as described above, the black pixel of interest is obtained from the combination of the colors of the left and right pixels thereof.
Set to convert as follows.

Left pixel Right pixel Small pixel p pattern White White 00001111 White Black 00011111 Black White 00111111 Black Black 01111111 (p0) (p7) In the timing chart shown in FIG.
4 ”is DATA7,6,5,4 output from the system control unit 6.
Is a hexadecimal display (MSB = DATA7), and "D3210" is
It is a hexadecimal representation of DATA3,2,1,0 (MSB = DATA3). Also,
318 # Q and 319 # Q are shift registers 318 and 31 respectively.
Hexadecimal display of data output in parallel from 9 (MSB = QA
Terminal), 318 # IN, 319 # IN are shift register 3 respectively
The parallel input to 18, 319 is displayed in hexadecimal (MSB = PA terminal).

In the period T0, the conversion pattern and the main scanning reduction rate are set. Here, since the operation start signal STRT becomes logic "1", the 4-bit synchronous counter 306 repeatedly starts counting from 8 to F. In the period T2, the conversion target pixel (DF /
Since the output 10B # Q of F10B becomes logic "1",
Since the output 10H # X of the AND gate 10H also becomes a logic "1", the output from the 4to1 selector 10F, that is, the content of the 8-bit register 102 is output to PDT-0: 7. Then, in the period T3, the output P from the 4to1 selector 10F is input to the shift registers 318 and 319.
DT-0: 7 is loaded, and the small pixel p of 8 pixels is D
The print output data PRNTDT is sequentially output via the F / F 313.

Hereinafter, similarly, the periods T5, T6, T7, T
In FIG. 10, the small pixel pattern set in the 8-bit register is output in the same size corresponding to the original pixel P.
FIG. 6 is a timing chart in the case where the system according to the present embodiment is operated by changing the reduction ratio setting from the same size to 7/8 reduction. In this case, the 4-bit synchronous counter 30
6 repeats counting from 9 to F, and the pattern of the small pixels p for each original pixel outputs only 7 pixels from p0 to p6. This is the period T3, T
5, T6, T7, T10, T11. Needless to say, seven small pixels are output even during the white pixel period. In addition, in FIG. 11, the system according to the present embodiment is
FIG. 7 shows a print result when the operation is performed according to the timing charts shown in FIGS. 5 and 6. FIG. As is clear from the figure, the small pixel p7 is omitted during the 7/8 reduction.

As described above, according to this embodiment,
1 pixel of the received original print image
By dividing into 8 small pixels of width and thinning out these small pixels according to the reduction ratio before printing, only a single clock oscillation source is used and the original pixels are not completely lost. It is possible to perform reduced printing in the main scanning direction. Further, since reduction printing can be performed only by providing a single clock oscillation source, the cost of the device can be reduced. <Other Embodiments> Other embodiments of the present invention will be described below.

In the system according to the above-described embodiment, the method of thinning out the predetermined small pixels p for each original pixel P is adopted, but in this method, the pattern of the print pixels after reduction becomes the set value. However, there are few types of reduction rates that can be selected. Therefore, as another embodiment of the present invention, a method of thinning out the small pixels p by a predetermined number will be described.

FIG. 7 and FIG. 8 are block diagrams showing the detailed structure of the main scanning reduction control section which constitutes the print control section of the facsimile apparatus according to another embodiment. Since a part of the main-scanning reduction control unit according to the present embodiment has the same configuration as the main-scanning reduction control unit according to the above-described embodiment shown in FIG. 2,
Here, illustration and description thereof are omitted. In FIG. 7, reference numeral 202 is a reload binary synchronization counter for detecting the small pixel p to be thinned out, and 21X, 20D
Is a parallel-loadable shift register for creating a timing for loading the converted small pixel pattern into the shift register, and reference numerals 216, 206, 201, 20.
K, 220, 221, 222, 223 are selectors for equivalently shifting the contents of the shift registers 21X, 20D by 2 bits in 1 clock.

In FIG. 8, reference numerals 218 and 219 denote parallel loadable shift registers for parallel-serial conversion of small pixel patterns, and 214 and 203-2.
05, 20A, 20B, 20C and 20F equivalently shift the contents of the shift registers 218 and 219 by 2 bits in one clock, or load the small pixel pattern as it is, or the small pixel pattern. Is loaded in a form of being shifted by one pixel, and is a selector for selecting any one of.

FIG. 9 is an operation timing chart at the same magnification in this embodiment, and FIG. 10 is an operation timing chart at the time of 6/7 reduction. 9 and 10, "RDCEN" is a signal for permitting main scanning reduction operation, "D7654" is DATA7,6,5,4 shown in hexadecimal notation (MSB = DATA7), Also, "D3210"
Is a hexadecimal representation of DATA3,2,1,0 (MSB = DATA3). Then, 218 # Q and 219 # Q display the outputs from the respective shift registers 218 and 219 in hexadecimal notation (MSB = QA terminal), and 218 # IN and 219 # IN respectively output to the shift registers 218 and 219. Parallel input is displayed in hexadecimal (MSB = PA terminal).

In thinning out the small pixel p in this embodiment, the next small pixel after the counter 202 has counted "F" is thinned out. The setting values of the small pixel pattern in FIG. 10 are the same as those in the above-described embodiment, the small pixels p3 are thinned out during the period T3, and the two small pixels p0 and p7 are thinned out during the period T6. Be drawn. Then, in order to thin out one small pixel every time 6 small pixels p are output over the entire period, the shift registers 21X, 20D, 21
Select the reload data by controlling the selectors located in the respective parallel load input sections so that the contents of 8 and 219 are shifted by 2 bits.

FIG. 12 shows an array of print pixels in the facsimile apparatus according to this embodiment. Unlike the above embodiment, the value of n of thinned-out small pixels p (n) is not constant. I won't. In this embodiment, the range of selection of the reduction ratio can be expanded as described above. The present invention is
It may be applied to a system composed of a plurality of devices or an apparatus composed of a single device. Further, the present invention is
It goes without saying that the present invention can also be applied to the case where it is achieved by supplying a program to a system or apparatus.

[0028]

As described above, according to the present invention,
By thinning out the small pixels formed by dividing the pixels based on the reduction ratio of the original image, reduction printing can be performed without completely missing the original pixel. Further, since it is possible to print a plurality of reduced widths with a single clock oscillation source, the cost of the apparatus can be reduced.

[Brief description of drawings]

FIG. 1 is a block diagram illustrating a configuration of a print control unit of a facsimile machine according to an exemplary embodiment of the present invention.

FIG. 2 is a block diagram showing a detailed configuration of a main scanning reduction control unit 1 which constitutes a print control unit.

FIG. 3 is a block diagram showing a detailed configuration of a main scanning reduction control unit 1 which constitutes a print control unit.

FIG. 4 is a block diagram showing a detailed configuration of a page memory control unit 5.

FIG. 5 is a timing chart showing an operation during equal-magnification printing in the system according to the embodiment.

FIG. 6 is a timing chart when the reduction ratio setting is changed from 1: 1 to 7/8 reduction and the system is operated in the system according to the embodiment.

FIG. 7 is a block diagram showing a detailed configuration of a main-scanning reduction control unit that constitutes a print control unit of a facsimile apparatus according to another embodiment.

FIG. 8 is a block diagram showing a detailed configuration of a main scanning reduction control unit that constitutes a print control unit of a facsimile apparatus according to another embodiment.

FIG. 9 is an operation timing chart at the same magnification in another embodiment.

FIG. 10 is an operation timing chart at the time of 6/7 reduction in another example.

FIG. 11 is a diagram showing a printing result by the system according to the embodiment.

FIG. 12 is a diagram showing an arrangement of print pixels in a facsimile apparatus according to another embodiment.

[Explanation of symbols]

 1 main scanning reduction control unit 2 oscillator 3 page printer unit 4 page memory 5 page memory control unit 6 system control unit 11A 4 bit register 102-105 8 bit register 10A, 10B, 10C D-F / F 10F 4to1 selector 306 4 bit Synchronous counter 318,319 Parallel load shift register

Claims (6)

[Claims] 1. A printing apparatus for printing an image by converting one pixel forming an original image into n small pixels having a pixel width of 1 / n (n is an integer) of the one pixel, and printing the image. and a means for creating a pixel pattern in which a predetermined bit of data is associated with n small pixels, and a means for thinning out the bits forming the pixel pattern based on the reduction rate of the original image. A printing apparatus, wherein the original image is printed with a smaller number of pixels than small pixels. 2. The printer according to claim 1, wherein the pixel pattern is created by associating n-bit data with the n small pixels. 3. A printing apparatus for converting one pixel constituting an original image into n small pixels having a pixel width of 1 / n (n is an integer) of the one pixel and printing the image, A unit for creating a pixel pattern in which a predetermined bit of data is associated with n small pixels, and a unit for thinning out the bits forming the pixel pattern every predetermined number, and a number smaller than the n small pixels is provided. A printing apparatus, wherein the original image is printed by the pixels of. 4. The printing apparatus according to claim 3, wherein the pixel pattern is created by associating n-bit data with the n small pixels. 5. A printing method in which one pixel forming an original image is converted into n small pixels having a pixel width of 1 / n (n is an integer) of the one pixel and the image is printed, The method comprises the steps of creating a pixel pattern in which n small pixels are associated with predetermined bits of data, and thinning out the bits forming the pixel pattern based on the reduction ratio of the original image. A printing method, wherein the original image is printed with a smaller number of pixels than small pixels. 6. A printing method for converting one pixel forming an original image into n small pixels having a pixel width of 1 / n (n is an integer) of the one pixel and printing the image, a step of creating a pixel pattern in which a predetermined bit of data is associated with n small pixels, and a step of thinning out the bits forming the pixel pattern for every predetermined number, and a number smaller than the n small pixels A method of printing, wherein the original image is printed with the pixels.