JPH04296577A - Image recording device - Google Patents

Abstract

PURPOSE:To provide an image recording device capable of recording a high- quality image by enabling a memory capacity to be maintained to a minimum level and nevertheless, even a remote area to be monitored. CONSTITUTION:Binary bit map data 500 are sequentially transferred from a controller in an unillustrated host computer or printer and then are stored in a monitor part 200 and a line memory part 100. Data 600 stored in the monitor part 200 are entered in a lookup table 300, then highlighted pixels are split in a scan and a subscan direction based on pixel data in the periphery and these split pixels are output to a memory part 400. Finally an image is recorded using an unillustrated printer.

Description

[Detailed description of the invention]

0001

FIELD OF INDUSTRIAL APPLICATION The present invention relates to an image recording device, and particularly to an image recording device, which stores pixel data in both main scanning and sub-scanning directions, and performs data interpolation of a pixel of interest based on the stored pixel data.
The present invention relates to an image recording device that records images.

0002

2. Description of the Related Art Conventionally, a laser beam printer is an example of this type of device. And the resolution of laser beam printers is usually 300 or 400
dpi (dots per inch) is the mainstream.

0003

[Problems to be Solved by the Invention] However, in simple zero-order interpolation, which processes a 2x2 or 3x3 pixel set as a unit and improves the resolution by two or three times, the memory capacity also quadruples. , 9 times, which makes it very expensive. Therefore, various methods have been proposed for optimizing while monitoring surrounding pixels, but these also have various limitations.For example, expanding the monitoring area slows down the processing speed,
Moreover, since the circuit is large-scale, it has the disadvantage of being expensive.

The present invention has been made to solve the above problems, and provides an image recording device that can record high-quality images by monitoring a more distant area with a minimum memory capacity. The purpose is to

[0005]

Means for Solving the Problems and Operations In order to achieve the above object, an image recording apparatus of the present invention has the following configuration.

That is, this is an image recording device that stores pixel data in both the main scanning and sub-scanning directions, performs data interpolation for a pixel of interest based on the stored pixel data, and records an image. A storage means for storing data in both the scanning and sub-scanning directions, a reference means for referencing predetermined pixel data stored in the storage means, and a pixel of interest in the main-scanning and sub-scanning directions based on the pixel data from the reference means. It has a dividing means for dividing into both parts, and a recording means for recording according to the data divided by the dividing means.

[0007] Further, an image recording apparatus according to another invention has the following configuration. That is, it is an image recording device that stores pixel data in both the main scanning and sub-scanning directions, performs data interpolation for the pixel of interest based on the stored pixel data, and records an image. a storage means for storing data in both scanning directions; a first reference means for referring to predetermined pixel data stored in the storage means; A dividing means for dividing in both sub-scanning directions, a second reference means for referring to the data divided by the dividing means, and a determining means for determining a center pixel based on the data from the second reference means. has.

[0008]

DESCRIPTION OF THE PREFERRED EMBODIMENTS A preferred embodiment of the present invention will be described in detail below with reference to the drawings.

[0009] In the following, we will discuss a laser beam printer that inputs binarized pixel data and records an image by exposing a photoreceptor to a beam light modulated by the pixel data whose resolution has been improved by data interpolation. The data interpolation processing section will be explained in detail. <First Embodiment> FIG. 1 is a schematic block diagram showing the configuration of a data interpolation processing section in a first embodiment. In the figure,
Reference numeral 500 denotes an input, which is bit map data that is binarized for use in the printer by a host computer (not shown) or a controller unit in the printer. A monitoring unit 200 monitors the input binary data 500 within a predetermined interval. Then, data 600 from the monitoring unit 200
is stored in the line memory unit 100, and the data 700 from the line memory unit 100 is input again to the monitoring unit 200, and as a whole, binary data is stored within a predetermined interval in both the main scanning and sub-scanning directions. . A look-up table (LUT) 300 receives data 600 from the monitoring unit 200 as an address and outputs predetermined data 800 corresponding to the address. And 400
1 is a memory unit which inputs data 800 from the LUT 300 and outputs data 900 converted into raster form to a printer mechanism unit (not shown).

FIG. 2 is a diagram showing the data arrangement of the monitoring section 200 in the first embodiment, and FIGS. 4 to 6 are diagrams showing the configuration of the monitoring section 200. Each of the data shown in FIG. 2 is stored in each of the 1-bit flip-flops 201 to 289 shown in FIGS. 4 to 6.

FIG. 3 is a diagram showing details of the line memory section 100 in the first embodiment, which is composed of an 8-bit input/8-bit output FIFO.

FIG. 7 shows a look up table 300
, each pixel data from the monitoring unit 200 is used as an address, and a predetermined pattern corresponding to the address is output, thereby outputting a signal 800 in which the pixel of interest is divided into two in both main scanning and sub-scanning directions. do.

FIG. 8 is a diagram showing a detailed configuration of the memory section 400. In the figure, 411 and 412 are 2-bit inputs/2
FIFOs for bit output, 421 and 422 are shift registers, 423 is a toggle flip-flop, and the input signal 800 is converted into a raster format in accordance with the printer of the output device.

The operation of the first embodiment having the above configuration will be explained in detail below.

Binarized bit map data from a host computer (not shown) or a controller in the printer is sent to the register 20 of the monitoring unit 200 shown in FIGS. 4 to 6.
1 to 209 and stored sequentially. Further, the word length of the line memory section 100 shown in FIG. 3 has the data length of one line in the bit map data to be transferred. Therefore, data for eight lines is stored in total. The output 610 from the register 209 in FIG. 6 is input to and stored in the first bit of the line memory section 100. Then, in order to monitor the data of the second line, memory 1
The output 710 from 00 is input to the register 211 in FIG. 4, and is sequentially transferred and stored in each register 211-219. Similarly, the output 620 from the register 219
is input to the 2nd bit of the line memory section 100, and
The data is stored as line data. Similarly, 3
Data from the 9th line to the 9th line are stored respectively.

As a result, data for a total of 81 pixels (9 lines x 9 dots) is stored in the monitoring section 200, as shown in FIG. Here, if the pixel at the location indicated by an * mark is the pixel of interest D55, the monitoring unit 200 sets the pixel four lines before the line where the pixel of interest is located as the first line, and sequentially descends to the ninth line. A monitoring area is constructed with a certain item as the 9th line. Then, each pixel of the pixel of interest D55 in the monitoring area is accessed line by line and input to the look-up table 300. That is, the 1st, 3rd, and 5th lines (the line of the pixel of interest D55), the 1st, 3rd, 5th pixels (the pixel of interest D55), and the 7th pixels of the 7th and 9th lines, respectively. , only the ninth pixel is output.

Then, a predetermined pattern forming an optimal dot arrangement according to the dot distribution around the pixel of interest D55 is output from the look-up table 300. That is, as shown in FIG. 11, the pixel of interest D55 is divided into data a to d obtained by dividing one pixel into two in both main scanning and sub-scanning.
is interpolated data 800a, 800b, 800
c, 800d is output.

Next, the interpolated data 800a and 800b are stored in the FIFO 411 shown in FIG.
Data 800c and 800d are respectively written in . Here, each FIFO 411, 412 has a capacity that can store two lines of 2-bit data. Reading from each FIFO 411, 412 is performed using a clock 2CLK, which is twice the clock CLK during writing, and at the same time, each data 810a, 810b, 810c, 810d is loaded into each shift register 421, 422, respectively.

That is, a and b shown in FIG.
10a and 810b, respectively, and shift register 4
21. Furthermore, c and d are signals 810c and 810c.
10d and are loaded into the shift register 422. Although not shown, when a counter that counts the number of pixels in the main scanning direction counts the number of pixels for one line, a carry occurs and is input to the toggle flip-flop 423 in FIG. Now, when operation begins, toggle flip-flop 423 is reset and FIFO 411 and shift register 421 are enabled. Then, the data is read out at 2CLK, which is twice the speed of the write clock CLK to the FIFO 411, and sent out from the shift register at 4CLK, which is four times the speed. In other words, the signals are output in the order of a and b shown in FIG. 11, and this repetition is performed for one line. When finished, the HCNT signal is input to the toggle flip-flop 423 and the state is inverted. As a result, this time FI
The FO 412 and shift register 422 are enabled, and c and d shown in FIG. 11 are repeatedly output in the same manner as the above-described operation.

By the data interpolation process described above, the original image shown in FIG. 9 is data-interpolated, converted into a smooth image as shown in FIG. 10, and recorded.

As explained above, according to the first embodiment, by making the data monitoring area every n lines and n pixels, it is possible to quickly detect and improve trends further away, and the amount of data is small. This has the effect of reducing the capacity of the look-up table. <Second Embodiment> Next, a second embodiment of the present invention will be described in detail with reference to the drawings.

In the first embodiment, processing was performed in one monitoring area (window), but in the second embodiment,
Furthermore, by connecting monitoring windows in multiple stages, more detailed processing can be performed.

FIG. 12 is a schematic block diagram showing the configuration of the data interpolation processing section in the second embodiment. In the figure, 5
00 is an input, which is bit map data that has been binarized for the printer by a host computer (not shown) or a controller unit in the printer. 200 is a monitoring unit, which monitors the input binary data 500 within a predetermined interval;
Monitor. Then, the data 600 from the monitoring section 200 is stored in the line memory section 100, and the data 700 from the line memory section 100 is inputted again to the monitoring section 200, and the entire data is stored in a predetermined section in both the main scanning and sub-scanning directions. Of these, binary data is stored. Reference numeral 300 denotes a look-up table, which inputs data 600 from the monitoring section 200 as an address, outputs predetermined data 800 corresponding to the address, and feeds it back to the monitoring section 200. 400 is a second
The signal 600 from the monitoring unit 200 is input as an address, and a predetermined signal 90 is input as a look-up table.
0 is output as a processing result to a printer (not shown).

FIG. 13 shows the monitoring unit 200 in the second embodiment.
16 and 17 are diagrams showing the configuration of the monitoring unit 200. FIG. Each data shown in FIG. 13 is stored in the 1-bit flip-flops 201-223 and the 4-bit flip-flops 224-245, respectively.

FIG. 14 shows a data array of the second monitoring section configured in multiple stages, which also serves as a part of the monitoring section 200 shown in FIG. That is, d of D33 shown in FIG.
Pixels, c and d pixels of D34 and D35, b and d pixels of D43 and D53, and a to d of D44, D45, D54 and D55
It is a pixel.

FIG. 15 is a diagram showing details of the line memory section 100 in the second embodiment, and shows the details of the line memory section 100 in the second embodiment.
It consists of a bit output FIFO.

FIG. 18 is a diagram showing a look-up table, in which each pixel data from the monitoring section 200 is input as an address, a predetermined pattern corresponding to the address is output, and the pixel of interest is scanned in the main scan direction. The signal is fed back to the monitoring unit 200 as a signal 800 divided into two in both sub-scanning directions.

FIG. 19 is a diagram showing the second look-up table 400. 410 inputs each pixel data as an address, outputs a predetermined pattern according to the address, and displays the "white" of the pixel of interest. ”, a signal 900 that determines “black” is output. 420 is a 1-bit flip-flop that latches the signal output from the look-up table.
It's a flop.

The operation of the second embodiment having the above configuration will be explained in detail below.

Binarized bit map data is sequentially transferred from a host computer (not shown) or a controller in the printer to the monitoring unit 20 shown in FIGS. 16 and 17.
0 registers 201 to 205 sequentially. Also,
The word length of the line memory section 100 shown in FIG. 15 has the data length of one line in the bit map data to be transferred. Here, the output 610 from the register 205 shown in FIG. 17 is input to and stored in the first bit of the line memory section 100. Then, the output 710 from the memory 100 for monitoring the second line data is as shown in FIG.
The data is inputted to register 211 of No. 6, sequentially transferred, and stored in each register 212 to 215. Similarly, the output 620 of the register 215 is input to the second bit of the line memory section 100 and stored as the third line data. Similarly, data from the third line to the fifth line is stored.

As a result, data for a total of 25 pixels, 5 lines x 5 pixels, is stored in the monitoring section 200, as shown in FIG. However, if the pixel at the location marked with an * mark is the pixel of interest D33, the pixel after the pixel of interest is divided into two in both the main scanning and sub-scanning directions, and one pixel is data for four pixels. The monitoring unit 200 forms a monitoring area in which the line two lines before the pixel of interest is the first line, and the fifth line is the fifth line in descending order. Here, the output 723 of the flip-flop 223 shown in FIG. 16 becomes the signal of the pixel of interest D33. Then, the look-up table 300 divides the pixel signal of interest into four parts, 800a and 800a.
b, 800c, 800d, flip-flop 2
24 and is latched. Therefore, after the flip-flop 224, there are 4 bits, and the output signal 630a is
~630d is input as the fourth line data of the line memory section 100 from the third bit to the sixth bit. Similarly, the output signals 730a to 730a from the memory section 100 are
30d is inputted to the register 231 and sequentially shifted, and the output signals 640a to 640d are inputted from the 7th bit to the 10th bit as data on the 5th line of the memory section 100. Then, the output signals 740a to 740d are input to the register 241, and the data is sequentially shifted.

In the first look-up table shown in FIG. 18, the signals 501, 503, 61 of each pixel in the first line, ie, D11, D13, and D15 are
0 is input. Then, the last input line is for each pixel of the fifth line, that is, the signals 741a to 741d, 743a to 743d, 650 of D51, D53, D55.
A to 650d are input. These inputs are input as addresses, and the look-up table 300 outputs a predetermined signal 800 that forms an optimal dot arrangement according to the dot distribution around the pixel of interest D33.

Next, in the second look up table shown in FIG. 19, as shown in FIG. 14, the pixel of interest is D44d, that is, the fourth pixel on the fourth line shown in FIG. These are divided pixels. And the input signals are D33d, D34c, D34d, D35c, D3
5d, D43b・D44a・D44b・D45a・D
45b, D43d・D44c・D44d・D45c・
D45d, D53b/D54a/D54b/D55a
・D55b, D53d・D54c・D54d・D55
c and D55d, these are input as address signals, and the "white" and "black" of the pixel of interest are set in the look-up table 410 to form an optimal dot arrangement according to the dot distribution around the pixel of interest D44d. ” to be determined. The output signal is input to a flip-flop 420 and processed at 4CLK, which is four times the processing speed of one pixel, in accordance with the printing speed of a printer (not shown), and the lighting of the laser is controlled.

As described above, according to the second embodiment, by configuring the monitoring area in multiple stages, detailed processing can be performed and smoother display can be achieved. Also,
The register group can be shared, and the bit map memory has the capacity at the lowest resolution, so there is no increase in cost.

[0035] In the second embodiment, "white" and "black"
However, this is because the resolution could only be improved by up to 2 times in both the main scanning and sub-scanning directions, and even if the resolution was higher, such as 4 times, 6 times, or more. , by dividing the look-up table output from 1 bit to 4 bits to 9 bits,
I can handle it.

The present invention may be applied to a system made up of a plurality of devices, or to an apparatus made up of one device. It goes without saying that the present invention can also be applied to cases where the present invention is achieved by supplying a program to a system or device.

[0037]

[Effects of the Invention] As explained above, according to the present invention,
By monitoring farther areas with minimal memory capacity, it is possible to record higher quality images.

[Brief explanation of the drawing]

FIG. 1 is a block diagram showing the configuration of a data interpolation processing section in a first embodiment.

FIG. 2 is a diagram showing a data structure of a monitoring unit in the first embodiment.

FIG. 3 is a diagram showing a line memory section in the first embodiment.

[Figure 4]

[Figure 5]

FIG. 6 is a diagram showing the configuration of a monitoring unit in the first embodiment.

FIG. 7 is a diagram showing a look-up table in the first embodiment.

FIG. 8 is a diagram showing the configuration of a memory section in the first embodiment.

FIG. 9 is a diagram showing an image before processing.

FIG. 10 is a diagram showing an image after processing.

FIG. 11 is a diagram in which one pixel is divided into both main scanning and sub-scanning directions.

FIG. 12 is a block diagram showing the configuration of a data interpolation processing section in a second embodiment.

FIG. 13 is a diagram showing the data structure of the first monitoring unit in the second embodiment.

FIG. 14 is a diagram showing a data structure of a second monitoring unit in a second embodiment.

FIG. 15 is a diagram showing a line memory section in a second embodiment.

[Figure 16]

FIG. 17 is a diagram showing the configuration of a monitoring unit in a second embodiment.

FIG. 18 is a diagram showing a first look-up table in the second embodiment.

FIG. 19 is a diagram showing a second look up table in the second embodiment.

[Explanation of symbols]

100 Line memory section 200 Monitoring Department 300 Look up table 400 Memory section

Claims (2)

[Claims] 1. An image recording device that stores pixel data in both the main scanning and sub-scanning directions, performs data interpolation for a pixel of interest based on the stored pixel data, and records an image, the device mainly storing pixel data. A storage means for storing data in both the scanning and sub-scanning directions, a reference means for referencing predetermined pixel data stored in the storage means, and a pixel of interest in the main-scanning and sub-scanning directions based on the pixel data from the reference means. An image recording apparatus comprising: a dividing means for dividing the data into both sides; and a recording means for recording according to the data divided by the dividing means. 2. An image recording device that stores pixel data in both the main scanning and sub-scanning directions, performs data interpolation for a pixel of interest based on the stored pixel data, and records an image, wherein the pixel data is a storage means for storing data in both scanning and sub-scanning directions; a first reference means for referring to predetermined pixel data stored in the storage means; and a pixel of interest based on the pixel data from the first reference means. A dividing means that divides the data in both the main scanning and sub-scanning directions, a second reference means that refers to the data divided by the dividing means, and a central pixel is determined based on the data from the second reference means. 1. An image recording device comprising: a determining means.