JP2002158877A - Image data processing method and image data processor - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an image data processor by which a specific image processing mode can be selected in response to the type of application representing the resolution of the object image data at the time of its output and an output model. SOLUTION: The image data processor has a dot correcting means 7 which recognizes the line segment form of the black dots area at its boundary with respect to the white dots area of bit-mapped image data, substitutes code information for the feature of the line segment form recognized for each dot, judges whether the dot necessitates a correction by using at least a part of the code information and performs a correction in response to the code information. The dot correction means 7 has a selection mode setting means 78 which can arbitrarily select whether the number of times of repetitive generation of the identical image data bit-mapped by an image data generating means 72 is set to one arbitrary fixed value or it is alternately set to two or more arbitrary fixed values.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an electrophotographic image forming apparatus using digital image data in an optical printer such as a laser printer, a digital copying machine, a plain paper fax machine, or the like, or image data applied to an image display device. The present invention relates to a processing method and an image data processing device.

[0002]

2. Description of the Related Art Japanese Unexamined Patent Publication No. 5-207282 discloses an image data processing method and apparatus for correcting jaggies of outlines of image data developed in a bitmap form to improve image quality. The data required to be stored in the memory in advance is reduced as much as possible, and the determination of the dots in the image data that need to be corrected and the determination of the correction data for the dots that need to be corrected can be easily performed by a microprocessor or the like. The determination and calculation can be performed in a very short time by the image data processing method described below.

That is, the image data processing method recognizes a line segment shape at a boundary portion between a black dot region and a white dot region of image data developed in a bitmap shape, and recognizes a line segment recognized for each dot. The feature of the minute shape is replaced with a plurality of bits of code information, and at least a part of the code information is used to determine whether or not the dot needs to be corrected. The correction is performed according to.

On the other hand, an image data processing apparatus for realizing the image data processing method includes a window for extracting data of each dot in a predetermined area centered on a dot to be subjected to image data developed in a bitmap form. The line shape at the boundary between the black dot region and the white dot region of the image data is recognized based on the image data extracted through the window, and the characteristics of the line shape recognized for the target dot are recognized. A pattern recognizing means for generating a plurality of bits of code information representing the dot, a discriminating means for discriminating whether or not the dot needs to be corrected by using at least a part of the code information, The correction data stored in advance is read from the dot thus set, using the code information generated by the pattern recognition means as an address. It was equipped with a correction data memory for out output.

According to the image data processing method and the apparatus described above, the line segment of the boundary portion (contour line of a character or the like) between the black dot region and the white dot region of the image data developed in the bitmap shape. Recognize the shape, replace each dot with multiple bits of code information, use at least a part of the code information to determine whether the dot needs to be corrected, Performs correction in accordance with the code information, so that it is not necessary to create and store in advance all feature patterns that need to be corrected as a template. It was possible to easily determine the correction data using the code information in a short time. Further, as disclosed in Japanese Patent Application Laid-Open No. 07-087321, "Image Data Processing Apparatus", arbitrary information in the main scanning and sub-scanning directions concerning image data is added to the code information. ,
At the same time as performing jaggy correction, enlargement of image data,
It was also possible to realize density conversion to higher resolution.

However, in the above-mentioned prior art, there is no function related to reduction of image data. As a similar image data reduction function in other conventional techniques, it is possible to reduce image data by controlling whether or not to read out image data stored in a page memory in advance. There were some, but because the original image data was simply deleted or multiple readings were performed discontinuously, the former case may cause image degradation, and the latter case Although there is little possibility of causing image deterioration, the effect of jaggy correction cannot be obtained at the same time.

[0007]

As described above, even in the prior art, when the jaggies of the contour lines are corrected for the image data developed in the bitmap form to improve the image quality, the correction is performed in advance. There is no need to create and store all necessary feature patterns as templates, making it easy to determine which dots need to be corrected and determine correction data for dots that need to be corrected using multi-bit code information. Although it can be performed in a short time, it has no function of reducing image data. Also,
In some cases, it was possible to reduce the size of the image data by controlling whether or not to read out the image data stored in the page memory in advance. Although it is unlikely to cause deterioration,
The effects of jaggy correction could not be obtained at the same time.

SUMMARY OF THE INVENTION The present invention has been made in view of the above-described problems, and it is intended to improve image quality by correcting jaggies of contour lines in image data developed in the form of a bitmap, and to improve the image quality of the original bitmap. By repeatedly generating the same image data developed in the form of a bitmap at the same timing with respect to a signal generated at an arbitrary periodicity, the image data developed in the form of a By expanding the size of the data relating to the expanded image data to an arbitrary multiple and adding information generated from information from an arbitrary periodically generated signal, a more detailed jaggy correction of the contour line can be performed. At the same time as improving the image quality, it is also possible to output a highly accurate reduced or enlarged image from the original image, or Scales further higher resolution, and,
An object of the present invention is to facilitate setting of a reduction ratio or an enlargement ratio, and to solve the problems of the following claims.

(1) Problems with Claims 1 and 4 At the same time as enabling jaggy correction, image data can be reduced or enlarged in the sub-scanning direction without erasing the original image. The degree of freedom in selecting an image processing mode, such as enabling a change, is improved. (2) Problems to be Solved by Claims 2 and 5 By determining a unique image processing mode in accordance with the resolution at the time of outputting target image data, the overall control of the image data processing system is facilitated. (3) Problems for Claims 3 and 6 In addition to the objects of Claims 2 and 5, the overall control of the image data processing system is facilitated by increasing the degree of freedom in selecting an image processing mode applied to the target image data. This achieves high quality of the output image.

[0010]

According to the first aspect of the present invention, a line segment shape at a boundary portion between a black dot region and a white dot region of image data developed in a bit map is recognized, and each dot is recognized. The feature of the line segment shape recognized and replaced is replaced with a plurality of bits of code information, and at least a part of the code information is used to determine whether or not the dot needs to be corrected. Is an image data processing method for correcting image data by outputting correction data corresponding to the code information. In the image data processing method in which the correction is performed on each of the same image data expanded in a bitmap shape, the same image data expanded in a bitmap shape is repeatedly It is possible to arbitrarily select and set any one of a case where the number of repetition generations to be performed is set to an arbitrary fixed value and a case where two or more arbitrary fixed values are alternately and repeatedly set. An image data processing method characterized by having a selection mode setting method.

According to a second aspect of the present invention, in the first aspect of the present invention, the selection mode setting method can individually select and set according to the output resolution of image data developed in a bitmap form. Is an image data processing method characterized by the following.

According to a third aspect of the present invention, in the first or the second aspect of the present invention, the selection mode setting method is performed individually according to a type of an application indicating a model for outputting image data expanded in a bitmap form. This is an image data processing method characterized in that it can be selected and set.

According to a fourth aspect of the present invention, a line segment shape of a boundary portion between a black dot region and a white dot region of image data developed in a bit map is recognized, and the line segment recognized for each dot is recognized. The feature of the shape is replaced with a plurality of bits of code information, and at least a part of the code information is used to determine whether or not the dot needs to be corrected. An image data processing apparatus having a dot correction means for outputting correction data corresponding to the image data to correct the image data, wherein the dot correction means has the same timing with respect to an arbitrary periodically generated signal. And an image data generating means for repeatedly generating the same image data developed in the form of a bit map, and developing the image data in the form of a bit map repeatedly generated by the image data generating means. In the image data processing device in which the correction is performed for each of the same image data obtained, the number of times that the same image data expanded into a bitmap is repeatedly generated by the image data generating means is repeatedly generated. And a selection mode setting means that can arbitrarily select and set any one of a case where any one fixed value is set and a case where two or more fixed values are alternately and repeatedly set. An image processing apparatus characterized in that:

According to a fifth aspect of the present invention, in the fourth aspect of the present invention, the selection mode setting means can individually select and set according to the output resolution of the image data developed in a bitmap form. An image data processing apparatus characterized by the following.

According to a sixth aspect of the present invention, in the fourth or fifth aspect of the present invention, the selection mode setting means individually selects the type of application indicating a model for outputting image data developed in a bitmap form. An image data processing apparatus characterized in that it can be selected and set.

[0016]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiments of the present invention will be specifically described below with reference to the drawings. FIG. 2 is a block diagram showing an example of the configuration of a laser printer which is an image forming apparatus as an embodiment showing the configuration of the image data processing apparatus according to the present invention. The laser printer 1 includes a controller 3, an engine driver 4, a printer engine 2, and an internal interface 6. And the laser printer 1
The print data transferred from the host computer 5 is received, developed by the controller 3 into bitmap data in page units, converted into video data (image data) as dot information for driving a laser, and converted into an internal interface 6. To the engine driver 4 via
The printer engine 2 is sequence-controlled to form a visible image on a sheet.

The internal interface 6 includes a dot correction section 7 which is a component of the image data processing apparatus according to the present invention. In the dot correction section 7, video data (image data) transmitted from the controller 3 is provided. 2) performs dot correction based on the image data processing method according to the present invention to improve image quality. The controller 3 includes a main microcomputer MPU (hereinafter, referred to as “MPU”) 31, a program required by the MPU 31,
ROM 32 storing constant data and character fonts
And RA for recording general data, dot patterns, etc.
M33, an I / O 34 for controlling input / output of data, and an operation panel 35 connected to the MPU 31 via the I / O 34, and are connected to each other by a data bus, an address bus, a control bus, and the like. . Further, the host computer 5 and the internal interface 6 including the dot correction unit 7 are also connected to the MPU 31 via the I / O 34.

The engine driver 4 includes a sub-microcomputer CPU (hereinafter referred to as "CPU") 41, a ROM 42 storing programs and constant data required by the CPU 41, and a RAM for recording temporary data.
43, and an I / O 44 for controlling data input / output, and are connected to each other via a data bus, an address bus, a control bus, and the like.

The I / O 44 is connected to the internal interface 6 to input video data (image data) from the controller 3 and the state of various switches on the operation panel 35, and to output status signals such as an image clock WCLK and a paper end. Is output to the controller 3. In addition, the I /
O44 is also connected to a writing unit 26 and other sequence device group 27 constituting the printer engine 2, and various sensors 28 including a synchronous sensor described later.

The controller 3 includes a host computer 5
Command, such as a print command, and print data such as character data and image data, and edits them, and converts them into a dot pattern necessary for image writing using a character font stored in the ROM 32 if the character code is used. Bitmap data (dot patterns) of characters and images (hereinafter collectively referred to as "images")
The image data is expanded in the video RAM area 33 in page units.

When the image clock WCLK is input together with the ready signal from the engine driver 4, the controller 3 synchronizes the bit map data (dot pattern) developed in the video RAM area in the RAM 33 with the image clock WCLK. The data is output to the engine driver 4 via the internal interface 6 as video data (image data). An image data processing apparatus according to the present invention is realized by performing dot correction on the video data (image data) in the dot correction unit 7 in the internal interface 6 so that an operation mode can be arbitrarily selected as described later. .

Further, on the operation panel 35, switches and indicators (not shown) are provided to control various kinds of data and to transmit the instructed information to the engine driver 4 in accordance with an instruction by an operator operating the switch. To tell
Display the status of the printer on the display.

The engine driver 4 uses the video data (image data) from the controller 3 which has been dot-corrected and input via the internal interface 6 to write a unit 26 of the printer engine 2 and a charger, a developing unit and the like to be described later. Video data (image data) necessary for controlling the sequence equipment group 27 etc.
Is input via the internal interface 6 and output to the writing unit 26. At the same time, a signal indicating the state of each part of the printer engine 2 is input from a synchronous sensor or other sensors 28 for processing, necessary information or error status. A status signal (for example, paper end) is output to the controller 3 via the internal interface 6.

FIG. 3 is a schematic diagram showing an example of the mechanism of the printer engine 2 in the laser printer 1 shown in FIG. According to the laser printer 1, the paper 11 is fed from one of the upper and lower paper cassettes 10a and 10b, for example, the paper stack 11a of the upper paper cassette 10a by the paper feed roller 12a. Is timed by the pair of registration rollers 13 and then conveyed to the transfer position of the photosensitive drum 15.

The surface of the photosensitive drum 15, which is driven to rotate in the direction of the arrow by the main motor 14,
6 and the PWM from the writing unit 26
(Pulse Width Modulation) By scanning with a modulated spot, an electrostatic latent image is formed on the surface.
The electrostatic latent image is visualized by attaching toner to the developing unit 17, and the visualized toner image is transferred onto the sheet 11 conveyed by the pair of registration rollers 13 by the action of the transfer charger 18. Is transferred from the photosensitive drum 15 to the fixing unit 25 by the conveyor belt 19, and is pressed against the fixing roller 20b by the pressing roller 20a. And the temperature of the fixing roller 20b.

The paper 11 exiting the fixing unit 25 is discharged by a discharge roller 21 to a discharge tray 22 provided on a side surface. On the other hand, the toner remaining on the photosensitive drum 15 is removed and collected by the cleaning unit 23. A plurality of printed circuit boards 2 constituting a controller 3, an engine driver 4, and an internal interface 6 are provided above the laser printer 1, respectively.
4 are mounted.

FIG. 4 is a perspective view of an essential part showing a configuration example of the writing unit 26 in the laser printer 1 shown in FIG. The writing unit 26 is an LD (laser diode)
A rotary deflector 56 including a unit 50, a first cylinder lens 51, a first mirror 52, an imaging lens 53, a disk-type motor 54, and a polygon mirror 55 rotated in the direction of arrow A by the disk-type motor 54; , A second mirror 57, a second cylinder lens 58 and a third mirror 60, a condenser lens 61 composed of a cylinder lens, and a synchronization sensor 62 composed of a light receiving element.

The LD (laser diode) unit 5
0 indicates a laser diode (hereinafter referred to as “LD”) inside
And a collimator lens for converting a divergent beam emitted from the LD into a parallel light beam. The first cylinder lens 51 has a function of shaping the parallel light beam emitted from the LD unit 50 on the photosensitive drum 15 in the sub-scanning direction, and forms an imaging lens 53.
Converts the parallel light reflected by the first mirror 52 into a convergent beam and makes it incident on the mirror surface 55 a of the polygon mirror 55.

The polygon mirror 55 has a mirror surface 55a.
Is formed as a curved R polygon mirror, so that a post object that does not use an fθ lens (that is, a lens whose imaging size is proportional to the incident angle θ) conventionally disposed between the second mirror 57 and the second mirror 57 is used. Rotating polarizer 5 of the type (a type in which a deflector is arranged after converging a light beam into a light beam)
6 are formed. The second mirror 57 includes a rotating polarizer 56.
The beam (scanning beam) reflected and deflected by the light is reflected toward the photosensitive drum 15. The second mirror 57
The scanning beam reflected by the above-mentioned forms an image as a sharp spot on the main scanning line 15 a on the photosensitive drum 15 via the second cylinder lens 58.

The third mirror 60 has a rotating polarizer 56.
Is arranged outside the scanning area on the photosensitive drum 15 by the light beam reflected by the
Reflects toward the two sides. The light beam reflected by the third mirror 60 and condensed by the condenser lens 61 is converted into a synchronization signal for keeping the scanning start position constant by a light receiving element such as a photodiode constituting the synchronization sensor 62. You.

FIG. 5 is a block diagram showing an example of a schematic configuration of the dot correction section 7 shown in FIG. 2. FIG. 7 is a specific configuration example of a main part (the FIFO memory 72 and the window 73) of the dot correction section 7. FIG. As shown in FIG. 5, the basic configuration of the dot correction unit 7 is a parallel / serial converter (hereinafter referred to as “P / S converter”) 7.
1, image data generation means (FIFO memory) 72, window (shift register) 73, pattern recognition unit 74,
A memory block 75, a video data output unit 76, and
It is constituted by a timing control section 77 for controlling the above-mentioned respective circuit blocks synchronously.

When the video data (image data) transferred from the controller 3 shown in FIG. 2 is parallel (8 bits) data, the P / S converter 71 converts the video data (image data) into serial (1 bit) data. It is provided to convert the data into data and send it to the FIFO memory 72 which is the image data generating means, and basically does not participate in dot correction. When the video data (image data) transferred from the controller 3 is serial data,
The P / S converter 71 is unnecessary.

The FIFO memory 72 serving as image data generating means includes a first-in first-out memory.
As shown in FIG. 7, the line buffers 72a to 72g respectively storing video data (image data) for a plurality of lines (seven lines in this embodiment) sent from the controller 3 include multiplexers. 7
21 is serially connected.

Here, when the data-sel signal from the timing signal generating means provided in the timing control unit 77 described later is "0", the multiplexer 721 sends the data from the controller 3 via the P / S converter 71. Serial video data (image data) and output data (A input) from the line buffers 72a to 72f.
Is "1", the output data (B input) from the line buffers 72a to 72g is selected and input, and is stored in the line buffers 72a to 72g.

Accordingly, the operation of the FIFO memory 72 is as shown in the timing chart of FIG. 8 or FIG. That is, the video data (the numerical values 1, 2, 3, 4, etc. given in FIG. 8 or FIG.
The output of each line buffer 72a to 72g becomes an output as shown in FIG. 8 or FIG. 9 by the data-sel signal which is an arbitrary timing signal with respect to the input of As code information indicating the number of times the output of each of the line buffers 72a to 72g is repeatedly generated,
The count signal (A [13:12]) in the figure is output. That is, the number of times of generation of repetition
9 shows two times, and FIG. 9 shows three times.

However, at this time, the first data is stored in the FIFO memory 72 as shown in FIG.
During the period in which the −sel signal is “0”, only the data write signal is asserted and each line buffer 72 is asserted.
Only data writing is performed on a to 72g, and thereafter, the data write signal and the read signal are controlled so that assertion and negation are alternately repeated so that the written data is reliably read. Further, the operation of the FIFO memory 72 is an embodiment of the image data generating means constituting the image data processing device in the present invention.

In the window 73, 11-bit shift registers 73a to 73g are serially connected to seven lines of data output from the line buffers 72a to 72g of the FIFO memory 72, respectively.
A window for pattern detection, that is, a sample window (FIG. 11 shows an example of the shape of the window) is configured. Here, the middle bit (indicated by an X mark in FIG. 7) of the shift register 73d located at the center of the window 73 shown in FIG. 7 is the storage position of the target dot of interest. Incidentally, as shown by the broken-line frames in FIG. 11, each of the shift registers 73a to 73
Of the 3g, the shift registers 73a and 73g only need 7 bits, and the shift registers 73b and 73f only need 8 bits, and the portion shown by the broken line in FIG.

As the video data (image data) is sequentially shifted one bit at a time in the line buffers 72a to 72g constituting the FIFO memory 72 and the shift registers 73a to 73g constituting the window 73, the dot of interest sequentially changes. Then, video data (image data) of the window 73 centered on each changed dot of interest can be continuously extracted.

The pattern recognition section 74 shown in FIGS.
Is based on the dot information extracted from the window 73,
A target dot, that is, a target dot and information around the target dot, in particular, features of a line segment shape at a boundary between a black dot and a white dot of video data (image data) are recognized, and the recognition result is determined in advance. And output as multi-bit code information in the specified format. The code information becomes an address code of the memory block 75 shown in FIG.

FIG. 12 shows a pattern recognition section 74 shown in FIG.
FIG. 4 is a block diagram showing an internal configuration of the device and a relationship with a window 73, and further, each output signal of a pattern recognition unit 74. A window 73 which is a sample window shown in FIG.
As shown in FIG. 12, a central 3 × 3 bit core area (Core) 73C and an upper area (U
(Upper) 73U and lower region (Lower) 73D;
Further, a left area (Left) 73L and a right area (Rig)
ht) 73R. The window 73
For details, refer to Japanese Patent Application Nos. 3-314828 and 4-301395, or 5-187.
Since the content is exactly the same as that described in No. 058, the description is omitted here.

The pattern recognition section 74 shown in FIG. 12 includes a core area recognition section 741, a peripheral area recognition section 742, multiplexers 743 and 744, a gradient calculation section 745, a position calculation section 746, a determination section 747, The peripheral region recognition unit 742 further includes an upper region recognition unit 742U,
It is composed of a right area recognition section 742R, a lower area recognition section 742D, and a left area recognition section 742L. The operation of each circuit block of the pattern recognition unit 74 is exactly the same as the content described in Japanese Patent Application Nos. 3-14928 and 4-301395, and thus the description thereof is omitted here.

Next, a specific configuration example and operation of the memory block 75 shown in FIG. 5, that is, the correction data output means, will be described with reference to FIGS. The configuration example of the memory block 75 shown in FIG.
The contents are exactly the same as those described in Japanese Patent Application No. 314928 and Japanese Patent Application No. 4-301395, and the memory block 75 comprises only a pattern memory 751. Using the code information (12 bits) output from the pattern recognition unit 74 as an address, correction data (10 bits) stored in advance
And outputs video data (image data) for laser driving. The output video data (image data) becomes a corrected dot pattern.

The configuration example of the memory block 75 shown in FIG. 14 shows another configuration example. In this configuration example, the memory block 75 is composed of only the pattern memory 751. However, not only the code information (12 bits) output from the pattern recognition unit 74, but also the video data (image data) output from the FIFO memory 72, which is the above-described image data generation means, to an arbitrary timing signal The count signal A [13:12], which is information indicating the number of times that the number of times of repetition has been generated.
Using the code information of a total of 14 bits including (2 bits) as an address, the correction data stored in advance is read, and video data (image data) for laser driving is output. The output video data (image data) becomes a corrected dot pattern.

Therefore, unlike the configuration example of the memory block shown in FIG. 13, the image data (video data) to be corrected is generated by repeating the arbitrary number of times for an arbitrary timing signal. The count signal A [13:12], which is information indicating whether the image data is
Since the correction data is read from the pattern memory 751 using the address to which (2 bits) are added, even for the code information indicating the same line segment shape, different corrections unique to each generation count are performed. It is possible to output a dot pattern of data. This configuration example of the memory block is an embodiment in which the image data processing apparatus according to the present invention provides a correction data output unit that outputs appropriate correction data for each dot of an original image.

The correction data output from the memory block 75 of the configuration example as described above includes a plurality of regular widths, that is, laser emission times, for each dot of video data (image data) sent from the controller 3. Are output in parallel as information of an integral multiple of the value divided into (the maximum value in the case of division into ten is ten times).

The video data output unit 76 shown in FIG. 5 is a light source provided in the writing unit 26 of the printer engine 2 after serializing the parallel information output from the memory block 75 and sending it to the printer engine 2. LD
A signal source for turning on / off the laser diode of the unit 50. However, the above-described ON / OFF control of the laser diode of the LD unit 50 is based on the control based on binary data. However, when the control based on multi-valued data is assumed, the memory block 75 in the video data output unit 76 is used. As described above, there is no need to serialize the parallel information output from the printer engine and send the serialized information to the printer engine 2. That is, the parallel information from the memory block 75 is converted into parallel multi-valued image data for performing ON / OFF control and power control of the laser diode of the LD unit 50 (in such a case, it becomes a multi-value control LD unit). The parallel information is written to the writing unit 26 as it is by making it correspond to (video data).

The present invention relates to the above-described image data processing apparatus, and the configuration and operation of the image data processing apparatus according to the present invention will be described in detail below. FIG. 1 is a block diagram showing an example of a schematic configuration of the dot correction unit 7 in the image data processing device according to the present invention. In the configuration example of FIG.
Is added to the configuration of the dot correction section 7 shown in FIG. 7 to select the number of times the same image data is repeatedly generated in the FIFO memory 72, which is the image data generating means, and set it to an arbitrary number. And prepare for it.

The selection mode setting means 78 includes a generation number setting means 781.
81 is an arbitrary number of generations for outputting the same image data to the window 73 from the FIFO memory 72 in which the image data expanded in a bitmap form is stored a plurality of times with respect to an arbitrary timing signal. This is a means for setting the number of times. The selection mode setting means 78 causes the generation number setting means 781 to set not only the number of repetition generation times but also any one fixed value specified for the number of repetition generation times as a repetition mode, or It is possible to select whether the above-mentioned specified fixed values are set alternately and repeatedly.

The operation of the generation mode setting unit 781 of the selection mode setting unit 78 will be described with reference to the image diagrams of the image data (video data) illustrated in FIGS.
Further explanation will be given. First, FIG. 1 shows an embodiment of jaggedness correction with resolution double processing for an original image.
5 will be described. FIG. 15 is an image diagram of image data (video data) when the number-of-generations setting unit 781 shown in FIG. 1 sets three times as the number of times of repeated generation of the same image data. The figure shows how the image of the image data (video data) as the output result when the setting is made to perform the replacement with the image correction data. Here, the original image data (video data) is generated three times as a printer output by repeating the original image data (video data) with respect to the line synchronization signal LSYNC indicating the write start timing of each line of the main scan, and the output image data of the FIFO memory 72 As shown in FIG. 15, (video data) is output to the pattern recognition unit 74 shown in FIG. 1 in the sub-scanning direction at a cycle of 1/3 of the time of printing at the resolution of the original image data (video data). I do.

The code information (12 bits) indicating the characteristics of the recognized line segment output from the pattern recognition unit 74 is the same code information for the dot positions respectively corresponding to the three repetitions. However, as the address to the memory block 75, the count signal A [13: 1] shown in FIG. 9 indicating the number of generations of the image data (bit data) developed in the same bitmap shape is used.
2] (2 bits) is added to the code information (12 bits), so that a different address is indicated for each generation count. Therefore, the memory block 7
5 can be different image data (video data), and like the image of the image data (video data) shown in FIG. 15, image data (video data) corresponding to the number of generations. Can be output.

Next, FIG. 16 shows an embodiment in which the jaggy correction accompanied by the process of doubling the resolution of the original image and the reduction of the image in the sub-scanning direction without complete erasure of the original image are realized at the same time. It will be described using FIG.
FIG. 16 is an image diagram of image data (video data) when the generation number setting unit 781 shown in FIG. 1 alternately sets two values of three and two as the number of times of repeated generation of the same image data. This shows how the image data (video data) as an output result when replacing with different image correction data for each generation count is set.

Here, as a printer output, a line synchronizing signal L indicating the write start timing of each line of main scanning
For the SYNC, the original image data (video data) is alternately generated three times and twice, and the control as shown in the operation timing chart of the FIFO memory 72 shown in FIG. 10 is performed. Naru, FI
The output image data (video data) of the FO memory 72 is
As shown in FIG. 16, the data is output to the pattern recognition unit 74 shown in FIG. 1 at a cycle of 1/3 with respect to the printing at the resolution of the original image data (video data) in the sub-scanning direction.

Similarly to the case shown in FIG. 15, the code information (12 bits) output from the pattern recognition unit 74 and indicating the characteristics of the recognized line segment shape is obtained by repeating the dot positions respectively corresponding to three or two times. Are the same code information. However, as the address to the memory block 75, FIG. 10 showing the number of generations of the image data (bit data) developed in the same bitmap shape as described above
Since the count signal A [13:12] (2 bits) is added to the code information (12 bits),
A different address is indicated for each generation count. Therefore, the output data of the memory block 75 can also be different image data (video data), and like the image of the image data (video data) shown in FIG. (Video data) can be output.

Here, in FIG. 16, the jaggies correction accompanied by the resolution double processing of the original image shown in FIG. 15 is performed, and at the same time, in the sub-scanning direction of the image without complete erasure of the original image. Is also realized, and the reduction ratio of the image can be made variable by a combination of the set values set in the generation number setting means 781. That is, in FIG. 16, the same image data set by the generation number setting means 781 is repeatedly and alternately generated three times and two times. As shown, the image data of the sub-scanning lines indicated by 1-3, 3-3, and 5-3 is not generated (in FIG. 16, the 3-3 sub-scanning line is indicated by a white broken elliptical mark). In comparison with the image of the output image data shown in FIG. 15, the image data is output in a state where the sub-scanning lines corresponding to the lines 1-3, 3-3, and 5-3 are deleted. Therefore, the image data is reduced in the sub-scanning direction.

In the embodiment described above, the combination of the set values set in the number-of-generations setting means 781 is:
Although the combination of the two set values of three and two times is performed alternately and repeatedly, in order to increase the resolution of the image reduction ratio or the enlargement ratio, the combination of three or more set values is alternately performed. Repetition can be achieved by changing the setting operation of the selection mode setting means 78 to the generation count setting means 781.

As described above, in FIG. 10, three times and two times are alternately selected as the number of times the original image data is repeatedly generated by the number-of-generations setting means 781, and the original image data is set to 5/6. That is, about 8
This is the operation when the reduction can be made to 3.3%.

Here, taking the reduction of image data as an example, if the reduction ratio R is expressed as a calculation formula, the following expression (1) is established. That is, assuming that the set number of repetitive generations is n and m, the number of basic generations is three, R = (n + m) / (3 + 3) (1)

The set values of n and m can be any one of "1", "2", and "3" within three basic generation times. Here, “0” is a complete image loss, and cannot be selected in principle. Therefore,
From equation (1), the possible reduction rate R is 2/6 (33.3
%), 3/6 (50%), 4/6 (66.7%), 5 /
6 (83.3%). In addition, generation number setting means 78
By adding one more set value of the number of times of repetition to be set to 1, and setting the number to n, m, and l, the possible reduction rate R is 3/9 (33.3%), 4/9 (44.
4 /), 5/9 (55.6%), 6/9 (66.7%),
The resolution of the reduction ratio R is improved, such as 7/9 (77.8%) and 8/9 (88.9%).

FIG. 6 is a block diagram showing another example of the schematic configuration of the dot correction section in the image data processing apparatus according to the present invention. The selection in the dot correction section 7 of the image data processing apparatus described with reference to FIG. As the mode setting means 78, in addition to the number-of-generations setting means 781, information on the output resolution of image data (video data) developed in a bitmap form is set, and furthermore, the type of output model for outputting the image data A mode setting unit 782 for setting type information of an application indicating (copy, facsimile, printer, etc.) is further provided.

For example, the image data (video data) handled by the image data processing apparatus is sent to the mode setting means 782 in the selection mode setting means 78 shown in FIG. ), The number of repetitions and the repetition mode (repetition by one specified fixed value or two or more specified fixed values are set in the number-of-generations setting means 781). An operation mode indicating whether the change is repeated alternately) is selected and designated. That is, FIG.
The image processing mode can be selected in accordance with the processing procedure of the flowchart shown in FIG. 18 and the processing result of the image data (video data) output by the image data processing apparatus is output for each output resolution. It is possible to select and output as a processing result of either 15 or FIG.

FIG. 17 is a flowchart for explaining an example of the operation of the mode setting means 782 of the image data processing apparatus according to the present invention. According to the specified value, it is possible to request to set a different number of repetition generations. FIG. 18 is a flowchart for explaining an example of the operation of the generation count setting unit 781 of the image data processing apparatus according to the present invention. Either the number of times is fixedly set to m or the number of times is set alternately between m and n.

Further, as described above, the image data (video data) expanded in a bitmap format is output to the mode setting means 782 in FIG. 6 by any application (for example, an output model such as a facsimile, a printer, and a copy).
It is also possible to make the setting possible including the information as to whether the image is an output image. In such a case, the mode setting of the output resolution of the image data (video data) handled by the image data processing apparatus and the information indicating the type of the application as the output model is performed for each of the image data developed in the bitmap form. By making settings for the means 782, the number of repetitions and the repetition mode to be set by the generation number setting means 781 are selected and designated. That is, the image processing mode can be selected in accordance with the processing procedure of the flowcharts shown in FIGS. 19 and 20, and the processing result of the image data (video data) output by the image data processing apparatus is output for each output resolution. Furthermore, it is possible to selectively output as a processing result of either FIG. 15 or FIG. 16 for each type of application indicating an output model such as copy, facsimile, and printer.

FIG. 19 is a flowchart for explaining the operation of the output resolution judging unit as another example of the operation of the mode setting means 782 of the image data processing apparatus according to the present invention. Different parameters can be set according to the change designation of the output resolution and the designated value of the output resolution to instruct the selection operation of the application. On the other hand, FIG. 20 is a flowchart for explaining the operation of the application determination unit as another example of the operation of the mode setting unit 782 of the image data processing apparatus according to the present invention. Set different parameters from the output resolution determination unit shown
It is started by designating an application selection operation, and can request the generation count setting unit 781 to set different numbers of repetition generations according to information indicating the type of application set as the output model. . In response to the request for setting the number of times of repeated generation, as shown in FIG.

The timing control unit 77 and the memory block 75 of the dot correction unit 7 shown in FIG. The timing control unit 77 receives a frame gate signal FGATE for defining a writing period for one page from the engine driver 4, a line gate signal LGATE for defining a writing period for one line, and line synchronization indicating the start and end timings of writing of each line. A signal LSYNC signal, an image clock WCLK for synchronizing reading and writing for each dot, and a reset signal R
Using ESET as an input signal, each of the circuit blocks 7 described above is used.
For 1 to 76, a clock signal and the like necessary for synchronizing the respective operations are generated.

The correction data stored in the memory block 75 in advance is stored in the MPU of the controller 3 shown in FIG.
31 or the CPU 41 of the engine driver 4
It is also possible to selectively load the data from the ROM 32 or the ROM 42 or to download the data from the host computer 5. By enabling the loading operation, the correction data of the image data (video data) for the correction target pattern can be easily changed. It is possible to do.

As described above, window area division for matching in the window 73 and its detection pattern and use area, or the pattern recognition unit 7
4 about the operation of each circuit block 741 to 748, each output signal from each of the circuit blocks 741 to 748, and a specific dot correction method.
The contents are exactly the same as those described in Japanese Patent Application No. Hei 3-31428 or Japanese Patent Application No. Hei 4-301395, and the description is omitted here.

Finally, in the above-described embodiment, the dot correction section 7 which is an image data processing device according to the present invention is provided inside the internal interface 6 connecting the controller 3 of the laser printer 1 and the engine driver 4. Although the case has been described, the dot correction unit 7 may be provided on the controller 3 side or the engine driver 4 side.

Further, the present invention is not limited to a laser printer, but various image forming apparatuses for forming an image by developing in a bit map form such as an LED printer and other various optical printers, digital copying machines, and plain paper fax machines. In addition, the present invention can be similarly applied to an image display device that displays an image formed by being developed in such a bitmap shape.

[0069]

(1) Effect of the invention as set forth in claims 1 and 4 Selection mode setting in which the number of times of repetition generation is set to one fixed value, or alternately set to two or more arbitrary fixed values Means that enables jaggy correction with double-density processing of the resolution of the original image and at the same time reduces or expands image data in the sub-scanning direction without erasing the original image, and further reduces or enlarges the image. It is possible to freely select an image processing mode, for example, it is possible to change the image processing mode.

(2) Advantageous Effects of the Invention According to Claims 2 and 5, a unique image processing mode can be determined according to the resolution at the time of outputting the target image data, and the overall control of the image data processing apparatus is achieved. Can be facilitated.

(3) Effects of the Inventions According to Claims 3 and 6 In addition to the effects described in claims 2 and 5, an application which is a target model of image data processing (ie, an output model of an image data processing result) is selected. By doing so, the degree of freedom in selecting an image processing mode to be applied to the target image data can be further increased, and the overall control of the image data processing apparatus can be further facilitated and the output image quality can be improved. be able to.

[Brief description of the drawings]

FIG. 1 is a block diagram illustrating an example of a schematic configuration of a dot correction unit in an image data processing device according to the present invention.

FIG. 2 is a block diagram illustrating an example of a configuration of a laser printer which is an image forming apparatus as one embodiment illustrating the configuration of the image data processing apparatus according to the present invention.

FIG. 3 is a schematic configuration diagram showing an example of a mechanism of a printer engine 2 in the laser printer 1 shown in FIG.

FIG. 4 is a perspective view of a main part showing a configuration example of a writing unit 26 in the laser printer 1 shown in FIG.

FIG. 5 is a block diagram showing an example of a schematic configuration of a dot correction unit 7 shown in FIG.

FIG. 6 is a block diagram illustrating another example of a schematic configuration of the dot correction unit in the image data processing device according to the present invention.

FIG. 7 shows a main part (FIFO) of the dot correction unit 7 shown in FIG.
FIG. 3 is a block diagram showing a specific configuration example of a memory 72 and a window 73).

8 is a timing chart showing an example of the operation of the FIFO memory 72 shown in FIG.

FIG. 9 is a timing chart showing another example of the operation of the FIFO memory 72 shown in FIG. 7;

FIG. 10 is a timing chart showing another example of the operation of the FIFO memory 72 shown in FIG. 7;

11 is a diagram showing an example of the shape of a window 73 shown in FIG.

12 is a block diagram showing an internal configuration of a pattern recognition unit 74 shown in FIG. 5 and a relationship with a window 73, and further, each output signal of the pattern recognition unit 74. FIG.

13 is a block diagram showing an example of a configuration of a memory block 75 shown in FIG.

14 is a block diagram showing another example of the configuration of the memory block 75 shown in FIG.

15 is an image diagram of image data (video data) when the number of generations of the same image data is set to three times in the number-of-generations setting unit 781 shown in FIG.

16 is an image diagram of image data (video data) in a case where two values of three times and two times are alternately set as the number of times of repeated generation of the same image data in the generation number setting unit 781 shown in FIG. .

FIG. 17 is a flowchart illustrating an example of an operation of a mode setting unit 782 of the image data processing device according to the present invention.

FIG. 18 is a flowchart illustrating an example of the operation of the generation count setting unit 781 of the image data processing device according to the present invention.

FIG. 19 is a flowchart illustrating the operation of an output resolution determination unit as another example of the operation of the mode setting unit 782 of the image data processing apparatus according to the present invention.

FIG. 20 is a flowchart illustrating an operation of a determination unit of an application as another example of the operation of the mode setting unit 782 of the image data processing device according to the present invention.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Laser printer, 2 ... Printer engine, 3 ... Controller, 4 ... Engine driver, 5 ... Host computer, 6 ... Internal interface (internal I / F), 7 ... Dot correction part, 10a, 10b ... Paper feed cassette, 11 ... Paper, 11a ... Paper stack, 12a, 12b ... Paper feed roller, 13 ... Register roller pair, 14 ... Main motor, 1
5 photosensitive drum, 15a main scanning line, 16 charging charger, 17 developing unit, 18 transfer charger,
19: Conveying belt, 20a: Pressure roller, 20b: Fixing roller, 21: Discharge roller, 22: Discharge tray, 23:
Cleaning unit, 24 ... printed circuit board, 25
... fixing unit, 26 ... writing unit, 27 ... sequence equipment group, 28 ... sensors, 31 ... main microcomputer MPU, 32 ... ROM, 33 ... RAM, 34 ...
I / O, 35: Operation panel, 41: Sub microcomputer CPU, 42: ROM, 43: RAM, 44: I
/ O, 50 ... Laser diode (LD) unit, 51
.. A first cylinder lens, 52 a first mirror, 53 an imaging lens, 54 a disk type motor, 55 a polygon mirror, 55 a a mirror surface, 56 a rotary deflector, 57 a second
Mirror, 58: second cylinder lens, 60: third mirror, 61: condenser lens, 62: synchronous sensor, 71: parallel serial converter (P / S converter), 72:
Image data generating means (FIFO memory), 72a to 7
2g: line buffer, 73: window (shift register), 73a to 73g: shift register, 73C ...
Core area 73D Lower area 73L Left area 73R
Right area, 73U: Upper area, 74: Pattern recognition unit, 75
... memory block, 76 ... video data output unit, 77 ...
Timing control section, 78... Selection mode setting means, 721
... Mux, 741 ... Core area recognition unit, 742 ...
Peripheral area recognition unit, 743, 744... Multiplexer, 7
45: Gradient calculation unit, 746: Position (Positi)
on) Calculation unit, 747: determination unit, 748: gate, 751
... pattern memory, 781 ... generation number setting means, 782
... Mode setting means.

Claims (6)

[Claims] 1. A method for recognizing a line segment shape at a boundary portion between a black dot region and a white dot region of image data developed in a bitmap shape, and using a plurality of features of the line segment shape recognized for each dot. It replaces with the bit code information, determines whether the dot needs to be corrected by using at least a part of the code information, and corrects the correction data according to the code information for the dot determined to need correction. An image data processing method for correcting image data by outputting the same, and furthermore, the same image developed in the form of a bit map repeatedly generated at the same timing with respect to an arbitrary periodically generated signal. In the image data processing method in which the correction is performed on each of the data, the number of times of repetition generation at which the same image data developed in a bitmap form is repeatedly generated is arbitrary. The method has a selection mode setting method that can arbitrarily select and set any one of a case where the fixed value is set to one fixed value and a case where two or more arbitrary fixed values are set alternately and repeatedly. An image data processing method comprising: 2. The image data processing method according to claim 1, wherein the selection mode setting method can be individually selected and set according to an output resolution of image data developed in a bitmap form. An image data processing method characterized in that: 3. The image data processing method according to claim 1 or 2, wherein the selection mode setting method individually selects the type of an application indicating a model that outputs image data developed in a bitmap form. An image data processing method characterized by being able to select and set. 4. Recognizing a line segment shape at a boundary portion between a black dot region and a white dot region of image data developed in a bitmap shape, a plurality of features of the line segment shape recognized for each dot. It replaces with the bit code information, determines whether the dot needs to be corrected by using at least a part of the code information, and corrects the correction data according to the code information for the dot determined to need correction. What is claimed is: 1. An image data processing apparatus comprising: a dot correction unit that outputs and corrects image data, wherein the dot correction unit forms a bit map at the same timing with respect to a signal that is generated periodically. Image data generating means for repeatedly generating the same developed image data, wherein the same image repeatedly developed by the image data generating means and developed into a bitmap form is provided. In the image data processing device in which the correction is performed for each of the image data, the number of times of repetition generation in which the same image data expanded in the form of a bitmap is repeatedly generated by the image data generation unit is set to one arbitrary number. It has a selection mode setting means which can arbitrarily select and set any of a case where a fixed value is set and a case where two or more arbitrary fixed values are alternately and repeatedly set. Image processing apparatus. 5. The image data processing apparatus according to claim 4, wherein said selection mode setting means can individually select and set the image data in accordance with an output resolution of image data developed in a bitmap form. An image data processing device characterized by the above-mentioned. 6. The image data processing device according to claim 4, wherein the selection mode setting means individually selects the type of an application indicating a model that outputs image data expanded in a bitmap form. An image data processing device characterized by being able to select and set.