JPS59189781A - Picture processing device - Google Patents

Abstract

PURPOSE:To express accurately the half tone independently of connection of reading means by providing a means which expresses outputs of plural reading means with a gradation and controlling the gradation expressing means in accordance with connection parts of reading means. CONSTITUTION:An initial value is loaded to a main scanning counter 908, which drives a dither ROM 907, by a horizontal synchronizing signal (H.SYNC) corresponding to a signal of beam detection. A counter 908-1 loads ''0'' by the signal H.SYNC to start counting and counts 0,1,2,3,0- repeatedly. A counter 908- 2 is operated similarly, but the value with which counting is started is controlled by a CPU. That is, the CPU sets data to an I/O latch 911 after automatic connection so that the load value of the main scanning counter 908-2 is ''0'' when the number of used bits inthe system of a CCD 1 is a multiple of 4 and the load value is 1,2, or 3 when said number of used bits is (a multiple of 4+1,2, or 3). Thus, the disturbance of dither patterns is eliminated near the joint between CCDs 1 and 2.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an image processing device capable of expressing gradation. Conventionally, there are devices that use a plurality of CODs to read an image, convert it into an electrical signal, and perform image processing. The applicant is C.
Regarding the automatic connection of ODs in the main rectangular direction, we proposed a method in which a marker or the like is provided in the area outside the document and compensation for connection between bits is made based on the marker.

When expressing sentence halftones, a dither method using a dither pattern memory is generally used. However, when a dithering method is used, simply connecting bits causes disturbances in the dither pattern, resulting in unnatural gradation at the connecting portions. Since the dither method attempts to express one brightness gradation with an area of 2 x 2, 4 x 4 degrees, 8 x 8 bits, etc., there are cases where the next pattern starts before one pattern ends. If this exists, accurate gradation cannot be expressed in that part, and the image will be distorted.

The present invention eliminates the above-mentioned drawbacks and reduces the unnaturalness of gradation reproduction, and controls the reading of gradation expressing means such as a dither memory in response to the joint portion. It also controls the initial value of the counter that addresses the dither memory.

FIG. 1 shows the appearance of a copying apparatus according to the present invention.

This device basically consists of two units.

They are reader A and printer B. The reader and printer are mechanically and functionally separated so that they can be used independently. Connections are made only with electrical cables. Reader B is equipped with an operation section A-1. Details will be described later.

FIG. 2 shows a cross-sectional view of the structure of reader A1 printer B. The manuscript is placed face down on the manuscript glass 3, and its placement reference is on the British side when viewed from the front.

The original is pressed onto the original glass by the original cover 4. The document is illuminated by a fluorescent lamp 2, and an optical path is formed such that the reflected light passes through a mirror 5.7 and a lens 6 and is condensed onto the surface of C0DI. The mirror 7 and the mirror 5 are arranged to move at a relative speed of 2:1. This optical unit moves from left to right at a constant speed while applying PLL using a DC servo motor. This moving speed is 180 on the outward path when irradiating the original.
mm/sea, return journey is 468ITIm/sθ
It is C. The resolution in this sub-scanning direction is 16/inθs/
IIIm. Document sizes that can be processed: A5 to A3
There are up to 100 yen, and the document placement directions are tiA5 and B5.

A4 is placed vertically, B4 and A3 are placed horizontally, and there are six return positions for the optical unit depending on the document size. 1st point Hiro A5. B5゜A4 common, 220mm from the document reference position, the second point is B4
The third point is A6 at the same < 364 mm, and the same < 4 + 1.8 mm.

Ru. In order to resolve this at 16 peg/ays, the number of hits for can is r 4752 (=297
X16) Since a human is required, try 2 with this device.
(7) Two CCD array sensors were used and driven in parallel. Therefore, 16 l! 1nes/
min, 180 a@/sea (1) From the conditions, the main scanning period (=00D accumulation time) is T=i=drift n=
347.2 psec v;b. COMM) Next, referring to FIG. 2, the outline of the printer placed under the reader will be explained. The image signal processed by the reader section and made into bit serial is input to the laser scanning optical system unit 25 of the printer. This unit includes a semiconductor laser, collimator lens, rotating polygon mirror, Fθ lens,
It consists of a tilt correction optical system. The image signal from the reader is applied to a semiconductor laser and undergoes electrical-to-optical conversion, and the diverging laser light is converted into parallel light by a collimator lens, and is irradiated onto a polyhedral mirror rotating at high speed, thereby scanning the laser light onto the photoreceptor 8. . The number of rotations of this polyhedral mirror is 2
．． It is being rotated at 60 Orpm. During scanning, it takes about 400 electres, and the effective image is 297 meters long on A4 paper.
It is. Therefore, the signal frequency applied to the semiconductor laser at this time is approximately 20 MIH1 (at the time of three-value output). Laser light from this unit is incident on the photoreceptor 8 via the mirror 24.

For example, this photoreceptor 8 has three layers: a conductive layer, a photosensitive layer, and an insulating layer.
Consists of layers. Therefore, process components are arranged thereto which make it possible to form an image. 9 is a front static eliminator;
10 is a front static elimination lamp, 11 is a primary charger, 12 is a secondary charger, 13 is a front exposure lamp, 14 is a developer, 15 is a paper feed cassette, 16 is a paper feed roller, 17 is a paper feed guide, 1
8 is a registration roller, 19 is a transfer charger, 20 is a separation roller, 21 is a conveyance guide, 22 is a fixing device, and 23 is a tray. The speed of the photoreceptor 8 and the conveyance system is the same as the forward path of the reader (180 tttm/see). Therefore, the speed when copying by combining the reader and printer is 3 on A4 paper.
The number of sheets per minute is 0. Further, printers use a separating belt on the front side to separate the copy paper that is in close contact with the photosensitive drum, but because of this, the image of the belt is missing. if,
However, if you put a signal on it, it will be developed,
The toner stains the cyvert and will also stain the subsequent paper, so the reader side is designed to cut off the video electrical signal for print output in advance to the cyvert stem. Also, if toner adheres to the leading edge of the copy paper, it will wrap around the fixing roller when it is fixed and cause a jam, so the electrical signal is similarly cut on the reader side to prevent the toner from adhering to the leading edge of the paper Ztxm width. ing. Next, Figures 14-1 and 14-2 show the main scanning directions of the reader and printer and the output images.

The reader goes from the back side to the front side, and the printer goes from the front side to the back side.

The copying apparatus of this example has intelligence such as image editing, but this intelligence is performed on the reader side by processing the signals read by the COD, and in no case is there any processing at the stage of output from the reader. Also, a certain number of bits (4
752), a signal at a constant speed (13.89MHz) is output. The function of intelligence is
Any magnification in the range of 0.5 → 2.0 times, enlarging/reducing to a specific magnification, cropping function to extract only the specified area, moving the cropped image to any location on the copy paper It has a movement function. In addition, there is a function that performs halftone processing in 32 gradations depending on the key specification.

Furthermore, it has a composite function that combines these individual intelligent functions.

Next, the functions of this example device will be explained.

In addition to a simple copying function, this device also has a variable magnification function that allows arbitrary enlargement/reduction, an editing function that allows you to extract or delete any part of the document, and also automatically detects the size and position of the document. It has various functions such as automatic scaling and editing. These functions for manipulating images of documents are collectively referred to as "image manipulation functions." In addition to making copies of original images scanned by a connected printer,
CCU (Communication Control)
The document image can be sent to another printer via the communication control unit (Unit=communication control unit). Further, it is also possible to receive a document image sent from another reader to the printer at hand. Such a function is called an "image transfer function." Furthermore, the above-mentioned selected functions can be arbitrarily registered in six preset keys. The registered contents can be specified arbitrarily by the user, and the contents are retained even when the power is turned off.

Such a function is called a "preset function."

Furthermore, there is an automatic exposure function that removes the background of the original, and a halftone processing function that outputs images with gradations such as photographs with good reproduction.

These are collectively called image quality processing functions. Organized below,
There are five image manipulation functions:

In other words, the variable magnification function is equal magnification (100% magnification), fixed magnification (100% magnification),
size specification), stepless magnification (magnification specification 50-200%)
, XY variable magnification (independent variable magnification in the main and sub-scanning directions). The image reversal function includes original image, negative/positive reversal image. Editing functions include no editing, white masking, and black masking. However, the latter two do not automatically switch to automatic XY variable magnification, and other variable magnification functions cannot be specified. White frame trimming, black frame trimming, and automatic document position detection are available. However, here, the variable magnification, image reversal, movement, and special variable magnification functions are linked. The movement functions include no movement, destination specification, origin movement (cornering), and centering. Special magnification functions include no special magnification specification, auto magnification, and auto XY magnification. However, the latter two cannot specify other scaling functions. The movement function and special scaling function are enabled only when the editing functions such as white/black frame trimming and automatic document position detection are specified.

Also, some of the image transfer functions include local copy (normal copy), transmission (sending original images to other printers via CCU), and receiving (receiving original images from other printers via CCU). be.

In addition, some of the preset functions include registration (stores in the preset key), readout (reads the stored contents of the preset key), and reset (returns all functions to standard mode).In addition, the image quality processing function Automatic exposure (AE) inside
, there is intermediate processing.

FIG. 5 is a detailed view of the operating section A-1 in FIG. 1. This operation section is divided into three main blocks. The block on the right is a general-purpose key display section 100 found in conventional copying machines. The central block is a function key display section 300 for calling up and using a copying and transmitting function that the user has created and registered arbitrarily through a program.

The block on the left is a shift key display section 200 for the user to create copy/transmission functions as desired. The general-purpose key display unit 1oo will first be described. Reference numeral 0103 is a 7-segment/) LED display for displaying the desired set number of copies and the number of intermediate copies. Reference numeral 102 indicates a warning display used in a conventional copying machine, such as jam, out of toner, out of paper, or copy interruption. Reference numeral 104 denotes a copy density switching lever and the obtained density display. Reference numeral 105 denotes a selection display for document images containing only text, only photographs, a mixture of text and photographs, and section vapor. These are provided to perform different image processing so that four types of original images can be copied in an optimized form. 106 indicates whether the selected cassette stage is the upper stage or the lower stage. Reference numeral 107 is a display device for displaying the paper size stored in the cassette of the selected cassette stage.

108 is a group of ten keys of θ~9, C, and the display 10
It is used to set the number of sheets to 3 and to enter numerical values (for example, trimming coordinates, movement coordinates, magnification of zooming, destination address designation, etc.) in the program creation process on the soft key display section 200. 109 entry keys are provided as confirmation keys for the latter 200 key entries. Reference numeral 110 indicates an interrupt key that interrupts multi-copying and performs another multi-copy operation; 111 indicates a copy cancel key that interrupts multi-copying of the printer or cancels reception; and 1o1 indicates a copy cancel key that instructs the printer to start printing or starting transmission. This is the key. 113 is a document image switching key of 105, and 112 is a cassette stage switching key. 11
3.112 shifts the selection from top to bottom every time the key is turned on. The cover of this part of the function key display section 300 is structurally removable. The reason is as mentioned above), one of the functions created arbitrarily on the soft key display area is registered and corresponds to one key 3020, so it is necessary to give the function created by yourself some name and write it on the key 302. It is necessary to include it. Therefore,
After registering the function, the user removes the cover, writes a name on one of the registered keys 302, and then puts the cover back on. That's all, function key 30
Since 6 functions are provided for 2, the user can register 6 functions. When the user creates a function on the soft key display section 200, a message asking whether or not to register it will appear on the soft key display section 202. If the user responds with the soft key 201, the function will be displayed on the function display section 300. All six indicators 303 corresponding to six certain keys perform a blinking operation. This means that the machine is asking the operator, "Which function key do you want to register the above function to?" Therefore, when the operator presses any key at this time, the display corresponding to that key lights up and the other displays go off. The operator then removes the key (-), writes the function salt on the key, and attaches the key (- again.) Since the memory of the contents registered here is backed up by the battery, it will disappear even if the power switch is turned off. There is no such thing.

Key 301 is a standard mode return key.

Incidentally, the display 114 lights up when the interrupt key 110 is turned on, but flashes when the station enters the reception mode to notify reception of image data from another station and prevent printing using the copy key 101. During reception printing, data can be set and registered using keys 200 and 300. Therefore, after receiving the print, the sentence
When the copy key 101 is turned on during reception, the received contents (sender address, total number of received prints, received print count) are displayed on the liquid crystal display 202.

This display is erased by the clear key C, and the standard mode display or the data set before the copy key 101 is turned on is displayed. If the cancel key 111 is turned on during multi-print reception, paper feeding is blocked, the print cycle for the paper already in the path is completed, and printing is stopped. The sending side displays a message to cancel on the LCD display 0 Detailed explanation of the reader unit 0 Figure 6 K +7-
The system block diagram of the data unit is shown.

The interface signals with this reader are shown on the right. When connecting to a printer, connect connector JRI to connector JPI on the printer side. When setting up a reader/printer and communicating with the outside, connect the signals originally going to connector JPI from JR1-4- to the communication control unit) (C
once in the JCI of the communication control unit (CCU).
) is connected to JPI from JC1'. In addition to this, JR2 and JC are used as protocol signals.
Connect 2. The timing of the JRI interface signal is shown in FIGS. 7 and 8.

The BEAM DETECT signal BD is used to connect the printer and synchronize with the rotation of the scanner, and corresponds to the tip signal of each line. VIDEO is an image signal,
Each pixel is output in 4752 pieces per line with a width of 55 ns. However, one pixel has three values, that is, O,"
/211 state, so 0 is 55
ns width, false is H for 2.7.5ns in the first half and 2ns in the second half.
7.5 ns length, 1 becomes 55n8 width H. This signal is BEAM, DE if a printer is connected.
It is output in synchronization with the TECT signal, and in other cases (transmission to another, etc.), it is output in synchronization with an internal pseudo signal.

VIDEOENABLE is if the image data is 4752
This is a period signal during which pits are output. This is also BEAM
It is output in synchronization with DETECT or an internal pseudo signal. VSYNC is a signal that is output in synchronization with the output of the image leading edge detection sensor 37b and BEAM DETECT or an internal pseudo signal, and means that image data will be output from now on. VIDEOENABL during signal
Same as E. The PRINT 5TART signal is a paper feed command to the printer side. This PRINT 5TAR
The time interval between T and VSYNC is determined by the control circuit in consideration of the variable magnification and the trimming area.

PRINT END is a response signal from the print side.
This is ejected when the trailing edge of the copy paper leaves the photosensitive drum and rides on the conveyor belt, indicating that the printing operation has ended. This detects the completion of copy paper separation and is issued at sequence timing. ABX C0
The NNECT signal is connected to the communication interface module 40.
Indicates that a is connected. When a communication interface module is connected, this terminal is set to GN within that module.
It is now possible to drop the signal to D, thereby enabling communication. PRINTERC0NNECT signal is PRI
This is output when NTER is connected, and this terminal should be connected to GND on the printer side. Then, the shivering is activated.

S, DATA, S, CLK, C8CBUSY
, PSCBUSY.

is a serial signal line for carrying out a protocol (allowing transmission between the two, exchanging information such as signals, etc.) between the reader and the printer. S, DATA, S.

CLK is 16-bit protocol data and a clock, both of which are bidirectional lines.

C8CBUSY is output when the reader side outputs data and a clock to the line, and PSCBUSY is output when the printer side outputs data and a clock to the line. Therefore, these are S, DATA and S, C
This line indicates the direction of LK transmission. Please refer to FIG. 8 for detailed timing.

Returning again to FIG. 6-1, the system block of the reader will be explained. CO in the CCD reading section 601, 601'
It has a built-in clock driver for D and COD, a signal amplifier from the CCD, and an A/D converter for A/D converting it. This control signal to the COD is generated by the COD control control signal generating section 603603' and the CCD reading section 601.
601' clock driver. This control signal is generated in synchronization with the horizontal synchronization signal BD from the printer. Image data converted into a 6-bit digital signal is output from the CCD reading sections 601 and 601' and input to the image processing sections 602 and 602'. This image processing section 6
02.602' includes a sampling circuit for sampling the COD output and controlling the light intensity of the light source by the CPU, a shading amount detection circuit for the light source and lens, and its correction circuit, and a circuit for each main scan to perform the AE function. Peak bold circuit that detects the peak value of light intensity, quantization that determines the slice level of the 6-bit image data after shading correction is completed based on the peak hold value or dither pattern of the previous line or the line before the previous line, and converts it into three values. It has a circuit. The image signals quantized by the image processing units 602 and 602' are input to the image editing units 604 and 604'.
This image editing section 604, 604' has a buffer memory for two lines. The capacity for one line is more than twice the number of pixels per line, 4752. The reason for this is that when enlarging by 200%, each pixel data is written to the memo IJK at twice the sampling rate, so the amount of data is doubled. Also, the reason for the buffer memory for two lines is that the memory cannot perform writing and reading at the same time, so when the N-th line of image data is being written to the first memory, the N-1 data from the second memory is being written. This is to read out the image on the first line. Also, in order to convert into three values,
The amount of information will be twice as much as above. Therefore, as the required memory system, ``8 systems of 4752 x 21 memory units are required.If we use the current memory element, 8 systems of 16-pit memory (for example, HM6116 etc.) are required. has a write address counter for writing image data into this buffer memory, a read address counter for reading it, and an address selector circuit for switching the address signals from these two counters.The counter is a parallel type whose initial value can be preset. Using a load tag, the initial value is set so that the CPU loads the I10 boat.The CPU follows the coordinate information instructed on the operation panel and updates the counter each time the sub-scan reaches the line corresponding to the trimming coordinate. Document information can be edited by presetting address values corresponding to main scanning coordinates.There are coordinate area control counters and gate circuits to enable white masking, black masking, white frame trimming, and black frame trimming. Image data from the 0 image editing section, which has a seam detection shift register for automatic seaming of COD, is first output from 604, then from 60
4', the composition unit 605 smoothly switches them to form one serial image data. The recognition unit 606 is for performing pre-scanning of the document during the idle rotation period of the printer after turning on the copy button, and detecting the coordinates where the document is placed at that time. This part includes a shift register for detecting 8 bits of continuous white image data, a % vote, and a main/sub-scanning counter. Operation unit 6
07 includes a key matrix, LED, liquid crystal, and liquid crystal driver. -1608 is a DC motor for scanning the optical system, and white 09 is its driving circuit. 610 is a fluorescent lamp for illuminating the document, and 611 is its lighting circuit.

A photo sensor 612 detects that the optical system unit is at the home position, and a photo sensor 613 detects that the optical system unit is at a position to irradiate the leading edge of the document. The CPU section 614 includes CPU ROM, RAM,
It consists of a battery backup circuit, a timer circuit, and an I10 interface. The CPU section 614 is the operation section 6
07, performs league sequence control according to operation commands from the operator, and at the same time controls the printer using commands. In addition, in accordance with instructions related to image processing from the operation unit 607, the image processing unit 6
02.602' Data is set for various counters in the image editing section 604.604'. Furthermore, CPU
The image editing section 604 controls the light amount of the fluorescent lamp lighting device 611 based on the light amount data from the image processing section prior to document scanning, and presets speed data for the DC motor drive circuit 609 according to the magnification command. .604'
Collect image stitching data from and calculate the stitching amount.

FIG. 6-2 is a flowchart of the key control of the operation unit 607 by the CPU 614. When the power switch of the reader is turned on, the shift memory, RAM, etc., which will be described later, are first reset, and the memory of the liquid crystal display 202 is displayed at the same size and edited. none,
Set positive, no transmission, lower cassette on the 100 side,
Set one sheet of text original. Set the standard mode. These are interrupt key 110 and reset key 301
The same goes when turning on 0 to determine the copy key 3), when NO, determine whether reception is received 4), and when NO, proceed to entry routine (5) for part 200.300. . After setting and registering the mode and data according to 200.300, determine whether the printer can print or not 6).
Proceed to copy key routine when possible. When the copy key is on, it is determined whether or not to send (8), and if it is not, it outputs a print start signal to the CCU (9), and when sending, it sends the destination address data and other data necessary for sending to the CCU. (10). Once in reception mode, sending and printing will be blocked even if the copy key is turned on, but the display of mode data up to that point will be saved to a certain area of memory, and the received content will be displayed on the display 202 instead. 01). Press the clear key to return to the original mode data display (Mausoleum).

While the copy key is not turned on, it is possible to make entries using the keys 200 and 300, and also to make changes therein 03). When the reception is completed (04), the process proceeds to step 3, the copy key routine, to enable copying. If you turn on the cancel key 111 in step 13, after a predetermined time,
Proceed to step 3 and cancel reception. Note that when the clear key is turned on in step 13, the data related to numbers is reset and cleared, but the mode data etc. set by the soft keys are not reset. Standardization is reset by key 301.

Sequence control will be explained according to FIGS. 9 and 7. As shown in Figure 9, there are three
position sensors 37a to 37c. Looking from the front of the reader, the optical home position sensor (signal OHP) is located on the far left side.
output), the optical system normally stops at this position. When the reader is driven, the optical system starts scanning from left to right, and the image leading edge sensor 37b is provided exactly at the reference position of the image. When the control circuit detects this sensor 37b, it outputs an image data signal (VIDEO, CLK) and also generates a signal indicating a data valid period (VIDEOENABLE) in each main scanning cycle (347, 2 μs). And the control circuit is this VIDEO
The sensor 37b starts counting the number of ENABLE signals and calculates the first number according to the cassette size or magnification of the printer.
When the count value α corresponding to the point, the second point, and the third point is reached, the optical system forward drive signal is turned off and switched to the reverse drive signal and reversed. On the way back, PRINT
A 5TART sensor 37c is provided, and when the optical system activates the sensor after reversing, the control circuit judges whether or not the specified number of copies has been scanned, and if the number does not match the specified number, it instructs the printer to feed the next sheet. PRINT to give
5TART signal is generated. Note that it is necessary to adjust the position of the sensor 37c so that T2 in FIG. 9 becomes equal to T.

According to Figure 3! 7 To explain the processing of the signal from the CCD, the 2592-bit analog signal output from the CCD is amplified by the amplifier AMP 901, A/D converted by the A/D converter 902, and converted into a 6-bit digital signal. . On the other hand, before starting copying, illuminate the standard white board,
The digital data is once written into the RAM 904.

When copying starts, shading is corrected by multiplying the RAM 904 and the current image data. (Achieved by storing the multiplication data as a table in the ROM905-1 and addressing it with image data to obtain the output.)
The image data outputted from the multiplier ROM 905 is a digital signal without shading.The dither ROM 907 for expressing halftones has an interval of 4 bits in the main scanning direction and 4 bits in the sub-scanning direction as shown in FIG. It is set so that the same weight code (6 bits) is output at intervals, and 16 types of weight codes are assigned within this 4×4=16 bit matrix. Figure 4 shows the dither ROM data, where A is 90 in Figure 3.
7-IA, 907-2A's ROM also has B as 911
This is an example of values output by the ROMs of 7-IB and 907-2H. The arrangements of A and B differ from each other in a predetermined relationship.

Therefore, a 2-bit main scanning counter 908 (for example, 5N
74L8161, etc.) and a 2-bit sub-scanning counter to output different weight codes by addressing this dither ROM 907.

Further, there are a plurality of combinations of weight codes set in this 4×4, and the reproducibility of the halftone image can be changed depending on the combination.

The selection of this combination is performed by the I10 latch 910, and the preset to this latch is
Performed by U614. When the operator wants to make the image density lighter or darker, the operator sets the instruction using the density knob 104 on the operation panel, and the CPU sets a preset value corresponding to the value of the density knob in the X10 latch 910. do. Since the dither ROM 907 contains a plurality of dither patterns whose shading can be changed based on the set data, an image with the set density can be obtained.

Incidentally, the comparator 906 for binarization has a plurality of comparators (A series and B series) so that one pixel can be compared at the same time using two value thresholds in two ROMs. This realizes ternarization of images. By simultaneously binarizing one pixel using different thresholds of dither ROMs 907-IA and 907-IB (or 907-2A and 907-2B), 1) Both A and B are image Data > ROM Dat
a1i) A, 13 only one is image data > ROM
Dataiii) Both A1B Image Data≦R
Three types of density (referred to as ternary values) states called OM Data can be reproduced. And the parallel 2-bit image signal is
Shift memories 57-1 (g), 57-1 (
When the signal is input to B), processed in parallel, and output to the printer, it is divided into the first half and the second half of one pixel, modulated during pulses, and output to the printer. The beam of the laser of the printer is modulated by this pulse width modulation output, and is modulated in a circular shape. Therefore, 32 gradations of density can be achieved in 166 pixels. Therefore, many gradations can be realized with a small pattern, making it possible to improve the reproducibility of halftones without significantly deteriorating the reproducibility of characters. The same applies to multi-level dithers higher than three-level dithers. In addition, since the dither ROM 907-1 drives both A and B in parallel, there is no need to increase the address speed of the ROM, and it can be realized at the conventional processing speed.

By the way, since an image area can be specified using the soft keys and numeric keys in Fig. 5, only the necessary parts are reproduced with the ternary dither output, and the rest are reproduced via one dither ROM or simply 2-level dither output without passing through the dither ROM. It can also be a value reproduction.

That is, when performing ternarization dither processing only within an area specified by a key, the CPU outputs a pattern at the same level as each element to the latch 910 until the main and sub-scanning counters reach the coordinates corresponding to that area. Binarization processing is executed outside the area. When the CPU determines that the coordinates have been reached, it outputs a predetermined array pattern to the latch 910 and executes ternary dither processing. In this way, the resolution of characters, etc. outside the area can be extremely improved, and the gradation inside the area can be increased. Note that the above processing can be changed by automatically recognizing the character area.

In Fig. 10, the outputs of the shift memories (1) % (1)' are output simultaneously, but the AND gate allows (,
1) The OR gate is converted to output 1 when both outputs of % (1)' are 1, 0.5 when only one is 1, and 0 when both are 0. Shift memo') (
The same applies to 2)% <2)', and the corresponding measures can be taken even if multiple CODs are connected.

In addition, each shift memory has an address selector (1), (2)
Writing or reading of the write address, address counter, and read address counter is controlled by the register preset through the register preset. By register presetting by the CPU, the timing of writing to or reading from memory can be determined and changed. The memory has a capacity for two lines of COD so that it can be changed. Therefore, it is possible to change the printing position when setting the key data. Therefore, multilevel dither output can be used for editing processing.

In addition, masking and trimming can be performed by partially applying a gate to the output of the OR gate using the AND gate at the next stage.

(COD seam correction) A method for automatically splicing two CCDs (main scanning direction) will be described.

As shown in FIG.
Normally, when the optical system is at the home position and the light source is turned on, this white plate is illuminated and the reflected light is input to the CCD. Therefore, when the control circuit is at the home position, it corrects the variation in the amount of light and the variation in sensitivity of the two CCDs (shading correction). Further, a black line Bt having a width of 2 square meters and long in the sub-scanning direction is provided at the center of this white plate. It is sufficient that this thin line has a size that is an integral multiple of quantization. Similarly, when the optical system is at the home position, this black line appears on the bits at the ends of each of the two CODs by turning on the light source, so these CCD signals are input to the shift memory, and the CCD1 system The lower 128 bits of the signal and the upper 128 bits of the CCDz system signal are compared. It is confirmed that each of these 128-bit data always has white pits before and after, and that black bits are sand inches. Then, the number of bits obtained by adding the number of lower white bits of the CCDI system and the number of upper white bits of the base and the number of black bits is the shift value of the CCD2 system.
Thinned when reading from memory. In the figure, the CCD arrow indicates the main scanning direction, and the sub-arrow indicates the sub-scanning direction.

A specific method is shown in FIG. In order to write the image signal to the shift memory, shift memory 57-1.57-
Since static RAM is used for 2, the write address and
counter (write address counter 63) and read address counter (read address counter 6)
4°65). Since the amount of information input to the COD differs depending on the magnification, in this example, first, the write address counter (1) of the CCD 1 system is counted up from the LSB, and the input clock φ is counted up.

Count and check at what count it stopped. This is stored in the RAM of the CPU. If the magnification was the same, it would have stopped at 2592 counts. Then c
In order to extract the upper 8 bits of the cDl system (the first bit that appears in main scanning is the MSB) and the lower 8 bits of the CCDZ system, the confirmed value is input to the write address counter 63 of the CCD1 system. 08H (hex code 08) is set in the address counter of the C0D2 system, and the down count mode is specified. On the other hand, each CCD
An 8-bit shift register is provided which inputs the image signal from the CCD, and the drive period of this shift register is set at the same time as the rise of the VIDEOENABLE signal indicating the CCD0 main scanning period.
By setting the ripple carry of the counter (driven by the clock output during the VIDEO ENABLE period) to the ripple carry, the CCD1 system shift register has the CC
The image signal of the most significant 8 bits of the D1 system remains in the shift register of the CCD2 system. The values remaining in these shift registers are then read by the CPU and stored in memory. Next, the top 9 of C0D1 series
~16 bits. In order to extract the lower 9 to 16 bits of the CCD2 system, the write address counter of the CCD1 system is set to (the confirmed value - 8), and the write address counter of the CCD2 system is set to Set IOH to
Thereafter, the data is read out using the same method as described above. This operation is repeated one after another, and the upper 128 bits of the ccDl system, CCD2
After developing the lower 128 bits of the system into memory, the number of black pits, the number of lower white bits of the CCDI system, and the number of upper white bits of the C0D2 system are calculated. Then, continuity in the main scanning direction is achieved by thinning out the number of bits, which is the sum of the number of lower white bits of the CCDI system, the number of upper white bits of the CCD2 system, and the number of black bits, when reading from the shift memory of the CCD2 system.

Next, the operation of the shift memory after the continuity logic is established will be explained. When writing to shift memory, CCD1 system and CC
The D2 system write address counter is preset with the confirmed value at which count it stopped, and the shift memory is addressed and written in the down count. Since it is located 148.5 points from the center of the black thin line (1.5 mm width), which must be considered when reading from the shift memory, the read start address of the CCDI shift memory is (lower Number of white bits) + (Number of black bits/
2) + (148, 5 x 16 x magnification). C0D
The read start address of the 2nd system is (the above confirmed value)
- (number of splice bits). and 13.89M
With a read clock of 4752 pulses at Hz, first C
The read address counter (1) of the CD1 system is run by counting down, and when it reaches 0 and a ripple carry occurs, the read address counter (2) of the C0D2 series is run by counting down.

FIG. 10 shows a circuit diagram related to these shift memories.

The shift memory (1) is a static memory into which ccDl-based image data is stored. The shift memory (2) is a static memory into which CCDZ-based image data is entered. The write address counter 63 stores the address when writing data to shift memories (1) and (2).
It is a counter. The read address counter (1) is an address counter when reading data from the shift memory (1), and the read address counter (2) is an address counter when reading data from the shift memory (1).
) is the address when reading from shift memory (2).
It is a counter. The address selector (1) is
The address selector (2) selects either the address signal of the address counter 63 or the address signal of the read address counter (1) to address the shift memory (1), and the address selector (2) selects the address signal of the read address counter (1).・Address signal of counter 63 and read address・
This is for selecting one of the address signals of the counter (2) to address the shift memory (2). The shift register 74 is a register for taking out image data of the CCDI system 8 bits at a time from the lowest order, and the shift register 76 is a register for taking out image data of the CCD2 system 8 bits at a time from the most significant. F
/F73 is an F/F that is set at the rising edge of the VIDEOENABLE signal and reset at the ripple carry of the write address counter 63, and is used to control the period of input to the shift register 74.1'IJ, F/F75 is an F/F that is set at the rising edge of VIDEO ENABLE O and reset at the ripple carry of the read address counter (2), and is used to control the period of input to the shift register 76. The I10 port 72 is an Ilo for the CPU to read and confirm how far it has counted when the write address counter 63 is up-counted. I10 registers 66 to 69 are write/
Address counter 63, read address counter 6
These registers are for the CPU to give preset values to 4 and 65, respectively. The engineering 10 register 68 is a write address counter 63 and a read address counter 6.
5 is for the CPU to specify whether to count up or down, and address selectors 70 and 71 are for the CPU to specify which counter value to select, read address counter (2). The light clock (Rikishima) is used to decide whether to operate using the read clock, and the CPU is used to transfer one line of image data from the CCD driver circuit to the shift memory circuit by giving a treat signal when performing splicing. 0 According to this circuit diagram, in order to perform splicing, the image data of the CCDI system is taken 8 bits from the lowest order, and the image data of the CCDz system is taken 128 bits from the most significant 8 bits. Explain the action of releasing the button.

-The CPU first puts the write address counter 63 into up-count mode and sets the I10 register (1) to 0. ■By giving one pulse as the TE8T signal (corresponding to machine start) of the I10 register (4), one 0VIDEOE is output from the COD driver in Figure 10.
NABLE, a φ2 clock corresponding to the magnification is generated and given to the data shift memory. ■Input write address counter 63 from I10 port to CPIII
E and enter 0■Write address counter 63 to down count mode, read at Vs counter (2)
7 to down count mode, set the value stored in Ilo register (1) in ■, and set I10 to
Set 7H in register (8). ■TEST
VIDEOENABL'li gives one signal to the signal.
When the 8 bits of shift registers 74 and 76 are used up, take them into memory 1) in sequence and store them in memory 0■I10 Register (1) is set to (■'s (direct -7H)) and Ilo register (2) is set to tOH. Perform ■■.■ Do the same below and set it to I10 register (1) (value of ■ - 77H)
Set 7 and FI (in the I10 register (2,), give the TEST signal, and repeat until the shift registers 74 and 76 are read. The above seam correction is described in the specification of Japanese Patent Application No. 128073/1983 by the same applicant. Familiar with books.

In this way, pixel connections in the main scanning direction can be realized. However, since the dither pattern is repeated in units of 4 bits, if left as is, the repeating pattern will be disturbed at the junction between CCD1 and CCD2, resulting in unnatural gradations. To explain how to solve this problem, in Fig. 3, dither RO
A main scanning counter 908 (for example, 5N74L) that drives M
8.161 etc.) is a horizontal synchronizing signal (H, 5YNC) that operates with the video CLK (write clock φ2) and corresponds to the beam detection signal that indicates the start of one scan line of the laser beam.
) the initial value is loaded. CCD1
The main scanning counter 9Q8-1 that controls the system is H,5YN
Load “0” in C, start counting, “0”, “
1”.

2” “3II”, “0”, “1”, “2”...
Reply to me.

However, the main scanning counter 908 that controls the two CCD systems
-2 also starts counting from H, 5YNC, but
At this time, the value at which counting starts, that is, the initial value loaded into the υ counter by 9H, 5YNC, is controlled by the CPU. After performing the automatic connection mentioned above, the CcD
When the number of bits used in the l system is exactly a multiple of 4, the load value of the main scanning counter 908-2 is 0. 4Tsuchi 911
Set data to . Besides, CCDI, C0D2
There is no disturbance of the dither pattern near the joint of
It is possible to output smooth images. It means that the connection between Sidiza has been completed.

Also, the dithering when changing the magnification is also CCD.
This can be done depending on whether the number of bits used in one system is a multiple of 4 plus or minus several bits. The scaling can be achieved by using the write clock φ, obtained by dividing the COD clock φ.

Also, although we explained using a 4 x 4 bit dither matrix, 2
Dither patterns can be connected in a similar way with matrices such as ×2, 8×8, etc.

[Brief explanation of drawings]

FIG. 1 is a perspective view of an image processing device to which the present invention can be applied;
Fig. 2 is a sectional view of the device shown in Fig. 1, Fig. 3 is a circuit diagram for binarizing the image signal input from the CCD, Fig. 4 is a dither ROM pattern diagram, and Fig. 5 is the operation section. The plan view, FIG. 6 is a circuit block diagram of the image processing device, FIGS. 7, 8, and 9 are operation time charts of FIG. 6, and FIG.
It is a block diagram of an image processing unit, and 907-IA, 9 in the figure
07-IB is dither ROM. 906-IA, 906-IB are comparators, 57-1
(4), 57-1(B) are shift memories, 910 is a dither patter/latch, and 908-1, 908-2 are main scanning counters. J,! mji C viscera I-jida6e6N)-

Claims (3)

[Claims] (1) a plurality of reading means for reading the original image and converting it into an electrical signal; a means for expressing the output of the reading means in gradation; and a means for expressing the output of the reading means in gradation; What is claimed is: 1. An image processing device comprising: means for controlling the expressing means, and capable of accurately expressing halftones regardless of the connection of the reading means. (2) The image processing apparatus according to item 1, wherein the control means sets and controls an initial value of a counter that addresses a dither memory used for gradation expression. (3) In item 1, an image processing device that enables connection and corresponding control regardless of scaling processing.