JPH05316306A - Picture recording method and its device - Google Patents

Abstract

PURPOSE:To improve the total processing speed when a picture original continuously read an image is formed and outputted CONSTITUTION:A size of a picture original read from an automatic original feeder is detected and when the size is less than a half of a capacity of a memory section 158, the memory is divided into two as planes A, B, first picture data are written onto a plane A and 2nd picture data are written on a plane B. Just after an output of data of a black component being final color component of the initial picture data is started, 3rd picture data are read on the plane A.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an image recording method and apparatus therefor, and more particularly to an image recording method and apparatus for improving the image recording speed of an image recording apparatus having a page memory.

[0002]

2. Description of the Related Art Conventionally, in an image recording apparatus which has a page memory and which records an image on a recording sheet by forming a latent image on a photosensitive drum by a laser beam based on image information read in the page memory, The writing start address is fixed, and if the original is smaller than half the maximum original size,
DF (Automatic Document Feeder)
Image data was input and output to the same address in the memory even when read continuously due to the above.

[0003]

However, in the above-mentioned conventional example, in the case of continuously reading and writing image originals having a size less than half the memory size, the last image output is started until the last image output starts reading from the memory. The next image document could not be written to the memory because it may be erased. As a result, a certain amount of waiting time occurs, and the recording paper that is being output is conveyed during that time, so the distance between the two recording papers is widened until the recording paper for recording the next image original is fed. .. This is especially true for ADF (Automati
c Document Feeder: An automatic document feeder) was used to read image documents continuously to form an image, and the processing speed was slow.

In order to explain this concretely, in the case where the reader unit and the printer unit of the color copying apparatus equipped with the automatic document feeder (ADF) are operated, for example, the image memory unit corresponds to A3 full page. Consider a case where a memory having a capacity for storing image data to be stored is used and A4 paper is continuously used at high speed using ADF. In addition, such a color copying apparatus has a magenta (M), cyan (C),
It has an image forming unit corresponding to each color component of yellow (Y) and black (K) and a photosensitive drum, and the recording paper is conveyed in the sub-scanning direction of the laser light of the built-in laser printer. ..

In this case, a sub-scan enable timing chart as shown in FIG. 12 can be drawn. That is, one image image is written to the memory at the timing when the signal WPE is turned on, the print paper passes through the image forming portions of M, C, Y, and K of the printer unit, and M,
The image data is read from the memory at the timings when the signal MPE, the signal CPE, the signal YPE, and the signal KPE are turned on for the respective colors of C, Y, and K. continue,
The same sequence as the second and third sheets is repeated. Figure 1
In FIG. 2, d ₁ is from the paper edge sensor that detects the leading edge of the print paper and sends a sub-scanning synchronization signal when the video signal is sent from the reader section to the printer section to the center of the photosensitive drum of the magenta (M) image forming section. , D ₂ , d ₃ , and d ₄ are the distance between the photosensitive drum for magenta (M) and the photosensitive drum for cyan (C), the photosensitive drum for cyan (C) and the photosensitive drum for yellow (Y), respectively. And the distance between the photosensitive drum for yellow (Y) and the black (K).

However, when the image data is written in the memory, if the data is always written from the same address in the memory, as shown in FIG. 12, when reading the first and second originals, K (black ) A paper interval must be provided for a distance (l ₂ ) corresponding to the time immediately after the start of output of the color components. Assuming that the distance that the paper is conveyed in the time until the writing of the image data to the memory is completed is l ₁ , the following relationship is always satisfied: l ₁ + l ₂ = d ₁ + d ₂ + d ₃ + d ₄ + d ₅ , d ₅ ≧ 0 (1) l ₂ ≧ d ₁ + d ₂ + d ₃ + d ₄ (2) needs to be satisfied. Therefore, the distance between the drums (d ₂ ,
The copy speed is limited due to d ₃ and d ₄ ). Therefore, when continuous copying is performed using the ADF, the increase in copy speed is hindered even if there is a margin in the image memory capacity due to the limitation due to the distance between the drums (d ₂ , d ₃ , d ₄ ). was there. The present invention has been made in view of the above conventional example, and an object of the present invention is to provide an image recording method and an apparatus for improving the image recording speed.

[0007]

To achieve the above object, the image recording method of the present invention comprises the following steps. That is, a step of reading a document image, a step of generating data indicating the size of the document image, and based on the data, when the size is a predetermined size, the image memory is divided into a plurality of areas and divided. A step of sequentially writing image data corresponding to different original images in the plurality of areas,
A step of sequentially reading the image data from the divided areas of the image memory and forming an image on each of different recording media.

According to another aspect of the present invention, reading means for reading an original image, storage means for storing image data read by the reading means, data indicating the size of the image original is generated, and the data is stored as the data. Comparing means for comparing the amount of image data that can be stored in the storage means,
Based on the comparison result by the comparison means, when the size is a predetermined size, the storage means is divided into a plurality of areas, and the plurality of divided areas are sequentially provided with image data corresponding to different document images. An image recording apparatus comprising: writing means for writing; and image forming means for sequentially reading the image data from the divided areas of the storage means to form images on different recording media.

[0009]

With the above construction, the present invention generates data indicating the size of an original image, and based on the data, when the size is a predetermined size, the storage means is divided into a plurality of areas and divided. It operates so as to sequentially input and output image data to a plurality of areas.

[0010]

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

FIG. 4 is a block diagram showing the arrangement of a color image recording apparatus for reading an original and recording it on recording paper, which is a typical embodiment of the present invention. In FIG. 4, a color image recording apparatus includes a document reading unit (hereinafter referred to as a reader unit) 101,
It is composed of an ADF (Automatic Document Feeder) unit 102 and a printer unit 103.

<Structure of Reader Unit> FIG. 1 shows a reader unit 101.
3 is a block diagram showing the configuration of FIG. The reader unit 101 has a copy start key 1102 for instructing copying of an original and keys 1103, 1104 for specifying the original size, which specify A3 size and A4 size, respectively. The signals of these keys are input to the CPU 31 via an I / O unit 32 described later.

In FIG. 1, a document image is read by a CCD 151 provided with a filter of three colors of RGB, and A /
The D & S / H unit 152 converts the image data into digital data in which each color component is composed of 8 bits, and the shading correction unit 153 and the input masking unit 154 correct the image data. In the scaling function, the scaling unit 155 performs scaling processing. Next, the companding unit 156 once stores the image data having three color components (RGB), and the masking / U
The CR unit 160 performs masking processing. Further, YMCK output image data is created by the γ correction 161 and edge enhancement 162, and the printer 10 is processed through the video processing unit 163.
At 3, the image is recorded on the recording paper. The video processing unit 163 processes the YMCK video signal sent via the reader unit 101 to generate a PWM modulated laser light signal.

<Printer Configuration> The printer unit 103 includes
As shown in FIG. 4, a polygon scanner 301 for scanning the photosensitive drum with laser light generated in the video processing unit 163, a first-stage magenta (M) image forming unit 302,
There are image forming units 303, 304, and 305 for each color of cyan (C), yellow (Y), and black (K) with the same configuration.

In the image forming unit 302, 318 is a photosensitive drum which forms a latent image by exposure to laser light.
13 is a developing device for developing toner on the drum 318, and 314 in the developing device 313 applies a developing bias,
A sleeve for developing toner 315 is a primary charger for charging the photosensitive drum 318 to a desired potential.
Reference numeral 17 is a cleaner for cleaning the surface of the drum 318 after transfer, and 316 is the drum 3 cleaned by the cleaner 317.
Reference numeral 330 is an auxiliary charger that removes the charge on the surface of 18 so that the primary charger 315 can obtain good charge, 330 is a pre-exposure lamp that erases the residual charge on the drum 318, and 319 is the transfer belt 306. Is a transfer charger for discharging the toner image on the drum 318 to the transfer member by discharging from the back surface of the transfer member.

Reference numerals 309 and 310 are cassettes for accommodating transfer members of different sizes, for example, A3 size and A4 size papers, and 308 is a paper feeding section for supplying the transfer members from the cassettes 309 and 310. Is the paper feed unit 3
Reference numeral 312 denotes an attraction charger that attracts the transfer member fed by 08 onto the transfer belt 306.
The transfer belt roller is used for the rotation of the transfer belt 306 and is paired with the adsorption charging device 311 to charge the transfer member to the transfer belt 306 by adsorption.

Numeral 324 is a charge eliminating charger for facilitating the transfer member to be nucleated from the transfer belt 306, and numeral 325 is a peeling charger for preventing image disturbance due to peeling discharge when the transfer member is separated from the transfer belt. , 326, 327
Is a pre-fixing charger that compensates for the toner attracting force on the transfer member after separation and prevents image disturbance, and 322 and 323 are for statically initializing the transfer belt 306 by discharging the transfer belt 306. 328 transfer belt static eliminator charger
Is a belt cleaner that removes dirt on the transfer belt 306.

307 is separated from the transfer belt 306,
This is a fixing device for thermally fixing the toner image on the transfer portion recharged by the pre-fixing charging devices 326 and 327 onto the transfer member.

Reference numeral 329 is a paper leading edge sensor for detecting the leading edge of the transfer member fed onto the transfer belt by the paper feeding portion 308. The detection signal from the paper leading edge sensor is sent from the printer portion to the reader portion, and the reader portion is read. It is used as a sub-scanning synchronizing signal when a video signal is sent from the printer section to the printer section.

<Main Block Configuration of Reader Unit> Returning to the reader unit 101, the companding unit 156 compresses the RGB image data subjected to the scaling process by the encoder unit 157. For example, consider the portion of the thick frame hatched portion shown in FIG. Here, it is assumed that one rectangular cell corresponds to one pixel, and each pixel has data of three colors of RGB of 8 bits. Such data is 4 pixels × 4 lines, that is, data of 16 pixels (16 pixels × 3 colors × 8 bits = 384 bits) is set as 1 block (corresponding to the shaded portion of the thick frame), and L ^* a ^* b ^* Convert this 3
The 84-bit data is compressed to 1/12 to be 32-bit data. This is stored in the memory unit 158 as image data (A) 208. Each of the decoder units 1 corresponding to each color component of YMCK is used for simultaneous processing of four colors.
It is sent as image data (B) 209 to 59, and data of each YMCK color component is expanded to 24 bits. At this time, the memory unit 158 has a memory space corresponding to the read original or recording paper, and as shown in FIG. 3, the image memory 201 (32-bit data is stored in the same address space accessible by one address counter 204). ) And a bitmap memory 202 (1 bit). Although the image memory 201 and the bitmap memory 202 are described as DRAMs in this embodiment, other storage elements or devices may be used.

The image memory 201 and the bit map memory 202 have a common address bus, and the address counter 204 regards 4 pixels × 4 lines as one unit and considers one address in the memory space. At the address, the compressed 32-bit data described above is transferred to the W indicated by 501 in FIG.
It is stored according to the timing when the E (Write Enable) signal turns on, and MC is stored as in 502 to 505.
Reading is performed according to the timing when the timing signal of each YK color component is turned on.

Here, one unit of image data (4 pixels × 4
(Line) is time-divided into 8 blocks as shown in FIGS. 6 to 7, and writing of image data to the memory and timing of reading each color are determined in advance for each block, and the memory is independently stored in each block. Consider a system for accessing space addresses.

At this time, as shown in FIG.
8 to 87, the CPU (not shown) latches the initial value in the main scanning direction. For example, 000 _H , 810 _H , 020
_H , 830 _H , 040 _H , 850 _H , 060 _H , 870
Suppose _H is latched. Here, the subscript H indicates hexadecimal notation.

Next, the selector 88 is time-divisionally shown in FIGS.
As shown in FIG. 7, the initial value that is latched for each block is selected. Further, the counter 89 sets the count value to 000 _H by the synchronization signal Lsync at the beginning of each line and sets it to 4
Counting up for each pixel, adder 2
XADR is output by adding and subtracting two values. At this time, if the most significant bit of each initial value is the XOFF signal, and it is addition when it is "0" and subtraction when it is "1", the block a counts up as 000 _H , 001 _H , 002 _H. , Block b is 010 _H , 00F
_H , 00E _H ... count down, and so on.
Block h counts down to 070 _H , 06F _H , 06E _H ....

Next, in the same manner as shown in FIG.
97 also causes the CPU to latch the initial value in the sub-scanning direction,
Similar to the main scanning direction, the most significant bit is the YOFF signal, and if it is "0", the adder 108 is added,
If "1", subtract. Next, the counter 99 is cleared together with the RST signal when the power is turned on, and counts up by one every four lines until the power is turned off. Then, the initial value Y ₀ and the count value C ₁ of the counter 99 are added to the adder 1
00 to 107, and the calculated value Y ₀ ± C ₁ is latched by the latch signals 110 to 117 by the synchronizing signals PS0 to PS7 at the rising edge of the enable signal in the sub-scanning direction in FIG. To do. This is time-divided by the selector 98, and the calculated value Y ₀ ± C ₁ is output.

Further, the calculated value Y ₀ ± C ₁ latched by the adder 108 and the counter value C ₂ that is updated every four lines are added and subtracted to obtain YADR = Y ₀ ± C ₁ ± C ₂ . That is, when YOFF = “0”, YADR = Y ₀ + (C
_2- C ₁ ), when YOFF = “1”, Y ₀ − (C ₂ −
C ₁ ) and the initial value Y ₀ and the actual count value (C ₂ −
The value obtained by adding and subtracting C ₁ ) and is output from YADR.

Next, as shown in FIG. 10, the CPU sends XADR and YADR for each of the blocks a to h shown in FIG.
Signal XYCHG (when it is "0", XADR
And YADR are output as they are, and when "1", X
Switch ADR and YADR) to CPU 41 in latch 41
Are input in advance from each block and selected by the selectors 43 and 44 for each block, and the D flip-flop 4
After 5 and 46, XMA is output as an address in the main scanning direction and YMA is output as an address in the sub scanning direction.

The three signals of the XYCHG signal, the XOFF signal, and the YOFF signal described above are added to the D flip-flop 4.
7 to 49, the signal ROT is synchronized with XMA and YMA.
<0>, ROT <1>, ROT <2> are obtained.

The 3-bit ROT signal produces the image shown in FIGS. 11 (a) to 11 (h).

<Divided Use of Memory Unit> Next, the automatic document feeder (ADF) 102 is equipped and the reader unit 1 is used.
01 and the printer unit 103 are operated, for example, the case where the memory unit 158 is a memory capable of storing image data corresponding to A3 full pages and A4 sheets are continuously used at high speed using the ADF 102 will be considered.

In this embodiment, when the ADF 102 detects that the document size is A4, the memory unit 158 having a capacity corresponding to the full page A3 is automatically stored in the full page memory (A3) as shown in FIG. Minute) is divided into two parts, which are referred to as surface A and surface B, respectively. Then, the odd-numbered originals are input and output to the A side, and the even-numbered originals are input and output to the B side. In this way, the timing chart is shown in FIGS.
3 and l ₂ can be made small. That is, since the memory unit 158 is divided into two, the formula (1) becomes 2 (l ₁ + l ₂ ) = d ₁ + d ₂ + d ₃ + d ₄ + d ₅ , d ₅ ≧ 0 (3), and l ₂ ≧ It suffices if the condition of (d ₁ + d ₂ + d ₃ + d ₄ ) / 2 −l ₁ (4) is satisfied, and the space between sheets becomes considerably small.

However, when the image data is stored on the A side and when the image data is stored on the B side, the offset value of the sub-scanning direction address must be changed at each timing. Therefore, in this embodiment, as shown in FIG. 15, in the CPU 31, five sub-scan enable signals (WPE, MPE, CP) are supplied through the I / O unit 32.
(E, YPE, KPE) is monitored, and the latches 90 to 97 are latched at the rising edge of the sub-scan enable, and the latches 110 to 117 are immediately latched. If you do this,
By the time the next sub-scan enable is activated, the CPU 31 sets the start address of the next B side in the case of the A side, and sets the start address of the next A side in the latches 90 to 97 in the case of the B side. Since it is good, the processing of the CPU 31 can be executed with a considerable margin.

Therefore, according to the present embodiment, there is a memory for storing image data corresponding to A3 size, and when a plurality of image originals of A4 size or smaller are continuously read to form an image and print out, Since the document size can be detected and the memory can be divided and used to accommodate the image data, the waiting time between the image documents can be shortened, and image printing can be continuously performed at high speed.

In this embodiment, the memory unit 158
However, the present invention is not limited to this. For example, if the memory is divided into four postcard sizes as shown in FIG. 16 and the image data output from each of the divided memories is sequentially transferred to the recording paper in the same manner, the distance between the recording papers is further reduced. Higher speed can be realized. Note that in FIG. 16, 401 to 404 are Y
It is a photosensitive drum corresponding to each color of MCK.

Further, continuous A4 page copying (for example, the image original of A3 is read and divided into right and left, and each of them is A4.
In the case of outputting on a print paper of a size), conventionally, the image original is read by scanning twice, but according to the present invention, the image original of A3 size is scanned by one scan at the timing shown in FIG. Read (eg A3
By outputting the left half of the document on the A side and the right half on the B side), the speed can be increased even during continuous page copying.

In the present embodiment, the document size is detected by the ADF 102, but the present invention is not limited to this, and the keys 1103, 1104 of the reader unit 101 can be used.
It may be document size information designated by. Although the printer shown in FIG. 4 is used as the printer in this embodiment, the present invention is not limited to such a printer, and the same applies to other printers such as a thermal printer and an inkjet printer. can do.

The present invention may be applied to a system composed of a plurality of devices or an apparatus composed of one device. Further, it goes without saying that the present invention can be applied to the case where it is achieved by supplying a program to a system or an apparatus.

[0038]

As described above, according to the present invention, the storage means for automatically storing image information according to the detected size of the image original is divided into a plurality of storage means, and the divided storage means sequentially stores images. By repeating the input / output of information, there is an effect that an image can be formed and output at high speed. This effect is remarkable when performing continuous reading and continuous output using, for example, an ADF (Automatic Document Feeder).

[Brief description of drawings]

FIG. 1 is a block diagram showing a configuration of a reader unit of a color image recording apparatus.

FIG. 2 is a schematic diagram showing 4 pixels × 4 lines of image data to be compressed.

FIG. 3 is a block diagram showing access to a memory unit.

FIG. 4 is a block diagram showing a configuration of a color image recording apparatus that is a typical embodiment of the present invention.

FIG. 5 is a timing chart of a sub-scanning enable signal.

[Figure 6]

FIG. 7 is a diagram showing a time-division process of access to a memory unit.

FIG. 8 is a main scanning direction address counter circuit diagram.

FIG. 9 is a sub-scanning direction address counter circuit diagram.

FIG. 10 is a block diagram showing a circuit configuration of a main / sub address counter output and a ROT signal.

FIG. 11 is a diagram showing an example of an output image due to a difference in ROT signal.

FIG. 12 is a timing chart of the enable signal in the sub-scanning direction when there is continuous memory data input / output according to the conventional image recording apparatus.

FIG. 13 is a timing chart of enable signals in the sub-scanning direction when image data memory input / output is continuously performed.

FIG. 14 is a diagram showing division of an image memory.

FIG. 15 is a block diagram showing a state detection circuit for an enable signal in the sub-scanning direction.

FIG. 16 is a diagram showing a relationship between data output from the image memory and a conveyance state of recording paper when the image memory is divided into four.

FIG. 17 is a timing chart of an enable signal in the sub-scanning direction when there is continuous page shooting.

[Description of Reference Signs] 31 CPU 32 I / O Port 41, 80 to 87, 90 to 97, 110 to 107 Latch 42 to 44, 88, 98 Selector 45 to 49 D Flip Flop 89, 99 Counter 91, 100 to 108 Adder 101 Reader unit 102 ADF (Automatic Document Feeder) unit 103 Printer unit 156 Companding unit 157 Encoder unit 158 Memory unit 159 Decoder unit 201 Image memory 202 Bitmap memory 203 Image editing unit 204 Address counter 206 to 207 RAS / CAS / WE generation unit 208 Image data (A) 209 Image data (B) 210 Setting data by CPU

Claims (2)

[Claims] 1. A step of reading a document image, a step of generating data indicating a size of the document image, and based on the data, when the size is a predetermined size, the image memory is divided into a plurality of areas. A step of sequentially writing image data corresponding to different original images in the divided plurality of areas, and sequentially reading the image data from the divided areas of the image memory to form images on different recording media. And a step of forming the image recording method. 2. A reading unit for reading an original image, a storage unit for storing the image data read by the reading unit, an image for generating data indicating the size of the image original, and an image that can be stored in the data and the storage unit. Comparing means for comparing the amount of data, based on the comparison result by the comparing means, when the size is a predetermined size, the storage means is divided into a plurality of areas, sequentially into the plurality of divided areas, A writing means for writing image data corresponding to different original images; and an image forming means for sequentially reading the image data from the divided areas of the storage means to form images on different recording media. An image recording device characterized by.