JPH09261383A - Image forming device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To save paper sheets and to improve operability, functionality and copy productivity by judging the co-existence of a one-surface original and a both-surface original when they are co-existing and printing and outputting it. SOLUTION: An original bunch where the one-surface and the both-surface originals are co-existing is arranged in a circular original transmitting device RDF(recycling document feeder) and a front surface original image is recorded in a disk. Then, the original is turned-over by RDF, a back surface image is read so as to be transmitted to an image presence or absence judging circuit 307 and presence or absence of the original is given to a control part 30 from the eight-bit signal of image data. At the time of image presence, an instruction is executed so as to write binary image data in an image storage part 304 or transfer it to a printer part. The reading completed original is turned-over again and returned. The procedure is executed till the original runs out. Both- surface or one-surface printing is executed for an indicated number by a sort function at the point of time when the original runs out.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an image forming apparatus such as a digital copying machine having an electronic sort function.

[0002]

2. Description of the Related Art Recent high-performance copying machines are equipped with a double-sided copying function, and the image reading section of the copying machine having this double-sided copying function is provided with a circulating automatic document feeder or the like. Both sides of the image can be read individually. In addition, a printing unit of a copying machine having a double-sided copy function has a built-in mechanism that reverses a print sheet that has been once printed out, re-feeds the sheet, and prints on the back side of the sheet.

Therefore, the user specifies whether the original is a single-sided original or a double-sided original, and further specifies whether the print output is double-sided printing or single-sided printing, and then the copy start button is pressed. Push.

On the other hand, it has a function of reading images of all originals to be copied, temporarily storing the image data in a memory such as a hard disk, repeatedly reading out image data of an arbitrary original from the memory, and printing out. Digital copiers are known. As a result, even if the copying machine does not have a sorter device having a plurality of bins, it is possible to distribute the copy sheets in a sorted state. In addition,
This function is hereinafter referred to as "electronic sort".

[0005]

However, in the above conventional copying machine, when a single-sided original and a double-sided original are mixed in a plurality of originals to be copied, the user first
A single-sided original and a double-sided original are separated, and a copy operation is performed for each. And after sorting them out,
Further, there is a problem in that the prints are rearranged in the original order.

For example, if there are 10 originals in total, the first 5 of them are single-sided originals, the next 3 are double-sided originals, and the last 2 are single-sided originals. An example will be described. In this case, the user must select the following 3
The street is conceivable.

1) All originals are output by single-sided copying.

2) All originals are output as double-sided copies.

3) All originals are regarded as double-sided originals, and double-sided → double-sided copying is performed.

Therefore, the above three selections are compared with each other.

In 1), since the printouts are all on one side, the appearance is good, but the paper is wasted. Specifically, 13 × 8 = 104 sheets will be used. Further, in this case, first, the last two originals are sorted and copied from one side to one side with 8 copies, and then the three two-sided originals are sorted and copied from both sides to one side with 8 copies, and then the first copy. It is troublesome to make a sort copy of five originals from one side to eight sides.

In the case of 2), the number of prints is (3 + 3 + 1) × 8 = 56 sheets in double-sided copying, and the paper can be saved. However, as for the operation for this, first, the last two originals are sorted and copied from one side to both sides 8 copies, and then the three two-sided originals are sorted and copied from both sides to both sides 8 sides, and then the first copy. It becomes troublesome to make a sort copy of five originals from one side to eight sides. Furthermore, in this method, only the back side of the third print is unprinted and unnatural.

In the case of 3), the operation is the simplest, since only one sort copy of double-sided → 8-sided copy is performed once. However, the number of sheets of paper used is 10 × 8 = 80 sheets. Furthermore, since the back side of a single-sided original without an image is also copied, the copier wears out quickly, and the backside copy of a single-sided original without an image is unsightly to look because stains and the like are printed. In the first place, it is visually unpleasant that a single-sided original and a double-sided original are mixed.

The present invention has been made in view of the above problems, and an object of the present invention is to determine the presence / absence of an image on a document when copying a large number of documents and to eliminate unnecessary information in the document. It is an object of the present invention to provide an image forming apparatus that does not waste a sheet of paper without outputting a copy of a sheet of white paper even if it is mixed.

[0015]

In order to achieve the above-mentioned object, the present invention has a storage means for storing image data obtained by optically reading images of a plurality of originals by the reading means. In an image forming apparatus that reads out stored image data and outputs an image, a determination unit that determines the presence or absence of an image in each document of the plurality of documents, an identification unit that identifies a document with an image according to the determination, and the identification And an output unit for visually outputting the image of the original document according to a predetermined format.

[0016]

Embodiments of the present invention will be described below in detail with reference to the accompanying drawings.

FIG. 1 is a diagram showing a sectional structure of an image forming apparatus (copying apparatus) according to the present embodiment, in which 100 is shown.
Is a copying machine main body, 180 is a circulating automatic document feeder (R
DF). Further, 101 is a platen glass as a document placing table, 102 is a scanner, and the document illumination lamp 1
03, a scanning mirror 104 and the like. Here, the scanner 102 is reciprocally scanned in a predetermined direction by a motor (not shown), and the reflected light 107 from the original is scanned by the scanning mirror 10.
A lens 108 is passed through 4 to 106 to form an image on the CCD sensor 109.

Reference numeral 120 denotes an exposure control unit, which is composed of a polygon scanner (not shown) or the like, and outputs a laser 129.
Further, in the CCD sensor 109 as the image sensor unit, the reflected light 107 from the input document is converted into an electric signal, and based on this, modulated based on an image signal on which predetermined image processing described later is performed. Laser light 129
Is output from the exposure control unit 120, and the photoconductor drum 11
It is irradiated to 0.

Around the photosensitive drum 110, a primary charger 112, a developing device 121, a transfer charger 118, a cleaning device 116, and a pre-exposure lamp 114 are installed. In the image forming unit 126, the photosensitive drum 110 is
A motor (not shown) rotates in the direction shown by the arrow in the figure, and after being charged to a desired potential by the primary charger 112, the laser beam 129 from the exposure controller 120 is irradiated, resulting in a static charge. A latent image is formed. Then, the electrostatic latent image formed on the photosensitive drum 110 is developed by the developing device 121 and visualized as a toner image.

On the other hand, from the upper cassette 131 or the lower cassette 132, the pickup rollers 133, 134
The transfer paper fed by the paper feed roller 135, 136
Is sent to the main body of the copying machine by the registration roller 137 and is fed to the transfer belt. Then, the visualized toner image is transferred to transfer paper by the transfer charger 118. From the photosensitive drum 110 after this transfer, the cleaner device 1
16 removes residual toner, and the pre-exposure lamp 114
As a result, the residual charge is erased.

The transfer paper after the transfer of the toner image is separated from the transfer belt 130, the toner image is recharged by the pre-fixing chargers 139 and 140 and sent to the fixing device 141, where it is pressed and heated. It is fixed. Then, the paper is discharged to the outside of the main body 100 by the paper discharge roller 142.

Reference numeral 138 denotes an adsorption charging device for adsorbing the transfer paper sent from the registration roller 137 to the transfer belt 130, and 139 is used for rotating the transfer belt 130 and at the same time forms a pair with the adsorption charging device 138. And a transfer belt roller that attracts and charges the transfer paper to the transfer belt 130.

The copying machine main body 100 includes, for example, 4000
A deck 150 capable of storing a sheet of transfer paper is provided. The lifter 151 of the deck 150 is the paper feed roller 1
The transfer sheet rises in accordance with the amount of the transfer sheet so that the transfer sheet always contacts 52. Further, a multi-purpose manual feed 153 capable of accommodating 100 sheets of transfer paper is equipped.

Reference numeral 154 denotes a paper discharge flapper, which switches the path between the double-sided recording side or the multiple recording side and the paper discharge side. The transfer paper sent from the paper discharge roller 142 is switched to the double-sided recording side or the multiple recording side by the paper discharge flapper 154. Further, reference numeral 158 denotes a lower conveyance path, which transfers the transfer paper sent from the paper discharge roller 142 to the reverse path 1
The transfer paper is turned over via 55 and is guided to the re-feed tray 156. Further, reference numeral 157 denotes a multiple flapper that switches between double-sided recording and multiple recording paths. By tilting this flapper to the left in the figure, the transfer paper is not passed through the reverse path 155,
Directly to the lower transport path 158.

Numeral 159 is a paper feed roller for feeding the transfer paper to the photosensitive drum 126 side through the path 160. A discharge roller 161 is disposed near the paper discharge flapper 154 and discharges the transfer paper switched to the paper discharge side by the paper discharge flapper 154 to the outside of the machine. During double-sided recording (double-sided copying) or multiplex recording (multiplex copying), the discharge flapper 154 is raised and the copied transfer paper is turned upside down via the transport paths 155 and 158 and placed on the re-feed tray 156. Store. For double-sided recording, multiple flapper 1
57 is tilted rightward, and at the time of multiplex recording, the transfer sheets stored in the re-feed tray 156 are guided one by one from the bottom by the sheet feeding roller 159 to the registration roller 137 of the main body via the path 160. Get burned.

When the transfer sheet is reversed and discharged from the main body of the copying machine, the discharge flapper 154 is raised and the flapper 157 is tilted to the right to convey the copied transfer sheet to the conveying path 155 side. After the trailing edge of the transfer paper has passed the first feed roller 162, the reverse roller 163 makes a second
To the feed roller side. Then, the discharge roller 161
Causes the transfer paper to be turned over and ejected out of the machine.

FIG. 2 is a block diagram showing the arrangement of the image forming apparatus according to this embodiment. In the figure, the image reading unit 201 includes a lens 108 and a CCD sensor 10.
9. The analog signal processing unit 202 and the like. The original image formed on the CCD sensor 109 via the lens 108 is converted into an analog electric signal here. Then, the converted image information is processed by the analog signal processing unit 202.
Is input to the digital camera, where sample and hold, dark level correction, and the like are performed, and then analog-digital conversion (A / D conversion) is performed.

The thus digitized signal is input to the electronic sorter unit 203 after shading correction (variation of sensors for reading a document and correction of light distribution characteristics of a document illumination lamp) and scaling processing. .

The external I / F processing unit 209 develops image information input from an external computer (not shown) and inputs it to the electronic sorter unit 203 as image data. In the electronic sorter unit 203, correction processing required in the output system such as γ correction, smoothing processing, edge enhancement, other processing, processing, etc. are performed, and the processed signal is output to the printer unit 20.
4 is output. As shown in FIG. 1, the printer unit 204 includes an exposure control unit 120 including a laser and the like, and an image forming unit 1.
26, a transfer paper conveyance control unit, etc., and visibly records an image on the transfer paper according to the input image signal.

Further, the CPU circuit section 205 includes the CPU 20.
6, the ROM 207, the RAM 208, and the like, and controls the image reading unit 201, the electronic sorter unit 203, the printer unit 204, and the like described above to integrally control the sequence of the present apparatus.

FIG. 3 is a block diagram showing the detailed structure of the electronic sorter unit according to the present embodiment. The image sent from the image reading unit 201 of FIG. 2 is input to the electronic sorter unit shown in FIG. 2 as the brightness data of Black, and the data is input to l
It is sent to the og converter 301. This log conversion unit 301
Stores a lookup table (LUT) for converting the input luminance data into density data,
The brightness data is converted into the density data by outputting the table value corresponding to the input data.

The density data obtained by the above conversion is 2
The multivalued density data is sent to the binarization unit 302, where 2
The value is converted into a value of "0" or "255". Then, the binarized 8-bit image data is
Converted to 1-bit image data of "0" or "1". Therefore, the amount of image data stored in the memory becomes small.

However, when the image data is binarized, the gradation number of the image changes from 266 gradations to 2 gradations.
Image data having many halftones such as a photographic image is generally significantly deteriorated by binarizing the image data. So 2
It is necessary to express a pseudo halftone with the value data.

Here, the error diffusion method is used as a method of artificially expressing halftone with binary data. In this method, if the density of a certain image is larger than a certain threshold value, it is the density data of '255', and
If it is less than or equal to a certain threshold value, the density data of '0' is binarized, and then the difference between the actual density data and the binarized data is used as an error signal of the pixel of interest. This is a method of allocating to surrounding pixels.

The distribution of the error is performed by multiplying a weighting coefficient on a matrix prepared in advance with the error generated by binarization and adding it to the peripheral pixels. As a result, the average value of the densities of the entire image is saved, and the halftone can be represented in a pseudo binary manner.

The image data thus binarized is sent to the image buffer A or the image buffer B303.
Also, image data from a computer input from an external I / F processing unit (not shown) is transferred to the external I / F processing unit 2
Since it is processed as value image data, it is sent to the image buffer A or the image buffer B 303 as it is.

In the above image buffer 303, the control unit 3
In response to a command from 00, all the images of the original document to be copied are temporarily stored in the image storage unit 304, or the image data is sequentially read from the image storage unit 304 and output. The image storage unit 304 has a SCSI controller and a hard disk (memory), and writes image data in the hard disk according to a command from the SCSI controller.

The image buffer 303 is composed of a RAM capable of accommodating one page of image data, and absorbs the difference between the read image data transfer speed, the recording / reproducing speed of the SCSI controller and hard disk, and the recording speed of the printer. Play a role. Further, by alternately using the two image buffers, the image buffer A and the image buffer B, both image reading and recording on the hard disk can be performed without interruption, or both reading from the hard disk and recording on the printer can be performed. Or continuously.

That is, for example, at the time of image reading, the read image is recorded in the buffer A and at the same time the already read image in the buffer B is recorded, and at the same time, the already read previous page image in the buffer A is recorded. Record the data on the hard disk. Further, the buffer A and the buffer B are switched for each page to alternately read and transfer the data to the hard disk. Similarly, when transferring from the hard disk to the printer, the image data is transferred from the hard disk to the printer alternately by switching the buffer A and the buffer B for each page. The control unit 300 controls the flow of image data to and from the image buffer A and the image buffer B as described above, according to a command from the main body.

The plurality of image data stored in the hard disk are output in the order according to the editing mode designated by the operation unit of the copying machine. For example, in the case of sorting, the document is read from the DF in order from the last page of the document stack to the first page, and temporarily stored in the hard disk. And
From the last page to the first page, the image data of the document once stored is sequentially read from the hard disk, and this is repeated a plurality of times and output. This allows
It can play the same role as a sorter with multiple bins.

The image data retrieved from the image storage unit 304 is sent to the smoothing unit 305. In the smoothing unit 305, first, 1-bit data is converted into 8-bit data, and the image data signal is brought into a state of “0” or “255”. The converted image data is replaced with a weighted average value obtained by the sum of the coefficients on a predetermined matrix and the density values of neighboring pixels. As a result, the binary data is converted into multi-valued data according to the density value in the neighboring pixels,
Image quality closer to the scanned image can be reproduced.

Then, the smoothed image data is input to the γ correction unit 306, and when the density data is output, conversion is performed by the LUT in consideration of the characteristics of the printer, and the density set by the operation unit is set. Adjust the output according to the value.

In the electronic sorter section shown in FIG. 3, the above-mentioned configuration is a general electronic sorter configuration, but in the present embodiment, an image presence / absence determining circuit 307 is further added. The image presence / absence determining circuit 307 determines from the 8-bit signal of the input read image data whether or not there is an image in the original document, and the result is determined by the control unit 3.
Notify 00.

According to the result, the control unit 300 does not write the binary image data stored in the image buffer into the image storage unit 304 or transfer it to the printer unit when there is no image. However, only when there is an image, the binary image data is written in the image storage unit 304 or transferred to the printer unit. As a result, the image recorded on the printer is only the image of the original surface on which the image actually exists.

FIG. 4 is a flowchart showing the control procedure in the image forming apparatus according to this embodiment.

The user installs a document bundle in which one-sided and two-sided documents are mixed in a circulating automatic document feeder (RDF),
Press the start switch on the device. This makes RDF
Sets the originals on the original placing table one by one from the last page of the original bundle (step S401). There is always an image on the front of the original regardless of whether it is a single-sided original or a double-sided original.
The original is unconditionally read on the front side (step S4).
02), the image is recorded on the hard disk (step S403).

Next, the document is turned over by RDF (step S404), and the image on the back side is read (step S404).
405), the image presence / absence determination circuit 307 determines whether or not there is an image on the back surface thereof (step S40).
6). Then, only when there is an image, the image is recorded on the hard disk (step S407).

The read document is turned over again and returned to the top of the original document stack (step S40).
8). Then, it is determined whether or not there are unread originals remaining on the RDF (step S409).
The process returns to step S401 to read the next original. However, if there are no originals left, the above-described sort function prints only the number of copies, both sides or only one side. However, even when printing only on both sides, if the number of document sides with images is odd, the final print is one-sided print.

FIG. 5 is a block diagram showing the configuration of the image presence / absence determining circuit 307 of FIG. 6 and 7 show histograms for explaining the operation of the image presence / absence determination circuit 307 shown in FIG.

In FIG. 5, 8-bit read image data is input to the comparator 801. The comparator 801 has its threshold value set to a level close to white, and data having a value lower than the threshold value is detected in a portion of the document other than the blank sheet. A counter 802 counts the number of pixels output from the comparator 801 and lower than this threshold value. Then, the CPU 803 determines that there is an image when the count value of pixels on one document surface is larger than a predetermined value.

FIG. 6 shows an example of a histogram of an original having an image, and FIG. 7 shows an example of a histogram of an original having no image. The counter 802 in FIG. 5 calculates the total number of pixels on the left side of the threshold values of these histograms. Then, the CPU 803 resets the counter 802 for each original and determines the presence or absence of an image based on the obtained count value.

Here, an example of printing in the present embodiment without using the above-described image presence / absence determining circuit will be described.

FIG. 8 and FIG. 9 are display examples of the operation panel when the image presence / absence determining circuit is not used. The left square portion of the operation panel shown in FIG. 8 is a so-called touch panel. Therefore, when copying a plurality of copies of a document bundle in which a single-sided document and a double-sided document are mixed, the user first presses the document both-sides and one-sided switch 1201 on the operation panel of FIG. Then, the screens are switched and the display shown in FIG. 9 is made.

In FIG. 9, reference numeral 1301 denotes a switch for instructing whether one side of the original is double-sided. 1302 is
This is a switch for instructing the start of image reading.
Further, reference numeral 1303 denotes the number of one-sided and double-sided sheets of the document already read. 1304 is a switch for instructing whether the print is on both sides or one side.
Indicates the number of copies to be printed, and 1306 is a switch for returning the display to the display shown in FIG.

FIG. 10 is a flow chart showing the operation procedure of the operation panel shown in FIGS. In this case, it is assumed that the original stack includes five single-sided originals, three double-sided originals, and two single-sided originals in order from the first page, and eight copies of the originals are electronically sorted and output by double-sided printing. .

First, the first five one-sided originals are set in the RDF (step S1501). Then, the original single-sided switch 1301a in FIG. 9 is pressed. Here, if the one-sided switch 1301a is in the pressed state from the beginning in the default setting, it is confirmed (step S1502). Next, when the reading switch 1302 is pressed, the five single-sided originals on the RDF are read.

Upon completion of the above reading, the user
The five originals that have been read are removed, and then three double-sided originals are placed in the RDF (step S150).
4). Then, the double-sided original switch 1301b is pressed (step S1505).

Thereafter, the reading is performed in the same manner as described above, the two single-sided originals are similarly set, and the original image is read (steps S1506 to S1509). When the reading of all the originals is completed in this way, the user confirms the display of the input originals (step S1510). This display indicates that, as indicated by reference numeral 1303 in FIG. 9, five single-sided originals, three double-sided originals, and two single-sided originals have already been read.

Next, the user selects the print double-sided switch 13
Press 04b and enter the number of copies as "8". Then, when the start button 1307 is pressed after the above settings are completed, eight copies of the images of all the read originals are output by double-sided printing.

As described above, according to the present embodiment, the image of the front side of the document is unconditionally read and stored, the document is turned over and the image on the back side is read, and the image presence / absence judgment circuit is read. If there is an image on the back side, the image is stored only by storing the image on the back side. Even if a document with an image on only one side and a document with an image on both sides are mixed, only double-sided printing is possible. Output or only single-sided printing can be performed, waste of print paper can be eliminated, and operability, functionality, and copy productivity of the apparatus are improved.

The present invention is not limited to the above-mentioned embodiments, and various modifications can be made without departing from the spirit of the present invention. Hereinafter, modified examples of the above embodiment will be described. <Modification 1> FIG. 11 is a flowchart showing a modification of the control procedure in the image forming apparatus according to the above embodiment shown in FIG. Note that in FIG. 11, the same control as the control in FIG. 4 is denoted by the same reference numeral, and description thereof is omitted here. That is, steps S401 to S4
The part 10 is the same control as FIG.

The control shown in FIG. 5 differs from the control shown in FIG. 4 in that step S411 is added. In step S411 of FIG. 5, it is determined whether or not there is an image on the front surface of the document, and if it is determined that there is no image on the front surface, the process of step S403 is skipped and the image is not recorded on the hard disk.

The process shown in FIG. 5 has the following two advantages as compared with that shown in FIG. That is, (1) In the process shown in FIG. 4, the user has to set all one-sided originals face up, whereas in FIG. 5, the single-sided originals may be placed face up or face down. (2) Even if the user mistakenly mixes a blank sheet into the original bundle, the blank original portion is not automatically printed. However, if the user intentionally inserts a blank sheet,
It goes without saying that the control according to the above-described embodiment shown in FIG. 4 can obtain a print result that matches the intention of the user. <Modification 2> FIG. 12 is a modification of the electronic sorter unit according to the above embodiment shown in FIG. Here, the same components as those of the electronic sorter unit shown in FIG.
A description thereof will be omitted.

The image presence / absence determining circuit of the electronic sorter section shown in FIG. 12 determines the presence / absence of an image in the binarized image data. FIG. 13 shows a circuit configuration of the image presence / absence determining circuit 308 in the electronic sorter unit of FIG. In FIG. 13, a common data transfer clock (not shown) is supplied to the FIFOs 2001 and 2002, the flip-flops (shift registers) 2003 to 2009, and the counter 2010. This circuit sequentially fetches the binarized image data and outputs the image data as shown in FIGS.
Perform type template matching.

14 to 16, the black portion of the image is represented by "1". In this circuit, as shown in FIG. 14, when the vertical 2 pixels and the horizontal 2 pixels are all "1", or As shown in FIGS. 15 and 16, the case where three pixels in a vertical or horizontal row are “1” is detected, and the number is counted. The reason for using such a template is to distinguish noise from an image. Then, the CPU 2011 resets the counter 2010 for each side of the document. CP
U2011 determines that an image is present when the count value on one document surface is larger than a predetermined value.

The electronic sorter unit shown in FIG. 12 uses the binarized image for the determination, although the timing of issuing the determination result is slightly delayed as compared with the electronic sorter unit shown in FIG.
The presence / absence of an image can be easily determined. <Modification 3> FIG. 17 shows another modification of the electronic sorter unit according to the above embodiment shown in FIG. Again, FIG.
The same components as those of the electronic sorter unit shown in are given the same reference numerals and the description thereof will be omitted.

The image presence / absence determining circuit 308 in the electronic sorter section shown in FIG. 17 is the same as the image presence / absence determining circuit according to the second modification shown in FIG. 13 and handles binary images. The electronic sorter unit shown in FIG. 17 temporarily records all the images in the image storage unit 304 regardless of whether the document has an image or not. Then, the image presence / absence determination circuit 308 determines the presence / absence of an image in the image data read from the image recording unit 304, and sends the result to the control unit 300.

When the control unit 300 transfers the image data in the image storage unit 304 to the image buffer 303, it does not transfer the data corresponding to the image determined to have no image data. Therefore, the printer does not print a blank portion such as the back surface of a one-sided original.

As described above, the electronic sorter section shown in FIG. 17 requires a storage capacity in the image storage section 304 as compared with the electronic sorter section shown in FIGS. The processing time of the entire apparatus can be shortened as much as the image data can be captured smoothly. <Modification 4> In the device according to the above-described embodiment, one side,
The two-sided originals are separately read alternately, but if the user knows the arrangement of the one-sided originals and the two-sided originals in advance, the number and the arrangement of the two-sided originals can be displayed by the user on the display 1303 in FIG. It may be set in advance and the entire original bundle may be read at once according to the setting. FIG. 18 shows a display example of the operation panel in that case.

In FIG. 18, the user sets the entire original bundle to R
After being installed in the DF, the switch 1701 pushes either one side or both sides. As a result, a frame-shaped marker is displayed in the number display area 1702, and the number input key 1
703 is used to input the number of sheets. For example, one side of the switch 1701 is displayed as a marker, and the number display of 1702 is displayed as "5".

The user can select one
After designating both sides and the number of sheets, the print both sides switch 1304b is pressed and the number of copies is input as "8". When the above settings are completed, the start button 1307 is pressed to output eight copies of the images of all the read originals by double-sided printing.

As described above, the above embodiment shown in FIGS. 8, 9 and 10 and the modification 4 shown in FIG.
In this case, since the presence / absence of an image is manually determined without using the image presence / absence determining circuit, as compared with the case of using the image presence / absence determining circuit shown in FIGS. You can instruct it not to print any unwanted writing or stains on it.

Thus, as shown in FIG. 8, FIG. 9 and FIG.
The apparatus according to the above-described embodiment includes an image presence / absence determining circuit, like the electronic sorter unit shown in FIG. 3 and FIGS. It is also possible to use a device that selectively uses and. But,
In the case shown in FIGS. 8, 9 and 10 according to the above-described embodiment and the modified example thereof shown in FIG. 18, if only the functions shown therein are used, FIG. The image presence / absence determining circuit may be removed from the electronic sorter unit shown in FIGS. In this case, only a normal electronic sorter configuration is used without adding a special circuit, and only a two-sided document is mixed with a plurality of documents in which a document with an image on only one side and a document with images on both sides are mixed. Multiple copies of the original can be printed. <Modification 5> In the electronic sorter section shown in FIGS. 3, 12, and 13, an image buffer for temporarily storing one page or two pages of image data was provided in the preceding stage of the image storage section 304. It has a composition. Therefore, as a fifth modification, an example in which this type of image buffer is not used will be described.

FIG. 19 is a block diagram showing the structure of the electronic sorter section of the device according to the fifth modification. The electronic sorter unit shown in the figure has a configuration in which the image buffer 303 is removed as compared with the electronic sorter unit shown in FIG. 3, but by using a RAM for the image storage unit 304, the transfer speed of the read image data is increased. Also, it is synchronized with the transfer rate of image data to the printer.

Alternatively, if the image storage unit 304 is, for example,
Even if it is configured with a hard disk, in the control unit 300,
If a FIFO consisting of a small-sized RAM is provided in the input / output section of the image storage unit 304, image reading or the printer and the hard disk can be synchronized.

In the case of the electronic sorter section shown in FIG. 19, since the image buffer is not provided, the cost of the apparatus is low, but the image presence / absence determining circuit determines the presence / absence of an image when the image data is stored in the image storage section 304. It will be after being recorded in. However, this problem can be solved by the method described below.

1) Method of performing preceding image scanning The operation sequence of the apparatus in this case will be described with reference to the flow chart shown in FIG.

First, the both sides of the entire original bundle are scanned at high speed to check the number and arrangement of originals with images (step S1901). This image reading is to check the presence or absence of an image and the number of originals, not to obtain the data to be printed. Therefore, the image may be read at a speed twice or four times as high as that during normal image reading.

Next, image reading, recording of the read image data in the image storage unit, and printout of the first copy of the read image data are performed simultaneously (step S1902). Then, after that, the electronic sort function is used to output prints for the second and subsequent copies with the image data read from the image storage unit (step S19).
03).

According to this method, since high-speed preceding scanning is performed, the total processing time is shortened when there are many image-free original surfaces such as single-sided images.

2) Method of Overwriting Unnecessary Image Data Section In the electronic sorter section shown in FIG. 19, when the image presence / absence determination circuit is operated at the same time as image reading and image storage, the timing at which the image presence / absence determination circuit makes the determination is: Although the image data will be immediately after being recorded in the image storage unit 304, when it is determined that there is no image, the data to be recorded next in the image storage unit 304 is overwritten on the unnecessary image data. . As a result, the image data of the document surface without an image is not recorded in the image storage unit 304. This method is useful when the processing speed of the image presence / absence determination circuit is faster than or equivalent to the recording speed of the image storage unit 304.

3) A method of storing image data on all sides and printing out only data with images.
4 and then prints out only the image data of the original surface having the image according to the determination result of the image presence / absence determination circuit 307. This method is based on the above 1),
Although the storage capacity of the image storage unit is required more than in 2), it is useful when the recording speed of the image storage unit 304 is faster than the processing speed of the image presence / absence determination circuit.

The electronic sorter unit according to the present modification shown in FIG. 19 is less expensive than the electronic sorter unit using the image buffer because the image buffer is not used.
Further, when a RAM is used in the image storage unit 304 in FIG. 19, the cost is higher than that in FIGS. 3, 12, and 17, but the image buffer does not go through in image transfer,
Processing time can be reduced.

It should be noted that, in the above-described embodiment and its modifications, similar processing can be performed on binary image data input from an external device such as a facsimile machine or a personal computer through a communication circuit. It is possible to prevent the output of blank print.

Even when the present invention is applied to a system composed of a plurality of devices (eg, host computer, interface device, reader, printer, etc.), a device composed of one device (eg, copying machine, facsimile device) Etc.)

Another object of the present invention is to supply a storage medium having a program code of software for realizing the functions of the above-described embodiments to a system or apparatus, and to supply a computer (or CP of the system or apparatus) of the system or apparatus.
It is needless to say that it is also achieved by (U or MPU) reading and executing the program code stored in the storage medium.

In this case, the program code itself read from the storage medium realizes the function of the above-described embodiment, and the storage medium storing the program code constitutes the present invention.

As a storage medium for supplying the program code, for example, a floppy disk, hard disk, optical disk, magneto-optical disk, CD-ROM, CD
-R, magnetic tape, non-volatile memory card, ROM, etc. can be used.

Further, by executing the program code read by the computer, not only the functions of the above-described embodiments are realized, but also the OS (operating system) running on the computer based on the instruction of the program code. It goes without saying that this also includes the case where the above) performs a part or all of the actual processing and the processing realizes the functions of the above-described embodiments.

Further, after the program code read from the storage medium is written in the memory provided in the function expansion board inserted into the computer or the function expansion unit connected to the computer, based on the instruction of the program code. , The CPU provided in the function expansion board or the function expansion unit performs some or all of the actual processing,
It goes without saying that the processing may realize the functions of the above-described embodiments.

[0091]

As described above, according to the present invention,
By determining the presence or absence of images in multiple originals, and even if the originals with images on only one side and the originals with images on both sides are mixed, by performing single-sided printing or double-sided print output based on the determination result, The waste of printing paper can be eliminated, and the operability, functionality, and copy productivity of the device are improved.

According to another aspect of the invention, the image data of the back side of the original having an image on only one side is not stored in the storage means, so that the capacity of the image memory of the apparatus can be saved.

[0093]

[Brief description of drawings]

FIG. 1 is an image forming apparatus (copying apparatus) according to the present embodiment.
It is a figure which shows the cross-sectional structure of.

FIG. 2 is a block diagram showing the configuration of the image forming apparatus according to the present embodiment.

FIG. 3 is a block diagram showing a detailed configuration of an electronic sorter unit according to the present embodiment.

FIG. 4 is a flowchart showing a control procedure in the image forming apparatus according to the present embodiment.

5 is a block diagram showing a configuration of an image presence / absence determination circuit in FIG.

FIG. 6 is a diagram showing a histogram of a document having an image.

FIG. 7 is a diagram showing a histogram of an original without an image.

FIG. 8 is a diagram showing a display example of the operation panel when the image presence / absence determination circuit is not used.

FIG. 9 is a diagram showing a display example of the operation panel when the image presence / absence determination circuit is not used.

10 is a flowchart showing an operation procedure of the operation panel shown in FIGS. 8 and 9. FIG.

FIG. 11 is a flowchart showing a modified example of the control procedure in the image forming apparatus according to the present embodiment.

FIG. 12 is a block diagram according to a modification of the electronic sorter unit according to the present embodiment.

13 is a diagram showing a circuit configuration of an image presence / absence determination circuit in the electronic sorter unit of FIG.

FIG. 14 is a diagram showing an example of template matching.

FIG. 15 is a diagram showing an example of template matching.

FIG. 16 is a diagram showing an example of template matching.

FIG. 17 is a block diagram showing a configuration of another modification of the electronic sorter unit according to the present embodiment.

FIG. 18 is a diagram showing a display example of the operation panel when the entire original bundle is read at once according to the setting of the user.

FIG. 19 is a block diagram showing a configuration of an electronic sorter unit of an apparatus according to modification 5.

FIG. 20 is a flowchart showing an operation sequence in an electronic sorter unit of a device according to modification 5.

[Explanation of symbols]

 201 image reading unit 202 analog signal processing unit 203 electronic sorter unit 204 printer unit 205 CPU circuit unit 209 external I / F processing unit 300 control unit 301 log conversion unit 302 binarization unit 303 image buffers A and B 304 image storage unit 305 Smoothing unit 306 γ correction unit

Claims (8)

[Claims] 1. An image forming apparatus having a storage unit for storing image data obtained by optically reading images of a plurality of originals by a reading unit, and reading the stored image data to output an image, Determination means for determining the presence or absence of an image in each original of the plurality of originals; identification means for identifying an original having an image according to the determination; and output means for visually outputting the image of the identified original in a predetermined format. An image forming apparatus comprising: 2. The plurality of originals are originals in which an original having an image on only one side of the original and an original having an image on both sides of the original are mixed, and the identifying means sets an image on only one side of the original. The image forming apparatus according to claim 1, wherein an original and an original having images on both sides are identified. 3. The reading means unconditionally reads the images on the front surface of the plurality of originals, and the determining means determines the presence or absence of the images on the back surfaces of the plurality of originals. The image forming apparatus according to item 1. 4. The image forming apparatus according to claim 3, wherein the storage unit does not store the image data of the back side of the document having the image on only one side according to the determination. 5. The storage means stores image data in which the reading means unconditionally reads images on the front surface and the back surface of the plurality of documents, and the determining means stores the image data based on the stored image data. The image forming apparatus according to claim 1, wherein the presence or absence of an image in each of the plurality of originals is determined. 6. The determination means determines whether or not there is an image of a document in which a document having an image on only one side and a document having an image on both sides are previously separated from the plurality of documents. The image forming apparatus according to claim 1. 7. The predetermined format is output only for double-sided printing, output only for single-sided printing, or a mixture of double-sided printing and single-sided printing.
An image forming apparatus according to claim 1. 8. The method according to claim 1, wherein the determination unit determines the presence or absence of an image in each of the plurality of originals based on a histogram of white levels of the images of the plurality of originals. The image forming apparatus according to claim 7.