JP3342259B2 - Image processing device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an image processing apparatus for correcting image data obtained by reading an original image in accordance with the original image density.

[0002]

2. Description of the Related Art There is known an image processing apparatus which photoelectrically reads a document image using a CCD line sensor or the like and records or transmits image data based on the image data obtained thereby.

In this type of apparatus, in order to record an image with an appropriate density, a density correction process for correcting read image data in accordance with the density of a document image is used.

In such density correction processing, a speed-priority correction mode in which the original image density is determined in parallel with the reading of the original image to correct the image data, and the original image density is determined prior to the reading of the original image. There is a correction mode in which image data is prioritized for correcting image data.

[0005]

There are two methods of reading a document image: a method of reading a document image fixedly placed on a document table, and a method of reading a document image being transported by a transport mechanism. , Whether the manuscript is a sheet or book
Alternatively, the selection is made according to whether high-speed reading is required or whether the same document image needs to be read a plurality of times.

However, these original image reading methods and the above-described image data correction modes are incompatible with each other, and conversely, in order for them to be executed as an optimal combination, the function setting by the operator must be performed. troublesome.

[0007]

SUMMARY OF THE INVENTION The present invention has been made in view of the above points, and has as its object to enable optimal control of an image density correction mode and an original reading method. Reading means for reading the original image placed on the table and the original image being transported by the transport mechanism; and determining the image density of the original image in parallel with the reading of the original image by the reading means, and reading the image data from the reading means. Correction means operating in a first correction mode for correction and a second correction mode for determining image density of a document and correcting image data from the reading means prior to reading of the document image by the reading means; and the first correction mode Selecting means for selecting one of the second correction mode and the second correction mode; and selecting the correction mode selected by the selection means and the original image read by the reading means, Have a control means for controlling the correction mode of positive means, the control means, prior to the said selection means
The second correction mode is selected and transported by the reading unit.
If the original image being transported is read by the mechanism,
The correction mode of the correction means is the first correction mode.
And an image processing apparatus characterized by the following. Ma
Or by the original image placed on the platen and the transport mechanism.
Reading means for reading a document image being transported, and said reading means
Determines the original image density while reading the original image
A first correction mode for correcting the image data from the reading means.
Prior to reading the original image by the
The original image density is determined, and the image data from the reading means is determined.
Correcting means operating in a second correction mode for correcting;
One of the first correction mode and the second correction mode
Selecting means for selecting one of the
Correction mode and the original image read by the reading means.
Control for controlling a correction mode of the correction means according to an image
Means, and the control means controls the reading by the reading means.
If the original image placed on the platen is scanned,
The correction means in the correction mode selected by the selection means.
To provide an image processing apparatus characterized by operating
Things . Or an original image placed on the platen
Reading means for reading a document image being transported by a transport mechanism
In parallel with the reading of the original image by the reading means.
The image data density is determined and the image data from the reading means is supplemented.
The first correction mode and the reading preparative means for positive original image
Prior to reading, the original image density is determined and the
Operates in a second correction mode for correcting the image data.
Correction means, the first correction mode and the second correction mode
Selecting means for selecting any one of the above,
The correction mode selected by the step and the reading means
The correction mode of the correction means is adjusted according to the document image to be read.
Control means for controlling the operation mode, wherein the control means
The second correction mode is selected by the selection means, and the reading is performed.
The original image being transported is read by the transport mechanism
The correction of the image data by the correction means.
Providing an image processing apparatus characterized by not performing
It is.

[0008]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described below with reference to preferred embodiments.

FIG. 1 shows the configuration of a digital copying machine to which the present invention is applied, and will be described below with reference to the drawings.

The exposure lamp 201 is composed of a fluorescent lamp, a halogen lamp, or the like, and irradiates an original on an original mounting glass (original table) 200 while moving in a direction perpendicular to the longitudinal direction. The scattered light from the original due to the irradiation of the exposure lamp 201 is reflected by first, second, and third mirrors 202, 204, and 20.
5 and reaches the lens 207. At this time, the second movable body 206 composed of the second mirror 204 and the third mirror 205 moves with respect to the movement of the first movable body 203 composed of the exposure lamp 201 and the first mirror 202. ,
The distance from the original surface, which moves at half the speed and is irradiated, to the lens 207 is always kept constant. An image on the original is formed on a light receiving portion of a CCD line sensor 208 in which thousands of light receiving elements are arranged in a line via mirrors 202, 204, 205 and a lens 207, and the CCD line sensor 208 sequentially generates an image. Photoelectric conversion is performed in line units. The photoelectrically converted signal is processed by a signal processing unit (not shown), PWM-modulated, and output.

The exposure controller 210 drives a semiconductor laser based on the PWM-modulated image signal output from the signal processor, and irradiates a light beam onto the surface of the photoconductor 240 rotating at a constant speed. At this time, the light beam is deflected and scanned using a polygon mirror in parallel with the axial direction of the drum-shaped photoconductor 240. The exposure control unit 210 is cooled by the cooling fan 209.

Before irradiating the light beam with the light beam, the remaining charge on the drum is removed by a pre-exposure lamp (not shown), and the surface of the photosensitive member 240 is uniformly charged by the primary charger 228. . Therefore, the photosensitive member 240 receives the light beam while rotating, so that an electrostatic latent image is formed on the drum surface. Then, the electrostatic latent image on the drum surface is visualized with a developing material (toner) of a predetermined color by the developing device 211.

On the other hand, reference numerals 223 and 224 denote transfer paper loading sections, on which transfer paper of a fixed size is loaded and stored.

The lift-ups 225 and 226 operate to lift the transfer paper stored in the transfer paper stacking portions 223 and 224 to the position of the pair of feed rollers 229 and 232. The feed roller pairs 229 and 232 are driven by the same motor (not shown), and selectively feed the transfer paper from one of the transfer paper stacking units 223 or 224 by switching the roller rotation direction. Each pair of feed roller pairs 229 and 232 is torqued in the direction opposite to the direction of paper feeding, thereby preventing double feeding of the recording medium.

Feed rollers 230, 233, 234, 2
35 feeds the transfer paper from the transfer paper stacking units 223 and 224 to the registration roller 238. In the present embodiment, the third and fourth transfer paper stacking sections can be further connected downward to expand the transfer paper stack, and 231 transfers the transfer paper from the transfer paper stacking section connected below. This is a pair of feeding rollers that perform a sheet feeding operation leading to a feeding roller. When the manual paper feed mode is selected on the operation unit, the manual
When the transfer paper is manually fed by opening 7, the feed roller 236 feeds the manually fed transfer paper to the registration roller 238.

The registration roller 238 is provided with a photoconductor 240.
The paper to be transferred is fed to the transfer position by adjusting the timing of the leading edge of the image formed on the paper and the leading edge of the paper to be transferred. A transfer charger 239 transfers the developed toner image on the photoconductor 240 to the fed paper. After transfer, photoconductor 240
The remaining toner is removed by the cleaner 227. The transfer target paper after the transfer is easily separated from the photoconductor 240 because the curvature of the photoconductor 240 is large.
The adsorbing force between the paper and the receiving paper is weakened to facilitate separation.

The separated transfer paper is fed to a conveyor belt 241.
Are sent to the fixing units 212 and 213 to fix the toner. 212 is a ceramic heater and a film, 2
Composed of two rollers, the heat of the ceramic heater is efficiently transmitted through a thin film. The cooling roller 214 radiates heat from the fixing unit roller 213. The feed roller 215 is configured by one large roller and two small rollers, and feeds the paper to be transferred from the fixing unit.
Correct the curl of the paper to be transferred.

The direction flapper 222 switches the transfer direction of the transfer sheet according to the operation mode. In a mode in which a single transfer is performed on one side of the transfer target paper (during single-sided recording), a path from the feed roller 215 to the discharge port is selected. A discharge roller pair 216 stacks and discharges the transfer-receiving sheet on which the image formation has been completed on the discharge tray 242.

At the time of double-sided recording, the discharge roller pair 216 is rotated in the reverse direction while the rear end of the transfer-receiving sheet is left during the discharge operation by the discharge roller pair 216 after the development on one side. At the same time, the direction of the directional flapper 222 is switched so as to pass below the directional flapper 222, and the paper to be transferred is sent to the feed roller 217 from the paper discharge port. The feed roller 217 has the same configuration as the feed roller 215,
The curl of the transfer paper is corrected, and the transfer paper is placed in the intermediate tray 24.
Send to 3. Thereafter, the transfer paper is fed from the intermediate tray 243 to the feed rollers 218, 219, 221 and 235 in this order.
The paper is fed to the above-described transfer position, the toner is transferred to the back surface of the transfer-receiving paper, and further discharged to the discharge tray 242.

During multiple recording, the feed roller 215 is used.
Is passed through the right side of the direction flapper 222 in the drawing and is sent to the feed roller 217 by switching the direction of the direction flapper 222. The feed roller 217 sends the transfer sheet to the intermediate tray 243. Thereafter, the transfer paper is fed from the intermediate tray 243 to the feeding roller 2.
18, 219, 221 and 235, the paper is fed to the above-described transfer position, the toner is transferred to the same surface as the previous transfer, and further discharged to the paper discharge tray 242.

At the time of double-sided recording or multiple recording,
When recording a plurality of sheets, the first transfer sheet is fixed by the stopped feeding roller 218 and the intermediate tray 24 is fixed.
3 is loaded. When the second transfer paper arrives, the feed roller 218 starts rotating and sandwiches the two transfer papers between the rollers. The two transfer sheets are stacked on the intermediate tray 243 while being fixed by the stopped feeding roller 218. The third and subsequent transfer sheets are similarly stacked on the intermediate tray 243. At this time, the leading ends of the transfer sheets stacked later are shifted backward in the feeding direction and stacked.

When the desired number of sheets is stacked on the intermediate tray 243, the feeding operation from the intermediate tray 243 starts. The feed rollers 218 and 219 are
During the transfer of the transfer sheet to the transfer sheet 21, the separation lever 220 moves down between the leading ends of the first and second transfer sheets, and the first transfer sheet is sent to the feed roller 221 as it is. The paper is fed by the feed roller 235 and guided to the transfer position to perform the transfer. Further, the second and subsequent sheets are transferred to the separation lever 2.
20 and then feed rollers 218, 219
Is rotated backward and returned to the intermediate tray 243. The same operation is repeated to feed all the sheets to be transferred from the intermediate tray 243.

A paper detection sensor is disposed on the transfer path of the paper to be transferred, and is used for detecting an error such as a paper jam and measuring the operation timing of each unit. The first sensor 250 is located before the feed roller 235, the second sensor 251 is located before the registration roller 238, the third sensor 252 is located before the feed roller 215, and the fourth sensor 253 is located at the discharge side. Between the roller pair 216 and the paper exit,
The fifth sensor 254 is provided immediately after the feed roller 217,
The sixth sensor 255 is arranged before the separation lever 220.

Reference numeral 260 denotes a standard white plate for obtaining shading correction data for correcting a variation (shading distortion) in the output level of an image signal caused by uneven sensitivity of the CCD line sensor 208 and uneven light amount of the light source. It is for. CCD before scanning the original
By the line sensor 208, the standard white plate 260
Is scanned multiple times, and the white image data obtained thereby is used as shading correction data, and the original image is
The level unevenness correction (shading correction) of the image signal obtained by scanning with the D line sensor 208 is performed.

FIG. 2 shows an automatic document feeder (hereinafter referred to as AD).
The cross section of F) is shown.

The ADF has a lid-like structure that can be attached to and detached from the main body and that can be opened and closed with respect to the document table.
FIG. 3 shows a closed state, in which the ADF can operate at this time. Reference numeral 1515 denotes a platen glass (corresponding to the platen 200 in FIG. 1), and reference numeral 1516 denotes an attachment plate, which is a member belonging to the main body. A cable (not shown)
The DF and the main body are electrically connected to enable the cooperative operation with the main body.

The side regulating member 1501 is a member movable in a direction perpendicular to the document feeding direction, that is, in the front and rear directions in the drawing, and for adjusting the width and position of the document. When the operator places a document on the document stacking tray unit 1517 with the document face down, sets the side regulating member 1501, operates the copy start key 305, and starts a copy operation or the like. Is transmitted from the main body via the cable, and the document feeding operation starts.

When feeding paper, the lever 1518 pushes down the roller holder 1502 to lift the stopper 1519 upward, and feeds paper by rotating the paper feed roller 1503. Separation roller 1505 and roller holder 150
Reference numeral 4 separates and feeds the originals received from the paper feed roller 1503 one by one. Registration roller pair 1508, 1509
Sends the document received from the separation roller 1505 between the document holder 1510 and the document glass 1515. The document holding unit 1510 includes a pair of registration rollers 1508 and 150
The document fed from the document 9 is guided on a platen glass. Further, the original is appropriately pressed by a spring member (not shown) so that the original comes into close contact with the original platen glass 1515.

At this time, the first movable body 203 of the main body of the digital copying machine has moved below the position 1520 where the original comes into close contact with the platen glass 1515 and stopped. This scans the original sent by the ADF (CC
The photoelectric conversion is performed by the D line sensor 208). The discharge roller pairs 1511 and 1512 discharge the scanned document onto a discharge tray 1514.

Note that 1506, 1507, and 1513 are:
An error such as a paper jam is determined at ON / OFF timing by a lever switch for detecting a passing state of a document during a document feeding operation.

FIG. 3 shows the key arrangement of the operation unit of the digital copying machine, which will be described below with reference to the drawings.

Reference numeral 315 denotes a main power lamp, which is turned on when the power is turned on. A power switch (not shown) is disposed on a side surface of the main body, and controls power supply to the main body. Reference numeral 301 denotes a preheating key, which is used to turn ON / OFF a preheating mode.

A copy mode key 304 is used to select a copy mode from a plurality of functions. A fax mode key 303 is used to select a fax mode from a plurality of functions. An option mode key 302 is used to select an option mode from a plurality of functions when an optional device such as a printer is mounted.
Reference numerals 317 to 322 denote status display lamps.
During the copying operation, lamps 317 and 318 are used.
And 320 are ramps 321 and 3 during facsimile operation.
Reference numeral 22 denotes a state in which the option is being operated. Lamp 3
17, 319 and 321 indicate a normal operation state, and lamps 318, 320 and 322 indicate an error state. Further, the lamp 317 indicates that the image is being copied if it is blinking, and that the image memory is being used if it is lit. Lamp 319 is
Blinking indicates that a fax is being transmitted or received, while lit indicates that the image memory is being used. If the lamp 321 blinks, it indicates that data is being received, and if it is lit, it indicates that data is being transmitted. If the lamps 318, 320, and 322 blink in each mode, they indicate a paper jam, no paper, and no toner, and if lit, indicate a failure state.

A copy start key 305 is used to instruct the start of copying. 306
Is a stop key which is used to interrupt or stop copying.

A reset key 308 operates as a key for returning to the standard mode during standby. 309
Is a guide key, which is used when one wants to know each function. Reference numeral 311 denotes an interrupt key, which is used when the user wants to interrupt and copy during copying. 312
Is a numeric keypad, which is used to input numerical values. A clear key 313 is used to clear a numerical value. A user mode key 310 is used when the user changes the basic settings of the system.

Reference numeral 314 denotes twenty one-touch dial keys, which are used for one-touch dialing in facsimile transmission. Reference numeral 316 denotes a two-piece lid, which is a double lid having a shape in which each key portion of the one-touch dial key 314 is hollowed out. A sensor switch (not shown) detects a first state in which the two lids are closed, a second state in which only the first lid is open, and a third state in which the two lids are open. The operation of the key of the one-touch dial key 314 is determined by the combination of the three types of lids in the open / closed state. Therefore, in this embodiment, the same effect as when there are 20 × 3 = 60 keys is provided. Have.

Reference numeral 307 denotes a touch panel comprising a combination of a liquid crystal screen and a touch sensor. An individual setting screen is displayed for each mode, and various detailed settings are made by touching drawn keys. Is possible.

FIG. 4 is a block diagram of the image signal processing section of the digital copying machine.

Here, 1 is a fluorescent lamp (corresponding to the exposure lamp 201 in FIG. 1) for irradiating the original, and 2 is a moving mirror (mirrors 202, 2 in FIG. 1) for guiding the reflected light from the original.
03, 204), 3 is a CCD line sensor (corresponds to the CCD line sensor 208 in FIG. 1; hereinafter, referred to as CCD) for photoelectrically reflecting the reflected light from the document guided by the moving mirror 2, and 4 is a CCD 3 A CCD drive processing circuit for driving and processing the output signal of the CCD 3; 5, an A / D converter for converting an analog signal into a digital signal;
Is an image processing circuit having a CPU, a ROM, a RAM, etc., for processing digitally converted image signals and controlling the operation of each section of the digital copying machine.

Reference numeral 7 denotes an ABC circuit which outputs an analog signal corresponding to the output level of the A / D converter 5, 8 denotes a capacitor, 9 denotes a resistor for controlling a charging time constant, 10 denotes a resistor for controlling a discharging time constant, 11 is a resistor 9 or 10 and a capacitor 8
Is a switch (SW) for selectively connecting. The SW 11 selects the charging resistor 9 when the value of the digital signal 101 from the A / D converter 5 is the maximum, and selects the discharging resistor 9 when the value of the digital signal 101 is equal to or less than the maximum value.

The reference numeral 12 denotes a reference voltage V of the A / D converter 5 by switching between the output Vs of the ABC circuit 7 and the fixed voltage Vrt.
t, the control signal 1 from the image processing circuit 6
02 can be arbitrarily switched.

Reference numeral 13 denotes an openable and closable automatic document feeder (FIG. 2).
ADF1), 14 is ADF1
Reference numeral 3 denotes a document detection sensor provided at a document feed port. 1
Reference numeral 5 denotes a platen (corresponding to the platen 200 in FIG. 1).

Reference numeral 16 denotes an operation unit shown in FIG. 3, 17 denotes a scanning drive unit for moving the fluorescent lamp 1 and the mirror 2, 1
Reference numeral 8 denotes an ADF driving unit that performs document conveyance by the ADF 13.

FIG. 5 is a graph showing the output of the A / D converter 5 and the change over time of the reference voltage Vt fluctuating with the output. Va is analog data sampled and held by the CCD drive processing circuit 4 from the output data of the CCD 3 at the time of document scanning, that is, input voltage to the A / D converter 5.

First, the operation of the ABC circuit 7 will be described.

It is assumed that the SW 11 is switched to the Vs side by the control signal 102, that is, the side to enable the ABC circuit 7. The moving mirror 2 moves and scans in the sub-scanning direction when the original is on the original table 15, and when the original is set on the ADF 13, the mirror 2 is fixed and the original is moved by the ADF 13 so that the CCD 3 is moved.
The document image is projected onto the document. The CCD 3 is driven by a drive signal from the CCD drive processing circuit 4, and the image signals that have been sequentially photoelectrically converted are processed by the CCD drive processing circuit 4. Therefore, the input to the A / D converter 5 varies, for example, as indicated by Va in FIG. 5 according to the change in the density of the document. Here, the higher the voltage value, the higher the brightness (low density), and the lower the voltage value, the lower the brightness (high density). The output of the A / D converter 5 approaches the maximum value as the input voltage value increases, and approaches the minimum value as the input voltage value decreases.

In the region A, since Vs> Va, the output 101 of the A / D converter 5 becomes 101 <maximum value, and SW11
Connects the discharge resistor 9 to the capacitor 8 (discharge state).

Therefore, the voltage Vs decreases with a constant time constant, whereby the output value of the A / D converter 5 approaches the maximum value, and is improved from high density to low density. Next, since Va> Vs in the region B, the output 101 of the A / D converter 5 has the maximum value, and the SW 11 connects the charging resistor 9 to the capacitor 8 (charging state).

In the next area C, Va ≒ Vs is stabilized, and SW
Numeral 11 repeats charging and discharging little by little. The output 101 of the A / D converter 5 is substantially the maximum value (charge / discharge state).

In the region D, Vs> Va again holds, so the discharge resistor 10 is selected, and the output 101 of the A / D converter 5 is selected.
Is reduced to a substantially maximum value and becomes stable (discharge state).

In this way, by controlling the reference voltage Vt of the A / D converter 5 to increase or decrease, it is possible to improve the background fog of the image in real time while determining the image density in parallel with the reading of the original image. This is a function of the ABC circuit 7.

FIG. 6 shows an AE mode selection screen on the operation unit. Reference numeral 401 denotes a display screen of the touch panel sensor 307 in FIG. As described above, the touch panel sensor 30
Reference numeral 7 denotes an LCD with a touch panel having display and operation functions.
Reference numeral 402 denotes a switching switch displayed on the touch panel sensor 307. As shown in FIGS. 6A and 6B, the operator sets S
By pressing W402, the pre-scan AE and the real-time AE can be appropriately switched. Note that the switch SW corresponding to the selected AE mode is displayed dark.

Next, the AE operation will be described with reference to the flowchart of FIG.

First, the operator selects either the pre-scan AE or the real-time AE using the display screen of FIG. 6 (S301).

When the copy button 305 of the operation unit is pressed, the image processing circuit 6 causes the document detection sensor 14 to output the ADF 1
It is determined whether or not a document is present in the paper feed port of the third sheet (S3).
02). If a document is present, Vt and Vs are connected by SW12 to enable the ABC circuit 7 (S303).

Next, the scanning drive unit 17 moves the fluorescent lamp 1 and the movable mirror 2 to the reading position (S30).
4). Then, the original is fed at a constant speed on the reading position by the ADF driving unit 18, and the original image is sequentially read by the CCD 3 (S305).

Here, since the ABC circuit 7 operates as described above, the output from the A / D converter 5 becomes data whose density has been corrected.

On the other hand, the single-leaf original is placed on the original platen 1 by the operator.
5, the document detection sensor 14 of the ADF 13
Does not detect the original. At this time, if the pre-scan AE is selected using the display screen of FIG.
Switches the reference voltage Vt to the fixed voltage Vrt by SW12. That is, the ABC circuit 7 is invalidated (S306, S3
07). If the real-time AE is selected, the ABC circuit 7 is effective as it is (S303).

When the prescan AE is selected and valid, the scanning drive unit 17 moves the fluorescent lamp 1 and the movable mirror 2 to measure the density of the original on the original table 15 prior to the main scan, and the entire original is scanned. Alternatively, a part is sequentially read by the CCD 3 (S308). The image processing circuit 6 creates, for example, a density histogram based on the read original density data, and calculates an optimal density correction value based on the density histogram (S3).
09).

After that, the original is fully scanned, and
The original is again scanned by the CCD 3 to record the original image. At this time, the image processing circuit 6 corrects the output image data of the A / D converter 5 with the density correction value calculated as described above (S310).

Thereafter, post-processing (external transfer, laser driving, etc.) is performed on each output data (S311).

(Second Embodiment) FIG. 8 shows an AE of another embodiment.
It is a flowchart explaining an operation.

First, the operator selects one of the pre-scan AE and the real-time AE using the display screen of FIG. 6 (S501).

When the copy button 305 is pressed, it is first determined whether the pre-scan AE or the real-time AE (ABC) is selected (S502).

When the real-time AE is selected, Vt and Vs are connected by SW12 and the ABC circuit 7
Is enabled (S503).

Next, the scanning drive unit 17 moves the fluorescent lamp 1 and the moving mirror 2 to the reading position (S504).
After that, the ADF 13 is driven by the ADF driving unit 18, the original is fed at a constant speed on the reading position, and the original image is sequentially read by the CCD 3 (S505).

Here, since the ABC circuit 7 operates as described above, the output from the A / D converter 5 becomes data whose density has been corrected.

On the other hand, when the prescan AE is selected, the image processing circuit 6 switches the reference voltage Vt to the fixed voltage Vrt by using the switch SW12. That is, the ABC circuit is invalidated (S506).

Next, the image processing circuit 6 operates as the original detecting sensor 1.
Then, it is determined whether or not a document exists in the paper feed port of the ADF 13 (S507). When a document is present, it is impossible to perform prescan AE, so that the AE operation is prohibited, and the ADF 13 is driven by the ADF drive unit 18 to immediately scan the document, and the document is fed to the reading position. The document is scanned (S508).

On the other hand, the single-leaf original is placed on the original platen 1 by the operator.
5, the document detection sensor 14 does not detect the document. At this time, since the prescan AE can be operated properly, the fluorescent light 1 and the movable mirror 2 are moved in the sub-scanning direction by the scanning drive unit 17 to measure the density of the original, and all or a part of the original is scanned. Pre-scanning is sequentially performed by the CCD 3 (S509).

The image processing circuit 6 calculates an optimum density correction value based on the read original density data (S510). Then, in order to perform a full scan of the original, the original is again
Scan with. At this time, the image processing circuit 6 corrects the output data of the A / D converter 5 with the calculated density correction value (S511).

Post-processing (external transfer, laser drive, etc.) is performed on each of the output data (S512).

(Third Embodiment) FIG. 9 shows a system in which a facsimile function, an electronic sorter function, and a scanner function are added to the basic copy function.

In FIG. 9, the signal processing circuit 6 performs processing relating to the basic copy function, and
1. The image storage unit 602 performs processing relating to the facsimile function and the electronic sorter function on the image data from the signal processing circuit 6, respectively. Furthermore, the external connector 60
It is also possible to send the image data to the outside via the interface 3.

In the facsimile transmission operation, the image data is sent from the signal processing circuit 6 to the facsimile unit 601 and transferred to the outside as a facsimile signal via a line.

During the operation of the electronic sorter, image data is sent from the signal processing circuit 6 to the image storage unit 602, and image information of a plurality of originals is stored in a storage medium such as a magneto-optical disk built in the storage unit 602. Further, the storage unit 60
The image data is returned to the signal processing unit 6 after the processing such as image sorting in 2.

The image data can be transferred to an external device (not shown) via the connector 603 as a scanner operation.

In this embodiment, the priority use AE operation (prescan AEor) is individually performed in each of the above operation modes.
Set real-time AE).

FIG. 10 shows an AE mode selection screen on the operation unit. 501 is a display screen of the touch panel 307,
Reference numeral 502 denotes a displayed switch SW.

FIG. 10A shows an AE selection screen during a copy operation. FIG. 10B shows an AE selection screen during the FAX operation, and FIG. 10C shows an AE selection screen during the scanner / electronic sorter operation.

Using the switch 502 on the screen 501 corresponding to each of the above functions, the type of AE is selected, that is, either the image-priority pre-scan AE or the speed-priority real-time AE is selected. Each display screen has mode keys 302 and 30.
Switching can be easily performed by the operations of 3, 304.

After individually setting the AE mode as shown in FIG. 10, the AE operation is performed in the same manner as in the first and second embodiments.

(Fourth Embodiment) FIG. 11 shows a display in the fourth embodiment.

In the case where the prescan AE or the real-time AE is used or the AE is prohibited as in the first embodiment or the second embodiment, the display screen 7 is displayed.
01, displays 703, 704, and 705 that allow the operator to clearly identify.

FIG. 11A shows an AE display screen when the pre-scan AE is selected.
(2) is a used AE display screen when the real-time AE is selected. FIG. 11C shows a display screen when the use of the AE is prohibited.

It is needless to say that the present invention is not limited to this example as long as it can be clearly identified.

With the above configuration, it is possible to perform density correction in an optimal AE mode regardless of use conditions. The operator can always check the operation mode.

[0088]

As described above, according to the present invention, the selected correction mode is the first correction mode in which the original image density is determined in parallel with the reading of the original image and the image data is corrected. A second correction mode for determining the original image density and correcting the image data before reading the image,
In addition, since the image data correction mode is controlled according to whether the read original image is the original image placed on the original platen or the original image being transported by the transport mechanism, the original image density correction mode and the original The reading method can be optimized,
Efficient and good original image processing is possible.

[Brief description of the drawings]

FIG. 1 is a diagram showing a configuration of a digital copying machine to which the present invention is applied.

FIG. 2 is a diagram showing a configuration of an ADF.

FIG. 3 is a diagram illustrating an appearance of an operation unit.

FIG. 4 is a diagram showing a configuration of an image signal processing unit.

FIG. 5 illustrates an operation of an ABC circuit.

FIG. 6 is a diagram showing a display screen of an operation unit.

FIG. 7 is a flowchart illustrating a control procedure in an AE mode.

FIG. 8 is a flowchart showing another control procedure of the AE mode.

FIG. 9 is a diagram showing a system configuration.

FIG. 10 is a diagram showing a display screen of an operation unit.

FIG. 11 is a diagram showing a display screen of an operation unit.

[Explanation of symbols]

 3 CCD line sensor 6 Image processing circuit 7 ABC circuit 13 ADF 16 Operation unit

──────────────────────────────────────────────────続 き Continued on the front page (58) Field surveyed (Int.Cl. ⁷ , DB name) H04N 1/00 H04N 1/04 H04N 1/40-1/409

Claims (4)

(57) [Claims] A reading means for reading a document image placed on a document table and a document image being conveyed by a conveyance mechanism; determining the density of the document image in parallel with the reading of the document image by the reading means; Correction means operating in a first correction mode for correcting the image data from the means and a second correction mode for determining the density of the document image prior to reading the document image by the reading means and correcting the image data from the reading means; Selecting means for selecting one of the first correction mode and the second correction mode; and selecting the correction mode according to the correction mode selected by the selection means and the original image read by the reading means. It has a control means for controlling the correction mode, the control means, the second correction mode by the selection means
Is selected and transported by the transport mechanism by the reading means
When the original image is read, the correction means
An image processing apparatus , wherein a normal mode is the first correction mode . 2. An image of a document placed on a platen and conveyance of the document
Reading means for reading a document image being conveyed by a mechanism; and reading the document image in parallel with reading of the document image by the reading means.
Determining the image density and correcting the image data from the reading means;
First correction mode and reading of an original image by the reading means
The original image density before
Correction that operates in the second correction mode for correcting image data
Means, any one of the first correction mode and the second correction mode
Selecting means for selecting one of the two, the correction mode selected by the selecting means, and the reading
The correction means according to a document image read by the means
Control means for controlling the correction mode, wherein the control means is mounted on a platen by the reading means.
When the scanned original image is read,
Operating the correction means in the selected correction mode.
An image processing apparatus characterized by the above-mentioned. 3. The correction controlled by the control means.
Display means for displaying the correction mode to be executed by the means
The image processing according to claim 1 or 2, wherein
apparatus. 4. An image of a document placed on a platen and conveyance.
Reading means for reading a document image being conveyed by a mechanism; and reading the document image in parallel with reading of the document image by the reading means.
Determining the image density and correcting the image data from the reading means;
First correction mode and reading of an original image by the reading means
The original image density before
Correction that operates in the second correction mode for correcting image data
Means, any one of the first correction mode and the second correction mode
Selecting means for selecting one of the two, the correction mode selected by the selecting means, and the reading
The correction means according to a document image read by the means
And control means for controlling the correction mode, the control means, the second correction mode by the selection means
Is selected and transported by the transport mechanism by the reading means
When the original image in the middle is read,
Characterized in that the image data is not corrected
Processing equipment.