JPH0714192B2 - Document reader - Google Patents

Description

Description: TECHNICAL FIELD OF THE INVENTION The present invention relates to a document reading device used for an image information filing device and reading a document to be filed two-dimensionally.

[Technical Background of the Invention and its Problems] Conventionally, as a document reading device used in an image information file device, when reading an image of a document, the entire surface of the document is simply 2
Binarization is performed by binarization means such as binarization or dithering. As a result, the original of characters is read by the simple binarizing means, and the original such as a photograph is read by the binarizing means using the dither method or the like.

However, it was not possible to divide one document into a character portion and a photograph portion and read the document by using different binarizing means. For this reason, when a text part and a photo part are mixed in one manuscript, only one of them can be faithfully read.

[Object of the Invention] The present invention has been made in view of the above circumstances, and an object thereof is to faithfully read both a text part and a photo part in one manuscript. In addition, the first reading mode in which the designated area is simply binarized and the outside of the designated area is dithered, and the dither binarization of the designated area is performed, and the outside of the designated area is simply processed. An object of the present invention is to provide a document reading device that can arbitrarily select a second reading mode for performing binarization processing.

[Summary of the Invention] In order to achieve the above object, the present invention designates an area on a document by a first designating means, converts an image of a document designated by the area into an image signal by a converting means, and performs this conversion. A first reading mode in which the image signal to be converted is binarized by a binarizing unit at a slice level, the image signal converted by the converting unit is provided with gradation by the gradation unit, and the binarizing unit is used. And which of the second reading modes using the gradation converting means is specified by the second specifying means, and the image signal converted by the converting means is in the area specified by the first specifying means. By determining whether it is the inner side or the outer side, when the first reading mode is designated by the second designating means, the first of the image signals converted by the converting means is selected. By the designated means The binarizing means for the image signal corresponding to the original image inside the designated area, and the gradation means for the image signal corresponding to the original image outside the area, When the second reading mode is designated by the second designating means, it corresponds to the original image inside the area designated by the first designating means in the image signal converted by the converting means. The gradation means is selected for the image signal to be generated, and the binarization means is selected for the image signal corresponding to the original image outside the area.

[Embodiment of the Invention] An embodiment of the present invention will be described below with reference to the drawings.

FIG. 1 schematically shows the document reading apparatus of the present invention. That is, a document table (transparent glass) 1 supporting the document 0 is fixed to the upper surface of the main body (not shown). The document 0 placed on the document table 1 is exposed at the time of reciprocation by the optical system including the exposure lamp 2, the mirrors 3, 4, and 5 reciprocating along the lower surface of the document table 1 in the direction of arrow e. It is designed to be scanned. In this case, the mirrors 4 and 5 move at half the speed of the mirror 3 so as to maintain the optical path length. The reflected light from the original 0 by the scanning of the optical system, that is, the reflected light from the original 0 by the light irradiation of the exposure lamp 2 is reflected by the mirrors 3, 4, 5 and then passes through the lens 6 to pass through the line image sensor (CCD). ) 7, the image of the document 0 is formed on the line image sensor 7.

The line image sensor 7 converts into an electric signal corresponding to the formed image and outputs the electric signal to an A / D conversion circuit (conversion means) 9 via an amplifier 8. This A / D conversion circuit 9
The signal supplied from the line image sensor 7 via the amplifier 8 is converted into a digital signal and output to the shading correction circuit 10. This shading correction circuit 10
Shading correction is performed on the supplied digital signal and output to the simple binarization circuit (binarization means) 11 and the dither binarization circuit (gradation means) 12. The simple binarization circuit 11 compares the signal supplied from the shading correction circuit 10 at a constant slice level, and when the signal is higher than the slice level, judges "white" and outputs a "0" signal. , If the signal is below the slice level, "black" is determined and a "1" signal is output.

The dither binarization circuit 12 binarizes the signal supplied from the shading correction circuit 10 using, for example, a dither pattern, and outputs a "0" signal or a "1" signal. The output of the simple binarization circuit 11 is supplied to the serial-parallel conversion circuit 16 via the switch circuits 13 and 15. Further, the output of the dither binarization circuit 11 is passed through switch circuits 14 and 15 to a serial-parallel conversion circuit 16
Is supplied to. A white signal generating circuit 17 that always outputs a "0" signal is connected to the switch circuits 13 and 14, respectively. The signal converted into the parallel signal by the serial-parallel conversion circuit 16 is output to the control unit (not shown) of the image file device (not shown) via the interface 18.

Further, the CPU 19 as a control unit controls the whole according to the line synchronization signal (LSYNC) from the master timing circuit 20. That is, by controlling the driver 21, the pulse motor 22 that moves the optical system is driven, and by controlling the driver 23, the exposure lamp 2 is driven. Further, the CPU 19 stores the area data supplied from the area designation board 60 via the communication controller 24 in the area data storage area of the memory 25, and the area data is also designated by the area designation control circuit 26.
It is designed to output to.

The area designation control circuit 26 switches and controls the switch circuit 15 according to the line synchronization signal (LSYNC) supplied from the master timing circuit 20, the clock (CLK), and the area data supplied from the CPU 19. Is. Further, the CPU 19 controls the switching of the switch circuits 13 and 14 in accordance with the mode designated by the operator panel 27, and outputs the concentration designation signal in accordance with the concentration set by the operator panel 27 to the simple binarization circuit. 11. It outputs to the dither binarization circuit 12 and outputs the density signal to the serial-parallel conversion circuit 16.

The area designation board 60 is for setting a reading area. This area designation has four modes: photo area, character area, masking area, and trimming area. The area designation is performed with the ten-key pad 78, and up to 3 areas can be set for one format (one original). In addition, the set area specification contents can be stored in up to 10 formats.

The operator panel 27 is constructed as shown in FIG. That is, the page inversion key 31, which specifies page inversion,
Display page 32 which is turned on by the page reverse key 31 in the page reverse mode, photo density setting keys 33 and 34 for setting the read density for the photo area, and the set density (five steps) by the photo density setting keys 33 and 34 Display unit 35 that lights up, mode switching key 36 that switches and specifies the photo reading mode of photo fine, standard, and character clear, display that displays each of the photo fine, standard, and character clear modes switched by this mode switching key 36 37, 38, 39, character density setting keys 40, 41 for setting the read density for the character area, display section 42 for lighting and displaying the set density (five steps) by the photo density setting keys 40, 41, for reading characters Density (resolution), that is, a density switching key 43 for switching and designating a fine density and a standard density, and a fine density and a standard density set by the density switching key 43, respectively. Display 4 to light display
4, 45, Photo scanning, Text scanning, Mixed scanning of photo and text Scanning designation key 46, This scanning designation key
Indicators 47 and 48 for illuminating and displaying the photo mode and character mode specified by 46, original size specification keys 49 and 50 for specifying the original size, and this original size specification key
A display unit 51 that displays the document size specified by 49, 50, an automatic paper feed key 52 that selects automatic paper feed, a display 53 that lights when automatic paper feed is performed with this automatic paper feed key 52, and is available It is composed of a display 54 for displaying whether or not it is turned on, a display 55 for displaying a paper jam, and displays 56 and 57 for displaying obstacles 1 and 2, respectively. Each of the above-mentioned indicators and display units is composed of an LED.

The number of dither gradations is different for photo fine, standard, and character clear as the photo reading modes that are designated by the mode switching key 36. The number of gradations for photo fine is "64", the standard number of gradations. Is 32 and the number of gradations for clearing characters is 18. Further, the fine density which is designated by the density switching key 43 is 16 lines / mm, and the standard density is 8 lines / mm.

FIG. 3 illustrates the configuration of the area designation control circuit 26. That is, the command data supplied from the CPU 19 is the command register 100 and the counters 102, 10
3, 104, 105, 106, 107. In addition, the above CPU19
The address data supplied from the address decoder 101
Via command register 100 and counters 102-10
Supplied to 7. Further, the counters 102 to 107 are supplied to the line timing signal (LSYN) from the master timing circuit 20.
C) and clock (CLK) are supplied. The command register 100 selects and latches command data corresponding to the address supplied from the address decoder 101, and outputs the content of the latch.

The contents of this latch are simple binarization, dither binarization and photography, and a "1" signal or "0" signal is output from the output terminal a depending on the character area mode, and whether or not it corresponds to the area A. The output terminal b outputs a "1" signal or a "0" signal, and the output terminal c outputs a "1" signal or a "0" signal depending on whether it corresponds to the area B or not. The output terminal d outputs a "1" signal or a "0" signal depending on whether or not it corresponds to. As a result, the data for each bit is output from the output end a, the “1” signal is output from the output end b for a period in the vertical direction (sub scanning direction) of the area A, and the area B is output from the output end c. The signal "1" is output during the period in the vertical direction (sub-scanning direction), and the output terminal d outputs the signal "1" during the period in the vertical direction (sub-scanning direction) in the area C. .

The counters 102 to 107 set command data corresponding to the address supplied from the address decoder 101, that is, a set value, and output a "0" signal until the set content and the count content match, and when they match, It outputs a "1" signal. Further, the counters 102 to 107 are configured to count up for each supplied clock (CLK) and clear for each line synchronization signal (LSYNC). The outputs of the counters 102, 104, 106 are supplied to one input ends of AND circuits 108, 110, 112, respectively, and the other input ends of these AND circuits 108, 110, 112 are provided with the counters 103, 105, Each of the 107 outputs is provided.

The outputs of the AND circuits 108, 110, 112 are respectively supplied to one input terminals of the AND circuits 114, 115, 116, and the other input terminals of these AND circuits 114, 115, 116 are respectively provided with the command register 100. The outputs of the output terminals b, c, and d are respectively supplied. AND circuit 114, 115, 11
The output of 6 is supplied to the exclusive OR circuit (EO
R circuit) 118 is supplied to one input terminal of this EOR circuit 118
The output of the output end a of the command register 100 is supplied to the other input end of the. The output of the EOR circuit 118 is output to the switch circuit 15 as a switching signal.

FIG. 4 shows the operation section of the area designation board.
That is, the area designation board 60 is connected to the communication controller 24 via the cable 61. On the upper surface of the area designation board 60, a liquid crystal display unit 62 that displays various modes and their coordinates, a mode change key 64 that is turned on when the mode is changed, and a trimming area designation that is input when the trimming area mode is designated. Key 65, masking area designation key 66 to be entered when designating the masking area mode, character area mode (first reading mode)
Character area setting key 67 to be input when specifying, photo area specifying key 68 to be input when specifying the photo area mode (second reading mode), online key 69 for switching between online and offline, set format Area storage key 70 to be input when storing the contents of (maximum 10 formats) (coordinate data of maximum 3 areas), area read key 71 to be input when reading the stored format, and one area for one format A designation confirmation key 72 to be input when confirmation is performed on the image file device side (not shown), a designation end key 73 to be input when the area for one format is finished, and a request to display the coordinate data of the previous area. Area designation key 74 before input, next area designation key 75 to be input when requesting display of coordinate data for the next area, above liquid crystal display Area erase key 7 to be introduced at the time of clearing the coordinate data of one area worth being displayed at 62
6, correction key 77 to be input when a part of the coordinate data is corrected, numeric keypad 78 to input the coordinate data, * key 83 to be input after the coordinate data is input by the numeric keypad 78 and after the memory number is input, and the coordinate data for one area The # key 84 that is turned on after input or when requesting display of area data, the indicator 79 that lights when the power is turned on, and the indicator 8 that lights when online
The display 81 is lit when 0 is designated, and the designation confirmation display 82 is lit to indicate designation confirmation. The ten-key pad 78, the * key 83, the # key 84 and the like are the first designating means. In addition, the above character area designation key
67, the photo area designating key 68, etc. are the second designating means.

The indicators 79 to 82 are composed of LEDs.

The electric circuit of the area designation board 60 is as shown in FIG. That is, a CPU (8085) 90 that controls the entire area designation board 60, a ROM 92 that stores a control program, a RAM 92 for storing data, and a program timer 9
3, the display 79-82, a serial interface 95 for exchanging data with the communication controller 24 via the cable 61, an input key matrix selector 97, the keys 64-78, a liquid crystal display 62, and the above-mentioned parts Is constituted by a data bus 96 for connecting the. A memory backup battery is connected to the RAM 92. Also, the above CP
U90, ROM92, RAM92, program timer 93, display 79 to 8
2. The serial interface 95 is formed on the control circuit board, and has the input key matrix selector 97 and each key.
64-78 are formed on the keyboard substrate.

In the photograph area mode, as shown in FIG. 6 (a), the reading of the image within the area designated area (areas A, B, and C) is the dither binary reading, that is, the reading of the photograph portion. The reading of the image outside the specified range is a simple binary reading, that is, the reading of the character portion. In the character area mode, as shown in FIG. 2B, the reading of an image within the area designated area (areas A, B, and C) is a simple binary reading, that is, the reading of the character portion, and the area is designated. The reading of the image outside the above range becomes the dither binary reading, that is, the reading of the photograph portion. In the masking area mode, as shown in FIG. 7C, the image in the area designated by the area (areas A, B, C) is read in white, and the image outside the area designated by the area is designated. Reading is simple binary character reading or dither binary photo reading (depending on the designation of the operator panel 27). The trimming area mode is an area-designated range (areas A, B, C) as shown in FIG.
The image inside is read by simple binary character reading or the dither binary photo reading (operator panel
(Depending on the designation of 27), the image reading outside the area designated range becomes white reading.

Next, the area designating operation by the area designating board 60 will be described with reference to FIGS. 7 and 8.
That is, the scale is written on the surface, and the original is sandwiched in a transparent, envelope-shaped area scale (not shown). Then, use the area scale to read the dimensions of the area you want to specify, and then specify the coordinates (Xa, Ya) of the upper left corner of the area you want to specify.
And enter the coordinates (Xb, Yb) of the lower right corner. For example, in the photo area mode, enter "20" with the numeric keypad 78, press the * key 83, enter "20" with the numeric keypad 78, enter the * key 83, and enter "80" with the numeric keypad 78. , * Key 83 is turned on, ten keys 78 is used to turn on “115”, and * key 83 or # key 84 is turned on. As a result, the hatched area shown in FIG. 7 is designated.

Next, the operation of the above configuration will be described. First, the case of designating and storing an area will be described with reference to FIG. That is, the operator sandwiches the document on an area scale (not shown) and reads the size of the area to be designated using the area scale. Next, when the operator designates the photo area, he / she presses the photo area mode designation key 68. Then, the CPU 90 determines the photo area mode, and displays "Photo area, MO / #
1, Xa = 20, Ya = 20, Xb = 90, Yb = 90 ”are displayed. In response to this display, the operator inputs the coordinates (Xa, Ya) at the upper left end and the coordinates (Xb, Yb) at the lower right end of the designated area using the ten keys 78 and * key 83. For example, the coordinates of the point A ′ and the coordinates of the point A ″ in the area A shown in FIG. 9 are input.
Then, the CPU 90 makes the coordinates, that is, the first format (M
R'is A ', A "as the first (# 1) coordinates for 0)
Remember in AM92.

If there is another area, the operator inputs the next area designation key 75. Then, the CPU 90 determines the designation of the next area, and the LCD area 62 displays "Photo area, M0 / #
2, Xa = 70, Ya = 80, Xb = 130, Yb = 130 ”are displayed.
In response to this display, the operator inputs the coordinates (Xa, Ya) at the upper left end and the coordinates (Xb, Yb) at the lower right end of the designated area using the ten keys 78 and * key 83. For example, the coordinates of the B ′ point and the B ″ point of the area B shown in FIG. 9 are input. Then, the CPU 90 determines that coordinates, that is, the second (# 2) coordinates for the first format (M0). B ',
B ″ is stored in the RAM 92.

Further, when there is another area, the operator inputs the next area designation key 75. Then, the CPU 90 determines the designation of the next area, and the liquid crystal display 62 displays "Photo area, M0 /
# 3, Xa =, 120, Ya = 160, Xb = 160, Yb = 200 ”is displayed. In response to this display, the operator uses the numeric keypad 78 and * key 83 to specify the coordinates of the upper left corner of the area (Xa, Ya)
And enter the coordinates (Xb, Yb) of the lower right corner. For example, the 9th
The coordinates of the point C'and the coordinates of the point C "of the area C shown in the figure are input. Then, the CPU 90 sets C ', C as the coordinates, that is, the third (# 3) coordinates for the first format (M0). ″ Is stored in the RAM 92.

When storing the designated area, the operator presses the area storage key 70. Then, the CPU 90 causes the liquid crystal display 62 to display "Area Memory Memory
No? (.12.567.9) ”is displayed. At this time, only empty memory numbers in which no format data is stored are numerically displayed. In response to this display, the operator pushes the "0" key of the ten-key pad 78 and the * key 83 to select the format number to be stored. As a result, the CPU 90 causes each area (# 1, #) for the above format number (1).
2 and # 3) coordinate contents are stored.

Although the area is designated in the photograph area mode, the area may be designated for other modes (character area mode, masking area mode, trimming area mode).

Areas for other formats (M1 to M9) can be stored in the same manner as the storage of the first format (M0).

Next, reading of the format stored as described above will be described. That is, the operator presses the area read key 71. Then, the CPU 90 judges that the area is to be read out, and displays "area area memory memory memory No? (0..34 ... 8.)" On the liquid crystal display 62. At this time, only the memory number in which the format data is stored is numerically displayed. In response to this display, the operator inputs, for example, the "0" key of the ten-key pad 78 and the * key 83 to select the format to be read. With this choice,
The CPU 90 reads the contents of the first area (# 1) of the corresponding format (M0) from the RAM 92, and displays “Photo area, M0 / # 1, Xa = 20, Ya = 20, Xb = 90, on the liquid crystal display 62. Yb = 9
"0" is displayed. Then, when the operator presses the next area designation key 75, the CPU 90 judges the designation of the next area, reads the contents of the second area (# 2) of the corresponding format (M0) from the RAM 92, and the liquid crystal display section 62 "Photo area, M0 / # 2, Xa = 70, Ya = 80, Xb = 130, Yb = 13
"0" is displayed.

When the area is designated or the area is read as described above, the designation end key
Turn on 73. Then, the CPU 90 determines that the data is transferred, and the liquid crystal display 62 displays “Photo area # 1, #
2, # 3 Data Tensou Chu! Is displayed.
Further, the CPU 90 transfers the designated area, for example, area data (# 1, # 2, 3 #) for the format (M0) to the CPU 19 via the serial interface 95, the cable 61 and the communication controller 24. When this transfer is completed, the CPU 90 displays "Photo area # 1, # 2, # 3 OK to OK OK" on the liquid crystal display 62.

The CPU 19 then transfers the transferred data, that is, the format (M
Area data (# 1, # 2, # 3) for 0) is stored in the area data storage area in the memory 25. At this time, since the area data is the photo area, the PCU 19 displays the indicator in the middle of the indicator 37 of the operator panel 27 and the indicator.
38 and 47 are lit, and the keys for photo and character reading are fixed so that they cannot be switched. In this state, the document size and the like are selected and switched, and the document 0 shown in FIG. 9 is placed on the document table 1.

When a command signal to start reading a document is supplied to the CPU 19 from the external CPU (not shown) of the image filing apparatus via the interface 18, the CPU 19 causes the driver 19 to start reading.
Is controlled to move the optical system, and the driver 23 is controlled to turn on the exposure lamp 2. As a result, the light from the exposure lamp 2 is irradiated onto the original 0, and the reflected light from the original 0 is guided to the line image sensor 7 via the mirrors 3, 4, 5 and the lens 6.

Then, the line image sensor 7 converts the image formed by the guided light into a corresponding electric signal and outputs the electric signal to the A / D conversion circuit 9 via the amplifier 8. The A / D conversion circuit 9 converts the signal supplied from the line image sensor 7 via the amplifier 8 into a digital signal and outputs the digital signal to the shading correction circuit 10. The shading correction circuit 10 performs shading correction on the supplied digital signal and outputs it to the simple binarization circuit 11 and the dither binarization circuit 12. The simple binarization circuit 11 compares the signal supplied from the shading correction circuit 10 at a constant slice level, and when the signal is above the slice level,
If "white" is determined, a "0" signal is output, and if the signal is below the slice level, "black" is determined and a "1" signal is output. The dither binarization circuit 12 binarizes the signal supplied from the shading correction circuit 10 using, for example, a dither pattern, and outputs a "0" signal or a "1" signal. The output of the simple binarization circuit 11 is supplied to the switch circuit 15 via the switch circuit 13. The output of the dither binarization circuit 11 is supplied to the switch circuit 15 via the switch circuit 14.

Further, the CPU 19 matches the area data read from the area data storage area of the memory 25 and the processing timings of the simple binarization circuit 11 and the dither binarization circuit 12 in the original 0 with respect to the sub-scanning direction and the main scanning direction. The command data is output to the area designation control circuit 26. As a result, while the sub-scanning direction is "20-80", the count value "20" is set in the counter 102, the count value "90" is set in the counter 103, and "0" is output from the output end a of the command register 100.
The signal is output, and the “1” signal is output from the output end b.

Then, while the sub-scanning direction is "80 to 90", the count value "20" is set in the counter 102, the count value "90" is set in the counter 103, and the count value "70" is set in the counter 104.
Is set, the count value “130” is set in the counter 105, the output terminal a of the command register 100 outputs a “0” signal, and the output terminals b and c output a “1” signal.

Next, while the sub-scanning direction is "90 to 130", the count value "70" is set in the counter 104, the count value "130" is set in the counter 105, and the output terminal a of the command register 100 is set.
To output a "0" signal, and output terminal c to output a "1" signal. Then, while the sub-scanning direction is "130 to 160", the "0" signal is output only from the output end a of the command register 100.

Then, while the sub-scanning direction is "160-200", the counter 106
The count value “120” is set to the counter, the count value “140” is set to the counter 107, the output terminal “a” of the command register 100 outputs the “0” signal, and the output terminal d outputs the “1” signal. Then, while the sub-scanning direction is "200 to 220", the "0" signal is output only from the output end a of the command register 100.

Therefore, the sub-scanning direction is "0-20", "130-160",
And between "160-180", the EOR circuit 118 outputs a "0" signal as a switching signal. This allows the switch circuit
15 is switched to the simple binarization circuit 11 side. As a result, the output of the simple binarization circuit 11 is the switch circuit during the sub-scanning direction.
It is supplied to the serial-parallel conversion circuit 16 via 13 and 15, and is output to the image file (not shown) side via the interface 18.

Further, the main scanning direction in the sub-scanning direction "20 ~ 80" between "20 ~ 90", the main scanning direction in the sub-scanning direction "80 ~ 90" between "20 ~ 130", The sub-scanning direction is "90-1
During the main scanning direction "70-130" between 30 "and during the main scanning direction" 120-160 "between the sub-scanning directions" 160-200 ", as a switching signal from the EOR circuit 118. Output a "1" signal. As a result, the switch circuit 15 is switched to the dither binarization circuit 12 side. As a result, during the above period, the output of the dither binarization circuit 12 is supplied to the serial-parallel conversion circuit 16 via the switch circuits 14 and 15, and is output to the image file (not shown) side via the interface 18. It

As a result, as shown in FIG. 6A, the image (photograph part) in the area-designated range (areas A, B, and C) is read in dither binary, and the image outside the area-designated range is read. An image signal in which the (character portion) is read in simple binary is output.

Further, when the transfer data from the area designation board 60 to the CPU 19 is the area data for the character area, the operation is similar to the case where the area data of the photo area is supplied. In this case, when the same area designation as the above is supplied, the EOR circuit 118 outputs "1" as a switching signal while the sub-scanning direction is "0-20", "130-160", and "160-180". Output a signal. As a result, the switch circuit 15 is switched to the dither binarization circuit 12 side. As a result, during the above period, the output of the dither binarization circuit 12 is supplied to the serial-parallel conversion circuit 16 via the switch circuits 14 and 15, and is output to the image file (not shown) side via the interface 18. It

Further, the main scanning direction in the sub-scanning direction "20 ~ 80" between "20 ~ 90", the main scanning direction in the sub-scanning direction "80 ~ 90" between "20 ~ 130", The sub-scanning direction is "90-1
During the main scanning direction between "30" and "70 to 130", and during the sub scanning direction between "160 to 200" and the main scanning direction between "120 to 160", the EOR circuit 118 outputs a switching signal. Output a "0" signal. As a result, the switch circuit 15 is switched to the simple binarization circuit 11 side. As a result, during the sub-scanning direction, the output of the simple binarization circuit 11 is switched to the switch circuit 13,
Is supplied to the serial-parallel conversion circuit 16 via 15,
It is output to the image file (not shown) side via the interface 18.

As a result, an image signal as shown in FIG. 6 (b) is output.

Next, if the transfer data from the area designation board 60 to the CPU 19 is the area data for the trimming area,
The CPU 19 stores the transfer data, that is, the area data (# 1, # 2, # 3) for the format (M0) in the area data storage area in the memory 25. At this time, since the area data is the trimming area, the CPU 19 causes the display unit 37 of the operator panel 27 and the display unit in the middle of the display unit 38, 47.
Is lit, and it is possible to switch between each key for photography, text, and reading. In this state, the photograph mode, the character mode, the document size, etc. are selected and switched, and the document 0 shown in FIG. 9 is placed on the document table 1. At this time, CPU1
In the photograph mode 9, the switch circuit 13 is switched to the white signal generation circuit 17 side, and the switch circuit 14 is switched to the dither binarization circuit 12
In the character mode, the switch circuit 13 is switched to the simple binarization circuit 11 side and the switch circuit 14 is switched to the white signal generating circuit 17 side.

Therefore, in the photographic mode, when the area data as described above is supplied, the sub-scanning direction is "0-20",
Between "130-160" and "160-180", the EOR circuit 118
Outputs a "1" signal as a switching signal. As a result, the switch circuit 15 is switched to the dither binarization circuit 12 side. As a result, the dither binarization circuit is operated during the sub-scanning direction.
The output of 12 is supplied to the serial-parallel conversion circuit 16 via the switch circuits 14 and 15, and is output to the image file (not shown) side via the interface 18.

Further, the main scanning direction in the sub-scanning direction "20 ~ 80" between "20 ~ 90", the main scanning direction in the sub-scanning direction "80 ~ 90" between "20 ~ 130", The sub-scanning direction is "90-1
During the main scanning direction "70-130" between 30 "and during the main scanning direction" 120-160 "between the sub-scanning directions" 160-200 ", as a switching signal from the EOR circuit 118. Output a "0" signal. As a result, the switch circuit 15 is switched to the simple binarization circuit 11 side, that is, the white signal generation circuit 17 side. As a result, during the above period, the output of the white signal generation circuit 17 is transmitted through the switch circuits 13 and 15 to the serial-parallel conversion circuit.
It is supplied to 16 and is output to the image file (not shown) side via the interface 18.

As a result, an image signal as shown in FIG. 6 (d) is output.

Also, when the character mode is selected, the operation is the same as in the case of the photo mode.

Further, when the transfer data from the area designation board 60 to the CPU 19 is the area data for the masking area, the same operation as in the above trimming is performed and the image signal as shown in FIG. 6 (c) is output. .

As described above, the area in the original is designated, and the image inside the area and the image outside the area corresponding to the designation are simply 2
Since the binarization circuit or the dither binarization circuit performs binarization for reading, when a text part and a photo part are mixed in one original, both can be faithfully read. Also, you can specify multiple areas above,
The areas can be specified overlapping.

Although the dither is used as the binarizing means for producing the gradation in the above-mentioned embodiment, it may be another gradation producing means for producing the gradation for each dot in several steps. . Although the area is designated by the area designation board, the area data may be supplied from the external image filing device side.

[Effects of the Invention] As described in detail above, according to the present invention, when a text part and a photo part are mixed in one manuscript, both can be read faithfully and within the designated area. Binarization processing is performed, and the first reading mode in which the dither binarization processing is performed outside the designated area, and the dither 2 is performed inside the designated area.
It is possible to provide a document reading apparatus that can perform a binarization process and can arbitrarily select a second reading mode in which the outside of the designated area is binarized.

[Brief description of drawings]

The drawings show an embodiment of the present invention. FIG. 1 is a diagram schematically showing the overall configuration, FIG. 2 is a plan view showing the configuration of an operator panel, and FIG. 3 is a configuration of an area designation control circuit. FIG. 4 is a plan view showing the configuration of the area designating board, FIG. 5 is a block diagram showing the circuit configuration of the area designating board, and FIG. 6 is a diagram showing an example of an output image in each mode. FIG. 8 is a diagram showing an area designation portion, FIG. 8 is a diagram showing a display example of a liquid crystal display unit and key operations for explaining the area designation in FIG. 7, and FIG. 9 is a diagram showing an example of area designation. . 0 ... manuscript, 1 ... manuscript table, 8 ... line image sensor, 11 ... simple binarization circuit, 12 ... dither binarization circuit,
13, 14, 15 …… Switch circuit, 17 …… White signal generation circuit,
19 …… CPU, 24 …… communication controller, 25 …… memory, 2
6 …… Area designation control circuit, 27 …… Operator panel, 6
0 …… Area designation board, 100 …… Command register, 10
1 ... Address decoder, 102-107 ... Counter, 118 ...
… EOR circuit.

Claims (1)

[Claims] 1. A first designating means for designating an area on a document, a conversion means for converting an image of a document area-designated by the first designating means into an image signal, and the conversion means. Binarization means for binarizing the image signal at the slice level, gradation means for imparting gradation to the image signal converted by the conversion means, the binarization means and the gradation means are selected. Which has a first reading mode and a second reading mode used specifically, and a second designating means for designating one of the reading modes, and an image signal converted by the converting means by the first designating means. By determining whether it is inside or outside the designated area, when the first reading mode is designated by the second designating means, the image signal converted by the converting means is detected. Out of which With selecting the binarizing means the image signal corresponding to the inside of the original image of the designated area by the first designating means,
When the gradation means is selected for the image signal corresponding to the original image outside the area and the second reading mode is designated by the second designating means, it is converted by the converting means. Among the image signals, the gradation means is selected for the image signal corresponding to the original image inside the area designated by the first designating means, and the image signal corresponding to the original image outside the area is selected. On the other hand, a document reading apparatus comprising: a selection unit that selects the binarization unit.