JPH1141454A - Control method for image reader and its recording medium - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a control method for an image reader which sets an image reading area according to the area that an original has, wherein the image reader is connected to a host device and provides read image information of the original to the host device. SOLUTION: At the time of start of reading an image, a multi-valued data monitor provided for the output of a CCD 3 for the image reader is continuously used to monitor image data when an original 1 is read, thereby finding out a border where the original 1 is present. The image reader, when transferring image data to the host device, transfers only the image data of the area 19 where the original 1 is present and informs the host device of the presence area 1a of the original 1 set by using the multi-valued data monitor; and the host device provides an image of only the area 1a where the original 1 is present.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a technique for optimizing the amount of image data by setting an image cutout area according to an area of a target document in an image reading apparatus for providing image data to a host apparatus. Things.

[0002]

2. Description of the Related Art Here, the definitions of the following terms according to the present invention will be described to clarify the contained concept.

[0003] The main scanning direction refers to a reading scanning direction in the main direction. Therefore, image data obtained by one main scan is linear one-dimensional image data, and forms one scanning line. For example, in the case of an image reading apparatus using a linear light source lamp, it can be said that one main scan is performed by one irradiation by the linear light source lamp. Also, it usually coincides with the width direction of the original to be read.

[0004] The sub-scanning direction is a scanning direction perpendicular to the main scanning direction, and linear one-dimensional image data obtained by scanning in the main scanning direction is obtained in the sub-scanning direction. The two-dimensional planar image data is accumulated by scanning. Also, it usually coincides with the length direction of the original to be read.

The multi-value data monitor is a circuit portion having a function of monitoring a plurality of pixels collectively for each scanning line on the basis of a CCD output value. Usually, a white reference is used in gain adjustment before an image reading operation. It is used to monitor the read output value of the CCD and detect variations in individual light receiving elements. However, the multi-value data monitor can monitor an output value at an arbitrary position within the effective pixels of the CCD even during a normal reading operation.

Referring to FIGS. 1, 3 and 9 to 13, image reading performed by a conventional image reading apparatus will be described.

FIG. 3 shows an outline of image reading by the image reading apparatus. FIG. 3A shows the principle of a reading operation performed by an original-mounting type image reading apparatus.

The original 1 is placed on an original placing glass 11 made of a transparent material, and is sandwiched and fixed by a backing 2. The optical system 10 reads the original illuminated through the original placing glass 11 and reads image data in the main scanning direction.
The optical system 10 is sequentially moved to read image data in the sub-scanning direction.

When reading the original 1, the optical system 10 first reads the white reference 14, corrects the dispersion of the output of the CCD built in the optical system 10 and calibrates it, and then reads the white standard 14. To start reading the original 1.

FIG. 3B shows the principle of a reading operation performed by an original reading type image reading apparatus.

An optical system 1 is provided together with an instruction to start image reading.
Numeral 0 reads the white reference 14 provided at the opposite position, corrects the dispersion of the output of the CCD built in the optical system 10 and calibrates the original. When the leading end of the document 1 is detected, the optical system 10 starts reading the document 1.

FIG. 1 shows an outline of an image reading area by the image reading apparatus. FIG. 1A shows a cross section in the main scanning direction of a reading device of a document placement type as a typical example of an image reading mechanism.

The CCD 3 reads the original 1 and the backing surface 2a of the backing 2 for fixing the original 1 as image data.

As shown in FIG. 1B, the original area 1a has a width Xb and a length Yb, but the effective reading area of the image reading apparatus has a width Xa and a length Ya. The image data read by the image reading device is constituted by data obtained by reading the document 1 and the backing surface 2a.

Referring to FIGS. 9, 11 and 12, an explanation will be given on the image reading by the image reading apparatus of the original placing type.

As shown in the block diagram of FIG. 9, one-dimensional image data in the main scanning direction, which is the output of the CCD section B51 provided in the image reading device B50, passes through an amplifier circuit B52 to an arithmetic control section B54, and further to an auxiliary control section B54. The data is accumulated by reading in the scanning direction, and is transferred to the host device B41 as two-dimensional image data.

Operation control unit B built in host device B41
42, a driver program B45 previously fetched from the memory unit B44 and the image reading device B50
In preparation for receiving image data to be transferred. The driver program B45 is provided from the image reading device B50 and stored in the memory B44 when the image reading device B50 is defined as a peripheral device connected to the host device B41.

The image data transferred from the image reading device B50 is displayed on a monitor B43, and the image data processed by the arithmetic control unit B42 is stored in an image buffer B47 of a RAM unit B46. You.

The flow of image reading will be described with reference to FIG. When an instruction to read an image is given, in the image reading device B50, in step S51, the CCD section B51 reads the white reference, and notifies the output to the multi-value data monitor B53 via the amplifier circuit B52.

In step S52, the multi-value data monitor B5
In step 3, the arithmetic control unit B54 calculates an individual variation adjustment amount based on the output data juxtaposed as the output of one scanning line, sets the parameters of the amplifier circuit B52, and adjusts the gain of the CCD unit B51.

In step S53, the original is read, and the flow advances to step S54 to transfer the image data to the host device B41.

The host device B41 receives the image data in step S55, and proceeds to step S56 to monitor B4.
3 and further proceeds to step S57 to edit the image by the application program B45a drawn from the memory unit B44 to delete the image area other than the original area, and to store the image buffer B provided in the RAM unit B46.
47.

Another flow of image reading will be described with reference to FIG. When an instruction to read an image is given, the image reading device B50 switches the CCD unit B5 in step S61.
1 reads a white reference and outputs the output to an amplifier circuit B52.
To the multi-value data monitor B53 via

In step S62, the multi-value data monitor B5
In step 3, the arithmetic control unit B54 calculates an individual variation adjustment amount based on the output data juxtaposed as the output of one scanning line, sets the parameters of the amplifier circuit B52, and adjusts the gain of the CCD unit B51.

In step S63, the original is read in the pre-read mode, and the flow advances to step S64 to transfer the image data to the host device B41.

The host device B41 receives the image data at step S65, and proceeds to step S66 to monitor the monitor B4.
An image for editing is displayed in 3 and a necessary image portion is designated to cut out an image area.

In the image reading device B50, step S
The original is read again in the pre-reading mode based on the image area specified by the cutout in 67, and the flow advances to step S68 to transfer the image data to the host device B41.

The host device B41 receives the image data at step S69, and proceeds to step S70 to monitor the monitor B4.
An image for editing is displayed on 3 and an image area is confirmed.

If there is no problem in the image area in step S71, the image reading device B50 proceeds to step S72 to read the original, and transfers the image data to the host device B41 in step S73.

The host device B41 receives the image data at step S74, and proceeds to step S75 to monitor the monitor B4.
3 and the image data is stored in the image buffer B47.

If there is a problem in the image area in step S71, the flow returns to step S66, where the image area is cut out again, and the image reading in the pre-reading mode is repeated until the image area matches the operator's request.

Referring to FIGS. 10 and 13, image reading by the image reading apparatus of the original transport type will be described.

As shown in the block diagram of FIG. 10, the one-dimensional image data in the main scanning direction, which is the output of the CCD section B51 provided in the image reading device B60, is transferred to the arithmetic control section B54 via the amplifier circuit B52, The data is accumulated by reading in the scanning direction, and is transferred to the host device B41 as two-dimensional image data.

The original conveying section B59 conveys the original to be read, and when a sensor B58 provided near the reading point detects the leading end of the original, starts reading by the CCD section B51 after a predetermined time. When the sensor B58 detects the trailing edge of the document, the reading by the CCD unit B51 ends after a predetermined time.

Operation control unit B built in host device B41
42, a driver program B45 previously fetched from the memory unit B44 and the image reading device B60
In preparation for receiving image data to be transferred. The driver program B45 is provided from the image reading device B60 and stored in the memory unit B44 when defining the image reading device B60 as a peripheral device connected to the host device B41.

The image data transferred from the image reading device B60 is displayed on a monitor B43, and the image data processed by the arithmetic control unit B42 is stored in an image buffer B47 of a RAM unit B46. You.

The flow of image reading will be described with reference to FIG. When an instruction to read an image is given, in the image reading device B50, in step S81, the CCD unit B51 reads the white reference, and notifies the output to the multi-value data monitor B53 via the amplifier circuit B52.

In step S82, the multi-value data monitor B5
In step 3, the arithmetic control unit B54 calculates an individual variation adjustment amount based on the output data juxtaposed as the output of one scanning line, sets the parameters of the amplifier circuit B52, and adjusts the gain of the CCD unit B51.

In step S83, the document transport section B59 starts transporting the document. When the sensor B58 detects the leading edge of the document in step S84, the flow advances to step S85 to start reading after a predetermined time.

When the sensor B58 detects the trailing edge of the original in step S86, the flow advances to step S87 to finish reading the original, and the read image data is transferred to the host device B41 in step S88.

The host device B41 receives the image data in step S89 and displays it on the monitor B43.
The process proceeds to step 90, where the image is displayed on the monitor B43, and further proceeds to step S91, where the image is edited by the application program B45a drawn from the memory unit B44 to delete the image area other than the document area, and the image provided in the RAM unit B46. The data is stored in the buffer B47.

[0042]

As described above, the conventional method for controlling an image reading apparatus has the following problems.

1) The image data read by the image reading device is constituted by image data of the entire effective reading area, and includes image data other than the document.

Accordingly, in the image reading apparatus, since the image data to be handled is always constituted by the image data of the entire effective reading area, the reading always requires the maximum set reading time, and further, the reading operation always requires the entire effective reading area. A memory for storing image data is required.

Further, in the host device, a necessary application program other than the driver program for the image reading device is separately activated and editing is performed, so that the operation becomes complicated, and further, the image data transferred from the image reading device becomes complicated. In addition, a memory area for edited image data is required.

2) As a measure for simplifying the operation and reducing the required memory capacity, a method of editing image data read by pre-reading has been devised. Must be repeated.

Therefore, in the image reading apparatus, at least in the first pre-reading, the image data to be handled is always constituted by the image data of the entire effective reading area, so that the capacity of the memory for storing the read image data is largely different. There is no.

In the host device, it is not necessary to separately start an application program. However, since an operation for repeating pre-reading is added, it is hard to say that the operation is complicated.

[0049]

In order to solve the above problems, the present invention employs the following means.

1) The image data is monitored in parallel with the scanning of the original by utilizing the multi-value data monitor used for adjusting the output level of the individual CCD at the start of the image reading. Detect the edge.

By taking this means, the image reading apparatus has an effect of identifying an area existing in the width direction of the document.

2) The image data is monitored by the multi-value data monitor in parallel with the original reading scan, and the end of the original in the longitudinal direction is detected.

By taking this means, the image reading apparatus has an effect of identifying an area existing in the length direction of the document.

3) In particular, in a document feed type image reading apparatus, a sensor for detecting the front end of a document is provided with a detection width in the horizontal direction, and the width of the document is detected together with the detection of the front end of the document.

By taking this means, the image reading apparatus has an effect of identifying a region existing in the width direction and the length direction of the document.

4) When the image data obtained by reading the document is transferred from the image reading device to the host device, data indicating the document area is transferred together with the image data.

By taking this means, the host device has the effect of receiving image data consisting only of the document area.

[0058]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention takes the following forms.

1) In the image reading device, an area where the document exists is detected in parallel with the image reading operation.

By taking this form, the image reading apparatus has an effect of generating image data from a document to be read and setting an image cutout area.

2) The area where the document exists is detected by the multi-value data monitor detecting the difference between the output of the CCD document and the output of the backing surface.

By adopting this mode, the image reading apparatus has an effect of generating image data from a document to be read and setting a cutout area of the image.

3) C to be monitored by the multi-value data monitor
The output value of the CD is regarded as a boundary in the width direction of the original when a difference between the output of the original and the backing surface on one scanning line is detected.

By taking this form, the image reading apparatus has an effect of setting a cut-out area in the width direction of the document to be read.

4) C to be monitored by the multi-value data monitor
The output value of the CD is regarded as a boundary in the longitudinal direction of the document at a point where all outputs of the CCD of one scanning line are at the level of the output value of the backing surface.

By taking this form, the image reading apparatus has an effect of setting a cutout area in the length direction of the original to be read.

5) In a document transport type image reading apparatus, a leading edge, a side edge and a trailing edge of a document are detected by a document detection sensor provided near an optical system for reading an image.

By adopting this form, the image reading apparatus has an effect of generating image data from a document to be read and setting an image cutout area.

6) The document detection sensor detects the leading edge of the document and the side edge of the document.

By taking this form, the image reading apparatus has an effect of setting a cutout area in the width direction of the original to be read at the same time as the start of image reading.

7) The document detection sensor calculates the transported distance of the document at a time interval from when the leading edge of the document is detected to when the trailing edge is detected, and the area in the length direction of the document is calculated. Set.

By taking this form, the image reading apparatus has an effect of setting a cutout area in the length direction of the original to be read at the same time as the end of the image reading.

8) The area in the width direction of the document set by the image reading apparatus is defined by the number of pixels read by the CCD.

By taking this form, an effect is obtained that the image data read by the image reading apparatus and the data in which the width of the cutout area of the image is set have the same counting unit.

9) The length area in the width direction of the original set by the image reading apparatus is defined by the number of scanning lines read by the CCD.

By taking this form, an effect is obtained that the image data read by the image reading apparatus and the data in which the length of the cutout area of the image is set have the same counting unit.

10) The image data read by the image reading device and the data of the image width and the image length in which the cutout area of the image is set are transferred to the host device.

By adopting this mode, the host device has an effect of receiving the image data read by the image reading device together with the cut-out area.

11) The procedure of displaying and storing the image data read by the host device based on the cut-out area by the host device is performed via the recording medium readable by the host device. To the host device as a part of the driver program.

By adopting this mode, the host device has an effect of providing a procedure for displaying and storing image data based on the cut-out area by connecting the image reading device.

[0081]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A representative embodiment according to the present invention will be described with reference to FIGS. 1 and 3 have already been described in the description of the image reading apparatus according to the related art, and thus will not be described here.

As shown in the block diagram of FIG. 4, the one-dimensional image data in the main scanning direction, which is the output of the CCD section B11 provided in the image reading device B10, is transferred to the operation control section B14 via the amplifier circuit B12, The data is accumulated by reading in the scanning direction and transferred to the host device B01 as two-dimensional image data.

The CCD section B is connected via an amplifier circuit B12.
The data of the width position of the document found by the data output from the multi-value data monitor B13 for monitoring the output of the counter 11 is retained in the counter B17 provided in the arithmetic control unit B14 until the reading is completed and the image data is transferred. Is done.

Arithmetic control unit B built in host device B01
02, the driver program B05 is fetched from the memory unit B04 in advance and the image reading device B10
In preparation for receiving image data to be transferred. The driver program B05 is provided from the image reading device B10 and stored in the memory B04 when the image reading device B10 is defined as a peripheral device connected to the host device B01.

The image data transferred from the image reading device B10 is displayed on a monitor B03, and the image data processed by the arithmetic control unit B02 is stored in an image buffer B07 of a RAM unit B06. You.

The flow of image reading will be described with reference to FIG. In the image reading device B10, when the image reading instruction is given, the CCD unit B11 reads the white reference in step S01, and notifies the multi-value data monitor B13 of the output via the amplifier circuit B12.

At step S02, the multi-value data monitor B1
In step 3, the arithmetic control unit B14 calculates the individual variation adjustment amount based on the output data collocated as one scan line output, sets the parameters of the amplifier circuit B12, and adjusts the gain of the CCD unit B11.

At step S03, reading of the document is started. The output of the CCD unit B11 is converted into image data by the arithmetic and control unit B14 via the amplifier circuit B12, and is input to the multi-value data monitor B13.
The difference between the CCD output of the document area and the backing surface among the scanning lines is examined to detect the boundary in the width direction of the document.

From the start of reading, the number of scanning lines to be read by main scanning is accumulated and stored in a counter B17 provided in the arithmetic and control unit B14.

Here, the process of detecting the boundary line in the width direction of the document by the above-described difference check will be described with reference to FIGS. 1 and 2.

As shown in FIG. 1A, the CCD 3 transfers image data to an arithmetic control unit (not shown) via an amplifier circuit (not shown) and transfers its output to a multi-value data monitor 4. .

As shown in FIG. 1B, the maximum length of the scanning line output from the CCD 3 is the width X of the effective reading area 2c.
The width Xb of the original area 1a does not exceed the width Xa of the effective reading area 2c.

As shown in FIG. 2A, when reading is started in accordance with an instruction, the CCD 3 sets the effective reading area 2
The data is read over the entire width Xa of c, and the output is transferred to the multi-value data monitor 4 (see FIG. 1A).

The multi-value data monitor 4 reads the data obtained by reading the original area 1a (see FIG. 1A) and the backing surface 2a (see FIG. 1A) from the output values obtained from the CCD 3. Identify differences from data.

The backing surface 2a has a uniform surface over the entire surface, and is given in advance as a sample value for comparing data of the output value of the CCD 3. Preferably, the backing surface 2a is colored in an appropriate color so that the backing surface 2a can be more clearly identified.

When the backing surface 2a is identified, the multi-valued data monitor 4 determines whether the document area 1a is in the main scanning direction.
The point at which the data is read and is switched to the backing surface 2a is defined as a document width boundary line 1b.

Further, the main scanning is repeated in the area of the distance Δy in the sub-scanning direction, and the point at which the data read from the original area 1a is switched to the backing surface 2a is confirmed in the area of the distance Δy. Border line 1
Determine b.

If the document width boundary line 1b can be determined,
In the read image data, areas other than the document area 1a are determined to be unnecessary image data, and in the subsequent reading, the document width boundary line 1 in the main scanning direction is used.
By ignoring the image data after b, the required memory capacity for storing the image data is compressed.

Returning to FIG. 6, the description of the image reading flow will be continued. In step S04, the process returns to step S03 to continue the checking operation until a document width boundary line is detected.

If the document width is set in step S05, the flow advances to step S06 to store the position of the pixel where the read document width boundary line exists, and correct the reading width.

The reading is further continued in step S07, but in this case, the read image data of the pixel which has exceeded the reading width by the main scanning is ignored.

In step S08, when the multi-value data monitor B13, which has monitored the output value of the CCD section B11 so far in parallel with the generation of the image data, reads the boundary line in the longitudinal direction of the original, the flow advances to step S09 to proceed to step S09. Set the length.

Here, the process in which the multi-value data monitor B13 detects a boundary in the length direction of the document will be described with reference to FIG. 2B.

When the scanning line for reading moves in the sub-scanning direction and passes the distance Yb from the reading start position, the original area 1a to be read runs out, so that the multi-value data monitor 4 (see FIG. 1) monitors. The output of the CCD 3 (refer to FIG. 1) is constituted only by reading the backing surface 2a.

Therefore, if the multi-value data monitor 4 confirms that the CCD 3 has read the backing surface 2a over the entire area of the scanning line, the switched scanning line is regarded as the original length boundary line.

Returning to FIG. 6, the description of the image reading flow will be continued. In step S08, the process returns to step S07 until the document length boundary is detected, and the checking operation is continued in parallel with the reading.

If the document length is set in step S09, the flow advances to step S10 to store the document length value with the accumulated value of the number of scanning lines stored in the counter B17, and the image reading operation is terminated.

In step S11, original width data set by the number of pixels and original length data set by the number of scanning lines are transferred to the host device B01 together with the read image data.

When the host device B01 receives the image data, the document width data set by the number of pixels, and the document length data set by the number of scanning lines from the image reading device in step S12, the host device B01 pulls it out of the memory B04 in advance and starts up. The driver program B05 sets the image width based on the document width data set by the number of pixels, and sets the image length based on the document length data set by the number of scanning lines. After determining the image area, the process proceeds to step S13 to display the image on the monitor B03 and
The image is stored in the image buffer B07 set in the M section B06.

As shown in the block diagram of FIG. 5, when the sensor B18 detects the leading edge of the document conveyed by the document conveying unit B19 provided in the image reading device B20, the image reading device B20 starts reading an image. The image reading is terminated when the sensor B18 detects the rear end of the document.

The one-dimensional image data in the main scanning direction, which is the output of the CCD unit B11, is transferred to the arithmetic and control unit B14 via the amplifier circuit B12, and is further accumulated by reading in the sub-scanning direction. Transferred to B01.

The CCD section B is connected via an amplifier circuit B12.
The data on the width position of the document found by the data output from the multi-value data monitor B13 monitoring the output of the data 11 is held in the counter B17 provided in the arithmetic control unit B14 from the end of the reading until the transfer of the image data. You.

Arithmetic control unit B built in host device B01
02, the driver program B05 is fetched from the memory unit B04 in advance and the image reading device B20 is read out.
In preparation for receiving image data to be transferred. The driver program B05 is provided from the image reading device B20 and stored in the memory unit B04 when defining the image reading device B20 as a peripheral device connected to the host device B01.

The image data transferred from the image reading device B20 is displayed on a monitor B03, and the image data processed by the arithmetic control unit B02 is stored in an image buffer B07 of a RAM unit B06. You.

The flow of image reading will be described with reference to FIG. In the image reading device B20, when the image reading instruction is given, in step S21, the CCD unit B11 reads the white reference at the position facing the CCD unit B11, and notifies the multi-value data monitor B13 of the output via the amplifier circuit B12.

In step S22, the multi-value data monitor B1
In step 3, the arithmetic control unit B14 calculates the individual variation adjustment amount based on the output data collocated as the output of one scanning line, sets the parameters of the amplifier circuit B12, and adjusts the gain of the CCD unit B11.

In step S23, the document transport section B19 starts transporting the document.

When the conveyed document is applied to the sensor B18, the sensor B18 detects the leading end of the document in step S24, and after a predetermined time, returns to step S25.
To read the original in accordance with the original conveyance.

The output of the CCD section B11 is supplied to an amplifier circuit B12.
Is converted into image data by the arithmetic control unit B14, and is input to the multi-value data monitor B13. Then, the process proceeds to step S26, in which the CC between the original area and the backing surface in one scanning line is determined.
By examining the difference between the D outputs, a boundary line in the width direction of the document is detected.

The flow from step S26 to step S28 is the same as the flow from step S04 to step S06 of the flow described above with reference to FIG. 6, and the setting of the document width is also equivalent. Therefore, the description of the flow from step S26 to step S28 will be omitted.

When the sensor B18 detects the trailing edge of the original in step S29, the counter B is detected in step S30.
The document length is set based on the number of scanning lines accumulated since the start of reading at 17.

In step S31, the above document length value is stored, the image reading is completed, and the flow advances to step S32 to read the document image data together with the read image data and the document width data set by the number of pixels and the document length set by the number of scanning lines. And the data to the host device B01.

When the host device B01 receives the image data, the document width data set by the number of pixels, and the document length data set by the number of scanning lines from the image reading device in step S33, the host device B01 pulls it out of the memory B04 in advance and starts up. The driver program B05 sets the image width based on the document width data set by the number of pixels, and sets the image length based on the document length data set by the number of scanning lines. After determining the image area, the process advances to step S34 to display the image on the monitor B03 and
The image is stored in the image buffer B07 set in the M section B06.

The flow of image reading will be described with reference to FIG. Here, the corresponding block diagram is shown in FIG.

In the image reading device B20, when an instruction to read an image is given, in step S36, the CCD section B1 is read.
1 reads a white reference at a position facing the multi-value data monitor B13 via an amplifier circuit B12.
Notify.

In step S37, the multi-value data monitor B1
In step 3, the arithmetic control unit B14 calculates the individual variation adjustment amount based on the output data collocated as the output of one scanning line, sets the parameters of the amplifier circuit B12, and adjusts the gain of the CCD unit B11.

In step S38, the document transport section B19 starts transporting the document.

When the conveyed document is applied to the sensor B18 having a detection unit juxtaposed in the main scanning direction, in step S39, the sensor B18 detects the leading edge of the document and simultaneously detects the existence range of the document in the main scanning direction. I do. Further, after the predetermined time, the process proceeds to step S40, and reading of the document is started in accordance with the document conveyance.

The number of scanning lines after the start of image reading is accumulated in the counter B17 and stored.

In step S41, the width of the original is set based on the existence range of the original detected by the sensor B18. In step S42, the width of the original is replaced with the number of pixels and stored. Is corrected in accordance with the number of pixels, and the read image data other than the original is ignored.

If the sensor B18 detects the trailing end of the document in step S43, the flow advances to step S44 to use the number of scanning lines accumulated and stored in the counter B17 until that time as the length data of the document.

In step S45, the document length data based on the number of scanning lines is stored, and the image reading ends.

In step S46, the original width data based on the number of pixels and the original length data based on the number of scanning lines are transferred to the host device B01 together with the image data obtained by reading the original.

When the host device B01 receives the image data, the document width data set by the number of pixels and the document length data set by the number of scanning lines from the image reading device in step S47, the host device B01 pulls it out of the memory B04 in advance and starts up. The driver program B05 sets the image width based on the document width data set by the number of pixels, and sets the image length based on the document length data set by the number of scanning lines. After the image area is determined, the process proceeds to step S48, where the image is displayed on the monitor B03 and RA
The image is stored in the image buffer B07 set in the M section B06.

[0135]

According to the present invention, the following effects can be expected.

1) In the image reading device, the area where the document exists is detected in parallel with the image reading operation.

By taking this means, the image reading apparatus generates image data from the document to be read and sets the cutout area of the image, so that the image data can be minimized. Since the amount of memory used in the image reading device is minimized and the amount of image data transferred to the host device is suppressed to a necessary minimum, the time required for transfer is shortened.

2) The area where the document exists is detected by the multi-value data monitor detecting the difference between the output of the CCD document and the output of the backing surface.

By taking this means, the image reading apparatus produces image data from a document to be read, and has the effect of setting an image cutout area in parallel with the image reading operation. .

3) C to be monitored by the multi-value data monitor
The output value of the CD is regarded as a boundary in the width direction of the original when a difference between the output of the original and the backing surface on one scanning line is detected.

By taking this means, the image reading apparatus has an effect of setting the cutout area in the width direction of the original to be read along the range in which the original exists.

4) C to be monitored by the multi-value data monitor
The output value of the CD is regarded as a boundary in the longitudinal direction of the document at a point where all outputs of the CCD of one scanning line are at the level of the output value of the backing surface.

By adopting this means, the image reading apparatus has an effect of setting the cutout area in the length direction of the original to be read along the range where the original exists.

5) In a document feed type image reading apparatus, a document detection sensor provided near an optical system for reading an image detects the leading edge, side edge and rear edge of the document.

By taking this means, the image reading apparatus has an effect of generating image data from a document to be read and setting a cutout area of the image.

6) The document detection sensor detects the leading edge of the document and also detects the side edge of the document.

By taking this means, the image reading apparatus has an effect of setting the cutout area in the width direction of the original to be read at the same time as the start of image reading.

7) The document detection sensor calculates the transported distance of the document with a time interval from when the leading edge of the document is detected to when the trailing edge is detected, and the area in the length direction of the document is calculated. Set.

By taking this means, the image reading apparatus has an effect of setting the cutout area in the length direction of the original to be read at the same time as the end of the image reading.

8) The area in the width direction of the document set by the image reading apparatus is defined by the number of pixels read by the CCD.

By taking this means, an effect is obtained that the image data read by the image reading apparatus and the data in which the width of the cutout area of the image is set have the same counting unit.

9) The length region in the width direction of the document set by the image reading apparatus is defined by the number of scanning lines read by the CCD.

By taking this means, an effect is obtained in that the image data read by the image reading device and the data in which the length of the cutout area of the image is set have the same counting unit.

10) The image data read by the image reading device and the data of the image width and the image length in which the cutout area of the image is set are transferred to the host device.

By taking this means, the host device has the effect of receiving the image data read by the image reading device together with the cut-out area.

11) The procedure for displaying and storing the image data read by the image reading device based on the cut-out area by the host device is performed via the recording medium readable by the host device. To the host device as a part of the driver program.

By taking this means, the host device has the effect of providing a procedure for displaying and storing image data based on the cut-out area by connecting the image reading device.

[Brief description of the drawings]

FIG. 1 is an explanatory diagram of image reading (1).

FIG. 2 is an explanatory diagram of image reading (2).

FIG. 3 is an explanatory diagram of image reading (3).

FIG. 4 is a block diagram (1) of a typical embodiment of the present invention.

FIG. 5 is a block diagram (2) according to a representative embodiment of the present invention.

FIG. 6 is a flowchart (1) according to a representative embodiment of the present invention.

FIG. 7 is a flowchart (2) according to a representative embodiment of the present invention.

FIG. 8 is a flowchart (3) according to the representative embodiment of the present invention.

FIG. 9 is a block diagram according to a conventional technique (1).

FIG. 10 is a block diagram (2) according to a conventional technique.

FIG. 11 is a flowchart (1) according to a conventional technique.

FIG. 12 is a flowchart (2) according to a conventional technique.

FIG. 13 is a flowchart (3) according to a conventional technique.

[Explanation of symbols]

 1: Document 1a: Document area 1b: Document width boundary 1c: Document length boundary 2: Backing 2a: Backing surface 2c: Effective reading area 3: CCD 4: Multi-value data monitor B01: Host device B02: Operation Control unit B03: Monitor B05: Driver program B07: Image buffer B10, B20: Image reading device B11: CCD unit B13: Multi-value data monitor B14: Operation control unit B17: Counter B18: Sensor B19: Document transport unit

Claims (12)

[Claims] In a control method of an image reading device for reading an image written on a document and providing image data to a host device, an effective reading area (2c) provided in the image reading device in parallel with the image reading operation. A method for detecting an original area (1a) and setting a cutout area of an image. 2. A document area (1a) in the effective reading area (2c) includes a backing surface (2a) on which a multi-value data monitor (4) holds the document (1) and the document (1).
The method according to claim 1, wherein the setting is performed by detecting a difference between outputs of the CCD (3) and the output of the CCD (3). 3. The multi-value data monitor (4) has a difference between the output of the CCD (3) on the same scanning line at the time when the image reading device starts reading and the original (1) and the backing surface (4). 3. The method according to claim 2, wherein a boundary between the image reading device and the image reading device is determined by setting a boundary between the document width and the original document. 4. The multi-value data monitor (4) detects when all the output values of the CCD (3) on the same scanning line have reached the level of the output value of the backing surface (2a). 3. The control method for an image reading apparatus according to claim 2, wherein a document length boundary line (1c) is set. 5. An original document area (1a) in the effective reading area (2c) is provided with a sensor (1) provided in the vicinity of an optical system (10) for conveying the original document (1) and reading an image.
2. The method according to claim 1, wherein the setting is performed by detecting a leading edge, a side edge, and a trailing edge of the document.
3. The method for controlling an image reading device according to claim 1. 6. The sensor (12) detects passage of the leading edge of the document (1) when the image reading apparatus starts reading, and detects a range of the document (1) in the main scanning direction. The method according to claim 5, wherein the width of the document (1) is set upon detection. 7. The sensor (12) detects the leading edge of the document (1) when the image reading apparatus starts reading, and determines the elapsed time until the trailing edge of the document (1) is detected. The method according to claim 5, wherein the length of the document (1) is set. 8. The width of the original area (1a) set by the image reading device is the same as the width of the CC provided in the image reading device.
The method according to any one of claims 1 to 7, wherein the image data is defined by the number of pixels to be read in D (3). 9. The length of the document area (1a) set by the image reading device is the same as the length of the C provided in the image reading device.
The method according to any one of claims 1 to 7, wherein the image data is defined by the number of scanning lines read by the CD (3). 10. The data of the number of pixels indicating the width of the original area (1a) and the data of the number of scanning lines indicating the length of the original area (1a) set by the image reading apparatus are used for the image reading apparatus. 2. The method according to claim 1, wherein the image data is transferred to the host device together with the image data obtained by reading the document. 11. The image data transferred from the image reading device to the host device together with the image data, the pixel number data indicating the width of the document area (1a) and the length of the document area (1a). The method for controlling an image reading device according to claim 10, wherein a procedure for cutting out the image area is provided to the host device based on the scanning line number data indicating the following. 12. An original area (1a) in an effective reading area (2c) provided in an image reading apparatus in parallel with an image reading operation when reading an image written on the original and providing image data to a host device. ) Is detected, an image cutout area is set, data indicating the image cutout area is transmitted to the host device together with the image data, and the read image is displayed and stored in the host device based on the image cutout area. A computer-readable recording medium storing a control program for an image reading apparatus having a procedure for performing the above steps.