JP2021129168A - Image forming apparatus - Google Patents

Abstract

To automatically set a magnification ratio when using a crop function in an image forming apparatus in which the number of image processing circuits to be mounted is limited, and prevent reduction in image quality.SOLUTION: In a crop mode, a control unit generates second image data for printout on the basis of first image data for printout. A printer unit performs printing on the basis of the second image data for printout. The control unit recognizes size of a document placed and determines a magnification ratio. An image processing circuit performs magnification processing on read image data with the magnification ratio before performing halftone processing to generate the first image data for printout. The control unit performs processing for cutting out a document portion from the first image data for printout to generate the second image data for printout.SELECTED DRAWING: Figure 7

Description

The present invention relates to an image forming apparatus that processes image data obtained by reading a document.

There is an image reading device that uses an image sensor to read a document and generate image data. Then, some image reading devices automatically cut out the original portion from the image data and correct the inclination of the original portion. Patent Document 1 describes an example of an apparatus that automatically cuts and corrects tilt of a document portion.

Specifically, in Patent Document 1, a rectangular area including an area where a document exists is extracted from the scanned image, the inclination of the rectangular area is detected, and the inclination of the rectangle is corrected according to the detected inclination. death,
The cut width of each side of the rectangle is set according to the detected inclination, and based on the set cut width of each side, the peripheral part of the rectangular area is cut out as a document image, and one of the main scanning directions of the rectangular area is obtained. Described is an image reading device that sets the cutting width larger than a predetermined reference value according to the degree of inclination detected based on the side of the image. With this configuration, even if the manuscript is tilted, the image of the manuscript is automatically cut out so as not to cut too much and a part of the manuscript is not chipped (Patent Document 1: Claim 1, Claim 2, [0010], [0011]).

Japanese Patent No. 3903932

An image forming apparatus including a scanner and a printing unit can copy a document (for example, a multifunction device). The scanner scans the document. The printing unit prints based on the image data obtained by scanning the original. As one of the copy functions, there is also an image forming apparatus that can use a crop function (automatic cropping processing function). The crop function is a function of cutting out the original part from the image data obtained by reading the original and printing the cut out original part. When using the crop function, if the magnification is set automatically, it is useful for copying small documents such as cards. The automatic enlargement ratio setting function is a function that automatically enlarges the cut-out original portion so that it fits on the paper used for printing.

Here, a plurality of types of image processing are performed until the printing unit generates image data (image data for print output) used for printing from the image data obtained by scanning. For example, halftone processing is performed. Halftone processing is also called halftone dot processing. In the printing apparatus, basically, binary output is performed in which a color material is placed or not placed on the paper in units of one pixel. For example, the coloring material is toner or ink. By scanning, image data having a gradation value (pixel value) can be obtained. By the halftone processing, image data in which the value of each pixel is 1 (with a color material) or 0 (without a color material) is generated. The printing apparatus prints based on the image data subjected to the halftone processing. Normally, in the halftone processing, a device is made to express the shading by the density of the dots.

Image processing of image data after halftone processing may result in poor image quality. For example, when the image data subjected to the halftone processing is enlarged, the lines constituting the characters become not smooth. Therefore, the halftone processing is usually performed at the final stage of the process of generating image data for print output.

When the enlargement ratio is automatically calculated in the crop mode, it is necessary to recognize the size of the original part. Based on the size of the recognized original part, the enlargement ratio is set so that it fits on the paper used. In order to recognize the size of the original portion, it is necessary to once expand the image data for one page into a memory such as RAM and analyze the image data for one page.

Image forming devices in the medium to high price range are often equipped with a plurality of integrated circuits (image processing circuits) for processing images. Each integrated circuit has a different role, type of image processing to be executed, and order of execution of image processing. By setting the integrated circuit that performs halftone processing as the final stage, the image data in the generation process is once expanded in RAM, the size of the original part is recognized, the enlargement ratio is determined, the enlargement processing is performed, and then the halftone processing is performed. Can be applied.

However, in a low-priced (low-end) image forming apparatus, it may not be possible to mount a plurality of integrated circuits (image processing circuits) for processing images. In other words, various image processing circuits may be combined into one integrated circuit. In the case of a copy job, such an image processing circuit processes the input image data. The image processing circuit outputs image data that has undergone halftone processing, which is essential for printing. That is, one chip performs image processing up to the form of supplying to the printing unit.

In order to automatically determine the enlargement ratio, it is necessary to recognize the size of the original part. In the low-end image forming apparatus, the image data used for size recognition of the original portion may be the image data after the halftone processing. After recognizing the size of the original portion and determining the enlargement ratio, the image data after the halftone processing is enlarged. In a low-priced (low-end) image forming apparatus, there is a problem that the image quality of image data may deteriorate when the magnification is automatically set by the crop function.

Patent Document 1 does not describe any of enlarging the extracted manuscript portion, automatically setting the enlarging ratio, and performing halftone processing. The technique described in Patent Document 1 cannot solve the above problem.

In view of the above-mentioned problems of the prior art, the present invention makes it possible to automatically set the enlargement ratio when the crop function is used in an image forming apparatus in which the number of image processing circuits mounted is limited, while preventing the image quality from deteriorating. do.

In order to solve the above problems, the image forming apparatus according to the present invention includes an operation panel, a scanner unit, an image processing circuit, a memory, a control unit, and a printer unit. The operation panel accepts user operations. The operation panel accepts the selection of crop mode. The scanner unit includes a platen and a line sensor. The scanner unit reads a document set on the platen. The image processing circuit generates image data for the first print output. The memory stores the generated image data for the first print output. In the crop mode, the control unit generates the second print output image data based on the first print output image data. The printer unit prints based on the image data for the second print output. The image processing circuit includes a halftone processing circuit and a zoom processing circuit. The image processing circuit generates the first print output image data obtained by subjecting the scanned image data obtained by reading the scanner unit to halftone processing. When the crop mode is selected, the control unit recognizes the size of the document set in the scanner unit before scanning to generate the first print output image data. Based on the recognized size of the original, the control unit determines the enlargement ratio so that the length of the short side or the long side of the original becomes a size corresponding to the print range of the paper used for printing. The image processing circuit enlarges the read image data at a predetermined enlargement ratio, and then performs the halftone process to generate the first print output image data. When the first print output image data is generated, the control unit performs a cutting process of cutting out a document portion from the first print output image data to generate the second print output image data.

According to the present invention, the enlargement ratio can be automatically set when the crop function is used in an image forming apparatus in which the number of image processing circuits mounted is limited. It is possible to provide an image forming apparatus in which the image quality does not deteriorate even if the enlargement ratio is automatically set.

It is a figure which shows an example of the image forming apparatus which concerns on embodiment. It is a figure which shows an example of the scanner part which concerns on embodiment. It is a figure which shows an example of the scanner part which concerns on embodiment. It is a figure which shows an example of the process flow at the time of reading a document by the image forming apparatus which concerns on embodiment. It is a figure which shows an example of the scanner part which concerns on embodiment. It is a figure which shows an example of the difference of image quality by execution order of image processing. It is a figure which shows an example of the process flow in the size selection mode which concerns on embodiment. It is a figure which shows an example of the image data for the 1st print output which concerns on embodiment. It is a figure which shows an example of the image data for the 2nd print output which concerns on embodiment. It is a figure which shows an example of the warning screen which concerns on embodiment. It is a figure which shows an example of the process flow in the 1st image quality priority mode which concerns on embodiment. It is a figure which shows an example of the process flow in the 2nd image quality priority mode which concerns on embodiment. It is a figure which shows an example of the explanatory screen which concerns on embodiment. It is a figure which shows an example of the process flow in the speed priority mode which concerns on embodiment.

Hereinafter, the image forming apparatus 100 according to the embodiment will be described with reference to FIGS. 1 to 14. The image forming apparatus 100 described below includes a scanner unit 5 and a printer unit 4. The image forming apparatus 100 can perform a print job based on the image data obtained by reading the original (copy job). For example, the image forming apparatus 100 is a multifunction device. Each element such as the configuration and the arrangement described in the description of the present embodiment does not limit the scope of the invention and is merely an example of description.

(Image forming apparatus 100)
The image forming apparatus 100 according to the embodiment will be described with reference to FIG. FIG. 1 is a diagram showing an example of an image forming apparatus 100 according to an embodiment.

As shown in FIG. 1, the image forming apparatus 100 includes a control unit 1, a storage unit 2, an operation panel 3, a printer unit 4, and a scanner unit 5.

The control unit 1 controls the operation of the image forming apparatus 100. The control unit 1 controls the operation of the image forming apparatus 100 in the job. For example, the control unit 1 is a substrate including a control circuit 10, an image data generation circuit 11, an image processing circuit 6, and a communication circuit unit 12. The control circuit 10 is, for example, a CPU. The control circuit 10 performs processing and calculation related to the job. The image data generation circuit 11 processes the analog image signal that the scanner unit 5 reads the document and outputs, and generates the scanned image data. The image processing circuit 6 performs image processing on the image data used for printing and generates image data for print output. For example, the scanned image data is input to the image processing circuit 6.

The communication circuit unit 12 includes a communication control circuit, a connector, and a communication memory. The communication memory stores communication software. The communication circuit unit 12 communicates with the computer 200 and the fax device 300. For example, the computer 200 is a PC and a server. The communication circuit unit 12 receives print data sent from the computer 200 or the fax device 300. The control unit 1 causes the printer unit 4 to print based on the received print data (print job, fax reception printing). Further, in the case of a transmission job, the operation panel 3 accepts the setting of the destination. The control unit 1 causes the communication circuit unit 12 to transmit an image file based on the image data obtained by reading toward the set destination (scan transmission, FAX transmission).

The storage unit 2 includes a RAM 21 (corresponding to a memory), a ROM 22, and a storage 23. The control circuit 10 reads the program and data from the ROM 22 or the storage 23 into the RAM 21. The control circuit 10 processes using the program and data read into the RAM 21. The storage unit 2 includes a ROM 22 and a storage 23 as a non-volatile storage device. For example, the storage 23 is an HDD or SSD. The control unit 1 controls each unit based on the programs and data stored in the storage unit 2.

The operation panel 3 accepts the user's settings. The operation panel 3 includes a display panel 31, a touch panel 32, and a hard key 33. The control unit 1 displays a message, a setting screen, and an operation image on the display panel 31. Operational images are, for example, buttons, keys, and tabs. Based on the output of the touch panel 32, the control unit 1 recognizes the operated operation image. The hard key 33 includes a start key and a numeric keypad. The touch panel 32 and the hard key 33 accept the user's setting operation (job-related operation). For example, the operation panel 3 accepts the setting of the reading mode of the original. Based on the output of the operation panel 3, the control unit 1 recognizes the setting contents.

The printer unit 4 includes a paper feeding unit 41, a paper conveying unit 42, an image forming unit 43, and a fixing unit 44. The paper feed unit 41 includes a paper feed cassette and a paper feed roller. The paper cassette holds paper. The paper feed roller feeds out the paper. At the time of a print job, the control unit 1 rotates the paper feed roller to supply paper. The paper transport unit 42 includes a transport roller pair for paper transport and a transport motor. The transfer motor rotates a pair of transfer rollers. At the time of printing, the control unit 1 rotates the transfer motor and the transfer roller pair. The control unit 1 conveys the paper to the paper conveying unit 42.

For example, the image forming unit 43 includes a photoconductor drum, a charging device, an exposure device, a developing device, and a transfer roller. Based on the image data, the control unit 1 causes the image forming unit 43 to form a toner image. The control unit 1 uses a transfer roller to transfer the toner image to the conveyed paper. The fixing unit 44 includes a heater, a fixing rotating body, and a fixing motor. The heater heats the fixing rotating body. The paper is conveyed while being in contact with the fixing rotating body. As a result, the toner image is fixed on the paper. The control unit 1 causes the fixing unit 44 to fix the transferred toner image on the paper. The paper transport unit 42 discharges the printed paper to the outside of the machine.

(Scanner unit 5)
Next, an example of the scanner unit 5 according to the embodiment will be described with reference to FIGS. 2 and 3. 2 and 3 are views showing an example of the scanner unit 5 according to the embodiment. FIG. 2 is a view of the scanner unit 5 according to the embodiment as viewed from the front direction of the image forming apparatus 100.

A platen 5a (contact glass for reading a table) is provided above the scanner unit 5. The platen 5a is a transparent plate (glass plate). When scanning the table, the user sets the document on one side of the platen 5a (the upper side in FIG. 2).

The document cover 51 is provided above the scanner unit 5. The document cover 51 can be opened and closed so that the front side of the image forming apparatus 100 is shaken up and down. The user opens the document cover 51 and sets the document. After setting, the user closes the document cover 51. FIG. 2 shows a state in which the document cover 51 is closed. A holding plate 52 is attached to the lower surface of the document cover 51. For example, the holding plate 52 is a white plate. When the document cover 51 is closed, the holding plate 52 covers the document base 5a and the set document from above. The pressing plate 52 presses the document from above so that the document does not move. That is, the document cover 51 holds the document.

As shown in FIG. 3, the scanner unit 5 includes a read control unit 50. The reading control unit 50 receives a document reading instruction from the control unit 1. The reading control unit 50 is a substrate that controls the operation of the scanner unit 5. The read control unit 50 includes a CPU (read control circuit) and a memory. The scanner unit 5 includes a carriage 53 and a moving mechanism. The moving mechanism includes a belt 54, a pulley 55, a pulley 56, and a moving motor 57. The carriage 53 is a CIS type scan unit. The scanner unit 5 may have a CCD scan unit.

The belt 54 is endless. The belt 54 is hung around the pulley 55 and the pulley 56. The belt 54 and the carriage 53 are connected. A moving motor 57 is provided in the scanner unit 5 (see FIG. 3). The drive of the moving motor 57 is transmitted to the pulley 55 or the pulley 56. The moving motor 57 can rotate in the forward and reverse directions. When moving the carriage 53, the reading control unit 50 rotates the moving motor 57. As a result, the belt 54 goes around. The carriage 53 moves in the horizontal direction (sub-scanning direction, direction perpendicular to the main scanning direction, left-right direction in FIG. 2) in accordance with the rotation of the belt 54. The carriage 53 moves on the other side (lower side) of the platen 5a.

The white reference plate 58 is provided on the outside of the platen 5a in the sub-scanning direction. The longitudinal direction of the white reference plate 58 is the main scanning direction. A home position is set on the carriage 53. The home position is set within a range in which the position of the reading line of the carriage 53 (line sensor 510) becomes the white reference plate 58. In FIG. 2, the carriage 53 is located in the home position.

The carriage 53 includes a first lamp 59a, a second lamp 59b, a line sensor 510, and a transmission circuit 511. The carriage 53 also includes a lens 512 (rod lens array) that guides the reflected light to each light receiving element of the line sensor 510. The first lamp 59a and the second lamp 59b irradiate the reading target (document, holding plate 52, white reference plate 58) with light along the main scanning direction. The lamp to be provided may be only one of the first lamp 59a and the second lamp.

The reading control unit 50 includes a lighting control circuit 50a. The lighting control circuit 50a controls the lighting of the first lamp 59a and the second lamp 59b. When reading a document, the control unit 1 gives a document reading instruction to the lighting control circuit 50a. Based on this instruction, the lighting control circuit 50a turns on and off the first lamp 59a and the second lamp 59b while reading the document.

The line sensor 510 reads the original placed on the platen 5a. The line sensor 510 reads a reading target (original document, holding plate 52, white reference plate 58). For example, the line sensor 510 is one (for black / white). In addition, three line sensors 510, R, G, and B, may be provided so that the object to be read (original) can be read in color.

The line sensor 510 includes a plurality of light receiving elements (photoelectric conversion elements, pixels). The light receiving element receives the light reflected by the reading target. The light receiving elements are arranged in a row. The direction in which the light receiving elements are lined up is the main scanning direction. Each light receiving element outputs an analog image signal (analog voltage) according to the amount of light received (reflected light amount). Each light receiving element outputs a larger analog image signal as the amount of light received during the reading period increases.

(Process flow when scanning a document)
Next, an example of the processing flow at the time of reading the original by the image forming apparatus 100 according to the embodiment will be described with reference to FIG. FIG. 4 is a diagram showing an example of a processing flow at the time of reading a document by the image forming apparatus 100 according to the embodiment.

The image forming apparatus 100 can execute a job (a job involving reading a document) using the scanner unit 5. Jobs using the scanner unit 5 include, for example, a copy job and a scan transmission. The copy job is a job that generates print output image data based on the image data (scanned image data) obtained by scanning and prints based on the print output image data. The scan transmission job is a job of generating an image file based on the image data obtained by scanning and transmitting the generated image file. An example of the processing flow at the time of executing a copy job will be described below.

The carriage 53 includes a transmission circuit 511. The transmission circuit 511 is, for example, a shift register. The transmission circuit 511 extracts the electric charge of each light receiving element of the line sensor 510 stored during the reading period of one line. Then, the transmission circuit 511 sends (inputs) the extracted electric charge as an analog image signal to the image data generation circuit 11. The image data generation circuit 11 may be provided in the scanner unit 5.

The image data generation circuit 11 is connected to the transmission circuit 511 by a cable. The image data generation circuit 11 includes a plurality of circuits. For example, the image data generation circuit 11 includes an amplifier circuit 11a, an A / D conversion circuit 11b, and a correction circuit 11c. The amplifier circuit 11a amplifies the input analog image signal. The amplified analog image signal is input to the A / D conversion circuit 11b. The A / D conversion circuit 11b converts the input analog image signal into a digital image signal. That is, the image data generation circuit 11 (A / D conversion circuit 11b) A / D-converts the analog image signal output from the line sensor 510 to generate the read image data.

The correction circuit 11c corrects the generated scanned image data. For example, the correction circuit 11c includes a shading correction circuit 11c to perform shading correction. The correction circuit 11c may include other types of correction circuits. The image data generation circuit 11 outputs the corrected read image data. The output scanned image data is input to the image processing circuit 6.

For example, the image processing circuit 6 is an ASIC. In order to reduce the manufacturing cost, in the image forming apparatus 100, in the copy job, only one integrated circuit (image processing circuit 6) is used to process the scanned image data obtained by scanning to generate image data for print output. be. The image processing circuit 6 includes a plurality of circuit blocks. Each circuit block is a circuit (hardware) that performs image processing. Each circuit block differs in the content of image processing to be executed. That is, the image processing circuit 6 is an integrated circuit in which a plurality of circuits for image processing having different processing contents are integrated into one.

The image processing circuit 6 includes a zoom processing circuit 61 and a halftone processing circuit 62 as circuit blocks. The zoom processing circuit 61 is a circuit for enlarging or reducing image data. The halftone processing is a circuit that performs halftone processing by the error diffusion method. In addition, the image processing circuit 6 may include, as a circuit block, a circuit for performing image processing necessary for generating image data for print output. For example, a circuit for converting RGB format read image data to CMYK format and a circuit for converting RGB format read image data to luminance (monochrome, gray) format may be included.

In the case of a copy job, when the scanned image data is input to the image processing circuit 6, the image processing circuit 6 performs various image processing and finally performs halftone processing. In the case of a copy job, the image processing circuit 6 processes the input scanned image data and outputs the image data for print output.

The image data for print output is image data to be delivered to the printer unit 4 (exposure apparatus of the image forming unit 43). The image data for print output is binary image data that has undergone halftone processing (halftone dot processing). The value of each pixel is a value indicating whether toner (coloring material) is applied (exposed) or not (not exposed). Based on the image data for print output, the image forming unit 43 (exposure apparatus) exposes the photoconductor drum in pixel units. As a result, a toner image (image) obtained by copying the scanned image data is printed.

The control unit 1 stores the print output image data generated by the image processing circuit 6 in the RAM 21 of the storage unit 2. The control unit 1 supplies image data for print output from the RAM 21 to the image forming unit 43 (exposure apparatus) in accordance with the timing of forming the toner image. If there is image processing that could not be performed by the image processing circuit 6, the control unit 1 (control circuit 10) performs image processing that the control circuit 10 could not perform on the print output image data of the RAM 21. Image data for print output may be supplied to the image forming unit 43.

(Set of manuscript)
Next, an example of a document set in the image forming apparatus 100 according to the embodiment will be described with reference to FIG. FIG. 5 is a diagram showing an example of the scanner unit 5 according to the embodiment. In FIG. 5, the document cover 51 is not shown.

The user places (sets) the original on the platen 5a. The user has the reading surface facing down. FIG. 5 shows an example of a state in which a small original (special original) such as a business card or a card is set. As shown in FIG. 5, a reference point P is set on the platen 5a. The reference point P is the left back corner of the platen 5a when the scanner unit 5 (image forming apparatus 100) is viewed from the front. When the platen 5a is viewed from above, the reference point P is the upper left corner of the platen 5a. For example, when placing a standard size document, the user aligns the upper left corner of the document with the reference point P. The long side of the platen 5a is parallel to the sub-scanning direction. The short side of the platen 5a is parallel to the main scanning direction.

When reading a document, the control unit 1 moves the carriage 53 to the moving mechanism from one side to the other side of the side (end) facing each other in the sub-scanning direction of the document base 5a. The side closer to the reference point P is one side of the platen 5a. In FIG. 5, an example of the position of the reading line at the home position is shown by a broken line. The carriage 53 that has moved from the home position starts scanning from the scanning start line on one side of the platen 5a. The reading start line passes through the reference point P. In FIG. 5, the traveling direction of the carriage 53 when reading (scanning) a document is illustrated by a solid arrow. When the document reading is completed, the control unit 1 moves the carriage 53 to the moving mechanism toward the home position. The control unit 1 reverses the traveling direction and returns the carriage 53 to the home position.

The control unit 1 moves the carriage 53 at a predetermined speed. The moving speed of the carriage 53 is a value obtained by dividing the reading width of one line (pitch of one pixel and one dot) by the reading cycle of one line. That is, the control unit 1 moves the carriage 53 by 1 dot for each read cycle of one line.

(Crop mode)
The outline of the crop mode according to the embodiment will be described with reference to FIG. FIG. 6 is a diagram showing an example of a difference in image quality depending on the execution order of image processing.

The image forming apparatus 100 is equipped with (can be used) a crop mode. Crop mode is a type of copy job. The operation panel 3 accepts the selection of the crop mode. Based on the output of the operation panel 3, the control unit 1 recognizes that the crop mode has been selected.

In the crop mode, the control unit 1 causes the scanner unit 5 to read the document set on the platen 5a. The control unit 1 automatically cuts out (cuts out) the document portion D1 from the scanned image data obtained by scanning. The control unit 1 prints the cut out portion on paper. An enlarged image of the original is printed. The crop mode is a mode in which copying of a card document is taken into consideration.

A card manuscript is a small card. For example, a card manuscript is a card used as an identification card such as a driver's license, a health insurance card, or an ID card. Passports, credit cards, and cash cards can also be treated as card manuscripts. In addition, business cards and cards collected as a hobby (for example, cards of athletes) can also be treated as card manuscripts. An original that is smaller in size than the smallest paper that can be printed by the image forming apparatus 100 may be treated as a card original.

The general user does not always know the size of the document (card) to be read in the crop mode. Therefore, it is conceivable to recognize the size of the document portion D1 (card portion) and automatically set the enlargement magnification based on the ratio of the recognized size of the document portion D1 to the size of the paper used for printing. In other words, it is conceivable to enable the automatic enlargement ratio setting function in crop mode.

In the image forming apparatus 100 of the present embodiment, in the case of a copy job, when the scanned image data is input, the image processing circuit 6 generates print output image data that has undergone halftone processing. Based on the image data for print output, the size of the original portion D1 can be recognized and the enlargement ratio can be determined. However, the enlargement process is performed after the halftone process. It is known that the image quality may deteriorate when the enlargement processing is performed after the halftone processing. FIG. 6 shows a comparative example of image data in which image processing is performed in the order of halftone processing → enlargement processing and image data in which image processing is performed in the order of enlargement processing → halftone processing. In the example of FIG. 6, there are many characters in which the smoothness of the line is lost and the unevenness becomes stronger when the enlargement processing is performed after the halftone processing.

Middle-class and high-class devices are usually equipped with a plurality of integrated circuits (ASICs) for image processing. When the automatic scaling function is installed in the crop mode, for example, it is possible to avoid the enlargement processing after the halftone processing as follows. For example, the image data is processed by the integrated circuit for image processing in the first stage without performing halftone processing. The enlargement ratio is determined based on the image data after the first stage processing. After applying the enlargement ratio determined by the integrated circuit for image processing in the second and subsequent stages to perform the enlargement processing, the halftone processing is performed. Each integrated circuit for image processing shares a role (type of image processing to be executed). In this way, even if the automatic enlargement ratio setting function is used in the crop mode, it is not necessary to perform the enlargement processing after the halftone processing.

The image forming apparatus 100 has one image processing circuit 6 mounted on the image forming apparatus 100. One is that when a copy job is performed in the crop mode, the enlargement ratio can be set automatically without causing deterioration in image quality. When the crop mode is selected, the operation panel 3 accepts the selection of the mode to be used from the size selection mode, the first image quality priority mode, the second image quality priority mode, and the speed priority mode. The control unit 1 recognizes the selected mode from the size selection mode, the first image quality priority mode, the second image quality priority mode, and the speed priority mode. The control unit 1 performs processing according to the selected mode. Hereinafter, each mode will be described.

(Size selection mode)
An example of the processing flow in the size selection mode according to the embodiment will be described with reference to FIGS. 7 to 10. FIG. 7 is a diagram showing an example of a processing flow in the size selection mode according to the embodiment. FIG. 8 is a diagram showing an example of the first print output image data i1 according to the embodiment. FIG. 9 is a diagram showing an example of the second print output image data i2 according to the embodiment. FIG. 10 is a diagram showing an example of the warning screen S1 according to the embodiment.

When using the size selection mode, the user selects the crop mode on the operation panel 3. Next, among the modes that can be selected in the crop mode, the user selects the size selection mode on the operation panel 3. Based on the output of the operation panel 3, the control unit 1 recognizes that the size selection mode of the crop mode has been selected.

First, the control unit 1 (control circuit 10) displays a size selection screen (not shown) on the display panel 31 (step # 11). The size selection screen is a screen for selecting the size of the document (card) to be read in the crop mode.

Here, there is ISO / IEC 7810 as an international standard for card size. In ISO / IEC 7810, three main sizes are defined. The first is a size of 85.60 mm x 53.98 mm. Credit cards and cash cards are this first size. The second is A7 size (105 mm x 74 mm). Paper of this size is used for small notebooks, memos, and party seating cards. The third is B7 size (125 mm x 88 mm). Passports and visas are the third size. On the size selection screen, one of these three sizes may be selected. Based on the output of the operation panel 3, the control unit 1 (control circuit 10) recognizes the size of the document set in the scanner unit 5 (step # 12).

Based on the recognized document size, the control unit 1 (control circuit 10) obtains the enlargement ratio (step # 13). Specifically, the control unit 1 (control circuit 10) recognizes the size of the paper used in the crop mode (copy). The control unit 1 may recognize the size of the paper used for printing based on the output of the paper size sensor provided in the paper feed unit 41. Further, the operation panel 3 may accept the size of the paper used for printing. In this case, the control unit 1 recognizes the paper size accepted by the operation panel 3 as the size of the paper used for printing.

Next, the control unit 1 (control circuit 10) recognizes the size of the print range A1 of the paper used for printing. For example, the print range A1 is rectangular. The image forming apparatus 100 does not print to the very limit of the paper. That is, no borderless printing is performed. The print range A1 is an area of the paper excluding the non-printable range. For example, it is a range including four edges of a rectangle of paper, and a range having a width of 1 to several mm is a range in which printing is not performed. For example, when the width of the non-printing portion is 5 mm, the control unit 1 recognizes the value obtained by subtracting 10 mm from the long side of the paper used for printing as the size of the long side of the print range A1. Further, the control unit 1 recognizes the value obtained by subtracting 10 mm from the short side of the paper used for printing as the size of the short side of the print range A1.

The control unit 1 (control circuit 10) divides the length of the long side of the print range A1 by the length of the long side of the recognized document size to obtain the first division value. The control unit 1 (control circuit 10) divides the length of the short side of the print range A1 by the length of the short side of the recognized document size to obtain the second division value. The control circuit 10 defines the smaller of the first division value and the second division value as the enlargement ratio. As a result, the contents of the enlarged manuscript fit on the paper. An appropriate magnification can be set automatically.

The control unit 1 (control circuit 10) causes the scanner unit 5 to read (step # 14). The reading range in crop mode is predetermined. The control unit 1 may have the scanner unit 5 read the entire surface of the document base 5a. Further, the control unit 1 may have the scanner read about half of the platen 5a. The user sets the document within the scanning range. Based on the analog image signal output from the scanner unit 5, the control unit 1 (image data generation circuit 11) generates the scanned image data (step # 15).

The image processing circuit 6 enlarges the read image data at a predetermined enlargement ratio, and after the enlargement processing, performs halftone processing to generate the first print output image data i1 (step # 16). The control unit 1 stores the generated first print output image data i1 in the RAM 21 (step # 17). The first print output image data i1 is image data that has undergone halftone processing and has not undergone cutting processing or tilt correction processing. FIG. 7 shows an example of the first print output image data i1. As shown in FIG. 7, the document may be placed at an angle.

The control unit 1 (control circuit 10) generates the second print output image data i2 by performing the tilt correction process and the cutout process of the first print output image data i1 (step # 18). The control circuit 10 executes software (program) that performs tilt correction processing and cutting processing. Without using the image processing circuit 6, the control circuit 10 executes image processing using software to generate the second print output image data i2.

Originals such as cards are thick. The light reflection of the lamp is disturbed by the step in the thick part. As a result, as shown in FIG. 8, in the first print output image data i1, the pixels at the edge of the original (card) become high density (dark and black). The control circuit 10 searches for four straight lines corresponding to the edges of the document. For example, the control circuit 10 performs a Hough transform process to search for a straight line. Then, the control circuit 10 searches for the intersection of straight lines. The control circuit 10 has a point on the long side of the first print output image data i1 and a point on the other side of the intersection, and a short side direction of the first print output image data i1. The four points, the point on one side and the point on the other side, are recognized as the coordinates of the four corners of the document portion D1 (rectangular). The control circuit 10 recognizes a quadrangle (rectangle) having the recognized straight line as the outer circumference and the recognized four corners as the vertices as the document portion D1.

Then, the control circuit 10 performs tilt correction processing and cutting processing. For example, the control circuit 10 obtains the inclination of a straight line connecting two points on the edge and recognizes the inclination angle of the document portion D1. Then, the control circuit 10 determines a correction angle at which the inclination disappears. For example, the control circuit 10 obtains the angle of a straight line connecting the upper left corner and the upper right corner with reference to the upper left corner of the document portion D1 in the first print output image data i1. When the straight line is tilted 10 degrees clockwise with respect to the upper left corner, the control circuit 10 defines 10 degrees counterclockwise as the correction angle.

For example, the control circuit 10 performs an affine transformation process, and performs a tilt correction process and a cut process. The control circuit 10 generates a code that rotates by a correction angle with respect to any corner of the document portion D1 or the center of the document portion D1 as a base point, and includes the code in the affine transformation processing program. The control circuit 10 generates image data obtained by performing affine transformation processing in the range of the document portion D1 as the second print output image data i2. As a result, the second print output image data i2 obtained by performing the tilt correction process and the cut process on the document portion D1 can be obtained.

FIG. 9 is a diagram showing an example of the second print output image data i2. The manuscript portion D1 can be enlarged so that the contents do not protrude from the paper. Further, the inclination is also corrected so that the edge of the document portion D1 is parallel to the edge of the image data (paper).

The control unit 1 (control circuit 10) confirms whether or not the entire image data i2 for the second print output falls within the print range A1 of the paper used for printing (step # 19). In other words, the control unit 1 (control circuit 10) confirms whether or not the size of the second print output image data i2 is larger than the size of the print range A1 of the paper used for printing. When the second print output image data i2 does not fit in the print range A1 (No in step # 19), the control unit 1 (control circuit 10) displays the warning screen S1 on the display panel 31 (step # 110).

FIG. 10 shows an example of the warning screen S1. As shown in FIG. 10, the control unit 1 (control circuit 10) displays the warning message M1 in the warning screen S1. The warning message M1 is a message notifying that a part of the content may be cut when printed. Further, the control unit 1 displays the continuation button B1 and the print cancel button B2 in the warning screen S1. If a part of the content may be cut, the user may operate the continuation button B1. If you do not want to print, the user may operate the print cancel button B2. The user operates any button.

The control unit 1 (control circuit 10) confirms whether or not the operated button is the continuation button B1 (step # 111). When the second print output image data i2 falls within the print range A1 (No in step # 19) and when the operation panel 3 accepts the continuation of processing (Yes in step # 111), the control unit 1 (control circuit). 10) causes the printer unit 4 to perform printing based on the second print output image data i2 (step # 112). In the crop mode, the enlargement ratio is automatically determined, and printing can be performed based on the image data that has undergone halftone processing after the enlargement processing. On the other hand, when the operation panel 3 accepts the cancellation of the process (No in step # 111), the control unit 1 (control circuit 10) does not print based on the second print output image data i2 on the printer unit 4. , End the process (end). The user can start over.

(1st image quality priority mode)
An example of the processing flow in the first image quality priority mode according to the embodiment will be described with reference to FIG. FIG. 11 is a diagram showing an example of a processing flow in the first image quality priority mode according to the embodiment.

When using the first image quality priority mode, the user selects the crop mode on the operation panel 3. Next, among the modes that can be selected in the crop mode, the user selects the first image quality priority mode on the operation panel 3. Based on the output of the operation panel 3, the control unit 1 recognizes that the first image quality priority mode is selected in the crop mode.

The control unit 1 (control circuit 10) causes the scanner unit 5 to perform the first reading (step # 21). The scanner unit 5 reads the reading range in the crop mode. The user sets the document within the scanning range. Based on the analog image signal output from the scanner unit 5, the control unit 1 (image data generation circuit 11) generates the scanned image data (step # 22).

The image processing circuit 6 generates size detection image data based on the scanned image data obtained in the first reading (step # 23). The image processing circuit 6 generates image data that has undergone halftone processing without enlarging the scanned image data as size detection image data. The generated size detection data is stored in the RAM 21.

The control unit 1 (control circuit 10) recognizes the size of the document set in the scanner unit 5 based on the size detection image data (step # 24). The size recognition method is the same as the size selection mode. Specifically, the control circuit 10 searches for four straight lines corresponding to the edges of the document. Then, the control circuit 10 searches for the intersection of straight lines. The control circuit 10 is located on one side of the intersections on the long side direction of the size detection image data and on the other side, and on the short side side in the short side direction of the size detection image data. The four points on the opposite side of the point are recognized as the coordinates of the four corners (vertices of the rectangle) of the document portion D1.

The control unit 1 (control circuit 10) obtains the size of the document based on the recognized vertices of the rectangle. For example, the control unit 1 selects any one vertex in the size detection image data. For example, the control unit 1 selects the apex in the upper left corner. The control unit 1 obtains the lengths of two straight lines connected to the selected vertices. The unit of length is the number of pixels. The control unit 1 obtains the length of the document by multiplying the pitch of one pixel at the reading resolution by the obtained length. In the case of 600 dpi, the pitch of one pixel is 25.4 mm ÷ 600 ≈ 42.3 μm. The control unit 1 recognizes the longer of the obtained lengths as the length of the long side of the document. The control unit 1 recognizes the shorter of the obtained lengths as the length of the short side of the document.

The control unit 1 (control circuit 10) obtains the enlargement ratio based on the recognized original size (side length) (step # 25). The method of determining the enlargement ratio is the same as that of the size selection mode. Specifically, the control unit 1 (control circuit 10) recognizes the size of the paper used in the crop mode (copy). Next, the control unit 1 recognizes the size of the print range A1 of the paper used for printing. The control unit 1 divides the length of the long side of the print range A1 by the length of the long side of the recognized document to obtain the first division value. Further, the control unit 1 divides the length of the short side of the print range A1 by the length of the short side of the recognized document to obtain the second division value. The control circuit 10 defines the smaller of the first division value and the second division value as the enlargement ratio.

The control unit 1 (control circuit 10) causes the scanner unit 5 to perform a second reading (step # 26). Based on the analog image signal output from the scanner unit 5, the control unit 1 (image data generation circuit 11) generates the scanned image data (step # 27).

The image processing circuit 6 enlarges the read image data at a predetermined enlargement ratio, and after the enlargement processing, performs halftone processing to generate the first print output image data i1 (step # 28). The control unit 1 stores the generated first print output image data i1 in the RAM 21 (step # 29). Then, the control unit 1 (control circuit 10) performs tilt correction processing and cutting processing of the first print output image data i1 of the RAM 21 to generate the second print output image data i2 (step # 210).

The process of step # 210 may be the same as that of step # 18 of the size selection mode. The control circuit 10 executes software (program) that performs tilt correction processing and cutting processing. Specifically, the control circuit 10 searches for four straight lines corresponding to the edges of the document. Then, the control circuit 10 searches for the intersection of straight lines. The control circuit 10 has a point on the long side of the first print output image data i1 and a point on the other side of the intersection, and a short side direction of the first print output image data i1. The four points, the point on the onemost side and the point on the other side, are recognized as the coordinates of the four corners (the vertices of the quadrangle) of the document portion D1. The control circuit 10 recognizes a quadrangle (rectangle) having the recognized straight line as the outer circumference and the recognized four corners as the vertices as the document portion D1.

The control circuit 10 performs tilt correction processing and cutting processing. The control circuit 10 recognizes the tilt angle of the document portion D1. Then, the control circuit 10 determines the correction angle. For example, the control circuit 10 performs an affine transformation process, and performs a tilt correction process and a cut process. The control circuit 10 generates a code that rotates by a correction angle with respect to any corner of the document portion D1 or the center of the document portion D1 as a base point, and includes the code in the affine transformation processing program. The control circuit 10 outputs the image data obtained by performing the affine transformation processing in the range of the document portion D1 as the second print output image data i2. As a result, the second print output image data i2 obtained by performing the tilt correction process and the cut process on the document portion D1 can be obtained.

The control unit 1 (control circuit 10) causes the printer unit 4 to print based on the second print output image data i2 (step # 211 → end). As a result, in the crop mode, the enlargement ratio is automatically determined, and printing can be performed based on the image data obtained by halftone processing after the enlargement processing. In the first image quality priority mode, the original can be read twice and the exact size of the original can be recognized. Therefore, it is not necessary to confirm whether or not the second print output image data i2 falls within the print range A1.

(Second image quality priority mode)
An example of the processing flow in the second image quality priority mode according to the embodiment will be described with reference to FIGS. 12 and 13. FIG. 12 is a diagram showing an example of a processing flow in the second image quality priority mode according to the embodiment. FIG. 13 is a diagram showing an example of the explanatory screen S2 according to the embodiment.

When using the second image quality priority mode, the user selects the crop mode on the operation panel 3. Next, among the modes that can be selected in the crop mode, the user selects the second image quality priority mode on the operation panel 3. Based on the output of the operation panel 3, the control unit 1 recognizes that the second image quality priority mode is selected in the crop mode.

First, the control unit 1 (control circuit 10) displays the explanation screen S2 on the display panel 31 (step # 31). In the second image quality priority mode, a part of the document is read to recognize the size of the document in the main scanning direction. It is necessary to set the document so that the size in the main scanning direction can be accurately recognized. The explanation screen S2 is a screen for explaining a method of setting a document in the second image quality priority mode.

FIG. 13 shows an example of the explanation screen S2. As shown in FIG. 13, the control unit 1 may display a message prompting that the main scanning direction and the sub-scanning direction should be set so that the sides of the document are parallel to each other in accordance with the reference point P. Further, the control unit 1 may display a message for matching the orientations of the document and the paper (the orientations of the long side and the short side). Further, the control unit 1 may display a message for closing the document cover 51 for the detection scan.

By closing the document cover 51 of the user, the scanner unit 5 performs a detection scan (step # 32). The detection scan is a scan for detecting the size of a document in the main scanning direction. In the detection scan, the scanner unit 5 scans a part of the document before the document cover 51 is completely closed (when the document cover 51 is closed to a predetermined angle or less).

The scanner unit 5 is provided with an open / close detection sensor (see FIGS. 1 and 5). For example, the open / close detection sensor includes an actuator. The actuator comes into contact with the lower surface of the document cover 51 and changes its position according to the opening / closing angle of the document cover 51. Due to the displacement of the actuator, the output level of the open / close detection sensor changes when the document cover 51 is closed below a predetermined angle and when the document cover 51 is opened more than a predetermined angle. The output of the open / close detection sensor is input to the control unit 1. When it is recognized that the document cover 51 is closed by a predetermined angle or less, the control unit 1 causes the scanner unit 5 to execute a detection scan.

In the detection scan, the scanner unit 5 reads a position on the platen 5a, which is separated from the reference point P by a predetermined length in the sub-scanning direction. For example, the predetermined length is several millimeters. The scanned image data for one line can be obtained by the detection scan. When the scanned image data is input, the image processing circuit 6 generates the scanned image data for detection (step # 33). At this time, the image processing circuit 6 does not perform the enlargement processing.

The control unit 1 (control circuit 10) recognizes the size of the set document in the main scanning direction based on the scan image data for detection (step # 34). For example, in the scan image data for detection, the light of the lamp is not reflected by the holding plate 52 in the portion where there is no document. Therefore, the part without the original has a dark (black, high density) value. On the other hand, the pixel value of a certain part of the document is a bright (white, low density) value. Based on a predetermined threshold value, the control unit 1 (control circuit 10) recognizes the boundary between the low density pixel and the high density pixel. The control unit 1 may recognize the size of the set document in the main scanning direction by multiplying the number of pixels from the boundary to the pixel corresponding to the reference point P by the pitch of one pixel at the reading resolution.

The control unit 1 (control circuit 10) obtains the enlargement ratio based on the size of the recognized document in the main scanning direction (step # 35). Specifically, the control unit 1 (control circuit 10) recognizes the size of the paper used in the crop mode (copy). Next, the control unit 1 recognizes the size of the print range A1 of the paper to be used. The control unit 1 divides the length of the print range A1 in the main scanning direction by the length of the recognized document in the main scanning direction to obtain a division value. The control unit 1 determines the division value as the enlargement ratio.

The control unit 1 (control circuit 10) causes the scanner unit 5 to read (step # 36). The control unit 1 causes the reading range in the crop mode to be read. Based on the analog image signal output from the scanner unit 5, the control unit 1 (image data generation circuit 11) generates the scanned image data (step # 37).

The image processing circuit 6 enlarges the read image data at a predetermined enlargement ratio, and after the enlargement processing, performs halftone processing to generate the first print output image data i1 (step # 38). The control unit 1 stores the generated first print output image data i1 in the RAM 21 (step # 39). Subsequently, the control unit 1 (control circuit 10) performs tilt correction processing and cutting processing of the first print output image data i1 of the RAM 21 to generate the second print output image data i2 (step #). 310). The process of step # 310 may be the same as step # 18 of the size selection mode and step # 210 of the first image quality priority mode.

The control unit 1 (control circuit 10) causes the printer unit 4 to print based on the second print output image data i2 (step # 311 → end). In the second image quality priority mode, the control unit 1 recognizes the document size and determines the enlargement ratio. Therefore, it is not necessary to confirm whether or not the second print output image data i2 falls within the print range A1.

(Speed priority mode)
An example of the processing flow in the speed priority mode according to the embodiment will be described with reference to FIG. FIG. 14 is a diagram showing an example of a processing flow in the speed priority mode according to the embodiment.

When using the speed priority mode, the user selects the crop mode on the operation panel 3. Next, among the modes that can be selected in the crop mode, the user selects the speed priority mode on the operation panel 3. Based on the output of the operation panel 3, the control unit 1 recognizes that the speed priority mode is selected in the crop mode.

The control unit 1 (control circuit 10) causes the scanner unit 5 to read (step # 41). Before the scanning of the scanner unit 5 is started, the user sets the original. The scanner unit 5 reads the reading range in the crop mode. Based on the analog image signal output from the scanner unit 5, the control unit 1 (image data generation circuit 11) generates the scanned image data (step # 42).

The image processing circuit 6 performs halftone processing without enlarging the scanned image data to generate the first print output image data i1 (step # 43). The control unit 1 stores the generated first print output image data i1 in the RAM 21 (step # 44).

The control unit 1 (control circuit 10) recognizes the size of the document set in the scanner unit 5 based on the first print output image data i1 (step # 45). Specifically, the control circuit 10 searches for four straight lines corresponding to the edges of the document. For example, the control circuit 10 performs a Hough transform process to search for a straight line. Then, the control circuit 10 searches for the intersection of straight lines. The control circuit 10 has a point on the long side of the first print output image data i1 and a point on the other side of the intersection, and a short side direction of the first print output image data i1. The four points, the point on the onemost side and the point on the other side, are recognized as the coordinates of the four corners (the vertices of the quadrangle) of the document portion D1.

The control unit 1 (control circuit 10) obtains the size of the document based on the recognized vertices of the rectangle. For example, the control unit 1 selects any one vertex in the first print output image data i1. For example, the control unit 1 selects the upper left vertex. The control unit 1 obtains the lengths of two straight lines connected to the selected vertices. The unit of length is the number of pixels. The control unit 1 obtains the length of the document by multiplying the pitch of one pixel at the reading resolution by the obtained length. The control unit 1 recognizes the longer one as the length of the long side of the document and the shorter one as the length of the short side of the document.

Then, the control unit 1 (control circuit 10) obtains the enlargement ratio based on the recognized size (side length) of the document (step # 46). The method of determining the enlargement ratio is the same as that of the size selection mode, the first image quality priority mode, and the second image quality priority mode. Specifically, the control unit 1 (control circuit 10) recognizes the size of the paper used in the crop mode (copy) and the size of the print range A1. The control unit 1 (control circuit 10) divides the length of the long side of the print range A1 by the length of the long side of the recognized document to obtain the first division value. Further, the control unit 1 (control circuit 10) divides the length of the short side of the print range A1 by the length of the short side of the recognized document to obtain the second division value. The control circuit 10 defines the smaller of the first division value and the second division value as the enlargement ratio.

The control unit 1 (control circuit 10) generates the second print output image data i2 by performing enlargement processing, tilt correction processing, and cutting processing of the first print output image data i1 of the RAM 21 (step # 47). ). The control circuit 10 executes software (program) that performs enlargement processing, tilt correction processing, and cutting processing. Without using the image processing circuit 6, the control circuit 10 executes image processing using software to generate the second print output image data i2.

For example, the control circuit 10 obtains the inclination of a straight line connecting two points on the edge and recognizes the inclination angle of the document portion D1. Then, the control circuit 10 determines a correction angle at which the inclination disappears. Then, the control circuit 10 performs an affine transformation process, and performs an enlargement process, an inclination correction process, and a cutting process. The control circuit 10 generates a code that enlarges the document portion D1 by a predetermined enlargement ratio. Further, the control circuit 10 generates a code for rotating the document portion D1 by a correction angle with respect to any corner of the document portion D1 or the center of the document portion D1 as a base point. The control circuit 10 includes the generated code in the affine transformation processing program. The control circuit 10 executes a program for affine transformation processing. The control circuit 10 outputs the image data obtained by performing the affine transformation processing in the range of the document portion D1 as the second print output image data i2. As a result, of the first print output image data i1, the second print output image data i2 obtained by performing enlargement processing, tilt correction processing, and cutting processing on the original portion D1.

The control unit 1 (control circuit 10) causes the printer unit 4 to print based on the second print output image data i2 (step # 48). In the speed priority mode, exceptionally, the image data that has undergone halftone processing is enlarged. However, among the modes that can be selected in the crop mode, the printed matter obtained by copying the original (card) can be obtained earliest.

In this way, the image forming apparatus 100 according to the embodiment includes an operation panel 3, a scanner unit 5, an image processing circuit 6, a memory, a control unit 1, and a printer unit 4. The operation panel 3 accepts the user's operation. The operation panel 3 accepts the selection of the crop mode. The scanner unit 5 includes a platen 5a and a line sensor 510. The scanner unit 5 reads a document set on the platen 5a. The image processing circuit 6 generates the first print output image data i1. The memory stores the generated first print output image data i1. In the crop mode, the control unit 1 generates the second print output image data i2 based on the first print output image data i1. The printer unit 4 prints based on the second print output image data i2. The image processing circuit 6 includes a halftone processing circuit 62 and a zoom processing circuit 61. The image processing circuit 6 generates the first print output image data i1 obtained by subjecting the scanned image data obtained by the scanning of the scanner unit 5 to halftone processing. When the crop mode is selected, the control unit 1 recognizes the size of the document set in the scanner unit 5 before scanning to generate the first print output image data i1. Based on the recognized size of the document, the control unit 1 determines the enlargement ratio so that the length of the short side or the long side of the document becomes a size corresponding to the print range A1 of the paper used for printing. The image processing circuit 6 enlarges the read image data at a predetermined enlargement ratio, and then performs the halftone process to generate the first print output image data i1. When the first print output image data i1 is generated, the control unit 1 performs a cutting process of cutting out the original portion D1 from the first print output image data i1 to perform the second print output image data i2. To generate.

The original size can be recognized before scanning the original for generating the first print output image data i1. For example, the size of the card set in the platen 5a can be recognized. Based on the recognized size of the original, the enlargement ratio of the cropped (cut out) portion can be automatically determined before reading the original for generating the first print output image data i1. With the determined enlargement ratio, it is possible to obtain the first print output image data i1 that has undergone the enlargement processing and then the halftone processing. It is possible to prevent image processing from being performed in the order in which the image quality deteriorates. Even if the low-end image forming apparatus 100 is equipped with a crop function and an automatic enlargement ratio setting function, deterioration of image quality can be prevented. Even if the number of image processing circuits 6 installed is limited (even if only one), the image forming apparatus 100 may have a function of automatically setting the enlargement ratio so that the image quality does not deteriorate in the crop mode. can.

When the operation panel 3 accepts the document size setting after selecting the crop mode, the control unit 1 recognizes the document size set by the operation panel 3 as the size of the document set in the scanner unit 5. .. Before scanning the document in crop mode, the size of the loaded document can be recognized. Based on the size of the document selected by the user, an appropriate magnification can be determined before scanning with halftone processing.

The image forming apparatus 100 includes a display panel 31. When the size of the second print output image data i2 is larger than the print range A1, the control unit 1 may cut a part of the content when printing before printing based on the second print output image data i2. A warning message M1 notifying that there is a possibility is displayed on the display panel 31. It is possible to warn of the possibility of an error in the size of the document set by the user. It is possible to warn before the start of printing that a part of the content of the original may protrude and a part may not be printed.

When the operation panel 3 accepts the continuation of the process after displaying the warning message M1, the control unit 1 causes the printer unit 4 to print based on the second print output image data i2. When the operation panel 3 accepts the cancellation, the control unit 1 does not allow the printer unit 4 to print based on the second print output image data i2. When the warning message M1 is displayed, it is possible to select whether to continue or stop printing. Since you can choose to stop printing, you can eliminate unnecessary printing. It is possible to eliminate wasteful consumption of paper and coloring materials.

After selecting the crop mode, when the operation panel 3 accepts the selection of the first image quality priority mode, the control unit 1 causes the scanner unit 5 to perform the first document scanning. The image processing circuit 6 generates image data for size detection by performing halftone processing on the scanned image data obtained by the first document scanning without performing enlargement processing. The control unit 1 recognizes the size of the set document based on the size detection image data. The control unit 1 determines the enlargement ratio based on the recognized size of the original. After determining the enlargement ratio, the control unit 1 causes the scanner unit 5 to read the document for the second time. The image processing circuit 6 generates image data i1 for the first print output by performing halftone processing after performing enlargement processing at a predetermined enlargement ratio on the scanned image data obtained by the second original scanning. .. By reading the original document for the first time, the size of the original document can be accurately recognized. The appropriate magnification can be set automatically without sticking out of the paper. Based on the second reading and the determined enlargement ratio, image processing can be performed in the order of enlargement processing and halftone processing. Even if the image forming apparatus 100 in which the number of image processing circuits 6 is mounted is equipped with the crop function and the automatic enlargement ratio setting function, it is possible to obtain a printed matter without deterioration in image quality.

The scanner unit 5 includes a document cover 51. The document cover 51 can be opened and closed, and when closed, holds the document set on the document base 5a. After selecting the crop mode, when the operation panel 3 accepts the selection of the second image quality priority mode, the scanner unit 5 is a part of the document set in the document table 5a before the opened document cover 51 is completely closed. Perform a detection scan to read. Based on the detection scan image data obtained by the detection scan, the control unit 1 recognizes the size of the document set in the platen 5a in the main scanning direction. The enlargement ratio is determined so that the size of the document recognized by the detection scan in the main scanning direction becomes the size of the printing range A1 in the main scanning direction. After determining the enlargement ratio, the control unit 1 causes the scanner unit 5 to read the entire document set. The image processing circuit 6 generates the first print output image data i1 which is subjected to halftone processing after performing enlargement processing at a predetermined enlargement ratio on the scanned image data obtained by scanning the entire document. .. By scanning for detection (scanning a part of the document), the size of the document in the main scanning direction can be accurately recognized. The enlargement ratio can be automatically set so that the cropped document portion D1 does not protrude from the paper. It is possible to obtain image data that has been image-processed in the order of enlargement processing and halftone processing based on the reading of the entire document after the detection scan and the determined enlargement ratio. Even if the image forming apparatus 100 in which the number of image processing circuits 6 is mounted is equipped with the crop function and the automatic enlargement ratio setting function, it is possible to obtain a printed matter without deterioration in image quality.

After selecting the crop mode, when the operation panel 3 accepts the selection of the speed priority mode, the control unit 1 is set in the scanner unit 5 before reading for generating the first print output image data i1. Does not recognize the size of the original. The control unit 1 causes the scanner unit 5 to read the entire document set. The image processing circuit 6 generates the first print output image data i1 by performing halftone processing on the scanned image data obtained by scanning the entire document without performing enlargement processing. The control unit 1 recognizes the size of the set document based on the first print output image data i1 that has not been enlarged. The control unit 1 determines the enlargement ratio based on the size of the recognized document. The control unit 1 generates the second print output image data i2 by performing the enlargement processing and the cutting process of the original portion D1 on the first print output image data i1 at a predetermined enlargement ratio. When obtaining a printed matter in which the original portion D1 is enlarged in the crop mode, it is possible to make a selection that gives priority to speed. Although there is a risk of image quality deterioration, it is possible to select printing that is fast.

The present invention can be used in an image forming apparatus.

100 Image forming device 1 Control unit 21 RAM (memory) 3 Operation panel 4 Printer unit 5 Scanner unit 5a Document stand 51 Document cover 510 Line sensor 6 Image processing circuit 61 Zoom processing circuit 62 Halftone processing circuit i1 Image for first print output Data i2 Image data for 2nd print output M1 Warning message

Claims (7)

An operation panel that accepts user operations and crop mode selection,
A scanner unit that includes a platen and a line sensor and reads the document set on the platen,
An image processing circuit that generates image data for the first print output,
A memory for storing the generated image data for the first print output, and
In the crop mode, a control unit that generates image data for the second print output based on the image data for the first print output, and a control unit.
Includes a printer unit that prints based on the second print output image data.
The image processing circuit
Includes halftone processing circuit and zoom processing circuit,
The scanned image data obtained by scanning the scanner unit is subjected to halftone processing to generate the first print output image data.
When the crop mode is selected
The control unit
Before scanning to generate the image data for the first print output, the size of the document set in the scanner unit is recognized, and the size of the document is recognized.
Based on the recognized size of the original, the enlargement ratio is determined so that the length of the short side or the long side of the original becomes a size corresponding to the print range of the paper used for printing.
The image processing circuit performs the enlargement processing of the read image data at a predetermined enlargement ratio, and then performs the halftone processing to generate the image data for the first print output.
When the first print output image data is generated, the control unit performs a cutting process of cutting out a document portion from the first print output image data to generate the second print output image data. An image forming apparatus as a feature. When the operation panel accepts the document size setting after selecting the crop mode,
The image forming apparatus according to claim 1, wherein the control unit recognizes the size of the document set on the operation panel as the size of the document set in the scanner unit. Including display panel
When the size of the image data for the second print output is larger than the print range
The control unit is characterized in that, before printing based on the second print output image data, a warning message notifying that a part of the content may be cut when printing is displayed on the display panel. The image forming apparatus according to claim 2. After displaying the warning message,
When the operation panel accepts the continuation of processing
The control unit causes the printer unit to perform printing based on the image data for the second print output.
When the operation panel accepts cancellation
The image forming apparatus according to claim 3, wherein the control unit does not allow the printer unit to perform printing based on the second print output image data. After selecting the crop mode, when the operation panel accepts the selection of the first image quality priority mode,
The control unit causes the scanner unit to read the document for the first time.
The image processing circuit generates image data for size detection by performing the halftone processing on the scanned image data obtained by the first scanning of the original without performing the enlargement processing.
The control unit
Based on the size detection image data, the size of the set document is recognized and
Based on the recognized size of the manuscript, the enlargement ratio is determined.
After determining the enlargement ratio, the scanner unit is made to read the document for the second time.
The image processing circuit performs the enlargement processing at the predetermined enlargement ratio on the read image data obtained by the second reading of the original, and then performs the halftone processing for the first print output. The image forming apparatus according to any one of claims 1 to 4, wherein the image data is generated. The scanner unit includes a document cover.
The document cover is openable and closable, and when closed, holds the document set on the document stand.
When the operation panel accepts the selection of the second image quality priority mode after selecting the crop mode,
The scanner unit performs a detection scan for reading a part of the document set on the platen before the opened document cover is completely closed.
The control unit
Based on the detection scan image data obtained by the detection scan, the size of the document set on the platen in the main scanning direction is recognized.
The enlargement ratio is determined so that the size of the document recognized by the detection scan in the main scanning direction becomes the size of the printing range in the main scanning direction.
After determining the enlargement ratio, the entire document set in the scanner unit is read.
The image processing circuit is used for the first print output in which the scanned image data obtained by scanning the entire document is subjected to the enlargement processing at a predetermined enlargement ratio and then the halftone processing. The image forming apparatus according to any one of claims 1 to 5, wherein the image data is generated. When the operation panel accepts the selection of the speed priority mode after the selection of the crop mode,
The control unit
Before scanning to generate the image data for the first print output, the size of the document set in the scanner unit is not recognized, and the size of the document is not recognized.
Have the scanner read the entire document set in the scanner unit.
The image processing circuit generates the first print output image data by performing the halftone processing without performing the enlargement processing on the scanned image data obtained by scanning the entire document.
The control unit
Based on the image data for the first print output that has not been enlarged, the size of the set original is recognized.
Based on the recognized size of the manuscript, the enlargement ratio is determined.
The first to sixth aspects of claim 1 to 6, wherein the image data for the first print output is enlarged and the cutout process of the original portion is performed at the determined enlargement ratio to generate the image data for the second print output. The image forming apparatus according to any one item.

Images