JPH10336437A - Image forming device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To apply gradation processing to both image areas of an image and a background automatically by separating the image area from the background area so as to generate a density change of binary image data by a pseudo halftone. SOLUTION: A halftone arithmetic section 1 (106) sums binary background area data stored in a surrounding pixel storage section 1 (105) with each other to detect a pseudo halftone density of a range. A binarizing circuit 1 (107) binarizes the halftone density calculated by the halftone arithmetic section 1 (106) and gives the result to an area discrimination section 1 (103) and a selection section 1 (104) as background arithmetic data. A mask section 110 compares a threshold level fed from a CPU 101 with data converted into a pseudo medium tone density. When the pseudo halftone density data are larger than the threshold level, the range is discriminated to be an 'image area' and when the threshold level is larger, the range is discriminated to be a 'background area'.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an image forming apparatus, and more particularly, to an image forming apparatus for forming image data, such as a digital copying machine, a digital printing machine, and a printer.

[0002]

2. Description of the Related Art Conventionally, a gradation process for increasing a visual effect by giving a density gradient to image data in one of image editing functions provided in a copying machine or the like and generating pseudo halftone image data. There is.

[0003] As a general processing method of the gradation processing, there is a "digital conversion apparatus and image forming apparatus" of Japanese Patent Application No. 8-145066 in which gradation processing is performed using a multi-valued image signal. This conventional example converts input data in which one pixel is expressed by a plurality of effective bit widths into operation data expressed by an effective bit width equal to the effective bit width, and converts the converted operation data and the input data. Integration is performed to calculate integrated data having a bit width twice the effective bit width, and the multiplication result is output by the same effective bit width as the input data, thereby reducing an error change in output data of the data conversion device. It is characterized by:

As a conventional example of performing a gradation process using a binarized signal, there is an "image data processing apparatus" disclosed in Japanese Patent Application No. Hei 8-332040. Is added to the image data before the predetermined number of pixels, and halftone operation data is calculated according to the halftone setting value given by the control means to the addition result. The output data of the pixel to be processed is output by comparing the output data of each pixel of the number of pixels with the total value of the output data of the pixels. Data can be generated.

[0005]

However, there are two types of gradation processing performed on image data and those performed on background data. The gradation processing is performed using the multi-valued image signal of the above-described conventional example. In a digital conversion device and an image forming device, gradation processing can be performed on both image areas of image data and background data. However, in a conventional image data processing device that performs gradation processing using a binary signal, image data is converted into image data. The gradation processing can be performed only on the background data, and the gradation processing cannot be performed on the background data.

The present invention separates an image area and a background area from input image data and forms a density change due to a pseudo halftone of binary image data, thereby automatically providing gradation to both image and background image areas. It is an object of the present invention to provide an image forming apparatus which can perform processing and can form an image in an arbitrary range in the main scanning direction and the sub-scanning direction.

[0007]

To achieve the above object, an image forming apparatus according to the present invention comprises: a halftone calculating means for determining a pseudo halftone degree of binary background area data;
The binary image data and the 2
Two types of area identification means for identifying whether the area corresponding to the image data and the background arithmetic data is an “image” or a “background” area using the value background arithmetic data, and performing an image forming operation And a control unit for controlling each of the units. The selection unit includes image data, background calculation data, and two types of data. When the identification result by the area identification means is input and the control means receives a designation of which of the two types of area identification means to select, the image is identified as "image" according to the designated area identification result. It is characterized in that image data is output to the region that has been set, and background calculation data is output to the region that is identified as “background”.

The area identification means inputs the image data and the background calculation data and converts each of them into binary pseudo-halftone density data, and converts the converted binary pseudo-halftone density data. A first identification unit for comparing and identifying, and a second identification unit for comparing and comparing a value converted into binary pseudo halftone density data using image data and a threshold value received from the control unit. And identification means.

The first discriminating means compares the image data and the background operation data, each of which has been converted into binary pseudo halftone density data, to convert the image data into binary pseudo halftone density data. If the data converted to the density data is larger, the area corresponding to the compared pseudo halftone density data is determined to be an "image", and the background calculation data is converted to binary pseudo halftone density data. If the converted data is larger, the area corresponding to the compared binary pseudo halftone density data may be determined to be “background”.

The second discriminating means compares the image data converted into binary pseudo halftone density data with a threshold value, and the binary pseudo halftone density data is larger. At this time, the area corresponding to the compared binary pseudo halftone density data is determined to be “image”, and when the threshold value is larger, the compared binary pseudo halftone density data is determined. Is preferably determined as the “background”.

[0011] Halftone calculation means for determining the degree of pseudo halftone of the binary background area data, and an image using binary image data and binary background calculation data obtained by the halftone calculation means. Two types of area identification means for identifying whether the area corresponding to the data and the background calculation data is an "image" or a "background"area; and either of the image data or the background calculation data when performing the image forming operation. Selecting means for selecting whether to output the image data, image position checking means for reading the image data from both the main scanning direction and the sub-scanning direction to check the image position, and an image forming range for determining the image forming range Determining means, and control means for controlling each means, wherein the selecting means includes image data, background calculation data, an identification result by two types of area identifying means, and an image forming range determining means. When the control unit receives a designation as to which one of the two types of area identification means to select, the area identified as “image” according to the specified area identification result is input. Outputs the image data, outputs the background calculation data to the area identified as "background" and determined to be within the image formation range by the image formation range determining means, and identifies the image as "background" and determines the image formation range. It is characterized in that the image data is output as it is to the area determined to be outside the image forming range by the means.

The image forming range determining means preferably compares the image position confirmed by the image position confirming means with the image forming range specified by the control means to determine the image forming range.

Halftone calculating means for determining the degree of pseudo halftone of the binary background area data, and second halftone calculating means for determining the degree of pseudo halftone of the binary image area data And using the image data and the binary background calculation data obtained by the halftone calculation means to determine whether the area corresponding to the image data and the background calculation data is “image” or “background”. And two types of area identification means for selecting which of the image data, the background calculation data and the image calculation data obtained by the second halftone calculation means to output when performing the image forming operation. Means, image position confirmation means for reading image data from both directions of the main scanning direction and sub-scanning direction to confirm the position of the image, image formation range determination means for determining the range in which the image is formed, Control means for controlling the stage, wherein the selection means includes image data, background calculation data, image calculation data, an identification result by the two types of area identification means, and an image formation range by the image formation range determination means. Is specified by the control means, which of the two types of area identification means is to be selected, and which of the three data inputted in the range for image formation is to be output. When the data is received, the output data is switched according to the range in which the image is formed.

[0014] The selecting means determines that the setting of the control means is "image gradation" and that the setting is "background gradation", the area identified as "image" according to the identification result by the area identifying means specified by the control means. The calculation data is output, and the background calculation data is output to the area identified as "background" and determined to be within the image formation range by the image formation range determination means. The image data may be output as it is to an area determined to be outside the image formation range.

The selection means outputs image operation data to an area identified as "image" according to the identification result of the area identification means specified by the control means that the setting of the control means is only "image gradation". It is preferable to output the image data as it is to the area identified as “background”.

The selection means outputs image data to an area identified as "image" according to the identification result of the area identification means specified by the control means that the setting of the control means is only "background gradation". Background calculation data is output to an area identified as "background" and determined to be within the image forming range by the image forming range determining unit, and is determined as "background" and determined to be outside the image forming range by the image forming range determining unit. It is preferable to output the image data as it is to the region.

[0017]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Next, an embodiment of an image forming apparatus according to the present invention will be described in detail with reference to the accompanying drawings. FIG.
5 to 5 show an embodiment of the image forming apparatus of the present invention.

The configuration and operation example of the first embodiment of the image forming apparatus of the present invention will be described in detail with reference to FIG. A in FIG.
FIG. 1 is a block diagram illustrating an overall configuration of a first embodiment of an image forming apparatus according to the present invention. FIG. 1B is a detailed block configuration diagram of an arithmetic unit 102 illustrated in FIG. FIG.
3C is a detailed block diagram of the area determination unit 103 shown in FIG. 1A.

As shown in FIG. 1A, a first embodiment of an image forming apparatus according to the present invention includes a CPU 101 for instructing each apparatus to set image formation, and a CPU C for instructing each apparatus to perform the following.
A computing unit 1 (102) for determining a degree of a binary pseudo halftone according to an instruction received from the PU 101, an area determining unit 1 (103) for performing two types of image area determination,
Using the input image data, the background operation data from the operation unit 1 (102), and the determination result from the area determination unit 1 (103), the selection unit 1 (which outputs edited image data according to the output image selection instruction received from the CPU 101) 104).

Arithmetic unit 1 (102) shown in FIG. 1B
Is a peripheral pixel storage unit 1 for storing a target pixel to be subjected to halftone processing and background area data of a predetermined number of pixels around the pixel to be processed.
(105) and a halftone calculation unit 1 (106) that determines a halftone density in accordance with a halftone instruction from the CPU 101 using the background area data accumulated by the peripheral pixel accumulation unit 1.
And a binarization circuit 107 for generating binary background operation data from the halftone density received from the halftone operation unit 1 (106) by using the systematic dither method, the error diffusion method, or the like. Is done. It should be noted that the background area data of a predetermined number of pixels around the pixel to be processed stored in the peripheral pixel storage unit 1 (105) is a binary halftone density in the halftone calculation unit 1 (106). This is the range of data required when generating.

The area determining unit 1 (10) shown in FIG.
3) a peripheral pixel storage unit 2 (108) that receives and accumulates image data of a pixel for which a region is to be determined and image data of a pixel around the target pixel, and a peripheral pixel storage unit 2 (10).
8) an adding unit 1 for adding the image data accumulated in step 8) and converting the added image data into a pseudo halftone density represented by binary data
(109), the peripheral pixel accumulation unit 3 (111) that receives and accumulates the background operation data of the pixel whose area is to be determined and the background operation data of the pixels around the pixel of interest, and the peripheral pixel accumulation unit 3 (111). An adder 2 (112) for adding the accumulated background calculation data to convert the data into pseudo halftone density data represented by binary data; and an adder 1 (10).
A mask unit 110 that compares the density of the pseudo halftone using the image data output from 9) with the density threshold value received from the CPU 101 to determine the image / background area;
The pseudo halftone density using the image data output from the adder 1 (109) is compared with the pseudo halftone density data using the background calculation data output from the adder 2 (112). Comparing section 113 for determining image / background area
And is configured. Note that the peripheral pixel storage unit 2 (10
8) and the range of the peripheral pixels stored in the peripheral pixel storage unit 3 (111) is an image of a range necessary when the adder unit 1 and the adder unit 2 detect binary pseudo halftone density data. Data and background calculation data.

Next, an operation example of the first embodiment of the present apparatus will be described. Image editing of the image forming apparatus according to the first embodiment is performed in the sub-scanning direction. The CPU 101 forms a pseudo halftone gradation image based on binary image data having a density gradient as shown in FIG. 4B with respect to the input image data shown in FIG. The background area data and the halftone instruction are issued for each sub-scanning line or for a plurality of sub-scanning lines. The background area data is image data that the CPU 101 has determined that many white images are background images when a document image is read. The halftone instruction is a set value of the halftone necessary when the binary background area data is added by the halftone calculation unit 1 (106) and the density of the halftone is calculated using the result.

The peripheral pixel accumulating unit 1 (105) accumulates background area data in a range necessary for calculating a halftone density in the halftone calculating unit 1 (106). Halftone calculation unit 106
First, the binary background area data accumulated in the peripheral pixel accumulation unit 1 (105) is added to detect a pseudo halftone density in the range. Then, the halftone density is calculated from the pseudo halftone density based on the halftone set value given by the halftone instruction from the CPU 101.

The binarization circuit 1 (107) binarizes the density of the halftone calculated by the halftone calculation unit 1 (106) by a systematic dither method, an error diffusion method, or the like, and determines the area as background calculation data. Unit 1 (103) and selection unit 1 (1
04) By using this background calculation data at the time of image formation, binary pseudo-halftone background data, that is, background gradation, can be formed on the image data.

In the peripheral pixel storage unit 2 (108) in the area determination unit 1 (103), the addition unit 1 (109) stores image data in a range necessary for determining the pseudo halftone density. In the peripheral pixel accumulation unit 3 (111), the addition unit 2
At (112), background calculation data in a range necessary for determining the density of the pseudo halftone is accumulated.

In the adder 1 (109), the peripheral pixel storage 2
The image data stored in (108) is added to detect a pseudo halftone density represented by binary data. The adder 3 (112) adds the background calculation data accumulated in the peripheral pixel accumulator 3 (111) to detect a pseudo halftone density represented by binary data.

The mask unit 110 compares the threshold value sent from the CPU 101 with the data obtained by converting the binary image data into pseudo halftone density by the adding unit 1 (109). When the density data of the pseudo halftone is larger than the threshold value, the range is determined to be “image”. When the threshold value is higher than the density of the pseudo halftone, the range is determined. The range is determined to be “background”.

The comparing unit 112 converts the binary image data into pseudo halftone density by the adding unit 109 and the binary background operation data into pseudo halftone density by the adding unit 112. Compare the data. If the density of the pseudo halftone is higher than that of the binary image data, it is determined that the compared range is "image". When the density of the pseudo halftone based on the binary background calculation data is larger, it is determined that the compared range is "background".

The comparison results from the mask unit 110 and the comparison unit 112 are sent to the selection unit 1 (104) as mask results and comparison results.

In the selecting section 1 (104), C is set before the copy operation.
An output image selection instruction is received from the PU 101. The output image selection instruction outputs the input image data as it is. According to the mask result, image data is output in a range determined as “image”, and background calculation data calculated by the calculation unit 102 is output in a range determined as “background”.
The input image data is output to the range determined as “image” according to the comparison result, and the background calculation data calculated by the calculation unit 102 is output to the range determined as “background”. It consists of the above three options.

The selecting unit 1 (104) selects the area determining unit 1 (10).
3) the mask result and comparison result, and the input image data
Input the background operation data from the operation unit 102 to the CP
Data is output according to an output image selection instruction from U101.

According to the above instruction, the selection unit 1 (10
3) When the data is output, the input image becomes the same as the input image shown in FIG. 4A. When the data is output in accordance with the instruction, the background gradation is obtained by the mask result as shown in FIG. , A background gradation based on the comparison result as shown in FIG.

Next, a second embodiment of the image forming apparatus of the present invention will be described with reference to FIG. The second embodiment of the image forming apparatus according to the present invention includes, in addition to the devices used in the first embodiment, a sub-scan for counting a line synchronization signal of input image data and confirming an image position in the sub-scan direction. Counter 202
A main scanning counter 203 that counts pixel synchronization signals of input image data to confirm an image position in the main scanning direction;
The image reading position from the sub-scanning counter 202 and the main scanning counter 203 and the designation of the range for image formation from the CPU 201 are input and the two ranges are compared.
And an area determination unit 2 (205) for checking whether the area is within the range specified by the above.

In the second embodiment, the selection unit 2 (204) includes the mask result and the comparison result from the area determination unit 1 (103), the input image data, the background calculation data from the calculation unit 1 (102), and The image forming range is input from the area determination unit 2, and the data is output by switching between the mask result and the comparison result according to the output image selection instruction from the CPU 201. Further, unlike the selection unit 1 of the first embodiment, the selection unit 2 of the second embodiment includes the selection unit 1 of the first embodiment within the image forming range determined by the area determination unit 2 (205). The same operation as described above is performed, but the image data corresponding to the range determined as being outside the image forming range by the area determination unit 2 (205) is output as it is. By the operation of the selection unit 2, it is possible to arbitrarily set the range for applying the background gradation.

In the first embodiment, only the background gradation shown in FIG. 5B is possible for the input image data shown in FIG. 5A. It is possible to arbitrarily set the image forming range by the operation of the unit 2 and perform the image forming with the background range arbitrarily set as shown in FIGS. 5 (c) and 5 (d). It becomes possible. FIG. 5C shows the gradation density changed from max to min (0) in a pseudo halftone in the range shown in the figure [main scanning direction a × sub-scanning direction b]. FIG. 5D shows the gradation result of FIG. 5B masked in the image setting range.

Next, a third embodiment of the image forming apparatus of the present invention will be described with reference to FIG. The third embodiment of the image forming apparatus according to the present invention includes, in addition to the devices used in the second embodiment, a peripheral pixel storage unit 4 (303) for receiving and storing image area data from input image data. Image area data accumulated by the pixel accumulation unit 4 and the CPU 301
A halftone calculation unit 2 (305) that determines a halftone density in response to a halftone instruction from the printer, and generates binary image calculation data from the halftone density received from the halftone calculation unit 2 (305). Arithmetic unit 2 including binarization circuit 2 (306)
(302). Further, the selection unit 3 (304) of the third embodiment differs from the selection unit 2 of the second embodiment in that the image calculation data from the calculation unit 2 is input in addition to the input image data, the background calculation data, the mask result, and the comparison result. Enter C
Data output is switched in accordance with an output image selection instruction from the PU 301 and the setting of the image forming range, image gradation, and background gradation from the area determination unit 2.

Next, the operation unit 2 which is a feature of the third embodiment
(302) and the operation of the selection unit 3 (304) will be described in detail. The peripheral pixel storage unit 4 receives and stores image area data in the input image data sent from the CPU 301. The range of the image area data stored in the peripheral pixel storage unit 4 is a range necessary for the halftone calculation unit 305 to calculate the binary pseudo halftone density. First, the halftone calculation unit 2 (305) detects binary pseudo halftone density by adding binary image area data in the accumulated range. Then, the CPU 3 determines the pseudo halftone density.
The density of the halftone is detected according to the halftone set value given from 01. The binarization circuit 2 (306) binarizes the halftone density data detected by the halftone calculation unit 2 (305) and converts it into binary image calculation data. By using this image operation data at the time of image formation, binary pseudo-halftone image data, that is, image gradation, can be formed on the image data.

The selection unit 3 (304) receives image operation data from the operation unit 2 in addition to the image data, the background operation data, the mask result, and the comparison result, and performs the same operation as the output image selection instruction of the first embodiment. Data output is switched according to the instruction, the image forming range setting, the image gradation, and the background gradation setting.

The input image data is output as it is as the operation pattern of the selector 3. According to the instruction of the image gradation and the background gradation, the image calculation data is output to the area determined to be “image”, and the background calculation data is output to the area determined to be “background” and determined to be within the image forming range. The input image data is output as it is to the area determined to be “background” and out of the image forming range. "Image" according to the instructions of the image gradation
The image calculation data is output to the area determined to be, and the input image data is output as it is to the area determined to be "background". In accordance with the instruction of the background gradation, image data is output to an area determined to be “image”, and background operation data is output to an area determined to be “background” and determined to be within the image forming range, and “background” is output. The input image data is output as it is to the area determined to be outside the image forming range. Since the above four operations are performed on both the mask result and the comparison result, there are a total of eight operation patterns.

When the selecting section 3 performs the operation, the input image data is formed as it is without performing any processing. When the operation is performed, gradation can be applied to both the image and the background area. By performing the operations (1), (2), it is possible to apply gradation only to the image, and by performing the operations further, it is possible to apply gradation only to the background.

The image forming apparatus of the first embodiment forms a density change (gradation) of the binary image data by pseudo halftone, and separates the image area and the background area from the input image data. It becomes possible to automatically form a background gradation.

In the image forming apparatus according to the second embodiment, in addition to the functions of the image forming apparatus according to the first embodiment, gradation processing can be performed in an arbitrary range in the main scanning direction and the sub-scanning direction. It becomes possible.

Further, in the image forming apparatus according to the third embodiment, in addition to the functions of the image forming apparatus according to the first embodiment or the second embodiment, a pseudo image area for input image data is provided. It is possible to perform gradation processing on an image by giving a density change due to a halftone.

[0044]

As is apparent from the above description, claim 1
To 4 form the density change (gradation) of the binary image data due to the pseudo halftone, and automatically form the background gradation by separating the image area and the background area from the input image data. It becomes possible.

Also, the provision of the two types of area determination means results in different determination results between the image area and the background area, and thus enables formation of different images.

According to the fifth and sixth aspects of the present invention, in addition to the functions of the above-described image forming apparatus, it is possible to perform gradation processing in an arbitrary range in the main scanning direction and the sub-scanning direction.

The image forming range determining means compares the image position with the image forming range designated by the control means to determine the image forming range, so that the image does not protrude from the image forming range and the image forming range is reduced. It can be set arbitrarily.

According to the image forming apparatus of the present invention, in addition to the function of the image forming apparatus described above, the image area of the input image data is given a density change by a pseudo half tone, thereby giving an image. A gradation process can be performed.

Further, the selection means switches the data output in accordance with the setting of the image gradation and the background gradation from the control means and the selection instruction of the mask result and the comparison result, whereby gradation processing can be performed on both image and background image areas. Become like

[Brief description of the drawings]

FIG. 1A is a block diagram illustrating a configuration of an image forming apparatus according to a first embodiment of the present invention, FIG. 1B is a block diagram illustrating a detailed configuration of a calculation unit, and C is a block illustrating a detailed configuration of an area determination unit. FIG.

FIG. 2 is a block diagram illustrating a configuration of an image forming apparatus according to a second embodiment of the present invention.

FIG. 3A is a block diagram illustrating a configuration of an image forming apparatus according to a third embodiment of the present invention, and FIG. 3B is a block diagram illustrating a detailed configuration of a calculation unit 2.

4A and 4B are diagrams illustrating a first example of background gradation, in which FIG. 4A illustrates an example of input image data, FIG. 4B illustrates a density gradient of the background gradation, and FIG. FIG. 7D is a diagram illustrating an example in which gradation is performed based on the result, and FIG. 7D is a diagram illustrating an example in which gradation is performed based on the comparison result.

5A and 5B are diagrams illustrating a second example of background gradation, in which FIG. 5A illustrates an example of input image data, FIG. 5B illustrates an example in which background gradation is applied to the entire surface, and FIG. ) Is a diagram showing an example of specifying an area to be subjected to background gradation, and (d)
FIG. 9 is a diagram illustrating a second example of an instruction for an area to be subjected to background gradation.

[Explanation of symbols]

 101 CPU 102 Operation unit 1 103 Area determination unit 1 104 Selection unit 1 105 Peripheral pixel accumulation unit 1 106 Halftone operation unit 1 107 Binarization circuit 1 108 Peripheral pixel accumulation unit 2 109 Addition unit 1 110 Mask unit 111 Peripheral pixel accumulation Section 3 112 addition section 2 113 comparison section 201 CPU 202 sub-scanning counter 203 main scanning counter 204 selection section 2 205 area determination section 2 301 CPU 302 calculation section 2 303 peripheral pixel accumulation section 4 304 selection section 3 305 halftone calculation section 2 306 Binarization circuit 2

Claims (10)

[Claims] 1. A halftone calculating means for determining a degree of pseudo halftone of binary background area data; and a binary image data and binary background calculating data obtained by the halftone calculating means. Two types of area identification means for identifying whether the area corresponding to the image data and the background calculation data is an “image” or a “background” area, and the image data when performing an image forming operation And selecting means for outputting which of the background calculation data, and control means for controlling each of the means. The selection means includes: the image data; the background calculation data; When the type of the identification result by the area identification means is input and the control means receives a designation of which of the two types of the area identification means to select, the designated area is selected. Another result identified regions "image" according to outputs the image data, the regions identified as "background" image forming apparatus and outputs the background operation data. 2. The area identification means receives the image data and the background calculation data, converts each of the data into binary pseudo-halftone density data, and converts the converted binary pseudo-halftone density data. First identification means for comparing and comparing tone density data with each other, and a threshold value received from the control means as a result of conversion into the binary pseudo halftone density data using the image data. 2. The image forming apparatus according to claim 1, further comprising: a second identification unit configured to identify the image forming apparatus by comparing with the image forming apparatus. 3. The image processing apparatus according to claim 1, wherein the first identification unit compares the image data and the background operation data obtained by converting each of the image data and the background calculation data into binary pseudo halftone density data, and converts the image data into the binary data. If the value converted to the pseudo halftone density data is larger, the area corresponding to the compared pseudo halftone density data is determined to be an "image", and the background calculation data is converted to the binary data. Wherein the area corresponding to the compared binary pseudo halftone density data is determined to be "background" when the data converted to the pseudo halftone density data is larger. 3. The image forming apparatus according to 2. 4. The image processing apparatus according to claim 1, wherein the second identification unit compares the threshold value with a value obtained by converting the image data into the binary pseudo-halftone density data, and compares the binary pseudo-halftone density data. When the tone data is larger, the corresponding area of the compared binary halftone density data is determined to be “image”, and when the threshold is larger, 3. The image forming apparatus according to claim 2, wherein a region corresponding to the binary pseudo halftone density data is determined as "background". 5. A halftone calculating means for determining a degree of pseudo halftone of binary background area data; and a binary image data and binary background calculating data obtained by said halftone calculating means. Two types of area identification means for identifying whether the area corresponding to the image data and the background calculation data is an “image” or a “background” area, and the image data when performing an image forming operation Selection means for selecting which of the data and the background calculation data to output; image position confirmation means for reading the image data from both the main scanning direction and the sub-scanning direction to confirm the image position; and forming an image. Image forming range determining means for determining a range to be performed; and control means for controlling each of the means. The selecting means includes the image data, the background calculation data, and the two types of areas. When the identification result by the identification unit and the image formation range by the image formation range determination unit are input, and the control unit receives a designation of which of the two types of the area identification units to select the identification result, The image data is output to an area identified as “image” according to the specified area identification result, and the area identified as “background” and determined to be within the image formation range by the image formation range determination unit is output as the image data. Output background calculation data,
An image forming apparatus characterized in that the image data is output as it is to an area identified as "background" and determined to be outside the image forming range by the image forming range determining means. 6. The image forming range determining unit determines that an image forming range is determined by comparing an image position confirmed by the image position confirming unit with an image forming range designated by the control unit. The image forming apparatus according to claim 5, wherein: 7. A halftone calculating means for determining a pseudo halftone level of binary background area data, and a second halftone determining a pseudo halftone level of binary image area data. Calculating means, and using the image data and the binary background calculating data obtained by the halftone calculating means, the area corresponding to the image data and the background calculating data is either "image" or "background" Two types of area identification means for identifying whether the data is data, and which of the image data, the background calculation data, and the image calculation data obtained by the second halftone calculation means when performing an image forming operation. Selecting means for selecting whether to output data; image position checking means for reading the image data in both the main scanning direction and the sub-scanning direction to check the position of the image; and a range for forming an image. An image forming range determining means for determining; and a control means for controlling each of the means. The selecting means includes: the image data, the background calculation data, the image calculation data, and the two types of area identification. Means for inputting the identification result by the means and the image formation range by the image formation range determining means, and the control means designates which of the two types of area identification means to select the identification result; An image forming apparatus characterized in that, upon receiving a setting of which of three data input to a range to be output, data to be output is switched according to a range to perform image formation. 8. The selection means is identified as “image” according to the identification result by the area identification means designated by the control means when the setting of the control means is “image gradation” and “background gradation”. The image calculation data is output to the area that has been identified, and the background calculation data is output to an area that is identified as “background” and that is determined to be within the image formation range by the image formation area determination unit. 8. The image forming apparatus according to claim 7, wherein the image data is output as it is to an area determined as being outside the image forming range by the image forming range determining unit. 9. The image processing apparatus according to claim 1, wherein the setting unit sets only the “image gradation” in the area identified as “image” according to the identification result of the area identifying unit specified by the control unit. The image forming apparatus according to claim 7, wherein operation data is output, and the image data is output as it is in an area identified as “background”. 10. The image processing apparatus according to claim 1, wherein the setting of the control means is only "background gradation", and the area identified as "image" according to the identification result of the area identification means specified by the control means. Output data,
The background calculation data is output to an area identified as "background" and determined to be within the image forming range by the image forming range determining unit, and the image forming range is identified as "background" and determined by the image forming range determining unit. The image forming apparatus according to claim 7, wherein the image data is output as it is to an area determined to be outside.