KR102712092B1 - Electronic device for image reduction and reduction method therefor - Google Patents

Abstract

An electronic device capable of reducing an image, comprising: a first image reduction unit which receives a second image and reduces the image size in a first direction, which is one of a horizontal direction and a vertical direction, to generate a third image; wherein the first image reduction unit calculates a first output active position value, determines a first output active position using the first output active position value, and generates pixels constituting the third image using pixel information of at least one of a pixel of the first output active position; and a pixel prior to the pixel of the first output active position; and the first output active position value.

Description

{ELECTRONIC DEVICE FOR IMAGE REDUCTION AND REDUCTION METHOD THEREFOR}

Embodiments disclosed herein relate to an electronic device capable of reducing an image and a method for reducing the image.

In computer graphics and digital imaging, image scaling refers to the resizing of digital images. Among them, scaling in the direction of image reduction is called downscaling. When downscaling the size of a raster graphic image, a new image with a smaller number of pixels than the original must be created. In this case, visible quality loss usually occurs.

From a digital signal processing perspective, scaling a raster graphic image is a two-dimensional example of sample rate conversion, which can be viewed as converting a discrete digital signal into another signal at a sampling rate that matches the sampling rate.

For the reduction of raster graphic images input in real time, the DDA (Digital Differential Analyzer) algorithm is very suitable. By calculating the increment by dividing the input image size by the output image size, and accumulating the increment for each output pixel, the location of the input pixel is acquired, which minimizes the use of multipliers and floating point operations that require a lot of hardware resources.

When using the DDA algorithm, an additional fractional bit is required as a resource for decimal operations in case the increment is not an integer multiple.

The purpose of the embodiments disclosed in this specification is to provide an electronic device and a reduction method thereof capable of reducing an image by applying a DDA algorithm with a small number of resources by compensating for an incremental accumulation value error due to a lack of decimal point bit resources during a decimal operation.

An electronic device capable of reducing an image comprises a first image reduction unit which receives a second image and reduces the image size in a first direction, which is one of a horizontal direction and a vertical direction, to generate a third image; wherein the first image reduction unit calculates a first output active position value, determines a first output active position using the first output active position value, and generates pixels constituting the third image using pixel information of at least one of a pixel of the first output active position; and a pixel prior to the pixel of the first output active position; and the first output active position value.

Specifically, the first output active position is position information of a pixel in the first direction among the second images, and the first output active position value is a value including: information for determining whether it is the first output active position; and incremental position information, which is position information between a pixel of the first output active position and a pixel preceding the pixel of the first output active position.

In addition, the first image reduction unit calculates a first difference value having a value corresponding to a value obtained by subtracting a product of a first increment, which is a candidate for an interval between one increment position and another increment position, and a size in the first direction of the third image from the size in the first direction of the second image; and a second difference value having a value corresponding to a value obtained by subtracting a size in the first direction of the second image from a product of a second increment, which is a candidate for an interval between one increment position and another increment position, and a size in the first direction of the third image.

The above first increment corresponds to a value obtained by dividing the size of the second image in the first direction by the size of the third image in the first direction, and the second increment corresponds to a value obtained by adding binary 1 to the bit corresponding to the lowest decimal place of the first increment.

In addition, each of the first increment and the second increment is a number having a decimal point of N bits, where N is an integer greater than or equal to 1.

Additionally, the first difference value corresponds to the number of incremental positions arranged at an interval of the second increment with respect to the size in the first direction of the second image, and the second difference value corresponds to the number of incremental positions arranged at an interval of the first increment with respect to the size in the first direction of the second image.

In addition, the first image reduction unit calculates a first incremental classification value for classifying the increment to which each pixel of the second image in the first direction belongs, as one of the first increment and the second increment. Furthermore, the first image reduction unit calculates the first incremental classification value at the position of the corresponding pixel by adding the second difference value to the first incremental classification value at the position of the corresponding pixel when the first incremental classification value at the position of the previous pixel of the second image in the first direction is negative, and by subtracting the first difference value from the first incremental classification value at the position of the corresponding pixel when the first incremental classification value at the position of the previous pixel of the second image in the first direction is not negative.

In addition, the first image reduction unit calculates the first output active position value at the position of the corresponding pixel in the first direction of the second image by adding a value of an increment classified by the first increment classification value to the first output active position value at the position of the previous pixel in the first direction of the second image if the position of the corresponding pixel in the first direction of the second image is the first output active position, and by subtracting 1 if the first output active position value at the position of the previous pixel is greater than 1.

The first image reduction unit determines the first output active position by using the integer part of the first output active position value at the position of the corresponding pixel. In addition, the first image reduction unit generates pixels constituting the third image by using the incremental position, which is the decimal part of the first output active position value.

According to an electronic device capable of reducing an image and a method for reducing the image, a DDA algorithm can be applied with fewer resources by compensating for an error in incremental accumulation due to a lack of decimal point bit resources during decimal part calculation.

FIG. 1 is a block diagram of an electronic device capable of reducing an image according to one embodiment.
Figure 2 is a diagram explaining the operation of the first image reduction unit when there is an integer increment.
Figure 3 is a diagram explaining the operation of the first image reduction unit in the case of a small number of increments.
Figure 4 is a configuration diagram of a first image reduction unit according to an embodiment.
Figure 5 is an explanatory diagram for the first difference value and the second difference value.

Hereinafter, an electronic device capable of reducing an image according to embodiments of the present disclosure and a reduction method thereof will be described in detail with reference to the attached drawings. It should be noted that the following embodiments of the present disclosure are intended only to concretize the present disclosure and do not limit or restrict the scope of the rights of the present disclosure. It is interpreted that what a specialist in the technical field to which the present disclosure belongs can easily infer from the detailed description and embodiments of the present disclosure falls within the scope of the rights of the present disclosure.

FIG. 1 illustrates a configuration diagram of an electronic device (100) capable of reducing an image according to one embodiment.

As can be seen from FIG. 1, an electronic device (100) capable of reducing an image according to an embodiment of the present invention comprises a first image blurring unit (10), a first image reduction unit (20), a second image blurring unit (30), a second image reduction unit (40), and an output selection unit (50).

Each of the first image blurring unit (10), the first image reduction unit (20), the second image blurring unit (30), the second image reduction unit (40), and the output selection unit (50) may be configured to include at least one of hardware consisting of a memory; and a logic circuit.

The first image blurring unit (10) receives a first image, blurs it in a first direction, either horizontal or vertical, through anti-aliasing processing, and outputs a second image. Here, the horizontal direction corresponds to the direction of the column of pixels constituting each image, i.e., the x-axis direction. In addition, the vertical direction corresponds to the direction of the row of pixels constituting each image, i.e., the y-axis direction.

When downscaling, the sampling rate of the output pixels is slower than the input, which causes signal distortion called aliasing. To minimize this problem, anti-aliasing is used to blur the image before downscaling. It can reduce the stair-stepping effect after image reduction through processing.

Anti-aliasing is applied by creating low pass filter coefficients using the Gaussian core of the following [Mathematical Formula 1].

In [Mathematical Formula 1], a represents a value in the first direction. That is, when the first direction is a horizontal direction, a represents a value in the x-axis, and when the first direction is a vertical direction, a represents a value in the y-axis.

In addition, σ is a coefficient that allows the degree of blurring, or blurring, of the image to be applied according to the downscaling ratio (ScaleRatio).

σ can be expressed as the following [Mathematical Formula 2].

In [Mathematical Formula 2], strn represents a coefficient that can adjust the degree of anti-aliasing according to the situation.

In digital images, a raster graphic image is characterized as a two-dimensional image with a width and height in pixel units through a square pixel grid. To reduce a raster graphic image, a decimation method can be used to acquire only the necessary pixels according to the reduction ratio.

The first image reduction unit (20) receives a second image, reduces the image size in the first direction, which is either the horizontal or vertical direction, and outputs a third image.

That is, the image size of the third image in the first direction is reduced from the image size of the second image in the first direction, but the image size of the third image in the second direction is maintained the same as the image size of the second image in the second direction. The second direction is the other direction among the horizontal direction and the vertical direction. If the first direction is the horizontal direction, the second direction becomes the vertical direction.

Specifically, the first image reduction unit (20) calculates a first output active position value and determines a first output active position using the first output active position value. In addition, the first image reduction unit (20) generates pixels constituting a third image using pixel information of at least one of a pixel of the first output active position; and a pixel before the pixel of the first output active position; and the first output active position value. The first image reduction unit (20) receives a second image in pixel units and calculates a first output active position value for each pixel.

The first output active position is position information of a pixel in the first direction among the second images used to generate pixels constituting the third image. In addition, the first output active position value is a value including: information for determining whether it is the first output active position; and incremental position information, which is position information between the pixel of the first output active position and the pixel preceding the pixel of the first output active position.

Figure 2 is a diagram explaining the operation of the first image reduction unit (20) in the case of having an integer increment.

Here, the increment refers to the change in the position of pixels in the second image for generating pixels constituting the third image. For example, when reducing an image from a second image of 300 pixels in the first direction to a third image of 150 pixels in the first direction, the increment is 2 pixels.

The first image reduction unit (20) can reduce the image size by a decimation method. However, the decimation method can only be applied when the ratio of the original image, the second image, and the reduced image, the third image, is an integer, so an additional response method is required for cases where the ratio of the original image and the reduced image is arbitrary.

Figure 3 is a diagram explaining the operation of the first image reduction unit (20) in the case of a small number of increments.

The first image reduction unit (20) is implemented so that the increment can be a decimal unit by providing a virtual decimal space to process the ratio of an arbitrary second image and a third image.

If the accumulated incremental position is a decimal point, the synthesis ratio between two adjacent pixels can be determined using the decimal point value. Here, the incremental position represents the position value of the corresponding second image when increasing in the first direction.

As shown in Fig. 3, since the increment is 1.5 pixels, pixels constituting the third image can be generated by synthesizing the left and right pixels of the corresponding incremental position in the second image at a ratio of 0.5.

However, in the first image reduction unit (20), the decimal point of the incremental position is set to have N bits in consideration of hardware resources. N is an integer greater than or equal to 1. Therefore, if the incremental position is not an integer position, a bilinear interpolation method can be used to weight and synthesize original pixel values on both sides according to the decimal point value. That is, if the bit value of the decimal point of the incremental accumulation position is 0001, the left pixel value and the right pixel value are synthesized at a ratio of 15:1.

For reference, the first image reduction unit (20) uses not only the position of the decimal increment, but also the first output active position, which is an integer corresponding to the increment position. If there is an increment position between the first pixel and the second pixel, the first output active position becomes the position of the second pixel on the right. However, the first image reduction unit (20) interpolates the first pixel and the second pixel by using the increment position, which is the value of the decimal part of the first output active position value, even if the position of the second pixel is the first output active position, to generate pixels constituting the third image.

Below, the first image reduction unit (20) will be described in detail.

Even if the increment is a decimal point, the size of the decimal point unit to create an increment that still satisfies all downscaling ratios is infinite, so it is impossible to implement it by simply adding decimal places. In the case of computer operations, floating point operations are sometimes used to implement high-precision operations by dividing them into fixed point parts and exponent parts, but floating point operations are not considered for efficient small hardware implementation.

Instead, the first image reduction unit (20) uses a technique for compensating for the inevitable incremental cumulative error in increments with limited decimal places. That is, in the first image reduction unit (20), the cumulative error that may occur when only the first increment is used can be compensated for by also using the second increment.

Figure 4 shows a configuration diagram of a first image reduction unit (20) according to one embodiment.

As can be seen from FIG. 4, the first image reduction unit (20) according to one embodiment is configured to include an increment and error calculator (21), a first incremental classification value calculator (22), a first output active position value calculator (23), and a third image generator (24).

The increment and error calculator (21) calculates a first increment, a second increment, a first difference value, and a second difference value.

The first increment and the second increment are candidates for the interval between one increment position and another increment position, respectively. That is, the interval between the increment positions of the second image is set to one of the first increment and the second increment.

In addition, each of the first increment and the second increment is a number having a decimal point of N bits, where N is an integer greater than or equal to 1. For example, when N is 4, each of the first increment and the second increment has a decimal point of 4 bits.

Specifically, the first increment corresponds to the value obtained by dividing the size of the second image in the first direction by the size of the third image in the first direction. When reducing an image from a second image of 300 pixels in the first direction to a third image of 120 pixels in the first direction, the first increment has a value of 2.5, which is (300/120). That is, if the integer part of the first increment is expressed in 4 bits, it becomes 0010, and if the decimal part of the first increment is expressed in 4 bits, it becomes 1000.

In addition, the second increment corresponds to the value obtained by adding binary 1 to the bit corresponding to the lowest decimal place of the first increment. That is, when reducing an image from a second image of 300 pixels in the first direction to a third image of 120 pixels in the first direction, if the integer part of the second increment is represented with 4 bits, it becomes 0010, the same as the integer part of the first increment, and if the decimal part of the second increment is represented with 4 bits, it becomes (1000+0001).

Figure 5 shows an explanatory diagram for the first difference value and the second difference value.

The first difference value is the accumulated error when increasing the first direction of the second image by the first increment. Specifically, the first difference value has a value corresponding to the value obtained by subtracting the product of the first increment and the first direction size of the third image from the size of the first direction of the second image.

In addition, the second difference value is an accumulated error when increasing the second image in the first direction by the second increment. Specifically, the second difference value has a value corresponding to the value obtained by subtracting the size of the second image in the first direction from the value obtained by multiplying the second increment by the size of the third image in the first direction.

That is, the first difference value (d1) and the second difference value (d2) can be expressed as in the following [Mathematical Formula 3] and [Mathematical Formula 4], respectively.

In [Mathematical Expressions 3] and [Mathematical Expressions 4], S2 represents the size of the second image in the first direction, S3 represents the size of the third image in the first direction, INC1 represents the first increment, and INC2 represents the second increment, respectively.

Combining [Mathematical Expression 3] and [Mathematical Expression 4], the second difference value (d2) can be expressed as in the following [Mathematical Expression 5].

Since the value of (INC2-INC1) is a binary number in which the value of the bit corresponding to the lowest decimal place among N bits is 1, the binary value of the second difference value (d2) is expressed as the value obtained by subtracting the first difference value (d1) from the value obtained by multiplying the size (S3) of the first direction of the third image by 1.

That is, the sum of the first difference value and the second difference value is equal to the size of the first direction of the third image.

That is, the first difference value corresponds to the number of incremental positions arranged at the interval of the second increment with respect to the size in the first direction of the second image. In addition, the second difference value corresponds to the number of incremental positions arranged at the interval of the first increment with respect to the size in the first direction of the second image.

In conclusion, if the second increment is appropriately distributed as many times as the first difference value, the final accumulated position of the increment can be set without cumulative error due to the increment.

If the ratio of the first increment and the second increment is arranged to match the second difference value and the first difference value, the second increments can be arranged as far apart as possible, which minimizes the unnaturalness caused by incremental compensation.

To implement this in hardware using a logic circuit, the first incremental classification value is set as a variable starting from 0.

That is, the first incremental classification value generator (22) calculates a first incremental classification value for classifying the increment to which each pixel in the first direction of the second image belongs, by one of the first increment and the second increment. In addition, the initial value of the first incremental classification value is set to 0.

The first incremental classification value needs to be updated at every increment.

Specifically, the first incremental classification value calculator (22) calculates the first incremental classification value at the position of the pixel by adding the second difference value to the first incremental classification value at the position of the previous pixel when the first incremental classification value at the position of the previous pixel in the first direction of the second image is negative, and by subtracting the first difference value from the first incremental classification value at the position of the previous pixel when the first incremental classification value at the position of the previous pixel in the first direction of the second image is not negative.

That is, if the first incremental classification value at the pixel is negative, the pixel belongs to the second increment, and if the first incremental classification value at the pixel is not negative, the pixel belongs to the first increment.

That is, the ratio at which the negative sign of the first incremental classification value; and 0 or positive sign; is set is the same as that of the first difference value and the second difference value.

Since the second image is based on the raster input unit, it is necessary to generate an output activation position indicating whether the downscaling result is valid for each pixel input. Since the output is activated once for each input number corresponding to the integer size that increases according to the incremental accumulation, the output activation position can be determined using the first output activation position value.

The first output active position value calculator (23) calculates the first output active position value.

The first output active position value is a variable whose initial value is 0. The first output active position value is a rational number having a range from a minimum of 0 to a maximum of the increment to which the corresponding pixel belongs. The integer part of the first output active position value can represent the number of pixels of the second image to be skipped during the increment, and the first output active position value calculator (23) determines the position of the next pixel in the second image as the first output active position when the first output active position value at the position of the corresponding pixel is less than 2. That is, the first output active position calculator (23) determines the first output active position using the integer part of the first output active position value at the position of the corresponding pixel, and the first output active position determined at this time can determine in advance the pixel corresponding to the first output active position from the previous pixel as the next pixel. That is, the integer part of the first output active position value at the position of the corresponding pixel is information for determining whether or not it is the first output active position.

The first output active position value can be updated for each input, and the increment determined according to the sign of the first increment classification value is added to the first output active position. In addition, regardless of whether the first output active position is present or not, if the first output active position value is greater than 1, 1 is subtracted from the value.

That is, the first output active position value calculator (23) calculates the first output active position value at the position of the corresponding pixel in the first direction of the second image by adding the value of the increment classified by the first increment classification value to the first output active position value at the position of the previous pixel in the first direction of the second image if the position of the corresponding pixel in the first direction of the second image is the first output active position, and by subtracting 1 if the first output active position value at the position of the previous pixel is greater than 1.

If the position of the corresponding pixel is the first output active position and is determined as the first increment, and the first output active position value at the position of the previous pixel is 1.5, the first output active position value at the corresponding pixel can be calculated as {1.5 + (first increment) - 1)}.

In addition, the third image generator (24) plays a role of generating a third image using the first output active position value.

Specifically, the third image generator (24) can generate pixels constituting the third image by using the incremental position, which is a decimal part of the first output active position value.

That is, the third image generator (24) interpolates the value of the pixel at the first output activation position and the value of the previous pixel in order to generate pixels constituting the third image. For example, if the value of the decimal part of the first output activation position value is 0, the third image generator (24) outputs the pixel at the first output activation position as is, and if the value of the decimal part of the first output activation position value is 0001, the value of the previous pixel and the value of the pixel at the first output activation position are synthesized at a ratio of 15:1 to generate pixels constituting the third image.

If there is a decimal part value of the first output active position value, the two pixels can be synthesized in that ratio to reduce the staircase phenomenon of the reduced image. If the first output active position value has a decimal point of 4 bits, the synthesis ratio is from 15:1 to 0:16.

The second image blurring unit (30) receives a third image, blurs it in the second direction, which is the other direction among the horizontal and vertical directions, by anti-aliasing processing, and outputs a fourth image.

If the first direction of the first image blur (10) is a horizontal direction, the second direction of the second image blur (30) is a vertical direction. The operation of the second image blur (30) is the same as that of the first image blur (10) except that the direction is different, so a separate detailed description will be omitted.

The second image reduction unit (40) receives the fourth image, reduces the image size in the second direction, which is the other direction among the horizontal and vertical directions, and outputs the fifth image. The second image reduction unit (40) reduces the image in a different direction from the first image reduction unit (20), but its operation is the same as that of the first image reduction unit (20), so a separate detailed description will be omitted.

The output selection unit (50) selects and outputs one image among the first image, the third image, and the fifth image.

Hereinafter, an image reduction method according to an embodiment will be described. Since the image reduction method according to an embodiment is implemented by the electronic device (100) capable of reducing the image described above, it is obvious that it includes all the features of the electronic device (100) capable of reducing the image even without a separate description.

An image reduction method according to an embodiment comprises a first image blurring step (S10), a first image reduction step (S20), a second image blurring step (S30), a second image reduction step (S40), and an output selection step (S50).

In the first image blurring step (S10), a first image is input and blurred in a first direction, either a horizontal or vertical direction, through anti-aliasing processing, to output a second image.

In the first image reduction step (S20), the second image is input and the image size in the first direction, either the horizontal or vertical direction, is reduced to output the third image. Here, the horizontal direction corresponds to the direction of the column of pixels constituting each image, i.e., the x-axis direction. In addition, the vertical direction corresponds to the direction of the row of pixels constituting each image, i.e., the y-axis direction.

Specifically, in the first image reduction step (S20), the first output active position value is calculated, and the first output active position is determined using the first output active position value. In addition, the first image reduction step (S20) generates pixels constituting the third image using pixel information of at least one of a pixel of the first output active position; and a pixel before the pixel of the first output active position; and the first output active position value.

The first output active position is position information of a pixel in the first direction among the second images used to generate pixels constituting the third image. In addition, the first output active position value is a value including: information for determining whether it is the first output active position; and incremental position information, which is position information between the pixel of the first output active position and the pixel preceding the pixel of the first output active position.

Specifically, the first image reduction step (S20) includes a step (S21) of calculating a first increment which is a candidate for the interval between one increment position and another increment position; a step (S22) of calculating a second increment which is a candidate for the interval between one increment position and another increment position; a step (S23) of calculating a first difference value having a value corresponding to a value obtained by subtracting a value obtained by multiplying the first increment by the size in the first direction of the third image from a size in the first direction of the second image; and a step (S24) of calculating a second difference value having a value corresponding to a value obtained by subtracting a value obtained by multiplying the second increment by the size in the first direction of the third image.

The first increment is equal to the size of the second image in the first direction divided by the size of the third image in the first direction.

In addition, the first difference value corresponds to the number of incremental positions arranged at the interval of the second increment with respect to the size in the first direction of the second image. In addition, the second difference value corresponds to the number of incremental positions arranged at the interval of the first increment with respect to the size in the first direction of the second image.

The first increment and the second increment are each numbers with N decimal places, where N is an integer greater than or equal to 1.

Additionally, the second increment corresponds to the bit corresponding to the lowest decimal place of the first increment plus binary 1.

In addition, the first image reduction step (S20) further includes a step (S25) of calculating a first increment classification value for classifying an increment to which each pixel in the first direction of the second image belongs, as one of the first increment and the second increment; a step (S26) of calculating a first output active position value; and a step (S27) of determining a first output active position using the value of the integer part of the first output active position value at the position of the corresponding pixel; and a step (S28) of generating pixels constituting a third image using the value of the decimal part of the first output active position value.

Specifically, in the step (S25) of calculating the first incremental classification value, if the first incremental classification value at the position of the previous pixel in the first direction of the second image is negative, the second difference value is added to the first incremental classification value at the position of the previous pixel, and if the first incremental classification value at the position of the previous pixel in the first direction of the second image is not negative, the first difference value is subtracted from the first incremental classification value at the position of the previous pixel, thereby calculating the first incremental classification value at the position of the corresponding pixel.

In addition, in the step (S26) of calculating the first output active position value, if the position of the corresponding pixel in the first direction of the second image is the first output active position, the value of the increment classified by the first increment classification value is added to the first output active position value at the position of the previous pixel in the first direction of the second image, and if the first output active position value at the position of the previous pixel is greater than 1, 1 is subtracted, thereby calculating the first output active position value at the position of the corresponding pixel.

In the step (S27) of determining the first output active position, if the first output active position value at the position of the corresponding pixel is less than 2, the position at the next pixel in the second image is determined as the first output active position.

In the second image blurring step (S30), a third image is input and blurred in a second direction, which is the other direction among the horizontal and vertical directions, by anti-aliasing processing, and a fourth image is output. In addition, in the second image reduction step (S40), a fourth image is input and the image size in the second direction, which is the other direction among the horizontal and vertical directions, is reduced to output a fifth image.

In the output selection step (S50), one image among the first image, the third image, and the fifth image is selected and output.

According to the electronic device (100) capable of reducing an image as described above and the reduction method thereof, it can be seen that the DDA algorithm can be applied with fewer resources by performing compensation for an incremental accumulation value error due to a lack of decimal point bit resources during decimal part calculation.

100 : Electronic Devices
10: Blur of the first image
20: First image reduction section
30: Second image blur
40: Second image reduction section
50 : Output selection section
21: Increment and error calculator
22: First incremental classification value generator
23: 1st output active position value generator
24: Third Image Generator

Claims (16)

In an electronic device capable of reducing an image,
A first image reduction unit that receives a second image and reduces the image size in one of the horizontal and vertical directions to generate a third image;
The first image reduction unit calculates a first output active position value, determines a first output active position using the first output active position value, and generates pixels constituting the third image using pixel information of at least one of a pixel of the first output active position; and a pixel preceding the pixel of the first output active position; and the first output active position value.
The above first output active position is the position information of the pixel in the first direction among the second images,
The above first output active position value is a value including information for determining whether the first output active position is present; and incremental position information, which is position information between a pixel of the first output active position and a pixel preceding the pixel of the first output active position;
The first image reduction unit further calculates a first difference value having a value corresponding to a value obtained by subtracting a product of a first increment, which is a candidate for an interval between one increment position and another increment position, and a size in the first direction of the third image from a size in the first direction of the second image; a second difference value having a value corresponding to a value obtained by subtracting a size in the first direction of the second image from a product of a second increment, which is a candidate for an interval between one increment position and another increment position, and a size in the first direction of the third image; and a first increment classification value for classifying an increment to which each pixel in the first direction of the second image belongs, as one of the first increment and the second increment,
The first image reduction unit calculates the first incremental classification value at the position of the pixel by adding the second difference value to the first incremental classification value at the position of the previous pixel when the first incremental classification value at the position of the previous pixel in the first direction of the second image is negative, and by subtracting the first difference value from the first incremental classification value at the position of the previous pixel when the first incremental classification value at the position of the previous pixel in the first direction of the second image is not negative.
The first image reduction unit calculates a first output active position value at the position of the corresponding pixel by using the value of the increment classified by the first increment classification value,
The above first increment corresponds to a value obtained by dividing the size of the second image in the first direction by the size of the third image in the first direction.
The above second increment corresponds to the value obtained by adding binary 1 to the bit corresponding to the lowest decimal place of the above first increment,
Each of the above first increment and the above second increment is a number having a decimal point of N bits,
The above first difference value corresponds to the number of incremental positions arranged at the interval of the second increment with respect to the size of the first direction in the second image,
The second difference value corresponds to the number of incremental positions arranged at intervals of the first increment with respect to the size of the first direction in the second image,
An electronic device, wherein N is an integer greater than or equal to 1. delete delete delete delete In the first paragraph,
The above first image reduction unit, at the position of the previous pixel in the first direction of the second image, the first output active position value,
An electronic device that calculates a first output active position value at a position of a corresponding pixel by adding a value of an increment classified by the first incremental classification value when the position of the corresponding pixel in the first direction of the second image is the first output active position, and subtracting 1 when the first output active position value at the position of the previous pixel is greater than 1. In the first paragraph,
The above first image reduction section,
An electronic device that determines the first output active position by using the integer part of the first output active position value at the position of the corresponding pixel. In the first paragraph,
The first image reduction section above,
An electronic device that generates pixels constituting the third image by using the incremental position, which is a value of a decimal part of the first output active position value. In the image reduction method,
A first image reduction step for receiving a second image and reducing the size of the image in one of the horizontal and vertical directions to generate a third image; including:
In the first image reduction step, a first output active position value is calculated, a first output active position is determined using the first output active position value, and pixels constituting the third image are generated using pixel information of at least one of a pixel of the first output active position; and a pixel before the pixel of the first output active position; and the first output active position value.
The above first output active position is the position information of the pixel in the first direction among the second images,
The above first output active position value is a value including information for determining whether the first output active position is present; and incremental position information, which is position information between a pixel of the first output active position and a pixel preceding the pixel of the first output active position;
The first image reduction step comprises: a step of calculating a first difference value having a value corresponding to a value obtained by subtracting a product of a first increment, which is a candidate for an interval between one increment position and another increment position, and a size in the first direction of the third image from a size in the first direction of the second image; a step of calculating a second difference value having a value corresponding to a value obtained by subtracting a size in the first direction of the second image from a product of a second increment, which is a candidate for an interval between one increment position and another increment position, and a size in the first direction of the third image; a step of calculating a first increment classification value for classifying an increment to which each pixel in the first direction of the second image belongs, as one of the first increment and the second increment; and a step of calculating the first output active position value;
In the step of calculating the first incremental classification value, if the first incremental classification value at the position of the previous pixel in the first direction of the second image is negative, the second difference value is added to the first incremental classification value at the position of the previous pixel, and if the first incremental classification value at the position of the previous pixel in the first direction of the second image is not negative, the first difference value is subtracted from the first incremental classification value at the position of the previous pixel, thereby calculating the first incremental classification value at the position of the corresponding pixel.
In the step of calculating the first output active position value, the first output active position value at the position of the corresponding pixel is calculated using the value of the increment classified by the first increment classification value,
The above first increment corresponds to a value obtained by dividing the size of the second image in the first direction by the size of the third image in the first direction.
The above second increment corresponds to the value obtained by adding binary 1 to the bit corresponding to the lowest decimal place of the above first increment,
Each of the above first increment and the above second increment is a number having a decimal point of N bits,
The above first difference value corresponds to the number of incremental positions arranged at the interval of the second increment with respect to the size of the first direction in the second image,
The second difference value corresponds to the number of incremental positions arranged at intervals of the first increment with respect to the size of the first direction in the second image,
An image reduction method, wherein N is an integer greater than or equal to 1. delete delete delete delete In Article 9,
In the step of calculating the first output active position value, the first output active position value at the position of the previous pixel in the first direction of the second image,
An image reduction method, wherein the first output active position value at the position of the corresponding pixel in the first direction of the second image is calculated by adding the value of the increment classified by the first increment classification value if the position is the first output active position, and subtracting 1 if the first output active position value at the position of the previous pixel is greater than 1. In Article 9,
The above first image reduction step is,
An image reduction method, comprising: a step of determining the first output active position by using the integer part of the first output active position value at the position of the corresponding pixel. In Article 9,
The first image reduction step is as follows:
An image reduction method, comprising: a step of generating pixels constituting the third image by using the incremental position, which is a value of a decimal part of the first output active position value;

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