A method for contrast of very large images

Abstract

The embodiment of the application discloses a super large image contrast method, comprising the following steps: step 1, defining that the first image and the second image each comprise M rows and N columns of pixels, the size of each pixel is 1 bit, and the storage space of the third image is M rows and N columns of storage squares; step 2, dividing the first image into K first sub-images in left-to-right or right-to-left order, each first sub-image comprising M rows and L columns of pixels, wherein N=K*L, and dividing the second image into K second sub-images in the same division order as the first image; step 3, sequentially comparing the K first sub-images of the first image with the K second sub-images of the second image one by one to obtain K third sub-images, and sequentially placing the K third sub-images into the storage space of the third image, and the K third sub-images are spliced into a third image. The third image can quickly and intuitively observe the similarities and differences between two binary images with the same number of rows and columns.

Description

Technical Field

[0001] The invention belongs to the field of image processing, and in particular relates to a method for comparing pixels of an ultra-large image. Background Art

[0002] In the field of laser direct writing, processing large images requires extensive memory. For example, comparing two binary images, each with a pixel size of 160,000 x 260,000, is crucial. In some implementations, the two binary images are typically compared pixel by pixel, at the same position within the same row and column. This computationally intensive and inefficient comparison method requires significant memory resources and can even cause program crashes. Summary of the Invention

[0003] The present invention provides a method for comparing pixels of an ultra-large image, which aims to solve the problems of large computational complexity and low efficiency in the existing method for comparing pixels of an ultra-large image.

[0004] The scheme of the present invention is as follows:

[0005] Step 1: Define the first image and the second image to consist of M rows × N columns of pixels, with each pixel being 1 bit in size, and define the storage space of the third image to be M rows × N columns of storage grids;

[0006] Step 2: Divide the first image into K first sub-images in a left-to-right or right-to-left order, where each first sub-image includes M rows × L columns of pixels, where N = K × L. Divide the second image into K second sub-images in the same division order as the first image.

[0007] Step 3: Compare the K first sub-images of the first image with the K second sub-images of the second image one by one in sequence to obtain K third sub-images, and sequentially store the K third sub-images into the storage space of the third image, and stitch the K third sub-images into a third image;

[0008] In the first image and the second image, the number 0 represents a white pixel, and the number 1 represents a black pixel; in the third image, the size of each pixel is 2 bits, and the pixel color is at least black or white, the number 00 represents a white pixel, and the number 11 represents a black pixel.

[0009] In some embodiments, K first sub-images of the first image are sequentially compared with K second sub-images of the second image one by one to obtain K third sub-images, specifically including:

[0010] Step 31: Compare any first sub-image among the K first sub-images of the first image with the corresponding second sub-image of the second image to obtain a third sub-image;

[0011] Step 32: Using the same approach as step 31, the remaining (K-1) first sub-images are compared one by one with the corresponding (K-1) second sub-images to obtain (K-1) third sub-images.

[0012] In some embodiments, step 31 includes:

[0013] Step 311: If L pixels of a first image strip in one row of any first sub-image are completely identical to L pixels of a second image strip in a corresponding row of the corresponding second sub-image after a one-to-one comparison, then the third image strip displayed in that row of the third sub-image is identical to the first image strip or the second image strip;

[0014] Step 312: If the L pixels of a first image strip in one row of any first sub-image are not completely consistent with the L pixels of a second image strip in a corresponding row of the corresponding second sub-image after a one-to-one comparison, proceed as follows:

[0015] Step 312A: Perform a bitwise AND operation on the L strings of numbers including 0 and / or 1 in the L pixels of a first image strip in one row of any first sub-image and the L strings of numbers including 0 and / or 1 in the L pixels of a second image strip in a corresponding row of the second sub-image, to obtain L common bits including 0 and / or 1.

[0016] Step 312B: If there is at least one digit 1 in the common bits, then the corresponding pixel of the third image strip in the corresponding row of the third sub-image corresponding to each digit 1 is a black pixel, and the byte of the black pixel is defined as a 2-bit digit string 11;

[0017] Step 312C: If there is at least one digit 0 in the common digits, perform the following operations:

[0018] Step 312C1: If the number of the corresponding pixel in the first image strip of the corresponding row of the first sub-image corresponding to the number 0 in the shared bit is ORed with the corresponding number 0 in the shared bit, and the result of the OR operation is 0, and the number of the corresponding pixel in the second image strip of the corresponding row of the second sub-image corresponding to the number 0 in the shared bit is ORed with the number 0 in the shared bit, then the corresponding pixel in the third image strip of the corresponding row of the third sub-image is a white pixel, and the size of the white pixel is 2 bits, represented by the digital string 00;

[0019] Step 312C2: If the result of an OR operation between the corresponding pixels of the corresponding row and the corresponding first image strip of the first sub-image corresponding to the number 0 in the shared bit and the number 0 in the shared bit is 1, and the result of an OR operation between the corresponding pixels of the corresponding row and the second image strip of the second sub-image corresponding to the number 0 in the shared bit and the number 0 in the shared bit is 0, then the corresponding pixels of the corresponding row and the third image strip of the corresponding third sub-image are first color pixels other than white pixels and black pixels, and the size of the first color pixel is 2 bits, represented by the digital string 10;

[0020] Step 312C3: If the corresponding pixels of the first image strip of the corresponding row of the first sub-image corresponding to the number 0 in the common bit are ORed with the number 0 in the common bit, and the result is 0, and the corresponding pixels of the second image strip of the corresponding row of the second sub-image corresponding to the number 0 in the common bit are ORed with the number 0 in the common bit, and the result is 1, then the corresponding pixels of the third image strip of the corresponding row of the corresponding third sub-image are second color pixels other than white pixels, black pixels, and first color pixels, and the size of the second color pixel is 2 bits, represented by the string 01.

[0021] Therein, the order of steps 31 to 33 is not particular; the order of steps 33C1 to 33C3 is not particular.

[0022] In some embodiments, the first color is red and the second color is blue.

[0023] Beneficial technical effects of the present invention: This application compares two binary images with the same number of rows and columns, and obtains a third image based on the comparison results. Since the number of rows and columns of the third image is the same as those of the two binary images, the similarities and differences between the two binary images with the same number of rows and columns can be quickly and intuitively judged based on the third image. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] Figure 1 A diagram showing the steps of a method according to an embodiment of the present invention;

[0025] Figure 2 A schematic diagram showing a third image having 11 rows × 128 columns of pixels obtained by comparing an exemplary first image having 11 rows × 128 columns of pixels with an exemplary second image having 11 rows × 128 columns of pixels and displaying the comparison result in pixel form;

[0026] Figure 3 A schematic diagram showing a comparison of an exemplary 64 pixels of a first sub-image strip in a first row of a first sub-image and an exemplary 64 pixels of a second sub-image strip in a first row of a first sub-image after being expressed numerically;

[0027] Figure 4 A schematic diagram showing a comparison of an exemplary 64 pixels of a first sub-image strip in the third row of a first sub-image and an exemplary 64 pixels of a second sub-image strip in the third row of a first second sub-image after being expressed numerically;

[0028] Figure 5 Schematic diagram showing comparison of exemplary 64 pixels of the fifth row of the first sub-image strip of the first first sub-image and exemplary 64 pixels of the fifth row of the second sub-image strip of the first second sub-image after being expressed numerically. DETAILED DESCRIPTION

[0029] The following will clearly and completely describe the technical solutions in the embodiments of the present invention in conjunction with the accompanying drawings. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative efforts are within the scope of protection of the present invention.

[0030] In the description of the present invention, it should be noted that the terms "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inside", "outside" and the like, indicating directions or positional relationships, are based on the directions or positional relationships shown in the accompanying drawings and are only for the convenience of describing the present invention and simplifying the description. They do not indicate or imply that the devices or components referred to must have a specific direction, be constructed and operated in a specific direction, and therefore should not be understood as limiting the present invention. The terms "first", "second", and "third" are only used to describe the difference and should not be understood as indicating or implying relative importance. In addition, unless otherwise expressly specified and limited, the terms "installed", "connected", and "connected" should be understood in a broad sense. For example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection, an indirect connection through an intermediate object, or the internal connection of two components. For those skilled in the art, the specific meanings of the above terms in the present invention can be understood according to the specific circumstances.

[0031] refer to Figure 1 , an ultra-large image comparison method disclosed in an embodiment of the present application includes:

[0032] Step 1: Define the first image and the second image to consist of M rows × N columns of pixels, with each pixel being 1 bit in size, and define the storage space of the third image to be M rows × N columns of storage grids;

[0033] Step 2: Divide the first image into K first sub-images in a left-to-right or right-to-left order, where each first sub-image includes M rows × L columns of pixels, where N = K × L. Divide the second image into K second sub-images in the same division order as the first image.

[0034] Step 3: Compare the K first sub-images of the first image with the K second sub-images of the second image one by one in sequence to obtain K third sub-images, and sequentially store the K third sub-images into the storage space of the third image, and stitch the K third sub-images into a third image;

[0035] In the first image and the second image, the number 0 represents a white pixel, and the number 1 represents a black pixel; in the third image, the size of each pixel is 2 bits, and the pixel color is at least black or white, the number 00 represents a white pixel, and the number 11 represents a black pixel.

[0036] The first image and the second image are both binary images.

[0037] The following combination Figures 2 to 5 , describe steps 1 to 3 in detail.

[0038] Will Figure 2 The leftmost image is defined as the first image, the middle image is defined as the second image, and the rightmost image is defined as the third image. The first and second images both contain M rows × N columns of pixels and are binary images. Exemplarily, M is 11, N is 128, and the size of each pixel in the first and second images is defined as 1 bit. The storage space for the third image is defined as 11 rows × 128 columns of storage grids, and each storage grid can store a pixel of 2 bits.

[0039] Since N is exemplarily 128 in both the first and second images, the first image is divided into two first sub-images from left to right, each of which includes 11 rows x 64 columns of pixels, i.e., K = 2. It should be noted that the 64 columns in each sub-image is also exemplary; the number of columns in the two first sub-images can be the same or different. For ease of description, this application represents both first sub-images as having 64 columns. Each row of the two first sub-images is defined as a first image strip. Similarly, dividing the second image into two second sub-images from left to right, each of which includes 11 rows x 64 columns of pixels, is also merely exemplary. Each second sub-image has the same number of rows and columns as the corresponding first sub-image: for example, the first second sub-image has the same number of rows and columns as the corresponding first first sub-image; the second second sub-image has the same number of rows and columns as the corresponding second first sub-image. Each row of the two second sub-images is defined as a second image strip.

[0040] Will Figure 2 Each row of the first image strip of the first first sub-image is compared as a whole with each row of the second image strip corresponding to the first second sub-image, and the comparison result is displayed in the form of pixels at the corresponding row position in the first third sub-image of the third image, and the obtained rows of third image strips are sequentially composed of the first third sub-image.

[0041] Similarly, Figure 2 Each row of the first image strip of the second first sub-image is compared with each corresponding row of the second image strip of the second second sub-image, and the comparison result is displayed in the form of pixels at the corresponding position in the second third sub-image of the third image. The obtained rows of third image strips sequentially constitute the second third sub-image. The first third sub-image and the second third sub-image are spliced ​​end to end according to the third image strips in the same row, and finally constitute the third image. Since the first image and the second image are binary images, the pixels of the third image contain at least two types of pixels, black or white, but each byte of these two pixels is 2 bits. For example: if the first image is all white pixels and the second image is also all white pixels, then the pixels of the output third image are all white pixels; if the first image is all black pixels and the second image is also all black pixels, then the pixels of the output third image are also all black pixels.

[0042] Figure 2In the embodiment of the present invention, any row of the first image strip of any (i.e., the first or the second) first sub-image is compared as a whole with the row of the second image strip of the corresponding second sub-image, and the comparison result is displayed in the form of a third image strip at the corresponding position of the corresponding third sub-image. The result of the overall comparison may be completely identical or partially identical, and the two different results are processed in different ways. It should be noted that the two rows of corresponding first image strips and second image strips mentioned in this application are completely identical, which means that each pixel of the first image strip is compared one by one with each pixel of the corresponding second image strip, and they are completely identical. This does not mean that each pixel of the first image strip or the second image strip is required to be the same, for example, it is not required that all pixels of the first image strip are white pixels or all black pixels.

[0043] The following examples illustrate this:

[0044] (1) The size of each pixel in the first and second images is 1 bit, and both the first and second images are binary images. Therefore, in the first and second images, 0 represents a white pixel and 1 represents a black pixel. In each sub-image of the third image, the size of each pixel is 2 bits, and the digital string 00 is defined to represent a white pixel. Please refer to Figure 2 and Figure 3 The exemplary 64 pixels in the first row and first image strip L1111 (1 row × 64 columns) of the first first sub-image are all white pixels, represented by 000.......000 (64 bits total). The corresponding exemplary 64 pixels in the first row and second image strip L1212 (1 row × 64 columns) of the first second sub-image are also all white pixels, represented by 000.......000 (64 bits total). That is, a one-to-one comparison of each pixel in the two is exactly the same. Therefore, since the two are exactly the same, after comparing them, the output result is represented by the first row and third image strip of the first third sub-image, consisting of 64 white pixels, represented by 000000......000000 (128 bits total). That is, a two-bit digit string 00 represents a white pixel.

[0045] (2). Please continue to refer to Figure 2 and Figure 4 , the exemplary 64 pixels in the third row of the first image strip (3 rows × 64 columns) of the first first sub-image are not all white pixels: the pixels in the 62nd column are black pixels. The 64 pixels in the third row of the second image strip (3 rows × 64 columns) of the first second sub-image are all white pixels. Therefore, the third row of the first image strip of the first first sub-image and the third row of the second image strip of the first second sub-image are not identical.

[0046] The third row of the first image strip of the first sub-image is represented by L1131, and the corresponding pixels are represented by the digital string: 000...100, totaling 64 bits. The third row of the second image strip of the first sub-image is represented by L1232, and the corresponding pixels are represented by the digital string: 000...000, totaling 64 bits.

[0047] Since the third row of the first image strip of the first sub-image and the third row of the second image strip of the first second sub-image are not exactly the same, the following operations need to be performed:

[0048] Perform a bitwise AND operation on each corresponding digit of the digital string 000...100 (64 bits total) corresponding to the first image strip in the third row of the first sub-image and the digital string 000...000 (64 bits total) corresponding to the second image strip in the third row of the first second sub-image (i.e., if either digit is 0, the result is 0). The result is represented by the common digital string common1: 000...000, totaling 64 bits. Since there is a 0 in the common bits, the following operations need to be performed:

[0049] Perform an OR operation on the digital string corresponding to the third row of the first sub-image, L1131, with each digit corresponding to the common digital string common1 (if the two digits are the same, the result is 0; if the two digits are different, the result is 1), to obtain the first unique bit, represented by unique11: 000...100, a total of 64 bits; perform an OR operation on the digital string corresponding to the third row of the second sub-image, L1131, with the common digital string common1, to obtain the second unique bit, represented by unique21: 000...000, a total of 64 bits. Compare the first unique bit 000...100 with the second unique bit 000...000 one by one, and obtain 128 output digital strings including the digits 0 or 1, and obtain the comparison result result1, represented by 128 bits, see Figure 4 For example, the first digit 0 from the left of the first unique bit unique11 is compared with the first digit 0 from the left of the second unique bit unique21. The result is represented by 00, and the pixel displayed is a white pixel. That is, the first pixel from the left of the third image strip in the third row of the third sub-image of the first frame is a white pixel. Figure 2As shown. Compare the second digit 0 from the left of the first unique bit unique12 with the second digit 0 from the left of the second unique bit unique22, and the result is represented by 00. The pixel displayed is a white pixel, that is, the second pixel from the left of the third image strip of the third row of the first third sub-image is a white pixel. Compare the 62nd digit 1 from the left of the first unique bit unique12 with the 62nd digit 0 from the left of the second unique bit unique21, and the result is represented by 10. The pixel displayed is a first color other than black and white, that is, the color of the 62nd pixel from the left of the third image strip of the third row of the first third sub-image is the first color. Taking into account the limitations of the color submission of the drawings in the patent application specification, the first color is Figure 2 The plurality of horizontal dotted lines shown are schematically represented. In some embodiments, the first color can be red, purple or cyan. It can be seen that any pixel in any row of the third image strip of the first third sub-image occupies 2 bits.

[0050] (3).Reference Figure 2 and Figure 5 , let's take another example Figure 2 Compare the results of the fifth row of the first image strip of the first sub-image and the fifth row of the second image strip of the first second sub-image. The fifth row of the first image strip of the first sub-image is represented by L1151; the fifth row of the second image strip of the first second sub-image is represented by L1252. L1151 is represented by 001...100, a total of 64 bits; L1252 is represented by 011...111, a total of 64 bits. Since L1151 and L1252 are not exactly the same, further comparison is required:

[0051] First, a bitwise AND operation is performed on the number string 001...100 (64 bits in total) corresponding to the first image strip of the fifth row of the first sub-image of the first frame and the number 011...111 (64 bits in total) corresponding to the second image strip of the fifth row of the first second sub-image of the first frame (that is, as long as one of the two numbers is 0, the calculation result is 0). The calculation result is represented by the common number string common2, and the result is expressed as 001...100, with a total of 64 bits.

[0052] After obtaining the common numeric string common2, since the number 0 exists in the common numeric string common2, the following steps need to be performed:

[0053] The digital string L1151:001......100 corresponding to the fifth row and the first image strip of the first sub-image is ORed with the common digital string common2:001......100 to obtain the first unique bit 000......000, a total of 64 bits, represented by unique12; the digital string L1252:011......111 corresponding to the fifth row and the second image strip of the first second sub-image is ORed with the common digital string common2:001......100 to obtain the second unique bit 010......011, a total of 64 bits, represented by unique22.

[0054] Finally, compare common2, unique12 and unique22 one by one and output the comparison result 2. The comparison result 2 contains a total of 128 bytes, that is, two bits are used to represent one pixel. The specific comparison is as follows: the first bit from the left is 0,0,0, and the output is 00, corresponding to Figure 2 In the third image strip of the fifth row of the first sub-image, the first bit from the left is displayed as a white pixel; the second bit from the left is 0, 0, 1, and the output is 01, corresponding to Figure 2 The second bit from the left of the third image strip in the fifth row of the first third sub-image is displayed as the first color pixel; the third bit from the left is 1, 0, 0 respectively. Since the common bit is 1, 11 is directly output, corresponding to Figure 2 The third pixel from the left in the third image strip of the fifth row of the first third sub-image is displayed as a black pixel. That is, for any corresponding first and second image strips that are not identical, in the shared digital string obtained by performing an AND operation, the corresponding pixel of the first image strip corresponding to 1 in the shared digital string does not need to be further ORed with the number 1 in the shared digital string, and is represented by " / " in the first unique bit unique12, which generally defaults to the number 0; the corresponding pixel of the second image strip corresponding to 1 in the shared digital string does not need to be further ORed with the number 1 in the shared digital string, and is represented by " / " in the second unique bit unique22, which generally defaults to the number 0; finally, the corresponding position in the third image strip of the corresponding third sub-image is directly filled with a black pixel color. The 62nd bit from the left is the same as the 3rd bit from the left, and will not be repeated here; the 63rd bit from the left and the 64th bit from the left are the same as the 2nd bit from the left, and will not be repeated here.

[0055] final, Figure 2 The pixel colors of the third image strip in the fifth row of the first third sub-image are: white, second color, black (first three bits) .... black, second color, second color (last 64 bits).

[0056] In the same way as the first third sub-image is obtained, the second third sub-image is obtained by comparing the second first sub-image of the first image and the second second sub-image of the second image in the first image.

[0057] In the same way as the first third sub-image is obtained, the second third sub-image is obtained by comparing the second first sub-image of the first image and the second second sub-image of the second image in the first image. Figure 2

[0058] Finally, the two third sub-images are sequentially placed into the storage squares in the third image to splice the third image. Figure 2

[0059] The comparison result of the first image and the second image can be directly reflected from the third image.

[0060] In the present application, the first color is exemplarily taken as red, and the second color is exemplarily taken as blue. The first color needs to be different from black and white, and the second color needs to be different from the first color.

[0061] In the present application, M is taken as 11, N is taken as 128, and K is taken as 2, which are only exemplary. Both of the two first sub-images include 64 columns, which are exemplary. In the two first sub-images, the first one can include 60 columns, and the second one can include 68 columns, and the specific number is not limited. Similarly, K can be taken as 3, and the column number of each one is exemplarily taken as 40, 50, and 38, respectively. However, it is necessary to stipulate that the row and column numbers of the second image must be the same as those of the first image, and the row and column numbers of the third image must be the same as those of the first image. The number of the third sub-image is the same as that of the first sub-image. The row and column numbers of each third sub-image are completely the same as those of the corresponding first sub-image or second sub-image.

[0062] In the present application, the larger M and N are, the larger the memory of the first image and the second image is, and the larger the memory of the third image obtained by comparing the first image and the second image is. Through the third image, the difference between the first image and the second image can be quickly distinguished.

[0063] Finally, it should be noted that the above is only the preferred embodiment of the present application, and is not used to limit the present application. Although the present application has been described in detail with reference to the foregoing embodiments, those skilled in the art can still modify the technical solutions recorded in the foregoing embodiments, or equivalently replace some technical features, as long as they are within the spirit and principle of the present application. Any modification, equivalent replacement, improvement, etc. made within the scope of the present application shall be included in the protection scope of the present application.​​

Claims

1. A method for comparing large images, characterized in that: include: Step 1: Define the first image and the second image to consist of M rows × N columns of pixels, with each pixel being 1 bit in size, and define the storage space of the third image to be M rows × N columns of storage grids; Step 2: Divide the first image into K first sub-images in a left-to-right or right-to-left order, where each first sub-image includes M rows × L columns of pixels, where N = K × L. Divide the second image into K second sub-images in the same division order as the first image. Step 3: Compare the K first sub-images of the first image with the K second sub-images of the second image one by one in sequence to obtain K third sub-images, and sequentially store the K third sub-images into the storage space of the third image, and stitch the K third sub-images into a third image; In step 3, K first sub-images of the first image are sequentially compared with K second sub-images of the second image to obtain K third sub-images, which specifically includes: Step 31: Compare any first sub-image among the K first sub-images of the first image with the corresponding second sub-image of the second image to obtain a third sub-image; Step 32: Using the same approach as step 31, compare the remaining (K-1) first sub-images with the corresponding (K-1) second sub-images one by one to obtain (K-1) third sub-images; Step 31 includes: Step 311: If L pixels of a first image strip in one row of any first sub-image are completely identical to L pixels of a second image strip in a corresponding row of the corresponding second sub-image after a one-to-one comparison, then the third image strip displayed in that row of the third sub-image is identical to the first image strip or the second image strip; Step 312: If the L pixels of a first image strip in one row of any first sub-image are not completely consistent with the L pixels of a second image strip in a corresponding row of the corresponding second sub-image after a one-to-one comparison, proceed as follows: Step 312A: Perform a bitwise AND operation on the L strings of numbers including 0 and / or 1 in the L pixels of a first image strip in one row of any first sub-image and the L strings of numbers including 0 and / or 1 in the L pixels of a second image strip in a corresponding row of the second sub-image, to obtain L common bits including 0 and / or 1. Step 312B: If there is at least one digit 1 in the common bits, then the corresponding pixel of the third image strip in the corresponding row of the third sub-image corresponding to each digit 1 is a black pixel, and the byte of the black pixel is defined as a 2-bit digit string 11; Step 312C: If there is at least one digit 0 in the common digits, perform the following operations: Step 312C1: If the number of the corresponding pixel in the first image strip of the corresponding row of the first sub-image corresponding to the number 0 in the shared bit is ORed with the corresponding number 0 in the shared bit, and the result of the OR operation is 0, and the number of the corresponding pixel in the second image strip of the corresponding row of the second sub-image corresponding to the number 0 in the shared bit is ORed with the number 0 in the shared bit, then the corresponding pixel in the third image strip of the corresponding row of the third sub-image is a white pixel, and the size of the white pixel is 2 bits, represented by the digital string 00; Step 312C2: If the result of an OR operation between the corresponding pixels of the corresponding row and the corresponding first image strip of the first sub-image corresponding to the number 0 in the shared bit and the number 0 in the shared bit is 1, and the result of an OR operation between the corresponding pixels of the corresponding row and the second image strip of the second sub-image corresponding to the number 0 in the shared bit and the number 0 in the shared bit is 0, then the corresponding pixels of the corresponding row and the third image strip of the corresponding third sub-image are first color pixels other than white pixels and black pixels, and the size of the first color pixel is 2 bits, represented by the digital string 10; Step 312C3: If the result of an OR operation between the corresponding pixel of the first image strip in the corresponding row of the first sub-image corresponding to the number 0 in the shared bit and the number 0 in the shared bit is 0, and the result of an OR operation between the corresponding pixel of the second image strip in the corresponding row of the second sub-image corresponding to the number 0 in the shared bit and the number 0 in the shared bit is 1, then the corresponding pixel of the third image strip in the corresponding row of the third sub-image is a second color pixel other than white pixels, black pixels, and first color pixels, and the size of the second color pixel is 2 bits and is represented by the string 01; The order of steps 312B and 312C is not specific; the order of steps 312C1 to 312C3 is not specific; In the first image and the second image, the number 0 represents a white pixel and the number 1 represents a black pixel; in the third image, each pixel has a size of 2 bits, and the pixel color is at least black or white, the number 00 represents a white pixel and the number 11 represents a black pixel.

2. The large image comparison method according to claim 1, wherein: The first color pixel is a red pixel, and the second color pixel is a blue pixel.

Images