Computer-readable storage medium storing image processing program, image processing device, and image processing method

1. A non-transitory computer readable storage medium storing computer-readable instructions, when executed by processor of an image processing device, causing the image processing device to perform processes comprising:

an obtaining process of obtaining image data representing an image;

a first specifying process of specifying a group of pixels with a first color, the first color corresponding to a color of an outline of a hole image in the image;

a second specifying process of specifying an enclosing area in which the group of pixels is included;

a third specifying process of specifying a hole orientation based on positions of the group of pixels, the hole orientation representing a direction that the outline of the hole image occupies; and

an extension process of extending, when the hole orientation is specified by the third specifying process, the enclosing area in an extension direction corresponding to a direction opposite to the hole orientation; and

a determination process of determining a size of the extended enclosing area based on the position of the extended enclosing area with respect to four ends of the image,

the size of the extended enclosing area being larger than a first size in response to the extended enclosing area being separated from four ends of the image,

the size of the extended enclosing area being larger than a second size in response to the extended enclosing area being in contact with at least one of the four ends of the image;

wherein the first size corresponds to the hole image and the second size being smaller than the first size.

2. The non-transitory computer readable medium according to claim 1 , wherein

the determination process further comprises determining, when the extended enclosing area is in contact with the at least one of the four ends of the image and when the hole orientation represents a direction toward the at least one of the four ends of the image, the extended enclosing area larger than a third size as the specific area, the third size being smaller than the first size and larger than the second size.

3. The non-transitory computer readable medium according to claim 2 , wherein the instructions further causes the image processing device to perform processes comprising:

a filtering process of filtering the image data using an edge enhancement filter; and

a binarization process of binarizing the image data filtered by the filtering process, wherein

the first specifying process further comprises specifying the group of pixels in the image represented by the image data filtered by the filtering process and binarized by the binarization process, and wherein

the determination process further comprises determining, when the extended enclosing area is in contact with the at least one of the four ends of the image, the extended enclosing area with the hole orientation toward the at least one of the four ends of the image and larger than the third size as the specific area, the third size being defined by subtracting a predetermined length from the first size, the predetermined length corresponding to a number of pixels corresponding to an increase of thickness of the outline of the hole image by the filtering process.

4. The non-transitory computer readable medium according to claim 2 , wherein

the determination process further comprises determining, when the extended enclosing area is in contact with the at least one of the four ends of the image and when the hole orientation is specified not to correspond to any specific direction, the extended enclosing area larger than the third size as the specific area.

5. The non-transitory computer readable medium according to claim 1 , wherein

the second size is half as large as the first size.

6. The non-transitory computer readable medium according to claim 1 , wherein the third specifying process further comprises:

a division process of dividing the enclosing area specified by the second specifying process into a plurality of grid segments, wherein

the third specifying process further comprises specifying the hole orientation based on an arrangement pattern of first and second grid segments, the first grid segment being the grid segment including one or more pixels with the first color, the second grid segment being the grid segment not including a pixel with the first color.

7. The non-transitory computer readable medium according to claim 1 , wherein the instructions further causes the image processing device to perform processes comprising:

a filling process of filling specific pixels in an original image represented by original image data with a filling color, the specific pixels being included in an area corresponding to the specific area.

8. The non-transitory computer readable medium according to claim 1 , wherein

second specifying process further comprises specifying a quadrangle as the enclosing area, the quadrangle including the group of pixels.

9. The non-transitory computer readable medium according to claim 8 , wherein

the quadrangle circumscribing the group of pixels.

10. An image processing device comprising:

a processor; and

a storage storing computer-readable instructions, when executed by the processor, causing the image processing device to perform processes comprising:

an obtaining process of obtaining image data representing an image;

a first specifying process of specifying a group of pixels with a first color, the first color corresponding to a color of an outline of a hole image in the image;

a second specifying process of specifying an enclosing area in which the group of pixels is included;

a third specifying process of specifying a hole orientation based on positions of the group of pixels, the hole orientation representing a direction that the outline of the hole image occupies; and

an extension process of extending, when the hole orientation is specified by the third specifying process, the enclosing area in an extension direction corresponding to a direction opposite to the hole orientation; and

a determination process of determining a size of the extended enclosing area based on the position of the extended enclosing area with respect to four ends of the image,

the size of the extended enclosing area being larger than a first size in response to the extended enclosing area being separated from four ends of the image,

the size of the extended enclosing area being larger than a second size in response to the extended enclosing area being in contact with at least one of the four ends of the image,

wherein the first size corresponds to the hole image and the second size being smaller than the first size.

11. An image processing method comprising:

obtaining image data representing an image;

specifying a first area including a group of pixels with a first color, the first color corresponding to a color of an outline of a hole image in the image;

specifying a hole orientation based on positions of the group of pixels, the hole orientation representing a direction that the outline of the hole image occupies;

extending the first area in an extension direction corresponding to a direction opposite to the hole orientation; and

determining a size of a second area corresponding to the hole image based on a position of the extended first area with respect to four ends of the image, the second area being larger than a first size in response to the first area being separated from four ends of the image; and larger than a second size in response to the first area being in contact with at least one of the four ends of the image, the second size being smaller than the first size.

12. The image processing method according to claim 11 , further comprising:

specifying the group of pixels with the first color.