Image conversion method, image conversion device, and image conversion program

An image conversion device for converting a raster format into a vector format, comprising:

• a division unit that divides an input image represented in a raster format into a plurality of divided regions of a predetermined size;
• a single-color conversion unit that uses the luminance of red, green, and blue of all pixels in the divided region to calculate respective luminance averages for red, green, and blue in the divided region, provides three single-color regions of red, green, and blue in the divided region, and changes the sizes of the single-color regions of red, green, and blue, respectively, according to the luminance averages of red, green, and blue in the divided region;
• and
• an output unit that generates and outputs image data in a vector format using the single-color regions of red, green, and blue.

A non-transitory computer-readable medium having computer-executable instructions stored thereon that, when executed by a processor, cause the processor to perform a method comprising:

• dividing an input image in a raster format into a plurality of divided regions having a predetermined size;
• using the luminance of red, green, and blue of all pixels in the divided region to calculate respective luminance averages for red, green, and blue in the divided region;
• providing three single-color regions of red, green, and blue within the divided region;
• changing the sizes of the single-color regions of red, green, and blue, respectively, according to the luminance averages of red, green, and blue in the divided region;
• and
• generating and outputting an image data in a vector format using the single-color regions of red, green, and blue.