Printing apparatus, method of printing, and recording medium to actualize the method

A printer having a print head that enables creation of at least two variable-size dots, that is, a larger-size dot and a smaller-size dot, said printer driving said print head and carrying out both main scan and sub-scan to print an image, said printer comprising:

• a contour pixel extraction unit that extracts contour pixels based on image data, the contour pixels representing the contour of a shape included in the image;
• a dot creation decision unit that determines creation or non creation of each of the at least two variable-size dots with regard to each pixel based on the image data, and allocates the smaller-size dot to each of the contour pixels extracted by said contour pixel extraction unit;
• and
• a dot creation unit that actually creates the at least two variable-size dots, based on results of the determination and the allocation with regard to the respective pixels by said dot creation decision unit,
• wherein said contour pixel extraction unit defines a plurality of adjoining pixels in a main scanning direction as one set, compares a tone value of each pixel included in the set with a predetermined threshold value, and extracts the contour pixels based on a result of the comparison.

A printer having a print head that enables creation of at least two variable-size dots, said printer driving said print head and carrying out both main scan and sub-scan to print an image, said printer comprising:

• a resolution reduction unit that collects every preset number of adjoining pixels among all the pixels constituting the image into one large pixel based on a predetermined relationship, and expresses the image with large pixels;
• a contour pixel extraction unit that extracts contour large pixels based on image data, the contour large pixels representing the contour of a shape included in the image;
• a dot creation decision unit that determines creation or non-creation of each of the at least two variable-size dots with regard to each large pixel based on the image data, and selects one of the at least two variable-size dots, which is to be created in each of the extracted contour large pixels, based on the image data with regard to the preset number of adjoining pixels collected into the contour large pixel;
• and
• a dot creation unit that actually creates the at least two variable-size dots, based on results of the determination and the selection with regard to the respective large pixels by said dot creation decision unit.

A printer having a print head that enables creation of at least two variable-size dots, said printer driving said print head and carrying out both main scan and sub-scan to print an image, said printer comprising:

• a contour pixel extraction unit that extracts contour pixels based on image data, the contour pixels representing the contour of a shape included in the image;
• a dot creation decision unit that determines creation or non-creation of each of the at least two variable-size dots with regard to each pixel based on the image data, said dot creation decision unit dividing each of the contour pixels into a plurality of adjoining small pixels and selecting one of the at least two variable-size dots, which is to be created in each of the contour pixels, based on tone values of the respective small pixels that are specified according to a predetermined relationship;
• and
• a dot creation unit that actually creates the at least two variable-size dots, based on results of the determination and the selection with regard to the respective pixels by said dot creation decision unit.

A method of driving a print head and carrying out both main scan and sub-scan to print an image, said print head enabling creation of at least two variable-size dots, that is, a larger-size dot and a smaller-size dot, said method comprising the steps of:

• (a) extracting contour pixels based on image data, the contour pixels representing the contour of a shape included in the image;
• (b) determining creation or non-creation of each of the at least two variable-size dots with regard to each pixel based on the image data, and allocating the smaller-size dot to each of the contour pixels extracted in said step (a);
• and
• (c) actually creating the at least two variable-size dots, based on results of the determination and the allocation with regard to the respective pixels in said step (b).

A method of driving a print head and carrying out both main scan and sub-scan to print an image, said print head enabling creation of at least two variable-size dots, said method comprising the steps of:

• (a) collecting every preset number of adjoining pixels among all the pixels constituting the image into one large pixel based on a predetermined relationship, and expressing the image with large pixels;
• (b) extracting contour large pixels based on image data, the contour large pixels representing the contour of a shape included in the image;
• (c) determining creation or non-creation of each of the at least two variable-size dots with regard to each large pixel based on the image data, and selecting one of the at least two variable-size dots, which is to be created in each of the extracted contour large pixels, based on the image data with regard to the preset number of adjoining pixels collected into the contour large pixel;
• and
• (d) actually creating the at least two variable-size dots, based on results of the determination and the selection with regard to the respective large pixels in said step (c).

A method of driving a print head and carrying out both main scan and sub-scan to print an image, said print head enabling creation of at least two variable-size dots, said method comprising the steps of:

• (a) extracting contour pixels based on image data, the contour pixels representing the contour of a shape included in the image;
• (b) determining creation or non-creation of each of the at least two variable-size dots with regard to each pixel based on the image data, dividing each of the contour pixels into a plurality of adjoining small pixels, and selecting one of the at least two variable-size dots, which is to be created in each of the contour pixels, based on tone values of the respective small pixels that are specified according to a predetermined relationship;
• and
• (c) actually creating the at least two variable-size dots, based on results of the determination and the selection with regard to the respective pixels in said step (b).

A recording medium, on which a program is recorded in a computer readable manner, said program being used in a printer that enables creation of at least two variable-size dots, said program being activated to carry out a predetermined operation for image data representing the image, in order to determine creation or non-creation of each of the at least two variable-size dots, said program comprising:

• a program code that causes a computer to collect every preset number of adjoining pixels among all the pixels constituting the image into one large pixel based on a predetermined relationship, and to express the image with large pixels;
• a program code that causes the computer to extract contour large pixels based on image data, the contour large pixels representing the contour of a shape included in the image;
• and
• a program code that causes the computer to determine creation or non-creation of each of the at least two variable-size dots with regard to each large pixel based on the image data, and to select one of the at least two variable-size dots, which is to be created in each of the extracted contour large pixels, based on the image data with regard to the preset number of adjoining pixels collected into the contour large pixel.