Copy-forgery-inhibited pattern image generation method and image processing apparatus

An apparatus comprising:

• a print controller that causes a printing unit to print on a first sheet, a first image part including dots and a second image part including clusters of dots, wherein the clusters in the second image part are provided more sparsely than the dots are provided in the first image part,
• wherein a density difference between a first position within the first image part and the second image part is different from a density difference between a second position within the first image part and the second image part;
• and
• a user interface that receives, from a user, one of identification information of the first position within the first image part printed on the first sheet and identification information of the second position within the first image part printed on the first sheet,
• wherein the print controller is configured to cause, in accordance with a print instruction given after the reception of the identification information, the printing unit to print, on a second sheet, an image obtained by combining user's document image data and image data which is based on the received information,
• wherein, within the printed image on the second sheet, a part of the printed image corresponding to the image data which is based on the received information includes two parts, one part of the two parts including clusters of dots, the other part of the two parts including dots, and the clusters are provided more sparsely in the one part than the dots are provided in the other part,
• wherein densities of the one part and the other part in the part of the printed image on the second sheet correspond, respectively, to densities of the second image part and the one of the first position and the second position within the first image printed on the first sheet that is associated with the received identification information, and
• wherein
• the density of the one part in the part of the image printed on the second sheet is dependent on a number of the clusters per unit area and a size of the clusters in the one part in the part,
• the density of the other part in the part of the image printed on the second sheet is dependent on a number of dots per unit area and a size of the dots in the other part in the part,
• the density of the second image printed on the first sheet is dependent on a number of the clusters per unit area and a size of the clusters in the second image printed on the first sheet, and
• the density of the one of the first position and the second position within the first image printed on the first sheet that is associated with the received identification information is dependent on a number of dots per unit area and a size of the dots in the one of the first position and the second position within the first image printed on the first sheet.

A system comprising:

• a printing unit that prints a plurality of image parts on a first sheet,
• wherein each of the plurality of image parts includes two parts, one part of which includes clusters of dots and the other part of which includes dots, and the clusters are provided more sparsely in the one part than the dots are provided in the other part,
• wherein a density difference between the one part and the other part in one of the plurality of image parts printed on the first sheet is different from a density difference between the one part and the other part in any other image part of the plurality of image parts printed on the first sheet;
• and
• a user interface that receives, from a user, identification information of one of the plurality of image parts printed on the first sheet,
• wherein the printing unit prints, in accordance with a print instruction given after the reception of the identification information, an image obtained by combining image data which is based on the received identification information and other image data on a second sheet,
• wherein a part of the image printed on the second sheet that corresponds to the image data which is based on the received identification information includes two parts, one part of which includes clusters of dots and the other part of which includes dots, and the clusters are provided more sparsely in the one part than the dots are provided in the other part,
• wherein densities of the one part and the other part in the part of the image printed on the second sheet correspond, respectively, to densities of the one part and the other part of the one of the plurality of image parts printed on the first sheet that is associated with the received identification information, and
• wherein
• the density of the one part in the part of the image printed on the second sheet is dependent on a number of the clusters per unit area and a size of the clusters in the one part in the part,
• the density of the other part in the part of the image printed on the second sheet is dependent on a number of dots per unit area and a size of the dots in the other part in the part,
• the density of the one part of the one of the first image and the second image printed on the first sheet that is associated with the received identification information is dependent on a number of the clusters per unit area and a size of the clusters in the one part of the one of the first image and the second image printed on the first sheet, and
• the density of the other part of the one of the first image and the second image printed on the first sheet that is associated with the received identification information is dependent on a number of dots per unit area and a size of the dots in the other part of the one of the first image and the second image printed on the first sheet.

An apparatus comprising:

• a print controller that causes a printing unit to print a plurality of image parts on a first sheet,
• wherein each of the plurality of image parts includes two parts including dots of a color, one part of which includes clusters of dots, the other part of which includes dots, and the clusters are provided more sparsely in the one part than the dots are provided in the other part,
• wherein a density difference between the one part and the other part in one of the plurality of image parts is different from a density difference between the one part and the other part in any other image part of the plurality of image parts;
• and
• a user interface that receives, from a user, identification information of one of the plurality of printed image parts,
• wherein the print controller is further configured to cause, in accordance with a print instruction given after the reception of the identification information, the printing unit to print another image which is based on the received identification information,
• wherein the another image includes two parts including dots of the color, one part of which includes clusters of dots, the other part of which includes dots, and the clusters are provided more sparsely in the one part than the dots are provided in the other part, and
• wherein densities of the color of the one part and the other part in the another image correspond, respectively, to densities of the color of the one part and the other part of the one of the plurality of image parts associated with the received identification information, and
• wherein
• the density of the color of the one part in the part of the image printed on the second sheet is dependent on a number of the clusters per unit area and a size of the clusters in the one part in the part,
• the density of the color of the other part in the part of the image printed on the second sheet is dependent on a number of dots per unit area and a size of the dots in the other part in the part,
• the density of the one part of the one of the plurality of image parts that is associated with the received identification information is dependent on a number of the clusters per unit area and a size of the clusters in the one part of the one of the plurality of image parts printed on the first sheet, and
• the density of the other part of the one of the plurality of image parts that is associated with the received identification information is dependent on a number of dots per unit area and a size of the dots in the other part of the one of the plurality of image parts printed on the first sheet.

A printing method comprising:

• in accordance with a sample print instruction, printing on a sheet, a sample image corresponding to identification information and including two parts, one part of which includes clusters of dots and the other part of which includes dots, wherein the clusters are provided more sparsely in the one part than the dots are provided in the other part, a density of the one part on the sheet being dependent on a number of the clusters per unit area and sizes of the clusters in the one part on the sheet, and a density of the other part on the sheet being dependent on a number of the dots per unit area and a size of the dots in the other part on the sheet;
• and
• after the printing, setting different identification information;
• in accordance with a print instruction given in a situation that the different identification information has been set, printing on another sheet, a user's document image combined with another image corresponding to the set different identification information,
• wherein the another image includes two parts, one part of which includes clusters of dots and the other part of which includes dots, wherein the clusters are provided more sparsely in the one part than the dots are provided in the other part, a density of the one part on the another sheet being dependent on a number of the clusters per unit area and sizes of the clusters in the one part on the another sheet, and a density of the other part on the another sheet being dependent on a number of the dots per unit area and a size of the dots in the other part on the another sheet, and
• wherein at least one of densities of the one part and the other part in the another image printed on the another sheet is different from densities of the one part and the other part of the sample image printed on the sheet.