Image processing method and apparatus

An image printing method for executing an operation that causes a printing head having a plurality of printing elements to scan a plurality of times on a same line on a printing medium so that different printing elements are used in the plurality of scans to form dots on the same line, and an operation that causes the printing medium to be fed, by at least one of a first feed roller and a second feed roller, between the scans of the printing head, to print an image on the printing medium, comprising the steps:

• a first distributing step for distributing data for the dots to be formed on the same line of a first area on the printing medium by using mask patterns, among the plurality of scans, the dot formation onto the first area being performed in a state where the printing medium is held by both the first feed roller and the second feed roller, the first feed roller being disposed on a upstream side of the printing head in a direction in which the printing medium is fed and the second feed roller being disposed on a downstream side of the printing head in the feed direction;
• and
• a second distributing step for distributing data for the dots to be formed on the same line of a second area different from the first area on the printing medium by using mask patterns, among the plurality of scans, the dot formation onto the second area being performed in a state where the printing medium is held by any one of the first feed roller and the second feed roller,
• wherein the number of scans to the same line of the first area is the same as the number of scans to the same line of the second area, and
• wherein data distribution ratios of the mask patterns used in said first distributing step are different from the data distribution ratios of the mask patterns used in the second distributing step.

An image printing method for executing an scanning operation that causes a printing head having a plurality of printing elements to scan a plurality of times on a same line on a printing medium so that different printing elements are used in the plurality of scans to form dots on the same line, and an feeding operation that causes the printing medium to be fed between the scans of the printing head, to print an image on the printing medium, said method comprising:

• a first distributing step for distributing data for the dots to be formed on the same line of a first area on the printing medium by using mask patterns, among the plurality of scans, the first area being printed during the plurality of scans between which the feeding operation by a first feeding amount is intervened;
• and
• a second distributing step for distributing data for the dots to be formed on the same line of a second area on the printing medium, by using mask patterns, among the plurality of scans, the second area being printed during the plurality of scans between which the feeding operation by a second feeding amount smaller than the first feeding amount is intervened,
• wherein the number of scans to the same line of the first area is the same as the number of scans to the same line of the second area, and
• wherein the mask patterns used for the first distributing step are different from to mask patterns used for the second distributing step.

An image printing apparatus for executing an operation that causes a printing head having a plurality of printing elements to scan a plurality of times on a same line on a printing medium so that different printing elements are used in the plurality of scans to form dots on the same line, and an operation that causes the printing medium to be fed between the scans of the printing head, to print an image on the printing medium, said apparatus comprising:

• first distributing means for, of first and second areas defined on the printing medium in relation to feeding said printing medium, distributing data for the dots to be formed on the same line of the first area by using mark patterns, among the plurality of scans;
• and
• second distributing means for distributing data for the dots to be formed on the same line of the second area, in which a deviation of dot forming location becomes larger than that in the first area, by using mask patterns, among the plurality of scans,
• wherein the number of scans to the same line of the first area is the same as the number of scans to the same line of the second area,
• wherein data distribution ratios of the mask patterns for the plurality of scans, which are used for said first distributing means, are different from the data distribution ratios of the mask patterns for the plurality of scans, which are used for said second distributing means.

An image printing apparatus for executing an operation that causes a printing head having a plurality of printing elements to scan a plurality of times on a same line on a printing medium so that different printing elements are used in the plurality of scans to form dots on the same line, and an operation that causes the printing medium to be fed between the scans of the printing head, to print an image on the printing medium, said apparatus comprising:

• a first roller for feeding the printing medium, the first feed roller being disposed on a upstream side of the printing head in a direction in which the printing medium is fed;
• a second roller for feeding the printing medium, the second feed roller being disposed on a downstream side of the printing head in a direction in which the printing medium is fed;
• first distributing means for distributing the data for the dots to be formed on the same line of a first area on the printing medium by using mask patterns, among the plurality of scans, the dot formation on the first area being performed in a state where the printing medium is held by both the first feed roller and the second feed roller;
• and
• second distributing means for distributing data for the dots to be formed on the same line of a second area different from the first area on the printing medium by using mask patterns, among the plurality of scans, the dot formation onto the second area being performed in a state where the printing medium is held by any one of the first feed roller and the second feed roller,
• wherein the number of scans to the same line of the first area is the same as the number of scans to the same line of the second area, and
• wherein data distribution ratios of the mask patterns used by said first distributing means are different from the data distribution ratios of the mask patterns used by said second distribution means.

An image processing apparatus for executing an scanning operation that causes a printing head having a plurality of printing elements to scan a plurality of times on a same line on a printing medium so that different printing elements are used in the plurality of scans to form dots on the same line, and a feeding operation that causes the printing medium to be fed between the scan of the printing head, to print an image on the printing medium, said apparatus comprising:

• first distributing means for distributing data for the dots to be formed on the same line of a first area on the printing medium by using mask patterns, among the plurality of scans, the first area being printed during the plurality of scans between which the feeding operation by a first feeding amount is intervened;
• and
• second distributing means for distributing data for the dots to be formed on the same line of a second area on the printing medium by using mask patterns, among the plurality of scans, the second area being printed during the plurality of scans between which the feeding operation by a second feeding amount smaller than the first feeding amount is intervened,
• wherein the number of scans to the same line of the first area is the same as the number of scans to the same line of the second area, and
• wherein the mask patterns used for said first distributing means are different from the mask patterns used for the second distributing means.