Image processing apparatus and method, data, and recording medium

An image processing method, comprising:

• capturing an image of a structured light pattern which is projected on a screen, wherein
• the structured light pattern comprises a plurality of patterns,
• a partial region, of the structured light pattern, of a specific size comprises a pattern group,
• the plurality of patterns corresponds to four kinds of patterns,
• the four kinds of patterns are combinations of at least a first kind of pattern with a first kind of luminance distribution having a first luminance variation direction, and at least a second kind of pattern with a second kind of luminance distribution having a second luminance variation direction,
• the first luminance variation direction is opposite to the second luminance variation direction, and
• a principal axis of inertia in the first luminance variation direction is different from a principal axis of inertia in the second luminance variation direction;
• converting the pattern group of the partial region into a plurality of variables;
• obtaining a first code string based on a permutation expansion of the plurality of variables, wherein
• the plurality of patterns is in the structured light pattern such that a position of the partial region is uniquely determinable based on the first code string;
• searching, within a group of code strings, for a second code string which is coincident with the first code string, wherein
• the first code string corresponds to a set of patterns of the plurality of patterns in the captured image, and
• the group of code strings corresponds to a plurality of partial regions of the structured light pattern;
• and
• detecting a plurality of corresponding points between a projection image projected on the screen and the captured image, based on the second code string and the position of the partial region of the structured light pattern,
• wherein the second code string coincides with the partial region of the structured light pattern.

An image processing apparatus, comprising:

• a central processing unit (CPU) configured to:
• generate a structured light pattern comprising a plurality of patterns, wherein
• a partial region, of the structured light pattern, of a specific size comprises a pattern group;
• control capture of an image of the structured light pattern which is projected on a screen, wherein
• the plurality of patterns corresponds to four kinds of patterns,
• the four kinds of patterns are combinations of at least a first kind of pattern with a first kind of luminance distribution having a first luminance variation direction, and at least a second kind of pattern with a second kind of luminance distribution having a second luminance variation direction,
• the first luminance variation direction is opposite to the second luminance variation direction, and
• a principal axis of inertia in the first luminance variation direction is different from a principal axis of inertia in the second luminance variation direction;
• convert the pattern group of the partial region into a plurality of variables;
• obtain a first code string based on a permutation expansion of the plurality of variables,
• wherein the plurality of patterns is in the structured light pattern such that a position of the partial region is uniquely determinable based on the first code string;
• search, within a group of code strings, for a second code string which is coincident with the first code string, wherein
• the first code string corresponds to a set of patterns of the plurality of patterns in the captured image, and
• the group of code strings corresponds to a plurality of partial regions of the structured light pattern;
• and
• detect a plurality of corresponding points between a projection image projected on the screen and the captured image, based on the second code string and the position of the partial region of the structured light pattern,
• wherein the second code string coincides with the partial region of the structured light pattern.

An image processing method, comprising:

• generating a structured light pattern comprising a plurality of patterns, wherein
• a partial region, of the structured light pattern, of a specific size comprises a pattern group;
• capturing an image of the structured light pattern which is projected on a screen, wherein
• the plurality of patterns corresponds to four kinds of patterns,
• the four kinds of patterns are combinations of at least a first kind of pattern with a first kind of luminance distribution having a first luminance variation direction, and at least a second kind of pattern with a second kind of luminance distribution having a second luminance variation direction,
• the first luminance variation direction is opposite to the second luminance variation direction, and
• a principal axis of inertia in the first luminance variation direction is different from a principal axis of inertia in the second luminance variation direction;
• converting the pattern group of the partial region into a plurality of variables;
• obtaining a first code string based on a permutation expansion of the plurality of variables,
• wherein the plurality of patterns is in the structured light pattern such that a position of the partial region is uniquely determinable based on the first code string;
• searching, within a group of code strings, for a second code string which is coincident with the first code string, wherein
• the first code string corresponds to a set of patterns of the plurality of patterns in the captured image, and
• the group of code strings corresponds to a plurality of partial regions of the structured light pattern;
• and
• detecting a plurality of corresponding points between a projection image projected on the screen and the captured image, based on the second code string and the position of the partial region of the structured light pattern,
• wherein the second code string coincides with the partial region of the structured light pattern.

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

• controlling capture of an image of a structured light pattern which is projected on a screen, wherein
• the structured light pattern comprises a plurality of patterns,
• a partial region, of the structured light pattern, of a specific size comprises a pattern group,
• the plurality of patterns corresponds to four kinds of patterns,
• the four kinds of patterns are combinations of at least a first kind of pattern with a first kind of luminance distribution having a first luminance variation direction, and at least a second kind of pattern with a second kind of luminance distribution having a second luminance variation direction,
• the first luminance variation direction is opposite to the second luminance variation direction, and
• a principal axis of inertia in the first luminance variation direction is different from a principal axis of inertia in the second luminance variation direction;
• converting the pattern group of the partial region into a plurality of variables;
• obtaining a first code string based on a permutation expansion of the plurality of variables,
• wherein the plurality of patterns is in the structured light pattern such that a position of the partial region is uniquely determinable based on the first code string;
• searching, within a group of code strings, for a second code string which is coincident with the first code string, wherein
• the first code string corresponds to a set of patterns of the plurality of patterns in the captured image, and
• the group of code strings corresponds to a plurality of partial regions of the structured light pattern;
• and
• detecting a plurality of corresponding points between a projection image projected on the screen and the captured image, based on the second code string and the position of the partial region of the structured light pattern,
• wherein the second code string coincides with the partial region of the structured light pattern.

An image processing apparatus, comprising:

• a central processing unit (CPU) configured to:
• control capture of an image of a structured light pattern which is projected on a screen, wherein
• the structured light pattern comprises a plurality of patterns,
• a partial region, of the structured light pattern, of a specific size comprises a pattern group,
• the plurality of patterns is disposed in the structured light pattern such that a position of the partial region is uniquely determinable based on a first code string,
• the plurality of patterns corresponds to four kinds of patterns,
• the four kinds of patterns are combinations of at least a first kind of pattern with a first kind of luminance distribution having a first luminance variation direction, and at least a second kind of pattern with a second kind of luminance distribution having a second luminance variation direction,
• the first luminance variation direction is opposite to the second luminance variation direction, and
• a principal axis of inertia in the first luminance variation direction is different from a principal axis of inertia in the second luminance variation direction;
• convert the pattern group of the partial region into a plurality of variables;
• obtain the first code string based on a permutation expansion of the plurality of variables;
• and
• detect a plurality of corresponding points between a projection image projected on the screen and the captured image, based on a second code string.