Image processing apparatus, image processing method, and storage medium to estimate reflection characteristic of object

An image processing apparatus comprising:

• a first acquisition unit configured to acquire shape information indicating a shape of a surface of an object;
• a second acquisition unit configured to acquire a plurality of pieces of image data acquired by imaging the object under a plurality of geometric conditions;
• a determination unit configured to determine a pixel position corresponding to a position on the object that has a surface orientation the same as or similar to a surface orientation of a certain surface on the object, for estimating a reflection characteristic of the object corresponding to the surface orientation of the certain surface, in an image indicated by each of the plurality of pieces of image data, based on the shape information;
• and
• an estimation unit configured to estimate the reflection characteristic of the object corresponding to the surface orientation of the certain surface by fitting a reflection model to a pixel value at the pixel position determined by the determination unit.

An image processing apparatus comprising:

• a first acquisition unit configured to acquire shape information indicating a shape of a surface of an object;
• a second acquisition unit configured to acquire a plurality of pieces of image data acquired by imaging the object under a plurality of geometric conditions;
• and
• an estimation unit configured to estimate a reflection characteristic of the object by fitting a reflection model to based on the shape information and the plurality of pieces of image data,
• wherein a pixel position used in fitting of the reflection model in each of images indicated by the plurality of pieces of image data varies according to the shape information.

An image processing method comprising:

• acquiring shape information indicating a shape of a surface of an object as first acquiring;
• acquiring a plurality of pieces of image data acquired by imaging the object under a plurality of geometric conditions as second acquiring;
• determining a pixel position corresponding to a position at which a surface orientation is the same as or similar to a surface orientation at a position of interest on the object, for estimating a reflection characteristic of the object at the position of interest, in a plurality of images indicated by the plurality of pieces of image data, based on the shape information;
• and
• estimating the reflection characteristic of the object at the position of interest by fitting a reflection model to a pixel value at the pixel position determined by the determining.

A non-transitory computer-readable storage medium storing instructions that, when executed by a computer, cause the computer to perform an image processing method, the image processing method comprising:

• acquiring shape information indicating a shape of a surface of an object as first acquiring;
• acquiring a plurality of pieces of image data acquired by imaging the object under a plurality of geometric conditions as second acquiring;
• determining a pixel position corresponding to a position at which a surface orientation is the same as or similar to a surface orientation at a position of interest on the object, for estimating a reflection characteristic of the object at the position of interest, in a plurality of images indicated by the plurality of pieces of image data, based on the shape information;
• and
• estimating the reflection characteristic of the object at the position of interest by fitting a reflection model to a pixel value at the pixel position determined by the determining.