An image processing apparatus comprising: a first-part-information obtaining part configured to obtain first part information from a first range image obtained by imaging a first area of a subject, the first part information being information on a part of the subject; a second-part-information obtaining part configured to obtain second part information from a second range image obtained by imaging a second area of the subject smaller than the first area, the second part information being information on a part of the subject; a transformation-function generation part configured to find a transformation function based on the first part information and the second part information, the transformation function being a function that performs coordinate transformation between a first coordinate system in the first part information and a second coordinate system in the second part information; and a combined-part-information generation part configured to generate combined part information based on the transformation function, the combined part information being information representing the first part information and the second part information in a common coordinate system, wherein the image processing apparatus is further comprising: a first reception part configured to receive the first range image, sent from a first-range-image obtaining apparatus; and a second reception part configured to receive the second range image, sent from a second-range-image obtaining apparatus, wherein the first range image obtaining apparatus is fixed to an upper end portion of a fixing instrument standing to a predetermined height from the floor surface, characterized in that: the second-range-image obtaining apparatus is mounted on an item so that when the subject is wearing the item the first area is an area covering a whole body of the subject, and the second area is an area covering a body part of the subject, wherein the subject is a person. a first-part-information obtaining part configured to obtain first part information from a first range image obtained by imaging a first area of a subject, the first part information being information on a part of the subject; a second-part-information obtaining part configured to obtain second part information from a second range image obtained by imaging a second area of the subject smaller than the first area, the second part information being information on a part of the subject; a transformation-function generation part configured to find a transformation function based on the first part information and the second part information, the transformation function being a function that performs coordinate transformation between a first coordinate system in the first part information and a second coordinate system in the second part information; and a combined-part-information generation part configured to generate combined part information based on the transformation function, the combined part information being information representing the first part information and the second part information in a common coordinate system, wherein the image processing apparatus is further comprising: a first reception part configured to receive the first range image, sent from a first-range-image obtaining apparatus; and a second reception part configured to receive the second range image, sent from a second-range-image obtaining apparatus, wherein the first range image obtaining apparatus is fixed to an upper end portion of a fixing instrument standing to a predetermined height from the floor surface, characterized in that: the second-range-image obtaining apparatus is mounted on an item so that when the subject is wearing the item the first area is an area covering a whole body of the subject, and the second area is an area covering a body part of the subject, wherein the subject is a person. a first reception part configured to receive the first range image, sent from a first-range-image obtaining apparatus; and a second reception part configured to receive the second range image, sent from a second-range-image obtaining apparatus, wherein the first range image obtaining apparatus is fixed to an upper end portion of a fixing instrument standing to a predetermined height from the floor surface, characterized in that: the second-range-image obtaining apparatus is mounted on an item so that when the subject is wearing the item the first area is an area covering a whole body of the subject, and the second area is an area covering a body part of the subject, wherein the subject is a person.