An information processing device for producing motion data describing a motion of a predetermined moving object including a plurality of elements, the information processing device comprising: base data obtaining means for obtaining a sequence of base data each containing an image produced by capturing an image of at least one object at different times, including the moving object, using image capturing means, and distance data indicating a distance between the object shown in the image and the image capturing means, the distance data being based on a measured result at a time of capturing the image, obtained by distance measuring means; in-image position specifying means for specifying an in-image position where each of at least some of the elements included in the moving object is shown in the image, based on the image contained in each of the sequence of base data; distance specifying means for specifying a distance between each of the at least some of the elements included in the moving object and the image capturing means, based on the in-image position specified by the in-image position specifying means and the distance data contained in the base data that contains the image; position coordinate calculating means for calculating position coordinates of each of the at least some of the elements included in the moving object in a 3D space, based on the in-image position specified by the in-image position specifying means and the distance specified by the distance specifying means; and motion data producing means for producing motion data describing a motion of each of the at least some of the elements included in the moving object in the 3D space, based on the position coordinates calculated based on the base data., when position coordinates of a missing element among the plurality of elements included in the moving object are not calculated by the position coordinate calculating means, based on the n-th base data, the position coordinate calculating means calculates the position coordinates of the missing element, based on base data different from the n-th base data among the sequence of base data obtained by the base data obtaining means. base data obtaining means for obtaining a sequence of base data each containing an image produced by capturing an image of at least one object at different times, including the moving object, using image capturing means, and distance data indicating a distance between the object shown in the image and the image capturing means, the distance data being based on a measured result at a time of capturing the image, obtained by distance measuring means; in-image position specifying means for specifying an in-image position where each of at least some of the elements included in the moving object is shown in the image, based on the image contained in each of the sequence of base data; distance specifying means for specifying a distance between each of the at least some of the elements included in the moving object and the image capturing means, based on the in-image position specified by the in-image position specifying means and the distance data contained in the base data that contains the image; position coordinate calculating means for calculating position coordinates of each of the at least some of the elements included in the moving object in a 3D space, based on the in-image position specified by the in-image position specifying means and the distance specified by the distance specifying means; and motion data producing means for producing motion data describing a motion of each of the at least some of the elements included in the moving object in the 3D space, based on the position coordinates calculated based on the base data., when position coordinates of a missing element among the plurality of elements included in the moving object are not calculated by the position coordinate calculating means, based on the n-th base data, the position coordinate calculating means calculates the position coordinates of the missing element, based on base data different from the n-th base data among the sequence of base data obtained by the base data obtaining means.