A three-dimensional shape measurement method, comprising: a) using an imaging unit arranged for outputting: - a captured first two-dimensional images, and - a second two-dimensional image according to a predetermined output instruction; the method further comprising: b) generating the output instruction on the basis of a shape defect rate in viewing a three-dimensional model from a perspective of having captured the first two-dimensional image, the three-dimensional model being based on the second two-dimensional image outputted by the imaging unit, wherein, when said three-dimensional model is represented as a calculated two-dimensional image (Ip) from a given perspective of having captured the first two-dimensional image, said shape defect rate corresponds to a ratio of: - the number of pixels of said calculated two-dimensional image (Ip), in which a shape is drawn, over - the number of pixels of at least one part of region (Ib) of said first two-dimensional image captured from said given perspective, respective image resolutions of said calculated two-dimensional image (Ip) and said first two-dimensional image (Ib) being taken into account in a calculation of said ratio; and - if said shape defect rate is below a threshold (Xt), using said imaging unit to acquire a new second two-dimensional image, and repeat step b) with said new second two-dimensional image, - otherwise, if said shape defect rate is equal or above said threshold (Xt), storing the second two-dimensional image outputted by the imaging unit, and wherein the first two-dimensional image and the second two-dimensional image are depth images. a) using an imaging unit arranged for outputting: - a captured first two-dimensional images, and - a second two-dimensional image according to a predetermined output instruction; - a captured first two-dimensional images, and - a second two-dimensional image according to a predetermined output instruction; b) generating the output instruction on the basis of a shape defect rate in viewing a three-dimensional model from a perspective of having captured the first two-dimensional image, the three-dimensional model being based on the second two-dimensional image outputted by the imaging unit, wherein, when said three-dimensional model is represented as a calculated two-dimensional image (Ip) from a given perspective of having captured the first two-dimensional image, said shape defect rate corresponds to a ratio of: - the number of pixels of said calculated two-dimensional image (Ip), in which a shape is drawn, over - the number of pixels of at least one part of region (Ib) of said first two-dimensional image captured from said given perspective, respective image resolutions of said calculated two-dimensional image (Ip) and said first two-dimensional image (Ib) being taken into account in a calculation of said ratio; and - if said shape defect rate is below a threshold (Xt), using said imaging unit to acquire a new second two-dimensional image, and repeat step b) with said new second two-dimensional image, - otherwise, if said shape defect rate is equal or above said threshold (Xt), storing the second two-dimensional image outputted by the imaging unit, and wherein - the number of pixels of said calculated two-dimensional image (Ip), in which a shape is drawn, over - the number of pixels of at least one part of region (Ib) of said first two-dimensional image captured from said given perspective, respective image resolutions of said calculated two-dimensional image (Ip) and said first two-dimensional image (Ib) being taken into account in a calculation of said ratio; and - if said shape defect rate is below a threshold (Xt), using said imaging unit to acquire a new second two-dimensional image, and repeat step b) with said new second two-dimensional image, - otherwise, if said shape defect rate is equal or above said threshold (Xt), storing the second two-dimensional image outputted by the imaging unit, and wherein