Abstract: The present disclosure discloses a method, which includes: obtaining, by controlling to move an electron beam to scan a sample, a diffraction intensity of the sample at each scanning position; initializing a sample transmission function and an electron beam function, establishing, based on the diffraction intensity, the sample transmission function, and the electron beam function, a forward propagation model containing to-be-optimized parameters, and calculating a value of a loss function; solving a derivative of the loss function with respect to the to-be-optimized parameters, to obtain gradients of the to-be-optimized parameters in the sample transmission function and the electron beam function, optimizing the to-be-optimized parameters based on the gradients, and updating the value of the loss function; and repeating an iteration process until an iteration termination condition is satisfied, and outputting an optimized sample transmission function and an optimized electron beam function.

Abstract: Provided are a watermarking method and a watermarking apparatus for a mesh mode, which are applicable to a system which requires high precision, such as a rapid prototyping system. A reference coordinate system is set using 1-ring values of vertices of a 3D mesh model. The vertices are sorted based on the set reference coordinate system, and bit-information of the watermark consisting of bit string is, respectively, embedded into each of polygonal faces of the 3D mesh model in the sorted order. The present invention is advantageous in that the shape of the model is not deformed even when watermarked, and therefore the present invention is useful in a rapid prototyping system which requires high precision for the purpose of authenticating data integrity. The present invention can be also used for the purpose of marking contents without the need for storing, and for the purpose of information hiding.

Abstract: Provided are a watermarking method and a watermarking apparatus for a mesh mode, which are applicable to a system which requires high precision, such as a rapid prototyping system. A reference coordinate system is set using 1-ring values of vertices of a 3D mesh model. The vertices are sorted based on the set reference coordinate system, and bit-information of the watermark consisting of bit string is, respectively, embedded into each of polygonal faces of the 3D mesh model in the sorted order. The present invention is advantageous in that the shape of the model is not deformed even when watermarked, and therefore the present invention is useful in a rapid prototyping system which requires high precision for the purpose of authenticating data integrity. The present invention can be also used for the purpose of marking contents without the need for storing, and for the purpose of information hiding.