Abstract: The present invention discloses a privacy masking method using format-preserving encryption in an image security system, and a recording medium for performing the method. In a privacy masking method using format-preserving encryption in an image security system according to an aspect of the present invention, an image corresponding to a privacy region is encrypted using format-preserving encryption, so that it is possible to prevent waste of additional storage space required for encryption and to solve a problem of exposure of personal information.

Abstract: The present invention discloses a privacy masking method using format-preserving encryption in an image security system, and a recording medium for performing the method. In a privacy masking method using format-preserving encryption in an image security system according to an aspect of the present invention, an image corresponding to a privacy region is encrypted using format-preserving encryption, so that it is possible to prevent waste of additional storage space required for encryption and to solve a problem of exposure of personal information.

Abstract: Disclosed are a toy block coupling structure and a toy block comprising same. A toy block, in accordance with one embodiment of the present invention, has a structure in which blocks are provided in a block coupling toy so as to be coupled to each other, and comprises: a coupling protrusion; and a coupling hole into which the coupling protrusion is inserted so as to be coupled, wherein the inner surface of the coupling hole comprises a plane portion capable of coming in line-contact with the outer circumferential surface of the coupling protrusion in the depth direction. Therefore, the coupling force between toy blocks can be stably maintained. In addition, the occurrence of defective toy blocks can be reduced and the coupling force between the toy blocks can be uniformly maintained to be uniform. Furthermore, the coupling of the toy blocks can be facilitated.