Finger vein feature template protection method and device

The invention is suitable for the technical field of biological feature recognition, and provides a finger vein feature template protection method and device. The method comprises the steps: S1, carrying out the column expansion of an original vector and a converted original feature vector, and obtaining a feature vector sum x < Rhn; S2, carrying out merging preprocessing on the expanded original vector and the converted original vector, and obtaining a multi-dimensional biological characteristic matrix; S3, generating a double-Gaussian random projection matrix and orthogonally converting the double-Gaussian random projection matrix into a double-Gaussian random orthogonal projection matrix as an external factor; S4, combining the feature matrix with a double-Gaussian random orthogonal projection matrix for operation, and expanding the connection to obtain a one-dimensional processing vector; S5, performing irreversible transformation on the one-dimensional processing vector to obtain a hash code; and S6, cal