The invention discloses a phase-
cut Fourier transform based
image hiding method, an image restoring method and an image encrypted transmission method. The
image hiding method includes: subjecting a to-be-hidden image f to Fourier inverse transform prior to extracting an amplitude matrix g(x, y) and a
phase matrix P(x, y) of the image subjected to Fourier inverse transform, and subjecting a carrier image f1 to
Fourier transform prior to extracting an amplitude matrix g1(u, v) and a
phase matrix P1(u, v) of the image subjected to
Fourier transform; enabling g'1 (u, v)=g1(u, v)+g(x, y), then multiplying the g'1 (u, v) by the P1(u, v), obtaining a hidden result after Fourier transform and extracting an amplitude matrix f'1(x, y) of the hidden result so as to obtain a final hidden result image. The image restoring method is implemented by taking the P(x, y) as a private decryption key and performing the
image hiding method reversely. The phase-
cut Fourier transform based image hiding method, the image restoring method and the image encrypted transmission method have the advantages that difference between the obtained hidden result and the carrier image is small, so that deception is achieved; original information can be restored completely, and the problems of
image quality degradation and the like are avoided; calculated quantity is small, and high safety during encrypted transmission is achieved.