Abstract:A watermark method on Fresnel hologram transformation and OFDM for multiple three-dimensional objects has been proposed. First, the fast convolution algorithm is used to calculate the Fresnel diffraction distribution of the single virtual three-dimensional object in the observed plane. Then, combining with OFDM principle procedures such as parallel-serial conversion, conjugate symmetry, IFFT and parallel-serial conversion are followed to design real coding computer-generated holographic watermark. Watermark signal is embedded in the horizontal and vertical detail components of the wavelet domain by changing neighbor wavelet coefficient to hide information and the watermark can be blind extracted. The simulation results show that the approach behaves good robustness on cropping, filtering, JPEG compression, etc. Especially the approach shows good performance for cropping operation.