抄録
We have developed a character coding watermarking technique based on computer generated holograms (CGHs).Phase information is converted into intensity information where sampling dots of intensity on a CGH surface are expressed by a character pattern.We have demonstrated the effectiveness of this technique through a simulated recovery of CGH data by using the character pattern.Further more, we propose a quadrant distribution of character pattern against cropping attack.It shows that the sampling dots are increased by 100 percent against the same cropping attack.As well, the resolution of the reconstructed image is improved.
