In this paper, we shall describe the spatial projection of holographic reconstructed images employing the blue-violet laser light. Firstly, construction of mist screen is introduced, and the conditions under which optical characteristics of the screen will be improved are reported. Evaluation of improved situation is carried out by objective and subjective evaluating technics. Reconstructed images obtained by projecting blue-violet laser light are shown, and a relation between the usage of two kinds of fans and the quality of the projected images (brightness and stability) is studied. It is carried out by combining optical characteristics (objective evaluation), subjective evaluation and automatic decision making based on image analyzing process. By this, a certain relation is seen to exist between the result derived from each of the evaluating processes and the projected image judged as “good”. Using this result, it is found that a clear projection of the images by blue-violet laser light is really possible.

We propose a robust watermarking method based on a hybrid watermarking system using the green noise diffusion watermarking (GN) method and the block patchwork watermarking (BP) method. In general, the GN method loses the embedded green noise patterns when the image is highly compressed by JPEG, strongly smoothed, or scaled down by a large factor of change, and the correct extraction rate is reduced. We have solved this problem by using the hybrid type watermarking method that incorporates the watermarking method using the BP method, and by using adaptive embedding for both methods. The results showed that the hybrid watermarking method almost meets the IHC evaluation criteria (evaluation criteria for watermarking established by the Information Hiding and its Criteria for evaluation study group).