_copyright.bmp _copyright_small.bmp _key.bmp _lena_std_bw.bmp kcs.bmp key.bmp lena.bmp Wdct1_watermarked.bmp Cdct2_embed.m dct2_recover_mod.m kdct2_recover.m Qdct2_embed_mod.m _copyright.gif fig11.gif fig13s.gif lena3.gif test.jpg