TY - CONF T1 - Hexagonal Quantizers are not Optimal for 2-D Data Hiding T2 - Security and Watermarking of Multimedia Contents Y1 - 2003 A1 - Félix Balado A1 - Fernando Pérez-González ED - Ping W. Wong ED - Edward J. Delp KW - data-hiding KW - watermarking JF - Security and Watermarking of Multimedia Contents T3 - Proc. of SPIE CY - Santa Clara, USA VL - 5020 ER -