@conference {uvigo:noveldetector, title = {Novel Detector Structures for Watermark Extraction in the DCT Domain}, booktitle = {Workshop on Nonlinear Signal and Image Processing}, year = {1999}, month = {June}, publisher = {IEEE-EURASIP}, organization = {IEEE-EURASIP}, address = {Antalya, Turkey}, keywords = {data-hiding, watermarking}, author = {Juan R. Hern{\'a}ndez and Mart{\'\i}n Amado and Fernando P{\'e}rez-Gonz{\'a}lez} }