Robust watermark technique using masking and Hermite transform.
The following paper evaluates a watermark algorithm designed for digital images by using a perceptive mask and a normalization process, thus preventing human eye detection, as well as ensuring its robustness against common processing and geometric attacks. The Hermite transform is employed because it allows a perfect reconstruction of the image, while incorporating human visual system properties; moreover, it is based on the Gaussian functions derivates. The applied watermark represents information of the digital image proprietor. The extraction process is blind, because it does not require the original image. The following techniques were utilized in the evaluation of the algorithm: peak signal-to-noise ratio, the structural similarity index average, the normalized crossed correlation, and bit error rate. Several watermark extraction tests were performed, with against geometric and common processing attacks. It allowed us to identify how many bits in the watermark can be modified for its adequate extraction.
Departamento de Ingeniería, Instituto Politécnico Nacional, UPIITA, Av. IPN No. 2580. Col. La Laguna Ticomán, 07340 Mexico, D.F. Mexico.
Sandra L Gomez
SL
Coronel
Departamento de Procesamiento Digital de Señales, Universidad Nacional Autóma de México, Mexico, D.F. Mexico.
Boris Escalante
BE
Ramírez
Sección de Estudios de Posgrado e Investigación, Area Telecomunicaciones, Instituto Politécnico Nacional, ESIME Zacatenco, Mexico, D.F. Mexico.
Marco A Acevedo
0000-0002-3535-1164
MA
Mosqueda
Hermite transform; Image normalization; Perceptive mask; Robustness; Spread spectrum; Watermarking