Contour Detection and Recovery through Bio-Medical Watermarking for Telediagnosis K. Pal 1 , V. H. Mankar 2 , T. S. Das 3 and S. K. Sarkar 4 1 Institute of Radio Physics and Electronics, University of Calcutta, Kolkata, INDIA Department of Electronics and Telecommunication Engineering, Jadavpur University, Kolkata, INDIA 1 koushik.rpe@gmail.com 2 vijaymankar@yahoo.com 3 tirthasankardas@yahoo.com 4 sksarkar@etce.jdvu.ac.in ABSTRACT The current paper presents a medical watermarking method through contour detection and recovery for the authenticity of bio-medical images, which uses the region growing algorithm and human visual system (HVS). The proposed scheme makes the use of neighbourhood region for converting non-specific discontinuous region into specific continuous contour data. This contour as a fragile watermark is embedded in the perceptually insignificant, spatially selected detail coefficients using sub band adaptive threshold scheme along with the EPR as a robust one. Here, a new type of non-oblivious detection method is also proposed. The improvement in performance is supported through experimental results. The reported result shows improvement in visual and statistical invisibility of the hidden data. Moreover, this algorithmic architecture utilizes the existing allocated bandwidth in the data transmission channel in a more efficient manner. Keyword: Bio-Medical Image, Medical Watermarking, Contour, Region Growing, HVS, Fragile watermark, Discrete Wavelet transform. Mathematics Subject Classification: 68U10, 65T60, 62P10, 92C50, 92C55. 1 Introduction Modern health care infrastructure is based on the Digital Information Management (DIM) in hospitals as well as Telemedical Information System (TIS). The main attributes of these systems are PACS (Picture Archiving and Communication System), HIN (Health information network), HIS (Hospital Information System), and its special cases of RIS (Radiology Information System) according to the DICOM (Digital Imaging and Communication in Medicine) standard [Coatrieux G. et al., 2000]. This Standard is a set of rules or protocols that allow medical information to be transmitted between instruments and computers of hospitals and users in network. Recently the advent of DIM has boosted the potential of telemedicine applications ranging from teleconsulting, telediagnosis etc. to cooperative working session and telesurgery [Zain J. M. et al., 2007]. This technology provides new ways for long-term storage in database, easy access and distribution of medical data. This introduces new practices for the professionals as well as the patient by accessing their own medical records known as Electronic Patient Records (EPR) for better diagnosis. The medical information records are complex set of clinical examinations, diagnosis annotations, other findings and images centered in its EPR. With these benefits there are parallel risks for EPR and strictly personal documents circulating International Journal of Tomography & Statistics, Summer 2010, Vol. 14, No. S10; Int. J. Tomogr. Stat., ISSN 0972-9976 ( Print ); ISSN 0973-7294 (Online) Copyright © 2010 by IJTS, ISDER www.ceser.res.in/ijts.html