SEMI-FRAGILE BLIND WATERMARKING MECHANISM FOR COLOR IMAGE AUTHENTICATION AND TAMPERING

Abstract

Digital Image watermarking data hiding technique is proposed in paper to provide authentication to color image. It has capability of tamper detection and tamper localization. The suggested system is blind watermarking system which doesn’t require original information at destination. The system is robust against non-malicious attacks where as fragile with malicious attacks. The watermark is generated based on content of original image and it is embedded using IWT and QIM techniques. To the destination place for authentication purpose, embedded watermark is extracted. For classification of image, extracted and generated watermark from watermarked image are compared and based on this differential information, tampering is analyzed. The image is classified as authentic or tampered as per clustering of pixels within differential information. If image is declared as tampered then tampered region is identified using clustering detail. The PSNR is achieved up to 43.57dB and NCC is near to 1. As per numbers of parameters concern and as per experiments, it is found that proposed system is the improved version of existing systems.

Keywords

• image watermarking
• image authentication
• tamper detection
• tamper localization