JIP_V2_N2_RP6 Archana Tiwari Manisha Sharma Journal on Image Processing 2349-6827 2 2 32 37 Image Authentication, Semifragile Watermark, Watermark Embedding, Vector Quantization, Blind Extraction In this paper, a new technique for image authentication is presented which uses semifragile watermarking scheme using vector quantization approach. The proposed scheme suggests semifragile watermarking scheme for blind image authentication using VQ (Vector quantization) by applying novel index based method combined with Discrete cosine transform. Present method is tested using, different combinations of code books for watermark insertion and extraction procedure . The proposed method results in an improved PSNR with an average value of 42 dB compared to average value 30 dB suggested by Lu et al. April - June 2015 Copyright © 2015 i-manager publications. All rights reserved. i-manager Publications http://www.imanagerpublications.com/Article.aspx?ArticleId=3405