Protection of bio medical iris image using watermarking and cryptography with WPT

•The proposed method provides double layer security in the biometric systems.•The image of iris is obtained from the Iris scanning device and it is divided by the use of WPT.•The proposed work has been implemented in MATLAB 2017b. The emerging technologies in this present world is real time biometrics which recognized a specific person in a reliable manner through their distinct biological features. The most reliable biometric identification is an iris identification. The collection of iris images can be stored in the database which is hacked by the intruders. In order to prevent these databases with watermark text, a novel hybrid method is proposed which is a combination of Wavelet Packet Transform (WPT) and cryptography. This paper presents WPT for segmenting the iris image and finding the minimum energy band where the watermark text is embedded. The watermark text is the personal information of the owner of iris. Once the watermarking is done, the cryptographic key is used to encrypt the watermarked image. This way, both the image and the watermark text are prevented in an efficient manner. The quality measures of watermarked image have been analyzed and compared with other existing techniques. The proposed technique has been analyzed with blurring, salt and pepper, JPEG, cropping, Gaussian noise, rotate, speckle noise, filter, gamma, intensity and histogram equalization noises having PSNR value increased by 3.3%, 3.6%, 4.1%, 5.3%, 7.7%, 6.1%, 11.9%, 7.7%, 14.4%, 10.7% and 10.2% respectively which effectively increased the quality of image.