Fast and efficient secured lossless coding of medical images-use of the lifting scheme

Lossless compression schemes with secure transmission play a key role in telemedicine applications that helps in accurate diagnosis and research. Traditional cryptographic algorithms for data security are not fast enough to process vast amount of data. Hence a novel secured lossless compression approach proposed in this paper is based on reversible integer wavelet transform, EZW algorithm arithmetic coding and selective bit scrambling. The use of the lifting scheme allows to generate truly lossless integer-to-integer wavelet transforms. Images are compressed/decompressed by well-known EZW algorithm and arithmetic coding is used to improve the compression performance and also increases the security level. The proposed approach employs scrambling method, which is fast, simple to implement, and it provides security. Lossless compression ratios and distortion performance of this proposed methods are found to be better than other lossless techniques.