A novel fused coupled chaotic map based confidential data embedding-then-encryption of electrocardiogram signal

Abstract

In telecardiology applications, research has been underway to protect the patient's confidential information from unauthorized access using Electrocardiogram (ECG) steganography or encryption approaches. A novel Fused Coupled Chaotic Map (FCCM) structure based integrated embedding-then-encryption approach is proposed for patient's confidential data embedding in ECG and its subsequent encryption. The proposed ECG embedding-then-encryption algorithm consists of four phases: confidential data ciphering, LSB embedding, substitution, and permutation. Four FCCMs under different initial conditions and control parameters undergoes level shifting or sorting based quantization. The updation of control parameters made to be ECG content aware of security enhancement. The generated {FCCMi,: i∈(1–4)} are applied to (i) cipher confidential data, (ii) craft the embedding locations to hide segmented-ciphered confidential data, (iii) substitution and (iv) permutation processes for data embedding-then-encryption of ECG. The performance of the proposed method was evaluated over MIT-BIH Arrhythmia and self-recorded ECG (lead-II) database. The test suites NIST-800 and 0-1 are employed to check randomness of chaotic sequences. The PRD, PRDN, PRD1024, RMS, SNR, PSNR, WWPRD, WEDD, and BERs were 0.04, 1.05, 0.75, 5.55×10−4, 41.21, 70.17, 3.02×10−2, 5.91×10−3, and 0.00 for MIT-BIH Arrhythmia ECG database (Lead-II) at payload 2.4Kb. Performance measures for Self-recorded dataset are 0.04, 2.62, 2.62, 5.49×10−4, 32.16, 68.72, 9.36×10−2, 1.93×10−2, and 0.00 respectively. Experimental results, security analysis and comparison with existing state-of-art methods prove the effectiveness of the proposed approach for assured patient's confidential data security. Furthermore, the efficiency of the proposed approach has also been evaluated on compressed ECG.