Hiding patient information in medical images: an enhanced dual image separable reversible data hiding algorithm for E-healthcare

E-healthcare requires communication of patient report to a specialized doctor in a real time scenario. Therefore, any harm to patient medical data can lead to a faulty diagnosis that can be lethal for the patient. To ensure safe and secure communication in E-healthcare framework, a high capacity dual image separable reversible data hiding algorithm in the encrypted domain has been presented in this paper. All compared reversible data hiding techniques have been shown predominant outcomes, yet just on natural images not on medical images because underflow problem may arise in medical images due to a large number of pixels have low-intensity values. Thus, an enhanced separable reversible data hiding technique in the encrypted domain has been introduced here that gives a higher embedding rate than all the looked at reversible data hiding techniques by embedding $$log_2(u-l+1)$$ binary bits of patient information at non-seed pixels of the cover image without any occurrence of underflow and overflow problem so that empowering it to embed and recover information precisely from low-intensity pixels too. This property makes our proposed methodology truly reasonable for its utilization on medical images. For authentication analysis of electronic patient information (EPI) at the recipient end, a fragile watermark has also been embedded with EPI respectively. For all test images, embedding rate of 2.38 bits per pixel (bpp) with an average PSNR value is 41.05 dB is observed which demonstrates that the proposed method is capable of giving good quality stego images even at high payload also.