Novel Integer Hahn Transform for Real-Time Lossless Image Authentication in IoT: A 32-Bit Microcontroller Implementation

Traditional discrete orthogonal transforms often introduce reconstruction errors, hindering their use in digital signal processing applications requiring exact signal recovery. To overcome this limitation, this paper presents the discrete integer Hahn transform (IHT), a novel discrete integer-based transform designed for lossless signal processing on resource-constrained platforms. By combining the IHT with a multiparametric 1D chaotic system, we develop a new lossless watermarking scheme for real-time image authentication and tamper detection. This scheme excels in several key areas: perfect watermark retrieval, minimal computational overhead suitable for embedded systems, wireless compatibility, and strong security guarantees. We validate our approach on a low-cost, resource-constrained embedded system based on the RP2040 32-bit microcontroller and demonstrate superior efficiency compared to recent state-of-the-art methods, especially in constrained environments. These findings underscore the potential of our technique for securing wireless image communication on resource-limited Internet of Things (IoT) devices.