Experimental and simulation orthogonal ghost imaging for measurement-domain optical steganography.

We present an experimentally validated measurement-domain steganography framework based on orthogonal ghost imaging (OGI). In the proposed scheme, a compact single-pixel OGI front-end with orthogonal illumination patterns generates the cover measurements, while a hash-initialized logistic map drives a chaotic keystream that is embedded in the least significant bits (LSBs) of the bucket intensities. This integration into a single optical-digital pipeline avoids holographic components, deep-learning-based reconstruction, and multi-channel architectures, and keeps both the hardware and computational complexity moderate enough for resource-constrained optical platforms. A combination of numerical simulations and single-pixel optical experiments shows that the framework supports imperceptible embedding with stable statistical behaviour. Under the reported operating conditions, the stego ghost images retain PSNR values above 50 dB, SSIM exceeding 0.996, and NPCR close to 99.98%, while intensity histograms, pixel correlations, higher-order moments, and chi-square statistics of the LSB plane remain almost unchanged. These results indicate that chaos-encrypted, bucket-domain LSB modulation can be effectively hidden within the speckle-like statistics and correlation-based reconstruction of OGI, allowing reliable message recovery without visible artifacts while exhibiting statistical consistency with basic steganalysis tests in the OGI domain. Overall, the proposed approach provides a proof-of-concept route to measurement-domain information hiding with hardware-generated covers. Owing to the use of a compact single-pixel architecture and lightweight digital processing, the framework suggests potential relevance to optical scenarios in which system complexity and processing resources are constrained. These considerations are based on architectural simplicity rather than measured power, volume, or embedded runtime metrics. A full system-level implementation and experimental validation on specific embedded or mobile platforms remain beyond the scope of this work and are left for future investigation.