RGB to Grayscale and RGB to XYZ using Reversible Logic Circuits

Color space conversion is a fundamental technique in image and video processing, enabling efficient storage, feature extraction, and compression. One of the most widely used transformations is RGB to grayscale conversion, which reduces data redundancy while maintaining critical image details. Another significant transformation is the RGB to XYZ conversion, which maps RGB values to a perceptually uniform color space, facilitating color management and ensuring consistency across different display devices. This paper presents a novel approach to color space conversion leveraging reversible logic gates, implementing both RGB to grayscale for BT.601 (SDTV)and RGB to XYZ transformations. Reversible logic has gained prominence as an energy-efficient computational paradigm, as it minimizes power dissipation by preventing information loss. The proposed reversible circuits are analyzed in terms of Gate Count (GC), Ancilla Inputs (AI), Garbage Outputs (GO), and Quantum Cost (QC), providing insights into their efficiency for low-power applications. The effectiveness of the proposed color space conversion schemes is further validated using performance metrics such as Mean Error Distance (MED), Mean Relative Error Distance (MRED), and Normalized Error Distance (NED). Given its compliance with established color conversion standards and its potential for integration into power-sensitive image and video processing systems, the proposed methodology presents a compelling alternative to conventional irreversible logic-based designs.