PILOT: A Pixel Intensity Driven Illuminant Color Estimation Framework for Color Constancy

In this study, a CNN based Pixel Intensity driven iLluminant cOlor esTimation framework, PILOT, is proposed. The framework consists of a local illuminant estimation module and an illuminant uncertainty prediction module, obtained using a 3-phase training approach. The network with the well-designed microarchitecture of distillation building block and the macroarchitecture of bifurcated organization is of great representational capacity and efficacy for color-relevant vision tasks, which helps obtain a >20% relative improvement over prior algorithms and achieve state-of-the-art accuracy of illuminant estimation on benchmark datasets. The proposed framework is also computationally efficient and parameter-economic, making it suitable for applications deployed on mobile platforms. The great interpretability also makes PILOT possible to serve as a guidance for designing statistics-based models for those low-end devices with tight budgets of power consumption and computational capacity.