Lossless coding of video sequences is becoming increasingly attractive for applications as diverse as digital cinema, medical imaging and professional video processing. We present a new low-delay, low-complexity algorithm for lossless color video compression. The proposed technique adaptively exploits temporal, spatial and spectral redundancy. Key features of the coder are a backward-adaptive temporal predictor, an intra-frame spatial predictor and adaptive optimal weighting of both predictive components. The residual error is entropy coded by a context-based arithmetic encoder. The proposed lossless video encoder delivers significantly higher compression gains than traditional approaches at approximately the same complexity and delay, enabling efficient storage and communications for emerging lossless video applications.