Disclosed are techniques for video stream compression. A motion predicted frame and a current frame of video data are converted from a source color space to a perceptual color space. A delta (Δ) frame is calculated between the current frame and the motion predicted frame. Input color difference values between the current frame and the motion predicted frame are determined and mapped to a normalized output to create a tone mapped color difference image. The tone mapped color difference image and Δ frame are multiplied to obtain a weighted Δ frame. Δ loss is calculated as the difference between the weighted Δ frame and the Δ frame. A variance map of the motion predicted frame is multiplied by the Δ loss to obtain a Δ preservation map. The weighted Δ frame and Δ preservation map are summed to obtain a modified Δ frame which may be transformed, quantized and encoded.
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