A stereo 3D video frame includes left and right components that are combined to produce a stereo image. For a given amount of distortion, the left and right components may have different impacts on perceptual visual quality of the stereo image due to asymmetry in the distortion response of the human eye. A 3D video encoder adjusts an allocation of coding bits between left and right components of the 3D video based on a frame-level bit budget and a weighting between the left and right components. The video encoder may generate the bit allocation in the rho (ρ) domain. The weighted bit allocation may be derived based on a quality metric that indicates overall quality produced by the left and right components. The weighted bit allocation compensates for the asymmetric distortion response to reduce overall perceptual distortion in the stereo image and thereby enhance or maintain visual quality.