 VAE have been criticized because they generate blurry images.However, researchers employing this model were showing only the mean of the distributions, formula_73, rather than a sample of the learned Gaussian distribution

These samples were shown to be overly noisy due to the choice of a factorized Gaussian distribution.Employing a Gaussian distribution with a full covariance matrix,

could solve this issue, but is computationally intractable and numerically unstable, as it requires estimating a covariance matrix from a single data sample.