A priori on the hyperparameters
To obtain the unicity of the optimal coupleA model with higher order derivatives
We could estimate not only but also . Currently must be fixed, because of the existence of an infinity of local maxima of the likelihood (one for each ).
For a best quality image reconstructionTowards a more local approach : adaptive and parameters
Too global approach with only one couple for a large size image.
Results depend on the choice of an estimation area : see example.