We address the problem of reconstructing a set of K binary patterns \(\varvec{\Xi }= (\varvec{\xi }^1,..., \varvec{\xi }^K) \in \{-1, +1 \}^{N \times K}\) , starting from their covariance matrix \(\varvec{\Xi }\varvec{\Xi }^T\) and from a set of mixtures of the form \(\varvec{\sigma }_M= \text {sign}(\sum _{\mu \in \mathcal {S}_M \subseteq \{1,..., K\}} \varvec{\xi }^{\mu })\) , with \(\left\lvert S_M\right\rvert =M\) . To this aim, we engage a modular Hebbian network, specified by the interaction matrix \(\varvec{J}^H = \frac{1}{N}\varvec{\Xi }\varvec{\Xi }^T\) , where \({\varvec{\sigma }_M}\) is taken as the initial state, repeated in each of the constituting L modules and the stable state resulting from a Gibbs evolution rule is taken as an L-tuple of candidate patterns. Finally, by properly handling \(\varvec{J}^H\) we can derive the projector matrix \(\varvec{J}^K = \varvec{\Xi }(\varvec{\Xi }^T \varvec{\Xi })^{-1} \varvec{\Xi }^T\) by which we can determine whether these candidate patterns are a good estimate for the ground patterns.