  Certification of nonlocality of quantum mechanics is an important fundamental
test that typically requires prolonged data collection and is only revealed in
an in-depth analysis. These features are often particularly exposed in hybrid
systems, such as interfaces between light and atomic ensembles. Certification
of entanglement from images acquired with single-photon camera can mitigate
this issue by exploiting multiplexed photon generation. Here we demonstrate
this feature in a quantum memory (QM) operating in a real-time feedback mode.
Through spatially-multimode spin-wave storage the QM enables operation of the
real-time ghost imaging (GI) protocol. By properly preparing the spatial phase
of light emitted by the atoms we enable observation of Bell-type nonlocality
from a single image acquired in the far field as witnessed by the Bell
parameter of $S=2.227\pm0.007>2$. Our results are an important step towards
fast and efficient utilization of multimode quantum memories both in protocols
and in fundamental tests.
