Dielectron production in reactions $pi^- p rightarrow n e^+e^-$ and $pi^- p rightarrow n e^+e^- gamma$ at energies less than 1 GeV is studied assuming electron-positron pair production to occur in the virtual time-like photon splitting process. Theoretical predictions of the effective mass distribution of dielectrons and their angular dependence are presented. Extraction of the electromagnetic form factor of baryon transition in the time-like region from future experiments of the HADES Collaboration is discussed.