[en] The previous dilepton spectrum expression and relativistic hydrodynamic equations derived from the energy-momentum conservation, are generalized to include the effect of the space-time distribution of particles. The influences of the particle distribution and the latent heat released by the phase transition on the dilepton spectrum are studied on the basis of the generalized formalism. We find that these two influences significantly change the characteristic dilepton spectrum for the formation of quark matter given by previous authors, they especially cause the non-monotony of the total dilepton yield with respect to the initial temperature. It is shown that these two influences must be included in order to get a more reasonable characteristic dilepton spectrum for the formation of the quark matter. (orig.)