The resonance parameters of the collinear H + H-2 system, calculated recently by the Lorentzian fit of Fourier spectra of the semiclassical time correlation function C(t), are here extracted directly by harmonic inversion of C(t) using the filter-diagonalization technique. The new approach reveals more resonances from a much shorter segment of the same signal C(t). This reduces both the semiclassical error and the overall numerical effort. (C) 1997 Elsevier Science B.V.