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We analyse the pion electromagnetic, charged-current, and $\pi\gamma$transition form factors at timelike momentum transfers $q$, $q^2=s\le 1.4$GeV$^2$, using a dispersion approach. We discuss in detail the propagatormatrix of the photon-vector-meson system and define certain reduced amplitudes,or vertex functions, describing the coupling of this system to final states. Wethen apply the derived analytic expressions to the analysis of the recent$e^+e^-\to \pi^+\pi^-$, $\tau^-\to \pi^-\pi^0\nu_\tau$, and $e^+e^-\to\pi^0\gamma$ data. We find the reduced amplitudes for the coupling of thephoton and vector mesons to two pseudoscalars to be constant, independent of$s$, in the range considered, indicating a "freezing" of the amplitudes for$s\le 1$ GeV. The fit to the form factor data leads to the following values ofthe Breit-Wigner resonance masses m_{\rho^-}=775.3\pm 0.8 MeV,m_{\rho^0}=773.7\pm 0.6 MeV and m_\omega=782.43\pm 0.05 MeV, where the errorsare only statistical.Comment: revtex, 23 page

Masses and couplings of vector mesonsfrom the pion electromagnetic, weak, and $\pi\gamma$ transition form factors