Fractionalization is a phenomenon where an elementary excitation partitions into several pieces. This picture explains non-trivial transport through a junction of one-dimensional edge channels defined by topologically distinct quantum Hall states, for example, a hole-conjugate state at Landau-level filling factor $ u$ = 2/3. Here we employ a time-resolved scheme to identify an elementary fractionalization process; injection of charge q from a non-interaction region into an interacting and scattering region of one-dimensional channels results in the formation of a collective excitation with charge $(1-textit{r})textit{q}$ by reflecting fractionalized charge $textit{rq}$. The fractionalization factors, $textit{r}$ = 0.34$pm$0.03 for $ u$ = 2/3 and $textit{r}$ = 0.49$pm$0.03 for $ u$ = 2, are consistent with the quantized values of 1/3 and 1/2, respectively, which are expected in the disorder dominated regime. The scheme can be used for generating and transporting fractionalized charges with a well-defined time course along a well-defined path.