VAR_PREV_SELECTED_T  206 libavfilter/f_select.c     select->var_values[VAR_PREV_SELECTED_T]   = NAN;
VAR_PREV_SELECTED_T  357 libavfilter/f_select.c         select->var_values[VAR_PREV_SELECTED_T]   = select->var_values[VAR_T];