function TASBlend(clip c, float "ratio")  {
        # reduces framerate to 1/2 but leaves flicker effects partly visible
        # blends frame pairs with alternating opacity (default is 2/3+1/3;1/3+2/3)
        # optional "ratio" is the opacity of the first frame out of the four
        ratio    = default(ratio, 2.0 / 3)
        opacity1 = round((1 - ratio) * 257)
        opacity2 = round((    ratio) * 257)
        c
        Interleave(Layer(SelectEvery(4, 0), SelectEvery(4, 1), level=opacity1),
        \          Layer(SelectEvery(4, 2), SelectEvery(4, 3), level=opacity2))
}

AVISource("60_fps_avi_dump_thing_from_snes9x.avi")

TASBlend