dvd_deblur.py

class LowpassType(Enum):
    Test1 = 0
    """Two horizontal 1x resamples, for DVDs"""

    Test2 = 1
    """One 1x resample in both directions, for BDs"""


class FmtConvLanczos(vskernels.FmtConv):
    _kernel = "lanczos"


def dvd_deblur(
    clip: vs.VideoNode,
    clean: vs.VideoNode,
    method: Enum,
    blur: float | tuple[float, float],
    taps: int = 4,
    postfilter: vstools.GenericVSFunction = None,
    draft: bool = False,
) -> vs.VideoNode:

    lpf = FmtConvLanczos(taps)

    if method == LowpassType(0):
        mangle = lpf.scale(clean, clip.width, clip.height, fh=1 / blur[0])
        mangle = lpf.scale(mangle, clip.width, clip.height, fh=1 / blur[1])
    elif method == LowpassType(1):
        mangle = lpf.scale(clean, clip.width, clip.height, fh=1 / blur, fv=1 / blur)

    diff = core.std.MakeDiff(clean, mangle)
    if draft:
        return (mangle, diff)
    if postfilter:
        clip = postfilter((clip, mangle))
    return core.std.MergeDiff(clip, diff)

Clever!