utils ¶

def get_field_difference(
    clip: vs.VideoNode, tff: FieldBasedLike | bool | None = None, func: FuncExcept | None = None
) -> ConstantFormatVideoNode:
    """
    Compute the difference between top and bottom fields in a clip.

    Args:
        clip: Input clip.
        tff: Field order (top-field-first). If None, inferred from the clip. Defaults to None.
        func: Function returned for custom error handling. This should only be set by VS package developers.

    Returns:
        A clip with a per-frame property "FieldDifference" indicating the absolute difference between fields.
    """
    func = func or get_field_difference

    assert check_variable(clip, func)

    tff = FieldBased.from_param_or_video(tff, clip, True, func).is_tff

    stats = clip.std.SeparateFields(tff).std.PlaneStats()

    return core.akarin.PropExpr(
        [clip, stats[::2], stats[1::2]], lambda: {"FieldDifference": "y.PlaneStatsAverage z.PlaneStatsAverage - abs"}
    )

def reinterlace(
    clip: vs.VideoNode, tff: FieldBasedLike | bool | None = None, func: FuncExcept | None = None
) -> ConstantFormatVideoNode:
    """
    Reinterlace a progressive clip by separating and weaving fields.

    Args:
        clip: Input clip.
        tff: Field order (top-field-first). If None, inferred from the clip. Defaults to None.
        func: Function returned for custom error handling. This should only be set by VS package developers.

    Returns:
        A reinterlaced clip with fields woven back into interlaced frames.
    """
    func = func or reinterlace

    assert check_variable(clip, func)

    tff = FieldBased.from_param_or_video(tff, clip, True, func).is_tff

    return weave(clip.std.SeparateFields(tff).std.SelectEvery(4, (0, 3)), tff, func)

def reweave(
    clipa: vs.VideoNode, clipb: vs.VideoNode, tff: FieldBasedLike | bool | None = None, func: FuncExcept | None = None
) -> ConstantFormatVideoNode:
    """
    Interleave two clips and weave them into full frames.

    Args:
        clipa: First input clip.
        clipb: Second input clip.
        tff: Field order (top-field-first). If None, inferred from the clip. Defaults to None.
        func: Function returned for custom error handling. This should only be set by VS package developers.

    Returns:
        A reweaved clip with fields combined into frames.
    """
    func = func or reweave
    assert check_variable(clipa, func)
    assert check_variable(clipb, func)

    return weave(core.std.Interleave([clipa, clipb]), tff, func)

def telecine_patterns(
    clipa: vs.VideoNode, clipb: vs.VideoNode, length: int = 5, func: FuncExcept | None = None
) -> list[ConstantFormatVideoNode]:
    """
    Generate all possible telecine patterns by interleaving frames from two clips.

    Args:
        clipa: First input clip.
        clipb: Second input clip.
        length: Cycle length used for frame selection. Defaults to 5.
        func: Function returned for custom error handling. This should only be set by VS package developers.

    Returns:
        A list of interleaved clips, each representing a unique telecine pattern.
    """
    func = func or telecine_patterns

    assert check_variable(clipa, func)
    assert check_variable(clipb, func)

    a_select = [clipa.std.SelectEvery(length, i) for i in range(length)]
    b_select = [clipb.std.SelectEvery(length, i) for i in range(length)]

    return [core.std.Interleave([(b_select if i == j else a_select)[j] for j in range(length)]) for i in range(length)]

def weave(
    clip: vs.VideoNode, tff: FieldBasedLike | bool | None = None, func: FuncExcept | None = None
) -> ConstantFormatVideoNode:
    """
    Recombine fields into frames using DoubleWeave.

    Args:
        clip: Input clip.
        tff: Field order (top-field-first). If None, inferred from the clip. Defaults to None.
        func: Function returned for custom error handling. This should only be set by VS package developers.

    Returns:
        A clip with fields woven back into full frames.
    """
    func = func or weave

    assert check_variable(clip, func)

    tff = FieldBased.from_param_or_video(tff, clip, True, func).is_tff

    return clip.std.DoubleWeave(tff)[::2]