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limit

Functions:

  • limit_filter –

    Performs a soft-limiting between two clips to limit the difference of filtering while avoiding artifacts.

limit_filter 

limit_filter(
    flt: VideoNode,
    src: VideoNode,
    ref: VideoNode | None = None,
    dark_thr: float | Sequence[float] = 1.0,
    bright_thr: float | Sequence[float] = 1.0,
    elast: float | Sequence[float] = 2.0,
    planes: PlanesT = None,
) -> VideoNode

Performs a soft-limiting between two clips to limit the difference of filtering while avoiding artifacts.

Parameters:

  • flt

    (VideoNode) –

    Filtered clip.

  • src

    (VideoNode) –

    Source clip.

  • ref

    (VideoNode | None, default: None ) –

    Reference clip, to compute the weight to be applied on filtering diff.

  • dark_thr

    (float | Sequence[float], default: 1.0 ) –

    Threshold (8-bit scale) to limit dark filtering diff.

  • bright_thr

    (float | Sequence[float], default: 1.0 ) –

    Threshold (8-bit scale) to limit bright filtering diff.

  • elast

    (float | Sequence[float], default: 2.0 ) –

    Elasticity of the soft threshold.

  • planes

    (PlanesT, default: None ) –

    Planes to process. Defaults to all.

Returns:

  • VideoNode –

    Limited clip.

Source code 
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def limit_filter(
    flt: vs.VideoNode,
    src: vs.VideoNode,
    ref: vs.VideoNode | None = None,
    dark_thr: float | Sequence[float] = 1.0,
    bright_thr: float | Sequence[float] = 1.0,
    elast: float | Sequence[float] = 2.0,
    planes: PlanesT = None,
) -> vs.VideoNode:
    """
    Performs a soft-limiting between two clips to limit the difference of filtering while avoiding artifacts.

    Args:
        flt: Filtered clip.
        src: Source clip.
        ref: Reference clip, to compute the weight to be applied on filtering diff.
        dark_thr: Threshold (8-bit scale) to limit dark filtering diff.
        bright_thr: Threshold (8-bit scale) to limit bright filtering diff.
        elast: Elasticity of the soft threshold.
        planes: Planes to process. Defaults to all.

    Returns:
        Limited clip.
    """
    ref = fallback(ref, src)

    base_expr = "x y - DIFF! x z - abs DIFF_REF_ABS!"
    dark_expr = (
        "{dark_thr} {elast} * THR! 1 THR@ {dark_thr} - / SLOPE! "
        "DIFF_REF_ABS@ {dark_thr} <= x DIFF_REF_ABS@ THR@ >= y "
        "y DIFF@ THR@ DIFF_REF_ABS@ - * SLOPE@ * + ? ?"
    )
    bright_expr = dark_expr.replace("dark_thr", "bright_thr")

    return norm_expr(
        [flt, src, ref],
        f"{base_expr} x z < {dark_expr} {bright_expr} ?",
        dark_thr=[scale_delta(x, 8, flt) for x in to_arr(dark_thr)],
        bright_thr=[scale_delta(x, 8, flt) for x in to_arr(bright_thr)],
        elast=elast,
        planes=planes,
    )