aa prefilter for damaged line art

from math import log2

def unsharp(clip, radius=1, strength=log2(3), custom=None):
    if callable(custom):
        return clip.std.MergeDiff(clip.std.MakeDiff(custom(clip)))

    strength = max(1e-6, min(strength, log2(3)))

    weight = 0.5 ** strength / ((1 - 0.5 ** strength) / 2)

    # find matrix with least rounding error when using integer clips
    if clip.format.sample_type == 0:
        all_matrices = [[x] for x in range(1, 1024)]
        for x in range(1023):
            while len(all_matrices[x]) < radius * 2 + 1:
                all_matrices[x].append(all_matrices[x][-1] / weight)
        error = [sum([abs(x - round(x)) for x in matrix[1:]]) for matrix in all_matrices]
        matrix = [round(x) for x in all_matrices[error.index(min(error))]]
    else:
        matrix = [1]
        while len(matrix) < radius * 2 + 1:
            matrix.append(matrix[-1] / weight)

    matrix = [matrix[x] for x in [(2,1,2,1,0,1,2,1,2), (4,3,2,3,4,3,2,1,2,3,2,1,0,1,2,3,2,1,2,3,4,3,2,3,4)][radius-1]]

    return clip.std.MergeDiff(clip.std.MakeDiff(clip.std.Convolution(matrix)))



y = depth(get_y(clip), 16)
y0=y

clips = [y, y.znedi3.nnedi3(1), y.znedi3.nnedi3(0)]

s = unsharp(y, radius=1, strength=log2(3))

out = core.std.Expr([s]+clips, 'x y z a max max min y z a min min max')

y = out.std.Transpose()

clips = [y, y.znedi3.nnedi3(1), y.znedi3.nnedi3(0)]

s = unsharp(y, radius=1, strength=log2(3))

out = core.std.Expr([s]+clips, 'x y z a max max min y z a min min max').std.Transpose()

core.std.Interleave(y0, out).set_output()




""" dunno what went wrong here but dont wanna delete it
import math

def unsharp(clip, radius=1, strength=math.log2(3), custom=None):
    if callable(custom):
        return clip.std.MergeDiff(clip.std.MakeDiff(custom(clip)))

    strength = max(1e-6, min(strength, math.log2(3)))

    weight = 0.5 ** strength / ((1 - 0.5 ** strength) / 2)

    # find matrix with least rounding error when using integer clips
    if clip.format.sample_type == 0:
        all_matrices = [[x] for x in range(1, 1024)]
        for x in range(1023):
            while len(all_matrices[x]) < radius * 2 + 1:
                all_matrices[x].append(all_matrices[x][-1] / weight)
        error = [sum([abs(x - round(x)) for x in matrix[1:]]) for matrix in all_matrices]
        matrix = [round(x) for x in all_matrices[error.index(min(error))]]
    else:
        matrix = [1]
        while len(matrix) < radius * 2 + 1:
            matrix.append(matrix[-1] / weight)

    matrix = [matrix[x] for x in [(2,1,2,1,0,1,2,1,2), (4,3,2,3,4,3,2,1,2,3,2,1,0,1,2,3,2,1,2,3,4,3,2,3,4)][radius-1]]

    return clip.std.MergeDiff(clip.std.MakeDiff(clip.std.Convolution(matrix)))

def pre_aa(clip, radius=1, strength=math.log2(3), pp=None, **nnedi3_params):

    sharp = unsharp(clip, radius=radius, strength=strength)

    nedi = clip.znedi3.nnedi3(3, **nnedi3_params).std.SeparateFields(True).std.SelectEvery(4, [0, 3]).std.DoubleWeave()[::2]

    if callable(pp):
        nedi = pp(nedi)

    clip = core.std.Expr([sharp, clip, nedi], 'x y z max min y z min max').std.Transpose()

    sharp = unsharp(clip, radius=radius, strength=strength)

    nedi = clip.znedi3.nnedi3(3, **nnedi3_params).std.SeparateFields(True).std.SelectEvery(4, [0, 3]).std.DoubleWeave()[::2]

    if callable(pp):
        nedi = pp(nedi)

    return core.std.Expr([sharp, clip, nedi], 'x y z max min y z min max').std.Transpose()
"""