get_w

[deadnews]

"""
https://github.com/HomeOfVapourSynthEvolution/havsfunc/blob/master/havsfunc.py#L5907
"""
import math


def cround(x):
    return math.floor(x + 0.5) if x > 0 else math.ceil(x - 0.5)


def m4(x):
    return 16 if x < 16 else cround(x / 4) * 4


desc_w = m4(849 * 1920 / 1080)
print(f'havsfunc:   {desc_w}')


"""
https://github.com/Infiziert90/getnative/blob/master/getnative/app.py#L194
"""
def getw(h, only_even=True):
    w = h * 16 / 9
    w = int(round(w))
    if only_even:
        w = w // 2 * 2
    return w


desc_w = getw(849)
print(f'getnative:  {desc_w}')


"""
https://github.com/Irrational-Encoding-Wizardry/kagefunc/blob/master/kagefunc.py#L336
"""
def getw(height, aspect_ratio=16 / 9, only_even=True):
    """
    Returns width for image.
    """
    width = height * aspect_ratio
    width = int(round(width))
    return width // 2 * 2 if only_even else width


desc_w = getw(849)
print(f'kagefunc:   {desc_w}')


"""
https://github.com/Irrational-Encoding-Wizardry/vsutil/blob/master/vsutil/info.py#L74
"""
def get_w(height: int, aspect_ratio: float = 16 / 9, *, only_even: bool = True) -> int:
    """
    Calculates the width for a clip with the given height and aspect ratio.
    only_even is True by default because it imitates the math behind most standard resolutions (e.g. 854x480).
    """
    width = height * aspect_ratio
    if only_even:
        return round(width / 2) * 2
    return round(width)


desc_w = get_w(849)
print(f'vsutil:     {desc_w}')

↓

havsfunc:   1508
getnative:  1508
kagefunc:   1508
vsutil:     1510

[OrangeChannel]

Well, 849*16/9 == 849*1920/1080 == 1509.3333333333333 ~= Fraction(4528, 3) so vsutil is actually the only one doing this correctly if we're to assume we round to nearest even :laughing: . Raise the issue in the other three repo's unless for some reason this is meant to be rounded down.

EDIT: reason would seem to be looking for a mod4 resolution (maybe subsampling concerns), which I guess we could implement as another param in get_w but I don't see the point since 849 is not mod4/mod2 either.