ops.py

# From https://github.com/DeepVoltaire/AutoAugment

from PIL import Image, ImageEnhance, ImageOps
import random


class ShearX(object):
    def __init__(self, fillcolor=(128, 128, 128)):
        self.fillcolor = fillcolor

    def __call__(self, x, magnitude):
        return x.transform(
            x.size, Image.AFFINE, (1, magnitude * random.choice([-1, 1]), 0, 0, 1, 0),
            Image.BICUBIC, fillcolor=self.fillcolor)


class ShearY(object):
    def __init__(self, fillcolor=(128, 128, 128)):
        self.fillcolor = fillcolor

    def __call__(self, x, magnitude):
        return x.transform(
            x.size, Image.AFFINE, (1, 0, 0, magnitude * random.choice([-1, 1]), 1, 0),
            Image.BICUBIC, fillcolor=self.fillcolor)


class TranslateX(object):
    def __init__(self, fillcolor=(128, 128, 128)):
        self.fillcolor = fillcolor

    def __call__(self, x, magnitude):
        return x.transform(
            x.size, Image.AFFINE, (1, 0, magnitude * x.size[0] * random.choice([-1, 1]), 0, 1, 0),
            fillcolor=self.fillcolor)


class TranslateY(object):
    def __init__(self, fillcolor=(128, 128, 128)):
        self.fillcolor = fillcolor

    def __call__(self, x, magnitude):
        return x.transform(
            x.size, Image.AFFINE, (1, 0, 0, 0, 1, magnitude * x.size[1] * random.choice([-1, 1])),
            fillcolor=self.fillcolor)


class Rotate(object):
    # from https://stackoverflow.com/questions/
    # 5252170/specify-image-filling-color-when-rotating-in-python-with-pil-and-setting-expand
    def __call__(self, x, magnitude):
        rot = x.convert("RGBA").rotate(magnitude)
        return Image.composite(rot, Image.new("RGBA", rot.size, (128,) * 4), rot).convert(x.mode)


class Color(object):
    def __call__(self, x, magnitude):
        return ImageEnhance.Color(x).enhance(1 + magnitude * random.choice([-1, 1]))


class Posterize(object):
    def __call__(self, x, magnitude):
        return ImageOps.posterize(x, magnitude)


class Solarize(object):
    def __call__(self, x, magnitude):
        return ImageOps.solarize(x, magnitude)


class Contrast(object):
    def __call__(self, x, magnitude):
        return ImageEnhance.Contrast(x).enhance(1 + magnitude * random.choice([-1, 1]))


class Sharpness(object):
    def __call__(self, x, magnitude):
        return ImageEnhance.Sharpness(x).enhance(1 + magnitude * random.choice([-1, 1]))


class Brightness(object):
    def __call__(self, x, magnitude):
        return ImageEnhance.Brightness(x).enhance(1 + magnitude * random.choice([-1, 1]))


class AutoContrast(object):
    def __call__(self, x, magnitude):
        return ImageOps.autocontrast(x)


class Equalize(object):
    def __call__(self, x, magnitude):
        return ImageOps.equalize(x)


class Invert(object):
    def __call__(self, x, magnitude):
        return ImageOps.invert(x)