Merge pull request #33 from rwightman/autoaugment

Add AutoAugment ImageNet policies for training

Author: rwightman

timm/data/auto_augment.py

@@ -0,0 +1,360 @@
+""" Auto Augment
+Implementation adapted from:
+    https://github.com/tensorflow/tpu/blob/master/models/official/efficientnet/autoaugment.py
+Papers: https://arxiv.org/abs/1805.09501 and https://arxiv.org/abs/1906.11172
+
+Hacked together by Ross Wightman
+"""
+import random
+import math
+from PIL import Image, ImageOps, ImageEnhance
+import PIL
+import numpy as np
+
+
+_PIL_VER = tuple([int(x) for x in PIL.__version__.split('.')[:2]])
+
+_FILL = (128, 128, 128)
+
+# This signifies the max integer that the controller RNN could predict for the
+# augmentation scheme.
+_MAX_LEVEL = 10.
+
+_HPARAMS_DEFAULT = dict(
+    translate_const=250,
+    img_mean=_FILL,
+)
+
+_RANDOM_INTERPOLATION = (Image.NEAREST, Image.BILINEAR, Image.BICUBIC)
+
+
+def _interpolation(kwargs):
+    interpolation = kwargs.pop('resample', Image.NEAREST)
+    if isinstance(interpolation, (list, tuple)):
+        return random.choice(interpolation)
+    else:
+        return interpolation
+
+
+def _check_args_tf(kwargs):
+    if 'fillcolor' in kwargs and _PIL_VER < (5, 0):
+        kwargs.pop('fillcolor')
+    kwargs['resample'] = _interpolation(kwargs)
+
+
+def shear_x(img, factor, **kwargs):
+    _check_args_tf(kwargs)
+    return img.transform(img.size, Image.AFFINE, (1, factor, 0, 0, 1, 0), **kwargs)
+
+
+def shear_y(img, factor, **kwargs):
+    _check_args_tf(kwargs)
+    return img.transform(img.size, Image.AFFINE, (1, 0, 0, factor, 1, 0), **kwargs)
+
+
+def translate_x_rel(img, pct, **kwargs):
+    pixels = pct * img.size[0]
+    _check_args_tf(kwargs)
+    return img.transform(img.size, Image.AFFINE, (1, 0, pixels, 0, 1, 0), **kwargs)
+
+
+def translate_y_rel(img, pct, **kwargs):
+    pixels = pct * img.size[1]
+    _check_args_tf(kwargs)
+    return img.transform(img.size, Image.AFFINE, (1, 0, 0, 0, 1, pixels), **kwargs)
+
+
+def translate_x_abs(img, pixels, **kwargs):
+    _check_args_tf(kwargs)
+    return img.transform(img.size, Image.AFFINE, (1, 0, pixels, 0, 1, 0), **kwargs)
+
+
+def translate_y_abs(img, pixels, **kwargs):
+    _check_args_tf(kwargs)
+    return img.transform(img.size, Image.AFFINE, (1, 0, 0, 0, 1, pixels), **kwargs)
+
+
+def rotate(img, degrees, **kwargs):
+    _check_args_tf(kwargs)
+    if _PIL_VER >= (5, 2):
+        return img.rotate(degrees, **kwargs)
+    elif _PIL_VER >= (5, 0):
+        w, h = img.size
+        post_trans = (0, 0)
+        rotn_center = (w / 2.0, h / 2.0)
+        angle = -math.radians(degrees)
+        matrix = [
+            round(math.cos(angle), 15),
+            round(math.sin(angle), 15),
+            0.0,
+            round(-math.sin(angle), 15),
+            round(math.cos(angle), 15),
+            0.0,
+        ]
+
+        def transform(x, y, matrix):
+            (a, b, c, d, e, f) = matrix
+            return a * x + b * y + c, d * x + e * y + f
+
+        matrix[2], matrix[5] = transform(
+            -rotn_center[0] - post_trans[0], -rotn_center[1] - post_trans[1], matrix
+        )
+        matrix[2] += rotn_center[0]
+        matrix[5] += rotn_center[1]
+        return img.transform(img.size, Image.AFFINE, matrix, **kwargs)
+    else:
+        return img.rotate(degrees, resample=kwargs['resample'])
+
+
+def auto_contrast(img, **__):
+    return ImageOps.autocontrast(img)
+
+
+def invert(img, **__):
+    return ImageOps.invert(img)
+
+
+def equalize(img, **__):
+    return ImageOps.equalize(img)
+
+
+def solarize(img, thresh, **__):
+    return ImageOps.solarize(img, thresh)
+
+
+def solarize_add(img, add, thresh=128, **__):
+    lut = []
+    for i in range(256):
+        if i < thresh:
+            lut.append(min(255, i + add))
+        else:
+            lut.append(i)
+    if img.mode in ("L", "RGB"):
+        if img.mode == "RGB" and len(lut) == 256:
+            lut = lut + lut + lut
+        return img.point(lut)
+    else:
+        return img
+
+
+def posterize(img, bits_to_keep, **__):
+    if bits_to_keep >= 8:
+        return img
+    bits_to_keep = max(1, bits_to_keep)  # prevent all 0 images
+    return ImageOps.posterize(img, bits_to_keep)
+
+
+def contrast(img, factor, **__):
+    return ImageEnhance.Contrast(img).enhance(factor)
+
+
+def color(img, factor, **__):
+    return ImageEnhance.Color(img).enhance(factor)
+
+
+def brightness(img, factor, **__):
+    return ImageEnhance.Brightness(img).enhance(factor)
+
+
+def sharpness(img, factor, **__):
+    return ImageEnhance.Sharpness(img).enhance(factor)
+
+
+def _randomly_negate(v):
+    """With 50% prob, negate the value"""
+    return -v if random.random() > 0.5 else v
+
+
+def _rotate_level_to_arg(level):
+    # range [-30, 30]
+    level = (level / _MAX_LEVEL) * 30.
+    level = _randomly_negate(level)
+    return (level,)
+
+
+def _enhance_level_to_arg(level):
+    # range [0.1, 1.9]
+    return ((level / _MAX_LEVEL) * 1.8 + 0.1,)
+
+
+def _shear_level_to_arg(level):
+    # range [-0.3, 0.3]
+    level = (level / _MAX_LEVEL) * 0.3
+    level = _randomly_negate(level)
+    return (level,)
+
+
+def _translate_abs_level_to_arg(level, translate_const):
+    level = (level / _MAX_LEVEL) * float(translate_const)
+    level = _randomly_negate(level)
+    return (level,)
+
+
+def _translate_rel_level_to_arg(level):
+    # range [-0.45, 0.45]
+    level = (level / _MAX_LEVEL) * 0.45
+    level = _randomly_negate(level)
+    return (level,)
+
+
+def level_to_arg(hparams):
+    return {
+        'AutoContrast': lambda level: (),
+        'Equalize': lambda level: (),
+        'Invert': lambda level: (),
+        'Rotate': _rotate_level_to_arg,
+        # FIXME these are both different from original impl as I believe there is a bug,
+        # not sure what is the correct alternative, hence 2 options that look better
+        'Posterize': lambda level: (int((level / _MAX_LEVEL) * 4) + 4,),  # range [4, 8]
+        'Posterize2': lambda level: (4 - int((level / _MAX_LEVEL) * 4),),  # range [4, 0]
+        'Solarize': lambda level: (int((level / _MAX_LEVEL) * 256),),  # range [0, 256]
+        'SolarizeAdd': lambda level: (int((level / _MAX_LEVEL) * 110),),  # range [0, 110]
+        'Color': _enhance_level_to_arg,
+        'Contrast': _enhance_level_to_arg,
+        'Brightness': _enhance_level_to_arg,
+        'Sharpness': _enhance_level_to_arg,
+        'ShearX': _shear_level_to_arg,
+        'ShearY': _shear_level_to_arg,
+        'TranslateX': lambda level: _translate_abs_level_to_arg(level, hparams['translate_const']),
+        'TranslateY': lambda level: _translate_abs_level_to_arg(level, hparams['translate_const']),
+        'TranslateXRel': lambda level: _translate_rel_level_to_arg(level),
+        'TranslateYRel': lambda level: _translate_rel_level_to_arg(level),
+    }
+
+
+NAME_TO_OP = {
+    'AutoContrast': auto_contrast,
+    'Equalize': equalize,
+    'Invert': invert,
+    'Rotate': rotate,
+    'Posterize': posterize,
+    'Posterize2': posterize,
+    'Solarize': solarize,
+    'SolarizeAdd': solarize_add,
+    'Color': color,
+    'Contrast': contrast,
+    'Brightness': brightness,
+    'Sharpness': sharpness,
+    'ShearX': shear_x,
+    'ShearY': shear_y,
+    'TranslateX': translate_x_abs,
+    'TranslateY': translate_y_abs,
+    'TranslateXRel': translate_x_rel,
+    'TranslateYRel': translate_y_rel,
+}
+
+
+class AutoAugmentOp:
+
+    def __init__(self, name, prob, magnitude, hparams={}):
+        self.aug_fn = NAME_TO_OP[name]
+        self.level_fn = level_to_arg(hparams)[name]
+        self.prob = prob
+        self.magnitude = magnitude
+        # If std deviation of magnitude is > 0, we introduce some randomness
+        # in the usually fixed policy and sample magnitude from normal dist
+        # with mean magnitude and std-dev of magnitude_std.
+        # NOTE This is being tested as it's not in paper or reference impl.
+        self.magnitude_std = 0.5  # FIXME add arg/hparam
+        self.kwargs = {
+            'fillcolor': hparams['img_mean'] if 'img_mean' in hparams else _FILL,
+            'resample': hparams['interpolation'] if 'interpolation' in hparams else _RANDOM_INTERPOLATION
+        }
+
+    def __call__(self, img):
+        if self.prob < random.random():
+            return img
+        magnitude = self.magnitude
+        if self.magnitude_std and self.magnitude_std > 0:
+            magnitude = random.gauss(magnitude, self.magnitude_std)
+        magnitude = min(_MAX_LEVEL, max(0, magnitude))
+        level_args = self.level_fn(magnitude)
+        return self.aug_fn(img, *level_args, **self.kwargs)
+
+
+def auto_augment_policy_v0(hparams=_HPARAMS_DEFAULT):
+    # ImageNet policy from TPU EfficientNet impl, cannot find
+    # a paper reference.
+    policy = [
+        [('Equalize', 0.8, 1), ('ShearY', 0.8, 4)],
+        [('Color', 0.4, 9), ('Equalize', 0.6, 3)],
+        [('Color', 0.4, 1), ('Rotate', 0.6, 8)],
+        [('Solarize', 0.8, 3), ('Equalize', 0.4, 7)],
+        [('Solarize', 0.4, 2), ('Solarize', 0.6, 2)],
+        [('Color', 0.2, 0), ('Equalize', 0.8, 8)],
+        [('Equalize', 0.4, 8), ('SolarizeAdd', 0.8, 3)],
+        [('ShearX', 0.2, 9), ('Rotate', 0.6, 8)],
+        [('Color', 0.6, 1), ('Equalize', 1.0, 2)],
+        [('Invert', 0.4, 9), ('Rotate', 0.6, 0)],
+        [('Equalize', 1.0, 9), ('ShearY', 0.6, 3)],
+        [('Color', 0.4, 7), ('Equalize', 0.6, 0)],
+        [('Posterize', 0.4, 6), ('AutoContrast', 0.4, 7)],
+        [('Solarize', 0.6, 8), ('Color', 0.6, 9)],
+        [('Solarize', 0.2, 4), ('Rotate', 0.8, 9)],
+        [('Rotate', 1.0, 7), ('TranslateYRel', 0.8, 9)],
+        [('ShearX', 0.0, 0), ('Solarize', 0.8, 4)],
+        [('ShearY', 0.8, 0), ('Color', 0.6, 4)],
+        [('Color', 1.0, 0), ('Rotate', 0.6, 2)],
+        [('Equalize', 0.8, 4), ('Equalize', 0.0, 8)],
+        [('Equalize', 1.0, 4), ('AutoContrast', 0.6, 2)],
+        [('ShearY', 0.4, 7), ('SolarizeAdd', 0.6, 7)],
+        [('Posterize', 0.8, 2), ('Solarize', 0.6, 10)],
+        [('Solarize', 0.6, 8), ('Equalize', 0.6, 1)],
+        [('Color', 0.8, 6), ('Rotate', 0.4, 5)],
+    ]
+    pc = [[AutoAugmentOp(*a, hparams) for a in sp] for sp in policy]
+    return pc
+
+
+def auto_augment_policy_original(hparams=_HPARAMS_DEFAULT):
+    # ImageNet policy from https://arxiv.org/abs/1805.09501
+    policy = [
+        [('Posterize', 0.4, 8), ('Rotate', 0.6, 9)],
+        [('Solarize', 0.6, 5), ('AutoContrast', 0.6, 5)],
+        [('Equalize', 0.8, 8), ('Equalize', 0.6, 3)],
+        [('Posterize', 0.6, 7), ('Posterize', 0.6, 6)],
+        [('Equalize', 0.4, 7), ('Solarize', 0.2, 4)],
+        [('Equalize', 0.4, 4), ('Rotate', 0.8, 8)],
+        [('Solarize', 0.6, 3), ('Equalize', 0.6, 7)],
+        [('Posterize', 0.8, 5), ('Equalize', 1.0, 2)],
+        [('Rotate', 0.2, 3), ('Solarize', 0.6, 8)],
+        [('Equalize', 0.6, 8), ('Posterize', 0.4, 6)],
+        [('Rotate', 0.8, 8), ('Color', 0.4, 0)],
+        [('Rotate', 0.4, 9), ('Equalize', 0.6, 2)],
+        [('Equalize', 0.0, 7), ('Equalize', 0.8, 8)],
+        [('Invert', 0.6, 4), ('Equalize', 1.0, 8)],
+        [('Color', 0.6, 4), ('Contrast', 1.0, 8)],
+        [('Rotate', 0.8, 8), ('Color', 1.0, 2)],
+        [('Color', 0.8, 8), ('Solarize', 0.8, 7)],
+        [('Sharpness', 0.4, 7), ('Invert', 0.6, 8)],
+        [('ShearX', 0.6, 5), ('Equalize', 1.0, 9)],
+        [('Color', 0.4, 0), ('Equalize', 0.6, 3)],
+        [('Equalize', 0.4, 7), ('Solarize', 0.2, 4)],
+        [('Solarize', 0.6, 5), ('AutoContrast', 0.6, 5)],
+        [('Invert', 0.6, 4), ('Equalize', 1.0, 8)],
+        [('Color', 0.6, 4), ('Contrast', 1.0, 8)],
+        [('Equalize', 0.8, 8), ('Equalize', 0.6, 3)],
+    ]
+    pc = [[AutoAugmentOp(*a, hparams) for a in sp] for sp in policy]
+    return pc
+
+
+def auto_augment_policy(name='v0', hparams=_HPARAMS_DEFAULT):
+    if name == 'original':
+        return auto_augment_policy_original(hparams)
+    elif name == 'v0':
+        return auto_augment_policy_v0(hparams)
+    else:
+        assert False, 'Unknown AA policy (%s)' % name
+
+
+class AutoAugment:
+
+    def __init__(self, policy):
+        self.policy = policy
+
+    def __call__(self, img):
+        sub_policy = random.choice(self.policy)
+        for op in sub_policy:
+            img = op(img)
+        return img

timm/data/loader.py

@@ -92,6 +92,7 @@ def create_transform(
         is_training=False,
         use_prefetcher=False,
         color_jitter=0.4,
+        auto_augment=None,
         interpolation='bilinear',
         mean=IMAGENET_DEFAULT_MEAN,
         std=IMAGENET_DEFAULT_STD,
@@ -112,6 +113,7 @@ def create_transform(
             transform = transforms_imagenet_train(
                 img_size,
                 color_jitter=color_jitter,
+                auto_augment=auto_augment,
                 interpolation=interpolation,
                 use_prefetcher=use_prefetcher,
                 mean=mean,
@@ -138,6 +140,7 @@ def create_loader(
         rand_erase_mode='const',
         rand_erase_count=1,
         color_jitter=0.4,
+        auto_augment=None,
         interpolation='bilinear',
         mean=IMAGENET_DEFAULT_MEAN,
         std=IMAGENET_DEFAULT_STD,
@@ -153,6 +156,7 @@ def create_loader(
         is_training=is_training,
         use_prefetcher=use_prefetcher,
         color_jitter=color_jitter,
+        auto_augment=auto_augment,
         interpolation=interpolation,
         mean=mean,
         std=std,