""" Transforms Factory
Factory methods for building image transforms for use with TIMM (PyTorch Image Models)
Hacked together by / Copyright 2020 Ross Wightman
"""
import math
import torch
from torchvision import transforms
from timm.data.constants import IMAGENET_DEFAULT_MEAN, IMAGENET_DEFAULT_STD, DEFAULT_CROP_PCT
from timm.data.auto_augment import rand_augment_transform, augment_and_mix_transform, auto_augment_transform
from timm.data.transforms import _pil_interp, RandomResizedCropAndInterpolation, ToNumpy, ToTensor
from timm.data.random_erasing import RandomErasing
def transforms_noaug_train(
img_size=224,
interpolation='bilinear',
use_prefetcher=False,
mean=IMAGENET_DEFAULT_MEAN,
std=IMAGENET_DEFAULT_STD,
):
if interpolation == 'random':
# random interpolation not supported with no-aug
interpolation = 'bilinear'
tfl = [
transforms.Resize(img_size, _pil_interp(interpolation)),
transforms.CenterCrop(img_size)
]
if use_prefetcher:
# prefetcher and collate will handle tensor conversion and norm
tfl += [ToNumpy()]
else:
tfl += [
transforms.ToTensor(),
transforms.Normalize(
mean=torch.tensor(mean),
std=torch.tensor(std))
]
return transforms.Compose(tfl)
def transforms_imagenet_train(
img_size=224,
scale=None,
ratio=None,
hflip=0.5,
vflip=0.,
color_jitter=0.4,
auto_augment=None,
interpolation='random',
use_prefetcher=False,
mean=IMAGENET_DEFAULT_MEAN,
std=IMAGENET_DEFAULT_STD,
re_prob=0.,
re_mode='const',
re_count=1,
re_num_splits=0,
separate=False,
):
"""
If separate==True, the transforms are returned as a tuple of 3 separate transforms
for use in a mixing dataset that passes
* all data through the first (primary) transform, called the 'clean' data
* a portion of the data through the secondary transform
* normalizes and converts the branches above with the third, final transform
"""
scale = tuple(scale or (0.08, 1.0)) # default imagenet scale range
ratio = tuple(ratio or (3./4., 4./3.)) # default imagenet ratio range
primary_tfl = [
RandomResizedCropAndInterpolation(img_size, scale=scale, ratio=ratio, interpolation=interpolation)]
if hflip > 0.:
primary_tfl += [transforms.RandomHorizontalFlip(p=hflip)]
if vflip > 0.:
primary_tfl += [transforms.RandomVerticalFlip(p=vflip)]
secondary_tfl = []
if auto_augment:
assert isinstance(auto_augment, str)
if isinstance(img_size, tuple):
img_size_min = min(img_size)
else:
img_size_min = img_size
aa_params = dict(
translate_const=int(img_size_min * 0.45),
img_mean=tuple([min(255, round(255 * x)) for x in mean]),
)
if interpolation and interpolation != 'random':
aa_params['interpolation'] = _pil_interp(interpolation)
if auto_augment.startswith('rand'):
secondary_tfl += [rand_augment_transform(auto_augment, aa_params)]
elif auto_augment.startswith('augmix'):
aa_params['translate_pct'] = 0.3
secondary_tfl += [augment_and_mix_transform(auto_augment, aa_params)]
else:
secondary_tfl += [auto_augment_transform(auto_augment, aa_params)]
elif color_jitter is not None:
# color jitter is enabled when not using AA
if isinstance(color_jitter, (list, tuple)):
# color jitter should be a 3-tuple/list if spec brightness/contrast/saturation
# or 4 if also augmenting hue
assert len(color_jitter) in (3, 4)
else:
# if it's a scalar, duplicate for brightness, contrast, and saturation, no hue
color_jitter = (float(color_jitter),) * 3
secondary_tfl += [transforms.ColorJitter(*color_jitter)]
final_tfl = []
if use_prefetcher:
# prefetcher and collate will handle tensor conversion and norm
final_tfl += [ToNumpy()]
else:
final_tfl += [
transforms.ToTensor(),
transforms.Normalize(
mean=torch.tensor(mean),
std=torch.tensor(std))
]
if re_prob > 0.:
final_tfl.append(
RandomErasing(re_prob, mode=re_mode, max_count=re_count, num_splits=re_num_splits, device='cpu'))
if separate:
return transforms.Compose(primary_tfl), transforms.Compose(secondary_tfl), transforms.Compose(final_tfl)
else:
return transforms.Compose(primary_tfl + secondary_tfl + final_tfl)
def transforms_imagenet_eval(
img_size=224,
crop_pct=None,
interpolation='bilinear',
use_prefetcher=False,
mean=IMAGENET_DEFAULT_MEAN,
std=IMAGENET_DEFAULT_STD):
crop_pct = crop_pct or DEFAULT_CROP_PCT
if isinstance(img_size, tuple):
assert len(img_size) == 2
if img_size[-1] == img_size[-2]:
# fall-back to older behaviour so Resize scales to shortest edge if target is square
scale_size = int(math.floor(img_size[0] / crop_pct))
else:
scale_size = tuple([int(x / crop_pct) for x in img_size])
else:
scale_size = int(math.floor(img_size / crop_pct))
tfl = [
transforms.Resize(scale_size, _pil_interp(interpolation)),
transforms.CenterCrop(img_size),
]
if use_prefetcher:
# prefetcher and collate will handle tensor conversion and norm
tfl += [ToNumpy()]
else:
tfl += [
transforms.ToTensor(),
transforms.Normalize(
mean=torch.tensor(mean),
std=torch.tensor(std))
]
return transforms.Compose(tfl)
def create_transform(
input_size,
is_training=False,
use_prefetcher=False,
no_aug=False,
scale=None,
ratio=None,
hflip=0.5,
vflip=0.,
color_jitter=0.4,
auto_augment=None,
interpolation='bilinear',
mean=IMAGENET_DEFAULT_MEAN,
std=IMAGENET_DEFAULT_STD,
re_prob=0.,
re_mode='const',
re_count=1,
re_num_splits=0,
crop_pct=None,
tf_preprocessing=False,
separate=False):
if isinstance(input_size, tuple):
img_size = input_size[-2:]
else:
img_size = input_size
if tf_preprocessing and use_prefetcher:
assert not separate, "Separate transforms not supported for TF preprocessing"
from timm.data.tf_preprocessing import TfPreprocessTransform
transform = TfPreprocessTransform(
is_training=is_training, size=img_size, interpolation=interpolation)
else:
if is_training and no_aug:
assert not separate, "Cannot perform split augmentation with no_aug"
transform = transforms_noaug_train(
img_size,
interpolation=interpolation,
use_prefetcher=use_prefetcher,
mean=mean,
std=std)
elif is_training:
transform = transforms_imagenet_train(
img_size,
scale=scale,
ratio=ratio,
hflip=hflip,
vflip=vflip,
color_jitter=color_jitter,
auto_augment=auto_augment,
interpolation=interpolation,
use_prefetcher=use_prefetcher,
mean=mean,
std=std,
re_prob=re_prob,
re_mode=re_mode,
re_count=re_count,
re_num_splits=re_num_splits,
separate=separate)
else:
assert not separate, "Separate transforms not supported for validation preprocessing"
transform = transforms_imagenet_eval(
img_size,
interpolation=interpolation,
use_prefetcher=use_prefetcher,
mean=mean,
std=std,
crop_pct=crop_pct)
return transform