PaddleClas/ppcls/data/preprocess/batch_ops/batch_operators.py

502 lines
19 KiB
Python

# Copyright (c) 2021 PaddlePaddle Authors. All Rights Reserved.
#
# Licensed under the Apache License, Version 2.0 (the "License");
# you may not use this file except in compliance with the License.
# You may obtain a copy of the License at
#
# http://www.apache.org/licenses/LICENSE-2.0
#
# Unless required by applicable law or agreed to in writing, software
# distributed under the License is distributed on an "AS IS" BASIS,
# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
# See the License for the specific language governing permissions and
# limitations under the License.
from __future__ import absolute_import
from __future__ import division
from __future__ import print_function
from __future__ import unicode_literals
import random
import numpy as np
from ppcls.utils import logger
from ppcls.data.preprocess.ops.fmix import sample_mask
import paddle
import paddle.nn.functional as F
class BatchOperator(object):
""" BatchOperator """
def __init__(self, *args, **kwargs):
pass
def _unpack(self, batch):
""" _unpack """
assert isinstance(batch, list), \
'batch should be a list filled with tuples (img, label)'
bs = len(batch)
assert bs > 0, 'size of the batch data should > 0'
#imgs, labels = list(zip(*batch))
imgs = []
labels = []
for item in batch:
imgs.append(item[0])
labels.append(item[1])
return np.array(imgs), np.array(labels), bs
def _one_hot(self, targets):
return np.eye(self.class_num, dtype="float32")[targets]
def _mix_target(self, targets0, targets1, lam):
one_hots0 = self._one_hot(targets0)
one_hots1 = self._one_hot(targets1)
return one_hots0 * lam + one_hots1 * (1 - lam)
def __call__(self, batch):
return batch
class MixupOperator(BatchOperator):
""" Mixup operator
reference: https://arxiv.org/abs/1710.09412
"""
def __init__(self, class_num, alpha: float=1.):
"""Build Mixup operator
Args:
alpha (float, optional): The parameter alpha of mixup. Defaults to 1..
Raises:
Exception: The value of parameter is illegal.
"""
if alpha <= 0:
raise Exception(
f"Parameter \"alpha\" of Mixup should be greater than 0. \"alpha\": {alpha}."
)
if not class_num:
msg = "Please set \"Arch.class_num\" in config if use \"MixupOperator\"."
logger.error(Exception(msg))
raise Exception(msg)
self._alpha = alpha
self.class_num = class_num
def __call__(self, batch):
imgs, labels, bs = self._unpack(batch)
idx = np.random.permutation(bs)
lam = np.random.beta(self._alpha, self._alpha)
imgs = lam * imgs + (1 - lam) * imgs[idx]
targets = self._mix_target(labels, labels[idx], lam)
return list(zip(imgs, targets))
class CutmixOperator(BatchOperator):
""" Cutmix operator
reference: https://arxiv.org/abs/1905.04899
"""
def __init__(self, class_num, alpha=0.2):
"""Build Cutmix operator
Args:
alpha (float, optional): The parameter alpha of cutmix. Defaults to 0.2.
Raises:
Exception: The value of parameter is illegal.
"""
if alpha <= 0:
raise Exception(
f"Parameter \"alpha\" of Cutmix should be greater than 0. \"alpha\": {alpha}."
)
if not class_num:
msg = "Please set \"Arch.class_num\" in config if use \"CutmixOperator\"."
logger.error(Exception(msg))
raise Exception(msg)
self._alpha = alpha
self.class_num = class_num
def _rand_bbox(self, size, lam):
""" _rand_bbox """
w = size[2]
h = size[3]
cut_rat = np.sqrt(1. - lam)
cut_w = int(w * cut_rat)
cut_h = int(h * cut_rat)
# uniform
cx = np.random.randint(w)
cy = np.random.randint(h)
bbx1 = np.clip(cx - cut_w // 2, 0, w)
bby1 = np.clip(cy - cut_h // 2, 0, h)
bbx2 = np.clip(cx + cut_w // 2, 0, w)
bby2 = np.clip(cy + cut_h // 2, 0, h)
return bbx1, bby1, bbx2, bby2
def __call__(self, batch):
imgs, labels, bs = self._unpack(batch)
idx = np.random.permutation(bs)
lam = np.random.beta(self._alpha, self._alpha)
bbx1, bby1, bbx2, bby2 = self._rand_bbox(imgs.shape, lam)
imgs[:, :, bbx1:bbx2, bby1:bby2] = imgs[idx, :, bbx1:bbx2, bby1:bby2]
lam = 1 - (float(bbx2 - bbx1) * (bby2 - bby1) /
(imgs.shape[-2] * imgs.shape[-1]))
targets = self._mix_target(labels, labels[idx], lam)
return list(zip(imgs, targets))
class FmixOperator(BatchOperator):
""" Fmix operator
reference: https://arxiv.org/abs/2002.12047
"""
def __init__(self,
class_num,
alpha=1,
decay_power=3,
max_soft=0.,
reformulate=False):
if not class_num:
msg = "Please set \"Arch.class_num\" in config if use \"FmixOperator\"."
logger.error(Exception(msg))
raise Exception(msg)
self._alpha = alpha
self._decay_power = decay_power
self._max_soft = max_soft
self._reformulate = reformulate
self.class_num = class_num
def __call__(self, batch):
imgs, labels, bs = self._unpack(batch)
idx = np.random.permutation(bs)
size = (imgs.shape[2], imgs.shape[3])
lam, mask = sample_mask(self._alpha, self._decay_power, \
size, self._max_soft, self._reformulate)
imgs = mask * imgs + (1 - mask) * imgs[idx]
targets = self._mix_target(labels, labels[idx], lam)
return list(zip(imgs, targets))
class OpSampler(object):
""" Sample a operator from """
def __init__(self, class_num, **op_dict):
"""Build OpSampler
Raises:
Exception: The parameter \"prob\" of operator(s) are be set error.
"""
if not class_num:
msg = "Please set \"Arch.class_num\" in config if use \"OpSampler\"."
logger.error(Exception(msg))
raise Exception(msg)
if len(op_dict) < 1:
msg = f"ConfigWarning: No operator in \"OpSampler\". \"OpSampler\" has been skipped."
logger.warning(msg)
self.ops = {}
total_prob = 0
for op_name in op_dict:
param = op_dict[op_name]
if "prob" not in param:
msg = f"ConfigWarning: Parameter \"prob\" should be set when use operator in \"OpSampler\". The operator \"{op_name}\"'s prob has been set \"0\"."
logger.warning(msg)
prob = param.pop("prob", 0)
total_prob += prob
param.update({"class_num": class_num})
op = eval(op_name)(**param)
self.ops.update({op: prob})
if total_prob > 1:
msg = f"ConfigError: The total prob of operators in \"OpSampler\" should be less 1."
logger.error(Exception(msg))
raise Exception(msg)
# add "None Op" when total_prob < 1, "None Op" do nothing
self.ops[None] = 1 - total_prob
def __call__(self, batch):
op = random.choices(
list(self.ops.keys()), weights=list(self.ops.values()), k=1)[0]
# return batch directly when None Op
return op(batch) if op else batch
class MixupCutmixHybrid(object):
""" Mixup/Cutmix that applies different params to each element or whole batch
Args:
mixup_alpha (float): mixup alpha value, mixup is active if > 0.
cutmix_alpha (float): cutmix alpha value, cutmix is active if > 0.
cutmix_minmax (List[float]): cutmix min/max image ratio, cutmix is active and uses this vs alpha if not None.
prob (float): probability of applying mixup or cutmix per batch or element
switch_prob (float): probability of switching to cutmix instead of mixup when both are active
mode (str): how to apply mixup/cutmix params (per 'batch', 'pair' (pair of elements), 'elem' (element)
correct_lam (bool): apply lambda correction when cutmix bbox clipped by image borders
label_smoothing (float): apply label smoothing to the mixed target tensor
num_classes (int): number of classes for target
"""
def __init__(self,
mixup_alpha=1.,
cutmix_alpha=0.,
cutmix_minmax=None,
prob=1.0,
switch_prob=0.5,
mode='batch',
correct_lam=True,
label_smoothing=0.1,
num_classes=4):
self.mixup_alpha = mixup_alpha
self.cutmix_alpha = cutmix_alpha
self.cutmix_minmax = cutmix_minmax
if self.cutmix_minmax is not None:
assert len(self.cutmix_minmax) == 2
# force cutmix alpha == 1.0 when minmax active to keep logic simple & safe
self.cutmix_alpha = 1.0
self.mix_prob = prob
self.switch_prob = switch_prob
self.label_smoothing = label_smoothing
self.num_classes = num_classes
self.mode = mode
self.correct_lam = correct_lam # correct lambda based on clipped area for cutmix
self.mixup_enabled = True # set to false to disable mixing (intended tp be set by train loop)
def _one_hot(self, x, num_classes, on_value=1., off_value=0.):
x = paddle.cast(x, dtype='int64')
on_value = paddle.full([x.shape[0], num_classes], on_value)
off_value = paddle.full([x.shape[0], num_classes], off_value)
return paddle.where(
F.one_hot(x, num_classes) == 1, on_value, off_value)
def _mixup_target(self, target, num_classes, lam=1., smoothing=0.0):
off_value = smoothing / num_classes
on_value = 1. - smoothing + off_value
y1 = self._one_hot(
target,
num_classes,
on_value=on_value,
off_value=off_value, )
y2 = self._one_hot(
target.flip(0),
num_classes,
on_value=on_value,
off_value=off_value)
return y1 * lam + y2 * (1. - lam)
def _rand_bbox(self, img_shape, lam, margin=0., count=None):
""" Standard CutMix bounding-box
Generates a random square bbox based on lambda value. This impl includes
support for enforcing a border margin as percent of bbox dimensions.
Args:
img_shape (tuple): Image shape as tuple
lam (float): Cutmix lambda value
margin (float): Percentage of bbox dimension to enforce as margin (reduce amount of box outside image)
count (int): Number of bbox to generate
"""
ratio = np.sqrt(1 - lam)
img_h, img_w = img_shape[-2:]
cut_h, cut_w = int(img_h * ratio), int(img_w * ratio)
margin_y, margin_x = int(margin * cut_h), int(margin * cut_w)
cy = np.random.randint(0 + margin_y, img_h - margin_y, size=count)
cx = np.random.randint(0 + margin_x, img_w - margin_x, size=count)
yl = np.clip(cy - cut_h // 2, 0, img_h)
yh = np.clip(cy + cut_h // 2, 0, img_h)
xl = np.clip(cx - cut_w // 2, 0, img_w)
xh = np.clip(cx + cut_w // 2, 0, img_w)
return yl, yh, xl, xh
def _rand_bbox_minmax(self, img_shape, minmax, count=None):
""" Min-Max CutMix bounding-box
Inspired by Darknet cutmix impl, generates a random rectangular bbox
based on min/max percent values applied to each dimension of the input image.
Typical defaults for minmax are usually in the .2-.3 for min and .8-.9 range for max.
Args:
img_shape (tuple): Image shape as tuple
minmax (tuple or list): Min and max bbox ratios (as percent of image size)
count (int): Number of bbox to generate
"""
assert len(minmax) == 2
img_h, img_w = img_shape[-2:]
cut_h = np.random.randint(
int(img_h * minmax[0]), int(img_h * minmax[1]), size=count)
cut_w = np.random.randint(
int(img_w * minmax[0]), int(img_w * minmax[1]), size=count)
yl = np.random.randint(0, img_h - cut_h, size=count)
xl = np.random.randint(0, img_w - cut_w, size=count)
yu = yl + cut_h
xu = xl + cut_w
return yl, yu, xl, xu
def _cutmix_bbox_and_lam(self,
img_shape,
lam,
ratio_minmax=None,
correct_lam=True,
count=None):
""" Generate bbox and apply lambda correction.
"""
if ratio_minmax is not None:
yl, yu, xl, xu = self._rand_bbox_minmax(
img_shape, ratio_minmax, count=count)
else:
yl, yu, xl, xu = self._rand_bbox(img_shape, lam, count=count)
if correct_lam or ratio_minmax is not None:
bbox_area = (yu - yl) * (xu - xl)
lam = 1. - bbox_area / float(img_shape[-2] * img_shape[-1])
return (yl, yu, xl, xu), lam
def _params_per_elem(self, batch_size):
lam = np.ones(batch_size, dtype=np.float32)
use_cutmix = np.zeros(batch_size, dtype=np.bool)
if self.mixup_enabled:
if self.mixup_alpha > 0. and self.cutmix_alpha > 0.:
use_cutmix = np.random.rand(batch_size) < self.switch_prob
lam_mix = np.where(
use_cutmix,
np.random.beta(
self.cutmix_alpha, self.cutmix_alpha, size=batch_size),
np.random.beta(
self.mixup_alpha, self.mixup_alpha, size=batch_size))
elif self.mixup_alpha > 0.:
lam_mix = np.random.beta(
self.mixup_alpha, self.mixup_alpha, size=batch_size)
elif self.cutmix_alpha > 0.:
use_cutmix = np.ones(batch_size, dtype=np.bool)
lam_mix = np.random.beta(
self.cutmix_alpha, self.cutmix_alpha, size=batch_size)
else:
assert False, "One of mixup_alpha > 0., cutmix_alpha > 0., cutmix_minmax not None should be true."
lam = np.where(
np.random.rand(batch_size) < self.mix_prob,
lam_mix.astype(np.float32), lam)
return lam, use_cutmix
def _params_per_batch(self):
lam = 1.
use_cutmix = False
if self.mixup_enabled and np.random.rand() < self.mix_prob:
if self.mixup_alpha > 0. and self.cutmix_alpha > 0.:
use_cutmix = np.random.rand() < self.switch_prob
lam_mix = np.random.beta(self.cutmix_alpha, self.cutmix_alpha) if use_cutmix else \
np.random.beta(self.mixup_alpha, self.mixup_alpha)
elif self.mixup_alpha > 0.:
lam_mix = np.random.beta(self.mixup_alpha, self.mixup_alpha)
elif self.cutmix_alpha > 0.:
use_cutmix = True
lam_mix = np.random.beta(self.cutmix_alpha, self.cutmix_alpha)
else:
assert False, "One of mixup_alpha > 0., cutmix_alpha > 0., cutmix_minmax not None should be true."
lam = float(lam_mix)
return lam, use_cutmix
def _mix_elem(self, x):
batch_size = len(x)
lam_batch, use_cutmix = self._params_per_elem(batch_size)
x_orig = x.clone(
) # need to keep an unmodified original for mixing source
for i in range(batch_size):
j = batch_size - i - 1
lam = lam_batch[i]
if lam != 1.:
if use_cutmix[i]:
(yl, yh, xl, xh), lam = self._cutmix_bbox_and_lam(
x[i].shape,
lam,
ratio_minmax=self.cutmix_minmax,
correct_lam=self.correct_lam)
if yl < yh and xl < xh:
x[i][:, yl:yh, xl:xh] = x_orig[j][:, yl:yh, xl:xh]
lam_batch[i] = lam
else:
x[i] = x[i] * lam + x_orig[j] * (1 - lam)
return paddle.to_tensor(lam_batch, dtype=x.dtype).unsqueeze(1)
def _mix_pair(self, x):
batch_size = len(x)
lam_batch, use_cutmix = self._params_per_elem(batch_size // 2)
x_orig = x.clone(
) # need to keep an unmodified original for mixing source
for i in range(batch_size // 2):
j = batch_size - i - 1
lam = lam_batch[i]
if lam != 1.:
if use_cutmix[i]:
(yl, yh, xl, xh), lam = self._cutmix_bbox_and_lam(
x[i].shape,
lam,
ratio_minmax=self.cutmix_minmax,
correct_lam=self.correct_lam)
if yl < yh and xl < xh:
x[i][:, yl:yh, xl:xh] = x_orig[j][:, yl:yh, xl:xh]
x[j][:, yl:yh, xl:xh] = x_orig[i][:, yl:yh, xl:xh]
lam_batch[i] = lam
else:
x[i] = x[i] * lam + x_orig[j] * (1 - lam)
x[j] = x[j] * lam + x_orig[i] * (1 - lam)
lam_batch = np.concatenate((lam_batch, lam_batch[::-1]))
return paddle.to_tensor(lam_batch, dtype=x.dtype).unsqueeze(1)
def _mix_batch(self, x):
lam, use_cutmix = self._params_per_batch()
if lam == 1.:
return 1.
if use_cutmix:
(yl, yh, xl, xh), lam = self._cutmix_bbox_and_lam(
x.shape,
lam,
ratio_minmax=self.cutmix_minmax,
correct_lam=self.correct_lam)
if yl < yh and xl < xh:
x[:, :, yl:yh, xl:xh] = x.flip(0)[:, :, yl:yh, xl:xh]
else:
x_flipped = x.flip(0) * (1. - lam)
x[:] = x * lam + x_flipped
return lam
def _unpack(self, batch):
""" _unpack """
assert isinstance(batch, list), \
'batch should be a list filled with tuples (img, label)'
bs = len(batch)
assert bs > 0, 'size of the batch data should > 0'
#imgs, labels = list(zip(*batch))
imgs = []
labels = []
for item in batch:
imgs.append(item[0])
labels.append(item[1])
return np.array(imgs), np.array(labels), bs
def __call__(self, batch):
x, target, bs = self._unpack(batch)
x = paddle.to_tensor(x)
target = paddle.to_tensor(target)
assert len(x) % 2 == 0, 'Batch size should be even when using this'
if self.mode == 'elem':
lam = self._mix_elem(x)
elif self.mode == 'pair':
lam = self._mix_pair(x)
else:
lam = self._mix_batch(x)
target = self._mixup_target(target, self.num_classes, lam,
self.label_smoothing)
return list(zip(x.numpy(), target.numpy()))