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

232 lines
7.4 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
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