You can not select more than 25 topics
Topics must start with a letter or number, can include dashes ('-') and can be up to 35 characters long.
68 lines
2.2 KiB
68 lines
2.2 KiB
3 years ago
|
# copyright (c) 2021 PaddlePaddle Authors. All Rights Reserve.
|
||
|
#
|
||
|
# 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.
|
||
|
|
||
|
import warnings
|
||
|
|
||
|
import paddle
|
||
|
import paddle.nn as nn
|
||
|
import paddle.nn.functional as F
|
||
|
|
||
|
from ppcls.utils import logger
|
||
|
|
||
|
|
||
|
class CELoss(nn.Layer):
|
||
|
"""
|
||
|
Cross entropy loss
|
||
|
"""
|
||
|
|
||
|
def __init__(self, epsilon=None):
|
||
|
super().__init__()
|
||
|
if epsilon is not None and (epsilon <= 0 or epsilon >= 1):
|
||
|
epsilon = None
|
||
|
self.epsilon = epsilon
|
||
|
|
||
|
def _labelsmoothing(self, target, class_num):
|
||
|
if len(target.shape) == 1 or target.shape[-1] != class_num:
|
||
|
one_hot_target = F.one_hot(target, class_num)
|
||
|
else:
|
||
|
one_hot_target = target
|
||
|
soft_target = F.label_smooth(one_hot_target, epsilon=self.epsilon)
|
||
|
soft_target = paddle.reshape(soft_target, shape=[-1, class_num])
|
||
|
return soft_target
|
||
|
|
||
|
def forward(self, x, label):
|
||
|
if isinstance(x, dict):
|
||
|
x = x["logits"]
|
||
|
if self.epsilon is not None:
|
||
|
class_num = x.shape[-1]
|
||
|
label = self._labelsmoothing(label, class_num)
|
||
|
x = -F.log_softmax(x, axis=-1)
|
||
|
loss = paddle.sum(x * label, axis=-1)
|
||
|
else:
|
||
|
if label.shape[-1] == x.shape[-1]:
|
||
|
label = F.softmax(label, axis=-1)
|
||
|
soft_label = True
|
||
|
else:
|
||
|
soft_label = False
|
||
|
loss = F.cross_entropy(x, label=label, soft_label=soft_label)
|
||
|
loss = loss.mean()
|
||
|
return {"CELoss": loss}
|
||
|
|
||
|
|
||
|
class MixCELoss(object):
|
||
|
def __init__(self, *args, **kwargs):
|
||
|
msg = "\"MixCELos\" is deprecated, please use \"CELoss\" instead."
|
||
|
logger.error(DeprecationWarning(msg))
|
||
|
raise DeprecationWarning(msg)
|