PaddleOCR/ppocr/modeling/heads/rec_ctc_head.py

55 lines
1.9 KiB
Python
Executable File

# copyright (c) 2019 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.
from __future__ import absolute_import
from __future__ import division
from __future__ import print_function
import math
import paddle
from paddle import ParamAttr, nn
from paddle.nn import functional as F
def get_para_bias_attr(l2_decay, k, name):
regularizer = paddle.regularizer.L2Decay(l2_decay)
stdv = 1.0 / math.sqrt(k * 1.0)
initializer = nn.initializer.Uniform(-stdv, stdv)
weight_attr = ParamAttr(
regularizer=regularizer, initializer=initializer, name=name + "_w_attr")
bias_attr = ParamAttr(
regularizer=regularizer, initializer=initializer, name=name + "_b_attr")
return [weight_attr, bias_attr]
class CTCHead(nn.Layer):
def __init__(self, in_channels, out_channels, fc_decay=0.0004, **kwargs):
super(CTCHead, self).__init__()
weight_attr, bias_attr = get_para_bias_attr(
l2_decay=fc_decay, k=in_channels, name='ctc_fc')
self.fc = nn.Linear(
in_channels,
out_channels,
weight_attr=weight_attr,
bias_attr=bias_attr,
name='ctc_fc')
self.out_channels = out_channels
def forward(self, x, labels=None):
predicts = self.fc(x)
if not self.training:
predicts = F.softmax(predicts, axis=2)
return predicts