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ppocr/modeling/heads/cls_head.py

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+# copyright (c) 2020 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 nn, ParamAttr
+import paddle.nn.functional as F
+
+
+class ClsHead(nn.Layer):
+    """
+    Class orientation
+
+    Args:
+
+        params(dict): super parameters for build Class network
+    """
+
+    def __init__(self, in_channels, class_dim, **kwargs):
+        super(ClsHead, self).__init__()
+        self.pool = nn.AdaptiveAvgPool2D(1)
+        stdv = 1.0 / math.sqrt(in_channels * 1.0)
+        self.fc = nn.Linear(
+            in_channels,
+            class_dim,
+            weight_attr=ParamAttr(
+                name="fc_0.w_0", initializer=nn.initializer.Uniform(-stdv, stdv)
+            ),
+            bias_attr=ParamAttr(name="fc_0.b_0"),
+        )
+
+    def forward(self, x, targets=None):
+        x = self.pool(x)
+        x = paddle.reshape(x, shape=[x.shape[0], x.shape[1]])
+        x = self.fc(x)
+        if not self.training:
+            x = F.softmax(x, axis=1)
+        return x