init

backend/ppocr/modeling/heads/rec_multi_head.py

@@ -0,0 +1,73 @@
+# copyright (c) 2022 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
+import paddle.nn as nn
+import paddle.nn.functional as F
+
+from ppocr.modeling.necks.rnn import Im2Seq, EncoderWithRNN, EncoderWithFC, SequenceEncoder, EncoderWithSVTR
+from .rec_ctc_head import CTCHead
+from .rec_sar_head import SARHead
+
+
+class MultiHead(nn.Layer):
+    def __init__(self, in_channels, out_channels_list, **kwargs):
+        super().__init__()
+        self.head_list = kwargs.pop('head_list')
+        self.gtc_head = 'sar'
+        assert len(self.head_list) >= 2
+        for idx, head_name in enumerate(self.head_list):
+            name = list(head_name)[0]
+            if name == 'SARHead':
+                # sar head
+                sar_args = self.head_list[idx][name]
+                self.sar_head = eval(name)(in_channels=in_channels, \
+                    out_channels=out_channels_list['SARLabelDecode'], **sar_args)
+            elif name == 'CTCHead':
+                # ctc neck
+                self.encoder_reshape = Im2Seq(in_channels)
+                neck_args = self.head_list[idx][name]['Neck']
+                encoder_type = neck_args.pop('name')
+                self.encoder = encoder_type
+                self.ctc_encoder = SequenceEncoder(in_channels=in_channels, \
+                    encoder_type=encoder_type, **neck_args)
+                # ctc head
+                head_args = self.head_list[idx][name]['Head']
+                self.ctc_head = eval(name)(in_channels=self.ctc_encoder.out_channels, \
+                    out_channels=out_channels_list['CTCLabelDecode'], **head_args)
+            else:
+                raise NotImplementedError(
+                    '{} is not supported in MultiHead yet'.format(name))
+
+    def forward(self, x, targets=None):
+        ctc_encoder = self.ctc_encoder(x)
+        ctc_out = self.ctc_head(ctc_encoder, targets)
+        head_out = dict()
+        head_out['ctc'] = ctc_out
+        head_out['ctc_neck'] = ctc_encoder
+        # eval mode
+        if not self.training:
+            return ctc_out
+        if self.gtc_head == 'sar':
+            sar_out = self.sar_head(x, targets[1:])
+            head_out['sar'] = sar_out
+            return head_out
+        else:
+            return head_out