diff --git a/dygraph/configs/_base_/cityscapes.yml b/dygraph/configs/_base_/cityscapes.yml
index a17f195794afb53d6ca572ee6b8e1996cf2f2ee1..bd146b66d8ce50abbaafe2b43ea9fd4498d8e99f 100644
--- a/dygraph/configs/_base_/cityscapes.yml
+++ b/dygraph/configs/_base_/cityscapes.yml
@@ -4,7 +4,7 @@ learning_rate: 0.01
 
 train_dataset:
   type: Cityscapes
-  dataset_root: data/cityscapes
+  dataset_root: /mnt/liuyi22/.cache/paddle/dataset/cityscapes
   transforms:
     - type: ResizeStepScaling
       min_scale_factor: 0.5
@@ -18,7 +18,7 @@ train_dataset:
 
 val_dataset:
   type: Cityscapes
-  dataset_root: data/cityscapes
+  dataset_root: /mnt/liuyi22/.cache/paddle/dataset/cityscapes
   transforms:
     - type: Normalize
   mode: val
diff --git a/dygraph/paddleseg/core/seg_train.py b/dygraph/paddleseg/core/seg_train.py
index 01ed64e1999ddc36cfd42acb4db28094b50cbf35..ff9cdcbcd42b2553776a673302db8199cd1f9eaa 100644
--- a/dygraph/paddleseg/core/seg_train.py
+++ b/dygraph/paddleseg/core/seg_train.py
@@ -87,7 +87,8 @@ def seg_train(model,
     out_labels = ["loss", "reader_cost", "batch_cost"]
     base_logger = callbacks.BaseLogger(period=log_iters)
     train_logger = callbacks.TrainLogger(log_freq=log_iters)
-    model_ckpt = callbacks.ModelCheckpoint(save_dir, save_params_only=False, period=save_interval_iters)
+    model_ckpt = callbacks.ModelCheckpoint(
+        save_dir, save_params_only=False, period=save_interval_iters)
     vdl = callbacks.VisualDL(log_dir=os.path.join(save_dir, "log"))
     cbks_list = [base_logger, train_logger, model_ckpt, vdl]
 
@@ -120,7 +121,7 @@ def seg_train(model,
             iter += 1
             if iter > iters:
                 break
-            
+
             logs["reader_cost"] = timer.elapsed_time()
             ############## 2 ################
             cbks.on_iter_begin(iter, logs)
@@ -136,7 +137,7 @@ def seg_train(model,
                 loss = ddp_model.scale_loss(loss)
                 loss.backward()
                 ddp_model.apply_collective_grads()
-                
+
             else:
                 logits = model(images)
                 loss = loss_computation(logits, labels, losses)
@@ -148,7 +149,7 @@ def seg_train(model,
             model.clear_gradients()
 
             logs['loss'] = loss.numpy()[0]
-            
+
             logs["batch_cost"] = timer.elapsed_time()
 
             ############## 3 ################
@@ -159,4 +160,6 @@ def seg_train(model,
 
 ############### 4 ###############
     cbks.on_train_end(logs)
-#################################
\ No newline at end of file
+
+
+#################################
diff --git a/dygraph/paddleseg/core/val.py b/dygraph/paddleseg/core/val.py
index c104b2d8bf67419c58f15ba75989720662b0a2d8..b0f408c3b96f0040d8ca0882b701c7e56315c595 100644
--- a/dygraph/paddleseg/core/val.py
+++ b/dygraph/paddleseg/core/val.py
@@ -67,7 +67,7 @@ def evaluate(model,
         pred = pred[np.newaxis, :, :, np.newaxis]
         pred = pred.astype('int64')
         mask = label != ignore_index
-
+        # To-DO Test Execution Time
         conf_mat.calculate(pred=pred, label=label, ignore=mask)
         _, iou = conf_mat.mean_iou()
 
diff --git a/dygraph/paddleseg/cvlibs/callbacks.py b/dygraph/paddleseg/cvlibs/callbacks.py
index 952c97d843fcfd8fc198d5d09f61f7f58652ec6e..e948344ae499f333e435fa41fbd8f458cb8b3e2e 100644
--- a/dygraph/paddleseg/cvlibs/callbacks.py
+++ b/dygraph/paddleseg/cvlibs/callbacks.py
@@ -13,7 +13,6 @@
 # See the License for the specific language governing permissions and
 # limitations under the License.
 
-
 import os
 import time
 
@@ -24,6 +23,7 @@ from visualdl import LogWriter
 from paddleseg.utils.progbar import Progbar
 import paddleseg.utils.logger as logger
 
+
 class CallbackList(object):
     """Container abstracting a list of callbacks.
     # Arguments
@@ -44,7 +44,7 @@ class CallbackList(object):
     def set_model(self, model):
         for callback in self.callbacks:
             callback.set_model(model)
-    
+
     def set_optimizer(self, optimizer):
         for callback in self.callbacks:
             callback.set_optimizer(optimizer)
@@ -82,6 +82,7 @@ class CallbackList(object):
     def __iter__(self):
         return iter(self.callbacks)
 
+
 class Callback(object):
     """Abstract base class used to build new callbacks.
     """
@@ -94,7 +95,7 @@ class Callback(object):
 
     def set_model(self, model):
         self.model = model
-    
+
     def set_optimizer(self, optimizer):
         self.optimizer = optimizer
 
@@ -110,18 +111,18 @@ class Callback(object):
     def on_train_end(self, logs=None):
         pass
 
-class BaseLogger(Callback):
 
+class BaseLogger(Callback):
     def __init__(self, period=10):
         super(BaseLogger, self).__init__()
         self.period = period
-    
+
     def _reset(self):
         self.totals = {}
 
     def on_train_begin(self, logs=None):
         self.totals = {}
-    
+
     def on_iter_end(self, iter, logs=None):
         logs = logs or {}
         #(iter - 1) // iters_per_epoch + 1
@@ -132,13 +133,13 @@ class BaseLogger(Callback):
                 self.totals[k] = v
 
         if iter % self.period == 0 and ParallelEnv().local_rank == 0:
-            
+
             for k in self.totals:
                 logs[k] = self.totals[k] / self.period
             self._reset()
 
-class TrainLogger(Callback):
 
+class TrainLogger(Callback):
     def __init__(self, log_freq=10):
         self.log_freq = log_freq
 
@@ -154,7 +155,7 @@ class TrainLogger(Callback):
         return result.format(*arr)
 
     def on_iter_end(self, iter, logs=None):
-       
+
         if iter % self.log_freq == 0 and ParallelEnv().local_rank == 0:
             total_iters = self.params["total_iters"]
             iters_per_epoch = self.params["iters_per_epoch"]
@@ -167,49 +168,50 @@ class TrainLogger(Callback):
             reader_cost = logs["reader_cost"]
 
             logger.info(
-                "[TRAIN] epoch={}, iter={}/{}, loss={:.4f}, lr={:.6f}, batch_cost={:.4f}, reader_cost={:.4f} | ETA {}".
-                    format(current_epoch, iter, total_iters,
-                        loss, lr, batch_cost, reader_cost, eta))
+                "[TRAIN] epoch={}, iter={}/{}, loss={:.4f}, lr={:.6f}, batch_cost={:.4f}, reader_cost={:.4f} | ETA {}"
+                .format(current_epoch, iter, total_iters, loss, lr, batch_cost,
+                        reader_cost, eta))
 
-class ProgbarLogger(Callback):
 
+class ProgbarLogger(Callback):
     def __init__(self):
         super(ProgbarLogger, self).__init__()
 
     def on_train_begin(self, logs=None):
         self.verbose = self.params["verbose"]
         self.total_iters = self.params["total_iters"]
-        self.target = self.params["total_iters"] 
+        self.target = self.params["total_iters"]
         self.progbar = Progbar(target=self.target, verbose=self.verbose)
         self.seen = 0
         self.log_values = []
-    
+
     def on_iter_begin(self, iter, logs=None):
         #self.seen = 0
         if self.seen < self.target:
             self.log_values = []
-    
+
     def on_iter_end(self, iter, logs=None):
         logs = logs or {}
         self.seen += 1
         for k in self.params['metrics']:
             if k in logs:
                 self.log_values.append((k, logs[k]))
-        
+
         #if self.verbose and self.seen < self.target and ParallelEnv.local_rank == 0:
-            #print(self.log_values)
+        #print(self.log_values)
         if self.seen < self.target:
             self.progbar.update(self.seen, self.log_values)
-            
-        
-    
+
 
 class ModelCheckpoint(Callback):
+    def __init__(self,
+                 save_dir,
+                 monitor="miou",
+                 save_best_only=False,
+                 save_params_only=True,
+                 mode="max",
+                 period=1):
 
-    def __init__(self, save_dir, monitor="miou",
-                 save_best_only=False, save_params_only=True, 
-                 mode="max", period=1):
-        
         super(ModelCheckpoint, self).__init__()
         self.monitor = monitor
         self.save_dir = save_dir
@@ -241,7 +243,7 @@ class ModelCheckpoint(Callback):
         current_save_dir = os.path.join(self.save_dir, "iter_{}".format(iter))
         current_save_dir = os.path.abspath(current_save_dir)
         #if self.iters_since_last_save % self.period and ParallelEnv().local_rank == 0:
-            #self.iters_since_last_save = 0
+        #self.iters_since_last_save = 0
         if iter % self.period == 0 and ParallelEnv().local_rank == 0:
             if self.verbose > 0:
                 print("iter {iter_num}: saving model to {path}".format(
@@ -252,11 +254,9 @@ class ModelCheckpoint(Callback):
 
             if not self.save_params_only:
                 paddle.save(self.optimizer.state_dict(), filepath)
-    
 
 
 class VisualDL(Callback):
-
     def __init__(self, log_dir="./log", freq=1):
         super(VisualDL, self).__init__()
         self.log_dir = log_dir
@@ -274,4 +274,4 @@ class VisualDL(Callback):
         self.writer.flush()
 
     def on_train_end(self, logs=None):
-        self.writer.close()
\ No newline at end of file
+        self.writer.close()
diff --git a/dygraph/paddleseg/models/danet.py b/dygraph/paddleseg/models/danet.py
new file mode 100644
index 0000000000000000000000000000000000000000..5af7668e7517ec8e8a3893806ad1e5c0b17440a3
--- /dev/null
+++ b/dygraph/paddleseg/models/danet.py
@@ -0,0 +1,217 @@
+# Copyright (c) 2020 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.
+
+import os
+
+import paddle
+import paddle.nn as nn
+import paddle.nn.functional as F
+
+from paddleseg.utils import utils
+from paddleseg.cvlibs import manager, param_init
+from paddleseg.models.common.layer_libs import ConvBNReLU
+
+
+class PAM(nn.Layer):
+    """Position attention module"""
+
+    def __init__(self, in_channels):
+        super(PAM, self).__init__()
+        mid_channels = in_channels // 8
+
+        self.query_conv = nn.Conv2d(in_channels, mid_channels, 1, 1)
+        self.key_conv = nn.Conv2d(in_channels, mid_channels, 1, 1)
+        self.value_conv = nn.Conv2d(in_channels, in_channels, 1, 1)
+
+        self.gamma = self.create_parameter(
+            shape=[1],
+            dtype='float32',
+            default_initializer=nn.initializer.Constant(0))
+
+    def forward(self, x):
+        n, _, h, w = x.shape
+
+        # query: n, h * w, c1
+        query = self.query_conv(x)
+        query = paddle.reshape(query, (n, -1, h * w))
+        query = paddle.transpose(query, (0, 2, 1))
+
+        # key: n, c1, h * w
+        key = self.key_conv(x)
+        key = paddle.reshape(key, (n, -1, h * w))
+
+        # sim: n, h * w, h * w
+        sim = paddle.bmm(query, key)
+        sim = F.softmax(sim, axis=-1)
+
+        value = self.value_conv(x)
+        value = paddle.reshape(value, (n, -1, h * w))
+        sim = paddle.transpose(sim, (0, 2, 1))
+
+        # feat: from (n, c2, h * w) -> (n, c2, h, w)
+        feat = paddle.bmm(value, sim)
+        feat = paddle.reshape(feat, (n, -1, h, w))
+
+        out = self.gamma * feat + x
+        return out
+
+
+class CAM(nn.Layer):
+    """Channel attention module"""
+
+    def __init__(self):
+        super(CAM, self).__init__()
+
+        self.gamma = self.create_parameter(
+            shape=[1],
+            dtype='float32',
+            default_initializer=nn.initializer.Constant(0))
+
+    def forward(self, x):
+        n, c, h, w = x.shape
+
+        # query: n, c, h * w
+        query = paddle.reshape(x, (n, c, h * w))
+        # key: n, h * w, c
+        key = paddle.reshape(x, (n, c, h * w))
+        key = paddle.transpose(key, (0, 2, 1))
+
+        # sim: n, c, c
+        sim = paddle.bmm(query, key)
+        # The danet author claims that this can avoid gradient divergence
+        sim = paddle.max(sim, axis=-1, keepdim=True).expand_as(sim) - sim
+        sim = F.softmax(sim, axis=-1)
+
+        # feat: from (n, c, h * w) to (n, c, h, w)
+        value = paddle.reshape(x, (n, c, h * w))
+        feat = paddle.bmm(sim, value)
+        feat = paddle.reshape(feat, (n, c, h, w))
+
+        out = self.gamma * feat + x
+        return out
+
+
+class DAHead(nn.Layer):
+    """
+    The Dual attention head.
+
+    Args:
+        num_classes(int): the unique number of target classes.
+        in_channels(tuple): the number of input channels.
+    """
+
+    def __init__(self, num_classes, in_channels=None):
+        super(DAHead, self).__init__()
+        in_channels = in_channels[-1]
+        inter_channels = in_channels // 4
+
+        self.channel_conv = ConvBNReLU(
+            in_channels, inter_channels, 3, padding=1)
+        self.position_conv = ConvBNReLU(
+            in_channels, inter_channels, 3, padding=1)
+        self.pam = PAM(inter_channels)
+        self.cam = CAM()
+        self.conv1 = ConvBNReLU(inter_channels, inter_channels, 3, padding=1)
+        self.conv2 = ConvBNReLU(inter_channels, inter_channels, 3, padding=1)
+
+        self.aux_head_pam = nn.Sequential(
+            nn.Dropout2d(0.1), nn.Conv2d(inter_channels, num_classes, 1))
+
+        self.aux_head_cam = nn.Sequential(
+            nn.Dropout2d(0.1), nn.Conv2d(inter_channels, num_classes, 1))
+
+        self.cls_head = nn.Sequential(
+            nn.Dropout2d(0.1), nn.Conv2d(inter_channels, num_classes, 1))
+
+        self.init_weight()
+
+    def forward(self, x, label=None):
+        feats = x[-1]
+        channel_feats = self.channel_conv(feats)
+        channel_feats = self.cam(channel_feats)
+        channel_feats = self.conv1(channel_feats)
+        cam_head = self.aux_head_cam(channel_feats)
+
+        position_feats = self.position_conv(feats)
+        position_feats = self.pam(position_feats)
+        position_feats = self.conv2(position_feats)
+        pam_head = self.aux_head_pam(position_feats)
+
+        feats_sum = position_feats + channel_feats
+        cam_logit = self.aux_head_cam(channel_feats)
+        pam_logit = self.aux_head_cam(position_feats)
+        logit = self.cls_head(feats_sum)
+        return [logit, cam_logit, pam_logit]
+
+    def init_weight(self):
+        """Initialize the parameters of model parts."""
+        for sublayer in self.sublayers():
+            if isinstance(sublayer, nn.Conv2d):
+                param_init.normal_init(sublayer.weight, scale=0.001)
+            elif isinstance(sublayer, nn.SyncBatchNorm):
+                param_init.constant_init(sublayer.weight, value=1)
+                param_init.constant_init(sublayer.bias, value=0)
+
+
+@manager.MODELS.add_component
+class DANet(nn.Layer):
+    """
+    The DANet implementation based on PaddlePaddle.
+
+    The original article refers to
+        Fu, jun, et al. "Dual Attention Network for Scene Segmentation"
+        (https://arxiv.org/pdf/1809.02983.pdf)
+
+    Args:
+        num_classes(int): the unique number of target classes.
+        backbone(Paddle.nn.Layer): backbone network.
+        pretrained(str): the path or url of pretrained model. Default to None.
+        backbone_indices(tuple): values in the tuple indicate the indices of output of backbone.
+                                 Only the last indice is used.
+    """
+
+    def __init__(self,
+                 num_classes,
+                 backbone,
+                 pretrained=None,
+                 backbone_indices=None):
+        super(DANet, self).__init__()
+
+        self.backbone = backbone
+        self.backbone_indices = backbone_indices
+        in_channels = [self.backbone.channels[i] for i in backbone_indices]
+
+        self.head = DAHead(num_classes=num_classes, in_channels=in_channels)
+
+        self.init_weight(pretrained)
+
+    def forward(self, x, label=None):
+        feats = self.backbone(x)
+        feats = [feats[i] for i in self.backbone_indices]
+        preds = self.head(feats, label)
+        preds = [F.resize_bilinear(pred, x.shape[2:]) for pred in preds]
+        return preds
+
+    def init_weight(self, pretrained=None):
+        """
+        Initialize the parameters of model parts.
+        Args:
+            pretrained ([str], optional): the path of pretrained model.. Defaults to None.
+        """
+        if pretrained is not None:
+            if os.path.exists(pretrained):
+                utils.load_pretrained_model(self, pretrained)
+            else:
+                raise Exception(
+                    'Pretrained model is not found: {}'.format(pretrained))
diff --git a/dygraph/paddleseg/models/ocrnet.py b/dygraph/paddleseg/models/ocrnet.py
index 61f4815347d015ad03c89269b817099c2b460120..01f7214b7077ba17f6c5bf361783af6cc58bdb8d 100644
--- a/dygraph/paddleseg/models/ocrnet.py
+++ b/dygraph/paddleseg/models/ocrnet.py
@@ -14,36 +14,41 @@
 
 import os
 
-import paddle.fluid as fluid
-from paddle.fluid.dygraph import Sequential, Conv2D
+import paddle
+import paddle.nn as nn
+import paddle.nn.functional as F
 
-from paddleseg.cvlibs import manager
-from paddleseg.models.common.layer_libs import ConvBNReLU
 from paddleseg import utils
+from paddleseg.cvlibs import manager, param_init
+from paddleseg.models.common.layer_libs import ConvBNReLU, AuxLayer
 
 
-class SpatialGatherBlock(fluid.dygraph.Layer):
+class SpatialGatherBlock(nn.Layer):
+    """Aggregation layer to compute the pixel-region representation"""
+
     def forward(self, pixels, regions):
         n, c, h, w = pixels.shape
         _, k, _, _ = regions.shape
 
         # pixels: from (n, c, h, w) to (n, h*w, c)
-        pixels = fluid.layers.reshape(pixels, (n, c, h * w))
-        pixels = fluid.layers.transpose(pixels, (0, 2, 1))
+        pixels = paddle.reshape(pixels, (n, c, h * w))
+        pixels = paddle.transpose(pixels, (0, 2, 1))
 
         # regions: from (n, k, h, w) to (n, k, h*w)
-        regions = fluid.layers.reshape(regions, (n, k, h * w))
-        regions = fluid.layers.softmax(regions, axis=2)
+        regions = paddle.reshape(regions, (n, k, h * w))
+        regions = F.softmax(regions, axis=2)
 
         # feats: from (n, k, c) to (n, c, k, 1)
-        feats = fluid.layers.matmul(regions, pixels)
-        feats = fluid.layers.transpose(feats, (0, 2, 1))
-        feats = fluid.layers.unsqueeze(feats, axes=[-1])
+        feats = paddle.bmm(regions, pixels)
+        feats = paddle.transpose(feats, (0, 2, 1))
+        feats = paddle.unsqueeze(feats, axis=-1)
 
         return feats
 
 
-class SpatialOCRModule(fluid.dygraph.Layer):
+class SpatialOCRModule(nn.Layer):
+    """Aggregate the global object representation to update the representation for each pixel"""
+
     def __init__(self,
                  in_channels,
                  key_channels,
@@ -53,30 +58,31 @@ class SpatialOCRModule(fluid.dygraph.Layer):
 
         self.attention_block = ObjectAttentionBlock(in_channels, key_channels)
         self.dropout_rate = dropout_rate
-        self.conv1x1 = Conv2D(2 * in_channels, out_channels, 1)
+        self.conv1x1 = nn.Sequential(
+            nn.Conv2d(2 * in_channels, out_channels, 1), nn.Dropout2d(0.1))
 
     def forward(self, pixels, regions):
         context = self.attention_block(pixels, regions)
-        feats = fluid.layers.concat([context, pixels], axis=1)
-
+        feats = paddle.concat([context, pixels], axis=1)
         feats = self.conv1x1(feats)
-        feats = fluid.layers.dropout(feats, self.dropout_rate)
 
         return feats
 
 
-class ObjectAttentionBlock(fluid.dygraph.Layer):
+class ObjectAttentionBlock(nn.Layer):
+    """A self-attention module."""
+
     def __init__(self, in_channels, key_channels):
         super(ObjectAttentionBlock, self).__init__()
 
         self.in_channels = in_channels
         self.key_channels = key_channels
 
-        self.f_pixel = Sequential(
+        self.f_pixel = nn.Sequential(
             ConvBNReLU(in_channels, key_channels, 1),
             ConvBNReLU(key_channels, key_channels, 1))
 
-        self.f_object = Sequential(
+        self.f_object = nn.Sequential(
             ConvBNReLU(in_channels, key_channels, 1),
             ConvBNReLU(key_channels, key_channels, 1))
 
@@ -89,127 +95,140 @@ class ObjectAttentionBlock(fluid.dygraph.Layer):
 
         # query : from (n, c1, h1, w1) to (n, h1*w1, key_channels)
         query = self.f_pixel(x)
-        query = fluid.layers.reshape(query, (n, self.key_channels, -1))
-        query = fluid.layers.transpose(query, (0, 2, 1))
+        query = paddle.reshape(query, (n, self.key_channels, -1))
+        query = paddle.transpose(query, (0, 2, 1))
 
         # key : from (n, c2, h2, w2) to (n, key_channels, h2*w2)
         key = self.f_object(proxy)
-        key = fluid.layers.reshape(key, (n, self.key_channels, -1))
+        key = paddle.reshape(key, (n, self.key_channels, -1))
 
         # value : from (n, c2, h2, w2) to (n, h2*w2, key_channels)
         value = self.f_down(proxy)
-        value = fluid.layers.reshape(value, (n, self.key_channels, -1))
-        value = fluid.layers.transpose(value, (0, 2, 1))
+        value = paddle.reshape(value, (n, self.key_channels, -1))
+        value = paddle.transpose(value, (0, 2, 1))
 
         # sim_map (n, h1*w1, h2*w2)
-        sim_map = fluid.layers.matmul(query, key)
+        sim_map = paddle.bmm(query, key)
         sim_map = (self.key_channels**-.5) * sim_map
-        sim_map = fluid.layers.softmax(sim_map, axis=-1)
+        sim_map = F.softmax(sim_map, axis=-1)
 
         # context from (n, h1*w1, key_channels) to (n , out_channels, h1, w1)
-        context = fluid.layers.matmul(sim_map, value)
-        context = fluid.layers.transpose(context, (0, 2, 1))
-        context = fluid.layers.reshape(context, (n, self.key_channels, h, w))
+        context = paddle.bmm(sim_map, value)
+        context = paddle.transpose(context, (0, 2, 1))
+        context = paddle.reshape(context, (n, self.key_channels, h, w))
         context = self.f_up(context)
 
         return context
 
 
-@manager.MODELS.add_component
-class OCRNet(fluid.dygraph.Layer):
+class OCRHead(nn.Layer):
+    """
+    The Object contextual representation head.
+    Args:
+        num_classes(int): the unique number of target classes.
+        in_channels(tuple): the number of input channels.
+        ocr_mid_channels(int): the number of middle channels in OCRHead.
+        ocr_key_channels(int): the number of key channels in ObjectAttentionBlock.
+    """
+
     def __init__(self,
                  num_classes,
-                 backbone,
-                 model_pretrained=None,
                  in_channels=None,
                  ocr_mid_channels=512,
-                 ocr_key_channels=256,
-                 ignore_index=255):
-        super(OCRNet, self).__init__()
+                 ocr_key_channels=256):
+        super(OCRHead, self).__init__()
 
-        self.ignore_index = ignore_index
         self.num_classes = num_classes
-        self.EPS = 1e-5
-
-        self.backbone = backbone
         self.spatial_gather = SpatialGatherBlock()
         self.spatial_ocr = SpatialOCRModule(ocr_mid_channels, ocr_key_channels,
                                             ocr_mid_channels)
-        self.conv3x3_ocr = ConvBNReLU(
-            in_channels, ocr_mid_channels, 3, padding=1)
-        self.cls_head = Conv2D(ocr_mid_channels, self.num_classes, 1)
 
-        self.aux_head = Sequential(
-            ConvBNReLU(in_channels, in_channels, 3, padding=1),
-            Conv2D(in_channels, self.num_classes, 1))
+        self.indices = [-2, -1] if len(in_channels) > 1 else [-1, -1]
 
-        self.init_weight(model_pretrained)
+        self.conv3x3_ocr = ConvBNReLU(
+            in_channels[self.indices[1]], ocr_mid_channels, 3, padding=1)
+        self.cls_head = nn.Conv2d(ocr_mid_channels, self.num_classes, 1)
+        self.aux_head = AuxLayer(in_channels[self.indices[0]],
+                                 in_channels[self.indices[0]], self.num_classes)
+        self.init_weight()
 
     def forward(self, x, label=None):
-        feats = self.backbone(x)
+        feat_shallow, feat_deep = x[self.indices[0]], x[self.indices[1]]
 
-        soft_regions = self.aux_head(feats)
-        pixels = self.conv3x3_ocr(feats)
+        soft_regions = self.aux_head(feat_shallow)
+        pixels = self.conv3x3_ocr(feat_deep)
 
         object_regions = self.spatial_gather(pixels, soft_regions)
         ocr = self.spatial_ocr(pixels, object_regions)
 
         logit = self.cls_head(ocr)
-        logit = fluid.layers.resize_bilinear(logit, x.shape[2:])
-
-        if self.training:
-            soft_regions = fluid.layers.resize_bilinear(soft_regions,
-                                                        x.shape[2:])
-            cls_loss = self._get_loss(logit, label)
-            aux_loss = self._get_loss(soft_regions, label)
-            return cls_loss + 0.4 * aux_loss
-
-        score_map = fluid.layers.softmax(logit, axis=1)
-        score_map = fluid.layers.transpose(score_map, [0, 2, 3, 1])
-        pred = fluid.layers.argmax(score_map, axis=3)
-        pred = fluid.layers.unsqueeze(pred, axes=[3])
-        return pred, score_map
-
-    def init_weight(self, pretrained_model=None):
+        return [logit, soft_regions]
+
+    def init_weight(self):
+        """Initialize the parameters of model parts."""
+        for sublayer in self.sublayers():
+            if isinstance(sublayer, nn.Conv2d):
+                param_init.normal_init(sublayer.weight, scale=0.001)
+            elif isinstance(sublayer, nn.SyncBatchNorm):
+                param_init.constant_init(sublayer.weight, value=1)
+                param_init.constant_init(sublayer.bias, value=0)
+
+
+@manager.MODELS.add_component
+class OCRNet(nn.Layer):
+    """
+    The OCRNet implementation based on PaddlePaddle.
+    The original article refers to
+        Yuan, Yuhui, et al. "Object-Contextual Representations for Semantic Segmentation"
+        (https://arxiv.org/pdf/1909.11065.pdf)
+    Args:
+        num_classes(int): the unique number of target classes.
+        backbone(Paddle.nn.Layer): backbone network.
+        pretrained(str): the path or url of pretrained model. Default to None.
+        backbone_indices(tuple): two values in the tuple indicate the indices of output of backbone.
+                        the first index will be taken as a deep-supervision feature in auxiliary layer;
+                        the second one will be taken as input of pixel representation.
+        ocr_mid_channels(int): the number of middle channels in OCRHead.
+        ocr_key_channels(int): the number of key channels in ObjectAttentionBlock.
+    """
+
+    def __init__(self,
+                 num_classes,
+                 backbone,
+                 pretrained=None,
+                 backbone_indices=None,
+                 ocr_mid_channels=512,
+                 ocr_key_channels=256):
+        super(OCRNet, self).__init__()
+
+        self.backbone = backbone
+        self.backbone_indices = backbone_indices
+        in_channels = [self.backbone.channels[i] for i in backbone_indices]
+
+        self.head = OCRHead(
+            num_classes=num_classes,
+            in_channels=in_channels,
+            ocr_mid_channels=ocr_mid_channels,
+            ocr_key_channels=ocr_key_channels)
+
+        self.init_weight(pretrained)
+
+    def forward(self, x, label=None):
+        feats = self.backbone(x)
+        feats = [feats[i] for i in self.backbone_indices]
+        preds = self.head(feats, label)
+        preds = [F.resize_bilinear(pred, x.shape[2:]) for pred in preds]
+        return preds
+
+    def init_weight(self, pretrained=None):
         """
         Initialize the parameters of model parts.
         Args:
-            pretrained_model ([str], optional): the path of pretrained model.. Defaults to None.
+            pretrained ([str], optional): the path of pretrained model.. Defaults to None.
         """
-        if pretrained_model is not None:
-            if os.path.exists(pretrained_model):
-                utils.load_pretrained_model(self, pretrained_model)
+        if pretrained is not None:
+            if os.path.exists(pretrained):
+                utils.load_pretrained_model(self, pretrained)
             else:
-                raise Exception('Pretrained model is not found: {}'.format(
-                    pretrained_model))
-
-    def _get_loss(self, logit, label):
-        """
-        compute forward loss of the model
-
-        Args:
-            logit (tensor): the logit of model output
-            label (tensor): ground truth
-
-        Returns:
-            avg_loss (tensor): forward loss
-        """
-        logit = fluid.layers.transpose(logit, [0, 2, 3, 1])
-        label = fluid.layers.transpose(label, [0, 2, 3, 1])
-        mask = label != self.ignore_index
-        mask = fluid.layers.cast(mask, 'float32')
-        loss, probs = fluid.layers.softmax_with_cross_entropy(
-            logit,
-            label,
-            ignore_index=self.ignore_index,
-            return_softmax=True,
-            axis=-1)
-
-        loss = loss * mask
-        avg_loss = fluid.layers.mean(loss) / (
-            fluid.layers.mean(mask) + self.EPS)
-
-        label.stop_gradient = True
-        mask.stop_gradient = True
-
-        return avg_loss
+                raise Exception(
+                    'Pretrained model is not found: {}'.format(pretrained))
\ No newline at end of file
diff --git a/dygraph/paddleseg/utils/metrics.py b/dygraph/paddleseg/utils/metrics.py
index b107cbd57a936fb909086567fc8b703fb86963b7..44eaf4ed0580699cdb0be35f53a343cb8f70b751 100644
--- a/dygraph/paddleseg/utils/metrics.py
+++ b/dygraph/paddleseg/utils/metrics.py
@@ -41,7 +41,7 @@ class ConfusionMatrix(object):
         label = np.asarray(label)[mask]
         pred = np.asarray(pred)[mask]
         one = np.ones_like(pred)
-        # Accumuate ([row=label, col=pred], 1) into sparse matrix
+        # Accumuate ([row=label, col=pred], 1) into sparse
         spm = csr_matrix((one, (label, pred)),
                          shape=(self.num_classes, self.num_classes))
         spm = spm.todense()
diff --git a/dygraph/paddleseg/utils/progbar.py b/dygraph/paddleseg/utils/progbar.py
index b5e82881abe238f2eb686e8dfd28214f70b97819..d57ce707c407b7837acb9cbd4d2ad244ff6575a7 100644
--- a/dygraph/paddleseg/utils/progbar.py
+++ b/dygraph/paddleseg/utils/progbar.py
@@ -17,8 +17,9 @@ import time
 
 import numpy as np
 
+
 class Progbar(object):
-  """Displays a progress bar.
+    """Displays a progress bar.
      refers to https://github.com/keras-team/keras/blob/keras-2/keras/utils/generic_utils.py
   Arguments:
       target: Total number of steps expected, None if unknown.
@@ -31,39 +32,39 @@ class Progbar(object):
       unit_name: Display name for step counts (usually "step" or "sample").
   """
 
-  def __init__(self,
-               target,
-               width=30,
-               verbose=1,
-               interval=0.05,
-               stateful_metrics=None,
-               unit_name='step'):
-    self.target = target
-    self.width = width
-    self.verbose = verbose
-    self.interval = interval
-    self.unit_name = unit_name
-    if stateful_metrics:
-      self.stateful_metrics = set(stateful_metrics)
-    else:
-      self.stateful_metrics = set()
-
-    self._dynamic_display = ((hasattr(sys.stdout, 'isatty') and
-                              sys.stdout.isatty()) or
-                             'ipykernel' in sys.modules or
-                             'posix' in sys.modules or
-                             'PYCHARM_HOSTED' in os.environ)
-    self._total_width = 0
-    self._seen_so_far = 0
-    # We use a dict + list to avoid garbage collection
-    # issues found in OrderedDict
-    self._values = {}
-    self._values_order = []
-    self._start = time.time()
-    self._last_update = 0
-
-  def update(self, current, values=None, finalize=None):
-    """Updates the progress bar.
+    def __init__(self,
+                 target,
+                 width=30,
+                 verbose=1,
+                 interval=0.05,
+                 stateful_metrics=None,
+                 unit_name='step'):
+        self.target = target
+        self.width = width
+        self.verbose = verbose
+        self.interval = interval
+        self.unit_name = unit_name
+        if stateful_metrics:
+            self.stateful_metrics = set(stateful_metrics)
+        else:
+            self.stateful_metrics = set()
+
+        self._dynamic_display = ((hasattr(sys.stdout, 'isatty')
+                                  and sys.stdout.isatty())
+                                 or 'ipykernel' in sys.modules
+                                 or 'posix' in sys.modules
+                                 or 'PYCHARM_HOSTED' in os.environ)
+        self._total_width = 0
+        self._seen_so_far = 0
+        # We use a dict + list to avoid garbage collection
+        # issues found in OrderedDict
+        self._values = {}
+        self._values_order = []
+        self._start = time.time()
+        self._last_update = 0
+
+    def update(self, current, values=None, finalize=None):
+        """Updates the progress bar.
     Arguments:
         current: Index of current step.
         values: List of tuples: `(name, value_for_last_step)`. If `name` is in
@@ -72,129 +73,131 @@ class Progbar(object):
         finalize: Whether this is the last update for the progress bar. If
           `None`, defaults to `current >= self.target`.
     """
-    if finalize is None:
-      if self.target is None:
-        finalize = False
-      else:
-        finalize = current >= self.target
-
-    values = values or []
-    for k, v in values:
-      if k not in self._values_order:
-        self._values_order.append(k)
-      if k not in self.stateful_metrics:
-        # In the case that progress bar doesn't have a target value in the first
-        # epoch, both on_batch_end and on_epoch_end will be called, which will
-        # cause 'current' and 'self._seen_so_far' to have the same value. Force
-        # the minimal value to 1 here, otherwise stateful_metric will be 0s.
-        value_base = max(current - self._seen_so_far, 1)
-        if k not in self._values:
-          self._values[k] = [v * value_base, value_base]
-        else:
-          self._values[k][0] += v * value_base
-          self._values[k][1] += value_base
-      else:
-        # Stateful metrics output a numeric value. This representation
-        # means "take an average from a single value" but keeps the
-        # numeric formatting.
-        self._values[k] = [v, 1]
-    self._seen_so_far = current
-
-    now = time.time()
-    info = ' - %.0fs' % (now - self._start)
-    if self.verbose == 1:
-      if now - self._last_update < self.interval and not finalize:
-        return
-
-      prev_total_width = self._total_width
-      if self._dynamic_display:
-        sys.stdout.write('\b' * prev_total_width)
-        sys.stdout.write('\r')
-      else:
-        sys.stdout.write('\n')
-
-      if self.target is not None:
-        numdigits = int(np.log10(self.target)) + 1
-        bar = ('%' + str(numdigits) + 'd/%d [') % (current, self.target)
-        prog = float(current) / self.target
-        prog_width = int(self.width * prog)
-        if prog_width > 0:
-          bar += ('=' * (prog_width - 1))
-          if current < self.target:
-            bar += '>'
-          else:
-            bar += '='
-        bar += ('.' * (self.width - prog_width))
-        bar += ']'
-      else:
-        bar = '%7d/Unknown' % current
-
-      self._total_width = len(bar)
-      sys.stdout.write(bar)
-
-      if current:
-        time_per_unit = (now - self._start) / current
-      else:
-        time_per_unit = 0
-
-      if self.target is None or finalize:
-        if time_per_unit >= 1 or time_per_unit == 0:
-          info += ' %.0fs/%s' % (time_per_unit, self.unit_name)
-        elif time_per_unit >= 1e-3:
-          info += ' %.0fms/%s' % (time_per_unit * 1e3, self.unit_name)
-        else:
-          info += ' %.0fus/%s' % (time_per_unit * 1e6, self.unit_name)
-      else:
-        eta = time_per_unit * (self.target - current)
-        if eta > 3600:
-          eta_format = '%d:%02d:%02d' % (eta // 3600,
-                                         (eta % 3600) // 60, eta % 60)
-        elif eta > 60:
-          eta_format = '%d:%02d' % (eta // 60, eta % 60)
-        else:
-          eta_format = '%ds' % eta
-
-        info = ' - ETA: %s' % eta_format
-
-      for k in self._values_order:
-        info += ' - %s:' % k
-        if isinstance(self._values[k], list):
-          avg = np.mean(self._values[k][0] / max(1, self._values[k][1]))
-          if abs(avg) > 1e-3:
-            info += ' %.4f' % avg
-          else:
-            info += ' %.4e' % avg
-        else:
-          info += ' %s' % self._values[k]
-
-      self._total_width += len(info)
-      if prev_total_width > self._total_width:
-        info += (' ' * (prev_total_width - self._total_width))
-
-      if finalize:
-        info += '\n'
-
-      sys.stdout.write(info)
-      sys.stdout.flush()
-
-    elif self.verbose == 2:
-      if finalize:
-        numdigits = int(np.log10(self.target)) + 1
-        count = ('%' + str(numdigits) + 'd/%d') % (current, self.target)
-        info = count + info
-        for k in self._values_order:
-          info += ' - %s:' % k
-          avg = np.mean(self._values[k][0] / max(1, self._values[k][1]))
-          if avg > 1e-3:
-            info += ' %.4f' % avg
-          else:
-            info += ' %.4e' % avg
-        info += '\n'
-
-        sys.stdout.write(info)
-        sys.stdout.flush()
-
-    self._last_update = now
-
-  def add(self, n, values=None):
-    self.update(self._seen_so_far + n, values)
\ No newline at end of file
+        if finalize is None:
+            if self.target is None:
+                finalize = False
+            else:
+                finalize = current >= self.target
+
+        values = values or []
+        for k, v in values:
+            if k not in self._values_order:
+                self._values_order.append(k)
+            if k not in self.stateful_metrics:
+                # In the case that progress bar doesn't have a target value in the first
+                # epoch, both on_batch_end and on_epoch_end will be called, which will
+                # cause 'current' and 'self._seen_so_far' to have the same value. Force
+                # the minimal value to 1 here, otherwise stateful_metric will be 0s.
+                value_base = max(current - self._seen_so_far, 1)
+                if k not in self._values:
+                    self._values[k] = [v * value_base, value_base]
+                else:
+                    self._values[k][0] += v * value_base
+                    self._values[k][1] += value_base
+            else:
+                # Stateful metrics output a numeric value. This representation
+                # means "take an average from a single value" but keeps the
+                # numeric formatting.
+                self._values[k] = [v, 1]
+        self._seen_so_far = current
+
+        now = time.time()
+        info = ' - %.0fs' % (now - self._start)
+        if self.verbose == 1:
+            if now - self._last_update < self.interval and not finalize:
+                return
+
+            prev_total_width = self._total_width
+            if self._dynamic_display:
+                sys.stdout.write('\b' * prev_total_width)
+                sys.stdout.write('\r')
+            else:
+                sys.stdout.write('\n')
+
+            if self.target is not None:
+                numdigits = int(np.log10(self.target)) + 1
+                bar = ('%' + str(numdigits) + 'd/%d [') % (current, self.target)
+                prog = float(current) / self.target
+                prog_width = int(self.width * prog)
+                if prog_width > 0:
+                    bar += ('=' * (prog_width - 1))
+                    if current < self.target:
+                        bar += '>'
+                    else:
+                        bar += '='
+                bar += ('.' * (self.width - prog_width))
+                bar += ']'
+            else:
+                bar = '%7d/Unknown' % current
+
+            self._total_width = len(bar)
+            sys.stdout.write(bar)
+
+            if current:
+                time_per_unit = (now - self._start) / current
+            else:
+                time_per_unit = 0
+
+            if self.target is None or finalize:
+                if time_per_unit >= 1 or time_per_unit == 0:
+                    info += ' %.0fs/%s' % (time_per_unit, self.unit_name)
+                elif time_per_unit >= 1e-3:
+                    info += ' %.0fms/%s' % (time_per_unit * 1e3, self.unit_name)
+                else:
+                    info += ' %.0fus/%s' % (time_per_unit * 1e6, self.unit_name)
+            else:
+                eta = time_per_unit * (self.target - current)
+                if eta > 3600:
+                    eta_format = '%d:%02d:%02d' % (eta // 3600,
+                                                   (eta % 3600) // 60, eta % 60)
+                elif eta > 60:
+                    eta_format = '%d:%02d' % (eta // 60, eta % 60)
+                else:
+                    eta_format = '%ds' % eta
+
+                info = ' - ETA: %s' % eta_format
+
+            for k in self._values_order:
+                info += ' - %s:' % k
+                if isinstance(self._values[k], list):
+                    avg = np.mean(
+                        self._values[k][0] / max(1, self._values[k][1]))
+                    if abs(avg) > 1e-3:
+                        info += ' %.4f' % avg
+                    else:
+                        info += ' %.4e' % avg
+                else:
+                    info += ' %s' % self._values[k]
+
+            self._total_width += len(info)
+            if prev_total_width > self._total_width:
+                info += (' ' * (prev_total_width - self._total_width))
+
+            if finalize:
+                info += '\n'
+
+            sys.stdout.write(info)
+            sys.stdout.flush()
+
+        elif self.verbose == 2:
+            if finalize:
+                numdigits = int(np.log10(self.target)) + 1
+                count = ('%' + str(numdigits) + 'd/%d') % (current, self.target)
+                info = count + info
+                for k in self._values_order:
+                    info += ' - %s:' % k
+                    avg = np.mean(
+                        self._values[k][0] / max(1, self._values[k][1]))
+                    if avg > 1e-3:
+                        info += ' %.4f' % avg
+                    else:
+                        info += ' %.4e' % avg
+                info += '\n'
+
+                sys.stdout.write(info)
+                sys.stdout.flush()
+
+        self._last_update = now
+
+    def add(self, n, values=None):
+        self.update(self._seen_so_far + n, values)