Add SELU & PReLU support

Dragon/include/core/common.h

@@ -17,6 +17,7 @@
 #include <map>
 #include <unordered_map>
 #include <unordered_set>
+#include <algorithm>
 #include <mutex>
 
 #include "core/types.h"

Dragon/include/operators/activation/prelu_op.h

+// --------------------------------------------------------
+// Dragon
+// Copyright(c) 2017 SeetaTech
+// Written by Ting Pan
+// --------------------------------------------------------
+
+#ifndef DRAGON_OPERATORS_ACTIVATION_PRELU_OP_H_
+#define DRAGON_OPERATORS_ACTIVATION_PRELU_OP_H_
+
+#include "core/operator.h"
+
+namespace dragon {
+
+template <class Context>
+class PReluOp : public Operator<Context> {
+ public:
+    PReluOp(const OperatorDef& op_def, Workspace* ws)
+        : Operator<Context>(op_def, ws),
+          channel_shared(OperatorBase::GetSingleArg<bool>("channel_shared", false)),
+          data_format(OperatorBase::GetSingleArg<string>("data_format", "NCHW")) {}
+
+    void RunOnDevice() override;
+    template <typename T> void RunWithType();
+
+ protected:
+    bool channel_shared;
+    string data_format;
+    TIndex channels, dim;
+};
+
+template <class Context>
+class PReluGradientOp : public Operator<Context> {
+ public:
+    PReluGradientOp(const OperatorDef& op_def, Workspace* ws)
+        : Operator<Context>(op_def, ws),
+          channel_shared(OperatorBase::GetSingleArg<bool>("channel_shared", false)),
+          data_format(OperatorBase::GetSingleArg<string>("data_format", "NCHW")) {}
+
+    void RunOnDevice() override;
+    template <typename T> void RunWithType();
+
+ protected:
+    bool channel_shared;
+    string data_format;
+    TIndex channels, dim;
+    Tensor* bcast_dw, *multiplier;
+};
+
+}    // namespace dragon
+
+#endif    // DRAGON_OPERATORS_ACTIVATION_PRELU_OP_H_
\ No newline at end of file

Dragon/include/operators/activation/selu_op.h

+// --------------------------------------------------------
+// Dragon
+// Copyright(c) 2017 SeetaTech
+// Written by Ting Pan
+// --------------------------------------------------------
+
+#ifndef DRAGON_OPERATORS_ACTIVATION_SELU_OP_H_
+#define DRAGON_OPERATORS_ACTIVATION_SELU_OP_H_
+
+#include "core/operator.h"
+
+namespace dragon {
+
+template <class Context>
+class SEluOp : public Operator<Context> {
+ public:
+    SEluOp(const OperatorDef& op_def, Workspace* ws)
+        : Operator<Context>(op_def, ws) {}
+
+    void RunOnDevice() override;
+    template <typename T> void RunWithType();
+};
+
+template <class Context>
+class SEluGradientOp : public Operator<Context> {
+ public:
+    SEluGradientOp(const OperatorDef& op_def, Workspace* ws)
+        : Operator<Context>(op_def, ws) {
+        DISABLE_SHARE_GRADIENT;
+    }
+
+    void RunOnDevice() override;
+    template <typename T> void RunWithType();
+};
+
+}    // namespace dragon
+
+#endif    // DRAGON_OPERATORS_ACTIVATION_SELU_OP_H_
\ No newline at end of file

Dragon/include/operators/vision/roi_align_op.h

@@ -29,7 +29,7 @@ class ROIAlignOp : public Operator<Context> {
  protected:
     int pool_h, pool_w;
     float spatial_scale;
-    Tensor* mask_h, *mask_w;
+    Tensor* mask;
 };
 
 template <class Context>
@@ -51,7 +51,7 @@ class ROIAlignGradientOp : public Operator<Context> {
  protected:
     int pool_h, pool_w;
     float spatial_scale;
-    Tensor* mask_h, *mask_w;
+    Tensor* mask;
 };
 
 }    // namespace dragon

Dragon/include/utils/op_kernel.h

@@ -49,6 +49,42 @@ void EluGrad(const int count,
              const float alpha,
              T* dx);
 
+/******************** activation.prelu ********************/
+
+template <typename T, class Context>
+void PRelu(const int count,
+           const int channels,
+           const int dim,
+           const bool channel_shared,
+           const string& data_format,
+           const T* x, 
+           const T* w,
+           T* y);
+
+template <typename T, class Context>
+void PReluGrad(const int count,
+               const int channels,
+               const int dim,
+               const bool channel_shared,
+               const string& data_format,
+               const T* dy,
+               const T* x,
+               const T* w,
+               T* dx);
+
+template <typename T, class Context>
+void PReluWGrad(const int rows,
+                const int row_offset,
+                const int channels,
+                const int dim,
+                const bool channel_shared,
+                const string& data_format,
+                const T* dy,
+                const T* x,
+                const T* multiplier,
+                T* bcast_dw,
+                T* dw);
+
 /******************** activation.relu ********************/
 
 template <typename T, class Context>
@@ -61,6 +97,14 @@ void ReluGrad(const int count,
               const float slope,
               T* dx);
 
+/******************** activation.selu ********************/
+
+template <typename T, class Context>
+void SElu(const int count, const T* x, T* y);
+
+template <typename T, class Context>
+void SEluGrad(const int count, const T* dy, const T* y, T* dx);
+
 /******************** activation.sigmoid ********************/
 
 template <typename T, class Context>
@@ -745,8 +789,7 @@ void ROIAlign(const float spatial_scale,
               const int pool_w,
               Tensor* x,
               Tensor* roi,
-              Tensor* mask_h,
-              Tensor* mask_y,
+              Tensor* mask,
               Tensor* y);
 
 template <typename T, class Context>
@@ -755,8 +798,7 @@ void ROIAlignGrad(const float spatial_scale,
                   const int pool_w,
                   Tensor* dy,
                   Tensor* roi,
-                  Tensor* mask_h,
-                  Tensor* mask_y,
+                  Tensor* mask,
                   Tensor* dx);
 
 }    // namespace kernel

Dragon/python/dragon/config.py

@@ -243,3 +243,24 @@ def SetLoggingLevel(level):
         'ERROR': logging.ERROR,
         'FATAL': logging.CRITICAL
     }[level])
+
+
+def SetLoggingFile(log_file):
+    """Redirect the logging into the specific file.
+
+    Parameters
+    ----------
+    log_file : str
+        The file for logging.
+
+    Notes
+    -----
+    The function will disable all possible logging at the terminal.
+
+    """
+    global logger
+    new_logger = logging.getLogger('dragon_filehandler')
+    new_logger.setLevel(logger.level)
+    file_handler = logging.FileHandler(log_file, mode="w", encoding="UTF-8")
+    new_logger.addHandler(file_handler)
+    logger = new_logger
\ No newline at end of file

Dragon/python/dragon/core/workspace.py

@@ -14,7 +14,6 @@ import dragon.protos.dragon_pb2 as pb
 import numpy as np
 import os
 from dragon import *
-from dragon.config import logger
 from google.protobuf.message import Message
 from six.moves import range as xrange
 
@@ -339,7 +338,7 @@ def LogMetaGraph(meta_graph):
     None
 
     """
-    from dragon.config import option
+    from dragon.config import option, logger
     if option['log_meta_graph']:
         logger.info(meta_graph)
 
@@ -358,11 +357,12 @@ def GetOptimizedGraph(meta_graph):
         The definition of optimized graph.
 
     """
+    from dragon.config import logger
     graph_name = meta_graph.name
     graph_tensor = 'GraphDef_' + graph_name
 
     if not HasTensorCC(graph_tensor):
-        logger.info('graph: {} does not exist, ignore printing....'.format(graph_name))
+        logger.info('Graph({}) does not exist, ignore printing....'.format(graph_name))
         return
 
     opt_graph_def = pb.GraphDef()
@@ -383,7 +383,7 @@ def LogOptimizedGraph(meta_graph):
     None
 
     """
-    from dragon.config import option
+    from dragon.config import option, logger
     if option['log_optimized_graph']:
         optimized_graph = GetOptimizedGraph(meta_graph)
         logger.info(optimized_graph)
@@ -404,7 +404,7 @@ def ExportMetaGraph(meta_graph):
     None
 
     """
-    from dragon.config import option
+    from dragon.config import option, logger
     if option['export_meta_graph']:
         if not os.path.exists(option['export_meta_graph']):
             try:
@@ -445,6 +445,7 @@ def Snapshot(tensors, filename, prefix='', suffix='.bin', format='default'):
     Available formats: ['default', 'caffe'].
 
     """
+    from dragon.config import logger
     filepath = prefix + filename + suffix
     if mpi.Is_Init():
         if not mpi.AllowSnapshot(): return
@@ -488,6 +489,7 @@ def Restore(filepath, format='default'):
     Available formats: ['default', 'caffe'].
 
     """
+    from dragon.config import logger
     assert os.path.exists(filepath), 'model of path({}) does not exist.'.format(filepath)
     if format == 'default':
         content = cPickle.load(open(filepath, 'rb'))

Dragon/python/dragon/docs/contents/config.rst

@@ -22,6 +22,7 @@ List                    Brief
 `LogOptimizedGraph`_    Enable to log optimized graph globally.
 `ExportMetaGraph`_      Enable to export all runnable meta graphs into text files.
 `SetLoggingLevel`_      Set the minimum level of Logging.
+`SetLoggingFile`_       Redirect the logging into the specific file.
 ====================    =============================================================================
 
 API Reference
@@ -41,3 +42,4 @@ API Reference
 .. _LogOptimizedGraph: #dragon.config.LogOptimizedGraph
 .. _ExportMetaGraph: #dragon.config.ExportMetaGraph
 .. _SetLoggingLevel: #dragon.config.SetLoggingLevel
+.. _SetLoggingFile: #dragon.config.SetLoggingFile
\ No newline at end of file

Dragon/python/dragon/docs/contents/operators/activation.rst

@@ -12,11 +12,15 @@
 
 .. |tanh_function| mathmacro:: \, y = \frac{e^{x} - e^{-x}}{e^{x} + e^{-x}}
 
-.. |relu_function| mathmacro:: \, y = \max(0, x)
+.. |relu_function| mathmacro:: \, y = \left\{ \begin{array} \\ x & & (x > 0) \\ 0 & & (x <= 0) \\ \end{array} \right.
+
+.. |lrelu_function| mathmacro::  \, y = \left\{ \begin{array} \\ x & & (x > 0) \\ Slope * x & & (x <= 0) \\ \end{array} \right.
+
+.. |prelu_function| mathmacro:: \, y_{i} = \left\{ \begin{array} \\ x_{i} & & (x_{i} > 0) \\ \alpha_{i} * x_{i} & & (x <= 0) \\ \end{array} \right.
 
 .. |elu_function| mathmacro:: \, y = \left\{ \begin{array} \\ x & & (x > 0) \\ Alpha * (e^{x} - 1) & & (x <= 0) \\ \end{array} \right.
 
-.. |leaky_relu_function| mathmacro:: \, y = \max(x, 0) + Slope * \min(x, 0)
+.. |selu_function| mathmacro:: \, y = 1.0507 \left\{ \begin{array} \\ x & & (x > 0) \\ 1.6733 * (e^{x} - 1) & & (x <= 0) \\ \end{array} \right.
 
 .. |dropout_function| mathmacro:: \, y = x * Bernoulli(p=1 - prob)
 

Dragon/python/dragon/docs/contents/ops.rst

@@ -61,7 +61,9 @@ List               Brief
 `Tanh`_            Tanh function.
 `Relu`_            Rectified Linear Unit function, introduces by `[Nair & Hinton, 2010] <http://www.csri.utoronto.ca/~hinton/absps/reluICML.pdf>`_.
 `LRelu`_           Leaky Rectified Linear Unit function.
+`PRelu`_           Parametric Rectified Linear Unit function, introduces by `[He et.al, 2015] <https://arxiv.org/abs/1502.01852>`_.
 `Elu`_             Exponential Linear Unit function, introduces by `[Clevert et.al, 2015] <https://arxiv.org/abs/1511.07289>`_.
+`SElu`_            Scaled Exponential Linear Unit function, introduces by `[Klambauer et.al, 2017] <https://arxiv.org/abs/1706.02515>`_.
 `Softmax`_         Softmax function.
 `Dropout`_         Randomly set a unit into zero, introduced by `[Srivastava et.al, 2014] <http://jmlr.org/papers/v15/srivastava14a.html>`_.
 ===============    ======================================================================
@@ -209,7 +211,9 @@ List                 Brief
 .. _Tanh: operators/activation.html#dragon.operators.activation.Tanh
 .. _Relu: operators/activation.html#dragon.operators.activation.Relu
 .. _LRelu: operators/activation.html#dragon.operators.activation.LRelu
+.. _PRelu: operators/activation.html#dragon.operators.activation.PRelu
 .. _Elu: operators/activation.html#dragon.operators.activation.Elu
+.. _SElu: operators/activation.html#dragon.operators.activation.SElu
 .. _Softmax: operators/activation.html#dragon.operators.activation.Softmax
 .. _Dropout: operators/activation.html#dragon.operators.activation.Dropout
 

Dragon/python/dragon/docs/contents/vm/caffe/layer.rst

@@ -42,7 +42,9 @@ Neuron
 List                    Brief
 ====================    =============================================================================
 `ReLULayer`_            The implementation of ``ReLULayer``.
+`PReLULayer`_           The implementation of ``PReLULayer``.
 `ELULayer`_             The implementation of ``ELULayer``.
+`SELULayer`_            The implementation of ``SELULayer``.
 `SigmoidLayer`_         The implementation of ``SigmoidLayer``.
 `TanHLayer`_            The implementation of ``TanHLayer``.
 `DropoutLayer`_         The implementation of ``DropoutLayer``.
@@ -154,7 +156,9 @@ API Reference
 .. _BilinearResizeLayer: #dragon.vm.caffe.layers.vision.BilinearResizeLayer
 
 .. _ReLULayer: #dragon.vm.caffe.layers.neuron.ReLULayer
+.. _PReLULayer: #dragon.vm.caffe.layers.neuron.PReLULayer
 .. _ELULayer: #dragon.vm.caffe.layers.neuron.ELULayer
+.. _SELULayer: #dragon.vm.caffe.layers.neuron.SELULayer
 .. _SigmoidLayer: #dragon.vm.caffe.layers.neuron.SigmoidLayer
 .. _TanHLayer: #dragon.vm.caffe.layers.neuron.TanHLayer
 .. _DropoutLayer: #dragon.vm.caffe.layers.neuron.DropoutLayer
@@ -232,6 +236,8 @@ API Reference
 .. _ResizeParameter.fy: https://github.com/neopenx/Dragon/tree/master/Dragon/python/dragon/vm/caffe/proto/caffe.proto#L1466
 
 .. _ReLUParameter.negative_slope: https://github.com/BVLC/caffe/blob/effcdb0b62410b2a6a54f18f23cf90733a115673/src/caffe/proto/caffe.proto#L1000
+.. _PReLUParameter.filler: https://github.com/BVLC/caffe/blob/effcdb0b62410b2a6a54f18f23cf90733a115673/src/caffe/proto/caffe.proto#L1409
+.. _PReLUParameter.channel_shared: https://github.com/BVLC/caffe/blob/effcdb0b62410b2a6a54f18f23cf90733a115673/src/caffe/proto/caffe.proto#L1411
 .. _ELUParameter.alpha: https://github.com/BVLC/caffe/blob/effcdb0b62410b2a6a54f18f23cf90733a115673/src/caffe/proto/caffe.proto#L717
 .. _DropoutParameter.dropout_ratio: https://github.com/BVLC/caffe/blob/effcdb0b62410b2a6a54f18f23cf90733a115673/src/caffe/proto/caffe.proto#L676
 .. _DropoutParameter.scale_train: https://github.com/rbgirshick/caffe-fast-rcnn/blob/0dcd397b29507b8314e252e850518c5695efbb83/src/caffe/proto/caffe.proto#L638

Dragon/python/dragon/io/blob_fetcher.py

@@ -8,8 +8,6 @@ import numpy as np
 from multiprocessing import Process
 from six.moves import range as xrange
 
-from dragon.config import logger
-
 from .utils import GetProperty
 
 class BlobFetcher(Process):
@@ -40,6 +38,7 @@ class BlobFetcher(Process):
         self.daemon = True
 
         def cleanup():
+            from dragon.config import logger
             logger.info('Terminating BlobFetcher......')
             self.terminate()
             self.join()

Dragon/python/dragon/io/data_batch.py

@@ -10,7 +10,6 @@ from multiprocessing import Queue
 from six.moves import range as xrange
 
 import dragon.core.mpi as mpi
-from dragon.config import logger
 
 from .data_reader import DataReader
 from .data_transformer import DataTransformer
@@ -171,6 +170,7 @@ class DataBatch(object):
         """
         Print I/O Information.
         """
+        from dragon.config import logger
         logger.info('---------------------------------------------------------')
         logger.info('BatchReader, Using config:')
         params = {'prefetching': self._prefetch,

Dragon/python/dragon/io/data_reader.py

@@ -9,7 +9,6 @@ import numpy.random as npr
 from multiprocessing import Process
 
 import dragon.config as config
-from dragon.config import logger
 from dragon.tools.db import LMDB
 
 from .utils import GetProperty
@@ -55,6 +54,7 @@ class DataReader(Process):
         self.daemon = True
 
         def cleanup():
+            from dragon.config import logger
             logger.info('Terminating DataReader......')
             self.terminate()
             self.join()

Dragon/python/dragon/io/data_transformer.py

@@ -9,7 +9,6 @@ import numpy.random as npr
 from multiprocessing import Process
 
 import dragon.config as config
-from dragon.config import logger
 import dragon.vm.caffe.proto.caffe_pb2 as pb
 
 from .utils import GetProperty
@@ -72,6 +71,7 @@ class DataTransformer(Process):
         self.daemon = True
 
         def cleanup():
+            from dragon.config import logger
             logger.info('Terminating DataTransformer......')
             self.terminate()
             self.join()

Dragon/python/dragon/operators/activation.py

@@ -44,7 +44,7 @@ def LRelu(inputs, slope=0.2, **kwargs):
     Returns
     -------
     Tensor
-        The output tensor, calculated as: |leaky_relu_function|.
+        The output tensor, calculated as: |lrelu_function|.
 
     """
     CheckInputs(inputs, 1)
@@ -58,6 +58,35 @@ def LRelu(inputs, slope=0.2, **kwargs):
     return output
 
 
+def PRelu(inputs, channel_shared=False, data_format='NCHW', **kwargs):
+    """Parametric Rectified Linear Unit function, introduces by `[He et.al, 2015] <https://arxiv.org/abs/1502.01852>`_.
+
+    Parameters
+    ----------
+    inputs : list of Tensor
+        The input and trainable parameter(slope).
+    channel_shared : boolean
+        Whether to share the parameter(slope) across channels.
+    data_format : str
+        The data format, ``NCHW`` or ``NHWC``.
+
+    Returns
+    -------
+    Tensor
+        The output tensor, calculated as: |prelu_function|
+
+    """
+    CheckInputs(inputs, 2)
+    arguments = ParseArguments(locals())
+
+    output = Tensor.CreateOperator(nout=1, op_type='PRelu', **arguments)
+
+    if inputs[0].shape is not None:
+        output.shape = inputs[0].shape[:]
+
+    return output
+
+
 def Elu(inputs, alpha=1.0, **kwargs):
     """Exponential Linear Unit function, introduces by `[Clevert et.al, 2015] <https://arxiv.org/abs/1511.07289>`_.
 
@@ -65,6 +94,8 @@ def Elu(inputs, alpha=1.0, **kwargs):
     ----------
     inputs : Tensor
         The input tensor.
+    alpha : float
+        The alpha.
 
     Returns
     -------
@@ -83,6 +114,31 @@ def Elu(inputs, alpha=1.0, **kwargs):
     return output
 
 
+def SElu(inputs, **kwargs):
+    """Scaled Exponential Linear Unit function, introduces by `[Klambauer et.al, 2017] <https://arxiv.org/abs/1706.02515>`_.
+
+    Parameters
+    ----------
+    inputs : Tensor
+        The input tensor.
+
+    Returns
+    -------
+    Tensor
+        The output tensor, calculated as: |selu_function|
+
+    """
+    CheckInputs(inputs, 1)
+    arguments = ParseArguments(locals())
+
+    output = Tensor.CreateOperator(nout=1, op_type='SElu', **arguments)
+
+    if inputs.shape is not None:
+        output.shape = inputs.shape[:]
+
+    return output
+
+
 def Sigmoid(inputs, **kwargs):
     """Sigmoid function.
 

Dragon/python/dragon/operators/vision.py

@@ -232,7 +232,7 @@ def ROIPooling(inputs, pool_h, pool_w, spatial_scale, **kwargs):
     return Tensor.CreateOperator(nout=1, op_type='ROIPooling', **arguments)
 
 
-def ROIAlign(inputs, pool_h=0, pool_w=0, spatial_scale=1.0, **arguments):
+def ROIAlign(inputs, pool_h=0, pool_w=0, spatial_scale=1.0, **kwargs):
     """Max ROIAlign, introduced by `[He et.al, 2017] <https://arxiv.org/abs/1703.06870>`_.
 
     The first dimension of input must be ``1``.

Dragon/python/dragon/ops.py

@@ -50,7 +50,9 @@ Sigmoid = act.Sigmoid
 Tanh = act.Tanh
 Relu = act.Relu
 LRelu = act.LRelu
+PRelu = act.PRelu
 Elu = act.Elu
+SElu = act.SElu
 Softmax = act.Softmax
 Dropout = act.Dropout
 

Dragon/python/dragon/updaters.py

@@ -6,7 +6,6 @@
 
 import numpy as np
 import pprint
-from dragon.config import logger
 import dragon.core.workspace as ws
 from dragon.core.tensor import Tensor
 
@@ -85,6 +84,7 @@ class BaseUpdater(object):
         """
         Print Updater Information.
         """
+        from dragon.config import logger
         logger.info('---------------------------------------------------------')
         logger.info('Optimizer: {}, Using config:'.format(self._type.split('Update')[0]))
         pprint.pprint(self._hyper_params)

Dragon/python/dragon/vm/caffe/layers/__init__.py

@@ -17,7 +17,9 @@ from .vision import ConvolutionLayer, \
                     BilinearResizeLayer
 
 from .neuron import ReLULayer, \
+                    PReLULayer, \
                     ELULayer, \
+                    SELULayer, \
                     DropoutLayer, \
                     TanHLayer, \
                     PowerLayer

Dragon/python/dragon/vm/caffe/layers/neuron.py

@@ -5,6 +5,7 @@
 # --------------------------------------------------------
 
 import dragon.ops as ops
+from dragon.core.tensor import Tensor
 
 from ..layer import Layer
 
@@ -29,6 +30,35 @@ class ReLULayer(Layer):
         return ops.Relu(input, **self._param)
 
 
+class PReLULayer(Layer):
+    """The implementation of ``PReLULayer``.
+
+    Parameters
+    ----------
+    filler : FillerParameter
+        The filler of parameter(slope). Refer `PReLUParameter.filler`_.
+    channel_shared : boolean
+       Whether to share the parameter across channels. Refer `PReLUParameter.channel_shared`_.
+
+    """
+    def __init__(self, LayerParameter):
+        super(PReLULayer, self).__init__(LayerParameter)
+        param = LayerParameter.prelu_param
+        self._param = {'channel_shared': param.channel_shared,
+                       'data_format': 'NCHW'}
+        slope = Tensor(LayerParameter.name + '@param0')
+        slope_diff = Tensor(LayerParameter.name + '@param0_grad')
+        if param.HasField('filler'):
+            self.Fill(slope, param, 'filler')
+        else:
+            slope.Constant(value=0.25)
+        self._blobs.append({'data': slope, 'diff': slope_diff})
+
+    def Setup(self, bottom):
+        super(PReLULayer, self).Setup(bottom)
+        return ops.PRelu(bottom + [blob['data'] for blob in self._blobs], **self._param)
+
+
 class ELULayer(Layer):
     """The implementation of ``ELULayer``.
 
@@ -41,7 +71,7 @@ class ELULayer(Layer):
     def __init__(self, LayerParameter):
         super(ELULayer, self).__init__(LayerParameter)
         param = LayerParameter.elu_param
-        self._param = {'alpha': param.alpha}
+        self._param = {'alpha': float(param.alpha)}
 
     def Setup(self, bottom):
         super(ELULayer, self).Setup(bottom)
@@ -49,6 +79,19 @@ class ELULayer(Layer):
         return ops.Elu(input, **self._param)
 
 
+class SELULayer(Layer):
+    """
+    The implementation of ``SELULayer``.
+    """
+    def __init__(self, LayerParameter):
+        super(SELULayer, self).__init__(LayerParameter)
+
+    def Setup(self, bottom):
+        super(SELULayer, self).Setup(bottom)
+        input = bottom[0] if isinstance(bottom, list) else bottom
+        return ops.SElu(input, **self._param)
+
+
 class SigmoidLayer(Layer):
     """
     The implementation of ``SigmoidLayer``.

Dragon/python/dragon/vm/caffe/solver.py

@@ -14,7 +14,6 @@ import dragon.tools.summary_writer as sw
 import dragon.vm.theano as theano
 from dragon.vm.caffe.proto import caffe_pb2 as pb
 
-from dragon.config import logger
 from dragon.vm.caffe.misc import root_solver
 from dragon.vm.caffe.net import Net
 from google.protobuf.text_format import Parse
@@ -172,6 +171,7 @@ class Solver(object):
         The implementation of `GetLearningRate(solver.cpp, L27)`_.
 
         """
+        from dragon.config import logger
         policy = self._param.lr_policy
 
         if policy == "step":
@@ -232,6 +232,7 @@ class Solver(object):
         The implementation of `Test(solver.cpp, L328)`_.
 
         """
+        from dragon.config import logger
         test_score = []
         output_id = []
         test_iter = self._param.test_iter[test_idx]
@@ -278,6 +279,7 @@ class Solver(object):
         The implementation of `Step(solver.cpp, L180)`_.
 
         """
+        from dragon.config import logger
         start_iter = self._iter; stop_iter = self._iter + iters
         loss_vec = []; smoothed_loss = 0
         tic = time.time()

Dragon/src/operators/activation/prelu_op.cc

+#include "operators/activation/prelu_op.h"
+#include "core/workspace.h"
+#include "utils/filler.h"
+#include "utils/math_functions.h"
+#include "utils/op_kernel.h"
+
+namespace dragon {
+
+template <class Context> template <typename T>
+void PReluOp<Context>::RunWithType() {
+    if (channel_shared) {
+        TENSOR_FILL(input(1), vector<TIndex>(1, 1));
+    } else {
+        TENSOR_FILL(input(1), vector<TIndex>(1, input(0).dim(1)));
+    }
+
+    auto* Xdata = input(0).template data<T, Context>();
+    auto* Wdata = input(1).template data<T, Context>();
+    auto* Ydata = output(0)->template mutable_data<T, Context>();
+    kernel::PRelu<T, Context>(output(0)->count(),
+                                        channels,
+                                             dim,
+                                  channel_shared,
+                                     data_format,
+                                           Xdata,
+                                           Wdata,
+                                          Ydata);
+}
+
+template <class Context>
+void PReluOp<Context>::RunOnDevice() {
+    if (data_format == "NCHW") {
+        channels = input(0).dim(1);
+        dim = input(0).count(2);
+    } else {
+        channels = input(0).dim(-1);
+        dim = input(0).count() / channels;
+    }
+    output(0)->ReshapeLike(input(0));
+
+    if (input(0).template IsType<float>()) RunWithType<float>();
+    else LOG(FATAL) << "Unsupported input types.";
+}
+
+DEPLOY_CPU(PRelu);
+#ifdef WITH_CUDA
+DEPLOY_CUDA(PRelu);
+#endif
+OPERATOR_SCHEMA(PRelu).NumInputs(2).NumOutputs(1);
+
+template <class Context> template <typename T>
+void PReluGradientOp<Context>::RunWithType() {
+    auto* Xdata = input(0).template data<T, Context>();
+    auto* dYdata = input(-1).template data<T, Context>();
+
+    if (output(1)->name() != "ignore") {
+        INIT_MULTIPLIER(multiplier, channels * dim);
+        bcast_dw = ws()->GetBuffer();
+        bcast_dw->Reshape(vector<TIndex>(1, channels * dim));
+        auto* dWdata = output(1)->template mutable_data<T, Context>();
+        auto* dWBdata = bcast_dw->template mutable_data<T, Context>();
+        kernel::PReluWGrad<T, Context>(input(0).dim(0),
+                                     input(0).count(1),
+                                              channels,
+                                                   dim,
+                                        channel_shared,
+                                           data_format,
+                                                dYdata,
+                                                 Xdata,
+               multiplier->template data<T, Context>(),
+                                               dWBdata,
+                                               dWdata);
+        ws()->ReleaseBuffer(bcast_dw);
+    }
+
+    if (output(0)->name() != "ignore") {
+        auto* Wdata = input(1).template data<T, Context>();
+        auto* dXdata = output(0)->template mutable_data<T, Context>();
+        kernel::PReluGrad<T, Context>(output(0)->count(),
+                                                channels,
+                                                     dim,
+                                          channel_shared,
+                                             data_format,
+                                                  dYdata,
+                                                   Xdata,
+                                                   Wdata,
+                                                 dXdata);
+    }
+}
+
+template <class Context>
+void PReluGradientOp<Context>::RunOnDevice() {
+    if (data_format == "NCHW") {
+        channels = input(0).dim(1);
+        dim = input(0).count(2);
+    } else {
+        channels = input(0).dim(-1);
+        dim = input(0).count() / channels;
+    }
+
+    output(0)->ReshapeLike(input(0));
+    output(1)->ReshapeLike(input(1));
+
+    if (input(0).template IsType<float>()) RunWithType<float>();
+    else LOG(FATAL) << "Unsupported input types.";
+}
+
+DEPLOY_CPU(PReluGradient);
+#ifdef WITH_CUDA
+DEPLOY_CUDA(PReluGradient);
+#endif
+OPERATOR_SCHEMA(PReluGradient).NumInputs(3).NumOutputs(2);
+
+class GetPReluGradient final : public GradientMakerBase {
+ public:
+    GRADIENT_MAKER_CTOR(GetPReluGradient);
+    vector<OperatorDef> MakeDefs() override {
+        return SingleDef(def.type() + "Gradient", "",
+            vector<string> {I(0), I(1), GO(0)},
+            vector<string> {GI(0), GI(1)});
+    }
+};
+REGISTER_GRADIENT(PRelu, GetPReluGradient);
+
+}    // namespace dragon
\ No newline at end of file

Dragon/src/operators/activation/selu_op.cc

+#include "operators/activation/selu_op.h"
+#include "utils/math_functions.h"
+#include "utils/op_kernel.h"
+
+namespace dragon {
+
+template <class Context> template <typename T>
+void SEluOp<Context>::RunWithType() {
+    auto* Xdata = input(0).template data<T, Context>();
+    auto* Ydata = output(0)->template mutable_data<T, Context>();
+    kernel::SElu<T, Context>(output(0)->count(), Xdata, Ydata);
+}
+
+template <class Context>
+void SEluOp<Context>::RunOnDevice() {
+    output(0)->ReshapeLike(input(0));
+
+    if (input(0).template IsType<float>()) RunWithType<float>();
+    else LOG(FATAL) << "Unsupported input types.";
+}
+
+DEPLOY_CPU(SElu);
+#ifdef WITH_CUDA
+DEPLOY_CUDA(SElu);
+#endif
+OPERATOR_SCHEMA(SElu).NumInputs(1).NumOutputs(1).Inplace({ { 0, 0 } });
+
+template <class Context> template <typename T>
+void SEluGradientOp<Context>::RunWithType() {
+    auto* Ydata = input(0).template data<T, Context>();
+    auto* dYdata = input(1).template data<T, Context>();
+    auto* dXdata = output(0)->template mutable_data<T, Context>();
+    kernel::SEluGrad<T, Context>(output(0)->count(), dYdata, Ydata, dXdata);
+}
+
+template <class Context>
+void SEluGradientOp<Context>::RunOnDevice() {
+    output(0)->ReshapeLike(input(0));
+
+    if (input(0).template IsType<float>()) RunWithType<float>();
+    else LOG(FATAL) << "Unsupported input types.";
+}
+
+DEPLOY_CPU(SEluGradient);
+#ifdef WITH_CUDA
+DEPLOY_CUDA(SEluGradient);
+#endif
+OPERATOR_SCHEMA(SEluGradient).NumInputs(2).NumOutputs(1).Inplace({ { 1, 0 }});
+
+class GetSEluGradient final : public GradientMakerBase {
+ public:
+    GRADIENT_MAKER_CTOR(GetSEluGradient);
+    vector<OperatorDef> MakeDefs() override {
+        return SingleDef(def.type() + "Gradient", "",
+            vector<string> {O(0), GO(0)},
+            vector<string> {GI(0)});
+    }
+};
+REGISTER_GRADIENT(SElu, GetSEluGradient);
+
+}    // namespace dragon
\ No newline at end of file

Dragon/src/operators/vision/roi_align_op.cc

@@ -11,7 +11,7 @@ void ROIAlignOp<Context>::RunWithType() {
                                 pool_h, pool_w,
                                      &input(0),
                                      &input(1),
-                                mask_h, mask_w,
+                                          mask,
                                     output(0));
 }
 
@@ -20,10 +20,8 @@ void ROIAlignOp<Context>::RunOnDevice() {
     vector<TIndex> dims({input(1).dim(0), input(0).dim(1), pool_h, pool_w});
     output(0)->Reshape(dims);
 
-    mask_h = ws()->CreateTensor("_t_" + anchor() + "_roi_align_mask_h");
-    mask_h->Reshape(dims);
-    mask_w = ws()->CreateTensor("_t_" + anchor() + "_roi_align_mask_w");
-    mask_w->Reshape(dims);
+    mask = ws()->CreateTensor("_t_" + anchor() + "_roi_align_mask");
+    mask->Reshape(dims);
 
     if (input(0).template IsType<float>()) return RunWithType<float>();
     else LOG(FATAL) << "Unsupported input types.";
@@ -41,7 +39,7 @@ void ROIAlignGradientOp<Context>::RunWithType() {
                                     pool_h, pool_w,
                                         &input(-1),
                                          &input(1),
-                                    mask_h, mask_w,
+                                              mask,
                                         output(0));
 }
 
@@ -49,8 +47,7 @@ template <class Context>
 void ROIAlignGradientOp<Context>::RunOnDevice() {
     output(0)->ReshapeLike(input(0));
 
-    mask_h = ws()->GetTensor("_t_" + anchor() + "_roi_align_mask_h");
-    mask_w = ws()->GetTensor("_t_" + anchor() + "_roi_align_mask_w");
+    mask = ws()->GetTensor("_t_" + anchor() + "_roi_align_mask");
 
     if (input(0).template IsType<float>()) return RunWithType<float>();
     else LOG(FATAL) << "Unsupported input types.";
@@ -59,8 +56,7 @@ void ROIAlignGradientOp<Context>::RunOnDevice() {
 template <class Context>
 void ROIAlignGradientOp<Context>::CleanResource() {
     Operator<Context>::CleanResource(); 
-    ws()->ReleaseBuffer(mask_h, "Common", true);
-    ws()->ReleaseBuffer(mask_w, "Common", true);
+    ws()->ReleaseBuffer(mask, "Common", true);
 }
 
 DEPLOY_CPU(ROIAlignGradient);

Dragon/src/utils/op_kernel.cc

@@ -72,6 +72,124 @@ template<> void EluGrad<float, CPUContext>(const int count,
     }
 }
 
+/******************** activation.prelu ********************/
+
+template<> void PRelu<float, CPUContext>(const int count,
+                                         const int channels,
+                                         const int dim,
+                                         const bool channel_shared,
+                                         const string& data_format,
+                                         const float* x,
+                                         const float* w,
+                                         float* y) {
+    if (channel_shared) {
+#ifdef WITH_OMP
+        #pragma omp parallel for num_threads(GET_OMP_THREADS(count))
+#endif
+        for (int i = 0; i < count; ++i) {
+            y[i] = std::max(x[i], float(0)) + w[0] * std::min(x[i], float(0));
+        }
+    } else {
+        if (data_format == "NCHW") {
+#ifdef WITH_OMP
+            #pragma omp parallel for num_threads(GET_OMP_THREADS(count))
+#endif
+            for (int i = 0; i < count; ++i) {
+                int c = (i / dim) % channels;
+                y[i] = std::max(x[i], float(0)) + w[c] * std::min(x[i], float(0));
+            }
+        } else if (data_format == "NHWC") {
+#ifdef WITH_OMP
+            #pragma omp parallel for num_threads(GET_OMP_THREADS(count))
+#endif
+            for (int i = 0; i < count; ++i) {
+                int c = i % channels;
+                y[i] = std::max(x[i], float(0)) + w[c] * std::min(x[i], float(0));
+            }
+        } else LOG(FATAL) << "Unknown data format: " << data_format;
+    }
+}
+
+template<> void PReluGrad<float, CPUContext>(const int count,
+                                             const int channels, 
+                                             const int dim,
+                                             const bool channel_shared,
+                                             const string& data_format,
+                                             const float* dy,
+                                             const float* x,
+                                             const float* w,
+                                             float* dx) {
+    if (channel_shared) {
+#ifdef WITH_OMP
+        #pragma omp parallel for num_threads(GET_OMP_THREADS(count))
+#endif
+        for (int i = 0; i < count; ++i) {
+            dx[i] = dy[i] * ((x[i] > 0) + w[0] * (x[i] <= 0));
+        }
+    } else {
+        if (data_format == "NCHW") {
+#ifdef WITH_OMP
+            #pragma omp parallel for num_threads(GET_OMP_THREADS(count))
+#endif
+            for (int i = 0; i < count; ++i) {
+                int c = (i / dim) % channels;
+                dx[i] = dy[i] * ((x[i] > 0) + w[c] * (x[i] <= 0));
+            }
+        } else if (data_format == "NHWC") {
+#ifdef WITH_OMP
+            #pragma omp parallel for num_threads(GET_OMP_THREADS(count))
+#endif
+            for (int i = 0; i < count; ++i) {
+                int c = i % channels;
+                dx[i] = dy[i] * ((x[i] > 0) + w[c] * (x[i] <= 0));
+            }
+        } else LOG(FATAL) << "Unknown data format: " << data_format;
+    }
+}
+
+template<> void PReluWGrad<float, CPUContext>(const int rows,
+                                              const int row_offset,
+                                              const int channels,
+                                              const int dim,
+                                              const bool channel_shared,
+                                              const string& data_format,
+                                              const float* dy,
+                                              const float* x,
+                                              const float* multiplier,
+                                              float* bcast_dw,
+                                              float* dw) {
+    const int cdim = channels * dim;
+#ifdef WITH_OMP
+    #pragma omp parallel for num_threads(GET_OMP_THREADS(cdim))
+#endif
+    for (int i = 0; i < cdim; ++i) {
+        bcast_dw[i] = dy[i] * x[i] * (x[i] <= 0);
+        for (int n = 1; n < rows; n++) {
+            const int cur_idx = i + n * row_offset;
+            bcast_dw[i] += dy[cur_idx] * x[cur_idx] * (x[cur_idx] <= 0);
+        }
+    }
+    if (channel_shared) {
+        float w_sum = math::Dot<float, CPUContext>(channels * dim, bcast_dw, multiplier);
+        math::AddScalar<float, CPUContext>(1, w_sum, dw);
+    } else {
+        if (data_format == "NCHW") {
+            math::Gemv<float, CPUContext>(CblasNoTrans, channels, dim,
+                                                                  1.0,
+                                                 bcast_dw, multiplier,
+                                                                  1.0,
+                                                                  dw);
+        } else if (data_format == "NHWC") {
+            math::Gemv<float, CPUContext>(CblasTrans, dim, channels,
+                                                                1.0,
+                                               bcast_dw, multiplier,
+                                                                1.0,
+                                                                dw);
+
+        } else LOG(FATAL) << "Unknown data format: " << data_format;
+    }
+}
+
 /******************** activation.relu ********************/
 
 template<> void Relu<float, CPUContext>(const int count, 
@@ -99,6 +217,32 @@ template<> void ReluGrad<float, CPUContext>(const int count,
     }
 }
 
+/******************** activation.selu ********************/
+
+template<> void SElu<float, CPUContext>(const int count,
+                                        const float* x,
+                                        float* y) {
+#ifdef WITH_OMP
+    #pragma omp parallel for num_threads(GET_OMP_THREADS(count))
+#endif
+    for (int i = 0; i < count; ++i) {
+        y[i] = 1.0507 * std::max(x[i], float(0))
+             + 1.7581 * (std::exp(std::min(x[i], float(0))) - float(1));
+    }
+}
+
+template<> void SEluGrad<float, CPUContext>(const int count,
+                                            const float* dy,
+                                            const float* y,
+                                            float* dx) {
+#ifdef WITH_OMP
+    #pragma omp parallel for num_threads(GET_OMP_THREADS(count))
+#endif
+    for (int i = 0; i < count; ++i) {
+        dx[i] = y[i] > 0 ? 1.0507 * dy[i] : (1.7581 + y[i]) * dy[i];
+    }
+}
+
 /******************** activation.sigmoid ********************/
 
 template <typename T>
@@ -1824,7 +1968,7 @@ template<> void ROIAlign<float, CPUContext>(const float spatial_scale,
                                             const int pool_h, const int pool_w,
                                             Tensor* x,
                                             Tensor* roi,
-                                            Tensor* mask_h, Tensor* mask_w,
+                                            Tensor* mask,
                                             Tensor* y) {
     NOT_IMPLEMENTED;
 }
@@ -1833,7 +1977,7 @@ template<> void ROIAlignGrad<float, CPUContext>(const float spatial_scale,
                                                 const int pool_h, const int pool_w,
                                                 Tensor* dy,
                                                 Tensor* roi,
-                                                Tensor* mask_h, Tensor* mask_w,
+                                                Tensor* mask,
                                                 Tensor* dx) {
     NOT_IMPLEMENTED;
 }