diff --git a/cmake/flags.cmake b/cmake/flags.cmake
index 337db53b37fa378abef9f43c745047df0ae92212..e087770991aefc17535d50c0539c50f6316520d7 100644
--- a/cmake/flags.cmake
+++ b/cmake/flags.cmake
@@ -65,9 +65,9 @@ endif()
 set(COMMON_FLAGS
     -fPIC
     -fno-omit-frame-pointer
-#    -Wall
-#    -Wextra
-#    -Werror
+    -Wall
+    -Wextra
+    -Werror
     -Wnon-virtual-dtor
     -Wdelete-non-virtual-dtor
     -Wno-unused-parameter
diff --git a/paddle/gserver/layers/BilinearInterpLayer.cpp b/paddle/gserver/layers/BilinearInterpLayer.cpp
index 9f0c01a838562af1c77e4b5e34479e19bf4c6c86..f37efc824a2ec20161e18aefec37667496d4c5af 100644
--- a/paddle/gserver/layers/BilinearInterpLayer.cpp
+++ b/paddle/gserver/layers/BilinearInterpLayer.cpp
@@ -23,7 +23,22 @@ REGISTER_LAYER(bilinear_interp, BilinearInterpLayer);
 size_t BilinearInterpLayer::getSize() {
   inImgH_ = inputLayers_[0]->getOutput().getFrameHeight();
   inImgW_ = inputLayers_[0]->getOutput().getFrameWidth();
+
+  const BilinearInterpConfig& conf = config_.inputs(0).bilinear_interp_conf();
+  if (inImgH_ == 0) {
+    inImgH_ = conf.img_size_y();
+  }
+  if (inImgW_ == 0) {
+    inImgW_ = conf.img_size_x();
+  }
+
+  outImgH_ = conf.out_size_y();
+  outImgW_ = conf.out_size_x();
+  numChannels_ = conf.num_channels();
+
+  CHECK(outImgH_ > 0 && outImgW_ > 0);
   CHECK(inImgH_ > 0 && inImgW_ > 0);
+  CHECK(numChannels_);
 
   getOutput().setFrameHeight(outImgH_);
   getOutput().setFrameWidth(outImgW_);
@@ -37,15 +52,6 @@ bool BilinearInterpLayer::init(const LayerMap& layerMap,
 
   CHECK_EQ(1, config_.inputs_size());
 
-  const BilinearInterpConfig& conf = config_.inputs(0).bilinear_interp_conf();
-
-  outImgH_ = conf.out_size_y();
-  outImgW_ = conf.out_size_x();
-  numChannels_ = conf.num_channels();
-
-  CHECK(outImgH_ > 0 && outImgW_ > 0);
-  CHECK(numChannels_);
-
   return true;
 }
 
diff --git a/paddle/gserver/tests/test_LayerGrad.cpp b/paddle/gserver/tests/test_LayerGrad.cpp
index 8ee89992ddf1e9b8d67acb59b53a0c64af5981e7..b5b944833e47f2b874c865fe245cec900e08ad7f 100644
--- a/paddle/gserver/tests/test_LayerGrad.cpp
+++ b/paddle/gserver/tests/test_LayerGrad.cpp
@@ -40,6 +40,8 @@ TEST(Layer, BilinearInterpLayer) {
   LayerInputConfig* input = config.layerConfig.add_inputs();
   BilinearInterpConfig* bilinear = input->mutable_bilinear_interp_conf();
 
+  bilinear->set_img_size_x(32);
+  bilinear->set_img_size_y(32);
   bilinear->set_out_size_x(64);
   bilinear->set_out_size_y(64);
   bilinear->set_num_channels(4);
diff --git a/proto/ModelConfig.proto.m4 b/proto/ModelConfig.proto.m4
index 41d081942778e2bd1c11452c41825cc4eb3e1848..479b457e55a7dac58ff390cce8d67d46da3b474d 100644
--- a/proto/ModelConfig.proto.m4
+++ b/proto/ModelConfig.proto.m4
@@ -213,10 +213,13 @@ message OperatorConfig {
 }
 
 message BilinearInterpConfig {
-  // The size if output feature map.
-  required uint32 out_size_x = 1;
-  required uint32 out_size_y = 2;
-  required uint32 num_channels = 3;
+  // The size of input feature map.
+  optional uint32 img_size_x = 1;
+  optional uint32 img_size_y = 2;
+  // The size of output feature map.
+  required uint32 out_size_x = 3;
+  required uint32 out_size_y = 4;
+  required uint32 num_channels = 5;
 }
 
 message ImageConfig {