Update crop op

paddle/fluid/operators/crop_op.cc

@@ -48,6 +48,13 @@ class CropOp : public framework::OperatorWithKernel {
       ctx->SetOutputDim("Out", y_dim);
     }
   }
+
+  framework::OpKernelType GetExpectedKernelType(
+      const framework::ExecutionContext& ctx) const override {
+    return framework::OpKernelType(
+        framework::ToDataType(ctx.Input<framework::LoDTensor>("X")->type()),
+        ctx.device_context());
+  }
 };
 
 class CropOpMaker : public framework::OpProtoAndCheckerMaker {
@@ -60,13 +67,19 @@ class CropOpMaker : public framework::OpProtoAndCheckerMaker {
              "The input used as reference for cropping, "
              "which is of the same dimensions as X.")
         .AsDispensable();
+    AddInput("Offsets",
+             "The input used to describe offsets in runtime, which is a "
+             "1-D vector whose size equals to the rank of input 'X'. The "
+             "elements data type must be int.")
+        .AsDispensable();
     AddOutput("Out",
               "The output of crop op, "
               "which is of the same dimensions as X.");
     AddAttr<std::vector<int>>("offsets",
                               "A list<int> describing offsets to be cropped. "
                               "The size of offsets list should be the same as "
-                              "the dimension size of input X.");
+                              "the dimension size of input X.")
+        .SetDefault(std::vector<int>());
     AddAttr<std::vector<int>>("shape",
                               "A list<int> describing the shape of output. "
                               "The size of shape list should be the same as "
@@ -77,6 +90,17 @@ Crop Operator.
 
 Crop input into output, as specified by offsets and shape.
 
+There are two ways to set the offsets:
+1. In runtime: Using the input 'Offsets', which is a Vairbale and can be 
+               output of other operators. This way is suitable for 
+               dynamic offsets.
+2. In network configuration: Using the attribute 'offsets', which will be 
+                             set in Python configure script. This way is 
+                             suitable for fixed offsets.
+You CANNOT use these two ways at the same time. An exception will be raised 
+if input 'Offset' is configured and meanwhile the attribute 'offsets' is 
+not empty.
+
 There are two ways to set shape:
 1. reference input: crop input X into the same shape as reference input.
                     The dimension of reference input should
@@ -146,6 +170,15 @@ class CropOpGrad : public framework::OperatorWithKernel {
       ctx->SetOutputDim(x_grad_name, x_dims);
     }
   }
+
+  framework::OpKernelType GetExpectedKernelType(
+      const framework::ExecutionContext& ctx) const override {
+    return framework::OpKernelType(
+        framework::ToDataType(
+            ctx.Input<framework::LoDTensor>(framework::GradVarName("Out"))
+                ->type()),
+        ctx.device_context());
+  }
 };
 
 }  // namespace operators

paddle/fluid/operators/crop_op.h

@@ -27,6 +27,37 @@ template <typename T, size_t D, int MajorType = Eigen::RowMajor,
 using EigenTensor = framework::EigenTensor<T, D, MajorType, IndexType>;
 using framework::Tensor;
 
+static std::vector<int> GetOffsets(const framework::ExecutionContext& ctx) {
+  std::vector<int> res;
+  int rank = ctx.Input<Tensor>("X")->dims().size();
+  if (ctx.HasInput("Offsets")) {
+    PADDLE_ENFORCE(ctx.Attr<std::vector<int>>("offsets").empty(),
+                   "Input 'Offsets' and attribute 'offsets' should not be used "
+                   "at the same time.");
+    const auto* offsets_tensor = ctx.Input<Tensor>("Offsets");
+    PADDLE_ENFORCE_EQ(offsets_tensor->dims().size(), 1);
+    PADDLE_ENFORCE_EQ(
+        rank, offsets_tensor->dims()[0],
+        "Offsets size should be equal to dimension size of input tensor.");
+    const int* offsets_data;
+    framework::Tensor cpu_tmp_tensor;
+    if (platform::is_cpu_place(offsets_tensor->place())) {
+      offsets_data = offsets_tensor->data<int>();
+    } else {
+      framework::TensorCopySync(*offsets_tensor, platform::CPUPlace(),
+                                &cpu_tmp_tensor);
+      offsets_data = cpu_tmp_tensor.data<int>();
+    }
+    res = std::vector<int>(offsets_data, offsets_data + rank);
+  } else {
+    res = ctx.Attr<std::vector<int>>("offsets");
+    PADDLE_ENFORCE_EQ(
+        rank, res.size(),
+        "Offsets size should be equal to dimension size of input tensor.");
+  }
+  return res;
+}
+
 template <typename T>
 class CropKernel : public framework::OpKernel<T> {
  public:
@@ -37,10 +68,7 @@ class CropKernel : public framework::OpKernel<T> {
     T* out_data = out->mutable_data<T>(context.GetPlace());
     auto x_stride = framework::stride(x->dims());
     auto out_stride = framework::stride(out->dims());
-    auto offsets = context.Attr<std::vector<int>>("offsets");
-    PADDLE_ENFORCE_EQ(
-        x->dims().size(), static_cast<int64_t>(offsets.size()),
-        "Offsets size should be equal to dimension size of input tensor.");
+    auto offsets = GetOffsets(context);
     int64_t offset = 0;
     for (size_t i = 0; i < offsets.size(); ++i) {
       offset += (x_stride[i] * offsets[i]);
@@ -56,7 +84,7 @@ void CropGradFunction(const framework::ExecutionContext& context) {
   if (d_x != nullptr) {
     auto* d_out = context.Input<Tensor>(framework::GradVarName("Out"));
     d_x->mutable_data<T>(context.GetPlace());
-    auto offsets = context.Attr<std::vector<int>>("offsets");
+    auto offsets = GetOffsets(context);
     Eigen::array<std::pair<int, int>, D> paddings;
     for (size_t i = 0; i < D; ++i) {
       paddings[i].first = offsets[i];

paddle/fluid/operators/random_crop_op.cc

@@ -20,7 +20,6 @@ class RandomCropOp : public framework::OperatorWithKernel {
  public:
   using framework::OperatorWithKernel::OperatorWithKernel;
 
- protected:
   framework::OpKernelType GetExpectedKernelType(
       const framework::ExecutionContext& ctx) const override {
     return framework::OpKernelType(

python/paddle/fluid/tests/unittests/test_crop_op.py

@@ -42,9 +42,9 @@ class TestCropOp(OpTest):
     def setUp(self):
         self.op_type = "crop"
         self.crop_by_input = False
+        self.offset_by_input = False
         self.attrs = {}
         self.initTestCase()
-        self.attrs['offsets'] = self.offsets
         if self.crop_by_input:
             self.inputs = {
                 'X': np.random.random(self.x_shape).astype("float32"),
@@ -55,6 +55,10 @@ def setUp(self):
             self.inputs = {
                 'X': np.random.random(self.x_shape).astype("float32"),
             }
+        if self.offset_by_input:
+            self.inputs['Offsets'] = np.array(self.offsets).astype('int32')
+        else:
+            self.attrs['offsets'] = self.offsets
         self.outputs = {
             'Out': crop(self.inputs['X'], self.offsets, self.crop_shape)
         }
@@ -101,5 +105,22 @@ def initTestCase(self):
         self.crop_by_input = True
 
 
+class TestCase5(TestCropOp):
+    def initTestCase(self):
+        self.x_shape = (3, 4, 5)
+        self.crop_shape = [2, 2, 3]
+        self.offsets = [1, 0, 2]
+        self.offset_by_input = True
+
+
+class TestCase6(TestCropOp):
+    def initTestCase(self):
+        self.x_shape = (10, 9, 14)
+        self.crop_shape = [3, 3, 5]
+        self.offsets = [3, 5, 4]
+        self.crop_by_input = True
+        self.offset_by_input = True
+
+
 if __name__ == '__main__':
     unittest.main()