TFL MCU: Move reference ResizeNearestNeighbor implementation into its own file.

so that we won't need to import all the dependencies.

This CL simply copies the existing code into the new file.

PiperOrigin-RevId: 306480426
Change-Id: I672a14c3edeeab975b5e75c18d632c8d71ecead4

tensorflow/lite/kernels/internal/BUILD

@@ -472,6 +472,7 @@ cc_library(
         "reference/reduce.h",
         "reference/reference_ops.h",
         "reference/requantize.h",
+        "reference/resize_nearest_neighbor.h",
         "reference/round.h",
         "reference/softmax.h",
         "reference/sparse_ops/fully_connected.h",
@@ -541,6 +542,7 @@ cc_library(
         "reference/reduce.h",
         "reference/reference_ops.h",
         "reference/requantize.h",
+        "reference/resize_nearest_neighbor.h",
         "reference/round.h",
         "reference/softmax.h",
         "reference/strided_slice.h",

tensorflow/lite/kernels/internal/reference/reference_ops.h

@@ -53,6 +53,7 @@ limitations under the License.
 #include "tensorflow/lite/kernels/internal/reference/quantize.h"
 #include "tensorflow/lite/kernels/internal/reference/reduce.h"
 #include "tensorflow/lite/kernels/internal/reference/requantize.h"
+#include "tensorflow/lite/kernels/internal/reference/resize_nearest_neighbor.h"
 #include "tensorflow/lite/kernels/internal/reference/round.h"
 #include "tensorflow/lite/kernels/internal/reference/softmax.h"
 #include "tensorflow/lite/kernels/internal/reference/strided_slice.h"
@@ -2459,60 +2460,6 @@ inline void BroadcastPow4DSlow(const RuntimeShape& unextended_input1_shape,
   }
 }
 
-template <typename T>
-inline void ResizeNearestNeighbor(
-    const tflite::ResizeNearestNeighborParams& op_params,
-    const RuntimeShape& unextended_input_shape, const T* input_data,
-    const RuntimeShape& output_size_shape, const int32* output_size_data,
-    const RuntimeShape& unextended_output_shape, T* output_data) {
-  // Align corners = true is not supported.
-  TFLITE_DCHECK(!op_params.align_corners);
-  TFLITE_DCHECK_LE(unextended_input_shape.DimensionsCount(), 4);
-  TFLITE_DCHECK_LE(unextended_output_shape.DimensionsCount(), 4);
-
-  const RuntimeShape input_shape =
-      RuntimeShape::ExtendedShape(4, unextended_input_shape);
-  const RuntimeShape output_shape =
-      RuntimeShape::ExtendedShape(4, unextended_output_shape);
-
-  int32 batches = MatchingDim(input_shape, 0, output_shape, 0);
-  int32 input_height = input_shape.Dims(1);
-  int32 input_width = input_shape.Dims(2);
-  int32 depth = MatchingDim(input_shape, 3, output_shape, 3);
-
-  // The Tensorflow version of this op allows resize on the width and height
-  // axis only.
-  TFLITE_DCHECK_EQ(output_size_shape.FlatSize(), 2);
-  int32 output_height = output_size_data[0];
-  int32 output_width = output_size_data[1];
-
-  // We use float to ensure agreement with the Tensorflow implementation.
-  const float height_scale = static_cast<float>(input_height) / output_height;
-  const float width_scale = static_cast<float>(input_width) / output_width;
-
-  const int col_offset = input_shape.Dims(3);
-  const int row_offset = input_shape.Dims(2) * col_offset;
-  const int batch_offset = input_shape.Dims(1) * row_offset;
-
-  const T* input_ptr = input_data;
-  T* output_ptr = output_data;
-  for (int b = 0; b < batches; ++b) {
-    for (int y = 0; y < output_height; ++y) {
-      int32 in_y = std::min(static_cast<int32>(std::floor(y * height_scale)),
-                            input_height - 1);
-      const T* y_input_ptr = input_ptr + in_y * row_offset;
-      for (int x = 0; x < output_width; ++x) {
-        int32 in_x = std::min(static_cast<int32>(std::floor(x * width_scale)),
-                              input_width - 1);
-        const T* x_input_ptr = y_input_ptr + in_x * col_offset;
-        memcpy(output_ptr, x_input_ptr, depth * sizeof(T));
-        output_ptr += depth;
-      }
-    }
-    input_ptr += batch_offset;
-  }
-}
-
 template <typename T>
 void Fill(const RuntimeShape& value_shape, const T* value_data,
           const RuntimeShape& output_shape, T* output_data) {

tensorflow/lite/kernels/internal/reference/resize_nearest_neighbor.h

@@ -0,0 +1,83 @@
+/* Copyright 2020 The TensorFlow 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.
+==============================================================================*/
+#ifndef TENSORFLOW_LITE_KERNELS_INTERNAL_REFERENCE_RESIZE_NEAREST_NEIGHBOR_H_
+#define TENSORFLOW_LITE_KERNELS_INTERNAL_REFERENCE_RESIZE_NEAREST_NEIGHBOR_H_
+
+#include <cmath>
+
+#include "tensorflow/lite/kernels/internal/types.h"
+
+namespace tflite {
+
+namespace reference_ops {
+
+template <typename T>
+inline void ResizeNearestNeighbor(
+    const tflite::ResizeNearestNeighborParams& op_params,
+    const RuntimeShape& unextended_input_shape, const T* input_data,
+    const RuntimeShape& output_size_shape, const int32* output_size_data,
+    const RuntimeShape& unextended_output_shape, T* output_data) {
+  // Align corners = true is not supported.
+  TFLITE_DCHECK(!op_params.align_corners);
+  TFLITE_DCHECK_LE(unextended_input_shape.DimensionsCount(), 4);
+  TFLITE_DCHECK_LE(unextended_output_shape.DimensionsCount(), 4);
+
+  const RuntimeShape input_shape =
+      RuntimeShape::ExtendedShape(4, unextended_input_shape);
+  const RuntimeShape output_shape =
+      RuntimeShape::ExtendedShape(4, unextended_output_shape);
+
+  int32 batches = MatchingDim(input_shape, 0, output_shape, 0);
+  int32 input_height = input_shape.Dims(1);
+  int32 input_width = input_shape.Dims(2);
+  int32 depth = MatchingDim(input_shape, 3, output_shape, 3);
+
+  // The Tensorflow version of this op allows resize on the width and height
+  // axis only.
+  TFLITE_DCHECK_EQ(output_size_shape.FlatSize(), 2);
+  int32 output_height = output_size_data[0];
+  int32 output_width = output_size_data[1];
+
+  // We use float to ensure agreement with the Tensorflow implementation.
+  const float height_scale = static_cast<float>(input_height) / output_height;
+  const float width_scale = static_cast<float>(input_width) / output_width;
+
+  const int col_offset = input_shape.Dims(3);
+  const int row_offset = input_shape.Dims(2) * col_offset;
+  const int batch_offset = input_shape.Dims(1) * row_offset;
+
+  const T* input_ptr = input_data;
+  T* output_ptr = output_data;
+  for (int b = 0; b < batches; ++b) {
+    for (int y = 0; y < output_height; ++y) {
+      int32 in_y = std::min(static_cast<int32>(std::floor(y * height_scale)),
+                            input_height - 1);
+      const T* y_input_ptr = input_ptr + in_y * row_offset;
+      for (int x = 0; x < output_width; ++x) {
+        int32 in_x = std::min(static_cast<int32>(std::floor(x * width_scale)),
+                              input_width - 1);
+        const T* x_input_ptr = y_input_ptr + in_x * col_offset;
+        memcpy(output_ptr, x_input_ptr, depth * sizeof(T));
+        output_ptr += depth;
+      }
+    }
+    input_ptr += batch_offset;
+  }
+}
+
+}  // namespace reference_ops
+}  // namespace tflite
+
+#endif  // TENSORFLOW_LITE_KERNELS_INTERNAL_REFERENCE_RESIZE_NEAREST_NEIGHBOR_H_