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diff --git a/src/utils/reference_info.h b/src/utils/reference_info.h
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+/*
+ * Copyright 2020 The libgav1 Authors
+ *
+ * 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 LIBGAV1_SRC_UTILS_REFERENCE_INFO_H_
+#define LIBGAV1_SRC_UTILS_REFERENCE_INFO_H_
+
+#include <array>
+#include <cstdint>
+
+#include "src/utils/array_2d.h"
+#include "src/utils/constants.h"
+#include "src/utils/types.h"
+
+namespace libgav1 {
+
+// This struct collects some members related to reference frames in one place to
+// make it easier to pass them as parameters to some dsp functions.
+struct ReferenceInfo {
+  // Initialize |motion_field_reference_frame| so that
+  // Tile::StoreMotionFieldMvsIntoCurrentFrame() can skip some updates when
+  // the updates are the same as the initialized value.
+  // Set to kReferenceFrameIntra instead of kReferenceFrameNone to simplify
+  // branch conditions in motion field projection.
+  // The following memory initialization of contiguous memory is very fast. It
+  // is not recommended to make the initialization multi-threaded, unless the
+  // memory which needs to be initialized in each thread is still contiguous.
+  LIBGAV1_MUST_USE_RESULT bool Reset(int rows, int columns) {
+    return motion_field_reference_frame.Reset(rows, columns,
+                                              /*zero_initialize=*/true) &&
+           motion_field_mv.Reset(
+               rows, columns,
+#if LIBGAV1_MSAN
+               // It is set in Tile::StoreMotionFieldMvsIntoCurrentFrame() only
+               // for qualified blocks. In MotionFieldProjectionKernel() dsp
+               // optimizations, it is read no matter it was set or not.
+               /*zero_initialize=*/true
+#else
+               /*zero_initialize=*/false
+#endif
+           );
+  }
+
+  // All members are used by inter frames only.
+  // For intra frames, they are not initialized.
+
+  std::array<uint8_t, kNumReferenceFrameTypes> order_hint;
+
+  // An example when |relative_distance_from| does not equal
+  // -|relative_distance_to|:
+  // |relative_distance_from| = GetRelativeDistance(7, 71, 25) = -64
+  // -|relative_distance_to| = -GetRelativeDistance(71, 7, 25) = 64
+  // This is why we need both |relative_distance_from| and
+  // |relative_distance_to|.
+  // |relative_distance_from|: Relative distances from reference frames to this
+  // frame.
+  std::array<int8_t, kNumReferenceFrameTypes> relative_distance_from;
+  // |relative_distance_to|: Relative distances to reference frames.
+  std::array<int8_t, kNumReferenceFrameTypes> relative_distance_to;
+
+  // Skip motion field projection of specific types of frames if their
+  // |relative_distance_to| is negative or too large.
+  std::array<bool, kNumReferenceFrameTypes> skip_references;
+  // Lookup table to get motion field projection division multiplier of specific
+  // types of frames. Derived from kProjectionMvDivisionLookup.
+  std::array<int16_t, kNumReferenceFrameTypes> projection_divisions;
+
+  // The current frame's |motion_field_reference_frame| and |motion_field_mv_|
+  // are guaranteed to be allocated only when refresh_frame_flags is not 0.
+  // Array of size (rows4x4 / 2) x (columns4x4 / 2). Entry at i, j corresponds
+  // to MfRefFrames[i * 2 + 1][j * 2 + 1] in the spec.
+  Array2D<ReferenceFrameType> motion_field_reference_frame;
+  // Array of size (rows4x4 / 2) x (columns4x4 / 2). Entry at i, j corresponds
+  // to MfMvs[i * 2 + 1][j * 2 + 1] in the spec.
+  Array2D<MotionVector> motion_field_mv;
+};
+
+}  // namespace libgav1
+
+#endif  // LIBGAV1_SRC_UTILS_REFERENCE_INFO_H_