| /* |
| * 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_ |