1 files changed, 67 insertions, 0 deletions
diff --git a/third_party/aom/av1/encoder/sparse_linear_solver.h b/third_party/aom/av1/encoder/sparse_linear_solver.h
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+++ b/third_party/aom/av1/encoder/sparse_linear_solver.h
@@ -0,0 +1,67 @@
+/*
+ * Copyright (c) 2021, Alliance for Open Media. All rights reserved
+ *
+ * This source code is subject to the terms of the BSD 2 Clause License and
+ * the Alliance for Open Media Patent License 1.0. If the BSD 2 Clause License
+ * was not distributed with this source code in the LICENSE file, you can
+ * obtain it at www.aomedia.org/license/software. If the Alliance for Open
+ * Media Patent License 1.0 was not distributed with this source code in the
+ * PATENTS file, you can obtain it at www.aomedia.org/license/patent.
+ */
+
+#ifndef AOM_AV1_ENCODER_SPARSE_LINEAR_SOLVER_H_
+#define AOM_AV1_ENCODER_SPARSE_LINEAR_SOLVER_H_
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+#include "config/aom_config.h"
+
+#if CONFIG_OPTICAL_FLOW_API
+
+// Number of iterations for solving linear equations.
+#define MAX_CG_SP_ITER 100
+
+typedef struct {
+  int n_elem;  // number of non-zero elements
+  int n_rows;
+  int n_cols;
+  // using arrays to represent non-zero elements.
+  int *col_pos;
+  int *row_pos;  // starts with 0
+  double *value;
+} SPARSE_MTX;
+
+int av1_init_sparse_mtx(const int *rows, const int *cols, const double *values,
+                        int num_elem, int num_rows, int num_cols,
+                        SPARSE_MTX *sm);
+int av1_init_combine_sparse_mtx(const SPARSE_MTX *sm1, const SPARSE_MTX *sm2,
+                                SPARSE_MTX *sm, int row_offset1,
+                                int col_offset1, int row_offset2,
+                                int col_offset2, int new_n_rows,
+                                int new_n_cols);
+void av1_free_sparse_mtx_elems(SPARSE_MTX *sm);
+
+void av1_mtx_vect_multi_right(const SPARSE_MTX *sm, const double *srcv,
+                              double *dstv, int dstl);
+void av1_mtx_vect_multi_left(const SPARSE_MTX *sm, const double *srcv,
+                             double *dstv, int dstl);
+double av1_vect_vect_multi(const double *src1, int src1l, const double *src2);
+void av1_constant_multiply_sparse_matrix(SPARSE_MTX *sm, double c);
+
+int av1_conjugate_gradient_sparse(const SPARSE_MTX *A, const double *b, int bl,
+                                  double *x);
+int av1_bi_conjugate_gradient_sparse(const SPARSE_MTX *A, const double *b,
+                                     int bl, double *x);
+int av1_jacobi_sparse(const SPARSE_MTX *A, const double *b, int bl, double *x);
+int av1_steepest_descent_sparse(const SPARSE_MTX *A, const double *b, int bl,
+                                double *x);
+
+#endif  // CONFIG_OPTICAL_FLOW_API
+
+#ifdef __cplusplus
+}  // extern "C"
+#endif
+
+#endif /* AOM_AV1_ENCODER_SPARSE_LINEAR_SOLVER_H_ */