Import aom library

This is the reference implementation for the Alliance for Open Media's av1 video code.

The commit used was 4d668d7feb1f8abd809d1bca0418570a7f142a36.

third_party/aom/av1/common/cdef.h

@@ -0,0 +1,53 @@
+/*
+ * Copyright (c) 2016, 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 AV1_COMMON_DERING_H_
+#define AV1_COMMON_DERING_H_
+
+#define CDEF_STRENGTH_BITS 7
+
+#define DERING_STRENGTHS 32
+#define CLPF_STRENGTHS 4
+
+#include "./aom_config.h"
+#include "aom/aom_integer.h"
+#include "aom_ports/mem.h"
+#include "av1/common/od_dering.h"
+#include "av1/common/onyxc_int.h"
+#include "./od_dering.h"
+
+static INLINE int sign(int i) { return i < 0 ? -1 : 1; }
+
+static INLINE int constrain(int diff, int threshold, unsigned int damping) {
+  return threshold
+             ? sign(diff) *
+                   AOMMIN(
+                       abs(diff),
+                       AOMMAX(0, threshold - (abs(diff) >>
+                                              (damping - get_msb(threshold)))))
+             : 0;
+}
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+int sb_all_skip(const AV1_COMMON *const cm, int mi_row, int mi_col);
+int sb_compute_dering_list(const AV1_COMMON *const cm, int mi_row, int mi_col,
+                           dering_list *dlist, int filter_skip);
+void av1_cdef_frame(YV12_BUFFER_CONFIG *frame, AV1_COMMON *cm, MACROBLOCKD *xd);
+
+void av1_cdef_search(YV12_BUFFER_CONFIG *frame, const YV12_BUFFER_CONFIG *ref,
+                     AV1_COMMON *cm, MACROBLOCKD *xd);
+
+#ifdef __cplusplus
+}  // extern "C"
+#endif
+#endif  // AV1_COMMON_DERING_H_