1/*
2 *  Copyright (c) 2011 The WebM project authors. All Rights Reserved.
3 *
4 *  Use of this source code is governed by a BSD-style license
5 *  that can be found in the LICENSE file in the root of the source
6 *  tree. An additional intellectual property rights grant can be found
7 *  in the file PATENTS.  All contributing project authors may
8 *  be found in the AUTHORS file in the root of the source tree.
9 */
10
11#ifndef VP9_COMMON_VP9_FILTER_H_
12#define VP9_COMMON_VP9_FILTER_H_
13
14#include "./vpx_config.h"
15#include "vpx/vpx_integer.h"
16#include "vpx_ports/mem.h"
17
18
19#ifdef __cplusplus
20extern "C" {
21#endif
22
23#define FILTER_BITS 7
24
25#define SUBPEL_BITS 4
26#define SUBPEL_MASK ((1 << SUBPEL_BITS) - 1)
27#define SUBPEL_SHIFTS (1 << SUBPEL_BITS)
28#define SUBPEL_TAPS 8
29
30typedef enum {
31  EIGHTTAP = 0,
32  EIGHTTAP_SMOOTH = 1,
33  EIGHTTAP_SHARP = 2,
34  BILINEAR = 3,
35  SWITCHABLE = 4  /* should be the last one */
36} INTERP_FILTER;
37
38typedef int16_t InterpKernel[SUBPEL_TAPS];
39
40const InterpKernel *vp9_get_interp_kernel(INTERP_FILTER filter);
41
42DECLARE_ALIGNED(256, extern const InterpKernel,
43                vp9_bilinear_filters[SUBPEL_SHIFTS]);
44DECLARE_ALIGNED(256, extern const InterpKernel,
45                vp9_sub_pel_filters_8[SUBPEL_SHIFTS]);
46DECLARE_ALIGNED(256, extern const InterpKernel,
47                vp9_sub_pel_filters_8s[SUBPEL_SHIFTS]);
48DECLARE_ALIGNED(256, extern const InterpKernel,
49                vp9_sub_pel_filters_8lp[SUBPEL_SHIFTS]);
50
51// The VP9_BILINEAR_FILTERS_2TAP macro returns a pointer to the bilinear
52// filter kernel as a 2 tap filter.
53#define BILINEAR_FILTERS_2TAP(x) \
54  (vp9_bilinear_filters[(x)] + SUBPEL_TAPS/2 - 1)
55
56#ifdef __cplusplus
57}  // extern "C"
58#endif
59
60#endif  // VP9_COMMON_VP9_FILTER_H_
61