ref: d166be653e76d5ed4fc7a5c1e41abd22ebfd824f
dir: /vp9/common/vp9_filter.h/
/*
* Copyright (c) 2011 The WebM project authors. All Rights Reserved.
*
* Use of this source code is governed by a BSD-style license
* that can be found in the LICENSE file in the root of the source
* tree. An additional intellectual property rights grant can be found
* in the file PATENTS. All contributing project authors may
* be found in the AUTHORS file in the root of the source tree.
*/
#ifndef VP9_COMMON_VP9_FILTER_H_
#define VP9_COMMON_VP9_FILTER_H_
#include "./vpx_config.h"
#include "vpx/vpx_integer.h"
#include "vpx_ports/mem.h"
#ifdef __cplusplus
extern "C" {
#endif
#define FILTER_BITS 7
#define SUBPEL_BITS 4
#define SUBPEL_MASK ((1 << SUBPEL_BITS) - 1)
#define SUBPEL_SHIFTS (1 << SUBPEL_BITS)
#define SUBPEL_TAPS 8
typedef enum {
EIGHTTAP = 0,
EIGHTTAP_SMOOTH = 1,
EIGHTTAP_SHARP = 2,
BILINEAR = 3,
SWITCHABLE = 4 /* should be the last one */
} INTERP_FILTER;
// Number of switchable filters
#define SWITCHABLE_FILTERS 3
// The codec can operate in four possible inter prediction filter mode:
// 8-tap, 8-tap-smooth, 8-tap-sharp, and switching between the three.
#define SWITCHABLE_FILTER_CONTEXTS (SWITCHABLE_FILTERS + 1)
typedef int16_t InterpKernel[SUBPEL_TAPS];
const InterpKernel *vp9_get_interp_kernel(INTERP_FILTER filter);
DECLARE_ALIGNED(256, extern const InterpKernel,
vp9_bilinear_filters[SUBPEL_SHIFTS]);
// The VP9_BILINEAR_FILTERS_2TAP macro returns a pointer to the bilinear
// filter kernel as a 2 tap filter.
#define BILINEAR_FILTERS_2TAP(x) \
(vp9_bilinear_filters[(x)] + SUBPEL_TAPS/2 - 1)
#ifdef __cplusplus
} // extern "C"
#endif
#endif // VP9_COMMON_VP9_FILTER_H_