ref: d90b1ee16cb13f3b868efc5b084b33a65000689e
dir: /vp8/common/entropymv.h/
/*
* Copyright (c) 2010 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 __INC_ENTROPYMV_H
#define __INC_ENTROPYMV_H
#include "treecoder.h"
#include "vpx_config.h"
#if CONFIG_HIGH_PRECISION_MV
#define MV_SHIFT 0
#else
#define MV_SHIFT 1
#endif
enum
{
#if CONFIG_HIGH_PRECISION_MV
mv_max = 2047, /* max absolute value of a MV component */
MVvals = (2 * mv_max) + 1, /* # possible values "" */
mvlong_width = 11, /* Large MVs have 9 bit magnitudes */
mvnum_short = 16, /* magnitudes 0 through 15 */
mvnum_short_bits = 4, /* number of bits for short mvs */
#else
mv_max = 1023, /* max absolute value of a MV component */
MVvals = (2 * mv_max) + 1, /* # possible values "" */
mvlong_width = 10, /* Large MVs have 9 bit magnitudes */
mvnum_short = 8, /* magnitudes 0 through 7 */
mvnum_short_bits = 3, /* number of bits for short mvs */
#endif
mvfp_max = 255, /* max absolute value of a full pixel MV component */
MVfpvals = (2 * mvfp_max) + 1, /* # possible full pixel MV values */
/* probability offsets for coding each MV component */
mvpis_short = 0, /* short (<= 7) vs long (>= 8) */
MVPsign, /* sign for non-zero */
MVPshort, /* 8 short values = 7-position tree */
MVPbits = MVPshort + mvnum_short - 1, /* mvlong_width long value bits */
MVPcount = MVPbits + mvlong_width /* (with independent probabilities) */
};
typedef struct mv_context
{
vp8_prob prob[MVPcount]; /* often come in row, col pairs */
} MV_CONTEXT;
extern const MV_CONTEXT vp8_mv_update_probs[2], vp8_default_mv_context[2];
#endif