1/*
2 *  Copyright (c) 2010 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
12#ifndef VP8_COMMON_ENTROPYMV_H_
13#define VP8_COMMON_ENTROPYMV_H_
14
15#include "treecoder.h"
16
17#ifdef __cplusplus
18extern "C" {
19#endif
20
21enum
22{
23    mv_max  = 1023,              /* max absolute value of a MV component */
24    MVvals = (2 * mv_max) + 1,   /* # possible values "" */
25    mvfp_max  = 255,              /* max absolute value of a full pixel MV component */
26    MVfpvals = (2 * mvfp_max) +1, /* # possible full pixel MV values */
27
28    mvlong_width = 10,       /* Large MVs have 9 bit magnitudes */
29    mvnum_short = 8,         /* magnitudes 0 through 7 */
30
31    /* probability offsets for coding each MV component */
32
33    mvpis_short = 0,         /* short (<= 7) vs long (>= 8) */
34    MVPsign,                /* sign for non-zero */
35    MVPshort,               /* 8 short values = 7-position tree */
36
37    MVPbits = MVPshort + mvnum_short - 1, /* mvlong_width long value bits */
38    MVPcount = MVPbits + mvlong_width    /* (with independent probabilities) */
39};
40
41typedef struct mv_context
42{
43    vp8_prob prob[MVPcount];  /* often come in row, col pairs */
44} MV_CONTEXT;
45
46extern const MV_CONTEXT vp8_mv_update_probs[2], vp8_default_mv_context[2];
47
48#ifdef __cplusplus
49}  // extern "C"
50#endif
51
52#endif  // VP8_COMMON_ENTROPYMV_H_
53