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