2 * Copyright (c) 2010 The WebM project authors. All Rights Reserved.
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.
12 #include "findnearmv.h"
14 const unsigned char vp8_mbsplit_offset[4][16] = {
15 { 0, 8, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0},
16 { 0, 2, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0},
17 { 0, 2, 8, 10, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0},
18 { 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15}
21 /* Predict motion vectors using those from already-decoded nearby blocks.
22 Note that we only consider one 4x4 subblock from each candidate 16x16
24 void vp8_find_near_mvs
27 const MODE_INFO *here,
33 int *ref_frame_sign_bias
36 const MODE_INFO *above = here - xd->mode_info_stride;
37 const MODE_INFO *left = here - 1;
38 const MODE_INFO *aboveleft = above - 1;
40 int_mv *mv = near_mvs;
42 enum {CNT_INTRA, CNT_NEAREST, CNT_NEAR, CNT_SPLITMV};
44 /* Zero accumulators */
45 mv[0].as_int = mv[1].as_int = mv[2].as_int = 0;
46 cnt[0] = cnt[1] = cnt[2] = cnt[3] = 0;
49 if (above->mbmi.ref_frame != INTRA_FRAME)
51 if (above->mbmi.mv.as_int)
53 (++mv)->as_int = above->mbmi.mv.as_int;
54 mv_bias(ref_frame_sign_bias[above->mbmi.ref_frame], refframe, mv, ref_frame_sign_bias);
62 if (left->mbmi.ref_frame != INTRA_FRAME)
64 if (left->mbmi.mv.as_int)
68 this_mv.as_int = left->mbmi.mv.as_int;
69 mv_bias(ref_frame_sign_bias[left->mbmi.ref_frame], refframe, &this_mv, ref_frame_sign_bias);
71 if (this_mv.as_int != mv->as_int)
73 (++mv)->as_int = this_mv.as_int;
83 /* Process above left */
84 if (aboveleft->mbmi.ref_frame != INTRA_FRAME)
86 if (aboveleft->mbmi.mv.as_int)
90 this_mv.as_int = aboveleft->mbmi.mv.as_int;
91 mv_bias(ref_frame_sign_bias[aboveleft->mbmi.ref_frame], refframe, &this_mv, ref_frame_sign_bias);
93 if (this_mv.as_int != mv->as_int)
95 (++mv)->as_int = this_mv.as_int;
105 /* If we have three distinct MV's ... */
106 if (cnt[CNT_SPLITMV])
108 /* See if above-left MV can be merged with NEAREST */
109 if (mv->as_int == near_mvs[CNT_NEAREST].as_int)
110 cnt[CNT_NEAREST] += 1;
113 cnt[CNT_SPLITMV] = ((above->mbmi.mode == SPLITMV)
114 + (left->mbmi.mode == SPLITMV)) * 2
115 + (aboveleft->mbmi.mode == SPLITMV);
117 /* Swap near and nearest if necessary */
118 if (cnt[CNT_NEAR] > cnt[CNT_NEAREST])
121 tmp = cnt[CNT_NEAREST];
122 cnt[CNT_NEAREST] = cnt[CNT_NEAR];
124 tmp = near_mvs[CNT_NEAREST].as_int;
125 near_mvs[CNT_NEAREST].as_int = near_mvs[CNT_NEAR].as_int;
126 near_mvs[CNT_NEAR].as_int = tmp;
129 /* Use near_mvs[0] to store the "best" MV */
130 if (cnt[CNT_NEAREST] >= cnt[CNT_INTRA])
131 near_mvs[CNT_INTRA] = near_mvs[CNT_NEAREST];
133 /* Set up return values */
134 best_mv->as_int = near_mvs[0].as_int;
135 nearest->as_int = near_mvs[CNT_NEAREST].as_int;
136 nearby->as_int = near_mvs[CNT_NEAR].as_int;
138 //TODO: move clamp outside findnearmv
139 vp8_clamp_mv2(nearest, xd);
140 vp8_clamp_mv2(nearby, xd);
141 vp8_clamp_mv2(best_mv, xd);
144 vp8_prob *vp8_mv_ref_probs(
145 vp8_prob p[VP8_MVREFS-1], const int near_mv_ref_ct[4]
148 p[0] = vp8_mode_contexts [near_mv_ref_ct[0]] [0];
149 p[1] = vp8_mode_contexts [near_mv_ref_ct[1]] [1];
150 p[2] = vp8_mode_contexts [near_mv_ref_ct[2]] [2];
151 p[3] = vp8_mode_contexts [near_mv_ref_ct[3]] [3];
152 /*p[3] = vp8_mode_contexts [near_mv_ref_ct[1] + near_mv_ref_ct[2] + near_mv_ref_ct[3]] [3];*/