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 #include "findnearmv.h" 13 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} 19 }; 20 21 /* Predict motion vectors using those from already-decoded nearby blocks. 22 Note that we only consider one 4x4 subblock from each candidate 16x16 23 macroblock. */ 24 void vp8_find_near_mvs 25 ( 26 MACROBLOCKD *xd, 27 const MODE_INFO *here, 28 MV *nearest, 29 MV *nearby, 30 MV *best_mv, 31 int cnt[4], 32 int refframe, 33 int *ref_frame_sign_bias 34 ) 35 { 36 const MODE_INFO *above = here - xd->mode_info_stride; 37 const MODE_INFO *left = here - 1; 38 const MODE_INFO *aboveleft = above - 1; 39 int_mv near_mvs[4]; 40 int_mv *mv = near_mvs; 41 int *cntx = cnt; 42 enum {CNT_INTRA, CNT_NEAREST, CNT_NEAR, CNT_SPLITMV}; 43 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; 47 48 /* Process above */ 49 if (above->mbmi.ref_frame != INTRA_FRAME) 50 { 51 if (above->mbmi.mv.as_int) 52 { 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); 55 ++cntx; 56 } 57 58 *cntx += 2; 59 } 60 61 /* Process left */ 62 if (left->mbmi.ref_frame != INTRA_FRAME) 63 { 64 if (left->mbmi.mv.as_int) 65 { 66 int_mv this_mv; 67 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); 70 71 if (this_mv.as_int != mv->as_int) 72 { 73 (++mv)->as_int = this_mv.as_int; 74 ++cntx; 75 } 76 77 *cntx += 2; 78 } 79 else 80 cnt[CNT_INTRA] += 2; 81 } 82 83 /* Process above left */ 84 if (aboveleft->mbmi.ref_frame != INTRA_FRAME) 85 { 86 if (aboveleft->mbmi.mv.as_int) 87 { 88 int_mv this_mv; 89 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); 92 93 if (this_mv.as_int != mv->as_int) 94 { 95 (++mv)->as_int = this_mv.as_int; 96 ++cntx; 97 } 98 99 *cntx += 1; 100 } 101 else 102 cnt[CNT_INTRA] += 1; 103 } 104 105 /* If we have three distinct MV's ... */ 106 if (cnt[CNT_SPLITMV]) 107 { 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; 111 } 112 113 cnt[CNT_SPLITMV] = ((above->mbmi.mode == SPLITMV) 114 + (left->mbmi.mode == SPLITMV)) * 2 115 + (aboveleft->mbmi.mode == SPLITMV); 116 117 /* Swap near and nearest if necessary */ 118 if (cnt[CNT_NEAR] > cnt[CNT_NEAREST]) 119 { 120 int tmp; 121 tmp = cnt[CNT_NEAREST]; 122 cnt[CNT_NEAREST] = cnt[CNT_NEAR]; 123 cnt[CNT_NEAR] = tmp; 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; 127 } 128 129 /* 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]; 132 133 /* Set up return values */ 134 *best_mv = near_mvs[0].as_mv; 135 *nearest = near_mvs[CNT_NEAREST].as_mv; 136 *nearby = near_mvs[CNT_NEAR].as_mv; 137 138 vp8_clamp_mv(nearest, xd); 139 vp8_clamp_mv(nearby, xd); 140 vp8_clamp_mv(best_mv, xd); /*TODO: move this up before the copy*/ 141 } 142 143 vp8_prob *vp8_mv_ref_probs( 144 vp8_prob p[VP8_MVREFS-1], const int near_mv_ref_ct[4] 145 ) 146 { 147 p[0] = vp8_mode_contexts [near_mv_ref_ct[0]] [0]; 148 p[1] = vp8_mode_contexts [near_mv_ref_ct[1]] [1]; 149 p[2] = vp8_mode_contexts [near_mv_ref_ct[2]] [2]; 150 p[3] = vp8_mode_contexts [near_mv_ref_ct[3]] [3]; 151 /*p[3] = vp8_mode_contexts [near_mv_ref_ct[1] + near_mv_ref_ct[2] + near_mv_ref_ct[3]] [3];*/ 152 return p; 153 } 154 155 const B_MODE_INFO *vp8_left_bmi(const MODE_INFO *cur_mb, int b) 156 { 157 if (!(b & 3)) 158 { 159 /* On L edge, get from MB to left of us */ 160 --cur_mb; 161 b += 4; 162 } 163 164 return cur_mb->bmi + b - 1; 165 } 166 167 const B_MODE_INFO *vp8_above_bmi(const MODE_INFO *cur_mb, int b, int mi_stride) 168 { 169 if (!(b >> 2)) 170 { 171 /* On top edge, get from MB above us */ 172 cur_mb -= mi_stride; 173 b += 16; 174 } 175 176 return cur_mb->bmi + b - 4; 177 } 178