2 * H.26L/H.264/AVC/JVT/14496-10/... motion vector predicion
3 * Copyright (c) 2003 Michael Niedermayer <michaelni@gmx.at>
5 * This file is part of FFmpeg.
7 * FFmpeg is free software; you can redistribute it and/or
8 * modify it under the terms of the GNU Lesser General Public
9 * License as published by the Free Software Foundation; either
10 * version 2.1 of the License, or (at your option) any later version.
12 * FFmpeg is distributed in the hope that it will be useful,
13 * but WITHOUT ANY WARRANTY; without even the implied warranty of
14 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
15 * Lesser General Public License for more details.
17 * You should have received a copy of the GNU Lesser General Public
18 * License along with FFmpeg; if not, write to the Free Software
19 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
23 * @file libavcodec/h264_mvpred.h
24 * H.264 / AVC / MPEG4 part10 motion vector predicion.
25 * @author Michael Niedermayer <michaelni@gmx.at>
28 #ifndef AVCODEC_H264_MVPRED_H
29 #define AVCODEC_H264_MVPRED_H
38 static inline int fetch_diagonal_mv(H264Context *h, const int16_t **C, int i, int list, int part_width){
39 const int topright_ref= h->ref_cache[list][ i - 8 + part_width ];
40 MpegEncContext *s = &h->s;
42 /* there is no consistent mapping of mvs to neighboring locations that will
43 * make mbaff happy, so we can't move all this logic to fill_caches */
46 #define SET_DIAG_MV(MV_OP, REF_OP, X4, Y4)\
47 const int x4 = X4, y4 = Y4;\
48 const int mb_type = mb_types[(x4>>2)+(y4>>2)*s->mb_stride];\
49 if(!USES_LIST(mb_type,list))\
50 return LIST_NOT_USED;\
51 mv = s->current_picture_ptr->motion_val[list][x4 + y4*h->b_stride];\
52 h->mv_cache[list][scan8[0]-2][0] = mv[0];\
53 h->mv_cache[list][scan8[0]-2][1] = mv[1] MV_OP;\
54 return s->current_picture_ptr->ref_index[list][(x4>>1) + (y4>>1)*h->b8_stride] REF_OP;
56 if(topright_ref == PART_NOT_AVAILABLE
57 && i >= scan8[0]+8 && (i&7)==4
58 && h->ref_cache[list][scan8[0]-1] != PART_NOT_AVAILABLE){
59 const uint32_t *mb_types = s->current_picture_ptr->mb_type;
61 *(uint32_t*)h->mv_cache[list][scan8[0]-2] = 0;
62 *C = h->mv_cache[list][scan8[0]-2];
65 && IS_INTERLACED(mb_types[h->left_mb_xy[0]])){
66 SET_DIAG_MV(*2, >>1, s->mb_x*4-1, (s->mb_y|1)*4+(s->mb_y&1)*2+(i>>4)-1);
69 && !IS_INTERLACED(mb_types[h->left_mb_xy[0]])){
70 // left shift will turn LIST_NOT_USED into PART_NOT_AVAILABLE, but that's OK.
71 SET_DIAG_MV(/2, <<1, s->mb_x*4-1, (s->mb_y&~1)*4 - 1 + ((i-scan8[0])>>3)*2);
77 if(topright_ref != PART_NOT_AVAILABLE){
78 *C= h->mv_cache[list][ i - 8 + part_width ];
81 tprintf(s->avctx, "topright MV not available\n");
83 *C= h->mv_cache[list][ i - 8 - 1 ];
84 return h->ref_cache[list][ i - 8 - 1 ];
89 * gets the predicted MV.
90 * @param n the block index
91 * @param part_width the width of the partition (4, 8,16) -> (1, 2, 4)
92 * @param mx the x component of the predicted motion vector
93 * @param my the y component of the predicted motion vector
95 static inline void pred_motion(H264Context * const h, int n, int part_width, int list, int ref, int * const mx, int * const my){
96 const int index8= scan8[n];
97 const int top_ref= h->ref_cache[list][ index8 - 8 ];
98 const int left_ref= h->ref_cache[list][ index8 - 1 ];
99 const int16_t * const A= h->mv_cache[list][ index8 - 1 ];
100 const int16_t * const B= h->mv_cache[list][ index8 - 8 ];
102 int diagonal_ref, match_count;
104 assert(part_width==1 || part_width==2 || part_width==4);
114 diagonal_ref= fetch_diagonal_mv(h, &C, index8, list, part_width);
115 match_count= (diagonal_ref==ref) + (top_ref==ref) + (left_ref==ref);
116 tprintf(h->s.avctx, "pred_motion match_count=%d\n", match_count);
117 if(match_count > 1){ //most common
118 *mx= mid_pred(A[0], B[0], C[0]);
119 *my= mid_pred(A[1], B[1], C[1]);
120 }else if(match_count==1){
124 }else if(top_ref==ref){
132 if(top_ref == PART_NOT_AVAILABLE && diagonal_ref == PART_NOT_AVAILABLE && left_ref != PART_NOT_AVAILABLE){
136 *mx= mid_pred(A[0], B[0], C[0]);
137 *my= mid_pred(A[1], B[1], C[1]);
141 tprintf(h->s.avctx, "pred_motion (%2d %2d %2d) (%2d %2d %2d) (%2d %2d %2d) -> (%2d %2d %2d) at %2d %2d %d list %d\n", top_ref, B[0], B[1], diagonal_ref, C[0], C[1], left_ref, A[0], A[1], ref, *mx, *my, h->s.mb_x, h->s.mb_y, n, list);
145 * gets the directionally predicted 16x8 MV.
146 * @param n the block index
147 * @param mx the x component of the predicted motion vector
148 * @param my the y component of the predicted motion vector
150 static inline void pred_16x8_motion(H264Context * const h, int n, int list, int ref, int * const mx, int * const my){
152 const int top_ref= h->ref_cache[list][ scan8[0] - 8 ];
153 const int16_t * const B= h->mv_cache[list][ scan8[0] - 8 ];
155 tprintf(h->s.avctx, "pred_16x8: (%2d %2d %2d) at %2d %2d %d list %d\n", top_ref, B[0], B[1], h->s.mb_x, h->s.mb_y, n, list);
163 const int left_ref= h->ref_cache[list][ scan8[8] - 1 ];
164 const int16_t * const A= h->mv_cache[list][ scan8[8] - 1 ];
166 tprintf(h->s.avctx, "pred_16x8: (%2d %2d %2d) at %2d %2d %d list %d\n", left_ref, A[0], A[1], h->s.mb_x, h->s.mb_y, n, list);
176 pred_motion(h, n, 4, list, ref, mx, my);
180 * gets the directionally predicted 8x16 MV.
181 * @param n the block index
182 * @param mx the x component of the predicted motion vector
183 * @param my the y component of the predicted motion vector
185 static inline void pred_8x16_motion(H264Context * const h, int n, int list, int ref, int * const mx, int * const my){
187 const int left_ref= h->ref_cache[list][ scan8[0] - 1 ];
188 const int16_t * const A= h->mv_cache[list][ scan8[0] - 1 ];
190 tprintf(h->s.avctx, "pred_8x16: (%2d %2d %2d) at %2d %2d %d list %d\n", left_ref, A[0], A[1], h->s.mb_x, h->s.mb_y, n, list);
201 diagonal_ref= fetch_diagonal_mv(h, &C, scan8[4], list, 2);
203 tprintf(h->s.avctx, "pred_8x16: (%2d %2d %2d) at %2d %2d %d list %d\n", diagonal_ref, C[0], C[1], h->s.mb_x, h->s.mb_y, n, list);
205 if(diagonal_ref == ref){
213 pred_motion(h, n, 2, list, ref, mx, my);
216 static inline void pred_pskip_motion(H264Context * const h, int * const mx, int * const my){
217 const int top_ref = h->ref_cache[0][ scan8[0] - 8 ];
218 const int left_ref= h->ref_cache[0][ scan8[0] - 1 ];
220 tprintf(h->s.avctx, "pred_pskip: (%d) (%d) at %2d %2d\n", top_ref, left_ref, h->s.mb_x, h->s.mb_y);
222 if(top_ref == PART_NOT_AVAILABLE || left_ref == PART_NOT_AVAILABLE
223 || !( top_ref | *(uint32_t*)h->mv_cache[0][ scan8[0] - 8 ])
224 || !(left_ref | *(uint32_t*)h->mv_cache[0][ scan8[0] - 1 ])){
230 pred_motion(h, 0, 4, 0, 0, mx, my);
235 #endif /* AVCODEC_H264_MVPRED_H */