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 #include <math.h>
12 
13 #include "vp9/common/vp9_common.h"
14 #include "vp9/common/vp9_entropymode.h"
15 
16 #include "vp9/encoder/vp9_cost.h"
17 #include "vp9/encoder/vp9_encodemv.h"
18 
19 #include "vpx_dsp/vpx_dsp_common.h"
20 
21 static struct vp9_token mv_joint_encodings[MV_JOINTS];
22 static struct vp9_token mv_class_encodings[MV_CLASSES];
23 static struct vp9_token mv_fp_encodings[MV_FP_SIZE];
24 static struct vp9_token mv_class0_encodings[CLASS0_SIZE];
25 
vp9_entropy_mv_init(void)26 void vp9_entropy_mv_init(void) {
27   vp9_tokens_from_tree(mv_joint_encodings, vp9_mv_joint_tree);
28   vp9_tokens_from_tree(mv_class_encodings, vp9_mv_class_tree);
29   vp9_tokens_from_tree(mv_class0_encodings, vp9_mv_class0_tree);
30   vp9_tokens_from_tree(mv_fp_encodings, vp9_mv_fp_tree);
31 }
32 
encode_mv_component(vpx_writer * w,int comp,const nmv_component * mvcomp,int usehp)33 static void encode_mv_component(vpx_writer* w, int comp,
34                                 const nmv_component* mvcomp, int usehp) {
35   int offset;
36   const int sign = comp < 0;
37   const int mag = sign ? -comp : comp;
38   const int mv_class = vp9_get_mv_class(mag - 1, &offset);
39   const int d = offset >> 3;                // int mv data
40   const int fr = (offset >> 1) & 3;         // fractional mv data
41   const int hp = offset & 1;                // high precision mv data
42 
43   assert(comp != 0);
44 
45   // Sign
46   vpx_write(w, sign, mvcomp->sign);
47 
48   // Class
49   vp9_write_token(w, vp9_mv_class_tree, mvcomp->classes,
50                   &mv_class_encodings[mv_class]);
51 
52   // Integer bits
53   if (mv_class == MV_CLASS_0) {
54     vp9_write_token(w, vp9_mv_class0_tree, mvcomp->class0,
55                     &mv_class0_encodings[d]);
56   } else {
57     int i;
58     const int n = mv_class + CLASS0_BITS - 1;  // number of bits
59     for (i = 0; i < n; ++i)
60       vpx_write(w, (d >> i) & 1, mvcomp->bits[i]);
61   }
62 
63   // Fractional bits
64   vp9_write_token(w, vp9_mv_fp_tree,
65                   mv_class == MV_CLASS_0 ?  mvcomp->class0_fp[d] : mvcomp->fp,
66                   &mv_fp_encodings[fr]);
67 
68   // High precision bit
69   if (usehp)
70     vpx_write(w, hp,
71               mv_class == MV_CLASS_0 ? mvcomp->class0_hp : mvcomp->hp);
72 }
73 
74 
build_nmv_component_cost_table(int * mvcost,const nmv_component * const mvcomp,int usehp)75 static void build_nmv_component_cost_table(int *mvcost,
76                                            const nmv_component* const mvcomp,
77                                            int usehp) {
78   int i, v;
79   int sign_cost[2], class_cost[MV_CLASSES], class0_cost[CLASS0_SIZE];
80   int bits_cost[MV_OFFSET_BITS][2];
81   int class0_fp_cost[CLASS0_SIZE][MV_FP_SIZE], fp_cost[MV_FP_SIZE];
82   int class0_hp_cost[2], hp_cost[2];
83 
84   sign_cost[0] = vp9_cost_zero(mvcomp->sign);
85   sign_cost[1] = vp9_cost_one(mvcomp->sign);
86   vp9_cost_tokens(class_cost, mvcomp->classes, vp9_mv_class_tree);
87   vp9_cost_tokens(class0_cost, mvcomp->class0, vp9_mv_class0_tree);
88   for (i = 0; i < MV_OFFSET_BITS; ++i) {
89     bits_cost[i][0] = vp9_cost_zero(mvcomp->bits[i]);
90     bits_cost[i][1] = vp9_cost_one(mvcomp->bits[i]);
91   }
92 
93   for (i = 0; i < CLASS0_SIZE; ++i)
94     vp9_cost_tokens(class0_fp_cost[i], mvcomp->class0_fp[i], vp9_mv_fp_tree);
95   vp9_cost_tokens(fp_cost, mvcomp->fp, vp9_mv_fp_tree);
96 
97   if (usehp) {
98     class0_hp_cost[0] = vp9_cost_zero(mvcomp->class0_hp);
99     class0_hp_cost[1] = vp9_cost_one(mvcomp->class0_hp);
100     hp_cost[0] = vp9_cost_zero(mvcomp->hp);
101     hp_cost[1] = vp9_cost_one(mvcomp->hp);
102   }
103   mvcost[0] = 0;
104   for (v = 1; v <= MV_MAX; ++v) {
105     int z, c, o, d, e, f, cost = 0;
106     z = v - 1;
107     c = vp9_get_mv_class(z, &o);
108     cost += class_cost[c];
109     d = (o >> 3);               /* int mv data */
110     f = (o >> 1) & 3;           /* fractional pel mv data */
111     e = (o & 1);                /* high precision mv data */
112     if (c == MV_CLASS_0) {
113       cost += class0_cost[d];
114     } else {
115       int i, b;
116       b = c + CLASS0_BITS - 1;  /* number of bits */
117       for (i = 0; i < b; ++i)
118         cost += bits_cost[i][((d >> i) & 1)];
119     }
120     if (c == MV_CLASS_0) {
121       cost += class0_fp_cost[d][f];
122     } else {
123       cost += fp_cost[f];
124     }
125     if (usehp) {
126       if (c == MV_CLASS_0) {
127         cost += class0_hp_cost[e];
128       } else {
129         cost += hp_cost[e];
130       }
131     }
132     mvcost[v] = cost + sign_cost[0];
133     mvcost[-v] = cost + sign_cost[1];
134   }
135 }
136 
update_mv(vpx_writer * w,const unsigned int ct[2],vpx_prob * cur_p,vpx_prob upd_p)137 static int update_mv(vpx_writer *w, const unsigned int ct[2], vpx_prob *cur_p,
138                      vpx_prob upd_p) {
139   const vpx_prob new_p = get_binary_prob(ct[0], ct[1]) | 1;
140   const int update = cost_branch256(ct, *cur_p) + vp9_cost_zero(upd_p) >
141                      cost_branch256(ct, new_p) + vp9_cost_one(upd_p) + 7 * 256;
142   vpx_write(w, update, upd_p);
143   if (update) {
144     *cur_p = new_p;
145     vpx_write_literal(w, new_p >> 1, 7);
146   }
147   return update;
148 }
149 
write_mv_update(const vpx_tree_index * tree,vpx_prob probs[],const unsigned int counts[],int n,vpx_writer * w)150 static void write_mv_update(const vpx_tree_index *tree,
151                             vpx_prob probs[/*n - 1*/],
152                             const unsigned int counts[/*n - 1*/],
153                             int n, vpx_writer *w) {
154   int i;
155   unsigned int branch_ct[32][2];
156 
157   // Assuming max number of probabilities <= 32
158   assert(n <= 32);
159 
160   vp9_tree_probs_from_distribution(tree, branch_ct, counts);
161   for (i = 0; i < n - 1; ++i)
162     update_mv(w, branch_ct[i], &probs[i], MV_UPDATE_PROB);
163 }
164 
vp9_write_nmv_probs(VP9_COMMON * cm,int usehp,vpx_writer * w,nmv_context_counts * const counts)165 void vp9_write_nmv_probs(VP9_COMMON *cm, int usehp, vpx_writer *w,
166                          nmv_context_counts *const counts) {
167   int i, j;
168   nmv_context *const mvc = &cm->fc->nmvc;
169 
170   write_mv_update(vp9_mv_joint_tree, mvc->joints, counts->joints, MV_JOINTS, w);
171 
172   for (i = 0; i < 2; ++i) {
173     nmv_component *comp = &mvc->comps[i];
174     nmv_component_counts *comp_counts = &counts->comps[i];
175 
176     update_mv(w, comp_counts->sign, &comp->sign, MV_UPDATE_PROB);
177     write_mv_update(vp9_mv_class_tree, comp->classes, comp_counts->classes,
178                     MV_CLASSES, w);
179     write_mv_update(vp9_mv_class0_tree, comp->class0, comp_counts->class0,
180                     CLASS0_SIZE, w);
181     for (j = 0; j < MV_OFFSET_BITS; ++j)
182       update_mv(w, comp_counts->bits[j], &comp->bits[j], MV_UPDATE_PROB);
183   }
184 
185   for (i = 0; i < 2; ++i) {
186     for (j = 0; j < CLASS0_SIZE; ++j)
187       write_mv_update(vp9_mv_fp_tree, mvc->comps[i].class0_fp[j],
188                       counts->comps[i].class0_fp[j], MV_FP_SIZE, w);
189 
190     write_mv_update(vp9_mv_fp_tree, mvc->comps[i].fp, counts->comps[i].fp,
191                     MV_FP_SIZE, w);
192   }
193 
194   if (usehp) {
195     for (i = 0; i < 2; ++i) {
196       update_mv(w, counts->comps[i].class0_hp, &mvc->comps[i].class0_hp,
197                 MV_UPDATE_PROB);
198       update_mv(w, counts->comps[i].hp, &mvc->comps[i].hp, MV_UPDATE_PROB);
199     }
200   }
201 }
202 
vp9_encode_mv(VP9_COMP * cpi,vpx_writer * w,const MV * mv,const MV * ref,const nmv_context * mvctx,int usehp)203 void vp9_encode_mv(VP9_COMP* cpi, vpx_writer* w,
204                    const MV* mv, const MV* ref,
205                    const nmv_context* mvctx, int usehp) {
206   const MV diff = {mv->row - ref->row,
207                    mv->col - ref->col};
208   const MV_JOINT_TYPE j = vp9_get_mv_joint(&diff);
209   usehp = usehp && vp9_use_mv_hp(ref);
210 
211   vp9_write_token(w, vp9_mv_joint_tree, mvctx->joints, &mv_joint_encodings[j]);
212   if (mv_joint_vertical(j))
213     encode_mv_component(w, diff.row, &mvctx->comps[0], usehp);
214 
215   if (mv_joint_horizontal(j))
216     encode_mv_component(w, diff.col, &mvctx->comps[1], usehp);
217 
218   // If auto_mv_step_size is enabled then keep track of the largest
219   // motion vector component used.
220   if (cpi->sf.mv.auto_mv_step_size) {
221     unsigned int maxv = VPXMAX(abs(mv->row), abs(mv->col)) >> 3;
222     cpi->max_mv_magnitude = VPXMAX(maxv, cpi->max_mv_magnitude);
223   }
224 }
225 
vp9_build_nmv_cost_table(int * mvjoint,int * mvcost[2],const nmv_context * ctx,int usehp)226 void vp9_build_nmv_cost_table(int *mvjoint, int *mvcost[2],
227                               const nmv_context* ctx, int usehp) {
228   vp9_cost_tokens(mvjoint, ctx->joints, vp9_mv_joint_tree);
229   build_nmv_component_cost_table(mvcost[0], &ctx->comps[0], usehp);
230   build_nmv_component_cost_table(mvcost[1], &ctx->comps[1], usehp);
231 }
232 
inc_mvs(const MB_MODE_INFO * mbmi,const MB_MODE_INFO_EXT * mbmi_ext,const int_mv mvs[2],nmv_context_counts * counts)233 static void inc_mvs(const MB_MODE_INFO *mbmi, const MB_MODE_INFO_EXT *mbmi_ext,
234                     const int_mv mvs[2],
235                     nmv_context_counts *counts) {
236   int i;
237 
238   for (i = 0; i < 1 + has_second_ref(mbmi); ++i) {
239     const MV *ref = &mbmi_ext->ref_mvs[mbmi->ref_frame[i]][0].as_mv;
240     const MV diff = {mvs[i].as_mv.row - ref->row,
241                      mvs[i].as_mv.col - ref->col};
242     vp9_inc_mv(&diff, counts);
243   }
244 }
245 
vp9_update_mv_count(ThreadData * td)246 void vp9_update_mv_count(ThreadData *td) {
247   const MACROBLOCKD *xd = &td->mb.e_mbd;
248   const MODE_INFO *mi = xd->mi[0];
249   const MB_MODE_INFO *const mbmi = &mi->mbmi;
250   const MB_MODE_INFO_EXT *mbmi_ext = td->mb.mbmi_ext;
251 
252   if (mbmi->sb_type < BLOCK_8X8) {
253     const int num_4x4_w = num_4x4_blocks_wide_lookup[mbmi->sb_type];
254     const int num_4x4_h = num_4x4_blocks_high_lookup[mbmi->sb_type];
255     int idx, idy;
256 
257     for (idy = 0; idy < 2; idy += num_4x4_h) {
258       for (idx = 0; idx < 2; idx += num_4x4_w) {
259         const int i = idy * 2 + idx;
260         if (mi->bmi[i].as_mode == NEWMV)
261           inc_mvs(mbmi, mbmi_ext, mi->bmi[i].as_mv, &td->counts->mv);
262       }
263     }
264   } else {
265     if (mbmi->mode == NEWMV)
266       inc_mvs(mbmi, mbmi_ext, mbmi->mv, &td->counts->mv);
267   }
268 }
269 
270