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 "vp8/common/common.h"
14 #include "vp8/common/entropymode.h"
15 #include "vp8/common/systemdependent.h"
20 extern unsigned int active_section;
23 static void encode_mvcomponent(
26 const struct mv_context *mvc
29 const vp8_prob *p = mvc->prob;
30 const int x = v < 0 ? -v : v;
32 if (x < mvnum_short) // Small
34 vp8_write(w, 0, p [mvpis_short]);
35 vp8_treed_write(w, vp8_small_mvtree, p + MVPshort, x, 3);
38 return; // no sign bit
44 vp8_write(w, 1, p [mvpis_short]);
47 vp8_write(w, (x >> i) & 1, p [MVPbits + i]);
51 i = mvlong_width - 1; /* Skip bit 3, which is sometimes implicit */
54 vp8_write(w, (x >> i) & 1, p [MVPbits + i]);
59 vp8_write(w, (x >> 3) & 1, p [MVPbits + 3]);
62 vp8_write(w, v < 0, p [MVPsign]);
65 static int max_mv_r = 0;
66 static int max_mv_c = 0;
68 void vp8_encode_motion_vector(vp8_writer *w, const MV *mv, const MV_CONTEXT *mvc)
73 if (abs(mv->row >> 1) > max_mv_r)
75 FILE *f = fopen("maxmv.stt", "a");
76 max_mv_r = abs(mv->row >> 1);
77 fprintf(f, "New Mv Row Max %6d\n", (mv->row >> 1));
79 if ((abs(mv->row) / 2) != max_mv_r)
80 fprintf(f, "MV Row conversion error %6d\n", abs(mv->row) / 2);
85 if (abs(mv->col >> 1) > max_mv_c)
87 FILE *f = fopen("maxmv.stt", "a");
88 fprintf(f, "New Mv Col Max %6d\n", (mv->col >> 1));
89 max_mv_c = abs(mv->col >> 1);
95 encode_mvcomponent(w, mv->row >> 1, &mvc[0]);
96 encode_mvcomponent(w, mv->col >> 1, &mvc[1]);
100 static unsigned int cost_mvcomponent(const int v, const struct mv_context *mvc)
102 const vp8_prob *p = mvc->prob;
103 const int x = v; //v<0? -v:v;
108 cost = vp8_cost_zero(p [mvpis_short])
109 + vp8_treed_cost(vp8_small_mvtree, p + MVPshort, x, 3);
117 cost = vp8_cost_one(p [mvpis_short]);
120 cost += vp8_cost_bit(p [MVPbits + i], (x >> i) & 1);
124 i = mvlong_width - 1; /* Skip bit 3, which is sometimes implicit */
127 cost += vp8_cost_bit(p [MVPbits + i], (x >> i) & 1);
132 cost += vp8_cost_bit(p [MVPbits + 3], (x >> 3) & 1);
135 return cost; // + vp8_cost_bit( p [MVPsign], v < 0);
138 void vp8_build_component_cost_table(int *mvcost[2], const MV_CONTEXT *mvc, int mvc_flag[2])
140 int i = 1; //-mv_max;
141 unsigned int cost0 = 0;
142 unsigned int cost1 = 0;
144 vp8_clear_system_state();
150 mvcost [0] [0] = cost_mvcomponent(0, &mvc[0]);
154 //mvcost [0] [i] = cost_mvcomponent( i, &mvc[0]);
155 cost0 = cost_mvcomponent(i, &mvc[0]);
157 mvcost [0] [i] = cost0 + vp8_cost_zero(mvc[0].prob[MVPsign]);
158 mvcost [0] [-i] = cost0 + vp8_cost_one(mvc[0].prob[MVPsign]);
160 while (++i <= mv_max);
167 mvcost [1] [0] = cost_mvcomponent(0, &mvc[1]);
171 //mvcost [1] [i] = cost_mvcomponent( i, mvc[1]);
172 cost1 = cost_mvcomponent(i, &mvc[1]);
174 mvcost [1] [i] = cost1 + vp8_cost_zero(mvc[1].prob[MVPsign]);
175 mvcost [1] [-i] = cost1 + vp8_cost_one(mvc[1].prob[MVPsign]);
177 while (++i <= mv_max);
182 // Motion vector probability table update depends on benefit.
183 // Small correction allows for the fact that an update to an MV probability
184 // may have benefit in subsequent frames as well as the current one.
186 #define MV_PROB_UPDATE_CORRECTION -1
189 static void calc_prob(vp8_prob *p, const unsigned int ct[2])
191 const unsigned int tot = ct[0] + ct[1];
195 const vp8_prob x = ((ct[0] * 255) / tot) & -2;
202 const unsigned int ct[2],
203 vp8_prob *const cur_p,
204 const vp8_prob new_p,
205 const vp8_prob update_p,
209 const int cur_b = vp8_cost_branch(ct, *cur_p);
210 const int new_b = vp8_cost_branch(ct, new_p);
211 const int cost = 7 + MV_PROB_UPDATE_CORRECTION + ((vp8_cost_one(update_p) - vp8_cost_zero(update_p) + 128) >> 8);
213 if (cur_b - new_b > cost)
216 vp8_write(w, 1, update_p);
217 vp8_write_literal(w, new_p >> 1, 7);
222 vp8_write(w, 0, update_p);
225 static void write_component_probs(
227 struct mv_context *cur_mvc,
228 const struct mv_context *default_mvc_,
229 const struct mv_context *update_mvc,
230 const unsigned int events [MVvals],
235 vp8_prob *Pcur = cur_mvc->prob;
236 const vp8_prob *default_mvc = default_mvc_->prob;
237 const vp8_prob *Pupdate = update_mvc->prob;
238 unsigned int is_short_ct[2], sign_ct[2];
240 unsigned int bit_ct [mvlong_width] [2];
242 unsigned int short_ct [mvnum_short];
243 unsigned int short_bct [mvnum_short-1] [2];
245 vp8_prob Pnew [MVPcount];
248 vp8_copy_array(Pnew, default_mvc, MVPcount);
250 vp8_zero(is_short_ct)
259 const int c = events [mv_max];
261 is_short_ct [0] += c; // Short vector
262 short_ct [0] += c; // Magnitude distribution
265 //j: 1 ~ mv_max (1023)
271 const int c1 = events [mv_max + j]; //positive
272 const int c2 = events [mv_max - j]; //negative
273 const int c = c1 + c2;
281 is_short_ct [0] += c; // Short vector
282 short_ct [a] += c; // Magnitude distribution
286 int k = mvlong_width - 1;
287 is_short_ct [1] += c; // Long vector
289 /* bit 3 not always encoded. */
291 bit_ct [k] [(a >> k) & 1] += c;
296 while (++j <= mv_max);
305 const int c = events [mv_max + j];
318 is_short_ct [0] += c; // Short vector
319 short_ct [a] += c; // Magnitude distribution
323 int k = mvlong_width - 1;
324 is_short_ct [1] += c; // Long vector
326 // bit 3 not always encoded.
329 bit_ct [k] [(a >> k) & 1] += c;
332 } while( ++j <= mv_max);
336 calc_prob(Pnew + mvpis_short, is_short_ct);
338 calc_prob(Pnew + MVPsign, sign_ct);
341 vp8_prob p [mvnum_short - 1]; /* actually only need branch ct */
344 vp8_tree_probs_from_distribution(
345 8, vp8_small_mvencodings, vp8_small_mvtree,
346 p, short_bct, short_ct,
351 calc_prob(Pnew + MVPshort + j, short_bct[j]);
353 while (++j < mvnum_short - 1);
360 calc_prob(Pnew + MVPbits + j, bit_ct[j]);
362 while (++j < mvlong_width);
365 update(w, is_short_ct, Pcur + mvpis_short, Pnew[mvpis_short], *Pupdate++, updated);
367 update(w, sign_ct, Pcur + MVPsign, Pnew[MVPsign], *Pupdate++, updated);
370 const vp8_prob *const new_p = Pnew + MVPshort;
371 vp8_prob *const cur_p = Pcur + MVPshort;
377 update(w, short_bct[j], cur_p + j, new_p[j], *Pupdate++, updated);
379 while (++j < mvnum_short - 1);
383 const vp8_prob *const new_p = Pnew + MVPbits;
384 vp8_prob *const cur_p = Pcur + MVPbits;
390 update(w, bit_ct[j], cur_p + j, new_p[j], *Pupdate++, updated);
392 while (++j < mvlong_width);
396 void vp8_write_mvprobs(VP8_COMP *cpi)
398 vp8_writer *const w = cpi->bc;
399 MV_CONTEXT *mvc = cpi->common.fc.mvc;
400 int flags[2] = {0, 0};
404 write_component_probs(
405 w, &mvc[0], &vp8_default_mv_context[0], &vp8_mv_update_probs[0], cpi->MVcount[0], 0, &flags[0]
407 write_component_probs(
408 w, &mvc[1], &vp8_default_mv_context[1], &vp8_mv_update_probs[1], cpi->MVcount[1], 1, &flags[1]
411 if (flags[0] || flags[1])
412 vp8_build_component_cost_table(cpi->mb.mvcost, (const MV_CONTEXT *) cpi->common.fc.mvc, flags);