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.
15 #include "vpx/vpx_encoder.h"
16 #include "vpx_mem/vpx_mem.h"
17 #include "vpx_ports/mem_ops.h"
19 #include "vp9/common/vp9_entropy.h"
20 #include "vp9/common/vp9_entropymode.h"
21 #include "vp9/common/vp9_entropymv.h"
22 #include "vp9/common/vp9_mvref_common.h"
23 #include "vp9/common/vp9_pred_common.h"
24 #include "vp9/common/vp9_seg_common.h"
25 #include "vp9/common/vp9_systemdependent.h"
26 #include "vp9/common/vp9_tile_common.h"
28 #include "vp9/encoder/vp9_cost.h"
29 #include "vp9/encoder/vp9_bitstream.h"
30 #include "vp9/encoder/vp9_encodemv.h"
31 #include "vp9/encoder/vp9_mcomp.h"
32 #include "vp9/encoder/vp9_segmentation.h"
33 #include "vp9/encoder/vp9_subexp.h"
34 #include "vp9/encoder/vp9_tokenize.h"
35 #include "vp9/encoder/vp9_write_bit_buffer.h"
37 static struct vp9_token intra_mode_encodings[INTRA_MODES];
38 static struct vp9_token switchable_interp_encodings[SWITCHABLE_FILTERS];
39 static struct vp9_token partition_encodings[PARTITION_TYPES];
40 static struct vp9_token inter_mode_encodings[INTER_MODES];
42 void vp9_entropy_mode_init() {
43 vp9_tokens_from_tree(intra_mode_encodings, vp9_intra_mode_tree);
44 vp9_tokens_from_tree(switchable_interp_encodings, vp9_switchable_interp_tree);
45 vp9_tokens_from_tree(partition_encodings, vp9_partition_tree);
46 vp9_tokens_from_tree(inter_mode_encodings, vp9_inter_mode_tree);
49 static void write_intra_mode(vp9_writer *w, PREDICTION_MODE mode,
50 const vp9_prob *probs) {
51 vp9_write_token(w, vp9_intra_mode_tree, probs, &intra_mode_encodings[mode]);
54 static void write_inter_mode(vp9_writer *w, PREDICTION_MODE mode,
55 const vp9_prob *probs) {
56 assert(is_inter_mode(mode));
57 vp9_write_token(w, vp9_inter_mode_tree, probs,
58 &inter_mode_encodings[INTER_OFFSET(mode)]);
61 static void encode_unsigned_max(struct vp9_write_bit_buffer *wb,
63 vp9_wb_write_literal(wb, data, get_unsigned_bits(max));
66 static void prob_diff_update(const vp9_tree_index *tree,
67 vp9_prob probs[/*n - 1*/],
68 const unsigned int counts[/*n - 1*/],
69 int n, vp9_writer *w) {
71 unsigned int branch_ct[32][2];
73 // Assuming max number of probabilities <= 32
76 vp9_tree_probs_from_distribution(tree, branch_ct, counts);
77 for (i = 0; i < n - 1; ++i)
78 vp9_cond_prob_diff_update(w, &probs[i], branch_ct[i]);
81 static void write_selected_tx_size(const VP9_COMMON *cm,
82 const MACROBLOCKD *xd, vp9_writer *w) {
83 TX_SIZE tx_size = xd->mi[0].src_mi->mbmi.tx_size;
84 BLOCK_SIZE bsize = xd->mi[0].src_mi->mbmi.sb_type;
85 const TX_SIZE max_tx_size = max_txsize_lookup[bsize];
86 const vp9_prob *const tx_probs = get_tx_probs2(max_tx_size, xd,
88 vp9_write(w, tx_size != TX_4X4, tx_probs[0]);
89 if (tx_size != TX_4X4 && max_tx_size >= TX_16X16) {
90 vp9_write(w, tx_size != TX_8X8, tx_probs[1]);
91 if (tx_size != TX_8X8 && max_tx_size >= TX_32X32)
92 vp9_write(w, tx_size != TX_16X16, tx_probs[2]);
96 static int write_skip(const VP9_COMMON *cm, const MACROBLOCKD *xd,
97 int segment_id, const MODE_INFO *mi, vp9_writer *w) {
98 if (vp9_segfeature_active(&cm->seg, segment_id, SEG_LVL_SKIP)) {
101 const int skip = mi->mbmi.skip;
102 vp9_write(w, skip, vp9_get_skip_prob(cm, xd));
107 static void update_skip_probs(VP9_COMMON *cm, vp9_writer *w,
108 FRAME_COUNTS *counts) {
111 for (k = 0; k < SKIP_CONTEXTS; ++k)
112 vp9_cond_prob_diff_update(w, &cm->fc->skip_probs[k], counts->skip[k]);
115 static void update_switchable_interp_probs(VP9_COMMON *cm, vp9_writer *w,
116 FRAME_COUNTS *counts) {
118 for (j = 0; j < SWITCHABLE_FILTER_CONTEXTS; ++j)
119 prob_diff_update(vp9_switchable_interp_tree,
120 cm->fc->switchable_interp_prob[j],
121 counts->switchable_interp[j], SWITCHABLE_FILTERS, w);
124 static void pack_mb_tokens(vp9_writer *w,
125 TOKENEXTRA **tp, const TOKENEXTRA *const stop,
126 vpx_bit_depth_t bit_depth) {
129 while (p < stop && p->token != EOSB_TOKEN) {
130 const int t = p->token;
131 const struct vp9_token *const a = &vp9_coef_encodings[t];
135 #if CONFIG_VP9_HIGHBITDEPTH
136 const vp9_extra_bit *b;
137 if (bit_depth == VPX_BITS_12)
138 b = &vp9_extra_bits_high12[t];
139 else if (bit_depth == VPX_BITS_10)
140 b = &vp9_extra_bits_high10[t];
142 b = &vp9_extra_bits[t];
144 const vp9_extra_bit *const b = &vp9_extra_bits[t];
146 #endif // CONFIG_VP9_HIGHBITDEPTH
148 /* skip one or two nodes */
149 if (p->skip_eob_node) {
150 n -= p->skip_eob_node;
151 i = 2 * p->skip_eob_node;
154 // TODO(jbb): expanding this can lead to big gains. It allows
155 // much better branch prediction and would enable us to avoid numerous
156 // lookups and compares.
158 // If we have a token that's in the constrained set, the coefficient tree
159 // is split into two treed writes. The first treed write takes care of the
160 // unconstrained nodes. The second treed write takes care of the
161 // constrained nodes.
162 if (t >= TWO_TOKEN && t < EOB_TOKEN) {
163 int len = UNCONSTRAINED_NODES - p->skip_eob_node;
164 int bits = v >> (n - len);
165 vp9_write_tree(w, vp9_coef_tree, p->context_tree, bits, len, i);
166 vp9_write_tree(w, vp9_coef_con_tree,
167 vp9_pareto8_full[p->context_tree[PIVOT_NODE] - 1],
170 vp9_write_tree(w, vp9_coef_tree, p->context_tree, v, n, i);
174 const int e = p->extra, l = b->len;
177 const unsigned char *pb = b->prob;
179 int n = l; /* number of bits in v, assumed nonzero */
183 const int bb = (v >> --n) & 1;
184 vp9_write(w, bb, pb[i >> 1]);
189 vp9_write_bit(w, e & 1);
194 *tp = p + (p->token == EOSB_TOKEN);
197 static void write_segment_id(vp9_writer *w, const struct segmentation *seg,
199 if (seg->enabled && seg->update_map)
200 vp9_write_tree(w, vp9_segment_tree, seg->tree_probs, segment_id, 3, 0);
203 // This function encodes the reference frame
204 static void write_ref_frames(const VP9_COMMON *cm, const MACROBLOCKD *xd,
206 const MB_MODE_INFO *const mbmi = &xd->mi[0].src_mi->mbmi;
207 const int is_compound = has_second_ref(mbmi);
208 const int segment_id = mbmi->segment_id;
210 // If segment level coding of this signal is disabled...
211 // or the segment allows multiple reference frame options
212 if (vp9_segfeature_active(&cm->seg, segment_id, SEG_LVL_REF_FRAME)) {
213 assert(!is_compound);
214 assert(mbmi->ref_frame[0] ==
215 vp9_get_segdata(&cm->seg, segment_id, SEG_LVL_REF_FRAME));
217 // does the feature use compound prediction or not
218 // (if not specified at the frame/segment level)
219 if (cm->reference_mode == REFERENCE_MODE_SELECT) {
220 vp9_write(w, is_compound, vp9_get_reference_mode_prob(cm, xd));
222 assert(!is_compound == (cm->reference_mode == SINGLE_REFERENCE));
226 vp9_write(w, mbmi->ref_frame[0] == GOLDEN_FRAME,
227 vp9_get_pred_prob_comp_ref_p(cm, xd));
229 const int bit0 = mbmi->ref_frame[0] != LAST_FRAME;
230 vp9_write(w, bit0, vp9_get_pred_prob_single_ref_p1(cm, xd));
232 const int bit1 = mbmi->ref_frame[0] != GOLDEN_FRAME;
233 vp9_write(w, bit1, vp9_get_pred_prob_single_ref_p2(cm, xd));
239 static void pack_inter_mode_mvs(VP9_COMP *cpi, const MODE_INFO *mi,
241 VP9_COMMON *const cm = &cpi->common;
242 const nmv_context *nmvc = &cm->fc->nmvc;
243 const MACROBLOCK *const x = &cpi->td.mb;
244 const MACROBLOCKD *const xd = &x->e_mbd;
245 const struct segmentation *const seg = &cm->seg;
246 const MB_MODE_INFO *const mbmi = &mi->mbmi;
247 const PREDICTION_MODE mode = mbmi->mode;
248 const int segment_id = mbmi->segment_id;
249 const BLOCK_SIZE bsize = mbmi->sb_type;
250 const int allow_hp = cm->allow_high_precision_mv;
251 const int is_inter = is_inter_block(mbmi);
252 const int is_compound = has_second_ref(mbmi);
255 if (seg->update_map) {
256 if (seg->temporal_update) {
257 const int pred_flag = mbmi->seg_id_predicted;
258 vp9_prob pred_prob = vp9_get_pred_prob_seg_id(seg, xd);
259 vp9_write(w, pred_flag, pred_prob);
261 write_segment_id(w, seg, segment_id);
263 write_segment_id(w, seg, segment_id);
267 skip = write_skip(cm, xd, segment_id, mi, w);
269 if (!vp9_segfeature_active(seg, segment_id, SEG_LVL_REF_FRAME))
270 vp9_write(w, is_inter, vp9_get_intra_inter_prob(cm, xd));
272 if (bsize >= BLOCK_8X8 && cm->tx_mode == TX_MODE_SELECT &&
274 (skip || vp9_segfeature_active(seg, segment_id, SEG_LVL_SKIP)))) {
275 write_selected_tx_size(cm, xd, w);
279 if (bsize >= BLOCK_8X8) {
280 write_intra_mode(w, mode, cm->fc->y_mode_prob[size_group_lookup[bsize]]);
283 const int num_4x4_w = num_4x4_blocks_wide_lookup[bsize];
284 const int num_4x4_h = num_4x4_blocks_high_lookup[bsize];
285 for (idy = 0; idy < 2; idy += num_4x4_h) {
286 for (idx = 0; idx < 2; idx += num_4x4_w) {
287 const PREDICTION_MODE b_mode = mi->bmi[idy * 2 + idx].as_mode;
288 write_intra_mode(w, b_mode, cm->fc->y_mode_prob[0]);
292 write_intra_mode(w, mbmi->uv_mode, cm->fc->uv_mode_prob[mode]);
294 const int mode_ctx = mbmi->mode_context[mbmi->ref_frame[0]];
295 const vp9_prob *const inter_probs = cm->fc->inter_mode_probs[mode_ctx];
296 write_ref_frames(cm, xd, w);
298 // If segment skip is not enabled code the mode.
299 if (!vp9_segfeature_active(seg, segment_id, SEG_LVL_SKIP)) {
300 if (bsize >= BLOCK_8X8) {
301 write_inter_mode(w, mode, inter_probs);
302 ++cpi->td.counts->inter_mode[mode_ctx][INTER_OFFSET(mode)];
306 if (cm->interp_filter == SWITCHABLE) {
307 const int ctx = vp9_get_pred_context_switchable_interp(xd);
308 vp9_write_token(w, vp9_switchable_interp_tree,
309 cm->fc->switchable_interp_prob[ctx],
310 &switchable_interp_encodings[mbmi->interp_filter]);
311 ++cpi->interp_filter_selected[0][mbmi->interp_filter];
313 assert(mbmi->interp_filter == cm->interp_filter);
316 if (bsize < BLOCK_8X8) {
317 const int num_4x4_w = num_4x4_blocks_wide_lookup[bsize];
318 const int num_4x4_h = num_4x4_blocks_high_lookup[bsize];
320 for (idy = 0; idy < 2; idy += num_4x4_h) {
321 for (idx = 0; idx < 2; idx += num_4x4_w) {
322 const int j = idy * 2 + idx;
323 const PREDICTION_MODE b_mode = mi->bmi[j].as_mode;
324 write_inter_mode(w, b_mode, inter_probs);
325 ++cpi->td.counts->inter_mode[mode_ctx][INTER_OFFSET(b_mode)];
326 if (b_mode == NEWMV) {
327 for (ref = 0; ref < 1 + is_compound; ++ref)
328 vp9_encode_mv(cpi, w, &mi->bmi[j].as_mv[ref].as_mv,
329 &mbmi->ref_mvs[mbmi->ref_frame[ref]][0].as_mv,
336 for (ref = 0; ref < 1 + is_compound; ++ref)
337 vp9_encode_mv(cpi, w, &mbmi->mv[ref].as_mv,
338 &mbmi->ref_mvs[mbmi->ref_frame[ref]][0].as_mv, nmvc,
345 static void write_mb_modes_kf(const VP9_COMMON *cm, const MACROBLOCKD *xd,
346 MODE_INFO *mi_8x8, vp9_writer *w) {
347 const struct segmentation *const seg = &cm->seg;
348 const MODE_INFO *const mi = mi_8x8;
349 const MODE_INFO *const above_mi = mi_8x8[-xd->mi_stride].src_mi;
350 const MODE_INFO *const left_mi =
351 xd->left_available ? mi_8x8[-1].src_mi : NULL;
352 const MB_MODE_INFO *const mbmi = &mi->mbmi;
353 const BLOCK_SIZE bsize = mbmi->sb_type;
356 write_segment_id(w, seg, mbmi->segment_id);
358 write_skip(cm, xd, mbmi->segment_id, mi, w);
360 if (bsize >= BLOCK_8X8 && cm->tx_mode == TX_MODE_SELECT)
361 write_selected_tx_size(cm, xd, w);
363 if (bsize >= BLOCK_8X8) {
364 write_intra_mode(w, mbmi->mode, get_y_mode_probs(mi, above_mi, left_mi, 0));
366 const int num_4x4_w = num_4x4_blocks_wide_lookup[bsize];
367 const int num_4x4_h = num_4x4_blocks_high_lookup[bsize];
370 for (idy = 0; idy < 2; idy += num_4x4_h) {
371 for (idx = 0; idx < 2; idx += num_4x4_w) {
372 const int block = idy * 2 + idx;
373 write_intra_mode(w, mi->bmi[block].as_mode,
374 get_y_mode_probs(mi, above_mi, left_mi, block));
379 write_intra_mode(w, mbmi->uv_mode, vp9_kf_uv_mode_prob[mbmi->mode]);
382 static void write_modes_b(VP9_COMP *cpi, const TileInfo *const tile,
383 vp9_writer *w, TOKENEXTRA **tok,
384 const TOKENEXTRA *const tok_end,
385 int mi_row, int mi_col) {
386 const VP9_COMMON *const cm = &cpi->common;
387 MACROBLOCKD *const xd = &cpi->td.mb.e_mbd;
390 xd->mi = cm->mi + (mi_row * cm->mi_stride + mi_col);
393 set_mi_row_col(xd, tile,
394 mi_row, num_8x8_blocks_high_lookup[m->mbmi.sb_type],
395 mi_col, num_8x8_blocks_wide_lookup[m->mbmi.sb_type],
396 cm->mi_rows, cm->mi_cols);
397 if (frame_is_intra_only(cm)) {
398 write_mb_modes_kf(cm, xd, xd->mi, w);
400 pack_inter_mode_mvs(cpi, m, w);
403 assert(*tok < tok_end);
404 pack_mb_tokens(w, tok, tok_end, cm->bit_depth);
407 static void write_partition(const VP9_COMMON *const cm,
408 const MACROBLOCKD *const xd,
409 int hbs, int mi_row, int mi_col,
410 PARTITION_TYPE p, BLOCK_SIZE bsize, vp9_writer *w) {
411 const int ctx = partition_plane_context(xd, mi_row, mi_col, bsize);
412 const vp9_prob *const probs = get_partition_probs(cm, ctx);
413 const int has_rows = (mi_row + hbs) < cm->mi_rows;
414 const int has_cols = (mi_col + hbs) < cm->mi_cols;
416 if (has_rows && has_cols) {
417 vp9_write_token(w, vp9_partition_tree, probs, &partition_encodings[p]);
418 } else if (!has_rows && has_cols) {
419 assert(p == PARTITION_SPLIT || p == PARTITION_HORZ);
420 vp9_write(w, p == PARTITION_SPLIT, probs[1]);
421 } else if (has_rows && !has_cols) {
422 assert(p == PARTITION_SPLIT || p == PARTITION_VERT);
423 vp9_write(w, p == PARTITION_SPLIT, probs[2]);
425 assert(p == PARTITION_SPLIT);
429 static void write_modes_sb(VP9_COMP *cpi,
430 const TileInfo *const tile, vp9_writer *w,
431 TOKENEXTRA **tok, const TOKENEXTRA *const tok_end,
432 int mi_row, int mi_col, BLOCK_SIZE bsize) {
433 const VP9_COMMON *const cm = &cpi->common;
434 MACROBLOCKD *const xd = &cpi->td.mb.e_mbd;
436 const int bsl = b_width_log2_lookup[bsize];
437 const int bs = (1 << bsl) / 4;
438 PARTITION_TYPE partition;
440 const MODE_INFO *m = NULL;
442 if (mi_row >= cm->mi_rows || mi_col >= cm->mi_cols)
445 m = cm->mi[mi_row * cm->mi_stride + mi_col].src_mi;
447 partition = partition_lookup[bsl][m->mbmi.sb_type];
448 write_partition(cm, xd, bs, mi_row, mi_col, partition, bsize, w);
449 subsize = get_subsize(bsize, partition);
450 if (subsize < BLOCK_8X8) {
451 write_modes_b(cpi, tile, w, tok, tok_end, mi_row, mi_col);
455 write_modes_b(cpi, tile, w, tok, tok_end, mi_row, mi_col);
458 write_modes_b(cpi, tile, w, tok, tok_end, mi_row, mi_col);
459 if (mi_row + bs < cm->mi_rows)
460 write_modes_b(cpi, tile, w, tok, tok_end, mi_row + bs, mi_col);
463 write_modes_b(cpi, tile, w, tok, tok_end, mi_row, mi_col);
464 if (mi_col + bs < cm->mi_cols)
465 write_modes_b(cpi, tile, w, tok, tok_end, mi_row, mi_col + bs);
467 case PARTITION_SPLIT:
468 write_modes_sb(cpi, tile, w, tok, tok_end, mi_row, mi_col, subsize);
469 write_modes_sb(cpi, tile, w, tok, tok_end, mi_row, mi_col + bs,
471 write_modes_sb(cpi, tile, w, tok, tok_end, mi_row + bs, mi_col,
473 write_modes_sb(cpi, tile, w, tok, tok_end, mi_row + bs, mi_col + bs,
481 // update partition context
482 if (bsize >= BLOCK_8X8 &&
483 (bsize == BLOCK_8X8 || partition != PARTITION_SPLIT))
484 update_partition_context(xd, mi_row, mi_col, subsize, bsize);
487 static void write_modes(VP9_COMP *cpi,
488 const TileInfo *const tile, vp9_writer *w,
489 TOKENEXTRA **tok, const TOKENEXTRA *const tok_end) {
490 MACROBLOCKD *const xd = &cpi->td.mb.e_mbd;
493 for (mi_row = tile->mi_row_start; mi_row < tile->mi_row_end;
494 mi_row += MI_BLOCK_SIZE) {
495 vp9_zero(xd->left_seg_context);
496 for (mi_col = tile->mi_col_start; mi_col < tile->mi_col_end;
497 mi_col += MI_BLOCK_SIZE)
498 write_modes_sb(cpi, tile, w, tok, tok_end, mi_row, mi_col,
503 static void build_tree_distribution(VP9_COMP *cpi, TX_SIZE tx_size,
504 vp9_coeff_stats *coef_branch_ct,
505 vp9_coeff_probs_model *coef_probs) {
506 vp9_coeff_count *coef_counts = cpi->td.rd_counts.coef_counts[tx_size];
507 unsigned int (*eob_branch_ct)[REF_TYPES][COEF_BANDS][COEFF_CONTEXTS] =
508 cpi->common.counts.eob_branch[tx_size];
511 for (i = 0; i < PLANE_TYPES; ++i) {
512 for (j = 0; j < REF_TYPES; ++j) {
513 for (k = 0; k < COEF_BANDS; ++k) {
514 for (l = 0; l < BAND_COEFF_CONTEXTS(k); ++l) {
515 vp9_tree_probs_from_distribution(vp9_coef_tree,
516 coef_branch_ct[i][j][k][l],
517 coef_counts[i][j][k][l]);
518 coef_branch_ct[i][j][k][l][0][1] = eob_branch_ct[i][j][k][l] -
519 coef_branch_ct[i][j][k][l][0][0];
520 for (m = 0; m < UNCONSTRAINED_NODES; ++m)
521 coef_probs[i][j][k][l][m] = get_binary_prob(
522 coef_branch_ct[i][j][k][l][m][0],
523 coef_branch_ct[i][j][k][l][m][1]);
530 static void update_coef_probs_common(vp9_writer* const bc, VP9_COMP *cpi,
532 vp9_coeff_stats *frame_branch_ct,
533 vp9_coeff_probs_model *new_coef_probs) {
534 vp9_coeff_probs_model *old_coef_probs = cpi->common.fc->coef_probs[tx_size];
535 const vp9_prob upd = DIFF_UPDATE_PROB;
536 const int entropy_nodes_update = UNCONSTRAINED_NODES;
538 switch (cpi->sf.use_fast_coef_updates) {
540 /* dry run to see if there is any update at all needed */
542 int update[2] = {0, 0};
543 for (i = 0; i < PLANE_TYPES; ++i) {
544 for (j = 0; j < REF_TYPES; ++j) {
545 for (k = 0; k < COEF_BANDS; ++k) {
546 for (l = 0; l < BAND_COEFF_CONTEXTS(k); ++l) {
547 for (t = 0; t < entropy_nodes_update; ++t) {
548 vp9_prob newp = new_coef_probs[i][j][k][l][t];
549 const vp9_prob oldp = old_coef_probs[i][j][k][l][t];
553 s = vp9_prob_diff_update_savings_search_model(
554 frame_branch_ct[i][j][k][l][0],
555 old_coef_probs[i][j][k][l], &newp, upd);
557 s = vp9_prob_diff_update_savings_search(
558 frame_branch_ct[i][j][k][l][t], oldp, &newp, upd);
559 if (s > 0 && newp != oldp)
562 savings += s - (int)(vp9_cost_zero(upd));
564 savings -= (int)(vp9_cost_zero(upd));
572 // printf("Update %d %d, savings %d\n", update[0], update[1], savings);
573 /* Is coef updated at all */
574 if (update[1] == 0 || savings < 0) {
575 vp9_write_bit(bc, 0);
578 vp9_write_bit(bc, 1);
579 for (i = 0; i < PLANE_TYPES; ++i) {
580 for (j = 0; j < REF_TYPES; ++j) {
581 for (k = 0; k < COEF_BANDS; ++k) {
582 for (l = 0; l < BAND_COEFF_CONTEXTS(k); ++l) {
583 // calc probs and branch cts for this frame only
584 for (t = 0; t < entropy_nodes_update; ++t) {
585 vp9_prob newp = new_coef_probs[i][j][k][l][t];
586 vp9_prob *oldp = old_coef_probs[i][j][k][l] + t;
587 const vp9_prob upd = DIFF_UPDATE_PROB;
591 s = vp9_prob_diff_update_savings_search_model(
592 frame_branch_ct[i][j][k][l][0],
593 old_coef_probs[i][j][k][l], &newp, upd);
595 s = vp9_prob_diff_update_savings_search(
596 frame_branch_ct[i][j][k][l][t],
598 if (s > 0 && newp != *oldp)
600 vp9_write(bc, u, upd);
602 /* send/use new probability */
603 vp9_write_prob_diff_update(bc, newp, *oldp);
615 case ONE_LOOP_REDUCED: {
616 const int prev_coef_contexts_to_update =
617 cpi->sf.use_fast_coef_updates == ONE_LOOP_REDUCED ?
618 COEFF_CONTEXTS >> 1 : COEFF_CONTEXTS;
619 const int coef_band_to_update =
620 cpi->sf.use_fast_coef_updates == ONE_LOOP_REDUCED ?
621 COEF_BANDS >> 1 : COEF_BANDS;
623 int noupdates_before_first = 0;
624 for (i = 0; i < PLANE_TYPES; ++i) {
625 for (j = 0; j < REF_TYPES; ++j) {
626 for (k = 0; k < COEF_BANDS; ++k) {
627 for (l = 0; l < BAND_COEFF_CONTEXTS(k); ++l) {
628 // calc probs and branch cts for this frame only
629 for (t = 0; t < entropy_nodes_update; ++t) {
630 vp9_prob newp = new_coef_probs[i][j][k][l][t];
631 vp9_prob *oldp = old_coef_probs[i][j][k][l] + t;
634 if (l >= prev_coef_contexts_to_update ||
635 k >= coef_band_to_update) {
639 s = vp9_prob_diff_update_savings_search_model(
640 frame_branch_ct[i][j][k][l][0],
641 old_coef_probs[i][j][k][l], &newp, upd);
643 s = vp9_prob_diff_update_savings_search(
644 frame_branch_ct[i][j][k][l][t],
646 if (s > 0 && newp != *oldp)
650 if (u == 0 && updates == 0) {
651 noupdates_before_first++;
654 if (u == 1 && updates == 1) {
657 vp9_write_bit(bc, 1);
658 for (v = 0; v < noupdates_before_first; ++v)
659 vp9_write(bc, 0, upd);
661 vp9_write(bc, u, upd);
663 /* send/use new probability */
664 vp9_write_prob_diff_update(bc, newp, *oldp);
673 vp9_write_bit(bc, 0); // no updates
683 static void update_coef_probs(VP9_COMP *cpi, vp9_writer* w) {
684 const TX_MODE tx_mode = cpi->common.tx_mode;
685 const TX_SIZE max_tx_size = tx_mode_to_biggest_tx_size[tx_mode];
687 vp9_coeff_stats frame_branch_ct[TX_SIZES][PLANE_TYPES];
688 vp9_coeff_probs_model frame_coef_probs[TX_SIZES][PLANE_TYPES];
690 for (tx_size = TX_4X4; tx_size <= TX_32X32; ++tx_size)
691 build_tree_distribution(cpi, tx_size, frame_branch_ct[tx_size],
692 frame_coef_probs[tx_size]);
694 for (tx_size = TX_4X4; tx_size <= max_tx_size; ++tx_size)
695 update_coef_probs_common(w, cpi, tx_size, frame_branch_ct[tx_size],
696 frame_coef_probs[tx_size]);
699 static void encode_loopfilter(struct loopfilter *lf,
700 struct vp9_write_bit_buffer *wb) {
703 // Encode the loop filter level and type
704 vp9_wb_write_literal(wb, lf->filter_level, 6);
705 vp9_wb_write_literal(wb, lf->sharpness_level, 3);
707 // Write out loop filter deltas applied at the MB level based on mode or
708 // ref frame (if they are enabled).
709 vp9_wb_write_bit(wb, lf->mode_ref_delta_enabled);
711 if (lf->mode_ref_delta_enabled) {
712 vp9_wb_write_bit(wb, lf->mode_ref_delta_update);
713 if (lf->mode_ref_delta_update) {
714 for (i = 0; i < MAX_REF_LF_DELTAS; i++) {
715 const int delta = lf->ref_deltas[i];
716 const int changed = delta != lf->last_ref_deltas[i];
717 vp9_wb_write_bit(wb, changed);
719 lf->last_ref_deltas[i] = delta;
720 vp9_wb_write_literal(wb, abs(delta) & 0x3F, 6);
721 vp9_wb_write_bit(wb, delta < 0);
725 for (i = 0; i < MAX_MODE_LF_DELTAS; i++) {
726 const int delta = lf->mode_deltas[i];
727 const int changed = delta != lf->last_mode_deltas[i];
728 vp9_wb_write_bit(wb, changed);
730 lf->last_mode_deltas[i] = delta;
731 vp9_wb_write_literal(wb, abs(delta) & 0x3F, 6);
732 vp9_wb_write_bit(wb, delta < 0);
739 static void write_delta_q(struct vp9_write_bit_buffer *wb, int delta_q) {
741 vp9_wb_write_bit(wb, 1);
742 vp9_wb_write_literal(wb, abs(delta_q), 4);
743 vp9_wb_write_bit(wb, delta_q < 0);
745 vp9_wb_write_bit(wb, 0);
749 static void encode_quantization(const VP9_COMMON *const cm,
750 struct vp9_write_bit_buffer *wb) {
751 vp9_wb_write_literal(wb, cm->base_qindex, QINDEX_BITS);
752 write_delta_q(wb, cm->y_dc_delta_q);
753 write_delta_q(wb, cm->uv_dc_delta_q);
754 write_delta_q(wb, cm->uv_ac_delta_q);
757 static void encode_segmentation(VP9_COMMON *cm, MACROBLOCKD *xd,
758 struct vp9_write_bit_buffer *wb) {
761 const struct segmentation *seg = &cm->seg;
763 vp9_wb_write_bit(wb, seg->enabled);
768 vp9_wb_write_bit(wb, seg->update_map);
769 if (seg->update_map) {
770 // Select the coding strategy (temporal or spatial)
771 vp9_choose_segmap_coding_method(cm, xd);
772 // Write out probabilities used to decode unpredicted macro-block segments
773 for (i = 0; i < SEG_TREE_PROBS; i++) {
774 const int prob = seg->tree_probs[i];
775 const int update = prob != MAX_PROB;
776 vp9_wb_write_bit(wb, update);
778 vp9_wb_write_literal(wb, prob, 8);
781 // Write out the chosen coding method.
782 vp9_wb_write_bit(wb, seg->temporal_update);
783 if (seg->temporal_update) {
784 for (i = 0; i < PREDICTION_PROBS; i++) {
785 const int prob = seg->pred_probs[i];
786 const int update = prob != MAX_PROB;
787 vp9_wb_write_bit(wb, update);
789 vp9_wb_write_literal(wb, prob, 8);
795 vp9_wb_write_bit(wb, seg->update_data);
796 if (seg->update_data) {
797 vp9_wb_write_bit(wb, seg->abs_delta);
799 for (i = 0; i < MAX_SEGMENTS; i++) {
800 for (j = 0; j < SEG_LVL_MAX; j++) {
801 const int active = vp9_segfeature_active(seg, i, j);
802 vp9_wb_write_bit(wb, active);
804 const int data = vp9_get_segdata(seg, i, j);
805 const int data_max = vp9_seg_feature_data_max(j);
807 if (vp9_is_segfeature_signed(j)) {
808 encode_unsigned_max(wb, abs(data), data_max);
809 vp9_wb_write_bit(wb, data < 0);
811 encode_unsigned_max(wb, data, data_max);
819 static void encode_txfm_probs(VP9_COMMON *cm, vp9_writer *w,
820 FRAME_COUNTS *counts) {
822 vp9_write_literal(w, MIN(cm->tx_mode, ALLOW_32X32), 2);
823 if (cm->tx_mode >= ALLOW_32X32)
824 vp9_write_bit(w, cm->tx_mode == TX_MODE_SELECT);
827 if (cm->tx_mode == TX_MODE_SELECT) {
829 unsigned int ct_8x8p[TX_SIZES - 3][2];
830 unsigned int ct_16x16p[TX_SIZES - 2][2];
831 unsigned int ct_32x32p[TX_SIZES - 1][2];
834 for (i = 0; i < TX_SIZE_CONTEXTS; i++) {
835 tx_counts_to_branch_counts_8x8(counts->tx.p8x8[i], ct_8x8p);
836 for (j = 0; j < TX_SIZES - 3; j++)
837 vp9_cond_prob_diff_update(w, &cm->fc->tx_probs.p8x8[i][j], ct_8x8p[j]);
840 for (i = 0; i < TX_SIZE_CONTEXTS; i++) {
841 tx_counts_to_branch_counts_16x16(counts->tx.p16x16[i], ct_16x16p);
842 for (j = 0; j < TX_SIZES - 2; j++)
843 vp9_cond_prob_diff_update(w, &cm->fc->tx_probs.p16x16[i][j],
847 for (i = 0; i < TX_SIZE_CONTEXTS; i++) {
848 tx_counts_to_branch_counts_32x32(counts->tx.p32x32[i], ct_32x32p);
849 for (j = 0; j < TX_SIZES - 1; j++)
850 vp9_cond_prob_diff_update(w, &cm->fc->tx_probs.p32x32[i][j],
856 static void write_interp_filter(INTERP_FILTER filter,
857 struct vp9_write_bit_buffer *wb) {
858 const int filter_to_literal[] = { 1, 0, 2, 3 };
860 vp9_wb_write_bit(wb, filter == SWITCHABLE);
861 if (filter != SWITCHABLE)
862 vp9_wb_write_literal(wb, filter_to_literal[filter], 2);
865 static void fix_interp_filter(VP9_COMMON *cm, FRAME_COUNTS *counts) {
866 if (cm->interp_filter == SWITCHABLE) {
867 // Check to see if only one of the filters is actually used
868 int count[SWITCHABLE_FILTERS];
870 for (i = 0; i < SWITCHABLE_FILTERS; ++i) {
872 for (j = 0; j < SWITCHABLE_FILTER_CONTEXTS; ++j)
873 count[i] += counts->switchable_interp[j][i];
877 // Only one filter is used. So set the filter at frame level
878 for (i = 0; i < SWITCHABLE_FILTERS; ++i) {
880 cm->interp_filter = i;
888 static void write_tile_info(const VP9_COMMON *const cm,
889 struct vp9_write_bit_buffer *wb) {
890 int min_log2_tile_cols, max_log2_tile_cols, ones;
891 vp9_get_tile_n_bits(cm->mi_cols, &min_log2_tile_cols, &max_log2_tile_cols);
894 ones = cm->log2_tile_cols - min_log2_tile_cols;
896 vp9_wb_write_bit(wb, 1);
898 if (cm->log2_tile_cols < max_log2_tile_cols)
899 vp9_wb_write_bit(wb, 0);
902 vp9_wb_write_bit(wb, cm->log2_tile_rows != 0);
903 if (cm->log2_tile_rows != 0)
904 vp9_wb_write_bit(wb, cm->log2_tile_rows != 1);
907 static int get_refresh_mask(VP9_COMP *cpi) {
908 if (vp9_preserve_existing_gf(cpi)) {
909 // We have decided to preserve the previously existing golden frame as our
910 // new ARF frame. However, in the short term we leave it in the GF slot and,
911 // if we're updating the GF with the current decoded frame, we save it
912 // instead to the ARF slot.
913 // Later, in the function vp9_encoder.c:vp9_update_reference_frames() we
914 // will swap gld_fb_idx and alt_fb_idx to achieve our objective. We do it
915 // there so that it can be done outside of the recode loop.
916 // Note: This is highly specific to the use of ARF as a forward reference,
917 // and this needs to be generalized as other uses are implemented
918 // (like RTC/temporal scalability).
919 return (cpi->refresh_last_frame << cpi->lst_fb_idx) |
920 (cpi->refresh_golden_frame << cpi->alt_fb_idx);
922 int arf_idx = cpi->alt_fb_idx;
923 if ((cpi->oxcf.pass == 2) && cpi->multi_arf_allowed) {
924 const GF_GROUP *const gf_group = &cpi->twopass.gf_group;
925 arf_idx = gf_group->arf_update_idx[gf_group->index];
927 return (cpi->refresh_last_frame << cpi->lst_fb_idx) |
928 (cpi->refresh_golden_frame << cpi->gld_fb_idx) |
929 (cpi->refresh_alt_ref_frame << arf_idx);
933 static size_t encode_tiles(VP9_COMP *cpi, uint8_t *data_ptr) {
934 VP9_COMMON *const cm = &cpi->common;
935 vp9_writer residual_bc;
936 int tile_row, tile_col;
937 TOKENEXTRA *tok[4][1 << 6], *tok_end;
938 size_t total_size = 0;
939 const int tile_cols = 1 << cm->log2_tile_cols;
940 const int tile_rows = 1 << cm->log2_tile_rows;
941 TOKENEXTRA *pre_tok = cpi->tok;
944 vpx_memset(cm->above_seg_context, 0, sizeof(*cm->above_seg_context) *
945 mi_cols_aligned_to_sb(cm->mi_cols));
947 for (tile_row = 0; tile_row < tile_rows; ++tile_row) {
948 for (tile_col = 0; tile_col < tile_cols; ++tile_col) {
949 int tile_idx = tile_row * tile_cols + tile_col;
950 tok[tile_row][tile_col] = pre_tok + tile_tok;
951 pre_tok = tok[tile_row][tile_col];
952 tile_tok = allocated_tokens(cpi->tile_data[tile_idx].tile_info);
956 for (tile_row = 0; tile_row < tile_rows; tile_row++) {
957 for (tile_col = 0; tile_col < tile_cols; tile_col++) {
958 int tile_idx = tile_row * tile_cols + tile_col;
959 tok_end = tok[tile_row][tile_col] + cpi->tok_count[tile_row][tile_col];
961 if (tile_col < tile_cols - 1 || tile_row < tile_rows - 1)
962 vp9_start_encode(&residual_bc, data_ptr + total_size + 4);
964 vp9_start_encode(&residual_bc, data_ptr + total_size);
966 write_modes(cpi, &cpi->tile_data[tile_idx].tile_info,
967 &residual_bc, &tok[tile_row][tile_col], tok_end);
968 assert(tok[tile_row][tile_col] == tok_end);
969 vp9_stop_encode(&residual_bc);
970 if (tile_col < tile_cols - 1 || tile_row < tile_rows - 1) {
972 mem_put_be32(data_ptr + total_size, residual_bc.pos);
976 total_size += residual_bc.pos;
983 static void write_display_size(const VP9_COMMON *cm,
984 struct vp9_write_bit_buffer *wb) {
985 const int scaling_active = cm->width != cm->display_width ||
986 cm->height != cm->display_height;
987 vp9_wb_write_bit(wb, scaling_active);
988 if (scaling_active) {
989 vp9_wb_write_literal(wb, cm->display_width - 1, 16);
990 vp9_wb_write_literal(wb, cm->display_height - 1, 16);
994 static void write_frame_size(const VP9_COMMON *cm,
995 struct vp9_write_bit_buffer *wb) {
996 vp9_wb_write_literal(wb, cm->width - 1, 16);
997 vp9_wb_write_literal(wb, cm->height - 1, 16);
999 write_display_size(cm, wb);
1002 static void write_frame_size_with_refs(VP9_COMP *cpi,
1003 struct vp9_write_bit_buffer *wb) {
1004 VP9_COMMON *const cm = &cpi->common;
1007 MV_REFERENCE_FRAME ref_frame;
1008 for (ref_frame = LAST_FRAME; ref_frame <= ALTREF_FRAME; ++ref_frame) {
1009 YV12_BUFFER_CONFIG *cfg = get_ref_frame_buffer(cpi, ref_frame);
1010 found = cm->width == cfg->y_crop_width &&
1011 cm->height == cfg->y_crop_height;
1013 // Set "found" to 0 for temporal svc and for spatial svc key frame
1015 ((cpi->svc.number_temporal_layers > 1 &&
1016 cpi->oxcf.rc_mode == VPX_CBR) ||
1017 (cpi->svc.number_spatial_layers > 1 &&
1018 cpi->svc.layer_context[cpi->svc.spatial_layer_id].is_key_frame) ||
1019 (is_two_pass_svc(cpi) &&
1020 cpi->svc.encode_empty_frame_state == ENCODING &&
1021 cpi->svc.layer_context[0].frames_from_key_frame <
1022 cpi->svc.number_temporal_layers + 1))) {
1025 vp9_wb_write_bit(wb, found);
1032 vp9_wb_write_literal(wb, cm->width - 1, 16);
1033 vp9_wb_write_literal(wb, cm->height - 1, 16);
1036 write_display_size(cm, wb);
1039 static void write_sync_code(struct vp9_write_bit_buffer *wb) {
1040 vp9_wb_write_literal(wb, VP9_SYNC_CODE_0, 8);
1041 vp9_wb_write_literal(wb, VP9_SYNC_CODE_1, 8);
1042 vp9_wb_write_literal(wb, VP9_SYNC_CODE_2, 8);
1045 static void write_profile(BITSTREAM_PROFILE profile,
1046 struct vp9_write_bit_buffer *wb) {
1049 vp9_wb_write_literal(wb, 0, 2);
1052 vp9_wb_write_literal(wb, 2, 2);
1055 vp9_wb_write_literal(wb, 1, 2);
1058 vp9_wb_write_literal(wb, 6, 3);
1065 static void write_bitdepth_colorspace_sampling(
1066 VP9_COMMON *const cm, struct vp9_write_bit_buffer *wb) {
1067 if (cm->profile >= PROFILE_2) {
1068 assert(cm->bit_depth > VPX_BITS_8);
1069 vp9_wb_write_bit(wb, cm->bit_depth == VPX_BITS_10 ? 0 : 1);
1071 vp9_wb_write_literal(wb, cm->color_space, 3);
1072 if (cm->color_space != SRGB) {
1073 vp9_wb_write_bit(wb, 0); // 0: [16, 235] (i.e. xvYCC), 1: [0, 255]
1074 if (cm->profile == PROFILE_1 || cm->profile == PROFILE_3) {
1075 assert(cm->subsampling_x != 1 || cm->subsampling_y != 1);
1076 vp9_wb_write_bit(wb, cm->subsampling_x);
1077 vp9_wb_write_bit(wb, cm->subsampling_y);
1078 vp9_wb_write_bit(wb, 0); // unused
1080 assert(cm->subsampling_x == 1 && cm->subsampling_y == 1);
1083 assert(cm->profile == PROFILE_1 || cm->profile == PROFILE_3);
1084 vp9_wb_write_bit(wb, 0); // unused
1088 static void write_uncompressed_header(VP9_COMP *cpi,
1089 struct vp9_write_bit_buffer *wb) {
1090 VP9_COMMON *const cm = &cpi->common;
1091 MACROBLOCKD *const xd = &cpi->td.mb.e_mbd;
1093 vp9_wb_write_literal(wb, VP9_FRAME_MARKER, 2);
1095 write_profile(cm->profile, wb);
1097 vp9_wb_write_bit(wb, 0); // show_existing_frame
1098 vp9_wb_write_bit(wb, cm->frame_type);
1099 vp9_wb_write_bit(wb, cm->show_frame);
1100 vp9_wb_write_bit(wb, cm->error_resilient_mode);
1102 if (cm->frame_type == KEY_FRAME) {
1103 write_sync_code(wb);
1104 write_bitdepth_colorspace_sampling(cm, wb);
1105 write_frame_size(cm, wb);
1107 // In spatial svc if it's not error_resilient_mode then we need to code all
1108 // visible frames as invisible. But we need to keep the show_frame flag so
1109 // that the publisher could know whether it is supposed to be visible.
1110 // So we will code the show_frame flag as it is. Then code the intra_only
1111 // bit here. This will make the bitstream incompatible. In the player we
1112 // will change to show_frame flag to 0, then add an one byte frame with
1113 // show_existing_frame flag which tells the decoder which frame we want to
1115 if (!cm->show_frame)
1116 vp9_wb_write_bit(wb, cm->intra_only);
1118 if (!cm->error_resilient_mode)
1119 vp9_wb_write_literal(wb, cm->reset_frame_context, 2);
1121 if (cm->intra_only) {
1122 write_sync_code(wb);
1124 // Note for profile 0, 420 8bpp is assumed.
1125 if (cm->profile > PROFILE_0) {
1126 write_bitdepth_colorspace_sampling(cm, wb);
1129 vp9_wb_write_literal(wb, get_refresh_mask(cpi), REF_FRAMES);
1130 write_frame_size(cm, wb);
1132 MV_REFERENCE_FRAME ref_frame;
1133 vp9_wb_write_literal(wb, get_refresh_mask(cpi), REF_FRAMES);
1134 for (ref_frame = LAST_FRAME; ref_frame <= ALTREF_FRAME; ++ref_frame) {
1135 vp9_wb_write_literal(wb, get_ref_frame_idx(cpi, ref_frame),
1137 vp9_wb_write_bit(wb, cm->ref_frame_sign_bias[ref_frame]);
1140 write_frame_size_with_refs(cpi, wb);
1142 vp9_wb_write_bit(wb, cm->allow_high_precision_mv);
1144 fix_interp_filter(cm, cpi->td.counts);
1145 write_interp_filter(cm->interp_filter, wb);
1149 if (!cm->error_resilient_mode) {
1150 vp9_wb_write_bit(wb, cm->refresh_frame_context);
1151 vp9_wb_write_bit(wb, cm->frame_parallel_decoding_mode);
1154 vp9_wb_write_literal(wb, cm->frame_context_idx, FRAME_CONTEXTS_LOG2);
1156 encode_loopfilter(&cm->lf, wb);
1157 encode_quantization(cm, wb);
1158 encode_segmentation(cm, xd, wb);
1160 write_tile_info(cm, wb);
1163 static size_t write_compressed_header(VP9_COMP *cpi, uint8_t *data) {
1164 VP9_COMMON *const cm = &cpi->common;
1165 MACROBLOCKD *const xd = &cpi->td.mb.e_mbd;
1166 FRAME_CONTEXT *const fc = cm->fc;
1167 FRAME_COUNTS *counts = cpi->td.counts;
1168 vp9_writer header_bc;
1170 vp9_start_encode(&header_bc, data);
1173 cm->tx_mode = ONLY_4X4;
1175 encode_txfm_probs(cm, &header_bc, counts);
1177 update_coef_probs(cpi, &header_bc);
1178 update_skip_probs(cm, &header_bc, counts);
1180 if (!frame_is_intra_only(cm)) {
1183 for (i = 0; i < INTER_MODE_CONTEXTS; ++i)
1184 prob_diff_update(vp9_inter_mode_tree, cm->fc->inter_mode_probs[i],
1185 counts->inter_mode[i], INTER_MODES, &header_bc);
1187 vp9_zero(counts->inter_mode);
1189 if (cm->interp_filter == SWITCHABLE)
1190 update_switchable_interp_probs(cm, &header_bc, counts);
1192 for (i = 0; i < INTRA_INTER_CONTEXTS; i++)
1193 vp9_cond_prob_diff_update(&header_bc, &fc->intra_inter_prob[i],
1194 counts->intra_inter[i]);
1196 if (cm->allow_comp_inter_inter) {
1197 const int use_compound_pred = cm->reference_mode != SINGLE_REFERENCE;
1198 const int use_hybrid_pred = cm->reference_mode == REFERENCE_MODE_SELECT;
1200 vp9_write_bit(&header_bc, use_compound_pred);
1201 if (use_compound_pred) {
1202 vp9_write_bit(&header_bc, use_hybrid_pred);
1203 if (use_hybrid_pred)
1204 for (i = 0; i < COMP_INTER_CONTEXTS; i++)
1205 vp9_cond_prob_diff_update(&header_bc, &fc->comp_inter_prob[i],
1206 counts->comp_inter[i]);
1210 if (cm->reference_mode != COMPOUND_REFERENCE) {
1211 for (i = 0; i < REF_CONTEXTS; i++) {
1212 vp9_cond_prob_diff_update(&header_bc, &fc->single_ref_prob[i][0],
1213 counts->single_ref[i][0]);
1214 vp9_cond_prob_diff_update(&header_bc, &fc->single_ref_prob[i][1],
1215 counts->single_ref[i][1]);
1219 if (cm->reference_mode != SINGLE_REFERENCE)
1220 for (i = 0; i < REF_CONTEXTS; i++)
1221 vp9_cond_prob_diff_update(&header_bc, &fc->comp_ref_prob[i],
1222 counts->comp_ref[i]);
1224 for (i = 0; i < BLOCK_SIZE_GROUPS; ++i)
1225 prob_diff_update(vp9_intra_mode_tree, cm->fc->y_mode_prob[i],
1226 counts->y_mode[i], INTRA_MODES, &header_bc);
1228 for (i = 0; i < PARTITION_CONTEXTS; ++i)
1229 prob_diff_update(vp9_partition_tree, fc->partition_prob[i],
1230 counts->partition[i], PARTITION_TYPES, &header_bc);
1232 vp9_write_nmv_probs(cm, cm->allow_high_precision_mv, &header_bc,
1236 vp9_stop_encode(&header_bc);
1237 assert(header_bc.pos <= 0xffff);
1239 return header_bc.pos;
1242 void vp9_pack_bitstream(VP9_COMP *cpi, uint8_t *dest, size_t *size) {
1243 uint8_t *data = dest;
1244 size_t first_part_size, uncompressed_hdr_size;
1245 struct vp9_write_bit_buffer wb = {data, 0};
1246 struct vp9_write_bit_buffer saved_wb;
1248 write_uncompressed_header(cpi, &wb);
1250 vp9_wb_write_literal(&wb, 0, 16); // don't know in advance first part. size
1252 uncompressed_hdr_size = vp9_wb_bytes_written(&wb);
1253 data += uncompressed_hdr_size;
1255 vp9_clear_system_state();
1257 first_part_size = write_compressed_header(cpi, data);
1258 data += first_part_size;
1259 // TODO(jbb): Figure out what to do if first_part_size > 16 bits.
1260 vp9_wb_write_literal(&saved_wb, (int)first_part_size, 16);
1262 data += encode_tiles(cpi, data);
1264 *size = data - dest;