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_scale_rtcd.h"
17 #include "vpx_mem/vpx_mem.h"
18 #include "vpx_scale/vpx_scale.h"
19 #include "vpx_scale/yv12config.h"
21 #include "vp9/common/vp9_entropymv.h"
22 #include "vp9/common/vp9_quant_common.h"
23 #include "vp9/common/vp9_reconinter.h" // vp9_setup_dst_planes()
24 #include "vp9/common/vp9_systemdependent.h"
26 #include "vp9/encoder/vp9_aq_variance.h"
27 #include "vp9/encoder/vp9_block.h"
28 #include "vp9/encoder/vp9_encodeframe.h"
29 #include "vp9/encoder/vp9_encodemb.h"
30 #include "vp9/encoder/vp9_encodemv.h"
31 #include "vp9/encoder/vp9_encoder.h"
32 #include "vp9/encoder/vp9_extend.h"
33 #include "vp9/encoder/vp9_firstpass.h"
34 #include "vp9/encoder/vp9_mcomp.h"
35 #include "vp9/encoder/vp9_quantize.h"
36 #include "vp9/encoder/vp9_rdopt.h"
37 #include "vp9/encoder/vp9_variance.h"
42 #define IIKFACTOR1 12.5
43 #define IIKFACTOR2 15.0
46 #define ERR_DIVISOR 150.0
47 #define MIN_DECAY_FACTOR 0.1
48 #define SVC_FACTOR_PT_LOW 0.45
49 #define FACTOR_PT_LOW 0.5
50 #define FACTOR_PT_HIGH 0.9
52 #define KF_MB_INTRA_MIN 150
53 #define GF_MB_INTRA_MIN 100
55 #define DOUBLE_DIVIDE_CHECK(x) ((x) < 0 ? (x) - 0.000001 : (x) + 0.000001)
57 #define MIN_KF_BOOST 300
58 #define MIN_GF_INTERVAL 4
59 #define LONG_TERM_VBR_CORRECTION
61 static void swap_yv12(YV12_BUFFER_CONFIG *a, YV12_BUFFER_CONFIG *b) {
62 YV12_BUFFER_CONFIG temp = *a;
67 static int gfboost_qadjust(int qindex) {
68 const double q = vp9_convert_qindex_to_q(qindex);
69 return (int)((0.00000828 * q * q * q) +
74 // Resets the first pass file to the given position using a relative seek from
75 // the current position.
76 static void reset_fpf_position(TWO_PASS *p,
77 const FIRSTPASS_STATS *position) {
78 p->stats_in = position;
81 static int lookup_next_frame_stats(const TWO_PASS *p,
82 FIRSTPASS_STATS *next_frame) {
83 if (p->stats_in >= p->stats_in_end)
86 *next_frame = *p->stats_in;
91 // Read frame stats at an offset from the current position.
92 static const FIRSTPASS_STATS *read_frame_stats(const TWO_PASS *p, int offset) {
93 if ((offset >= 0 && p->stats_in + offset >= p->stats_in_end) ||
94 (offset < 0 && p->stats_in + offset < p->stats_in_start)) {
98 return &p->stats_in[offset];
101 #if CONFIG_FP_MB_STATS
102 static int input_mb_stats(FIRSTPASS_FRAME_MB_STATS *fp_frame_stats,
103 const VP9_COMMON *const cm) {
107 fpfile = fopen("firstpass_mb.stt", "r");
108 fseek(fpfile, cm->current_video_frame * cm->MBs * sizeof(FIRSTPASS_MB_STATS),
110 ret = fread(fp_frame_stats->mb_stats, sizeof(FIRSTPASS_MB_STATS), cm->MBs,
119 static void output_mb_stats(FIRSTPASS_FRAME_MB_STATS *fp_frame_stats,
120 const VP9_COMMON *const cm) {
123 fpfile = fopen("firstpass_mb.stt", "a");
124 fwrite(fp_frame_stats->mb_stats, sizeof(FIRSTPASS_MB_STATS), cm->MBs, fpfile);
129 static int input_stats(TWO_PASS *p, FIRSTPASS_STATS *fps) {
130 if (p->stats_in >= p->stats_in_end)
138 static void output_stats(FIRSTPASS_STATS *stats,
139 struct vpx_codec_pkt_list *pktlist) {
140 struct vpx_codec_cx_pkt pkt;
141 pkt.kind = VPX_CODEC_STATS_PKT;
142 pkt.data.twopass_stats.buf = stats;
143 pkt.data.twopass_stats.sz = sizeof(FIRSTPASS_STATS);
144 vpx_codec_pkt_list_add(pktlist, &pkt);
150 fpfile = fopen("firstpass.stt", "a");
152 fprintf(fpfile, "%12.0f %12.0f %12.0f %12.0f %12.4f %12.4f"
153 "%12.4f %12.4f %12.4f %12.4f %12.4f %12.4f %12.4f"
154 "%12.0f %12.0f %12.4f %12.0f %12.0f %12.4f\n",
158 stats->sr_coded_error,
161 stats->pcnt_second_ref,
169 stats->mv_in_out_count,
178 static void zero_stats(FIRSTPASS_STATS *section) {
179 section->frame = 0.0;
180 section->intra_error = 0.0;
181 section->coded_error = 0.0;
182 section->sr_coded_error = 0.0;
183 section->pcnt_inter = 0.0;
184 section->pcnt_motion = 0.0;
185 section->pcnt_second_ref = 0.0;
186 section->pcnt_neutral = 0.0;
188 section->mvr_abs = 0.0;
190 section->mvc_abs = 0.0;
193 section->mv_in_out_count = 0.0;
194 section->new_mv_count = 0.0;
195 section->count = 0.0;
196 section->duration = 1.0;
197 section->spatial_layer_id = 0;
200 static void accumulate_stats(FIRSTPASS_STATS *section,
201 const FIRSTPASS_STATS *frame) {
202 section->frame += frame->frame;
203 section->spatial_layer_id = frame->spatial_layer_id;
204 section->intra_error += frame->intra_error;
205 section->coded_error += frame->coded_error;
206 section->sr_coded_error += frame->sr_coded_error;
207 section->pcnt_inter += frame->pcnt_inter;
208 section->pcnt_motion += frame->pcnt_motion;
209 section->pcnt_second_ref += frame->pcnt_second_ref;
210 section->pcnt_neutral += frame->pcnt_neutral;
211 section->MVr += frame->MVr;
212 section->mvr_abs += frame->mvr_abs;
213 section->MVc += frame->MVc;
214 section->mvc_abs += frame->mvc_abs;
215 section->MVrv += frame->MVrv;
216 section->MVcv += frame->MVcv;
217 section->mv_in_out_count += frame->mv_in_out_count;
218 section->new_mv_count += frame->new_mv_count;
219 section->count += frame->count;
220 section->duration += frame->duration;
223 static void subtract_stats(FIRSTPASS_STATS *section,
224 const FIRSTPASS_STATS *frame) {
225 section->frame -= frame->frame;
226 section->intra_error -= frame->intra_error;
227 section->coded_error -= frame->coded_error;
228 section->sr_coded_error -= frame->sr_coded_error;
229 section->pcnt_inter -= frame->pcnt_inter;
230 section->pcnt_motion -= frame->pcnt_motion;
231 section->pcnt_second_ref -= frame->pcnt_second_ref;
232 section->pcnt_neutral -= frame->pcnt_neutral;
233 section->MVr -= frame->MVr;
234 section->mvr_abs -= frame->mvr_abs;
235 section->MVc -= frame->MVc;
236 section->mvc_abs -= frame->mvc_abs;
237 section->MVrv -= frame->MVrv;
238 section->MVcv -= frame->MVcv;
239 section->mv_in_out_count -= frame->mv_in_out_count;
240 section->new_mv_count -= frame->new_mv_count;
241 section->count -= frame->count;
242 section->duration -= frame->duration;
245 static void avg_stats(FIRSTPASS_STATS *section) {
246 if (section->count < 1.0)
249 section->intra_error /= section->count;
250 section->coded_error /= section->count;
251 section->sr_coded_error /= section->count;
252 section->pcnt_inter /= section->count;
253 section->pcnt_second_ref /= section->count;
254 section->pcnt_neutral /= section->count;
255 section->pcnt_motion /= section->count;
256 section->MVr /= section->count;
257 section->mvr_abs /= section->count;
258 section->MVc /= section->count;
259 section->mvc_abs /= section->count;
260 section->MVrv /= section->count;
261 section->MVcv /= section->count;
262 section->mv_in_out_count /= section->count;
263 section->duration /= section->count;
266 // Calculate a modified Error used in distributing bits between easier and
268 static double calculate_modified_err(const TWO_PASS *twopass,
269 const VP9EncoderConfig *oxcf,
270 const FIRSTPASS_STATS *this_frame) {
271 const FIRSTPASS_STATS *const stats = &twopass->total_stats;
272 const double av_err = stats->coded_error / stats->count;
273 const double modified_error = av_err *
274 pow(this_frame->coded_error / DOUBLE_DIVIDE_CHECK(av_err),
275 oxcf->two_pass_vbrbias / 100.0);
276 return fclamp(modified_error,
277 twopass->modified_error_min, twopass->modified_error_max);
280 // This function returns the maximum target rate per frame.
281 static int frame_max_bits(const RATE_CONTROL *rc,
282 const VP9EncoderConfig *oxcf) {
283 int64_t max_bits = ((int64_t)rc->avg_frame_bandwidth *
284 (int64_t)oxcf->two_pass_vbrmax_section) / 100;
287 else if (max_bits > rc->max_frame_bandwidth)
288 max_bits = rc->max_frame_bandwidth;
290 return (int)max_bits;
293 void vp9_init_first_pass(VP9_COMP *cpi) {
294 zero_stats(&cpi->twopass.total_stats);
297 void vp9_end_first_pass(VP9_COMP *cpi) {
298 if (cpi->use_svc && cpi->svc.number_temporal_layers == 1) {
300 for (i = 0; i < cpi->svc.number_spatial_layers; ++i) {
301 output_stats(&cpi->svc.layer_context[i].twopass.total_stats,
302 cpi->output_pkt_list);
305 output_stats(&cpi->twopass.total_stats, cpi->output_pkt_list);
309 static vp9_variance_fn_t get_block_variance_fn(BLOCK_SIZE bsize) {
322 static unsigned int get_prediction_error(BLOCK_SIZE bsize,
323 const struct buf_2d *src,
324 const struct buf_2d *ref) {
326 const vp9_variance_fn_t fn = get_block_variance_fn(bsize);
327 fn(src->buf, src->stride, ref->buf, ref->stride, &sse);
331 // Refine the motion search range according to the frame dimension
332 // for first pass test.
333 static int get_search_range(const VP9_COMMON *cm) {
335 const int dim = MIN(cm->width, cm->height);
337 while ((dim << sr) < MAX_FULL_PEL_VAL)
342 static void first_pass_motion_search(VP9_COMP *cpi, MACROBLOCK *x,
343 const MV *ref_mv, MV *best_mv,
344 int *best_motion_err) {
345 MACROBLOCKD *const xd = &x->e_mbd;
347 MV ref_mv_full = {ref_mv->row >> 3, ref_mv->col >> 3};
348 int num00, tmp_err, n;
349 const BLOCK_SIZE bsize = xd->mi[0]->mbmi.sb_type;
350 vp9_variance_fn_ptr_t v_fn_ptr = cpi->fn_ptr[bsize];
351 const int new_mv_mode_penalty = 256;
354 int further_steps = (MAX_MVSEARCH_STEPS - 1) - step_param;
355 const int sr = get_search_range(&cpi->common);
359 // Override the default variance function to use MSE.
360 v_fn_ptr.vf = get_block_variance_fn(bsize);
362 // Center the initial step/diamond search on best mv.
363 tmp_err = cpi->diamond_search_sad(x, &cpi->ss_cfg, &ref_mv_full, &tmp_mv,
365 x->sadperbit16, &num00, &v_fn_ptr, ref_mv);
366 if (tmp_err < INT_MAX)
367 tmp_err = vp9_get_mvpred_var(x, &tmp_mv, ref_mv, &v_fn_ptr, 1);
368 if (tmp_err < INT_MAX - new_mv_mode_penalty)
369 tmp_err += new_mv_mode_penalty;
371 if (tmp_err < *best_motion_err) {
372 *best_motion_err = tmp_err;
376 // Carry out further step/diamond searches as necessary.
380 while (n < further_steps) {
386 tmp_err = cpi->diamond_search_sad(x, &cpi->ss_cfg, &ref_mv_full, &tmp_mv,
387 step_param + n, x->sadperbit16,
388 &num00, &v_fn_ptr, ref_mv);
389 if (tmp_err < INT_MAX)
390 tmp_err = vp9_get_mvpred_var(x, &tmp_mv, ref_mv, &v_fn_ptr, 1);
391 if (tmp_err < INT_MAX - new_mv_mode_penalty)
392 tmp_err += new_mv_mode_penalty;
394 if (tmp_err < *best_motion_err) {
395 *best_motion_err = tmp_err;
402 static BLOCK_SIZE get_bsize(const VP9_COMMON *cm, int mb_row, int mb_col) {
403 if (2 * mb_col + 1 < cm->mi_cols) {
404 return 2 * mb_row + 1 < cm->mi_rows ? BLOCK_16X16
407 return 2 * mb_row + 1 < cm->mi_rows ? BLOCK_8X16
412 static int find_fp_qindex() {
415 for (i = 0; i < QINDEX_RANGE; ++i)
416 if (vp9_convert_qindex_to_q(i) >= 30.0)
419 if (i == QINDEX_RANGE)
425 static void set_first_pass_params(VP9_COMP *cpi) {
426 VP9_COMMON *const cm = &cpi->common;
427 if (!cpi->refresh_alt_ref_frame &&
428 (cm->current_video_frame == 0 ||
429 (cpi->frame_flags & FRAMEFLAGS_KEY))) {
430 cm->frame_type = KEY_FRAME;
432 cm->frame_type = INTER_FRAME;
434 // Do not use periodic key frames.
435 cpi->rc.frames_to_key = INT_MAX;
438 void vp9_first_pass(VP9_COMP *cpi) {
440 MACROBLOCK *const x = &cpi->mb;
441 VP9_COMMON *const cm = &cpi->common;
442 MACROBLOCKD *const xd = &x->e_mbd;
444 struct macroblock_plane *const p = x->plane;
445 struct macroblockd_plane *const pd = xd->plane;
446 const PICK_MODE_CONTEXT *ctx = &cpi->pc_root->none;
449 int recon_yoffset, recon_uvoffset;
450 YV12_BUFFER_CONFIG *const lst_yv12 = get_ref_frame_buffer(cpi, LAST_FRAME);
451 YV12_BUFFER_CONFIG *gld_yv12 = get_ref_frame_buffer(cpi, GOLDEN_FRAME);
452 YV12_BUFFER_CONFIG *const new_yv12 = get_frame_new_buffer(cm);
453 int recon_y_stride = lst_yv12->y_stride;
454 int recon_uv_stride = lst_yv12->uv_stride;
455 int uv_mb_height = 16 >> (lst_yv12->y_height > lst_yv12->uv_height);
456 int64_t intra_error = 0;
457 int64_t coded_error = 0;
458 int64_t sr_coded_error = 0;
460 int sum_mvr = 0, sum_mvc = 0;
461 int sum_mvr_abs = 0, sum_mvc_abs = 0;
462 int64_t sum_mvrs = 0, sum_mvcs = 0;
465 int second_ref_count = 0;
466 int intrapenalty = 256;
467 int neutral_count = 0;
468 int new_mv_count = 0;
469 int sum_in_vectors = 0;
470 uint32_t lastmv_as_int = 0;
471 TWO_PASS *twopass = &cpi->twopass;
472 const MV zero_mv = {0, 0};
473 const YV12_BUFFER_CONFIG *first_ref_buf = lst_yv12;
475 #if CONFIG_FP_MB_STATS
476 FIRSTPASS_FRAME_MB_STATS *this_frame_mb_stats = &twopass->this_frame_mb_stats;
479 vp9_clear_system_state();
481 set_first_pass_params(cpi);
482 vp9_set_quantizer(cm, find_fp_qindex());
484 if (cpi->use_svc && cpi->svc.number_temporal_layers == 1) {
485 MV_REFERENCE_FRAME ref_frame = LAST_FRAME;
486 const YV12_BUFFER_CONFIG *scaled_ref_buf = NULL;
487 twopass = &cpi->svc.layer_context[cpi->svc.spatial_layer_id].twopass;
489 vp9_scale_references(cpi);
491 // Use either last frame or alt frame for motion search.
492 if (cpi->ref_frame_flags & VP9_LAST_FLAG) {
493 scaled_ref_buf = vp9_get_scaled_ref_frame(cpi, LAST_FRAME);
494 ref_frame = LAST_FRAME;
495 } else if (cpi->ref_frame_flags & VP9_ALT_FLAG) {
496 scaled_ref_buf = vp9_get_scaled_ref_frame(cpi, ALTREF_FRAME);
497 ref_frame = ALTREF_FRAME;
500 if (scaled_ref_buf != NULL) {
501 // Update the stride since we are using scaled reference buffer
502 first_ref_buf = scaled_ref_buf;
503 recon_y_stride = first_ref_buf->y_stride;
504 recon_uv_stride = first_ref_buf->uv_stride;
505 uv_mb_height = 16 >> (first_ref_buf->y_height > first_ref_buf->uv_height);
508 // Disable golden frame for svc first pass for now.
510 set_ref_ptrs(cm, xd, ref_frame, NONE);
512 cpi->Source = vp9_scale_if_required(cm, cpi->un_scaled_source,
513 &cpi->scaled_source);
516 vp9_setup_block_planes(&x->e_mbd, cm->subsampling_x, cm->subsampling_y);
518 vp9_setup_src_planes(x, cpi->Source, 0, 0);
519 vp9_setup_pre_planes(xd, 0, first_ref_buf, 0, 0, NULL);
520 vp9_setup_dst_planes(xd->plane, new_yv12, 0, 0);
522 xd->mi = cm->mi_grid_visible;
525 vp9_frame_init_quantizer(cpi);
527 for (i = 0; i < MAX_MB_PLANE; ++i) {
528 p[i].coeff = ctx->coeff_pbuf[i][1];
529 p[i].qcoeff = ctx->qcoeff_pbuf[i][1];
530 pd[i].dqcoeff = ctx->dqcoeff_pbuf[i][1];
531 p[i].eobs = ctx->eobs_pbuf[i][1];
535 vp9_init_mv_probs(cm);
536 vp9_initialize_rd_consts(cpi);
538 // Tiling is ignored in the first pass.
539 vp9_tile_init(&tile, cm, 0, 0);
541 for (mb_row = 0; mb_row < cm->mb_rows; ++mb_row) {
544 best_ref_mv.as_int = 0;
546 // Reset above block coeffs.
547 xd->up_available = (mb_row != 0);
548 recon_yoffset = (mb_row * recon_y_stride * 16);
549 recon_uvoffset = (mb_row * recon_uv_stride * uv_mb_height);
551 // Set up limit values for motion vectors to prevent them extending
552 // outside the UMV borders.
553 x->mv_row_min = -((mb_row * 16) + BORDER_MV_PIXELS_B16);
554 x->mv_row_max = ((cm->mb_rows - 1 - mb_row) * 16)
555 + BORDER_MV_PIXELS_B16;
557 for (mb_col = 0; mb_col < cm->mb_cols; ++mb_col) {
559 const int use_dc_pred = (mb_col || mb_row) && (!mb_col || !mb_row);
560 double error_weight = 1.0;
561 const BLOCK_SIZE bsize = get_bsize(cm, mb_row, mb_col);
563 vp9_clear_system_state();
565 xd->plane[0].dst.buf = new_yv12->y_buffer + recon_yoffset;
566 xd->plane[1].dst.buf = new_yv12->u_buffer + recon_uvoffset;
567 xd->plane[2].dst.buf = new_yv12->v_buffer + recon_uvoffset;
568 xd->left_available = (mb_col != 0);
569 xd->mi[0]->mbmi.sb_type = bsize;
570 xd->mi[0]->mbmi.ref_frame[0] = INTRA_FRAME;
571 set_mi_row_col(xd, &tile,
572 mb_row << 1, num_8x8_blocks_high_lookup[bsize],
573 mb_col << 1, num_8x8_blocks_wide_lookup[bsize],
574 cm->mi_rows, cm->mi_cols);
576 if (cpi->oxcf.aq_mode == VARIANCE_AQ) {
577 const int energy = vp9_block_energy(cpi, x, bsize);
578 error_weight = vp9_vaq_inv_q_ratio(energy);
581 // Do intra 16x16 prediction.
583 xd->mi[0]->mbmi.mode = DC_PRED;
584 xd->mi[0]->mbmi.tx_size = use_dc_pred ?
585 (bsize >= BLOCK_16X16 ? TX_16X16 : TX_8X8) : TX_4X4;
586 vp9_encode_intra_block_plane(x, bsize, 0);
587 this_error = vp9_get_mb_ss(x->plane[0].src_diff);
589 if (cpi->oxcf.aq_mode == VARIANCE_AQ) {
590 vp9_clear_system_state();
591 this_error = (int)(this_error * error_weight);
594 // Intrapenalty below deals with situations where the intra and inter
595 // error scores are very low (e.g. a plain black frame).
596 // We do not have special cases in first pass for 0,0 and nearest etc so
597 // all inter modes carry an overhead cost estimate for the mv.
598 // When the error score is very low this causes us to pick all or lots of
599 // INTRA modes and throw lots of key frames.
600 // This penalty adds a cost matching that of a 0,0 mv to the intra case.
601 this_error += intrapenalty;
603 // Accumulate the intra error.
604 intra_error += (int64_t)this_error;
606 #if CONFIG_FP_MB_STATS
607 if (cpi->use_fp_mb_stats) {
608 this_frame_mb_stats->mb_stats[mb_row * cm->mb_cols + mb_col].mode =
610 this_frame_mb_stats->mb_stats[mb_row * cm->mb_cols + mb_col].err =
612 this_frame_mb_stats->mb_stats[mb_row * cm->mb_cols + mb_col].mv.as_int
617 // Set up limit values for motion vectors to prevent them extending
618 // outside the UMV borders.
619 x->mv_col_min = -((mb_col * 16) + BORDER_MV_PIXELS_B16);
620 x->mv_col_max = ((cm->mb_cols - 1 - mb_col) * 16) + BORDER_MV_PIXELS_B16;
622 // Other than for the first frame do a motion search.
623 if (cm->current_video_frame > 0) {
624 int tmp_err, motion_error, raw_motion_error;
626 struct buf_2d unscaled_last_source_buf_2d;
628 xd->plane[0].pre[0].buf = first_ref_buf->y_buffer + recon_yoffset;
629 motion_error = get_prediction_error(bsize, &x->plane[0].src,
630 &xd->plane[0].pre[0]);
631 // Assume 0,0 motion with no mv overhead.
632 mv.as_int = tmp_mv.as_int = 0;
634 // Compute the motion error of the 0,0 motion using the last source
635 // frame as the reference. Skip the further motion search on
636 // reconstructed frame if this error is small.
637 unscaled_last_source_buf_2d.buf =
638 cpi->unscaled_last_source->y_buffer + recon_yoffset;
639 unscaled_last_source_buf_2d.stride =
640 cpi->unscaled_last_source->y_stride;
641 raw_motion_error = get_prediction_error(bsize, &x->plane[0].src,
642 &unscaled_last_source_buf_2d);
644 // TODO(pengchong): Replace the hard-coded threshold
645 if (raw_motion_error > 25 ||
646 (cpi->use_svc && cpi->svc.number_temporal_layers == 1)) {
647 // Test last reference frame using the previous best mv as the
648 // starting point (best reference) for the search.
649 first_pass_motion_search(cpi, x, &best_ref_mv.as_mv, &mv.as_mv,
651 if (cpi->oxcf.aq_mode == VARIANCE_AQ) {
652 vp9_clear_system_state();
653 motion_error = (int)(motion_error * error_weight);
656 // If the current best reference mv is not centered on 0,0 then do a
657 // 0,0 based search as well.
658 if (best_ref_mv.as_int) {
660 first_pass_motion_search(cpi, x, &zero_mv, &tmp_mv.as_mv, &tmp_err);
661 if (cpi->oxcf.aq_mode == VARIANCE_AQ) {
662 vp9_clear_system_state();
663 tmp_err = (int)(tmp_err * error_weight);
666 if (tmp_err < motion_error) {
667 motion_error = tmp_err;
668 mv.as_int = tmp_mv.as_int;
672 // Search in an older reference frame.
673 if (cm->current_video_frame > 1 && gld_yv12 != NULL) {
674 // Assume 0,0 motion with no mv overhead.
677 xd->plane[0].pre[0].buf = gld_yv12->y_buffer + recon_yoffset;
678 gf_motion_error = get_prediction_error(bsize, &x->plane[0].src,
679 &xd->plane[0].pre[0]);
681 first_pass_motion_search(cpi, x, &zero_mv, &tmp_mv.as_mv,
683 if (cpi->oxcf.aq_mode == VARIANCE_AQ) {
684 vp9_clear_system_state();
685 gf_motion_error = (int)(gf_motion_error * error_weight);
688 if (gf_motion_error < motion_error && gf_motion_error < this_error)
691 // Reset to last frame as reference buffer.
692 xd->plane[0].pre[0].buf = first_ref_buf->y_buffer + recon_yoffset;
693 xd->plane[1].pre[0].buf = first_ref_buf->u_buffer + recon_uvoffset;
694 xd->plane[2].pre[0].buf = first_ref_buf->v_buffer + recon_uvoffset;
696 // In accumulating a score for the older reference frame take the
697 // best of the motion predicted score and the intra coded error
698 // (just as will be done for) accumulation of "coded_error" for
700 if (gf_motion_error < this_error)
701 sr_coded_error += gf_motion_error;
703 sr_coded_error += this_error;
705 sr_coded_error += motion_error;
708 sr_coded_error += motion_error;
711 // Start by assuming that intra mode is best.
712 best_ref_mv.as_int = 0;
714 if (motion_error <= this_error) {
715 // Keep a count of cases where the inter and intra were very close
716 // and very low. This helps with scene cut detection for example in
717 // cropped clips with black bars at the sides or top and bottom.
718 if (((this_error - intrapenalty) * 9 <= motion_error * 10) &&
719 this_error < 2 * intrapenalty)
724 this_error = motion_error;
725 xd->mi[0]->mbmi.mode = NEWMV;
726 xd->mi[0]->mbmi.mv[0] = mv;
727 xd->mi[0]->mbmi.tx_size = TX_4X4;
728 xd->mi[0]->mbmi.ref_frame[0] = LAST_FRAME;
729 xd->mi[0]->mbmi.ref_frame[1] = NONE;
730 vp9_build_inter_predictors_sby(xd, mb_row << 1, mb_col << 1, bsize);
731 vp9_encode_sby_pass1(x, bsize);
732 sum_mvr += mv.as_mv.row;
733 sum_mvr_abs += abs(mv.as_mv.row);
734 sum_mvc += mv.as_mv.col;
735 sum_mvc_abs += abs(mv.as_mv.col);
736 sum_mvrs += mv.as_mv.row * mv.as_mv.row;
737 sum_mvcs += mv.as_mv.col * mv.as_mv.col;
740 best_ref_mv.as_int = mv.as_int;
742 #if CONFIG_FP_MB_STATS
743 if (cpi->use_fp_mb_stats) {
744 this_frame_mb_stats->mb_stats[mb_row * cm->mb_cols + mb_col].mode =
746 this_frame_mb_stats->mb_stats[mb_row * cm->mb_cols + mb_col].err =
748 this_frame_mb_stats->mb_stats[mb_row * cm->mb_cols + mb_col].mv.
756 // Non-zero vector, was it different from the last non zero vector?
757 if (mv.as_int != lastmv_as_int)
759 lastmv_as_int = mv.as_int;
761 // Does the row vector point inwards or outwards?
762 if (mb_row < cm->mb_rows / 2) {
763 if (mv.as_mv.row > 0)
765 else if (mv.as_mv.row < 0)
767 } else if (mb_row > cm->mb_rows / 2) {
768 if (mv.as_mv.row > 0)
770 else if (mv.as_mv.row < 0)
774 // Does the col vector point inwards or outwards?
775 if (mb_col < cm->mb_cols / 2) {
776 if (mv.as_mv.col > 0)
778 else if (mv.as_mv.col < 0)
780 } else if (mb_col > cm->mb_cols / 2) {
781 if (mv.as_mv.col > 0)
783 else if (mv.as_mv.col < 0)
789 sr_coded_error += (int64_t)this_error;
791 coded_error += (int64_t)this_error;
793 // Adjust to the next column of MBs.
794 x->plane[0].src.buf += 16;
795 x->plane[1].src.buf += uv_mb_height;
796 x->plane[2].src.buf += uv_mb_height;
799 recon_uvoffset += uv_mb_height;
802 // Adjust to the next row of MBs.
803 x->plane[0].src.buf += 16 * x->plane[0].src.stride - 16 * cm->mb_cols;
804 x->plane[1].src.buf += uv_mb_height * x->plane[1].src.stride -
805 uv_mb_height * cm->mb_cols;
806 x->plane[2].src.buf += uv_mb_height * x->plane[1].src.stride -
807 uv_mb_height * cm->mb_cols;
809 vp9_clear_system_state();
812 vp9_clear_system_state();
816 fps.frame = cm->current_video_frame;
817 fps.spatial_layer_id = cpi->svc.spatial_layer_id;
818 fps.intra_error = (double)(intra_error >> 8);
819 fps.coded_error = (double)(coded_error >> 8);
820 fps.sr_coded_error = (double)(sr_coded_error >> 8);
822 fps.pcnt_inter = (double)intercount / cm->MBs;
823 fps.pcnt_second_ref = (double)second_ref_count / cm->MBs;
824 fps.pcnt_neutral = (double)neutral_count / cm->MBs;
827 fps.MVr = (double)sum_mvr / mvcount;
828 fps.mvr_abs = (double)sum_mvr_abs / mvcount;
829 fps.MVc = (double)sum_mvc / mvcount;
830 fps.mvc_abs = (double)sum_mvc_abs / mvcount;
831 fps.MVrv = ((double)sum_mvrs - (fps.MVr * fps.MVr / mvcount)) / mvcount;
832 fps.MVcv = ((double)sum_mvcs - (fps.MVc * fps.MVc / mvcount)) / mvcount;
833 fps.mv_in_out_count = (double)sum_in_vectors / (mvcount * 2);
834 fps.new_mv_count = new_mv_count;
835 fps.pcnt_motion = (double)mvcount / cm->MBs;
843 fps.mv_in_out_count = 0.0;
844 fps.new_mv_count = 0.0;
845 fps.pcnt_motion = 0.0;
848 // TODO(paulwilkins): Handle the case when duration is set to 0, or
849 // something less than the full time between subsequent values of
850 // cpi->source_time_stamp.
851 fps.duration = (double)(cpi->source->ts_end - cpi->source->ts_start);
853 // Don't want to do output stats with a stack variable!
854 twopass->this_frame_stats = fps;
855 output_stats(&twopass->this_frame_stats, cpi->output_pkt_list);
856 accumulate_stats(&twopass->total_stats, &fps);
858 #if CONFIG_FP_MB_STATS
859 if (cpi->use_fp_mb_stats) {
860 output_mb_stats(this_frame_mb_stats, cm);
865 // Copy the previous Last Frame back into gf and and arf buffers if
866 // the prediction is good enough... but also don't allow it to lag too far.
867 if ((twopass->sr_update_lag > 3) ||
868 ((cm->current_video_frame > 0) &&
869 (twopass->this_frame_stats.pcnt_inter > 0.20) &&
870 ((twopass->this_frame_stats.intra_error /
871 DOUBLE_DIVIDE_CHECK(twopass->this_frame_stats.coded_error)) > 2.0))) {
872 if (gld_yv12 != NULL) {
873 vp8_yv12_copy_frame(lst_yv12, gld_yv12);
875 twopass->sr_update_lag = 1;
877 ++twopass->sr_update_lag;
880 vp9_extend_frame_borders(new_yv12);
882 if (cpi->use_svc && cpi->svc.number_temporal_layers == 1) {
883 vp9_update_reference_frames(cpi);
885 // Swap frame pointers so last frame refers to the frame we just compressed.
886 swap_yv12(lst_yv12, new_yv12);
889 // Special case for the first frame. Copy into the GF buffer as a second
891 if (cm->current_video_frame == 0 && gld_yv12 != NULL) {
892 vp8_yv12_copy_frame(lst_yv12, gld_yv12);
895 // Use this to see what the first pass reconstruction looks like.
899 snprintf(filename, sizeof(filename), "enc%04d.yuv",
900 (int)cm->current_video_frame);
902 if (cm->current_video_frame == 0)
903 recon_file = fopen(filename, "wb");
905 recon_file = fopen(filename, "ab");
907 (void)fwrite(lst_yv12->buffer_alloc, lst_yv12->frame_size, 1, recon_file);
911 ++cm->current_video_frame;
914 static double calc_correction_factor(double err_per_mb,
919 const double error_term = err_per_mb / err_divisor;
921 // Adjustment based on actual quantizer to power term.
922 const double power_term = MIN(vp9_convert_qindex_to_q(q) * 0.0125 + pt_low,
925 // Calculate correction factor.
926 if (power_term < 1.0)
927 assert(error_term >= 0.0);
929 return fclamp(pow(error_term, power_term), 0.05, 5.0);
932 static int get_twopass_worst_quality(const VP9_COMP *cpi,
933 const FIRSTPASS_STATS *stats,
934 int section_target_bandwidth) {
935 const RATE_CONTROL *const rc = &cpi->rc;
936 const VP9EncoderConfig *const oxcf = &cpi->oxcf;
938 if (section_target_bandwidth <= 0) {
939 return rc->worst_quality; // Highest value allowed
941 const int num_mbs = cpi->common.MBs;
942 const double section_err = stats->coded_error / stats->count;
943 const double err_per_mb = section_err / num_mbs;
944 const double speed_term = 1.0 + 0.04 * oxcf->speed;
945 const int target_norm_bits_per_mb = ((uint64_t)section_target_bandwidth <<
946 BPER_MB_NORMBITS) / num_mbs;
948 int is_svc_upper_layer = 0;
949 if (cpi->use_svc && cpi->svc.number_temporal_layers == 1 &&
950 cpi->svc.spatial_layer_id > 0) {
951 is_svc_upper_layer = 1;
954 // Try and pick a max Q that will be high enough to encode the
955 // content at the given rate.
956 for (q = rc->best_quality; q < rc->worst_quality; ++q) {
957 const double factor =
958 calc_correction_factor(err_per_mb, ERR_DIVISOR,
959 is_svc_upper_layer ? SVC_FACTOR_PT_LOW :
960 FACTOR_PT_LOW, FACTOR_PT_HIGH, q);
961 const int bits_per_mb = vp9_rc_bits_per_mb(INTER_FRAME, q,
962 factor * speed_term);
963 if (bits_per_mb <= target_norm_bits_per_mb)
967 // Restriction on active max q for constrained quality mode.
968 if (cpi->oxcf.rc_mode == VPX_CQ)
969 q = MAX(q, oxcf->cq_level);
974 extern void vp9_new_framerate(VP9_COMP *cpi, double framerate);
976 void vp9_init_second_pass(VP9_COMP *cpi) {
977 SVC *const svc = &cpi->svc;
978 const VP9EncoderConfig *const oxcf = &cpi->oxcf;
979 const int is_spatial_svc = (svc->number_spatial_layers > 1) &&
980 (svc->number_temporal_layers == 1);
981 TWO_PASS *const twopass = is_spatial_svc ?
982 &svc->layer_context[svc->spatial_layer_id].twopass : &cpi->twopass;
984 FIRSTPASS_STATS *stats;
986 zero_stats(&twopass->total_stats);
987 zero_stats(&twopass->total_left_stats);
989 if (!twopass->stats_in_end)
992 stats = &twopass->total_stats;
994 *stats = *twopass->stats_in_end;
995 twopass->total_left_stats = *stats;
997 frame_rate = 10000000.0 * stats->count / stats->duration;
998 // Each frame can have a different duration, as the frame rate in the source
999 // isn't guaranteed to be constant. The frame rate prior to the first frame
1000 // encoded in the second pass is a guess. However, the sum duration is not.
1001 // It is calculated based on the actual durations of all frames from the
1004 if (is_spatial_svc) {
1005 vp9_update_spatial_layer_framerate(cpi, frame_rate);
1006 twopass->bits_left = (int64_t)(stats->duration *
1007 svc->layer_context[svc->spatial_layer_id].target_bandwidth /
1010 vp9_new_framerate(cpi, frame_rate);
1011 twopass->bits_left = (int64_t)(stats->duration * oxcf->target_bandwidth /
1015 // Calculate a minimum intra value to be used in determining the IIratio
1016 // scores used in the second pass. We have this minimum to make sure
1017 // that clips that are static but "low complexity" in the intra domain
1018 // are still boosted appropriately for KF/GF/ARF.
1019 if (!is_spatial_svc) {
1020 // We don't know the number of MBs for each layer at this point.
1021 // So we will do it later.
1022 twopass->kf_intra_err_min = KF_MB_INTRA_MIN * cpi->common.MBs;
1023 twopass->gf_intra_err_min = GF_MB_INTRA_MIN * cpi->common.MBs;
1026 // This variable monitors how far behind the second ref update is lagging.
1027 twopass->sr_update_lag = 1;
1029 // Scan the first pass file and calculate a modified total error based upon
1030 // the bias/power function used to allocate bits.
1032 const double avg_error = stats->coded_error /
1033 DOUBLE_DIVIDE_CHECK(stats->count);
1034 const FIRSTPASS_STATS *s = twopass->stats_in;
1035 double modified_error_total = 0.0;
1036 twopass->modified_error_min = (avg_error *
1037 oxcf->two_pass_vbrmin_section) / 100;
1038 twopass->modified_error_max = (avg_error *
1039 oxcf->two_pass_vbrmax_section) / 100;
1040 while (s < twopass->stats_in_end) {
1041 modified_error_total += calculate_modified_err(twopass, oxcf, s);
1044 twopass->modified_error_left = modified_error_total;
1047 // Reset the vbr bits off target counter
1048 cpi->rc.vbr_bits_off_target = 0;
1051 // This function gives an estimate of how badly we believe the prediction
1052 // quality is decaying from frame to frame.
1053 static double get_prediction_decay_rate(const VP9_COMMON *cm,
1054 const FIRSTPASS_STATS *next_frame) {
1055 // Look at the observed drop in prediction quality between the last frame
1056 // and the GF buffer (which contains an older frame).
1057 const double mb_sr_err_diff = (next_frame->sr_coded_error -
1058 next_frame->coded_error) / cm->MBs;
1059 const double second_ref_decay = mb_sr_err_diff <= 512.0
1060 ? fclamp(pow(1.0 - (mb_sr_err_diff / 512.0), 0.5), 0.85, 1.0)
1063 return MIN(second_ref_decay, next_frame->pcnt_inter);
1066 // Function to test for a condition where a complex transition is followed
1067 // by a static section. For example in slide shows where there is a fade
1068 // between slides. This is to help with more optimal kf and gf positioning.
1069 static int detect_transition_to_still(TWO_PASS *twopass,
1070 int frame_interval, int still_interval,
1071 double loop_decay_rate,
1072 double last_decay_rate) {
1073 int trans_to_still = 0;
1075 // Break clause to detect very still sections after motion
1076 // For example a static image after a fade or other transition
1077 // instead of a clean scene cut.
1078 if (frame_interval > MIN_GF_INTERVAL &&
1079 loop_decay_rate >= 0.999 &&
1080 last_decay_rate < 0.9) {
1082 const FIRSTPASS_STATS *position = twopass->stats_in;
1083 FIRSTPASS_STATS tmp_next_frame;
1085 // Look ahead a few frames to see if static condition persists...
1086 for (j = 0; j < still_interval; ++j) {
1087 if (EOF == input_stats(twopass, &tmp_next_frame))
1090 if (tmp_next_frame.pcnt_inter - tmp_next_frame.pcnt_motion < 0.999)
1094 reset_fpf_position(twopass, position);
1096 // Only if it does do we signal a transition to still.
1097 if (j == still_interval)
1101 return trans_to_still;
1104 // This function detects a flash through the high relative pcnt_second_ref
1105 // score in the frame following a flash frame. The offset passed in should
1107 static int detect_flash(const TWO_PASS *twopass, int offset) {
1108 const FIRSTPASS_STATS *const next_frame = read_frame_stats(twopass, offset);
1110 // What we are looking for here is a situation where there is a
1111 // brief break in prediction (such as a flash) but subsequent frames
1112 // are reasonably well predicted by an earlier (pre flash) frame.
1113 // The recovery after a flash is indicated by a high pcnt_second_ref
1114 // compared to pcnt_inter.
1115 return next_frame != NULL &&
1116 next_frame->pcnt_second_ref > next_frame->pcnt_inter &&
1117 next_frame->pcnt_second_ref >= 0.5;
1120 // Update the motion related elements to the GF arf boost calculation.
1121 static void accumulate_frame_motion_stats(const FIRSTPASS_STATS *stats,
1123 double *mv_in_out_accumulator,
1124 double *abs_mv_in_out_accumulator,
1125 double *mv_ratio_accumulator) {
1126 const double pct = stats->pcnt_motion;
1128 // Accumulate Motion In/Out of frame stats.
1129 *mv_in_out = stats->mv_in_out_count * pct;
1130 *mv_in_out_accumulator += *mv_in_out;
1131 *abs_mv_in_out_accumulator += fabs(*mv_in_out);
1133 // Accumulate a measure of how uniform (or conversely how random) the motion
1134 // field is (a ratio of abs(mv) / mv).
1136 const double mvr_ratio = fabs(stats->mvr_abs) /
1137 DOUBLE_DIVIDE_CHECK(fabs(stats->MVr));
1138 const double mvc_ratio = fabs(stats->mvc_abs) /
1139 DOUBLE_DIVIDE_CHECK(fabs(stats->MVc));
1141 *mv_ratio_accumulator += pct * (mvr_ratio < stats->mvr_abs ?
1142 mvr_ratio : stats->mvr_abs);
1143 *mv_ratio_accumulator += pct * (mvc_ratio < stats->mvc_abs ?
1144 mvc_ratio : stats->mvc_abs);
1148 // Calculate a baseline boost number for the current frame.
1149 static double calc_frame_boost(const TWO_PASS *twopass,
1150 const FIRSTPASS_STATS *this_frame,
1151 double this_frame_mv_in_out) {
1154 // Underlying boost factor is based on inter intra error ratio.
1155 if (this_frame->intra_error > twopass->gf_intra_err_min)
1156 frame_boost = (IIFACTOR * this_frame->intra_error /
1157 DOUBLE_DIVIDE_CHECK(this_frame->coded_error));
1159 frame_boost = (IIFACTOR * twopass->gf_intra_err_min /
1160 DOUBLE_DIVIDE_CHECK(this_frame->coded_error));
1162 // Increase boost for frames where new data coming into frame (e.g. zoom out).
1163 // Slightly reduce boost if there is a net balance of motion out of the frame
1164 // (zoom in). The range for this_frame_mv_in_out is -1.0 to +1.0.
1165 if (this_frame_mv_in_out > 0.0)
1166 frame_boost += frame_boost * (this_frame_mv_in_out * 2.0);
1167 // In the extreme case the boost is halved.
1169 frame_boost += frame_boost * (this_frame_mv_in_out / 2.0);
1171 return MIN(frame_boost, GF_RMAX);
1174 static int calc_arf_boost(VP9_COMP *cpi, int offset,
1175 int f_frames, int b_frames,
1176 int *f_boost, int *b_boost) {
1177 TWO_PASS *const twopass = &cpi->twopass;
1179 double boost_score = 0.0;
1180 double mv_ratio_accumulator = 0.0;
1181 double decay_accumulator = 1.0;
1182 double this_frame_mv_in_out = 0.0;
1183 double mv_in_out_accumulator = 0.0;
1184 double abs_mv_in_out_accumulator = 0.0;
1186 int flash_detected = 0;
1188 // Search forward from the proposed arf/next gf position.
1189 for (i = 0; i < f_frames; ++i) {
1190 const FIRSTPASS_STATS *this_frame = read_frame_stats(twopass, i + offset);
1191 if (this_frame == NULL)
1194 // Update the motion related elements to the boost calculation.
1195 accumulate_frame_motion_stats(this_frame,
1196 &this_frame_mv_in_out, &mv_in_out_accumulator,
1197 &abs_mv_in_out_accumulator,
1198 &mv_ratio_accumulator);
1200 // We want to discount the flash frame itself and the recovery
1201 // frame that follows as both will have poor scores.
1202 flash_detected = detect_flash(twopass, i + offset) ||
1203 detect_flash(twopass, i + offset + 1);
1205 // Accumulate the effect of prediction quality decay.
1206 if (!flash_detected) {
1207 decay_accumulator *= get_prediction_decay_rate(&cpi->common, this_frame);
1208 decay_accumulator = decay_accumulator < MIN_DECAY_FACTOR
1209 ? MIN_DECAY_FACTOR : decay_accumulator;
1212 boost_score += decay_accumulator * calc_frame_boost(twopass, this_frame,
1213 this_frame_mv_in_out);
1216 *f_boost = (int)boost_score;
1218 // Reset for backward looking loop.
1220 mv_ratio_accumulator = 0.0;
1221 decay_accumulator = 1.0;
1222 this_frame_mv_in_out = 0.0;
1223 mv_in_out_accumulator = 0.0;
1224 abs_mv_in_out_accumulator = 0.0;
1226 // Search backward towards last gf position.
1227 for (i = -1; i >= -b_frames; --i) {
1228 const FIRSTPASS_STATS *this_frame = read_frame_stats(twopass, i + offset);
1229 if (this_frame == NULL)
1232 // Update the motion related elements to the boost calculation.
1233 accumulate_frame_motion_stats(this_frame,
1234 &this_frame_mv_in_out, &mv_in_out_accumulator,
1235 &abs_mv_in_out_accumulator,
1236 &mv_ratio_accumulator);
1238 // We want to discount the the flash frame itself and the recovery
1239 // frame that follows as both will have poor scores.
1240 flash_detected = detect_flash(twopass, i + offset) ||
1241 detect_flash(twopass, i + offset + 1);
1243 // Cumulative effect of prediction quality decay.
1244 if (!flash_detected) {
1245 decay_accumulator *= get_prediction_decay_rate(&cpi->common, this_frame);
1246 decay_accumulator = decay_accumulator < MIN_DECAY_FACTOR
1247 ? MIN_DECAY_FACTOR : decay_accumulator;
1250 boost_score += decay_accumulator * calc_frame_boost(twopass, this_frame,
1251 this_frame_mv_in_out);
1253 *b_boost = (int)boost_score;
1255 arf_boost = (*f_boost + *b_boost);
1256 if (arf_boost < ((b_frames + f_frames) * 20))
1257 arf_boost = ((b_frames + f_frames) * 20);
1262 // Calculate a section intra ratio used in setting max loop filter.
1263 static int calculate_section_intra_ratio(const FIRSTPASS_STATS *begin,
1264 const FIRSTPASS_STATS *end,
1265 int section_length) {
1266 const FIRSTPASS_STATS *s = begin;
1267 double intra_error = 0.0;
1268 double coded_error = 0.0;
1271 while (s < end && i < section_length) {
1272 intra_error += s->intra_error;
1273 coded_error += s->coded_error;
1278 return (int)(intra_error / DOUBLE_DIVIDE_CHECK(coded_error));
1281 // Calculate the total bits to allocate in this GF/ARF group.
1282 static int64_t calculate_total_gf_group_bits(VP9_COMP *cpi,
1283 double gf_group_err) {
1284 const RATE_CONTROL *const rc = &cpi->rc;
1285 const TWO_PASS *const twopass = &cpi->twopass;
1286 const int max_bits = frame_max_bits(rc, &cpi->oxcf);
1287 int64_t total_group_bits;
1289 // Calculate the bits to be allocated to the group as a whole.
1290 if ((twopass->kf_group_bits > 0) && (twopass->kf_group_error_left > 0)) {
1291 total_group_bits = (int64_t)(twopass->kf_group_bits *
1292 (gf_group_err / twopass->kf_group_error_left));
1294 total_group_bits = 0;
1297 // Clamp odd edge cases.
1298 total_group_bits = (total_group_bits < 0) ?
1299 0 : (total_group_bits > twopass->kf_group_bits) ?
1300 twopass->kf_group_bits : total_group_bits;
1302 // Clip based on user supplied data rate variability limit.
1303 if (total_group_bits > (int64_t)max_bits * rc->baseline_gf_interval)
1304 total_group_bits = (int64_t)max_bits * rc->baseline_gf_interval;
1306 return total_group_bits;
1309 // Calculate the number bits extra to assign to boosted frames in a group.
1310 static int calculate_boost_bits(int frame_count,
1311 int boost, int64_t total_group_bits) {
1312 int allocation_chunks;
1314 // return 0 for invalid inputs (could arise e.g. through rounding errors)
1315 if (!boost || (total_group_bits <= 0) || (frame_count <= 0) )
1318 allocation_chunks = (frame_count * 100) + boost;
1320 // Prevent overflow.
1322 int divisor = boost >> 10;
1324 allocation_chunks /= divisor;
1327 // Calculate the number of extra bits for use in the boosted frame or frames.
1328 return MAX((int)(((int64_t)boost * total_group_bits) / allocation_chunks), 0);
1331 // Current limit on maximum number of active arfs in a GF/ARF group.
1332 #define MAX_ACTIVE_ARFS 2
1335 // This function indirects the choice of buffers for arfs.
1336 // At the moment the values are fixed but this may change as part of
1337 // the integration process with other codec features that swap buffers around.
1338 static void get_arf_buffer_indices(unsigned char *arf_buffer_indices) {
1339 arf_buffer_indices[0] = ARF_SLOT1;
1340 arf_buffer_indices[1] = ARF_SLOT2;
1343 static void allocate_gf_group_bits(VP9_COMP *cpi, int64_t gf_group_bits,
1344 double group_error, int gf_arf_bits) {
1345 RATE_CONTROL *const rc = &cpi->rc;
1346 const VP9EncoderConfig *const oxcf = &cpi->oxcf;
1347 TWO_PASS *twopass = &cpi->twopass;
1348 FIRSTPASS_STATS frame_stats;
1350 int frame_index = 1;
1351 int target_frame_size;
1353 const int max_bits = frame_max_bits(&cpi->rc, &cpi->oxcf);
1354 int64_t total_group_bits = gf_group_bits;
1355 double modified_err = 0.0;
1356 double err_fraction;
1357 int mid_boost_bits = 0;
1359 unsigned char arf_buffer_indices[MAX_ACTIVE_ARFS];
1361 key_frame = cpi->common.frame_type == KEY_FRAME ||
1362 vp9_is_upper_layer_key_frame(cpi);
1364 get_arf_buffer_indices(arf_buffer_indices);
1366 // For key frames the frame target rate is already set and it
1367 // is also the golden frame.
1369 if (rc->source_alt_ref_active) {
1370 twopass->gf_group.update_type[0] = OVERLAY_UPDATE;
1371 twopass->gf_group.rf_level[0] = INTER_NORMAL;
1372 twopass->gf_group.bit_allocation[0] = 0;
1373 twopass->gf_group.arf_update_idx[0] = arf_buffer_indices[0];
1374 twopass->gf_group.arf_ref_idx[0] = arf_buffer_indices[0];
1376 twopass->gf_group.update_type[0] = GF_UPDATE;
1377 twopass->gf_group.rf_level[0] = GF_ARF_STD;
1378 twopass->gf_group.bit_allocation[0] = gf_arf_bits;
1379 twopass->gf_group.arf_update_idx[0] = arf_buffer_indices[0];
1380 twopass->gf_group.arf_ref_idx[0] = arf_buffer_indices[0];
1383 // Step over the golden frame / overlay frame
1384 if (EOF == input_stats(twopass, &frame_stats))
1388 // Deduct the boost bits for arf (or gf if it is not a key frame)
1389 // from the group total.
1390 if (rc->source_alt_ref_pending || !key_frame)
1391 total_group_bits -= gf_arf_bits;
1393 // Store the bits to spend on the ARF if there is one.
1394 if (rc->source_alt_ref_pending) {
1395 if (cpi->multi_arf_enabled) {
1396 // A portion of the gf / arf extra bits are set asside for lower level
1397 // boosted frames in the middle of the group.
1398 mid_boost_bits += gf_arf_bits >> 5;
1399 gf_arf_bits -= (gf_arf_bits >> 5);
1402 twopass->gf_group.update_type[frame_index] = ARF_UPDATE;
1403 twopass->gf_group.rf_level[frame_index] = GF_ARF_STD;
1404 twopass->gf_group.bit_allocation[frame_index] = gf_arf_bits;
1405 twopass->gf_group.arf_src_offset[frame_index] =
1406 (unsigned char)(rc->baseline_gf_interval - 1);
1407 twopass->gf_group.arf_update_idx[frame_index] = arf_buffer_indices[0];
1408 twopass->gf_group.arf_ref_idx[frame_index] =
1409 arf_buffer_indices[cpi->multi_arf_enabled && rc->source_alt_ref_active];
1412 if (cpi->multi_arf_enabled) {
1413 // Set aside a slot for a level 1 arf.
1414 twopass->gf_group.update_type[frame_index] = ARF_UPDATE;
1415 twopass->gf_group.rf_level[frame_index] = GF_ARF_LOW;
1416 twopass->gf_group.arf_src_offset[frame_index] =
1417 (unsigned char)((rc->baseline_gf_interval >> 1) - 1);
1418 twopass->gf_group.arf_update_idx[frame_index] = arf_buffer_indices[1];
1419 twopass->gf_group.arf_ref_idx[frame_index] = arf_buffer_indices[0];
1424 // Define middle frame
1425 mid_frame_idx = frame_index + (rc->baseline_gf_interval >> 1) - 1;
1427 // Allocate bits to the other frames in the group.
1428 for (i = 0; i < rc->baseline_gf_interval - 1; ++i) {
1430 if (EOF == input_stats(twopass, &frame_stats))
1433 modified_err = calculate_modified_err(twopass, oxcf, &frame_stats);
1435 if (group_error > 0)
1436 err_fraction = modified_err / DOUBLE_DIVIDE_CHECK(group_error);
1440 target_frame_size = (int)((double)total_group_bits * err_fraction);
1442 if (rc->source_alt_ref_pending && cpi->multi_arf_enabled) {
1443 mid_boost_bits += (target_frame_size >> 4);
1444 target_frame_size -= (target_frame_size >> 4);
1446 if (frame_index <= mid_frame_idx)
1449 twopass->gf_group.arf_update_idx[frame_index] = arf_buffer_indices[arf_idx];
1450 twopass->gf_group.arf_ref_idx[frame_index] = arf_buffer_indices[arf_idx];
1452 target_frame_size = clamp(target_frame_size, 0,
1453 MIN(max_bits, (int)total_group_bits));
1455 twopass->gf_group.update_type[frame_index] = LF_UPDATE;
1456 twopass->gf_group.rf_level[frame_index] = INTER_NORMAL;
1458 twopass->gf_group.bit_allocation[frame_index] = target_frame_size;
1463 // We need to configure the frame at the end of the sequence + 1 that will be
1464 // the start frame for the next group. Otherwise prior to the call to
1465 // vp9_rc_get_second_pass_params() the data will be undefined.
1466 twopass->gf_group.arf_update_idx[frame_index] = arf_buffer_indices[0];
1467 twopass->gf_group.arf_ref_idx[frame_index] = arf_buffer_indices[0];
1469 if (rc->source_alt_ref_pending) {
1470 twopass->gf_group.update_type[frame_index] = OVERLAY_UPDATE;
1471 twopass->gf_group.rf_level[frame_index] = INTER_NORMAL;
1473 // Final setup for second arf and its overlay.
1474 if (cpi->multi_arf_enabled) {
1475 twopass->gf_group.bit_allocation[2] =
1476 twopass->gf_group.bit_allocation[mid_frame_idx] + mid_boost_bits;
1477 twopass->gf_group.update_type[mid_frame_idx] = OVERLAY_UPDATE;
1478 twopass->gf_group.bit_allocation[mid_frame_idx] = 0;
1481 twopass->gf_group.update_type[frame_index] = GF_UPDATE;
1482 twopass->gf_group.rf_level[frame_index] = GF_ARF_STD;
1486 // Analyse and define a gf/arf group.
1487 static void define_gf_group(VP9_COMP *cpi, FIRSTPASS_STATS *this_frame) {
1488 RATE_CONTROL *const rc = &cpi->rc;
1489 const VP9EncoderConfig *const oxcf = &cpi->oxcf;
1490 TWO_PASS *const twopass = &cpi->twopass;
1491 FIRSTPASS_STATS next_frame;
1492 const FIRSTPASS_STATS *const start_pos = twopass->stats_in;
1495 double boost_score = 0.0;
1496 double old_boost_score = 0.0;
1497 double gf_group_err = 0.0;
1498 double gf_first_frame_err = 0.0;
1499 double mod_frame_err = 0.0;
1501 double mv_ratio_accumulator = 0.0;
1502 double decay_accumulator = 1.0;
1503 double zero_motion_accumulator = 1.0;
1505 double loop_decay_rate = 1.00;
1506 double last_loop_decay_rate = 1.00;
1508 double this_frame_mv_in_out = 0.0;
1509 double mv_in_out_accumulator = 0.0;
1510 double abs_mv_in_out_accumulator = 0.0;
1511 double mv_ratio_accumulator_thresh;
1512 unsigned int allow_alt_ref = is_altref_enabled(oxcf);
1517 int active_max_gf_interval;
1518 int64_t gf_group_bits;
1519 double gf_group_error_left;
1522 // Reset the GF group data structures unless this is a key
1523 // frame in which case it will already have been done.
1524 if (cpi->common.frame_type != KEY_FRAME) {
1525 vp9_zero(twopass->gf_group);
1528 vp9_clear_system_state();
1529 vp9_zero(next_frame);
1533 // Load stats for the current frame.
1534 mod_frame_err = calculate_modified_err(twopass, oxcf, this_frame);
1536 // Note the error of the frame at the start of the group. This will be
1537 // the GF frame error if we code a normal gf.
1538 gf_first_frame_err = mod_frame_err;
1540 // If this is a key frame or the overlay from a previous arf then
1541 // the error score / cost of this frame has already been accounted for.
1542 if (cpi->common.frame_type == KEY_FRAME || rc->source_alt_ref_active)
1543 gf_group_err -= gf_first_frame_err;
1545 // Motion breakout threshold for loop below depends on image size.
1546 mv_ratio_accumulator_thresh = (cpi->common.width + cpi->common.height) / 10.0;
1548 // Work out a maximum interval for the GF.
1549 // If the image appears completely static we can extend beyond this.
1550 // The value chosen depends on the active Q range. At low Q we have
1551 // bits to spare and are better with a smaller interval and smaller boost.
1552 // At high Q when there are few bits to spare we are better with a longer
1553 // interval to spread the cost of the GF.
1555 active_max_gf_interval =
1556 12 + ((int)vp9_convert_qindex_to_q(rc->last_q[INTER_FRAME]) >> 5);
1558 if (active_max_gf_interval > rc->max_gf_interval)
1559 active_max_gf_interval = rc->max_gf_interval;
1562 while (i < rc->static_scene_max_gf_interval && i < rc->frames_to_key) {
1565 // Accumulate error score of frames in this gf group.
1566 mod_frame_err = calculate_modified_err(twopass, oxcf, this_frame);
1567 gf_group_err += mod_frame_err;
1569 if (EOF == input_stats(twopass, &next_frame))
1572 // Test for the case where there is a brief flash but the prediction
1573 // quality back to an earlier frame is then restored.
1574 flash_detected = detect_flash(twopass, 0);
1576 // Update the motion related elements to the boost calculation.
1577 accumulate_frame_motion_stats(&next_frame,
1578 &this_frame_mv_in_out, &mv_in_out_accumulator,
1579 &abs_mv_in_out_accumulator,
1580 &mv_ratio_accumulator);
1582 // Accumulate the effect of prediction quality decay.
1583 if (!flash_detected) {
1584 last_loop_decay_rate = loop_decay_rate;
1585 loop_decay_rate = get_prediction_decay_rate(&cpi->common, &next_frame);
1586 decay_accumulator = decay_accumulator * loop_decay_rate;
1588 // Monitor for static sections.
1589 if ((next_frame.pcnt_inter - next_frame.pcnt_motion) <
1590 zero_motion_accumulator) {
1591 zero_motion_accumulator = next_frame.pcnt_inter -
1592 next_frame.pcnt_motion;
1595 // Break clause to detect very still sections after motion. For example,
1596 // a static image after a fade or other transition.
1597 if (detect_transition_to_still(twopass, i, 5, loop_decay_rate,
1598 last_loop_decay_rate)) {
1604 // Calculate a boost number for this frame.
1605 boost_score += decay_accumulator * calc_frame_boost(twopass, &next_frame,
1606 this_frame_mv_in_out);
1608 // Break out conditions.
1610 // Break at active_max_gf_interval unless almost totally static.
1611 (i >= active_max_gf_interval && (zero_motion_accumulator < 0.995)) ||
1613 // Don't break out with a very short interval.
1614 (i > MIN_GF_INTERVAL) &&
1615 ((boost_score > 125.0) || (next_frame.pcnt_inter < 0.75)) &&
1616 (!flash_detected) &&
1617 ((mv_ratio_accumulator > mv_ratio_accumulator_thresh) ||
1618 (abs_mv_in_out_accumulator > 3.0) ||
1619 (mv_in_out_accumulator < -2.0) ||
1620 ((boost_score - old_boost_score) < IIFACTOR)))) {
1621 boost_score = old_boost_score;
1625 *this_frame = next_frame;
1627 old_boost_score = boost_score;
1630 twopass->gf_zeromotion_pct = (int)(zero_motion_accumulator * 1000.0);
1632 // Don't allow a gf too near the next kf.
1633 if ((rc->frames_to_key - i) < MIN_GF_INTERVAL) {
1634 while (i < (rc->frames_to_key + !rc->next_key_frame_forced)) {
1637 if (EOF == input_stats(twopass, this_frame))
1640 if (i < rc->frames_to_key) {
1641 mod_frame_err = calculate_modified_err(twopass, oxcf, this_frame);
1642 gf_group_err += mod_frame_err;
1647 // Set the interval until the next gf.
1648 if (cpi->common.frame_type == KEY_FRAME || rc->source_alt_ref_active)
1649 rc->baseline_gf_interval = i - 1;
1651 rc->baseline_gf_interval = i;
1653 rc->frames_till_gf_update_due = rc->baseline_gf_interval;
1655 // Should we use the alternate reference frame.
1656 if (allow_alt_ref &&
1657 (i < cpi->oxcf.lag_in_frames) &&
1658 (i >= MIN_GF_INTERVAL) &&
1659 // For real scene cuts (not forced kfs) don't allow arf very near kf.
1660 (rc->next_key_frame_forced ||
1661 (i <= (rc->frames_to_key - MIN_GF_INTERVAL)))) {
1662 // Calculate the boost for alt ref.
1663 rc->gfu_boost = calc_arf_boost(cpi, 0, (i - 1), (i - 1), &f_boost,
1665 rc->source_alt_ref_pending = 1;
1668 rc->gfu_boost = (int)boost_score;
1669 rc->source_alt_ref_pending = 0;
1672 // Reset the file position.
1673 reset_fpf_position(twopass, start_pos);
1675 // Calculate the bits to be allocated to the gf/arf group as a whole
1676 gf_group_bits = calculate_total_gf_group_bits(cpi, gf_group_err);
1678 // Calculate the extra bits to be used for boosted frame(s)
1680 int q = rc->last_q[INTER_FRAME];
1681 int boost = (rc->gfu_boost * gfboost_qadjust(q)) / 100;
1683 // Set max and minimum boost and hence minimum allocation.
1684 boost = clamp(boost, 125, (rc->baseline_gf_interval + 1) * 200);
1686 // Calculate the extra bits to be used for boosted frame(s)
1687 gf_arf_bits = calculate_boost_bits(rc->baseline_gf_interval,
1688 boost, gf_group_bits);
1691 // Adjust KF group bits and error remaining.
1692 twopass->kf_group_error_left -= (int64_t)gf_group_err;
1694 // If this is an arf update we want to remove the score for the overlay
1695 // frame at the end which will usually be very cheap to code.
1696 // The overlay frame has already, in effect, been coded so we want to spread
1697 // the remaining bits among the other frames.
1698 // For normal GFs remove the score for the GF itself unless this is
1699 // also a key frame in which case it has already been accounted for.
1700 if (rc->source_alt_ref_pending) {
1701 gf_group_error_left = gf_group_err - mod_frame_err;
1702 } else if (cpi->common.frame_type != KEY_FRAME) {
1703 gf_group_error_left = gf_group_err - gf_first_frame_err;
1705 gf_group_error_left = gf_group_err;
1708 // Allocate bits to each of the frames in the GF group.
1709 allocate_gf_group_bits(cpi, gf_group_bits, gf_group_error_left, gf_arf_bits);
1711 // Reset the file position.
1712 reset_fpf_position(twopass, start_pos);
1714 // Calculate a section intra ratio used in setting max loop filter.
1715 if (cpi->common.frame_type != KEY_FRAME) {
1716 twopass->section_intra_rating =
1717 calculate_section_intra_ratio(start_pos, twopass->stats_in_end,
1718 rc->baseline_gf_interval);
1722 static int test_candidate_kf(TWO_PASS *twopass,
1723 const FIRSTPASS_STATS *last_frame,
1724 const FIRSTPASS_STATS *this_frame,
1725 const FIRSTPASS_STATS *next_frame) {
1726 int is_viable_kf = 0;
1728 // Does the frame satisfy the primary criteria of a key frame?
1729 // If so, then examine how well it predicts subsequent frames.
1730 if ((this_frame->pcnt_second_ref < 0.10) &&
1731 (next_frame->pcnt_second_ref < 0.10) &&
1732 ((this_frame->pcnt_inter < 0.05) ||
1733 (((this_frame->pcnt_inter - this_frame->pcnt_neutral) < 0.35) &&
1734 ((this_frame->intra_error /
1735 DOUBLE_DIVIDE_CHECK(this_frame->coded_error)) < 2.5) &&
1736 ((fabs(last_frame->coded_error - this_frame->coded_error) /
1737 DOUBLE_DIVIDE_CHECK(this_frame->coded_error) > 0.40) ||
1738 (fabs(last_frame->intra_error - this_frame->intra_error) /
1739 DOUBLE_DIVIDE_CHECK(this_frame->intra_error) > 0.40) ||
1740 ((next_frame->intra_error /
1741 DOUBLE_DIVIDE_CHECK(next_frame->coded_error)) > 3.5))))) {
1743 const FIRSTPASS_STATS *start_pos = twopass->stats_in;
1744 FIRSTPASS_STATS local_next_frame = *next_frame;
1745 double boost_score = 0.0;
1746 double old_boost_score = 0.0;
1747 double decay_accumulator = 1.0;
1749 // Examine how well the key frame predicts subsequent frames.
1750 for (i = 0; i < 16; ++i) {
1751 double next_iiratio = (IIKFACTOR1 * local_next_frame.intra_error /
1752 DOUBLE_DIVIDE_CHECK(local_next_frame.coded_error));
1754 if (next_iiratio > RMAX)
1755 next_iiratio = RMAX;
1757 // Cumulative effect of decay in prediction quality.
1758 if (local_next_frame.pcnt_inter > 0.85)
1759 decay_accumulator *= local_next_frame.pcnt_inter;
1761 decay_accumulator *= (0.85 + local_next_frame.pcnt_inter) / 2.0;
1763 // Keep a running total.
1764 boost_score += (decay_accumulator * next_iiratio);
1766 // Test various breakout clauses.
1767 if ((local_next_frame.pcnt_inter < 0.05) ||
1768 (next_iiratio < 1.5) ||
1769 (((local_next_frame.pcnt_inter -
1770 local_next_frame.pcnt_neutral) < 0.20) &&
1771 (next_iiratio < 3.0)) ||
1772 ((boost_score - old_boost_score) < 3.0) ||
1773 (local_next_frame.intra_error < 200)) {
1777 old_boost_score = boost_score;
1779 // Get the next frame details
1780 if (EOF == input_stats(twopass, &local_next_frame))
1784 // If there is tolerable prediction for at least the next 3 frames then
1785 // break out else discard this potential key frame and move on
1786 if (boost_score > 30.0 && (i > 3)) {
1789 // Reset the file position
1790 reset_fpf_position(twopass, start_pos);
1796 return is_viable_kf;
1799 static void find_next_key_frame(VP9_COMP *cpi, FIRSTPASS_STATS *this_frame) {
1801 RATE_CONTROL *const rc = &cpi->rc;
1802 TWO_PASS *const twopass = &cpi->twopass;
1803 const VP9EncoderConfig *const oxcf = &cpi->oxcf;
1804 const FIRSTPASS_STATS first_frame = *this_frame;
1805 const FIRSTPASS_STATS *const start_position = twopass->stats_in;
1806 FIRSTPASS_STATS next_frame;
1807 FIRSTPASS_STATS last_frame;
1809 double decay_accumulator = 1.0;
1810 double zero_motion_accumulator = 1.0;
1811 double boost_score = 0.0;
1812 double kf_mod_err = 0.0;
1813 double kf_group_err = 0.0;
1814 double recent_loop_decay[8] = {1.0, 1.0, 1.0, 1.0, 1.0, 1.0, 1.0, 1.0};
1816 vp9_zero(next_frame);
1818 cpi->common.frame_type = KEY_FRAME;
1820 // Reset the GF group data structures.
1821 vp9_zero(twopass->gf_group);
1823 // Is this a forced key frame by interval.
1824 rc->this_key_frame_forced = rc->next_key_frame_forced;
1826 // Clear the alt ref active flag as this can never be active on a key frame.
1827 rc->source_alt_ref_active = 0;
1829 // KF is always a GF so clear frames till next gf counter.
1830 rc->frames_till_gf_update_due = 0;
1832 rc->frames_to_key = 1;
1834 twopass->kf_group_bits = 0; // Total bits available to kf group
1835 twopass->kf_group_error_left = 0; // Group modified error score.
1837 kf_mod_err = calculate_modified_err(twopass, oxcf, this_frame);
1839 // Find the next keyframe.
1841 while (twopass->stats_in < twopass->stats_in_end &&
1842 rc->frames_to_key < cpi->oxcf.key_freq) {
1843 // Accumulate kf group error.
1844 kf_group_err += calculate_modified_err(twopass, oxcf, this_frame);
1846 // Load the next frame's stats.
1847 last_frame = *this_frame;
1848 input_stats(twopass, this_frame);
1850 // Provided that we are not at the end of the file...
1851 if (cpi->oxcf.auto_key &&
1852 lookup_next_frame_stats(twopass, &next_frame) != EOF) {
1853 double loop_decay_rate;
1855 // Check for a scene cut.
1856 if (test_candidate_kf(twopass, &last_frame, this_frame, &next_frame))
1859 // How fast is the prediction quality decaying?
1860 loop_decay_rate = get_prediction_decay_rate(&cpi->common, &next_frame);
1862 // We want to know something about the recent past... rather than
1863 // as used elsewhere where we are concerned with decay in prediction
1864 // quality since the last GF or KF.
1865 recent_loop_decay[i % 8] = loop_decay_rate;
1866 decay_accumulator = 1.0;
1867 for (j = 0; j < 8; ++j)
1868 decay_accumulator *= recent_loop_decay[j];
1870 // Special check for transition or high motion followed by a
1872 if (detect_transition_to_still(twopass, i, cpi->oxcf.key_freq - i,
1873 loop_decay_rate, decay_accumulator))
1876 // Step on to the next frame.
1877 ++rc->frames_to_key;
1879 // If we don't have a real key frame within the next two
1880 // key_freq intervals then break out of the loop.
1881 if (rc->frames_to_key >= 2 * cpi->oxcf.key_freq)
1884 ++rc->frames_to_key;
1889 // If there is a max kf interval set by the user we must obey it.
1890 // We already breakout of the loop above at 2x max.
1891 // This code centers the extra kf if the actual natural interval
1892 // is between 1x and 2x.
1893 if (cpi->oxcf.auto_key &&
1894 rc->frames_to_key > cpi->oxcf.key_freq) {
1895 FIRSTPASS_STATS tmp_frame = first_frame;
1897 rc->frames_to_key /= 2;
1899 // Reset to the start of the group.
1900 reset_fpf_position(twopass, start_position);
1904 // Rescan to get the correct error data for the forced kf group.
1905 for (i = 0; i < rc->frames_to_key; ++i) {
1906 kf_group_err += calculate_modified_err(twopass, oxcf, &tmp_frame);
1907 input_stats(twopass, &tmp_frame);
1909 rc->next_key_frame_forced = 1;
1910 } else if (twopass->stats_in == twopass->stats_in_end ||
1911 rc->frames_to_key >= cpi->oxcf.key_freq) {
1912 rc->next_key_frame_forced = 1;
1914 rc->next_key_frame_forced = 0;
1917 // Special case for the last key frame of the file.
1918 if (twopass->stats_in >= twopass->stats_in_end) {
1919 // Accumulate kf group error.
1920 kf_group_err += calculate_modified_err(twopass, oxcf, this_frame);
1923 // Calculate the number of bits that should be assigned to the kf group.
1924 if (twopass->bits_left > 0 && twopass->modified_error_left > 0.0) {
1925 // Maximum number of bits for a single normal frame (not key frame).
1926 const int max_bits = frame_max_bits(rc, &cpi->oxcf);
1928 // Maximum number of bits allocated to the key frame group.
1929 int64_t max_grp_bits;
1931 // Default allocation based on bits left and relative
1932 // complexity of the section.
1933 twopass->kf_group_bits = (int64_t)(twopass->bits_left *
1934 (kf_group_err / twopass->modified_error_left));
1936 // Clip based on maximum per frame rate defined by the user.
1937 max_grp_bits = (int64_t)max_bits * (int64_t)rc->frames_to_key;
1938 if (twopass->kf_group_bits > max_grp_bits)
1939 twopass->kf_group_bits = max_grp_bits;
1941 twopass->kf_group_bits = 0;
1943 twopass->kf_group_bits = MAX(0, twopass->kf_group_bits);
1945 // Reset the first pass file position.
1946 reset_fpf_position(twopass, start_position);
1948 // Scan through the kf group collating various stats used to deteermine
1949 // how many bits to spend on it.
1950 decay_accumulator = 1.0;
1952 for (i = 0; i < rc->frames_to_key; ++i) {
1953 if (EOF == input_stats(twopass, &next_frame))
1956 // Monitor for static sections.
1957 if ((next_frame.pcnt_inter - next_frame.pcnt_motion) <
1958 zero_motion_accumulator) {
1959 zero_motion_accumulator = (next_frame.pcnt_inter -
1960 next_frame.pcnt_motion);
1963 // For the first few frames collect data to decide kf boost.
1964 if (i <= (rc->max_gf_interval * 2)) {
1966 if (next_frame.intra_error > twopass->kf_intra_err_min)
1967 r = (IIKFACTOR2 * next_frame.intra_error /
1968 DOUBLE_DIVIDE_CHECK(next_frame.coded_error));
1970 r = (IIKFACTOR2 * twopass->kf_intra_err_min /
1971 DOUBLE_DIVIDE_CHECK(next_frame.coded_error));
1976 // How fast is prediction quality decaying.
1977 if (!detect_flash(twopass, 0)) {
1978 const double loop_decay_rate = get_prediction_decay_rate(&cpi->common,
1980 decay_accumulator *= loop_decay_rate;
1981 decay_accumulator = MAX(decay_accumulator, MIN_DECAY_FACTOR);
1984 boost_score += (decay_accumulator * r);
1988 reset_fpf_position(twopass, start_position);
1990 // Store the zero motion percentage
1991 twopass->kf_zeromotion_pct = (int)(zero_motion_accumulator * 100.0);
1993 // Calculate a section intra ratio used in setting max loop filter.
1994 twopass->section_intra_rating =
1995 calculate_section_intra_ratio(start_position, twopass->stats_in_end,
1998 // Work out how many bits to allocate for the key frame itself.
1999 rc->kf_boost = (int)boost_score;
2001 if (rc->kf_boost < (rc->frames_to_key * 3))
2002 rc->kf_boost = (rc->frames_to_key * 3);
2003 if (rc->kf_boost < MIN_KF_BOOST)
2004 rc->kf_boost = MIN_KF_BOOST;
2006 kf_bits = calculate_boost_bits((rc->frames_to_key - 1),
2007 rc->kf_boost, twopass->kf_group_bits);
2009 twopass->kf_group_bits -= kf_bits;
2011 // Save the bits to spend on the key frame.
2012 twopass->gf_group.bit_allocation[0] = kf_bits;
2013 twopass->gf_group.update_type[0] = KF_UPDATE;
2014 twopass->gf_group.rf_level[0] = KF_STD;
2016 // Note the total error score of the kf group minus the key frame itself.
2017 twopass->kf_group_error_left = (int)(kf_group_err - kf_mod_err);
2019 // Adjust the count of total modified error left.
2020 // The count of bits left is adjusted elsewhere based on real coded frame
2022 twopass->modified_error_left -= kf_group_err;
2025 // For VBR...adjustment to the frame target based on error from previous frames
2026 void vbr_rate_correction(int * this_frame_target,
2027 const int64_t vbr_bits_off_target) {
2028 int max_delta = (*this_frame_target * 15) / 100;
2030 // vbr_bits_off_target > 0 means we have extra bits to spend
2031 if (vbr_bits_off_target > 0) {
2032 *this_frame_target +=
2033 (vbr_bits_off_target > max_delta) ? max_delta
2034 : (int)vbr_bits_off_target;
2036 *this_frame_target -=
2037 (vbr_bits_off_target < -max_delta) ? max_delta
2038 : (int)-vbr_bits_off_target;
2042 // Define the reference buffers that will be updated post encode.
2043 void configure_buffer_updates(VP9_COMP *cpi) {
2044 TWO_PASS *const twopass = &cpi->twopass;
2046 cpi->rc.is_src_frame_alt_ref = 0;
2047 switch (twopass->gf_group.update_type[twopass->gf_group.index]) {
2049 cpi->refresh_last_frame = 1;
2050 cpi->refresh_golden_frame = 1;
2051 cpi->refresh_alt_ref_frame = 1;
2054 cpi->refresh_last_frame = 1;
2055 cpi->refresh_golden_frame = 0;
2056 cpi->refresh_alt_ref_frame = 0;
2059 cpi->refresh_last_frame = 1;
2060 cpi->refresh_golden_frame = 1;
2061 cpi->refresh_alt_ref_frame = 0;
2063 case OVERLAY_UPDATE:
2064 cpi->refresh_last_frame = 0;
2065 cpi->refresh_golden_frame = 1;
2066 cpi->refresh_alt_ref_frame = 0;
2067 cpi->rc.is_src_frame_alt_ref = 1;
2070 cpi->refresh_last_frame = 0;
2071 cpi->refresh_golden_frame = 0;
2072 cpi->refresh_alt_ref_frame = 1;
2080 void vp9_rc_get_second_pass_params(VP9_COMP *cpi) {
2081 VP9_COMMON *const cm = &cpi->common;
2082 RATE_CONTROL *const rc = &cpi->rc;
2083 TWO_PASS *const twopass = &cpi->twopass;
2085 FIRSTPASS_STATS this_frame;
2086 FIRSTPASS_STATS this_frame_copy;
2089 LAYER_CONTEXT *lc = NULL;
2090 const int is_spatial_svc = (cpi->use_svc &&
2091 cpi->svc.number_temporal_layers == 1);
2092 if (is_spatial_svc) {
2093 lc = &cpi->svc.layer_context[cpi->svc.spatial_layer_id];
2094 frames_left = (int)(twopass->total_stats.count -
2095 lc->current_video_frame_in_layer);
2097 frames_left = (int)(twopass->total_stats.count -
2098 cm->current_video_frame);
2101 if (!twopass->stats_in)
2104 // If this is an arf frame then we dont want to read the stats file or
2105 // advance the input pointer as we already have what we need.
2106 if (twopass->gf_group.update_type[twopass->gf_group.index] == ARF_UPDATE) {
2108 configure_buffer_updates(cpi);
2109 target_rate = twopass->gf_group.bit_allocation[twopass->gf_group.index];
2110 target_rate = vp9_rc_clamp_pframe_target_size(cpi, target_rate);
2111 rc->base_frame_target = target_rate;
2112 #ifdef LONG_TERM_VBR_CORRECTION
2113 // Correction to rate target based on prior over or under shoot.
2114 if (cpi->oxcf.rc_mode == VPX_VBR)
2115 vbr_rate_correction(&target_rate, rc->vbr_bits_off_target);
2117 vp9_rc_set_frame_target(cpi, target_rate);
2118 cm->frame_type = INTER_FRAME;
2122 vp9_clear_system_state();
2124 if (is_spatial_svc && twopass->kf_intra_err_min == 0) {
2125 twopass->kf_intra_err_min = KF_MB_INTRA_MIN * cpi->common.MBs;
2126 twopass->gf_intra_err_min = GF_MB_INTRA_MIN * cpi->common.MBs;
2129 if (cpi->oxcf.rc_mode == VPX_Q) {
2130 twopass->active_worst_quality = cpi->oxcf.cq_level;
2131 } else if (cm->current_video_frame == 0 ||
2132 (is_spatial_svc && lc->current_video_frame_in_layer == 0)) {
2133 // Special case code for first frame.
2134 const int section_target_bandwidth = (int)(twopass->bits_left /
2136 const int tmp_q = get_twopass_worst_quality(cpi, &twopass->total_left_stats,
2137 section_target_bandwidth);
2138 twopass->active_worst_quality = tmp_q;
2139 rc->ni_av_qi = tmp_q;
2140 rc->avg_q = vp9_convert_qindex_to_q(tmp_q);
2142 vp9_zero(this_frame);
2143 if (EOF == input_stats(twopass, &this_frame))
2146 // Local copy of the current frame's first pass stats.
2147 this_frame_copy = this_frame;
2149 // Keyframe and section processing.
2150 if (rc->frames_to_key == 0 ||
2151 (cpi->frame_flags & FRAMEFLAGS_KEY)) {
2152 // Define next KF group and assign bits to it.
2153 find_next_key_frame(cpi, &this_frame_copy);
2155 cm->frame_type = INTER_FRAME;
2158 if (is_spatial_svc) {
2159 if (cpi->svc.spatial_layer_id == 0) {
2160 lc->is_key_frame = (cm->frame_type == KEY_FRAME);
2162 cm->frame_type = INTER_FRAME;
2163 lc->is_key_frame = cpi->svc.layer_context[0].is_key_frame;
2165 if (lc->is_key_frame) {
2166 cpi->ref_frame_flags &= (~VP9_LAST_FLAG);
2171 // Define a new GF/ARF group. (Should always enter here for key frames).
2172 if (rc->frames_till_gf_update_due == 0) {
2173 define_gf_group(cpi, &this_frame_copy);
2175 if (twopass->gf_zeromotion_pct > 995) {
2176 // As long as max_thresh for encode breakout is small enough, it is ok
2177 // to enable it for show frame, i.e. set allow_encode_breakout to
2178 // ENCODE_BREAKOUT_LIMITED.
2179 if (!cm->show_frame)
2180 cpi->allow_encode_breakout = ENCODE_BREAKOUT_DISABLED;
2182 cpi->allow_encode_breakout = ENCODE_BREAKOUT_LIMITED;
2185 rc->frames_till_gf_update_due = rc->baseline_gf_interval;
2186 cpi->refresh_golden_frame = 1;
2190 FIRSTPASS_STATS next_frame;
2191 if (lookup_next_frame_stats(twopass, &next_frame) != EOF) {
2192 twopass->next_iiratio = (int)(next_frame.intra_error /
2193 DOUBLE_DIVIDE_CHECK(next_frame.coded_error));
2197 configure_buffer_updates(cpi);
2199 target_rate = twopass->gf_group.bit_allocation[twopass->gf_group.index];
2200 if (cpi->common.frame_type == KEY_FRAME)
2201 target_rate = vp9_rc_clamp_iframe_target_size(cpi, target_rate);
2203 target_rate = vp9_rc_clamp_pframe_target_size(cpi, target_rate);
2205 rc->base_frame_target = target_rate;
2206 #ifdef LONG_TERM_VBR_CORRECTION
2207 // Correction to rate target based on prior over or under shoot.
2208 if (cpi->oxcf.rc_mode == VPX_VBR)
2209 vbr_rate_correction(&target_rate, rc->vbr_bits_off_target);
2211 vp9_rc_set_frame_target(cpi, target_rate);
2213 // Update the total stats remaining structure.
2214 subtract_stats(&twopass->total_left_stats, &this_frame);
2216 #if CONFIG_FP_MB_STATS
2217 if (cpi->use_fp_mb_stats) {
2218 input_mb_stats(&twopass->this_frame_mb_stats, cm);
2223 void vp9_twopass_postencode_update(VP9_COMP *cpi) {
2224 TWO_PASS *const twopass = &cpi->twopass;
2225 RATE_CONTROL *const rc = &cpi->rc;
2226 #ifdef LONG_TERM_VBR_CORRECTION
2227 // In this experimental mode, the VBR correction is done exclusively through
2228 // rc->vbr_bits_off_target. Based on the sign of this value, a limited %
2229 // adjustment is made to the target rate of subsequent frames, to try and
2230 // push it back towards 0. This mode is less likely to suffer from
2231 // extreme behaviour at the end of a clip or group of frames.
2232 const int bits_used = rc->base_frame_target;
2233 rc->vbr_bits_off_target += rc->base_frame_target - rc->projected_frame_size;
2235 // In this mode, VBR correction is acheived by altering bits_left,
2236 // kf_group_bits & gf_group_bits to reflect any deviation from the target
2237 // rate in this frame. This alters the allocation of bits to the
2238 // remaning frames in the group / clip.
2240 // This method can give rise to unstable behaviour near the end of a clip
2241 // or kf/gf group of frames where any accumulated error is corrected over an
2242 // ever decreasing number of frames. Hence we change the balance of target
2243 // vs. actual bitrate gradually as we progress towards the end of the
2244 // sequence in order to mitigate this effect.
2245 const double progress =
2246 (double)(twopass->stats_in - twopass->stats_in_start) /
2247 (twopass->stats_in_end - twopass->stats_in_start);
2248 const int bits_used = (int)(progress * rc->this_frame_target +
2249 (1.0 - progress) * rc->projected_frame_size);
2252 twopass->bits_left = MAX(twopass->bits_left - bits_used, 0);
2254 #ifdef LONG_TERM_VBR_CORRECTION
2255 if (cpi->common.frame_type != KEY_FRAME &&
2256 !vp9_is_upper_layer_key_frame(cpi)) {
2258 if (cpi->common.frame_type == KEY_FRAME ||
2259 vp9_is_upper_layer_key_frame(cpi)) {
2260 // For key frames kf_group_bits already had the target bits subtracted out.
2261 // So now update to the correct value based on the actual bits used.
2262 twopass->kf_group_bits += rc->this_frame_target - bits_used;
2265 twopass->kf_group_bits -= bits_used;
2267 twopass->kf_group_bits = MAX(twopass->kf_group_bits, 0);
2269 // Increment the gf group index ready for the next frame.
2270 ++twopass->gf_group.index;