AOMedia AV1 Codec
rc_utils.h
1/*
2 * Copyright (c) 2020, Alliance for Open Media. All rights reserved
3 *
4 * This source code is subject to the terms of the BSD 2 Clause License and
5 * the Alliance for Open Media Patent License 1.0. If the BSD 2 Clause License
6 * was not distributed with this source code in the LICENSE file, you can
7 * obtain it at www.aomedia.org/license/software. If the Alliance for Open
8 * Media Patent License 1.0 was not distributed with this source code in the
9 * PATENTS file, you can obtain it at www.aomedia.org/license/patent.
10 */
11
12#ifndef AOM_AV1_ENCODER_RC_UTILS_H_
13#define AOM_AV1_ENCODER_RC_UTILS_H_
14
15#include "av1/encoder/encoder.h"
16#include "aom_dsp/psnr.h"
17
18#ifdef __cplusplus
19extern "C" {
20#endif
21
22static AOM_INLINE void check_reset_rc_flag(AV1_COMP *cpi) {
23 RATE_CONTROL *rc = &cpi->rc;
24 PRIMARY_RATE_CONTROL *const p_rc = &cpi->ppi->p_rc;
25 if (cpi->common.current_frame.frame_number >
26 (unsigned int)cpi->svc.number_spatial_layers) {
27 if (cpi->ppi->use_svc) {
28 av1_svc_check_reset_layer_rc_flag(cpi);
29 } else {
30 if (rc->avg_frame_bandwidth > (3 * rc->prev_avg_frame_bandwidth >> 1) ||
31 rc->avg_frame_bandwidth < (rc->prev_avg_frame_bandwidth >> 1)) {
32 rc->rc_1_frame = 0;
33 rc->rc_2_frame = 0;
36 }
37 }
38 }
39}
40
41static AOM_INLINE void set_primary_rc_buffer_sizes(const AV1EncoderConfig *oxcf,
42 AV1_PRIMARY *ppi) {
43 PRIMARY_RATE_CONTROL *p_rc = &ppi->p_rc;
44 const RateControlCfg *const rc_cfg = &oxcf->rc_cfg;
45
46 const int64_t bandwidth = rc_cfg->target_bandwidth;
47 const int64_t starting = rc_cfg->starting_buffer_level_ms;
48 const int64_t optimal = rc_cfg->optimal_buffer_level_ms;
49 const int64_t maximum = rc_cfg->maximum_buffer_size_ms;
50
51 p_rc->starting_buffer_level = starting * bandwidth / 1000;
53 (optimal == 0) ? bandwidth / 8 : optimal * bandwidth / 1000;
55 (maximum == 0) ? bandwidth / 8 : maximum * bandwidth / 1000;
56
57 // Under a configuration change, where maximum_buffer_size may change,
58 // keep buffer level clipped to the maximum allowed buffer size.
59 p_rc->bits_off_target =
60 AOMMIN(p_rc->bits_off_target, p_rc->maximum_buffer_size);
61 p_rc->buffer_level = AOMMIN(p_rc->buffer_level, p_rc->maximum_buffer_size);
62}
63
64static AOM_INLINE void config_target_level(AV1_COMP *const cpi,
65 AV1_LEVEL target_level, int tier) {
66 AV1EncoderConfig *const oxcf = &cpi->oxcf;
67 SequenceHeader *const seq_params = cpi->common.seq_params;
68 TileConfig *const tile_cfg = &oxcf->tile_cfg;
69 RateControlCfg *const rc_cfg = &oxcf->rc_cfg;
70
71 // Adjust target bitrate to be no larger than 70% of level limit.
72 const BITSTREAM_PROFILE profile = seq_params->profile;
73 const double level_bitrate_limit =
74 av1_get_max_bitrate_for_level(target_level, tier, profile);
75 const int64_t max_bitrate = (int64_t)(level_bitrate_limit * 0.70);
76 rc_cfg->target_bandwidth = AOMMIN(rc_cfg->target_bandwidth, max_bitrate);
77 // Also need to update cpi->ppi->twopass.bits_left.
78 TWO_PASS *const twopass = &cpi->ppi->twopass;
79 FIRSTPASS_STATS *stats = twopass->stats_buf_ctx->total_stats;
80 if (stats != NULL)
81 cpi->ppi->twopass.bits_left =
82 (int64_t)(stats->duration * rc_cfg->target_bandwidth / 10000000.0);
83
84 // Adjust max over-shoot percentage.
85 rc_cfg->over_shoot_pct = 0;
86
87 // Adjust max quantizer.
88 rc_cfg->worst_allowed_q = 255;
89
90 // Adjust number of tiles and tile columns to be under level limit.
91 int max_tiles, max_tile_cols;
92 av1_get_max_tiles_for_level(target_level, &max_tiles, &max_tile_cols);
93 while (tile_cfg->tile_columns > 0 &&
94 (1 << tile_cfg->tile_columns) > max_tile_cols) {
95 --tile_cfg->tile_columns;
96 }
97 const int tile_cols = (1 << tile_cfg->tile_columns);
98 while (tile_cfg->tile_rows > 0 &&
99 tile_cols * (1 << tile_cfg->tile_rows) > max_tiles) {
100 --tile_cfg->tile_rows;
101 }
102
103 // Adjust min compression ratio.
104 const int still_picture = seq_params->still_picture;
105 const double min_cr =
106 av1_get_min_cr_for_level(target_level, tier, still_picture);
107 rc_cfg->min_cr = AOMMAX(rc_cfg->min_cr, (unsigned int)(min_cr * 100));
108}
109
110#if !CONFIG_REALTIME_ONLY
111
128static AOM_INLINE int recode_loop_test(AV1_COMP *cpi, int high_limit,
129 int low_limit, int q, int maxq,
130 int minq) {
131 const RATE_CONTROL *const rc = &cpi->rc;
132 const AV1EncoderConfig *const oxcf = &cpi->oxcf;
133 const int frame_is_kfgfarf = frame_is_kf_gf_arf(cpi);
134 int force_recode = 0;
135
136 if ((rc->projected_frame_size >= rc->max_frame_bandwidth) ||
137 (cpi->sf.hl_sf.recode_loop == ALLOW_RECODE) ||
138 (frame_is_kfgfarf &&
139 (cpi->sf.hl_sf.recode_loop == ALLOW_RECODE_KFARFGF))) {
140 // TODO(agrange) high_limit could be greater than the scale-down threshold.
141 if ((rc->projected_frame_size > high_limit && q < maxq) ||
142 (rc->projected_frame_size < low_limit && q > minq)) {
143 force_recode = 1;
144 } else if (cpi->oxcf.rc_cfg.mode == AOM_CQ) {
145 // Deal with frame undershoot and whether or not we are
146 // below the automatically set cq level.
147 if (q > oxcf->rc_cfg.cq_level &&
148 rc->projected_frame_size < ((rc->this_frame_target * 7) >> 3)) {
149 force_recode = 1;
150 }
151 }
152 }
153 return force_recode;
154}
155
156static AOM_INLINE double av1_get_gfu_boost_projection_factor(double min_factor,
157 double max_factor,
158 int frame_count) {
159 double factor = sqrt((double)frame_count);
160 factor = AOMMIN(factor, max_factor);
161 factor = AOMMAX(factor, min_factor);
162 factor = (200.0 + 10.0 * factor);
163 return factor;
164}
165
166static AOM_INLINE int get_gfu_boost_from_r0_lap(double min_factor,
167 double max_factor, double r0,
168 int frames_to_key) {
169 double factor = av1_get_gfu_boost_projection_factor(min_factor, max_factor,
170 frames_to_key);
171 const int boost = (int)rint(factor / r0);
172 return boost;
173}
174
175static AOM_INLINE double av1_get_kf_boost_projection_factor(int frame_count) {
176 double factor = sqrt((double)frame_count);
177 factor = AOMMIN(factor, 10.0);
178 factor = AOMMAX(factor, 4.0);
179 factor = (75.0 + 14.0 * factor);
180 return factor;
181}
182
183static AOM_INLINE int get_regulated_q_overshoot(AV1_COMP *const cpi,
184#if CONFIG_FRAME_PARALLEL_ENCODE
185 int is_encode_stage,
186#endif
187 int q_low, int q_high,
188 int top_index,
189 int bottom_index) {
190 const AV1_COMMON *const cm = &cpi->common;
191 const RATE_CONTROL *const rc = &cpi->rc;
192
194#if CONFIG_FRAME_PARALLEL_ENCODE
195 is_encode_stage,
196#endif
197 cm->width, cm->height);
198
199 int q_regulated =
200 av1_rc_regulate_q(cpi, rc->this_frame_target, bottom_index,
201 AOMMAX(q_high, top_index), cm->width, cm->height);
202
203 int retries = 0;
204 while (q_regulated < q_low && retries < 10) {
206#if CONFIG_FRAME_PARALLEL_ENCODE
207 is_encode_stage,
208#endif
209 cm->width, cm->height);
210 q_regulated =
211 av1_rc_regulate_q(cpi, rc->this_frame_target, bottom_index,
212 AOMMAX(q_high, top_index), cm->width, cm->height);
213 retries++;
214 }
215 return q_regulated;
216}
217
218static AOM_INLINE int get_regulated_q_undershoot(AV1_COMP *const cpi,
219#if CONFIG_FRAME_PARALLEL_ENCODE
220 int is_encode_stage,
221#endif
222 int q_high, int top_index,
223 int bottom_index) {
224 const AV1_COMMON *const cm = &cpi->common;
225 const RATE_CONTROL *const rc = &cpi->rc;
226
228#if CONFIG_FRAME_PARALLEL_ENCODE
229 is_encode_stage,
230#endif
231 cm->width, cm->height);
232 int q_regulated = av1_rc_regulate_q(cpi, rc->this_frame_target, bottom_index,
233 top_index, cm->width, cm->height);
234
235 int retries = 0;
236 while (q_regulated > q_high && retries < 10) {
238#if CONFIG_FRAME_PARALLEL_ENCODE
239 is_encode_stage,
240#endif
241 cm->width, cm->height);
242 q_regulated = av1_rc_regulate_q(cpi, rc->this_frame_target, bottom_index,
243 top_index, cm->width, cm->height);
244 retries++;
245 }
246 return q_regulated;
247}
248
271static AOM_INLINE void recode_loop_update_q(
272 AV1_COMP *const cpi, int *const loop, int *const q, int *const q_low,
273 int *const q_high, const int top_index, const int bottom_index,
274 int *const undershoot_seen, int *const overshoot_seen,
275 int *const low_cr_seen, const int loop_count) {
276 AV1_COMMON *const cm = &cpi->common;
277 RATE_CONTROL *const rc = &cpi->rc;
278 PRIMARY_RATE_CONTROL *const p_rc = &cpi->ppi->p_rc;
279 const RateControlCfg *const rc_cfg = &cpi->oxcf.rc_cfg;
280 *loop = 0;
281
282 // Special case for overlay frame.
283 if (rc->is_src_frame_alt_ref &&
284 rc->projected_frame_size < rc->max_frame_bandwidth)
285 return;
286
287 const int min_cr = rc_cfg->min_cr;
288 if (min_cr > 0) {
289 const double compression_ratio =
290 av1_get_compression_ratio(cm, rc->projected_frame_size >> 3);
291 const double target_cr = min_cr / 100.0;
292 if (compression_ratio < target_cr) {
293 *low_cr_seen = 1;
294 if (*q < rc->worst_quality) {
295 const double cr_ratio = target_cr / compression_ratio;
296 const int projected_q = AOMMAX(*q + 1, (int)(*q * cr_ratio * cr_ratio));
297 *q = AOMMIN(AOMMIN(projected_q, *q + 32), rc->worst_quality);
298 *q_low = AOMMAX(*q, *q_low);
299 *q_high = AOMMAX(*q, *q_high);
300 *loop = 1;
301 }
302 }
303 if (*low_cr_seen) return;
304 }
305
306 if (cpi->ppi->level_params.keep_level_stats &&
307 !is_stat_generation_stage(cpi)) {
308 // Initialize level info. at the beginning of each sequence.
309 if (cm->current_frame.frame_type == KEY_FRAME &&
310 cpi->ppi->gf_group.refbuf_state[cpi->gf_frame_index] == REFBUF_RESET) {
311 av1_init_level_info(cpi);
312 }
313 const AV1LevelParams *const level_params = &cpi->ppi->level_params;
314 // TODO(any): currently only checking operating point 0
315 const AV1LevelInfo *const level_info = level_params->level_info[0];
316 const DECODER_MODEL *const decoder_models = level_info->decoder_models;
317 const AV1_LEVEL target_level = level_params->target_seq_level_idx[0];
318
319 if (target_level < SEQ_LEVELS) {
320 DECODER_MODEL_STATUS status = av1_decoder_model_try_smooth_buf(
321 cpi, rc->projected_frame_size, &decoder_models[target_level]);
322
323 if ((status == SMOOTHING_BUFFER_UNDERFLOW ||
324 status == SMOOTHING_BUFFER_OVERFLOW) &&
325 *q < rc->worst_quality) {
326 *q = AOMMIN(*q + 10, rc->worst_quality);
327 *q_low = AOMMAX(*q, *q_low);
328 *q_high = AOMMAX(*q, *q_high);
329 *loop = 1;
330 return;
331 }
332 }
333 }
334
335 if (rc_cfg->mode == AOM_Q) return;
336
337 const int last_q = *q;
338 int frame_over_shoot_limit = 0, frame_under_shoot_limit = 0;
339 av1_rc_compute_frame_size_bounds(cpi, rc->this_frame_target,
340 &frame_under_shoot_limit,
341 &frame_over_shoot_limit);
342 if (frame_over_shoot_limit == 0) frame_over_shoot_limit = 1;
343
344 if (cm->current_frame.frame_type == KEY_FRAME &&
345 p_rc->this_key_frame_forced &&
346 rc->projected_frame_size < rc->max_frame_bandwidth) {
347 int64_t kf_err;
348 const int64_t high_err_target = cpi->ambient_err;
349 const int64_t low_err_target = cpi->ambient_err >> 1;
350
351#if CONFIG_AV1_HIGHBITDEPTH
352 if (cm->seq_params->use_highbitdepth) {
353 kf_err = aom_highbd_get_y_sse(cpi->source, &cm->cur_frame->buf);
354 } else {
355 kf_err = aom_get_y_sse(cpi->source, &cm->cur_frame->buf);
356 }
357#else
358 kf_err = aom_get_y_sse(cpi->source, &cm->cur_frame->buf);
359#endif
360 // Prevent possible divide by zero error below for perfect KF
361 kf_err += !kf_err;
362
363 // The key frame is not good enough or we can afford
364 // to make it better without undue risk of popping.
365 if ((kf_err > high_err_target &&
366 rc->projected_frame_size <= frame_over_shoot_limit) ||
367 (kf_err > low_err_target &&
368 rc->projected_frame_size <= frame_under_shoot_limit)) {
369 // Lower q_high
370 *q_high = AOMMAX(*q - 1, *q_low);
371
372 // Adjust Q
373 *q = (int)((*q * high_err_target) / kf_err);
374 *q = AOMMIN(*q, (*q_high + *q_low) >> 1);
375 } else if (kf_err < low_err_target &&
376 rc->projected_frame_size >= frame_under_shoot_limit) {
377 // The key frame is much better than the previous frame
378 // Raise q_low
379 *q_low = AOMMIN(*q + 1, *q_high);
380
381 // Adjust Q
382 *q = (int)((*q * low_err_target) / kf_err);
383 *q = AOMMIN(*q, (*q_high + *q_low + 1) >> 1);
384 }
385
386 // Clamp Q to upper and lower limits:
387 *q = clamp(*q, *q_low, *q_high);
388 *loop = (*q != last_q);
389 return;
390 }
391
392 if (recode_loop_test(cpi, frame_over_shoot_limit, frame_under_shoot_limit, *q,
393 AOMMAX(*q_high, top_index), bottom_index)) {
394 // Is the projected frame size out of range and are we allowed
395 // to attempt to recode.
396
397 // Frame size out of permitted range:
398 // Update correction factor & compute new Q to try...
399 // Frame is too large
401 // Special case if the projected size is > the max allowed.
402 if (*q == *q_high &&
403 rc->projected_frame_size >= rc->max_frame_bandwidth) {
404 const double q_val_high_current =
405 av1_convert_qindex_to_q(*q_high, cm->seq_params->bit_depth);
406 const double q_val_high_new =
407 q_val_high_current *
408 ((double)rc->projected_frame_size / rc->max_frame_bandwidth);
409 *q_high = av1_find_qindex(q_val_high_new, cm->seq_params->bit_depth,
410 rc->best_quality, rc->worst_quality);
411 }
412
413 // Raise Qlow as to at least the current value
414 *q_low = AOMMIN(*q + 1, *q_high);
415
416 if (*undershoot_seen || loop_count > 2 ||
417 (loop_count == 2 && !frame_is_intra_only(cm))) {
419#if CONFIG_FRAME_PARALLEL_ENCODE
420 1,
421#endif
422 cm->width, cm->height);
423
424 *q = (*q_high + *q_low + 1) / 2;
425 } else if (loop_count == 2 && frame_is_intra_only(cm)) {
426 const int q_mid = (*q_high + *q_low + 1) / 2;
427 const int q_regulated =
428 get_regulated_q_overshoot(cpi,
429#if CONFIG_FRAME_PARALLEL_ENCODE
430 1,
431#endif
432 *q_low, *q_high, top_index, bottom_index);
433 // Get 'q' in-between 'q_mid' and 'q_regulated' for a smooth
434 // transition between loop_count < 2 and loop_count > 2.
435 *q = (q_mid + q_regulated + 1) / 2;
436 } else {
437 *q =
438 get_regulated_q_overshoot(cpi,
439#if CONFIG_FRAME_PARALLEL_ENCODE
440 1,
441#endif
442 *q_low, *q_high, top_index, bottom_index);
443 }
444
445 *overshoot_seen = 1;
446 } else {
447 // Frame is too small
448 *q_high = AOMMAX(*q - 1, *q_low);
449
450 if (*overshoot_seen || loop_count > 2 ||
451 (loop_count == 2 && !frame_is_intra_only(cm))) {
453#if CONFIG_FRAME_PARALLEL_ENCODE
454 1,
455#endif
456 cm->width, cm->height);
457 *q = (*q_high + *q_low) / 2;
458 } else if (loop_count == 2 && frame_is_intra_only(cm)) {
459 const int q_mid = (*q_high + *q_low) / 2;
460 const int q_regulated =
461 get_regulated_q_undershoot(cpi,
462#if CONFIG_FRAME_PARALLEL_ENCODE
463 1,
464#endif
465 *q_high, top_index, bottom_index);
466 // Get 'q' in-between 'q_mid' and 'q_regulated' for a smooth
467 // transition between loop_count < 2 and loop_count > 2.
468 *q = (q_mid + q_regulated) / 2;
469
470 // Special case reset for qlow for constrained quality.
471 // This should only trigger where there is very substantial
472 // undershoot on a frame and the auto cq level is above
473 // the user passsed in value.
474 if (rc_cfg->mode == AOM_CQ && q_regulated < *q_low) {
475 *q_low = *q;
476 }
477 } else {
478 *q = get_regulated_q_undershoot(cpi,
479#if CONFIG_FRAME_PARALLEL_ENCODE
480 1,
481#endif
482 *q_high, top_index, bottom_index);
483
484 // Special case reset for qlow for constrained quality.
485 // This should only trigger where there is very substantial
486 // undershoot on a frame and the auto cq level is above
487 // the user passsed in value.
488 if (rc_cfg->mode == AOM_CQ && *q < *q_low) {
489 *q_low = *q;
490 }
491 }
492
493 *undershoot_seen = 1;
494 }
495
496 // Clamp Q to upper and lower limits:
497 *q = clamp(*q, *q_low, *q_high);
498 }
499
500 *loop = (*q != last_q);
501}
502#endif
503
504#ifdef __cplusplus
505} // extern "C"
506#endif
507
508#endif // AOM_AV1_ENCODER_RC_UTILS_H_
Declares top-level encoder structures and functions.
@ AOM_CQ
Definition aom_encoder.h:187
@ AOM_Q
Definition aom_encoder.h:188
static int recode_loop_test(AV1_COMP *cpi, int high_limit, int low_limit, int q, int maxq, int minq)
Function to test for conditions that indicate we should loop back and recode a frame.
Definition rc_utils.h:128
static void recode_loop_update_q(AV1_COMP *const cpi, int *const loop, int *const q, int *const q_low, int *const q_high, const int top_index, const int bottom_index, int *const undershoot_seen, int *const overshoot_seen, int *const low_cr_seen, const int loop_count)
Called after encode_with_recode_loop() has just encoded a frame. This function works out whether we u...
Definition rc_utils.h:271
void av1_rc_update_rate_correction_factors(AV1_COMP *cpi, int width, int height)
Updates the rate correction factor linking Q to output bits.
Definition ratectrl.c:648
Top level common structure used by both encoder and decoder.
Definition av1_common_int.h:755
SequenceHeader * seq_params
Definition av1_common_int.h:981
int width
Definition av1_common_int.h:780
RefCntBuffer * cur_frame
Definition av1_common_int.h:837
CurrentFrame current_frame
Definition av1_common_int.h:759
int height
Definition av1_common_int.h:781
The stucture of acummulated frame stats in the first pass.
Definition firstpass.h:41
double duration
Definition firstpass.h:142
Primary Rate Control parameters and status.
Definition ratectrl.h:243
int64_t bits_off_target
Definition ratectrl.h:503
int64_t maximum_buffer_size
Definition ratectrl.h:300
int64_t starting_buffer_level
Definition ratectrl.h:290
int64_t buffer_level
Definition ratectrl.h:482
int64_t optimal_buffer_level
Definition ratectrl.h:295
Rate Control parameters and status.
Definition ratectrl.h:121
int best_quality
Definition ratectrl.h:202
int this_frame_target
Definition ratectrl.h:132
int projected_frame_size
Definition ratectrl.h:137
int worst_quality
Definition ratectrl.h:198
Two pass status and control data.
Definition firstpass.h:412