AOMedia AV1 Codec
ratectrl.h
1 /*
2  * Copyright (c) 2016, 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_RATECTRL_H_
13 #define AOM_AV1_ENCODER_RATECTRL_H_
14 
15 #include "aom/aom_codec.h"
16 #include "aom/aom_integer.h"
17 
18 #include "aom_ports/mem.h"
19 
20 #include "av1/common/av1_common_int.h"
21 #include "av1/common/blockd.h"
22 
23 #ifdef __cplusplus
24 extern "C" {
25 #endif
26 
29 // Bits Per MB at different Q (Multiplied by 512)
30 #define BPER_MB_NORMBITS 9
31 
32 // Use this macro to turn on/off use of alt-refs in one-pass mode.
33 #define USE_ALTREF_FOR_ONE_PASS 1
34 
35 // Threshold used to define if a KF group is static (e.g. a slide show).
36 // Essentially, this means that no frame in the group has more than 1% of MBs
37 // that are not marked as coded with 0,0 motion in the first pass.
38 #define STATIC_KF_GROUP_THRESH 99
39 #define STATIC_KF_GROUP_FLOAT_THRESH 0.99
40 
41 // The maximum duration of a GF group that is static (e.g. a slide show).
42 #define MAX_STATIC_GF_GROUP_LENGTH 250
43 
44 #define MIN_GF_INTERVAL 4
45 #define MAX_GF_INTERVAL 32
46 #define FIXED_GF_INTERVAL 16
47 #define MAX_GF_LENGTH_LAP 16
48 
49 #define MAX_NUM_GF_INTERVALS 15
50 
51 #define MAX_ARF_LAYERS 6
52 // #define STRICT_RC
53 
54 typedef struct {
55  int resize_width;
56  int resize_height;
57  uint8_t superres_denom;
58 } size_params_type;
59 
60 enum {
61  INTER_NORMAL,
62  GF_ARF_LOW,
63  GF_ARF_STD,
64  KF_STD,
65  RATE_FACTOR_LEVELS
66 } UENUM1BYTE(RATE_FACTOR_LEVEL);
67 
68 enum {
69  KF_UPDATE,
70  LF_UPDATE,
71  GF_UPDATE,
72  ARF_UPDATE,
73  OVERLAY_UPDATE,
74  INTNL_OVERLAY_UPDATE, // Internal Overlay Frame
75  INTNL_ARF_UPDATE, // Internal Altref Frame
76  FRAME_UPDATE_TYPES
77 } UENUM1BYTE(FRAME_UPDATE_TYPE);
78 
79 enum {
80  REFBUF_RESET, // Clear reference frame buffer
81  REFBUF_UPDATE, // Refresh reference frame buffer
82  REFBUF_STATES
83 } UENUM1BYTE(REFBUF_STATE);
84 
85 typedef enum {
86  NO_RESIZE = 0,
87  DOWN_THREEFOUR = 1, // From orig to 3/4.
88  DOWN_ONEHALF = 2, // From orig or 3/4 to 1/2.
89  UP_THREEFOUR = -1, // From 1/2 to 3/4.
90  UP_ORIG = -2, // From 1/2 or 3/4 to orig.
91 } RESIZE_ACTION;
92 
93 typedef enum { ORIG = 0, THREE_QUARTER = 1, ONE_HALF = 2 } RESIZE_STATE;
94 
95 #define MAX_FIRSTPASS_ANALYSIS_FRAMES 150
96 typedef enum region_types {
97  STABLE_REGION = 0,
98  HIGH_VAR_REGION = 1,
99  SCENECUT_REGION = 2,
100  BLENDING_REGION = 3,
101 } REGION_TYPES;
102 
103 typedef struct regions {
104  int start;
105  int last;
106  double avg_noise_var;
107  double avg_cor_coeff;
108  double avg_sr_fr_ratio;
109  double avg_intra_err;
110  double avg_coded_err;
111  REGION_TYPES type;
112 } REGIONS;
113 
118 typedef struct {
119  // Rate targetting variables
120 
129  int this_frame_target; // Actual frame target after rc adjustment.
130 
134  int64_t gf_group_bits;
135 
140 
145 
150 
154  int last_q[FRAME_TYPES];
155 
160 
165 
173  int kf_boost;
174 
179  double rate_correction_factors[RATE_FACTOR_LEVELS];
180 
185 
190 
195 
199  int gf_intervals[MAX_NUM_GF_INTERVALS];
200 
205 
207  int num_regions;
208  REGIONS regions[MAX_FIRSTPASS_ANALYSIS_FRAMES];
209  double cor_coeff[MAX_FIRSTPASS_ANALYSIS_FRAMES];
210  double noise_var[MAX_FIRSTPASS_ANALYSIS_FRAMES];
211  int regions_offset; // offset of regions from the last keyframe
212  int frames_till_regions_update;
213 
214  int min_gf_interval;
215  int max_gf_interval;
216  int static_scene_max_gf_interval;
217  int baseline_gf_interval;
218  int constrained_gf_group;
225  int frames_since_key;
226  int this_key_frame_forced;
227  int next_key_frame_forced;
228  int is_src_frame_alt_ref;
229  int sframe_due;
230 
231  int high_source_sad;
232  uint64_t avg_source_sad;
233  uint64_t prev_avg_source_sad;
234 
235  int avg_frame_bandwidth; // Average frame size target for clip
236  int min_frame_bandwidth; // Minimum allocation used for any frame
237  int max_frame_bandwidth; // Maximum burst rate allowed for a frame.
238  int prev_avg_frame_bandwidth;
239 
240  int ni_av_qi;
241  int ni_tot_qi;
242  int ni_frames;
243  int avg_frame_qindex[FRAME_TYPES];
244  double tot_q;
245  double avg_q;
246 
247  int64_t buffer_level;
248  int64_t bits_off_target;
249  int64_t vbr_bits_off_target;
250  int64_t vbr_bits_off_target_fast;
251 
252  int decimation_factor;
253  int decimation_count;
254 
255  int rolling_target_bits;
256  int rolling_actual_bits;
257 
258  int rate_error_estimate;
259 
260  int64_t total_actual_bits;
261  int64_t total_target_bits;
262 
272 
287  // rate control history for last frame(1) and the frame before(2).
288  // -1: undershot
289  // 1: overshoot
290  // 0: not initialized.
291  int rc_1_frame;
292  int rc_2_frame;
293  int q_1_frame;
294  int q_2_frame;
295 
296  float_t arf_boost_factor;
297 
302  int arf_q;
310  int active_best_quality[MAX_ARF_LAYERS + 1];
311 
313  int base_layer_qp;
314 
315  // Total number of stats used only for kf_boost calculation.
316  int num_stats_used_for_kf_boost;
317  // Total number of stats used only for gfu_boost calculation.
318  int num_stats_used_for_gfu_boost;
319  // Total number of stats required by gfu_boost calculation.
320  int num_stats_required_for_gfu_boost;
321  int next_is_fwd_key;
322  int enable_scenecut_detection;
323  int use_arf_in_this_kf_group;
324  // Track amount of low motion in scene
325  int avg_frame_low_motion;
326 
327  // For dynamic resize, 1 pass cbr.
328  RESIZE_STATE resize_state;
329  int resize_avg_qp;
330  int resize_buffer_underflow;
331  int resize_count;
333 } RATE_CONTROL;
334 
337 struct AV1_COMP;
338 struct AV1EncoderConfig;
339 
340 void av1_rc_init(const struct AV1EncoderConfig *oxcf, int pass,
341  RATE_CONTROL *rc);
342 
343 int av1_estimate_bits_at_q(FRAME_TYPE frame_kind, int q, int mbs,
344  double correction_factor, aom_bit_depth_t bit_depth,
345  const int is_screen_content_type);
346 
347 double av1_convert_qindex_to_q(int qindex, aom_bit_depth_t bit_depth);
348 
349 void av1_rc_init_minq_luts(void);
350 
351 int av1_rc_get_default_min_gf_interval(int width, int height, double framerate);
352 // Note av1_rc_get_default_max_gf_interval() requires the min_gf_interval to
353 // be passed in to ensure that the max_gf_interval returned is at least as bis
354 // as that.
355 int av1_rc_get_default_max_gf_interval(double framerate, int min_gf_interval);
356 
357 // Generally at the high level, the following flow is expected
358 // to be enforced for rate control:
359 // First call per frame, one of:
360 // av1_rc_get_first_pass_params()
361 // av1_rc_get_second_pass_params()
362 // depending on the usage to set the rate control encode parameters desired.
363 //
364 // Then, call encode_frame_to_data_rate() to perform the
365 // actual encode. This function will in turn call encode_frame()
366 // one or more times, followed by one of:
367 // av1_rc_postencode_update()
368 // av1_rc_postencode_update_drop_frame()
369 //
370 // The majority of rate control parameters are only expected
371 // to be set in the av1_rc_get_..._params() functions and
372 // updated during the av1_rc_postencode_update...() functions.
373 // The only exceptions are av1_rc_drop_frame() and
374 // av1_rc_update_rate_correction_factors() functions.
375 
376 // Functions to set parameters for encoding before the actual
377 // encode_frame_to_data_rate() function.
378 struct EncodeFrameParams;
379 
380 // Post encode update of the rate control parameters based
381 // on bytes used
382 void av1_rc_postencode_update(struct AV1_COMP *cpi, uint64_t bytes_used);
383 // Post encode update of the rate control parameters for dropped frames
384 void av1_rc_postencode_update_drop_frame(struct AV1_COMP *cpi);
385 
399 void av1_rc_update_rate_correction_factors(struct AV1_COMP *cpi, int width,
400  int height);
403 // Decide if we should drop this frame: For 1-pass CBR.
404 // Changes only the decimation count in the rate control structure
405 int av1_rc_drop_frame(struct AV1_COMP *cpi);
406 
407 // Computes frame size bounds.
408 void av1_rc_compute_frame_size_bounds(const struct AV1_COMP *cpi,
409  int this_frame_target,
410  int *frame_under_shoot_limit,
411  int *frame_over_shoot_limit);
412 
428 int av1_rc_pick_q_and_bounds(const struct AV1_COMP *cpi, RATE_CONTROL *rc,
429  int width, int height, int gf_index,
430  int *bottom_index, int *top_index);
431 
444 int av1_rc_regulate_q(const struct AV1_COMP *cpi, int target_bits_per_frame,
445  int active_best_quality, int active_worst_quality,
446  int width, int height);
447 
449 // Estimates bits per mb for a given qindex and correction factor.
450 int av1_rc_bits_per_mb(FRAME_TYPE frame_type, int qindex,
451  double correction_factor, aom_bit_depth_t bit_depth,
452  const int is_screen_content_type);
453 
454 // Clamping utilities for bitrate targets for iframes and pframes.
455 int av1_rc_clamp_iframe_target_size(const struct AV1_COMP *const cpi,
456  int target);
457 int av1_rc_clamp_pframe_target_size(const struct AV1_COMP *const cpi,
458  int target, uint8_t frame_update_type);
459 
460 // Find q_index corresponding to desired_q, within [best_qindex, worst_qindex].
461 // To be precise, 'q_index' is the smallest integer, for which the corresponding
462 // q >= desired_q.
463 // If no such q index is found, returns 'worst_qindex'.
464 int av1_find_qindex(double desired_q, aom_bit_depth_t bit_depth,
465  int best_qindex, int worst_qindex);
466 
467 // Computes a q delta (in "q index" terms) to get from a starting q value
468 // to a target q value
469 int av1_compute_qdelta(const RATE_CONTROL *rc, double qstart, double qtarget,
470  aom_bit_depth_t bit_depth);
471 
472 // Computes a q delta (in "q index" terms) to get from a starting q value
473 // to a value that should equate to the given rate ratio.
474 int av1_compute_qdelta_by_rate(const RATE_CONTROL *rc, FRAME_TYPE frame_type,
475  int qindex, double rate_target_ratio,
476  const int is_screen_content_type,
477  aom_bit_depth_t bit_depth);
478 
479 int av1_frame_type_qdelta(const struct AV1_COMP *cpi, int q);
480 
481 void av1_rc_update_framerate(struct AV1_COMP *cpi, int width, int height);
482 
483 void av1_rc_set_gf_interval_range(const struct AV1_COMP *const cpi,
484  RATE_CONTROL *const rc);
485 
486 void av1_set_target_rate(struct AV1_COMP *cpi, int width, int height);
487 
488 int av1_resize_one_pass_cbr(struct AV1_COMP *cpi);
489 
490 void av1_rc_set_frame_target(struct AV1_COMP *cpi, int target, int width,
491  int height);
492 
494  int gf_update);
495 
509  const struct AV1_COMP *const cpi, FRAME_UPDATE_TYPE frame_update_type);
510 
521 int av1_calc_iframe_target_size_one_pass_vbr(const struct AV1_COMP *const cpi);
522 
535  const struct AV1_COMP *cpi, FRAME_UPDATE_TYPE frame_update_type);
536 
548 
565 void av1_get_one_pass_rt_params(struct AV1_COMP *cpi,
566  struct EncodeFrameParams *const frame_params,
567  unsigned int frame_flags);
568 
583 int av1_encodedframe_overshoot_cbr(struct AV1_COMP *cpi, int *q);
584 
585 #ifdef __cplusplus
586 } // extern "C"
587 #endif
588 
589 #endif // AOM_AV1_ENCODER_RATECTRL_H_
int av1_calc_pframe_target_size_one_pass_vbr(const struct AV1_COMP *const cpi, FRAME_UPDATE_TYPE frame_update_type)
Calculates how many bits to use for a P frame in one pass vbr.
Rate Control parameters and status.
Definition: ratectrl.h:118
FRAME_TYPE frame_type
Definition: encoder.h:2734
int av1_rc_regulate_q(const struct AV1_COMP *cpi, int target_bits_per_frame, int active_best_quality, int active_worst_quality, int width, int height)
Estimates q to achieve a target bits per frame.
int active_worst_quality
Definition: ratectrl.h:306
int64_t gf_group_bits
Definition: ratectrl.h:134
int cur_gf_index
Definition: ratectrl.h:204
void av1_rc_update_rate_correction_factors(struct AV1_COMP *cpi, int width, int height)
Updates the rate correction factor linking Q to output bits.
Definition: ratectrl.c:544
void av1_get_one_pass_rt_params(struct AV1_COMP *cpi, struct EncodeFrameParams *const frame_params, unsigned int frame_flags)
Setup the rate control parameters for 1 pass real-time mode.
Definition: ratectrl.c:2551
int av1_encodedframe_overshoot_cbr(struct AV1_COMP *cpi, int *q)
Increase q on expected encoder overshoot, for CBR mode.
Definition: ratectrl.c:2653
int intervals_till_gf_calculate_due
Definition: ratectrl.h:194
Describes the codec algorithm interface to applications.
int last_kf_qindex
Definition: ratectrl.h:164
int av1_calc_pframe_target_size_one_pass_cbr(const struct AV1_COMP *cpi, FRAME_UPDATE_TYPE frame_update_type)
Calculates how many bits to use for a P frame in one pass cbr.
contains per-frame encoding parameters decided upon by av1_encode_strategy() and passed down to av1_e...
Definition: encoder.h:2726
int av1_rc_pick_q_and_bounds(const struct AV1_COMP *cpi, RATE_CONTROL *rc, int width, int height, int gf_index, int *bottom_index, int *top_index)
Picks q and q bounds given the rate control parameters in cpi->rc.
int frames_to_key
Definition: ratectrl.h:223
int64_t optimal_buffer_level
Definition: ratectrl.h:280
int projected_frame_size
Definition: ratectrl.h:139
int64_t maximum_buffer_size
Definition: ratectrl.h:284
int av1_calc_iframe_target_size_one_pass_vbr(const struct AV1_COMP *const cpi)
Calculates how many bits to use for an i frame in one pass vbr.
int best_quality
Definition: ratectrl.h:271
enum aom_enc_pass pass
Definition: encoder.h:930
Top level encoder structure.
Definition: encoder.h:2095
int sb64_target_rate
Definition: ratectrl.h:149
enum aom_bit_depth aom_bit_depth_t
Bit depth for codecThis enumeration determines the bit depth of the codec.
int kf_boost
Definition: ratectrl.h:173
int base_frame_target
Definition: ratectrl.h:125
int64_t starting_buffer_level
Definition: ratectrl.h:276
int coefficient_size
Definition: ratectrl.h:144
int frames_till_gf_update_due
Definition: ratectrl.h:189
int frames_since_golden
Definition: ratectrl.h:184
int this_frame_target
Definition: ratectrl.h:129
int av1_calc_iframe_target_size_one_pass_cbr(const struct AV1_COMP *cpi)
Calculates how many bits to use for an i frame in one pass cbr.
int last_boosted_qindex
Definition: ratectrl.h:159
Main encoder configuration data structure.
Definition: encoder.h:805
int arf_q
Definition: ratectrl.h:302
int gfu_boost
Definition: ratectrl.h:169
int worst_quality
Definition: ratectrl.h:267
void av1_set_reference_structure_one_pass_rt(AV1_COMP *cpi, int gf_update)
Setup the reference prediction structure for 1 pass real-time.
Definition: ratectrl.c:2171