ref: 4c0a62312430eeb2b2d59d5ffab95770c4b01f1a
dir: /vp9/encoder/vp9_ratectrl.c/
/*
* Copyright (c) 2010 The WebM project authors. All Rights Reserved.
*
* Use of this source code is governed by a BSD-style license
* that can be found in the LICENSE file in the root of the source
* tree. An additional intellectual property rights grant can be found
* in the file PATENTS. All contributing project authors may
* be found in the AUTHORS file in the root of the source tree.
*/
#include <stdlib.h>
#include <stdio.h>
#include <string.h>
#include <limits.h>
#include <assert.h>
#include <math.h>
#include "vp9/common/vp9_alloccommon.h"
#include "vp9/common/vp9_common.h"
#include "vp9/encoder/vp9_ratectrl.h"
#include "vp9/common/vp9_entropymode.h"
#include "vpx_mem/vpx_mem.h"
#include "vp9/common/vp9_systemdependent.h"
#include "vp9/encoder/vp9_encodemv.h"
#include "vp9/common/vp9_quant_common.h"
#include "vp9/common/vp9_seg_common.h"
#define LIMIT_QRANGE_FOR_ALTREF_AND_KEY 1
#define MIN_BPB_FACTOR 0.005
#define MAX_BPB_FACTOR 50
// Bits Per MB at different Q (Multiplied by 512)
#define BPER_MB_NORMBITS 9
// Tables relating active max Q to active min Q
static int kf_low_motion_minq[QINDEX_RANGE];
static int kf_high_motion_minq[QINDEX_RANGE];
static int gf_low_motion_minq[QINDEX_RANGE];
static int gf_high_motion_minq[QINDEX_RANGE];
static int inter_minq[QINDEX_RANGE];
static int afq_low_motion_minq[QINDEX_RANGE];
static int afq_high_motion_minq[QINDEX_RANGE];
static int gf_high = 2000;
static int gf_low = 400;
static int kf_high = 5000;
static int kf_low = 400;
// Functions to compute the active minq lookup table entries based on a
// formulaic approach to facilitate easier adjustment of the Q tables.
// The formulae were derived from computing a 3rd order polynomial best
// fit to the original data (after plotting real maxq vs minq (not q index))
static int calculate_minq_index(double maxq,
double x3, double x2, double x1, double c) {
int i;
const double minqtarget = MIN(((x3 * maxq + x2) * maxq + x1) * maxq + c,
maxq);
// Special case handling to deal with the step from q2.0
// down to lossless mode represented by q 1.0.
if (minqtarget <= 2.0)
return 0;
for (i = 0; i < QINDEX_RANGE; i++) {
if (minqtarget <= vp9_convert_qindex_to_q(i))
return i;
}
return QINDEX_RANGE - 1;
}
void vp9_rc_init_minq_luts(void) {
int i;
for (i = 0; i < QINDEX_RANGE; i++) {
const double maxq = vp9_convert_qindex_to_q(i);
kf_low_motion_minq[i] = calculate_minq_index(maxq,
0.000001,
-0.0004,
0.15,
0.0);
kf_high_motion_minq[i] = calculate_minq_index(maxq,
0.000002,
-0.0012,
0.50,
0.0);
gf_low_motion_minq[i] = calculate_minq_index(maxq,
0.0000015,
-0.0009,
0.32,
0.0);
gf_high_motion_minq[i] = calculate_minq_index(maxq,
0.0000021,
-0.00125,
0.50,
0.0);
afq_low_motion_minq[i] = calculate_minq_index(maxq,
0.0000015,
-0.0009,
0.33,
0.0);
afq_high_motion_minq[i] = calculate_minq_index(maxq,
0.0000021,
-0.00125,
0.55,
0.0);
inter_minq[i] = calculate_minq_index(maxq,
0.00000271,
-0.00113,
0.75,
0.0);
}
}
// These functions use formulaic calculations to make playing with the
// quantizer tables easier. If necessary they can be replaced by lookup
// tables if and when things settle down in the experimental bitstream
double vp9_convert_qindex_to_q(int qindex) {
// Convert the index to a real Q value (scaled down to match old Q values)
return vp9_ac_quant(qindex, 0) / 4.0;
}
int vp9_rc_bits_per_mb(FRAME_TYPE frame_type, int qindex,
double correction_factor) {
const double q = vp9_convert_qindex_to_q(qindex);
int enumerator = frame_type == KEY_FRAME ? 3300000 : 2250000;
// q based adjustment to baseline enumerator
enumerator += (int)(enumerator * q) >> 12;
return (int)(0.5 + (enumerator * correction_factor / q));
}
void vp9_save_coding_context(VP9_COMP *cpi) {
CODING_CONTEXT *const cc = &cpi->coding_context;
VP9_COMMON *cm = &cpi->common;
// Stores a snapshot of key state variables which can subsequently be
// restored with a call to vp9_restore_coding_context. These functions are
// intended for use in a re-code loop in vp9_compress_frame where the
// quantizer value is adjusted between loop iterations.
vp9_copy(cc->nmvjointcost, cpi->mb.nmvjointcost);
vp9_copy(cc->nmvcosts, cpi->mb.nmvcosts);
vp9_copy(cc->nmvcosts_hp, cpi->mb.nmvcosts_hp);
vp9_copy(cc->segment_pred_probs, cm->seg.pred_probs);
vpx_memcpy(cpi->coding_context.last_frame_seg_map_copy,
cm->last_frame_seg_map, (cm->mi_rows * cm->mi_cols));
vp9_copy(cc->last_ref_lf_deltas, cm->lf.last_ref_deltas);
vp9_copy(cc->last_mode_lf_deltas, cm->lf.last_mode_deltas);
cc->fc = cm->fc;
}
void vp9_restore_coding_context(VP9_COMP *cpi) {
CODING_CONTEXT *const cc = &cpi->coding_context;
VP9_COMMON *cm = &cpi->common;
// Restore key state variables to the snapshot state stored in the
// previous call to vp9_save_coding_context.
vp9_copy(cpi->mb.nmvjointcost, cc->nmvjointcost);
vp9_copy(cpi->mb.nmvcosts, cc->nmvcosts);
vp9_copy(cpi->mb.nmvcosts_hp, cc->nmvcosts_hp);
vp9_copy(cm->seg.pred_probs, cc->segment_pred_probs);
vpx_memcpy(cm->last_frame_seg_map,
cpi->coding_context.last_frame_seg_map_copy,
(cm->mi_rows * cm->mi_cols));
vp9_copy(cm->lf.last_ref_deltas, cc->last_ref_lf_deltas);
vp9_copy(cm->lf.last_mode_deltas, cc->last_mode_lf_deltas);
cm->fc = cc->fc;
}
void vp9_setup_key_frame(VP9_COMP *cpi) {
VP9_COMMON *cm = &cpi->common;
vp9_setup_past_independence(cm);
/* All buffers are implicitly updated on key frames. */
cpi->refresh_golden_frame = 1;
cpi->refresh_alt_ref_frame = 1;
}
void vp9_setup_inter_frame(VP9_COMP *cpi) {
VP9_COMMON *cm = &cpi->common;
if (cm->error_resilient_mode || cm->intra_only)
vp9_setup_past_independence(cm);
assert(cm->frame_context_idx < FRAME_CONTEXTS);
cm->fc = cm->frame_contexts[cm->frame_context_idx];
}
static int estimate_bits_at_q(int frame_kind, int q, int mbs,
double correction_factor) {
const int bpm = (int)(vp9_rc_bits_per_mb(frame_kind, q, correction_factor));
// Attempt to retain reasonable accuracy without overflow. The cutoff is
// chosen such that the maximum product of Bpm and MBs fits 31 bits. The
// largest Bpm takes 20 bits.
return (mbs > (1 << 11)) ? (bpm >> BPER_MB_NORMBITS) * mbs
: (bpm * mbs) >> BPER_MB_NORMBITS;
}
static void calc_iframe_target_size(VP9_COMP *cpi) {
const VP9_CONFIG *oxcf = &cpi->oxcf;
RATE_CONTROL *const rc = &cpi->rc;
int target;
vp9_clear_system_state(); // __asm emms;
// For 1-pass.
if (cpi->pass == 0 && oxcf->end_usage == USAGE_STREAM_FROM_SERVER) {
if (cpi->common.current_video_frame == 0) {
target = oxcf->starting_buffer_level / 2;
} else {
// TODO(marpan): Add in adjustment based on Q.
// If this keyframe was forced, use a more recent Q estimate.
// int Q = (cpi->common.frame_flags & FRAMEFLAGS_KEY) ?
// cpi->rc.avg_frame_qindex : cpi->rc.ni_av_qi;
int initial_boost = 32;
// Boost depends somewhat on frame rate.
int kf_boost = MAX(initial_boost, (int)(2 * cpi->output_framerate - 16));
// Adjustment up based on q: need to fix.
// kf_boost = kf_boost * kfboost_qadjust(Q) / 100;
// Frame separation adjustment (down).
if (rc->frames_since_key < cpi->output_framerate / 2) {
kf_boost = (int)(kf_boost * rc->frames_since_key /
(cpi->output_framerate / 2));
}
kf_boost = (kf_boost < 16) ? 16 : kf_boost;
target = ((16 + kf_boost) * rc->per_frame_bandwidth) >> 4;
}
rc->active_worst_quality = rc->worst_quality;
} else {
target = rc->per_frame_bandwidth;
}
if (oxcf->rc_max_intra_bitrate_pct) {
const int max_rate = rc->per_frame_bandwidth *
oxcf->rc_max_intra_bitrate_pct / 100;
target = MIN(target, max_rate);
}
rc->this_frame_target = target;
}
// Update the buffer level: leaky bucket model.
void vp9_update_buffer_level(VP9_COMP *const cpi, int encoded_frame_size) {
const VP9_COMMON *const cm = &cpi->common;
const VP9_CONFIG *oxcf = &cpi->oxcf;
RATE_CONTROL *const rc = &cpi->rc;
// Non-viewable frames are a special case and are treated as pure overhead.
if (!cm->show_frame) {
rc->bits_off_target -= encoded_frame_size;
} else {
rc->bits_off_target += rc->av_per_frame_bandwidth - encoded_frame_size;
}
// Clip the buffer level to the maximum specified buffer size.
rc->buffer_level = MIN(rc->bits_off_target, oxcf->maximum_buffer_size);
}
int vp9_drop_frame(VP9_COMP *const cpi) {
const VP9_CONFIG *oxcf = &cpi->oxcf;
RATE_CONTROL *const rc = &cpi->rc;
if (!oxcf->drop_frames_water_mark) {
return 0;
} else {
if (rc->buffer_level < 0) {
// Always drop if buffer is below 0.
return 1;
} else {
// If buffer is below drop_mark, for now just drop every other frame
// (starting with the next frame) until it increases back over drop_mark.
int drop_mark = (int)(oxcf->drop_frames_water_mark *
oxcf->optimal_buffer_level / 100);
if ((rc->buffer_level > drop_mark) &&
(rc->decimation_factor > 0)) {
--rc->decimation_factor;
} else if (rc->buffer_level <= drop_mark &&
rc->decimation_factor == 0) {
rc->decimation_factor = 1;
}
if (rc->decimation_factor > 0) {
if (rc->decimation_count > 0) {
--rc->decimation_count;
return 1;
} else {
rc->decimation_count = rc->decimation_factor;
return 0;
}
} else {
rc->decimation_count = 0;
return 0;
}
}
}
}
// Adjust active_worst_quality level based on buffer level.
static int adjust_active_worst_quality_from_buffer_level(const VP9_CONFIG *oxcf,
const RATE_CONTROL *rc) {
// Adjust active_worst_quality: If buffer is above the optimal/target level,
// bring active_worst_quality down depending on fullness over buffer.
// If buffer is below the optimal level, let the active_worst_quality go from
// ambient Q (at buffer = optimal level) to worst_quality level
// (at buffer = critical level).
int active_worst_quality = rc->active_worst_quality;
// Maximum limit for down adjustment, ~20%.
int max_adjustment_down = active_worst_quality / 5;
// Buffer level below which we push active_worst to worst_quality.
int critical_level = oxcf->optimal_buffer_level >> 2;
int adjustment = 0;
int buff_lvl_step = 0;
if (rc->buffer_level > oxcf->optimal_buffer_level) {
// Adjust down.
if (max_adjustment_down) {
buff_lvl_step = (int)((oxcf->maximum_buffer_size -
oxcf->optimal_buffer_level) / max_adjustment_down);
if (buff_lvl_step)
adjustment = (int)((rc->buffer_level - oxcf->optimal_buffer_level) /
buff_lvl_step);
active_worst_quality -= adjustment;
}
} else if (rc->buffer_level > critical_level) {
// Adjust up from ambient Q.
if (critical_level) {
buff_lvl_step = (oxcf->optimal_buffer_level - critical_level);
if (buff_lvl_step) {
adjustment = (rc->worst_quality - rc->avg_frame_qindex[INTER_FRAME]) *
(oxcf->optimal_buffer_level - rc->buffer_level) /
buff_lvl_step;
}
active_worst_quality = rc->avg_frame_qindex[INTER_FRAME] + adjustment;
}
} else {
// Set to worst_quality if buffer is below critical level.
active_worst_quality = rc->worst_quality;
}
return active_worst_quality;
}
// Adjust target frame size with respect to the buffering constraints:
static int target_size_from_buffer_level(const VP9_CONFIG *oxcf,
const RATE_CONTROL *rc) {
int target = rc->this_frame_target;
const int64_t diff = oxcf->optimal_buffer_level - rc->buffer_level;
const int one_pct_bits = 1 + oxcf->optimal_buffer_level / 100;
if (diff > 0) {
// Lower the target bandwidth for this frame.
const int pct_low = MIN(diff / one_pct_bits, oxcf->under_shoot_pct);
target -= (target * pct_low) / 200;
} else if (diff < 0) {
// Increase the target bandwidth for this frame.
const int pct_high = MIN(-diff / one_pct_bits, oxcf->over_shoot_pct);
target += (target * pct_high) / 200;
}
return target;
}
static void calc_pframe_target_size(VP9_COMP *const cpi) {
RATE_CONTROL *const rc = &cpi->rc;
const VP9_CONFIG *const oxcf = &cpi->oxcf;
int min_frame_target;
rc->this_frame_target = rc->per_frame_bandwidth;
if (cpi->pass == 0 && oxcf->end_usage == USAGE_STREAM_FROM_SERVER) {
// Need to decide how low min_frame_target should be for 1-pass CBR.
// For now, use: cpi->rc.av_per_frame_bandwidth / 16:
min_frame_target = MAX(rc->av_per_frame_bandwidth >> 4,
FRAME_OVERHEAD_BITS);
rc->this_frame_target = target_size_from_buffer_level(oxcf, rc);
// Adjust qp-max based on buffer level.
rc->active_worst_quality =
adjust_active_worst_quality_from_buffer_level(oxcf, rc);
if (rc->this_frame_target < min_frame_target)
rc->this_frame_target = min_frame_target;
return;
}
// Check that the total sum of adjustments is not above the maximum allowed.
// That is, having allowed for the KF and GF penalties, we have not pushed
// the current inter-frame target too low. If the adjustment we apply here is
// not capable of recovering all the extra bits we have spent in the KF or GF,
// then the remainder will have to be recovered over a longer time span via
// other buffer / rate control mechanisms.
min_frame_target = MAX(rc->min_frame_bandwidth,
rc->av_per_frame_bandwidth >> 5);
if (rc->this_frame_target < min_frame_target)
rc->this_frame_target = min_frame_target;
// Adjust target frame size for Golden Frames:
if (cpi->refresh_golden_frame) {
// If we are using alternate ref instead of gf then do not apply the boost
// It will instead be applied to the altref update
// Jims modified boost
if (!rc->source_alt_ref_active) {
// The spend on the GF is defined in the two pass code
// for two pass encodes
rc->this_frame_target = rc->per_frame_bandwidth;
} else {
// If there is an active ARF at this location use the minimum
// bits on this frame even if it is a constructed arf.
// The active maximum quantizer insures that an appropriate
// number of bits will be spent if needed for constructed ARFs.
rc->this_frame_target = 0;
}
}
}
static double get_rate_correction_factor(const VP9_COMP *cpi) {
if (cpi->common.frame_type == KEY_FRAME) {
return cpi->rc.key_frame_rate_correction_factor;
} else {
if (cpi->refresh_alt_ref_frame || cpi->refresh_golden_frame)
return cpi->rc.gf_rate_correction_factor;
else
return cpi->rc.rate_correction_factor;
}
}
static void set_rate_correction_factor(VP9_COMP *cpi, double factor) {
if (cpi->common.frame_type == KEY_FRAME) {
cpi->rc.key_frame_rate_correction_factor = factor;
} else {
if (cpi->refresh_alt_ref_frame || cpi->refresh_golden_frame)
cpi->rc.gf_rate_correction_factor = factor;
else
cpi->rc.rate_correction_factor = factor;
}
}
void vp9_rc_update_rate_correction_factors(VP9_COMP *cpi, int damp_var) {
const int q = cpi->common.base_qindex;
int correction_factor = 100;
double rate_correction_factor = get_rate_correction_factor(cpi);
double adjustment_limit;
int projected_size_based_on_q = 0;
// Clear down mmx registers to allow floating point in what follows
vp9_clear_system_state(); // __asm emms;
// Work out how big we would have expected the frame to be at this Q given
// the current correction factor.
// Stay in double to avoid int overflow when values are large
projected_size_based_on_q = estimate_bits_at_q(cpi->common.frame_type, q,
cpi->common.MBs,
rate_correction_factor);
// Work out a size correction factor.
if (projected_size_based_on_q > 0)
correction_factor = (100 * cpi->rc.projected_frame_size) /
projected_size_based_on_q;
// More heavily damped adjustment used if we have been oscillating either side
// of target.
switch (damp_var) {
case 0:
adjustment_limit = 0.75;
break;
case 1:
adjustment_limit = 0.375;
break;
case 2:
default:
adjustment_limit = 0.25;
break;
}
if (correction_factor > 102) {
// We are not already at the worst allowable quality
correction_factor =
(int)(100 + ((correction_factor - 100) * adjustment_limit));
rate_correction_factor =
((rate_correction_factor * correction_factor) / 100);
// Keep rate_correction_factor within limits
if (rate_correction_factor > MAX_BPB_FACTOR)
rate_correction_factor = MAX_BPB_FACTOR;
} else if (correction_factor < 99) {
// We are not already at the best allowable quality
correction_factor =
(int)(100 - ((100 - correction_factor) * adjustment_limit));
rate_correction_factor =
((rate_correction_factor * correction_factor) / 100);
// Keep rate_correction_factor within limits
if (rate_correction_factor < MIN_BPB_FACTOR)
rate_correction_factor = MIN_BPB_FACTOR;
}
set_rate_correction_factor(cpi, rate_correction_factor);
}
int vp9_rc_regulate_q(const VP9_COMP *cpi, int target_bits_per_frame,
int active_best_quality, int active_worst_quality) {
const VP9_COMMON *const cm = &cpi->common;
int q = active_worst_quality;
int last_error = INT_MAX;
int i, target_bits_per_mb;
const double correction_factor = get_rate_correction_factor(cpi);
// Calculate required scaling factor based on target frame size and size of
// frame produced using previous Q.
if (target_bits_per_frame >= (INT_MAX >> BPER_MB_NORMBITS))
// Case where we would overflow int
target_bits_per_mb = (target_bits_per_frame / cm->MBs) << BPER_MB_NORMBITS;
else
target_bits_per_mb = (target_bits_per_frame << BPER_MB_NORMBITS) / cm->MBs;
i = active_best_quality;
do {
const int bits_per_mb_at_this_q = (int)vp9_rc_bits_per_mb(cm->frame_type, i,
correction_factor);
if (bits_per_mb_at_this_q <= target_bits_per_mb) {
if ((target_bits_per_mb - bits_per_mb_at_this_q) <= last_error)
q = i;
else
q = i - 1;
break;
} else {
last_error = bits_per_mb_at_this_q - target_bits_per_mb;
}
} while (++i <= active_worst_quality);
return q;
}
static int get_active_quality(int q, int gfu_boost, int low, int high,
int *low_motion_minq, int *high_motion_minq) {
if (gfu_boost > high) {
return low_motion_minq[q];
} else if (gfu_boost < low) {
return high_motion_minq[q];
} else {
const int gap = high - low;
const int offset = high - gfu_boost;
const int qdiff = high_motion_minq[q] - low_motion_minq[q];
const int adjustment = ((offset * qdiff) + (gap >> 1)) / gap;
return low_motion_minq[q] + adjustment;
}
}
int vp9_rc_pick_q_and_adjust_q_bounds(const VP9_COMP *cpi,
int *bottom_index, int *top_index) {
const VP9_COMMON *const cm = &cpi->common;
const RATE_CONTROL *const rc = &cpi->rc;
const VP9_CONFIG *const oxcf = &cpi->oxcf;
int active_best_quality;
int active_worst_quality = rc->active_worst_quality;
int q;
if (frame_is_intra_only(cm)) {
active_best_quality = rc->best_quality;
#if !CONFIG_MULTIPLE_ARF
// Handle the special case for key frames forced when we have75 reached
// the maximum key frame interval. Here force the Q to a range
// based on the ambient Q to reduce the risk of popping.
if (rc->this_key_frame_forced) {
int qindex = rc->last_boosted_qindex;
double last_boosted_q = vp9_convert_qindex_to_q(qindex);
int delta_qindex = vp9_compute_qdelta(cpi, last_boosted_q,
(last_boosted_q * 0.75));
active_best_quality = MAX(qindex + delta_qindex, rc->best_quality);
} else if (!(cpi->pass == 0 && cm->current_video_frame == 0)) {
// not first frame of one pass and kf_boost is set
double q_adj_factor = 1.0;
double q_val;
// Baseline value derived from cpi->active_worst_quality and kf boost
active_best_quality = get_active_quality(active_worst_quality,
rc->kf_boost,
kf_low, kf_high,
kf_low_motion_minq,
kf_high_motion_minq);
// Allow somewhat lower kf minq with small image formats.
if ((cm->width * cm->height) <= (352 * 288)) {
q_adj_factor -= 0.25;
}
// Make a further adjustment based on the kf zero motion measure.
q_adj_factor += 0.05 - (0.001 * (double)cpi->twopass.kf_zeromotion_pct);
// Convert the adjustment factor to a qindex delta
// on active_best_quality.
q_val = vp9_convert_qindex_to_q(active_best_quality);
active_best_quality += vp9_compute_qdelta(cpi, q_val, q_val *
q_adj_factor);
}
#else
double current_q;
// Force the KF quantizer to be 30% of the active_worst_quality.
current_q = vp9_convert_qindex_to_q(active_worst_quality);
active_best_quality = active_worst_quality
+ vp9_compute_qdelta(cpi, current_q, current_q * 0.3);
#endif
} else if (!rc->is_src_frame_alt_ref &&
(cpi->refresh_golden_frame || cpi->refresh_alt_ref_frame)) {
// Use the lower of active_worst_quality and recent
// average Q as basis for GF/ARF best Q limit unless last frame was
// a key frame.
if (rc->frames_since_key > 1 &&
rc->avg_frame_qindex[INTER_FRAME] < active_worst_quality) {
q = rc->avg_frame_qindex[INTER_FRAME];
} else {
q = active_worst_quality;
}
// For constrained quality dont allow Q less than the cq level
if (oxcf->end_usage == USAGE_CONSTRAINED_QUALITY) {
if (q < cpi->cq_target_quality)
q = cpi->cq_target_quality;
if (rc->frames_since_key > 1) {
active_best_quality = get_active_quality(q, rc->gfu_boost,
gf_low, gf_high,
afq_low_motion_minq,
afq_high_motion_minq);
} else {
active_best_quality = get_active_quality(q, rc->gfu_boost,
gf_low, gf_high,
gf_low_motion_minq,
gf_high_motion_minq);
}
// Constrained quality use slightly lower active best.
active_best_quality = active_best_quality * 15 / 16;
} else if (oxcf->end_usage == USAGE_CONSTANT_QUALITY) {
if (!cpi->refresh_alt_ref_frame) {
active_best_quality = cpi->cq_target_quality;
} else {
if (rc->frames_since_key > 1) {
active_best_quality = get_active_quality(
q, rc->gfu_boost, gf_low, gf_high,
afq_low_motion_minq, afq_high_motion_minq);
} else {
active_best_quality = get_active_quality(
q, rc->gfu_boost, gf_low, gf_high,
gf_low_motion_minq, gf_high_motion_minq);
}
}
} else {
active_best_quality = get_active_quality(
q, rc->gfu_boost, gf_low, gf_high,
gf_low_motion_minq, gf_high_motion_minq);
}
} else {
if (oxcf->end_usage == USAGE_CONSTANT_QUALITY) {
active_best_quality = cpi->cq_target_quality;
} else {
if (cpi->pass == 0 &&
rc->avg_frame_qindex[INTER_FRAME] < active_worst_quality)
// 1-pass: for now, use the average Q for the active_best, if its lower
// than active_worst.
active_best_quality = inter_minq[rc->avg_frame_qindex[INTER_FRAME]];
else
active_best_quality = inter_minq[active_worst_quality];
// For the constrained quality mode we don't want
// q to fall below the cq level.
if ((oxcf->end_usage == USAGE_CONSTRAINED_QUALITY) &&
(active_best_quality < cpi->cq_target_quality)) {
// If we are strongly undershooting the target rate in the last
// frames then use the user passed in cq value not the auto
// cq value.
if (rc->rolling_actual_bits < rc->min_frame_bandwidth)
active_best_quality = oxcf->cq_level;
else
active_best_quality = cpi->cq_target_quality;
}
}
}
// Clip the active best and worst quality values to limits
if (active_worst_quality > rc->worst_quality)
active_worst_quality = rc->worst_quality;
if (active_best_quality < rc->best_quality)
active_best_quality = rc->best_quality;
if (active_best_quality > rc->worst_quality)
active_best_quality = rc->worst_quality;
if (active_worst_quality < active_best_quality)
active_worst_quality = active_best_quality;
*top_index = active_worst_quality;
*bottom_index = active_best_quality;
#if LIMIT_QRANGE_FOR_ALTREF_AND_KEY
// Limit Q range for the adaptive loop.
if (cm->frame_type == KEY_FRAME && !rc->this_key_frame_forced) {
if (!(cpi->pass == 0 && cm->current_video_frame == 0))
*top_index = (active_worst_quality + active_best_quality * 3) / 4;
} else if (!rc->is_src_frame_alt_ref &&
(oxcf->end_usage != USAGE_STREAM_FROM_SERVER) &&
(cpi->refresh_golden_frame || cpi->refresh_alt_ref_frame)) {
*top_index = (active_worst_quality + active_best_quality) / 2;
}
#endif
if (oxcf->end_usage == USAGE_CONSTANT_QUALITY) {
q = active_best_quality;
// Special case code to try and match quality with forced key frames
} else if ((cm->frame_type == KEY_FRAME) && rc->this_key_frame_forced) {
q = rc->last_boosted_qindex;
} else {
q = vp9_rc_regulate_q(cpi, rc->this_frame_target,
active_best_quality, active_worst_quality);
if (q > *top_index) {
// Special case when we are targeting the max allowed rate
if (cpi->rc.this_frame_target >= cpi->rc.max_frame_bandwidth)
*top_index = q;
else
q = *top_index;
}
}
#if CONFIG_MULTIPLE_ARF
// Force the quantizer determined by the coding order pattern.
if (cpi->multi_arf_enabled && (cm->frame_type != KEY_FRAME) &&
cpi->oxcf.end_usage != USAGE_CONSTANT_QUALITY) {
double new_q;
double current_q = vp9_convert_qindex_to_q(active_worst_quality);
int level = cpi->this_frame_weight;
assert(level >= 0);
new_q = current_q * (1.0 - (0.2 * (cpi->max_arf_level - level)));
q = active_worst_quality +
vp9_compute_qdelta(cpi, current_q, new_q);
*bottom_index = q;
*top_index = q;
printf("frame:%d q:%d\n", cm->current_video_frame, q);
}
#endif
assert(*top_index <= rc->worst_quality &&
*top_index >= rc->best_quality);
assert(*bottom_index <= rc->worst_quality &&
*bottom_index >= rc->best_quality);
assert(q <= rc->worst_quality && q >= rc->best_quality);
return q;
}
void vp9_rc_compute_frame_size_bounds(const VP9_COMP *cpi,
int this_frame_target,
int *frame_under_shoot_limit,
int *frame_over_shoot_limit) {
// Set-up bounds on acceptable frame size:
if (cpi->oxcf.end_usage == USAGE_CONSTANT_QUALITY) {
*frame_under_shoot_limit = 0;
*frame_over_shoot_limit = INT_MAX;
} else {
if (cpi->common.frame_type == KEY_FRAME) {
*frame_over_shoot_limit = this_frame_target * 9 / 8;
*frame_under_shoot_limit = this_frame_target * 7 / 8;
} else {
if (cpi->refresh_alt_ref_frame || cpi->refresh_golden_frame) {
*frame_over_shoot_limit = this_frame_target * 9 / 8;
*frame_under_shoot_limit = this_frame_target * 7 / 8;
} else {
// Stron overshoot limit for constrained quality
if (cpi->oxcf.end_usage == USAGE_CONSTRAINED_QUALITY) {
*frame_over_shoot_limit = this_frame_target * 11 / 8;
*frame_under_shoot_limit = this_frame_target * 2 / 8;
} else {
*frame_over_shoot_limit = this_frame_target * 11 / 8;
*frame_under_shoot_limit = this_frame_target * 5 / 8;
}
}
}
// For very small rate targets where the fractional adjustment
// (eg * 7/8) may be tiny make sure there is at least a minimum
// range.
*frame_over_shoot_limit += 200;
*frame_under_shoot_limit -= 200;
if (*frame_under_shoot_limit < 0)
*frame_under_shoot_limit = 0;
// Clip to maximum allowed rate for a frame.
if (*frame_over_shoot_limit > cpi->rc.max_frame_bandwidth) {
*frame_over_shoot_limit = cpi->rc.max_frame_bandwidth;
}
}
}
// return of 0 means drop frame
int vp9_rc_pick_frame_size_target(VP9_COMP *cpi) {
const VP9_COMMON *const cm = &cpi->common;
RATE_CONTROL *const rc = &cpi->rc;
if (cm->frame_type == KEY_FRAME)
calc_iframe_target_size(cpi);
else
calc_pframe_target_size(cpi);
// Clip the frame target to the maximum allowed value.
if (rc->this_frame_target > rc->max_frame_bandwidth)
rc->this_frame_target = rc->max_frame_bandwidth;
// Target rate per SB64 (including partial SB64s.
rc->sb64_target_rate = ((int64_t)rc->this_frame_target * 64 * 64) /
(cm->width * cm->height);
return 1;
}
static void update_alt_ref_frame_stats(VP9_COMP *cpi) {
// this frame refreshes means next frames don't unless specified by user
cpi->rc.frames_since_golden = 0;
#if CONFIG_MULTIPLE_ARF
if (!cpi->multi_arf_enabled)
#endif
// Clear the alternate reference update pending flag.
cpi->rc.source_alt_ref_pending = 0;
// Set the alternate reference frame active flag
cpi->rc.source_alt_ref_active = 1;
}
static void update_golden_frame_stats(VP9_COMP *cpi) {
RATE_CONTROL *const rc = &cpi->rc;
// Update the Golden frame usage counts.
if (cpi->refresh_golden_frame) {
// this frame refreshes means next frames don't unless specified by user
rc->frames_since_golden = 0;
if (!rc->source_alt_ref_pending)
rc->source_alt_ref_active = 0;
// Decrement count down till next gf
if (rc->frames_till_gf_update_due > 0)
rc->frames_till_gf_update_due--;
} else if (!cpi->refresh_alt_ref_frame) {
// Decrement count down till next gf
if (rc->frames_till_gf_update_due > 0)
rc->frames_till_gf_update_due--;
rc->frames_since_golden++;
}
}
void vp9_rc_postencode_update(VP9_COMP *cpi, uint64_t bytes_used) {
VP9_COMMON *const cm = &cpi->common;
RATE_CONTROL *const rc = &cpi->rc;
// Update rate control heuristics
rc->projected_frame_size = (bytes_used << 3);
// Post encode loop adjustment of Q prediction.
vp9_rc_update_rate_correction_factors(cpi, (cpi->sf.recode_loop ||
cpi->oxcf.end_usage == USAGE_STREAM_FROM_SERVER) ? 2 : 0);
// Keep a record of last Q and ambient average Q.
if (cm->frame_type == KEY_FRAME) {
rc->last_q[KEY_FRAME] = cm->base_qindex;
rc->avg_frame_qindex[KEY_FRAME] = ROUND_POWER_OF_TWO(
3 * rc->avg_frame_qindex[KEY_FRAME] + cm->base_qindex, 2);
} else if (!rc->is_src_frame_alt_ref &&
(cpi->refresh_golden_frame || cpi->refresh_alt_ref_frame)) {
rc->last_q[2] = cm->base_qindex;
rc->avg_frame_qindex[2] = ROUND_POWER_OF_TWO(
3 * rc->avg_frame_qindex[2] + cm->base_qindex, 2);
} else {
rc->last_q[INTER_FRAME] = cm->base_qindex;
rc->avg_frame_qindex[INTER_FRAME] = ROUND_POWER_OF_TWO(
3 * rc->avg_frame_qindex[INTER_FRAME] + cm->base_qindex, 2);
rc->ni_frames++;
rc->tot_q += vp9_convert_qindex_to_q(cm->base_qindex);
rc->avg_q = rc->tot_q / (double)rc->ni_frames;
// Calculate the average Q for normal inter frames (not key or GFU frames).
rc->ni_tot_qi += cm->base_qindex;
rc->ni_av_qi = rc->ni_tot_qi / rc->ni_frames;
}
// Keep record of last boosted (KF/KF/ARF) Q value.
// If the current frame is coded at a lower Q then we also update it.
// If all mbs in this group are skipped only update if the Q value is
// better than that already stored.
// This is used to help set quality in forced key frames to reduce popping
if ((cm->base_qindex < rc->last_boosted_qindex) ||
((cpi->static_mb_pct < 100) &&
((cm->frame_type == KEY_FRAME) || cpi->refresh_alt_ref_frame ||
(cpi->refresh_golden_frame && !rc->is_src_frame_alt_ref)))) {
rc->last_boosted_qindex = cm->base_qindex;
}
vp9_update_buffer_level(cpi, rc->projected_frame_size);
// Rolling monitors of whether we are over or underspending used to help
// regulate min and Max Q in two pass.
if (cm->frame_type != KEY_FRAME) {
rc->rolling_target_bits = ROUND_POWER_OF_TWO(
rc->rolling_target_bits * 3 + rc->this_frame_target, 2);
rc->rolling_actual_bits = ROUND_POWER_OF_TWO(
rc->rolling_actual_bits * 3 + rc->projected_frame_size, 2);
rc->long_rolling_target_bits = ROUND_POWER_OF_TWO(
rc->long_rolling_target_bits * 31 + rc->this_frame_target, 5);
rc->long_rolling_actual_bits = ROUND_POWER_OF_TWO(
rc->long_rolling_actual_bits * 31 + rc->projected_frame_size, 5);
}
// Actual bits spent
rc->total_actual_bits += rc->projected_frame_size;
// Debug stats
rc->total_target_vs_actual += (rc->this_frame_target -
rc->projected_frame_size);
#ifndef DISABLE_RC_LONG_TERM_MEM
// Update bits left to the kf and gf groups to account for overshoot or
// undershoot on these frames
if (cm->frame_type == KEY_FRAME) {
cpi->twopass.kf_group_bits += cpi->rc.this_frame_target -
cpi->rc.projected_frame_size;
cpi->twopass.kf_group_bits = MAX(cpi->twopass.kf_group_bits, 0);
} else if (cpi->refresh_golden_frame || cpi->refresh_alt_ref_frame) {
cpi->twopass.gf_group_bits += cpi->rc.this_frame_target -
cpi->rc.projected_frame_size;
cpi->twopass.gf_group_bits = MAX(cpi->twopass.gf_group_bits, 0);
}
#endif
if (cpi->oxcf.play_alternate && cpi->refresh_alt_ref_frame &&
(cm->frame_type != KEY_FRAME))
// Update the alternate reference frame stats as appropriate.
update_alt_ref_frame_stats(cpi);
else
// Update the Golden frame stats as appropriate.
update_golden_frame_stats(cpi);
if (cm->frame_type == KEY_FRAME)
rc->frames_since_key = 0;
if (cm->show_frame) {
rc->frames_since_key++;
rc->frames_to_key--;
}
}
void vp9_rc_postencode_update_drop_frame(VP9_COMP *cpi) {
cpi->rc.frames_since_key++;
cpi->rc.frames_to_key--;
}