ref: fa472129334e197f0a977fd8ccd0bf2a145d0935
dir: /vp10/encoder/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 <assert.h>
#include <limits.h>
#include <math.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include "vpx_mem/vpx_mem.h"
#include "vpx_ports/mem.h"
#include "vpx_ports/system_state.h"
#include "vp10/common/alloccommon.h"
#include "vp10/encoder/aq_cyclicrefresh.h"
#include "vp10/common/common.h"
#include "vp10/common/entropymode.h"
#include "vp10/common/quant_common.h"
#include "vp10/common/seg_common.h"
#include "vp10/encoder/encodemv.h"
#include "vp10/encoder/ratectrl.h"
// Max rate target for 1080P and below encodes under normal circumstances
// (1920 * 1080 / (16 * 16)) * MAX_MB_RATE bits per MB
#define MAX_MB_RATE 250
#define MAXRATE_1080P 2025000
#define DEFAULT_KF_BOOST 2000
#define DEFAULT_GF_BOOST 2000
#define LIMIT_QRANGE_FOR_ALTREF_AND_KEY 1
#define MIN_BPB_FACTOR 0.005
#define MAX_BPB_FACTOR 50
#define FRAME_OVERHEAD_BITS 200
#if CONFIG_VP9_HIGHBITDEPTH
#define ASSIGN_MINQ_TABLE(bit_depth, name) \
do { \
switch (bit_depth) { \
case VPX_BITS_8: \
name = name##_8; \
break; \
case VPX_BITS_10: \
name = name##_10; \
break; \
case VPX_BITS_12: \
name = name##_12; \
break; \
default: \
assert(0 && "bit_depth should be VPX_BITS_8, VPX_BITS_10" \
" or VPX_BITS_12"); \
name = NULL; \
} \
} while (0)
#else
#define ASSIGN_MINQ_TABLE(bit_depth, name) \
do { \
(void) bit_depth; \
name = name##_8; \
} while (0)
#endif
// Tables relating active max Q to active min Q
static int kf_low_motion_minq_8[QINDEX_RANGE];
static int kf_high_motion_minq_8[QINDEX_RANGE];
static int arfgf_low_motion_minq_8[QINDEX_RANGE];
static int arfgf_high_motion_minq_8[QINDEX_RANGE];
static int inter_minq_8[QINDEX_RANGE];
static int rtc_minq_8[QINDEX_RANGE];
#if CONFIG_VP9_HIGHBITDEPTH
static int kf_low_motion_minq_10[QINDEX_RANGE];
static int kf_high_motion_minq_10[QINDEX_RANGE];
static int arfgf_low_motion_minq_10[QINDEX_RANGE];
static int arfgf_high_motion_minq_10[QINDEX_RANGE];
static int inter_minq_10[QINDEX_RANGE];
static int rtc_minq_10[QINDEX_RANGE];
static int kf_low_motion_minq_12[QINDEX_RANGE];
static int kf_high_motion_minq_12[QINDEX_RANGE];
static int arfgf_low_motion_minq_12[QINDEX_RANGE];
static int arfgf_high_motion_minq_12[QINDEX_RANGE];
static int inter_minq_12[QINDEX_RANGE];
static int rtc_minq_12[QINDEX_RANGE];
#endif
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 get_minq_index(double maxq, double x3, double x2, double x1,
vpx_bit_depth_t bit_depth) {
int i;
const double minqtarget = MIN(((x3 * maxq + x2) * maxq + x1) * maxq,
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 <= vp10_convert_qindex_to_q(i, bit_depth))
return i;
}
return QINDEX_RANGE - 1;
}
static void init_minq_luts(int *kf_low_m, int *kf_high_m,
int *arfgf_low, int *arfgf_high,
int *inter, int *rtc, vpx_bit_depth_t bit_depth) {
int i;
for (i = 0; i < QINDEX_RANGE; i++) {
const double maxq = vp10_convert_qindex_to_q(i, bit_depth);
kf_low_m[i] = get_minq_index(maxq, 0.000001, -0.0004, 0.150, bit_depth);
kf_high_m[i] = get_minq_index(maxq, 0.0000021, -0.00125, 0.55, bit_depth);
arfgf_low[i] = get_minq_index(maxq, 0.0000015, -0.0009, 0.30, bit_depth);
arfgf_high[i] = get_minq_index(maxq, 0.0000021, -0.00125, 0.55, bit_depth);
inter[i] = get_minq_index(maxq, 0.00000271, -0.00113, 0.90, bit_depth);
rtc[i] = get_minq_index(maxq, 0.00000271, -0.00113, 0.70, bit_depth);
}
}
void vp10_rc_init_minq_luts(void) {
init_minq_luts(kf_low_motion_minq_8, kf_high_motion_minq_8,
arfgf_low_motion_minq_8, arfgf_high_motion_minq_8,
inter_minq_8, rtc_minq_8, VPX_BITS_8);
#if CONFIG_VP9_HIGHBITDEPTH
init_minq_luts(kf_low_motion_minq_10, kf_high_motion_minq_10,
arfgf_low_motion_minq_10, arfgf_high_motion_minq_10,
inter_minq_10, rtc_minq_10, VPX_BITS_10);
init_minq_luts(kf_low_motion_minq_12, kf_high_motion_minq_12,
arfgf_low_motion_minq_12, arfgf_high_motion_minq_12,
inter_minq_12, rtc_minq_12, VPX_BITS_12);
#endif
}
// 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 vp10_convert_qindex_to_q(int qindex, vpx_bit_depth_t bit_depth) {
// Convert the index to a real Q value (scaled down to match old Q values)
#if CONFIG_VP9_HIGHBITDEPTH
switch (bit_depth) {
case VPX_BITS_8:
return vp10_ac_quant(qindex, 0, bit_depth) / 4.0;
case VPX_BITS_10:
return vp10_ac_quant(qindex, 0, bit_depth) / 16.0;
case VPX_BITS_12:
return vp10_ac_quant(qindex, 0, bit_depth) / 64.0;
default:
assert(0 && "bit_depth should be VPX_BITS_8, VPX_BITS_10 or VPX_BITS_12");
return -1.0;
}
#else
return vp10_ac_quant(qindex, 0, bit_depth) / 4.0;
#endif
}
int vp10_rc_bits_per_mb(FRAME_TYPE frame_type, int qindex,
double correction_factor,
vpx_bit_depth_t bit_depth) {
const double q = vp10_convert_qindex_to_q(qindex, bit_depth);
int enumerator = frame_type == KEY_FRAME ? 2700000 : 1800000;
assert(correction_factor <= MAX_BPB_FACTOR &&
correction_factor >= MIN_BPB_FACTOR);
// q based adjustment to baseline enumerator
enumerator += (int)(enumerator * q) >> 12;
return (int)(enumerator * correction_factor / q);
}
int vp10_estimate_bits_at_q(FRAME_TYPE frame_type, int q, int mbs,
double correction_factor,
vpx_bit_depth_t bit_depth) {
const int bpm = (int)(vp10_rc_bits_per_mb(frame_type, q, correction_factor,
bit_depth));
return MAX(FRAME_OVERHEAD_BITS,
(int)((uint64_t)bpm * mbs) >> BPER_MB_NORMBITS);
}
int vp10_rc_clamp_pframe_target_size(const VP9_COMP *const cpi, int target) {
const RATE_CONTROL *rc = &cpi->rc;
const VP9EncoderConfig *oxcf = &cpi->oxcf;
const int min_frame_target = MAX(rc->min_frame_bandwidth,
rc->avg_frame_bandwidth >> 5);
if (target < min_frame_target)
target = min_frame_target;
if (cpi->refresh_golden_frame && rc->is_src_frame_alt_ref) {
// 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.
target = min_frame_target;
}
// Clip the frame target to the maximum allowed value.
if (target > rc->max_frame_bandwidth)
target = rc->max_frame_bandwidth;
if (oxcf->rc_max_inter_bitrate_pct) {
const int max_rate = rc->avg_frame_bandwidth *
oxcf->rc_max_inter_bitrate_pct / 100;
target = MIN(target, max_rate);
}
return target;
}
int vp10_rc_clamp_iframe_target_size(const VP9_COMP *const cpi, int target) {
const RATE_CONTROL *rc = &cpi->rc;
const VP9EncoderConfig *oxcf = &cpi->oxcf;
if (oxcf->rc_max_intra_bitrate_pct) {
const int max_rate = rc->avg_frame_bandwidth *
oxcf->rc_max_intra_bitrate_pct / 100;
target = MIN(target, max_rate);
}
if (target > rc->max_frame_bandwidth)
target = rc->max_frame_bandwidth;
return target;
}
// Update the buffer level for higher temporal layers, given the encoded current
// temporal layer.
static void update_layer_buffer_level(SVC *svc, int encoded_frame_size) {
int i = 0;
int current_temporal_layer = svc->temporal_layer_id;
for (i = current_temporal_layer + 1;
i < svc->number_temporal_layers; ++i) {
const int layer = LAYER_IDS_TO_IDX(svc->spatial_layer_id, i,
svc->number_temporal_layers);
LAYER_CONTEXT *lc = &svc->layer_context[layer];
RATE_CONTROL *lrc = &lc->rc;
int bits_off_for_this_layer = (int)(lc->target_bandwidth / lc->framerate -
encoded_frame_size);
lrc->bits_off_target += bits_off_for_this_layer;
// Clip buffer level to maximum buffer size for the layer.
lrc->bits_off_target = MIN(lrc->bits_off_target, lrc->maximum_buffer_size);
lrc->buffer_level = lrc->bits_off_target;
}
}
// Update the buffer level: leaky bucket model.
static void update_buffer_level(VP9_COMP *cpi, int encoded_frame_size) {
const VP9_COMMON *const cm = &cpi->common;
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->avg_frame_bandwidth - encoded_frame_size;
}
// Clip the buffer level to the maximum specified buffer size.
rc->bits_off_target = MIN(rc->bits_off_target, rc->maximum_buffer_size);
rc->buffer_level = rc->bits_off_target;
if (is_one_pass_cbr_svc(cpi)) {
update_layer_buffer_level(&cpi->svc, encoded_frame_size);
}
}
int vp10_rc_get_default_min_gf_interval(
int width, int height, double framerate) {
// Assume we do not need any constraint lower than 4K 20 fps
static const double factor_safe = 3840 * 2160 * 20.0;
const double factor = width * height * framerate;
const int default_interval =
clamp((int)(framerate * 0.125), MIN_GF_INTERVAL, MAX_GF_INTERVAL);
if (factor <= factor_safe)
return default_interval;
else
return MAX(default_interval,
(int)(MIN_GF_INTERVAL * factor / factor_safe + 0.5));
// Note this logic makes:
// 4K24: 5
// 4K30: 6
// 4K60: 12
}
int vp10_rc_get_default_max_gf_interval(double framerate, int min_gf_interval) {
int interval = MIN(MAX_GF_INTERVAL, (int)(framerate * 0.75));
interval += (interval & 0x01); // Round to even value
return MAX(interval, min_gf_interval);
}
void vp10_rc_init(const VP9EncoderConfig *oxcf, int pass, RATE_CONTROL *rc) {
int i;
if (pass == 0 && oxcf->rc_mode == VPX_CBR) {
rc->avg_frame_qindex[KEY_FRAME] = oxcf->worst_allowed_q;
rc->avg_frame_qindex[INTER_FRAME] = oxcf->worst_allowed_q;
} else {
rc->avg_frame_qindex[KEY_FRAME] = (oxcf->worst_allowed_q +
oxcf->best_allowed_q) / 2;
rc->avg_frame_qindex[INTER_FRAME] = (oxcf->worst_allowed_q +
oxcf->best_allowed_q) / 2;
}
rc->last_q[KEY_FRAME] = oxcf->best_allowed_q;
rc->last_q[INTER_FRAME] = oxcf->worst_allowed_q;
rc->buffer_level = rc->starting_buffer_level;
rc->bits_off_target = rc->starting_buffer_level;
rc->rolling_target_bits = rc->avg_frame_bandwidth;
rc->rolling_actual_bits = rc->avg_frame_bandwidth;
rc->long_rolling_target_bits = rc->avg_frame_bandwidth;
rc->long_rolling_actual_bits = rc->avg_frame_bandwidth;
rc->total_actual_bits = 0;
rc->total_target_bits = 0;
rc->total_target_vs_actual = 0;
rc->frames_since_key = 8; // Sensible default for first frame.
rc->this_key_frame_forced = 0;
rc->next_key_frame_forced = 0;
rc->source_alt_ref_pending = 0;
rc->source_alt_ref_active = 0;
rc->frames_till_gf_update_due = 0;
rc->ni_av_qi = oxcf->worst_allowed_q;
rc->ni_tot_qi = 0;
rc->ni_frames = 0;
rc->tot_q = 0.0;
rc->avg_q = vp10_convert_qindex_to_q(oxcf->worst_allowed_q, oxcf->bit_depth);
for (i = 0; i < RATE_FACTOR_LEVELS; ++i) {
rc->rate_correction_factors[i] = 1.0;
}
rc->min_gf_interval = oxcf->min_gf_interval;
rc->max_gf_interval = oxcf->max_gf_interval;
if (rc->min_gf_interval == 0)
rc->min_gf_interval = vp10_rc_get_default_min_gf_interval(
oxcf->width, oxcf->height, oxcf->init_framerate);
if (rc->max_gf_interval == 0)
rc->max_gf_interval = vp10_rc_get_default_max_gf_interval(
oxcf->init_framerate, rc->min_gf_interval);
rc->baseline_gf_interval = (rc->min_gf_interval + rc->max_gf_interval) / 2;
}
int vp10_rc_drop_frame(VP9_COMP *cpi) {
const VP9EncoderConfig *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 *
rc->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;
}
}
}
}
static double get_rate_correction_factor(const VP9_COMP *cpi) {
const RATE_CONTROL *const rc = &cpi->rc;
double rcf;
if (cpi->common.frame_type == KEY_FRAME) {
rcf = rc->rate_correction_factors[KF_STD];
} else if (cpi->oxcf.pass == 2) {
RATE_FACTOR_LEVEL rf_lvl =
cpi->twopass.gf_group.rf_level[cpi->twopass.gf_group.index];
rcf = rc->rate_correction_factors[rf_lvl];
} else {
if ((cpi->refresh_alt_ref_frame || cpi->refresh_golden_frame) &&
!rc->is_src_frame_alt_ref && !cpi->use_svc &&
(cpi->oxcf.rc_mode != VPX_CBR || cpi->oxcf.gf_cbr_boost_pct > 20))
rcf = rc->rate_correction_factors[GF_ARF_STD];
else
rcf = rc->rate_correction_factors[INTER_NORMAL];
}
rcf *= rcf_mult[rc->frame_size_selector];
return fclamp(rcf, MIN_BPB_FACTOR, MAX_BPB_FACTOR);
}
static void set_rate_correction_factor(VP9_COMP *cpi, double factor) {
RATE_CONTROL *const rc = &cpi->rc;
// Normalize RCF to account for the size-dependent scaling factor.
factor /= rcf_mult[cpi->rc.frame_size_selector];
factor = fclamp(factor, MIN_BPB_FACTOR, MAX_BPB_FACTOR);
if (cpi->common.frame_type == KEY_FRAME) {
rc->rate_correction_factors[KF_STD] = factor;
} else if (cpi->oxcf.pass == 2) {
RATE_FACTOR_LEVEL rf_lvl =
cpi->twopass.gf_group.rf_level[cpi->twopass.gf_group.index];
rc->rate_correction_factors[rf_lvl] = factor;
} else {
if ((cpi->refresh_alt_ref_frame || cpi->refresh_golden_frame) &&
!rc->is_src_frame_alt_ref && !cpi->use_svc &&
(cpi->oxcf.rc_mode != VPX_CBR || cpi->oxcf.gf_cbr_boost_pct > 20))
rc->rate_correction_factors[GF_ARF_STD] = factor;
else
rc->rate_correction_factors[INTER_NORMAL] = factor;
}
}
void vp10_rc_update_rate_correction_factors(VP9_COMP *cpi) {
const VP9_COMMON *const cm = &cpi->common;
int correction_factor = 100;
double rate_correction_factor = get_rate_correction_factor(cpi);
double adjustment_limit;
int projected_size_based_on_q = 0;
// Do not update the rate factors for arf overlay frames.
if (cpi->rc.is_src_frame_alt_ref)
return;
// Clear down mmx registers to allow floating point in what follows
vpx_clear_system_state();
// 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
if (cpi->oxcf.aq_mode == CYCLIC_REFRESH_AQ && cpi->common.seg.enabled) {
projected_size_based_on_q =
vp10_cyclic_refresh_estimate_bits_at_q(cpi, rate_correction_factor);
} else {
projected_size_based_on_q = vp10_estimate_bits_at_q(cpi->common.frame_type,
cm->base_qindex,
cm->MBs,
rate_correction_factor,
cm->bit_depth);
}
// Work out a size correction factor.
if (projected_size_based_on_q > FRAME_OVERHEAD_BITS)
correction_factor = (int)((100 * (int64_t)cpi->rc.projected_frame_size) /
projected_size_based_on_q);
// More heavily damped adjustment used if we have been oscillating either side
// of target.
adjustment_limit = 0.25 +
0.5 * MIN(1, fabs(log10(0.01 * correction_factor)));
cpi->rc.q_2_frame = cpi->rc.q_1_frame;
cpi->rc.q_1_frame = cm->base_qindex;
cpi->rc.rc_2_frame = cpi->rc.rc_1_frame;
if (correction_factor > 110)
cpi->rc.rc_1_frame = -1;
else if (correction_factor < 90)
cpi->rc.rc_1_frame = 1;
else
cpi->rc.rc_1_frame = 0;
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 vp10_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, bits_per_mb_at_this_q;
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.
target_bits_per_mb =
((uint64_t)target_bits_per_frame << BPER_MB_NORMBITS) / cm->MBs;
i = active_best_quality;
do {
if (cpi->oxcf.aq_mode == CYCLIC_REFRESH_AQ &&
cm->seg.enabled &&
cpi->svc.temporal_layer_id == 0 &&
cpi->svc.spatial_layer_id == 0) {
bits_per_mb_at_this_q =
(int)vp10_cyclic_refresh_rc_bits_per_mb(cpi, i, correction_factor);
} else {
bits_per_mb_at_this_q = (int)vp10_rc_bits_per_mb(cm->frame_type, i,
correction_factor,
cm->bit_depth);
}
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);
// In CBR mode, this makes sure q is between oscillating Qs to prevent
// resonance.
if (cpi->oxcf.rc_mode == VPX_CBR &&
(cpi->rc.rc_1_frame * cpi->rc.rc_2_frame == -1) &&
cpi->rc.q_1_frame != cpi->rc.q_2_frame) {
q = clamp(q, MIN(cpi->rc.q_1_frame, cpi->rc.q_2_frame),
MAX(cpi->rc.q_1_frame, cpi->rc.q_2_frame));
}
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;
}
}
static int get_kf_active_quality(const RATE_CONTROL *const rc, int q,
vpx_bit_depth_t bit_depth) {
int *kf_low_motion_minq;
int *kf_high_motion_minq;
ASSIGN_MINQ_TABLE(bit_depth, kf_low_motion_minq);
ASSIGN_MINQ_TABLE(bit_depth, kf_high_motion_minq);
return get_active_quality(q, rc->kf_boost, kf_low, kf_high,
kf_low_motion_minq, kf_high_motion_minq);
}
static int get_gf_active_quality(const RATE_CONTROL *const rc, int q,
vpx_bit_depth_t bit_depth) {
int *arfgf_low_motion_minq;
int *arfgf_high_motion_minq;
ASSIGN_MINQ_TABLE(bit_depth, arfgf_low_motion_minq);
ASSIGN_MINQ_TABLE(bit_depth, arfgf_high_motion_minq);
return get_active_quality(q, rc->gfu_boost, gf_low, gf_high,
arfgf_low_motion_minq, arfgf_high_motion_minq);
}
static int calc_active_worst_quality_one_pass_vbr(const VP9_COMP *cpi) {
const RATE_CONTROL *const rc = &cpi->rc;
const unsigned int curr_frame = cpi->common.current_video_frame;
int active_worst_quality;
if (cpi->common.frame_type == KEY_FRAME) {
active_worst_quality = curr_frame == 0 ? rc->worst_quality
: rc->last_q[KEY_FRAME] * 2;
} else {
if (!rc->is_src_frame_alt_ref &&
(cpi->refresh_golden_frame || cpi->refresh_alt_ref_frame)) {
active_worst_quality = curr_frame == 1 ? rc->last_q[KEY_FRAME] * 5 / 4
: rc->last_q[INTER_FRAME];
} else {
active_worst_quality = curr_frame == 1 ? rc->last_q[KEY_FRAME] * 2
: rc->last_q[INTER_FRAME] * 2;
}
}
return MIN(active_worst_quality, rc->worst_quality);
}
// Adjust active_worst_quality level based on buffer level.
static int calc_active_worst_quality_one_pass_cbr(const VP9_COMP *cpi) {
// Adjust active_worst_quality: If buffer is above the optimal/target level,
// bring active_worst_quality down depending on fullness of 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).
const VP9_COMMON *const cm = &cpi->common;
const RATE_CONTROL *rc = &cpi->rc;
// Buffer level below which we push active_worst to worst_quality.
int64_t critical_level = rc->optimal_buffer_level >> 3;
int64_t buff_lvl_step = 0;
int adjustment = 0;
int active_worst_quality;
int ambient_qp;
if (cm->frame_type == KEY_FRAME)
return rc->worst_quality;
// For ambient_qp we use minimum of avg_frame_qindex[KEY_FRAME/INTER_FRAME]
// for the first few frames following key frame. These are both initialized
// to worst_quality and updated with (3/4, 1/4) average in postencode_update.
// So for first few frames following key, the qp of that key frame is weighted
// into the active_worst_quality setting.
ambient_qp = (cm->current_video_frame < 5) ?
MIN(rc->avg_frame_qindex[INTER_FRAME], rc->avg_frame_qindex[KEY_FRAME]) :
rc->avg_frame_qindex[INTER_FRAME];
active_worst_quality = MIN(rc->worst_quality,
ambient_qp * 5 / 4);
if (rc->buffer_level > rc->optimal_buffer_level) {
// Adjust down.
// Maximum limit for down adjustment, ~30%.
int max_adjustment_down = active_worst_quality / 3;
if (max_adjustment_down) {
buff_lvl_step = ((rc->maximum_buffer_size -
rc->optimal_buffer_level) / max_adjustment_down);
if (buff_lvl_step)
adjustment = (int)((rc->buffer_level - rc->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 = (rc->optimal_buffer_level - critical_level);
if (buff_lvl_step) {
adjustment = (int)((rc->worst_quality - ambient_qp) *
(rc->optimal_buffer_level - rc->buffer_level) /
buff_lvl_step);
}
active_worst_quality = ambient_qp + adjustment;
}
} else {
// Set to worst_quality if buffer is below critical level.
active_worst_quality = rc->worst_quality;
}
return active_worst_quality;
}
static int rc_pick_q_and_bounds_one_pass_cbr(const VP9_COMP *cpi,
int *bottom_index,
int *top_index) {
const VP9_COMMON *const cm = &cpi->common;
const RATE_CONTROL *const rc = &cpi->rc;
int active_best_quality;
int active_worst_quality = calc_active_worst_quality_one_pass_cbr(cpi);
int q;
int *rtc_minq;
ASSIGN_MINQ_TABLE(cm->bit_depth, rtc_minq);
if (frame_is_intra_only(cm)) {
active_best_quality = rc->best_quality;
// Handle the special case for key frames forced when we have 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 = vp10_convert_qindex_to_q(qindex, cm->bit_depth);
int delta_qindex = vp10_compute_qdelta(rc, last_boosted_q,
(last_boosted_q * 0.75),
cm->bit_depth);
active_best_quality = MAX(qindex + delta_qindex, rc->best_quality);
} else if (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;
active_best_quality =
get_kf_active_quality(rc, rc->avg_frame_qindex[KEY_FRAME],
cm->bit_depth);
// Allow somewhat lower kf minq with small image formats.
if ((cm->width * cm->height) <= (352 * 288)) {
q_adj_factor -= 0.25;
}
// Convert the adjustment factor to a qindex delta
// on active_best_quality.
q_val = vp10_convert_qindex_to_q(active_best_quality, cm->bit_depth);
active_best_quality += vp10_compute_qdelta(rc, q_val,
q_val * q_adj_factor,
cm->bit_depth);
}
} else if (!rc->is_src_frame_alt_ref &&
!cpi->use_svc &&
(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;
}
active_best_quality = get_gf_active_quality(rc, q, cm->bit_depth);
} else {
// Use the lower of active_worst_quality and recent/average Q.
if (cm->current_video_frame > 1) {
if (rc->avg_frame_qindex[INTER_FRAME] < active_worst_quality)
active_best_quality = rtc_minq[rc->avg_frame_qindex[INTER_FRAME]];
else
active_best_quality = rtc_minq[active_worst_quality];
} else {
if (rc->avg_frame_qindex[KEY_FRAME] < active_worst_quality)
active_best_quality = rtc_minq[rc->avg_frame_qindex[KEY_FRAME]];
else
active_best_quality = rtc_minq[active_worst_quality];
}
}
// Clip the active best and worst quality values to limits
active_best_quality = clamp(active_best_quality,
rc->best_quality, rc->worst_quality);
active_worst_quality = clamp(active_worst_quality,
active_best_quality, rc->worst_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 &&
!(cm->current_video_frame == 0)) {
int qdelta = 0;
vpx_clear_system_state();
qdelta = vp10_compute_qdelta_by_rate(&cpi->rc, cm->frame_type,
active_worst_quality, 2.0,
cm->bit_depth);
*top_index = active_worst_quality + qdelta;
*top_index = (*top_index > *bottom_index) ? *top_index : *bottom_index;
}
#endif
// Special case code to try and match quality with forced key frames
if (cm->frame_type == KEY_FRAME && rc->this_key_frame_forced) {
q = rc->last_boosted_qindex;
} else {
q = vp10_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 (rc->this_frame_target >= rc->max_frame_bandwidth)
*top_index = q;
else
q = *top_index;
}
}
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;
}
static int get_active_cq_level(const RATE_CONTROL *rc,
const VP9EncoderConfig *const oxcf) {
static const double cq_adjust_threshold = 0.1;
int active_cq_level = oxcf->cq_level;
if (oxcf->rc_mode == VPX_CQ &&
rc->total_target_bits > 0) {
const double x = (double)rc->total_actual_bits / rc->total_target_bits;
if (x < cq_adjust_threshold) {
active_cq_level = (int)(active_cq_level * x / cq_adjust_threshold);
}
}
return active_cq_level;
}
static int rc_pick_q_and_bounds_one_pass_vbr(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 VP9EncoderConfig *const oxcf = &cpi->oxcf;
const int cq_level = get_active_cq_level(rc, oxcf);
int active_best_quality;
int active_worst_quality = calc_active_worst_quality_one_pass_vbr(cpi);
int q;
int *inter_minq;
ASSIGN_MINQ_TABLE(cm->bit_depth, inter_minq);
if (frame_is_intra_only(cm)) {
// Handle the special case for key frames forced when we have 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 = vp10_convert_qindex_to_q(qindex, cm->bit_depth);
int delta_qindex = vp10_compute_qdelta(rc, last_boosted_q,
last_boosted_q * 0.75,
cm->bit_depth);
active_best_quality = MAX(qindex + delta_qindex, rc->best_quality);
} else {
// not first frame of one pass and kf_boost is set
double q_adj_factor = 1.0;
double q_val;
active_best_quality =
get_kf_active_quality(rc, rc->avg_frame_qindex[KEY_FRAME],
cm->bit_depth);
// Allow somewhat lower kf minq with small image formats.
if ((cm->width * cm->height) <= (352 * 288)) {
q_adj_factor -= 0.25;
}
// Convert the adjustment factor to a qindex delta
// on active_best_quality.
q_val = vp10_convert_qindex_to_q(active_best_quality, cm->bit_depth);
active_best_quality += vp10_compute_qdelta(rc, q_val,
q_val * q_adj_factor,
cm->bit_depth);
}
} 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 = rc->avg_frame_qindex[KEY_FRAME];
}
// For constrained quality dont allow Q less than the cq level
if (oxcf->rc_mode == VPX_CQ) {
if (q < cq_level)
q = cq_level;
active_best_quality = get_gf_active_quality(rc, q, cm->bit_depth);
// Constrained quality use slightly lower active best.
active_best_quality = active_best_quality * 15 / 16;
} else if (oxcf->rc_mode == VPX_Q) {
if (!cpi->refresh_alt_ref_frame) {
active_best_quality = cq_level;
} else {
active_best_quality = get_gf_active_quality(rc, q, cm->bit_depth);
}
} else {
active_best_quality = get_gf_active_quality(rc, q, cm->bit_depth);
}
} else {
if (oxcf->rc_mode == VPX_Q) {
active_best_quality = cq_level;
} else {
// Use the lower of active_worst_quality and recent/average Q.
if (cm->current_video_frame > 1)
active_best_quality = inter_minq[rc->avg_frame_qindex[INTER_FRAME]];
else
active_best_quality = inter_minq[rc->avg_frame_qindex[KEY_FRAME]];
// For the constrained quality mode we don't want
// q to fall below the cq level.
if ((oxcf->rc_mode == VPX_CQ) &&
(active_best_quality < cq_level)) {
active_best_quality = cq_level;
}
}
}
// Clip the active best and worst quality values to limits
active_best_quality = clamp(active_best_quality,
rc->best_quality, rc->worst_quality);
active_worst_quality = clamp(active_worst_quality,
active_best_quality, rc->worst_quality);
*top_index = active_worst_quality;
*bottom_index = active_best_quality;
#if LIMIT_QRANGE_FOR_ALTREF_AND_KEY
{
int qdelta = 0;
vpx_clear_system_state();
// Limit Q range for the adaptive loop.
if (cm->frame_type == KEY_FRAME &&
!rc->this_key_frame_forced &&
!(cm->current_video_frame == 0)) {
qdelta = vp10_compute_qdelta_by_rate(&cpi->rc, cm->frame_type,
active_worst_quality, 2.0,
cm->bit_depth);
} else if (!rc->is_src_frame_alt_ref &&
(cpi->refresh_golden_frame || cpi->refresh_alt_ref_frame)) {
qdelta = vp10_compute_qdelta_by_rate(&cpi->rc, cm->frame_type,
active_worst_quality, 1.75,
cm->bit_depth);
}
*top_index = active_worst_quality + qdelta;
*top_index = (*top_index > *bottom_index) ? *top_index : *bottom_index;
}
#endif
if (oxcf->rc_mode == VPX_Q) {
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 = vp10_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 (rc->this_frame_target >= rc->max_frame_bandwidth)
*top_index = q;
else
q = *top_index;
}
}
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;
}
int vp10_frame_type_qdelta(const VP9_COMP *cpi, int rf_level, int q) {
static const double rate_factor_deltas[RATE_FACTOR_LEVELS] = {
1.00, // INTER_NORMAL
1.00, // INTER_HIGH
1.50, // GF_ARF_LOW
1.75, // GF_ARF_STD
2.00, // KF_STD
};
static const FRAME_TYPE frame_type[RATE_FACTOR_LEVELS] =
{INTER_FRAME, INTER_FRAME, INTER_FRAME, INTER_FRAME, KEY_FRAME};
const VP9_COMMON *const cm = &cpi->common;
int qdelta = vp10_compute_qdelta_by_rate(&cpi->rc, frame_type[rf_level],
q, rate_factor_deltas[rf_level],
cm->bit_depth);
return qdelta;
}
#define STATIC_MOTION_THRESH 95
static int rc_pick_q_and_bounds_two_pass(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 VP9EncoderConfig *const oxcf = &cpi->oxcf;
const GF_GROUP *gf_group = &cpi->twopass.gf_group;
const int cq_level = get_active_cq_level(rc, oxcf);
int active_best_quality;
int active_worst_quality = cpi->twopass.active_worst_quality;
int q;
int *inter_minq;
ASSIGN_MINQ_TABLE(cm->bit_depth, inter_minq);
if (frame_is_intra_only(cm) || vp10_is_upper_layer_key_frame(cpi)) {
// Handle the special case for key frames forced when we have 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) {
double last_boosted_q;
int delta_qindex;
int qindex;
if (cpi->twopass.last_kfgroup_zeromotion_pct >= STATIC_MOTION_THRESH) {
qindex = MIN(rc->last_kf_qindex, rc->last_boosted_qindex);
active_best_quality = qindex;
last_boosted_q = vp10_convert_qindex_to_q(qindex, cm->bit_depth);
delta_qindex = vp10_compute_qdelta(rc, last_boosted_q,
last_boosted_q * 1.25,
cm->bit_depth);
active_worst_quality = MIN(qindex + delta_qindex, active_worst_quality);
} else {
qindex = rc->last_boosted_qindex;
last_boosted_q = vp10_convert_qindex_to_q(qindex, cm->bit_depth);
delta_qindex = vp10_compute_qdelta(rc, last_boosted_q,
last_boosted_q * 0.75,
cm->bit_depth);
active_best_quality = MAX(qindex + delta_qindex, rc->best_quality);
}
} else {
// Not forced keyframe.
double q_adj_factor = 1.0;
double q_val;
// Baseline value derived from cpi->active_worst_quality and kf boost.
active_best_quality = get_kf_active_quality(rc, active_worst_quality,
cm->bit_depth);
// 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 = vp10_convert_qindex_to_q(active_best_quality, cm->bit_depth);
active_best_quality += vp10_compute_qdelta(rc, q_val,
q_val * q_adj_factor,
cm->bit_depth);
}
} 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->rc_mode == VPX_CQ) {
if (q < cq_level)
q = cq_level;
active_best_quality = get_gf_active_quality(rc, q, cm->bit_depth);
// Constrained quality use slightly lower active best.
active_best_quality = active_best_quality * 15 / 16;
} else if (oxcf->rc_mode == VPX_Q) {
if (!cpi->refresh_alt_ref_frame) {
active_best_quality = cq_level;
} else {
active_best_quality = get_gf_active_quality(rc, q, cm->bit_depth);
// Modify best quality for second level arfs. For mode VPX_Q this
// becomes the baseline frame q.
if (gf_group->rf_level[gf_group->index] == GF_ARF_LOW)
active_best_quality = (active_best_quality + cq_level + 1) / 2;
}
} else {
active_best_quality = get_gf_active_quality(rc, q, cm->bit_depth);
}
} else {
if (oxcf->rc_mode == VPX_Q) {
active_best_quality = cq_level;
} 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->rc_mode == VPX_CQ) &&
(active_best_quality < cq_level)) {
active_best_quality = cq_level;
}
}
}
// Extension to max or min Q if undershoot or overshoot is outside
// the permitted range.
if ((cpi->oxcf.rc_mode != VPX_Q) &&
(cpi->twopass.gf_zeromotion_pct < VLOW_MOTION_THRESHOLD)) {
if (frame_is_intra_only(cm) ||
(!rc->is_src_frame_alt_ref &&
(cpi->refresh_golden_frame || cpi->refresh_alt_ref_frame))) {
active_best_quality -=
(cpi->twopass.extend_minq + cpi->twopass.extend_minq_fast);
active_worst_quality += (cpi->twopass.extend_maxq / 2);
} else {
active_best_quality -=
(cpi->twopass.extend_minq + cpi->twopass.extend_minq_fast) / 2;
active_worst_quality += cpi->twopass.extend_maxq;
}
}
#if LIMIT_QRANGE_FOR_ALTREF_AND_KEY
vpx_clear_system_state();
// Static forced key frames Q restrictions dealt with elsewhere.
if (!((frame_is_intra_only(cm) || vp10_is_upper_layer_key_frame(cpi))) ||
!rc->this_key_frame_forced ||
(cpi->twopass.last_kfgroup_zeromotion_pct < STATIC_MOTION_THRESH)) {
int qdelta = vp10_frame_type_qdelta(cpi, gf_group->rf_level[gf_group->index],
active_worst_quality);
active_worst_quality = MAX(active_worst_quality + qdelta,
active_best_quality);
}
#endif
// Modify active_best_quality for downscaled normal frames.
if (rc->frame_size_selector != UNSCALED && !frame_is_kf_gf_arf(cpi)) {
int qdelta = vp10_compute_qdelta_by_rate(rc, cm->frame_type,
active_best_quality, 2.0,
cm->bit_depth);
active_best_quality = MAX(active_best_quality + qdelta, rc->best_quality);
}
active_best_quality = clamp(active_best_quality,
rc->best_quality, rc->worst_quality);
active_worst_quality = clamp(active_worst_quality,
active_best_quality, rc->worst_quality);
if (oxcf->rc_mode == VPX_Q) {
q = active_best_quality;
// Special case code to try and match quality with forced key frames.
} else if ((frame_is_intra_only(cm) || vp10_is_upper_layer_key_frame(cpi)) &&
rc->this_key_frame_forced) {
// If static since last kf use better of last boosted and last kf q.
if (cpi->twopass.last_kfgroup_zeromotion_pct >= STATIC_MOTION_THRESH) {
q = MIN(rc->last_kf_qindex, rc->last_boosted_qindex);
} else {
q = rc->last_boosted_qindex;
}
} else {
q = vp10_rc_regulate_q(cpi, rc->this_frame_target,
active_best_quality, active_worst_quality);
if (q > active_worst_quality) {
// Special case when we are targeting the max allowed rate.
if (rc->this_frame_target >= rc->max_frame_bandwidth)
active_worst_quality = q;
else
q = active_worst_quality;
}
}
clamp(q, active_best_quality, active_worst_quality);
*top_index = active_worst_quality;
*bottom_index = active_best_quality;
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;
}
int vp10_rc_pick_q_and_bounds(const VP9_COMP *cpi,
int *bottom_index, int *top_index) {
int q;
if (cpi->oxcf.pass == 0) {
if (cpi->oxcf.rc_mode == VPX_CBR)
q = rc_pick_q_and_bounds_one_pass_cbr(cpi, bottom_index, top_index);
else
q = rc_pick_q_and_bounds_one_pass_vbr(cpi, bottom_index, top_index);
} else {
q = rc_pick_q_and_bounds_two_pass(cpi, bottom_index, top_index);
}
if (cpi->sf.use_nonrd_pick_mode) {
if (cpi->sf.force_frame_boost == 1)
q -= cpi->sf.max_delta_qindex;
if (q < *bottom_index)
*bottom_index = q;
else if (q > *top_index)
*top_index = q;
}
return q;
}
void vp10_rc_compute_frame_size_bounds(const VP9_COMP *cpi,
int frame_target,
int *frame_under_shoot_limit,
int *frame_over_shoot_limit) {
if (cpi->oxcf.rc_mode == VPX_Q) {
*frame_under_shoot_limit = 0;
*frame_over_shoot_limit = INT_MAX;
} else {
// For very small rate targets where the fractional adjustment
// may be tiny make sure there is at least a minimum range.
const int tolerance = (cpi->sf.recode_tolerance * frame_target) / 100;
*frame_under_shoot_limit = MAX(frame_target - tolerance - 200, 0);
*frame_over_shoot_limit = MIN(frame_target + tolerance + 200,
cpi->rc.max_frame_bandwidth);
}
}
void vp10_rc_set_frame_target(VP9_COMP *cpi, int target) {
const VP9_COMMON *const cm = &cpi->common;
RATE_CONTROL *const rc = &cpi->rc;
rc->this_frame_target = target;
// Modify frame size target when down-scaling.
if (cpi->oxcf.resize_mode == RESIZE_DYNAMIC &&
rc->frame_size_selector != UNSCALED)
rc->this_frame_target = (int)(rc->this_frame_target
* rate_thresh_mult[rc->frame_size_selector]);
// Target rate per SB64 (including partial SB64s.
rc->sb64_target_rate = ((int64_t)rc->this_frame_target * 64 * 64) /
(cm->width * cm->height);
}
static void update_alt_ref_frame_stats(VP9_COMP *cpi) {
// this frame refreshes means next frames don't unless specified by user
RATE_CONTROL *const rc = &cpi->rc;
rc->frames_since_golden = 0;
// Mark the alt ref as done (setting to 0 means no further alt refs pending).
rc->source_alt_ref_pending = 0;
// Set the alternate reference frame active flag
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 we are not using alt ref in the up and coming group clear the arf
// active flag.
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 vp10_rc_postencode_update(VP9_COMP *cpi, uint64_t bytes_used) {
const VP9_COMMON *const cm = &cpi->common;
const VP9EncoderConfig *const oxcf = &cpi->oxcf;
RATE_CONTROL *const rc = &cpi->rc;
const int qindex = cm->base_qindex;
if (cpi->oxcf.aq_mode == CYCLIC_REFRESH_AQ && cm->seg.enabled) {
vp10_cyclic_refresh_postencode(cpi);
}
// Update rate control heuristics
rc->projected_frame_size = (int)(bytes_used << 3);
// Post encode loop adjustment of Q prediction.
vp10_rc_update_rate_correction_factors(cpi);
// Keep a record of last Q and ambient average Q.
if (cm->frame_type == KEY_FRAME) {
rc->last_q[KEY_FRAME] = qindex;
rc->avg_frame_qindex[KEY_FRAME] =
ROUND_POWER_OF_TWO(3 * rc->avg_frame_qindex[KEY_FRAME] + qindex, 2);
} else {
if (rc->is_src_frame_alt_ref ||
!(cpi->refresh_golden_frame || cpi->refresh_alt_ref_frame) ||
(cpi->use_svc && oxcf->rc_mode == VPX_CBR)) {
rc->last_q[INTER_FRAME] = qindex;
rc->avg_frame_qindex[INTER_FRAME] =
ROUND_POWER_OF_TWO(3 * rc->avg_frame_qindex[INTER_FRAME] + qindex, 2);
rc->ni_frames++;
rc->tot_q += vp10_convert_qindex_to_q(qindex, cm->bit_depth);
rc->avg_q = rc->tot_q / rc->ni_frames;
// Calculate the average Q for normal inter frames (not key or GFU
// frames).
rc->ni_tot_qi += 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 ((qindex < rc->last_boosted_qindex) ||
(cm->frame_type == KEY_FRAME) ||
(!rc->constrained_gf_group &&
(cpi->refresh_alt_ref_frame ||
(cpi->refresh_golden_frame && !rc->is_src_frame_alt_ref)))) {
rc->last_boosted_qindex = qindex;
}
if (cm->frame_type == KEY_FRAME)
rc->last_kf_qindex = qindex;
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;
rc->total_target_bits += cm->show_frame ? rc->avg_frame_bandwidth : 0;
rc->total_target_vs_actual = rc->total_actual_bits - rc->total_target_bits;
if (is_altref_enabled(cpi) && 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--;
}
// Trigger the resizing of the next frame if it is scaled.
if (oxcf->pass != 0) {
cpi->resize_pending =
rc->next_frame_size_selector != rc->frame_size_selector;
rc->frame_size_selector = rc->next_frame_size_selector;
}
}
void vp10_rc_postencode_update_drop_frame(VP9_COMP *cpi) {
// Update buffer level with zero size, update frame counters, and return.
update_buffer_level(cpi, 0);
cpi->rc.frames_since_key++;
cpi->rc.frames_to_key--;
cpi->rc.rc_2_frame = 0;
cpi->rc.rc_1_frame = 0;
}
// Use this macro to turn on/off use of alt-refs in one-pass mode.
#define USE_ALTREF_FOR_ONE_PASS 1
static int calc_pframe_target_size_one_pass_vbr(const VP9_COMP *const cpi) {
static const int af_ratio = 10;
const RATE_CONTROL *const rc = &cpi->rc;
int target;
#if USE_ALTREF_FOR_ONE_PASS
target = (!rc->is_src_frame_alt_ref &&
(cpi->refresh_golden_frame || cpi->refresh_alt_ref_frame)) ?
(rc->avg_frame_bandwidth * rc->baseline_gf_interval * af_ratio) /
(rc->baseline_gf_interval + af_ratio - 1) :
(rc->avg_frame_bandwidth * rc->baseline_gf_interval) /
(rc->baseline_gf_interval + af_ratio - 1);
#else
target = rc->avg_frame_bandwidth;
#endif
return vp10_rc_clamp_pframe_target_size(cpi, target);
}
static int calc_iframe_target_size_one_pass_vbr(const VP9_COMP *const cpi) {
static const int kf_ratio = 25;
const RATE_CONTROL *rc = &cpi->rc;
const int target = rc->avg_frame_bandwidth * kf_ratio;
return vp10_rc_clamp_iframe_target_size(cpi, target);
}
void vp10_rc_get_one_pass_vbr_params(VP9_COMP *cpi) {
VP9_COMMON *const cm = &cpi->common;
RATE_CONTROL *const rc = &cpi->rc;
int target;
// TODO(yaowu): replace the "auto_key && 0" below with proper decision logic.
if (!cpi->refresh_alt_ref_frame &&
(cm->current_video_frame == 0 ||
(cpi->frame_flags & FRAMEFLAGS_KEY) ||
rc->frames_to_key == 0 ||
(cpi->oxcf.auto_key && 0))) {
cm->frame_type = KEY_FRAME;
rc->this_key_frame_forced = cm->current_video_frame != 0 &&
rc->frames_to_key == 0;
rc->frames_to_key = cpi->oxcf.key_freq;
rc->kf_boost = DEFAULT_KF_BOOST;
rc->source_alt_ref_active = 0;
} else {
cm->frame_type = INTER_FRAME;
}
if (rc->frames_till_gf_update_due == 0) {
rc->baseline_gf_interval = (rc->min_gf_interval + rc->max_gf_interval) / 2;
rc->frames_till_gf_update_due = rc->baseline_gf_interval;
// NOTE: frames_till_gf_update_due must be <= frames_to_key.
if (rc->frames_till_gf_update_due > rc->frames_to_key) {
rc->frames_till_gf_update_due = rc->frames_to_key;
rc->constrained_gf_group = 1;
} else {
rc->constrained_gf_group = 0;
}
cpi->refresh_golden_frame = 1;
rc->source_alt_ref_pending = USE_ALTREF_FOR_ONE_PASS;
rc->gfu_boost = DEFAULT_GF_BOOST;
}
if (cm->frame_type == KEY_FRAME)
target = calc_iframe_target_size_one_pass_vbr(cpi);
else
target = calc_pframe_target_size_one_pass_vbr(cpi);
vp10_rc_set_frame_target(cpi, target);
}
static int calc_pframe_target_size_one_pass_cbr(const VP9_COMP *cpi) {
const VP9EncoderConfig *oxcf = &cpi->oxcf;
const RATE_CONTROL *rc = &cpi->rc;
const SVC *const svc = &cpi->svc;
const int64_t diff = rc->optimal_buffer_level - rc->buffer_level;
const int64_t one_pct_bits = 1 + rc->optimal_buffer_level / 100;
int min_frame_target = MAX(rc->avg_frame_bandwidth >> 4, FRAME_OVERHEAD_BITS);
int target;
if (oxcf->gf_cbr_boost_pct) {
const int af_ratio_pct = oxcf->gf_cbr_boost_pct + 100;
target = cpi->refresh_golden_frame ?
(rc->avg_frame_bandwidth * rc->baseline_gf_interval * af_ratio_pct) /
(rc->baseline_gf_interval * 100 + af_ratio_pct - 100) :
(rc->avg_frame_bandwidth * rc->baseline_gf_interval * 100) /
(rc->baseline_gf_interval * 100 + af_ratio_pct - 100);
} else {
target = rc->avg_frame_bandwidth;
}
if (is_one_pass_cbr_svc(cpi)) {
// Note that for layers, avg_frame_bandwidth is the cumulative
// per-frame-bandwidth. For the target size of this frame, use the
// layer average frame size (i.e., non-cumulative per-frame-bw).
int layer =
LAYER_IDS_TO_IDX(svc->spatial_layer_id,
svc->temporal_layer_id, svc->number_temporal_layers);
const LAYER_CONTEXT *lc = &svc->layer_context[layer];
target = lc->avg_frame_size;
min_frame_target = MAX(lc->avg_frame_size >> 4, FRAME_OVERHEAD_BITS);
}
if (diff > 0) {
// Lower the target bandwidth for this frame.
const int pct_low = (int)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 = (int)MIN(-diff / one_pct_bits, oxcf->over_shoot_pct);
target += (target * pct_high) / 200;
}
if (oxcf->rc_max_inter_bitrate_pct) {
const int max_rate = rc->avg_frame_bandwidth *
oxcf->rc_max_inter_bitrate_pct / 100;
target = MIN(target, max_rate);
}
return MAX(min_frame_target, target);
}
static int calc_iframe_target_size_one_pass_cbr(const VP9_COMP *cpi) {
const RATE_CONTROL *rc = &cpi->rc;
const VP9EncoderConfig *oxcf = &cpi->oxcf;
const SVC *const svc = &cpi->svc;
int target;
if (cpi->common.current_video_frame == 0) {
target = ((rc->starting_buffer_level / 2) > INT_MAX)
? INT_MAX : (int)(rc->starting_buffer_level / 2);
} else {
int kf_boost = 32;
double framerate = cpi->framerate;
if (svc->number_temporal_layers > 1 &&
oxcf->rc_mode == VPX_CBR) {
// Use the layer framerate for temporal layers CBR mode.
const int layer = LAYER_IDS_TO_IDX(svc->spatial_layer_id,
svc->temporal_layer_id, svc->number_temporal_layers);
const LAYER_CONTEXT *lc = &svc->layer_context[layer];
framerate = lc->framerate;
}
kf_boost = MAX(kf_boost, (int)(2 * framerate - 16));
if (rc->frames_since_key < framerate / 2) {
kf_boost = (int)(kf_boost * rc->frames_since_key /
(framerate / 2));
}
target = ((16 + kf_boost) * rc->avg_frame_bandwidth) >> 4;
}
return vp10_rc_clamp_iframe_target_size(cpi, target);
}
// Reset information needed to set proper reference frames and buffer updates
// for temporal layering. This is called when a key frame is encoded.
static void reset_temporal_layer_to_zero(VP9_COMP *cpi) {
int sl;
LAYER_CONTEXT *lc = NULL;
cpi->svc.temporal_layer_id = 0;
for (sl = 0; sl < cpi->svc.number_spatial_layers; ++sl) {
lc = &cpi->svc.layer_context[sl * cpi->svc.number_temporal_layers];
lc->current_video_frame_in_layer = 0;
lc->frames_from_key_frame = 0;
}
}
void vp10_rc_get_svc_params(VP9_COMP *cpi) {
VP9_COMMON *const cm = &cpi->common;
RATE_CONTROL *const rc = &cpi->rc;
int target = rc->avg_frame_bandwidth;
const int layer = LAYER_IDS_TO_IDX(cpi->svc.spatial_layer_id,
cpi->svc.temporal_layer_id, cpi->svc.number_temporal_layers);
if ((cm->current_video_frame == 0) ||
(cpi->frame_flags & FRAMEFLAGS_KEY) ||
(cpi->oxcf.auto_key && (rc->frames_since_key %
cpi->oxcf.key_freq == 0))) {
cm->frame_type = KEY_FRAME;
rc->source_alt_ref_active = 0;
if (is_two_pass_svc(cpi)) {
cpi->svc.layer_context[layer].is_key_frame = 1;
cpi->ref_frame_flags &=
(~VP9_LAST_FLAG & ~VP9_GOLD_FLAG & ~VP9_ALT_FLAG);
} else if (is_one_pass_cbr_svc(cpi)) {
cpi->svc.layer_context[layer].is_key_frame = 1;
reset_temporal_layer_to_zero(cpi);
cpi->ref_frame_flags &=
(~VP9_LAST_FLAG & ~VP9_GOLD_FLAG & ~VP9_ALT_FLAG);
// Assumption here is that LAST_FRAME is being updated for a keyframe.
// Thus no change in update flags.
target = calc_iframe_target_size_one_pass_cbr(cpi);
}
} else {
cm->frame_type = INTER_FRAME;
if (is_two_pass_svc(cpi)) {
LAYER_CONTEXT *lc = &cpi->svc.layer_context[layer];
if (cpi->svc.spatial_layer_id == 0) {
lc->is_key_frame = 0;
} else {
lc->is_key_frame =
cpi->svc.layer_context[cpi->svc.temporal_layer_id].is_key_frame;
if (lc->is_key_frame)
cpi->ref_frame_flags &= (~VP9_LAST_FLAG);
}
cpi->ref_frame_flags &= (~VP9_ALT_FLAG);
} else if (is_one_pass_cbr_svc(cpi)) {
LAYER_CONTEXT *lc = &cpi->svc.layer_context[layer];
if (cpi->svc.spatial_layer_id == 0) {
lc->is_key_frame = 0;
} else {
lc->is_key_frame =
cpi->svc.layer_context[cpi->svc.temporal_layer_id].is_key_frame;
}
target = calc_pframe_target_size_one_pass_cbr(cpi);
}
}
// Any update/change of global cyclic refresh parameters (amount/delta-qp)
// should be done here, before the frame qp is selected.
if (cpi->oxcf.aq_mode == CYCLIC_REFRESH_AQ)
vp10_cyclic_refresh_update_parameters(cpi);
vp10_rc_set_frame_target(cpi, target);
rc->frames_till_gf_update_due = INT_MAX;
rc->baseline_gf_interval = INT_MAX;
}
void vp10_rc_get_one_pass_cbr_params(VP9_COMP *cpi) {
VP9_COMMON *const cm = &cpi->common;
RATE_CONTROL *const rc = &cpi->rc;
int target;
// TODO(yaowu): replace the "auto_key && 0" below with proper decision logic.
if ((cm->current_video_frame == 0 ||
(cpi->frame_flags & FRAMEFLAGS_KEY) ||
rc->frames_to_key == 0 ||
(cpi->oxcf.auto_key && 0))) {
cm->frame_type = KEY_FRAME;
rc->this_key_frame_forced = cm->current_video_frame != 0 &&
rc->frames_to_key == 0;
rc->frames_to_key = cpi->oxcf.key_freq;
rc->kf_boost = DEFAULT_KF_BOOST;
rc->source_alt_ref_active = 0;
} else {
cm->frame_type = INTER_FRAME;
}
if (rc->frames_till_gf_update_due == 0) {
if (cpi->oxcf.aq_mode == CYCLIC_REFRESH_AQ)
vp10_cyclic_refresh_set_golden_update(cpi);
else
rc->baseline_gf_interval =
(rc->min_gf_interval + rc->max_gf_interval) / 2;
rc->frames_till_gf_update_due = rc->baseline_gf_interval;
// NOTE: frames_till_gf_update_due must be <= frames_to_key.
if (rc->frames_till_gf_update_due > rc->frames_to_key)
rc->frames_till_gf_update_due = rc->frames_to_key;
cpi->refresh_golden_frame = 1;
rc->gfu_boost = DEFAULT_GF_BOOST;
}
// Any update/change of global cyclic refresh parameters (amount/delta-qp)
// should be done here, before the frame qp is selected.
if (cpi->oxcf.aq_mode == CYCLIC_REFRESH_AQ)
vp10_cyclic_refresh_update_parameters(cpi);
if (cm->frame_type == KEY_FRAME)
target = calc_iframe_target_size_one_pass_cbr(cpi);
else
target = calc_pframe_target_size_one_pass_cbr(cpi);
vp10_rc_set_frame_target(cpi, target);
if (cpi->oxcf.resize_mode == RESIZE_DYNAMIC)
cpi->resize_pending = vp10_resize_one_pass_cbr(cpi);
else
cpi->resize_pending = 0;
}
int vp10_compute_qdelta(const RATE_CONTROL *rc, double qstart, double qtarget,
vpx_bit_depth_t bit_depth) {
int start_index = rc->worst_quality;
int target_index = rc->worst_quality;
int i;
// Convert the average q value to an index.
for (i = rc->best_quality; i < rc->worst_quality; ++i) {
start_index = i;
if (vp10_convert_qindex_to_q(i, bit_depth) >= qstart)
break;
}
// Convert the q target to an index
for (i = rc->best_quality; i < rc->worst_quality; ++i) {
target_index = i;
if (vp10_convert_qindex_to_q(i, bit_depth) >= qtarget)
break;
}
return target_index - start_index;
}
int vp10_compute_qdelta_by_rate(const RATE_CONTROL *rc, FRAME_TYPE frame_type,
int qindex, double rate_target_ratio,
vpx_bit_depth_t bit_depth) {
int target_index = rc->worst_quality;
int i;
// Look up the current projected bits per block for the base index
const int base_bits_per_mb = vp10_rc_bits_per_mb(frame_type, qindex, 1.0,
bit_depth);
// Find the target bits per mb based on the base value and given ratio.
const int target_bits_per_mb = (int)(rate_target_ratio * base_bits_per_mb);
// Convert the q target to an index
for (i = rc->best_quality; i < rc->worst_quality; ++i) {
if (vp10_rc_bits_per_mb(frame_type, i, 1.0, bit_depth) <=
target_bits_per_mb) {
target_index = i;
break;
}
}
return target_index - qindex;
}
void vp10_rc_set_gf_interval_range(const VP9_COMP *const cpi,
RATE_CONTROL *const rc) {
const VP9EncoderConfig *const oxcf = &cpi->oxcf;
// Set Maximum gf/arf interval
rc->max_gf_interval = oxcf->max_gf_interval;
rc->min_gf_interval = oxcf->min_gf_interval;
if (rc->min_gf_interval == 0)
rc->min_gf_interval = vp10_rc_get_default_min_gf_interval(
oxcf->width, oxcf->height, cpi->framerate);
if (rc->max_gf_interval == 0)
rc->max_gf_interval = vp10_rc_get_default_max_gf_interval(
cpi->framerate, rc->min_gf_interval);
// Extended interval for genuinely static scenes
rc->static_scene_max_gf_interval = MAX_LAG_BUFFERS * 2;
if (is_altref_enabled(cpi)) {
if (rc->static_scene_max_gf_interval > oxcf->lag_in_frames - 1)
rc->static_scene_max_gf_interval = oxcf->lag_in_frames - 1;
}
if (rc->max_gf_interval > rc->static_scene_max_gf_interval)
rc->max_gf_interval = rc->static_scene_max_gf_interval;
// Clamp min to max
rc->min_gf_interval = MIN(rc->min_gf_interval, rc->max_gf_interval);
}
void vp10_rc_update_framerate(VP9_COMP *cpi) {
const VP9_COMMON *const cm = &cpi->common;
const VP9EncoderConfig *const oxcf = &cpi->oxcf;
RATE_CONTROL *const rc = &cpi->rc;
int vbr_max_bits;
rc->avg_frame_bandwidth = (int)(oxcf->target_bandwidth / cpi->framerate);
rc->min_frame_bandwidth = (int)(rc->avg_frame_bandwidth *
oxcf->two_pass_vbrmin_section / 100);
rc->min_frame_bandwidth = MAX(rc->min_frame_bandwidth, FRAME_OVERHEAD_BITS);
// A maximum bitrate for a frame is defined.
// The baseline for this aligns with HW implementations that
// can support decode of 1080P content up to a bitrate of MAX_MB_RATE bits
// per 16x16 MB (averaged over a frame). However this limit is extended if
// a very high rate is given on the command line or the the rate cannnot
// be acheived because of a user specificed max q (e.g. when the user
// specifies lossless encode.
vbr_max_bits = (int)(((int64_t)rc->avg_frame_bandwidth *
oxcf->two_pass_vbrmax_section) / 100);
rc->max_frame_bandwidth = MAX(MAX((cm->MBs * MAX_MB_RATE), MAXRATE_1080P),
vbr_max_bits);
vp10_rc_set_gf_interval_range(cpi, rc);
}
#define VBR_PCT_ADJUSTMENT_LIMIT 50
// For VBR...adjustment to the frame target based on error from previous frames
static void vbr_rate_correction(VP9_COMP *cpi, int *this_frame_target) {
RATE_CONTROL *const rc = &cpi->rc;
int64_t vbr_bits_off_target = rc->vbr_bits_off_target;
int max_delta;
double position_factor = 1.0;
// How far through the clip are we.
// This number is used to damp the per frame rate correction.
// Range 0 - 1.0
if (cpi->twopass.total_stats.count) {
position_factor = sqrt((double)cpi->common.current_video_frame /
cpi->twopass.total_stats.count);
}
max_delta = (int)(position_factor *
((*this_frame_target * VBR_PCT_ADJUSTMENT_LIMIT) / 100));
// vbr_bits_off_target > 0 means we have extra bits to spend
if (vbr_bits_off_target > 0) {
*this_frame_target +=
(vbr_bits_off_target > max_delta) ? max_delta
: (int)vbr_bits_off_target;
} else {
*this_frame_target -=
(vbr_bits_off_target < -max_delta) ? max_delta
: (int)-vbr_bits_off_target;
}
// Fast redistribution of bits arising from massive local undershoot.
// Dont do it for kf,arf,gf or overlay frames.
if (!frame_is_kf_gf_arf(cpi) && !rc->is_src_frame_alt_ref &&
rc->vbr_bits_off_target_fast) {
int one_frame_bits = MAX(rc->avg_frame_bandwidth, *this_frame_target);
int fast_extra_bits;
fast_extra_bits =
(int)MIN(rc->vbr_bits_off_target_fast, one_frame_bits);
fast_extra_bits = (int)MIN(fast_extra_bits,
MAX(one_frame_bits / 8, rc->vbr_bits_off_target_fast / 8));
*this_frame_target += (int)fast_extra_bits;
rc->vbr_bits_off_target_fast -= fast_extra_bits;
}
}
void vp10_set_target_rate(VP9_COMP *cpi) {
RATE_CONTROL *const rc = &cpi->rc;
int target_rate = rc->base_frame_target;
// Correction to rate target based on prior over or under shoot.
if (cpi->oxcf.rc_mode == VPX_VBR || cpi->oxcf.rc_mode == VPX_CQ)
vbr_rate_correction(cpi, &target_rate);
vp10_rc_set_frame_target(cpi, target_rate);
}
// Check if we should resize, based on average QP from past x frames.
// Only allow for resize at most one scale down for now, scaling factor is 2.
int vp10_resize_one_pass_cbr(VP9_COMP *cpi) {
const VP9_COMMON *const cm = &cpi->common;
RATE_CONTROL *const rc = &cpi->rc;
int resize_now = 0;
cpi->resize_scale_num = 1;
cpi->resize_scale_den = 1;
// Don't resize on key frame; reset the counters on key frame.
if (cm->frame_type == KEY_FRAME) {
cpi->resize_avg_qp = 0;
cpi->resize_count = 0;
return 0;
}
// Resize based on average buffer underflow and QP over some window.
// Ignore samples close to key frame, since QP is usually high after key.
if (cpi->rc.frames_since_key > 2 * cpi->framerate) {
const int window = (int)(5 * cpi->framerate);
cpi->resize_avg_qp += cm->base_qindex;
if (cpi->rc.buffer_level < (int)(30 * rc->optimal_buffer_level / 100))
++cpi->resize_buffer_underflow;
++cpi->resize_count;
// Check for resize action every "window" frames.
if (cpi->resize_count >= window) {
int avg_qp = cpi->resize_avg_qp / cpi->resize_count;
// Resize down if buffer level has underflowed sufficent amount in past
// window, and we are at original resolution.
// Resize back up if average QP is low, and we are currently in a resized
// down state.
if (cpi->resize_state == 0 &&
cpi->resize_buffer_underflow > (cpi->resize_count >> 2)) {
resize_now = 1;
cpi->resize_state = 1;
} else if (cpi->resize_state == 1 &&
avg_qp < 40 * cpi->rc.worst_quality / 100) {
resize_now = -1;
cpi->resize_state = 0;
}
// Reset for next window measurement.
cpi->resize_avg_qp = 0;
cpi->resize_count = 0;
cpi->resize_buffer_underflow = 0;
}
}
// If decision is to resize, reset some quantities, and check is we should
// reduce rate correction factor,
if (resize_now != 0) {
int target_bits_per_frame;
int active_worst_quality;
int qindex;
int tot_scale_change;
// For now, resize is by 1/2 x 1/2.
cpi->resize_scale_num = 1;
cpi->resize_scale_den = 2;
tot_scale_change = (cpi->resize_scale_den * cpi->resize_scale_den) /
(cpi->resize_scale_num * cpi->resize_scale_num);
// Reset buffer level to optimal, update target size.
rc->buffer_level = rc->optimal_buffer_level;
rc->bits_off_target = rc->optimal_buffer_level;
rc->this_frame_target = calc_pframe_target_size_one_pass_cbr(cpi);
// Reset cyclic refresh parameters.
if (cpi->oxcf.aq_mode == CYCLIC_REFRESH_AQ && cm->seg.enabled)
vp10_cyclic_refresh_reset_resize(cpi);
// Get the projected qindex, based on the scaled target frame size (scaled
// so target_bits_per_mb in vp10_rc_regulate_q will be correct target).
target_bits_per_frame = (resize_now == 1) ?
rc->this_frame_target * tot_scale_change :
rc->this_frame_target / tot_scale_change;
active_worst_quality = calc_active_worst_quality_one_pass_cbr(cpi);
qindex = vp10_rc_regulate_q(cpi,
target_bits_per_frame,
rc->best_quality,
active_worst_quality);
// If resize is down, check if projected q index is close to worst_quality,
// and if so, reduce the rate correction factor (since likely can afford
// lower q for resized frame).
if (resize_now == 1 &&
qindex > 90 * cpi->rc.worst_quality / 100) {
rc->rate_correction_factors[INTER_NORMAL] *= 0.85;
}
// If resize is back up, check if projected q index is too much above the
// current base_qindex, and if so, reduce the rate correction factor
// (since prefer to keep q for resized frame at least close to previous q).
if (resize_now == -1 &&
qindex > 130 * cm->base_qindex / 100) {
rc->rate_correction_factors[INTER_NORMAL] *= 0.9;
}
}
return resize_now;
}