ref: 74ddde01c07967276e67d5e3ca1bef506dfc30f7
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 <assert.h> #include <limits.h> #include <math.h> #include <stdio.h> #include <stdlib.h> #include <string.h> #include "vpx_mem/vpx_mem.h" #include "vp9/common/vp9_alloccommon.h" #include "vp9/common/vp9_common.h" #include "vp9/common/vp9_entropymode.h" #include "vp9/common/vp9_quant_common.h" #include "vp9/common/vp9_seg_common.h" #include "vp9/common/vp9_systemdependent.h" #include "vp9/encoder/vp9_encodemv.h" #include "vp9/encoder/vp9_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 // 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 arfgf_low_motion_minq[QINDEX_RANGE]; static int arfgf_high_motion_minq[QINDEX_RANGE]; static int inter_minq[QINDEX_RANGE]; static int rtc_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 get_minq_index(double maxq, double x3, double x2, double x1) { 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 <= vp9_convert_qindex_to_q(i)) return i; return QINDEX_RANGE - 1; } void vp9_rc_init_minq_luts() { int i; for (i = 0; i < QINDEX_RANGE; i++) { const double maxq = vp9_convert_qindex_to_q(i); kf_low_motion_minq[i] = get_minq_index(maxq, 0.000001, -0.0004, 0.125); kf_high_motion_minq[i] = get_minq_index(maxq, 0.000002, -0.0012, 0.50); arfgf_low_motion_minq[i] = get_minq_index(maxq, 0.0000015, -0.0009, 0.30); arfgf_high_motion_minq[i] = get_minq_index(maxq, 0.0000021, -0.00125, 0.50); inter_minq[i] = get_minq_index(maxq, 0.00000271, -0.00113, 0.90); rtc_minq[i] = get_minq_index(maxq, 0.00000271, -0.00113, 0.70); } } // 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)(enumerator * correction_factor / q); } static int estimate_bits_at_q(FRAME_TYPE frame_type, int q, int mbs, double correction_factor) { const int bpm = (int)(vp9_rc_bits_per_mb(frame_type, q, correction_factor)); return ((uint64_t)bpm * mbs) >> BPER_MB_NORMBITS; } int vp9_rc_clamp_pframe_target_size(const VP9_COMP *const cpi, int target) { const RATE_CONTROL *rc = &cpi->rc; 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; return target; } int vp9_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 layers, given the encoded current layer. static void update_layer_buffer_level(SVC *svc, int encoded_frame_size) { int temporal_layer = 0; int current_temporal_layer = svc->temporal_layer_id; for (temporal_layer = current_temporal_layer + 1; temporal_layer < svc->number_temporal_layers; ++temporal_layer) { LAYER_CONTEXT *lc = &svc->layer_context[temporal_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 (cpi->use_svc && cpi->oxcf.rc_mode == VPX_CBR) { update_layer_buffer_level(&cpi->svc, encoded_frame_size); } } void vp9_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->best_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->baseline_gf_interval = DEFAULT_GF_INTERVAL; 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 = vp9_convert_qindex_to_q(oxcf->worst_allowed_q); for (i = 0; i < RATE_FACTOR_LEVELS; ++i) { rc->rate_correction_factors[i] = 1.0; } } int vp9_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; if (cpi->common.frame_type == KEY_FRAME) { return 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]; return 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)) return rc->rate_correction_factors[GF_ARF_STD]; else return rc->rate_correction_factors[INTER_NORMAL]; } } static void set_rate_correction_factor(VP9_COMP *cpi, double factor) { RATE_CONTROL *const rc = &cpi->rc; 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)) rc->rate_correction_factors[GF_ARF_STD] = factor; else rc->rate_correction_factors[INTER_NORMAL] = factor; } } void vp9_rc_update_rate_correction_factors(VP9_COMP *cpi, int damp_var) { 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 vp9_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 projected_size_based_on_q = estimate_bits_at_q(cm->frame_type, cm->base_qindex, cm->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. target_bits_per_mb = ((uint64_t)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; } } static int get_kf_active_quality(const RATE_CONTROL *const rc, int q) { 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) { 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 >> 2; int64_t buff_lvl_step = 0; int adjustment = 0; int active_worst_quality; if (cm->frame_type == KEY_FRAME) return rc->worst_quality; if (cm->current_video_frame > 1) active_worst_quality = MIN(rc->worst_quality, rc->avg_frame_qindex[INTER_FRAME] * 5 / 4); else active_worst_quality = MIN(rc->worst_quality, rc->avg_frame_qindex[KEY_FRAME] * 3 / 2); 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 - rc->avg_frame_qindex[INTER_FRAME]) * (rc->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; } 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; if (frame_is_intra_only(cm)) { active_best_quality = rc->best_quality; // 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(rc, last_boosted_q, (last_boosted_q * 0.75)); 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]); // 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 = vp9_convert_qindex_to_q(active_best_quality); active_best_quality += vp9_compute_qdelta(rc, q_val, q_val * q_adj_factor); } } 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); } 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; vp9_clear_system_state(); qdelta = vp9_compute_qdelta_by_rate(&cpi->rc, cm->frame_type, active_worst_quality, 2.0); *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 = 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 (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 = 0.5; 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; 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 = vp9_convert_qindex_to_q(qindex); int delta_qindex = vp9_compute_qdelta(rc, last_boosted_q, last_boosted_q * 0.75); 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]); // 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 = vp9_convert_qindex_to_q(active_best_quality); active_best_quality += vp9_compute_qdelta(rc, q_val, q_val * q_adj_factor); } } 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); // 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); } } else { active_best_quality = get_gf_active_quality(rc, q); } } 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; vp9_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 = vp9_compute_qdelta_by_rate(&cpi->rc, cm->frame_type, active_worst_quality, 2.0); } else if (!rc->is_src_frame_alt_ref && (cpi->refresh_golden_frame || cpi->refresh_alt_ref_frame)) { qdelta = vp9_compute_qdelta_by_rate(&cpi->rc, cm->frame_type, active_worst_quality, 1.75); } *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 = 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 (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 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 int cq_level = get_active_cq_level(rc, oxcf); int active_best_quality; int active_worst_quality = cpi->twopass.active_worst_quality; int q; if (frame_is_intra_only(cm) || vp9_is_upper_layer_key_frame(cpi)) { // 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(rc, last_boosted_q, last_boosted_q * 0.75); 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); // 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(rc, q_val, q_val * q_adj_factor); } } 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); // 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); } } else { active_best_quality = get_gf_active_quality(rc, q); } } 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; } } } // 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 vp9_clear_system_state(); { const GF_GROUP *const gf_group = &cpi->twopass.gf_group; 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 }; const double rate_factor = rate_factor_deltas[gf_group->rf_level[gf_group->index]]; int qdelta = vp9_compute_qdelta_by_rate(&cpi->rc, cm->frame_type, active_worst_quality, rate_factor); *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 = 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 (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 vp9_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 vp9_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 vp9_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; // 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 (cpi->oxcf.pass == 2) { if (!rc->source_alt_ref_pending && cpi->twopass.gf_group.rf_level[0] == GF_ARF_STD) rc->source_alt_ref_active = 0; } else 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) { 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; // Update rate control heuristics rc->projected_frame_size = (int)(bytes_used << 3); // Post encode loop adjustment of Q prediction. vp9_rc_update_rate_correction_factors( cpi, (cpi->sf.recode_loop >= ALLOW_RECODE_KFARFGF || oxcf->rc_mode == VPX_CBR) ? 2 : 0); // 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 += vp9_convert_qindex_to_q(qindex); 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) || ((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 = 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--; } } void vp9_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->common.last_frame_type = cpi->common.frame_type; cpi->rc.frames_since_key++; cpi->rc.frames_to_key--; } // 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 vp9_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 vp9_rc_clamp_iframe_target_size(cpi, target); } void vp9_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 = DEFAULT_GF_INTERVAL; 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->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); vp9_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 = rc->avg_frame_bandwidth; if (svc->number_temporal_layers > 1 && oxcf->rc_mode == VPX_CBR) { // 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 current_temporal_layer = svc->temporal_layer_id; const LAYER_CONTEXT *lc = &svc->layer_context[current_temporal_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; } 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 LAYER_CONTEXT *lc = &svc->layer_context[svc->temporal_layer_id]; 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 vp9_rc_clamp_iframe_target_size(cpi, target); } void vp9_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; 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[cpi->svc.spatial_layer_id].is_key_frame = 1; cpi->ref_frame_flags &= (~VP9_LAST_FLAG & ~VP9_GOLD_FLAG & ~VP9_ALT_FLAG); } if (cpi->oxcf.pass == 0 && cpi->oxcf.rc_mode == VPX_CBR) { 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[cpi->svc.spatial_layer_id]; if (cpi->svc.spatial_layer_id == 0) { lc->is_key_frame = 0; } else { lc->is_key_frame = cpi->svc.layer_context[0].is_key_frame; if (lc->is_key_frame) cpi->ref_frame_flags &= (~VP9_LAST_FLAG); } cpi->ref_frame_flags &= (~VP9_ALT_FLAG); } if (cpi->oxcf.pass == 0 && cpi->oxcf.rc_mode == VPX_CBR) { target = calc_pframe_target_size_one_pass_cbr(cpi); } } vp9_rc_set_frame_target(cpi, target); rc->frames_till_gf_update_due = INT_MAX; rc->baseline_gf_interval = INT_MAX; } void vp9_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; target = calc_iframe_target_size_one_pass_cbr(cpi); } else { cm->frame_type = INTER_FRAME; target = calc_pframe_target_size_one_pass_cbr(cpi); } vp9_rc_set_frame_target(cpi, target); // Don't use gf_update by default in CBR mode. rc->frames_till_gf_update_due = INT_MAX; rc->baseline_gf_interval = INT_MAX; } int vp9_compute_qdelta(const RATE_CONTROL *rc, double qstart, double qtarget) { 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 (vp9_convert_qindex_to_q(i) >= qstart) break; } // Convert the q target to an index for (i = rc->best_quality; i < rc->worst_quality; ++i) { target_index = i; if (vp9_convert_qindex_to_q(i) >= qtarget) break; } return target_index - start_index; } int vp9_compute_qdelta_by_rate(const RATE_CONTROL *rc, FRAME_TYPE frame_type, int qindex, double rate_target_ratio) { 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 = vp9_rc_bits_per_mb(frame_type, qindex, 1.0); // 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) { target_index = i; if (vp9_rc_bits_per_mb(frame_type, i, 1.0) <= target_bits_per_mb ) break; } return target_index - qindex; } void vp9_rc_set_gf_max_interval(const VP9_COMP *const cpi, RATE_CONTROL *const rc) { const VP9EncoderConfig *const oxcf = &cpi->oxcf; // Set Maximum gf/arf interval rc->max_gf_interval = 16; // Extended interval for genuinely static scenes rc->static_scene_max_gf_interval = oxcf->key_freq >> 1; if (rc->static_scene_max_gf_interval > (MAX_LAG_BUFFERS * 2)) 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; } void vp9_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); vp9_rc_set_gf_max_interval(cpi, rc); }