| /* |
| * Copyright (c) 2010 The WebM project authors. All Rights Reserved. |
| * |
| * Use of this source code is governed by a BSD-style license |
| * that can be found in the LICENSE file in the root of the source |
| * tree. An additional intellectual property rights grant can be found |
| * in the file PATENTS. All contributing project authors may |
| * be found in the AUTHORS file in the root of the source tree. |
| */ |
| |
| |
| #include <stdlib.h> |
| #include <stdio.h> |
| #include <string.h> |
| #include <limits.h> |
| #include <assert.h> |
| |
| #include "math.h" |
| #include "vp8/common/common.h" |
| #include "ratectrl.h" |
| #include "vp8/common/entropymode.h" |
| #include "vpx_mem/vpx_mem.h" |
| #include "vp8/common/systemdependent.h" |
| #include "encodemv.h" |
| |
| |
| #define MIN_BPB_FACTOR 0.005 |
| #define MAX_BPB_FACTOR 50 |
| |
| extern const MB_PREDICTION_MODE vp8_mode_order[MAX_MODES]; |
| extern const MV_REFERENCE_FRAME vp8_ref_frame_order[MAX_MODES]; |
| |
| |
| |
| #ifdef MODE_STATS |
| extern int y_modes[VP8_YMODES]; |
| extern int uv_modes[VP8_UV_MODES]; |
| extern int b_modes[B_MODE_COUNT]; |
| |
| extern int inter_y_modes[MB_MODE_COUNT]; |
| extern int inter_uv_modes[VP8_UV_MODES]; |
| extern int inter_b_modes[B_MODE_COUNT]; |
| #endif |
| |
| // Bits Per MB at different Q (Multiplied by 512) |
| #define BPER_MB_NORMBITS 9 |
| |
| // % adjustment to target kf size based on seperation from previous frame |
| static const int kf_boost_seperation_adjustment[16] = |
| { |
| 30, 40, 50, 55, 60, 65, 70, 75, |
| 80, 85, 90, 95, 100, 100, 100, 100, |
| }; |
| |
| static const int gf_adjust_table[101] = |
| { |
| 100, |
| 115, 130, 145, 160, 175, 190, 200, 210, 220, 230, |
| 240, 260, 270, 280, 290, 300, 310, 320, 330, 340, |
| 350, 360, 370, 380, 390, 400, 400, 400, 400, 400, |
| 400, 400, 400, 400, 400, 400, 400, 400, 400, 400, |
| 400, 400, 400, 400, 400, 400, 400, 400, 400, 400, |
| 400, 400, 400, 400, 400, 400, 400, 400, 400, 400, |
| 400, 400, 400, 400, 400, 400, 400, 400, 400, 400, |
| 400, 400, 400, 400, 400, 400, 400, 400, 400, 400, |
| 400, 400, 400, 400, 400, 400, 400, 400, 400, 400, |
| 400, 400, 400, 400, 400, 400, 400, 400, 400, 400, |
| }; |
| |
| static const int gf_intra_usage_adjustment[20] = |
| { |
| 125, 120, 115, 110, 105, 100, 95, 85, 80, 75, |
| 70, 65, 60, 55, 50, 50, 50, 50, 50, 50, |
| }; |
| |
| static const int gf_interval_table[101] = |
| { |
| 7, |
| 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, |
| 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, |
| 7, 7, 7, 7, 7, 7, 7, 7, 7, 7, |
| 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, |
| 8, 8, 8, 8, 8, 8, 8, 8, 8, 8, |
| 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, |
| 9, 9, 9, 9, 9, 9, 9, 9, 9, 9, |
| 10, 10, 10, 10, 10, 10, 10, 10, 10, 10, |
| 10, 10, 10, 10, 10, 10, 10, 10, 10, 10, |
| 11, 11, 11, 11, 11, 11, 11, 11, 11, 11, |
| }; |
| |
| static const unsigned int prior_key_frame_weight[KEY_FRAME_CONTEXT] = { 1, 2, 3, 4, 5 }; |
| |
| // 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 vp8_convert_qindex_to_q( int qindex ) |
| { |
| // Convert the index to a real Q value (scaled down to match old Q values) |
| return (double)vp8_ac_yquant( qindex, 0 ) / 4.0; |
| } |
| |
| int vp8_gfboost_qadjust( int qindex ) |
| { |
| int retval; |
| double q; |
| |
| q = vp8_convert_qindex_to_q(qindex); |
| retval = (int)( ( 0.00000828 * q * q * q ) + |
| ( -0.0055 * q * q ) + |
| ( 1.32 * q ) + 79.3 ); |
| return retval; |
| } |
| |
| int kfboost_qadjust( int qindex ) |
| { |
| int retval; |
| double q; |
| |
| q = vp8_convert_qindex_to_q(qindex); |
| retval = (int)( ( 0.00000973 * q * q * q ) + |
| ( -0.00613 * q * q ) + |
| ( 1.316 * q ) + 121.2 ); |
| return retval; |
| } |
| |
| int vp8_bits_per_mb( FRAME_TYPE frame_type, int qindex ) |
| { |
| if ( frame_type == KEY_FRAME ) |
| return (int)(4500000 / vp8_convert_qindex_to_q(qindex)); |
| else |
| return (int)(2850000 / vp8_convert_qindex_to_q(qindex)); |
| } |
| |
| |
| void vp8_save_coding_context(VP8_COMP *cpi) |
| { |
| CODING_CONTEXT *const cc = & cpi->coding_context; |
| |
| // Stores a snapshot of key state variables which can subsequently be |
| // restored with a call to vp8_restore_coding_context. These functions are |
| // intended for use in a re-code loop in vp8_compress_frame where the |
| // quantizer value is adjusted between loop iterations. |
| |
| cc->frames_since_key = cpi->frames_since_key; |
| cc->filter_level = cpi->common.filter_level; |
| cc->frames_till_gf_update_due = cpi->frames_till_gf_update_due; |
| cc->frames_since_golden = cpi->common.frames_since_golden; |
| |
| vp8_copy(cc->mvc, cpi->common.fc.mvc); |
| vp8_copy(cc->mvcosts, cpi->mb.mvcosts); |
| |
| vp8_copy(cc->kf_ymode_prob, cpi->common.kf_ymode_prob); |
| vp8_copy(cc->ymode_prob, cpi->common.fc.ymode_prob); |
| vp8_copy(cc->kf_uv_mode_prob, cpi->common.kf_uv_mode_prob); |
| vp8_copy(cc->uv_mode_prob, cpi->common.fc.uv_mode_prob); |
| |
| vp8_copy(cc->ymode_count, cpi->ymode_count); |
| vp8_copy(cc->uv_mode_count, cpi->uv_mode_count); |
| |
| |
| // Stats |
| #ifdef MODE_STATS |
| vp8_copy(cc->y_modes, y_modes); |
| vp8_copy(cc->uv_modes, uv_modes); |
| vp8_copy(cc->b_modes, b_modes); |
| vp8_copy(cc->inter_y_modes, inter_y_modes); |
| vp8_copy(cc->inter_uv_modes, inter_uv_modes); |
| vp8_copy(cc->inter_b_modes, inter_b_modes); |
| #endif |
| |
| cc->this_frame_percent_intra = cpi->this_frame_percent_intra; |
| } |
| |
| |
| void vp8_restore_coding_context(VP8_COMP *cpi) |
| { |
| CODING_CONTEXT *const cc = & cpi->coding_context; |
| |
| // Restore key state variables to the snapshot state stored in the |
| // previous call to vp8_save_coding_context. |
| |
| cpi->frames_since_key = cc->frames_since_key; |
| cpi->common.filter_level = cc->filter_level; |
| cpi->frames_till_gf_update_due = cc->frames_till_gf_update_due; |
| cpi->common.frames_since_golden = cc->frames_since_golden; |
| |
| vp8_copy(cpi->common.fc.mvc, cc->mvc); |
| |
| vp8_copy(cpi->mb.mvcosts, cc->mvcosts); |
| vp8_copy(cpi->common.kf_ymode_prob, cc->kf_ymode_prob); |
| vp8_copy(cpi->common.fc.ymode_prob, cc->ymode_prob); |
| vp8_copy(cpi->common.kf_uv_mode_prob, cc->kf_uv_mode_prob); |
| vp8_copy(cpi->common.fc.uv_mode_prob, cc->uv_mode_prob); |
| |
| vp8_copy(cpi->ymode_count, cc->ymode_count); |
| vp8_copy(cpi->uv_mode_count, cc->uv_mode_count); |
| |
| // Stats |
| #ifdef MODE_STATS |
| vp8_copy(y_modes, cc->y_modes); |
| vp8_copy(uv_modes, cc->uv_modes); |
| vp8_copy(b_modes, cc->b_modes); |
| vp8_copy(inter_y_modes, cc->inter_y_modes); |
| vp8_copy(inter_uv_modes, cc->inter_uv_modes); |
| vp8_copy(inter_b_modes, cc->inter_b_modes); |
| #endif |
| |
| |
| cpi->this_frame_percent_intra = cc->this_frame_percent_intra; |
| } |
| |
| |
| void vp8_setup_key_frame(VP8_COMP *cpi) |
| { |
| // Setup for Key frame: |
| |
| vp8_default_coef_probs(& cpi->common); |
| vp8_kf_default_bmode_probs(cpi->common.kf_bmode_prob); |
| |
| vpx_memcpy(cpi->common.fc.mvc, vp8_default_mv_context, sizeof(vp8_default_mv_context)); |
| { |
| int flag[2] = {1, 1}; |
| vp8_build_component_cost_table(cpi->mb.mvcost, (const MV_CONTEXT *) cpi->common.fc.mvc, flag); |
| } |
| |
| vpx_memset(cpi->common.fc.pre_mvc, 0, sizeof(cpi->common.fc.pre_mvc)); //initialize pre_mvc to all zero. |
| |
| //cpi->common.filter_level = 0; // Reset every key frame. |
| cpi->common.filter_level = cpi->common.base_qindex * 3 / 8 ; |
| |
| // Provisional interval before next GF |
| if (cpi->auto_gold) |
| //cpi->frames_till_gf_update_due = DEFAULT_GF_INTERVAL; |
| cpi->frames_till_gf_update_due = cpi->baseline_gf_interval; |
| else |
| cpi->frames_till_gf_update_due = cpi->goldfreq; |
| |
| cpi->common.refresh_golden_frame = TRUE; |
| cpi->common.refresh_alt_ref_frame = TRUE; |
| |
| vpx_memcpy(&cpi->common.lfc, &cpi->common.fc, sizeof(cpi->common.fc)); |
| vpx_memcpy(&cpi->common.lfc_a, &cpi->common.fc, sizeof(cpi->common.fc)); |
| |
| vp8_init_mode_contexts(&cpi->common); |
| vpx_memcpy( cpi->common.vp8_mode_contexts, |
| cpi->common.mode_context, |
| sizeof(cpi->common.mode_context)); |
| vpx_memcpy( cpi->common.vp8_mode_contexts, |
| default_vp8_mode_contexts, |
| sizeof(default_vp8_mode_contexts)); |
| } |
| void vp8_setup_inter_frame(VP8_COMP *cpi) |
| { |
| if(cpi->common.refresh_alt_ref_frame) |
| { |
| vpx_memcpy( &cpi->common.fc, |
| &cpi->common.lfc_a, |
| sizeof(cpi->common.fc)); |
| vpx_memcpy( cpi->common.vp8_mode_contexts, |
| cpi->common.mode_context_a, |
| sizeof(cpi->common.vp8_mode_contexts)); |
| } |
| else |
| { |
| vpx_memcpy( &cpi->common.fc, |
| &cpi->common.lfc, |
| sizeof(cpi->common.fc)); |
| vpx_memcpy( cpi->common.vp8_mode_contexts, |
| cpi->common.mode_context, |
| sizeof(cpi->common.vp8_mode_contexts)); |
| } |
| } |
| |
| |
| static int estimate_bits_at_q(int frame_kind, int Q, int MBs, |
| double correction_factor) |
| { |
| int Bpm = (int)(.5 + correction_factor * vp8_bits_per_mb(frame_kind, Q)); |
| |
| /* Attempt to retain reasonable accuracy without overflow. The cutoff is |
| * chosen such that the maximum product of Bpm and MBs fits 31 bits. The |
| * largest Bpm takes 20 bits. |
| */ |
| if (MBs > (1 << 11)) |
| return (Bpm >> BPER_MB_NORMBITS) * MBs; |
| else |
| return (Bpm * MBs) >> BPER_MB_NORMBITS; |
| } |
| |
| |
| static void calc_iframe_target_size(VP8_COMP *cpi) |
| { |
| // boost defaults to half second |
| int kf_boost; |
| int target; |
| |
| // Clear down mmx registers to allow floating point in what follows |
| vp8_clear_system_state(); //__asm emms; |
| |
| if (cpi->oxcf.fixed_q >= 0) |
| { |
| int Q = cpi->oxcf.key_q; |
| |
| target = estimate_bits_at_q(INTRA_FRAME, Q, cpi->common.MBs, |
| cpi->key_frame_rate_correction_factor); |
| } |
| else if (cpi->pass == 2) |
| { |
| // New Two pass RC |
| target = cpi->per_frame_bandwidth; |
| } |
| // First Frame is a special case |
| else if (cpi->common.current_video_frame == 0) |
| { |
| /* 1 Pass there is no information on which to base size so use |
| * bandwidth per second * fraction of the initial buffer |
| * level |
| */ |
| target = cpi->oxcf.starting_buffer_level / 2; |
| |
| if(target > cpi->oxcf.target_bandwidth * 3 / 2) |
| target = cpi->oxcf.target_bandwidth * 3 / 2; |
| } |
| else |
| { |
| // if this keyframe was forced, use a more recent Q estimate |
| int Q = (cpi->common.frame_flags & FRAMEFLAGS_KEY) |
| ? cpi->avg_frame_qindex : cpi->ni_av_qi; |
| |
| // Boost depends somewhat on frame rate |
| kf_boost = (int)(2 * cpi->output_frame_rate - 16); |
| |
| // adjustment up based on q |
| kf_boost = kf_boost * kfboost_qadjust(Q) / 100; |
| |
| // frame separation adjustment ( down) |
| if (cpi->frames_since_key < cpi->output_frame_rate / 2) |
| kf_boost = (int)(kf_boost |
| * cpi->frames_since_key / (cpi->output_frame_rate / 2)); |
| |
| if (kf_boost < 16) |
| kf_boost = 16; |
| |
| target = ((16 + kf_boost) * cpi->per_frame_bandwidth) >> 4; |
| } |
| |
| |
| if (cpi->oxcf.rc_max_intra_bitrate_pct) |
| { |
| unsigned int max_rate = cpi->per_frame_bandwidth |
| * cpi->oxcf.rc_max_intra_bitrate_pct / 100; |
| |
| if (target > max_rate) |
| target = max_rate; |
| } |
| |
| cpi->this_frame_target = target; |
| |
| // TODO: if we separate rate targeting from Q targetting, move this. |
| // Reset the active worst quality to the baseline value for key frames. |
| if (cpi->pass != 2) |
| cpi->active_worst_quality = cpi->worst_quality; |
| |
| } |
| |
| |
| // Do the best we can to define the parameteres for the next GF based on what information we have available. |
| static void calc_gf_params(VP8_COMP *cpi) |
| { |
| int Q = (cpi->oxcf.fixed_q < 0) ? cpi->last_q[INTER_FRAME] : cpi->oxcf.fixed_q; |
| int Boost = 0; |
| |
| int gf_frame_useage = 0; // Golden frame useage since last GF |
| int tot_mbs = cpi->recent_ref_frame_usage[INTRA_FRAME] + |
| cpi->recent_ref_frame_usage[LAST_FRAME] + |
| cpi->recent_ref_frame_usage[GOLDEN_FRAME] + |
| cpi->recent_ref_frame_usage[ALTREF_FRAME]; |
| |
| int pct_gf_active = (100 * cpi->gf_active_count) / (cpi->common.mb_rows * cpi->common.mb_cols); |
| |
| // Reset the last boost indicator |
| //cpi->last_boost = 100; |
| |
| if (tot_mbs) |
| gf_frame_useage = (cpi->recent_ref_frame_usage[GOLDEN_FRAME] + cpi->recent_ref_frame_usage[ALTREF_FRAME]) * 100 / tot_mbs; |
| |
| if (pct_gf_active > gf_frame_useage) |
| gf_frame_useage = pct_gf_active; |
| |
| // Not two pass |
| if (cpi->pass != 2) |
| { |
| // Single Pass lagged mode: TBD |
| if (FALSE) |
| { |
| } |
| |
| // Single Pass compression: Has to use current and historical data |
| else |
| { |
| #if 0 |
| // Experimental code |
| int index = cpi->one_pass_frame_index; |
| int frames_to_scan = (cpi->max_gf_interval <= MAX_LAG_BUFFERS) ? cpi->max_gf_interval : MAX_LAG_BUFFERS; |
| |
| /* |
| // *************** Experimental code - incomplete |
| double decay_val = 1.0; |
| double IIAccumulator = 0.0; |
| double last_iiaccumulator = 0.0; |
| double IIRatio; |
| |
| cpi->one_pass_frame_index = cpi->common.current_video_frame%MAX_LAG_BUFFERS; |
| |
| for ( i = 0; i < (frames_to_scan - 1); i++ ) |
| { |
| if ( index < 0 ) |
| index = MAX_LAG_BUFFERS; |
| index --; |
| |
| if ( cpi->one_pass_frame_stats[index].frame_coded_error > 0.0 ) |
| { |
| IIRatio = cpi->one_pass_frame_stats[index].frame_intra_error / cpi->one_pass_frame_stats[index].frame_coded_error; |
| |
| if ( IIRatio > 30.0 ) |
| IIRatio = 30.0; |
| } |
| else |
| IIRatio = 30.0; |
| |
| IIAccumulator += IIRatio * decay_val; |
| |
| decay_val = decay_val * cpi->one_pass_frame_stats[index].frame_pcnt_inter; |
| |
| if ( (i > MIN_GF_INTERVAL) && |
| ((IIAccumulator - last_iiaccumulator) < 2.0) ) |
| { |
| break; |
| } |
| last_iiaccumulator = IIAccumulator; |
| } |
| |
| Boost = IIAccumulator*100.0/16.0; |
| cpi->baseline_gf_interval = i; |
| |
| */ |
| #else |
| |
| /*************************************************************/ |
| // OLD code |
| |
| // Adjust boost based upon ambient Q |
| Boost = vp8_gfboost_qadjust(Q); |
| |
| // Adjust based upon most recently measure intra useage |
| Boost = Boost * gf_intra_usage_adjustment[(cpi->this_frame_percent_intra < 15) ? cpi->this_frame_percent_intra : 14] / 100; |
| |
| // Adjust gf boost based upon GF usage since last GF |
| Boost = Boost * gf_adjust_table[gf_frame_useage] / 100; |
| #endif |
| } |
| |
| // golden frame boost without recode loop often goes awry. be safe by keeping numbers down. |
| if (!cpi->sf.recode_loop) |
| { |
| if (cpi->compressor_speed == 2) |
| Boost = Boost / 2; |
| } |
| |
| // Apply an upper limit based on Q for 1 pass encodes |
| // TODO. |
| // This is a temporay measure oas one pass not really supported yet in |
| // the experimental branch |
| if (Boost > 600 && (cpi->pass == 0)) |
| Boost = 600; |
| |
| // Apply lower limits to boost. |
| else if (Boost < 110) |
| Boost = 110; |
| |
| // Note the boost used |
| cpi->last_boost = Boost; |
| |
| } |
| |
| // Estimate next interval |
| // This is updated once the real frame size/boost is known. |
| if (cpi->oxcf.fixed_q == -1) |
| { |
| if (cpi->pass == 2) // 2 Pass |
| { |
| cpi->frames_till_gf_update_due = cpi->baseline_gf_interval; |
| } |
| else // 1 Pass |
| { |
| cpi->frames_till_gf_update_due = cpi->baseline_gf_interval; |
| |
| if (cpi->last_boost > 750) |
| cpi->frames_till_gf_update_due++; |
| |
| if (cpi->last_boost > 1000) |
| cpi->frames_till_gf_update_due++; |
| |
| if (cpi->last_boost > 1250) |
| cpi->frames_till_gf_update_due++; |
| |
| if (cpi->last_boost >= 1500) |
| cpi->frames_till_gf_update_due ++; |
| |
| if (gf_interval_table[gf_frame_useage] > cpi->frames_till_gf_update_due) |
| cpi->frames_till_gf_update_due = gf_interval_table[gf_frame_useage]; |
| |
| if (cpi->frames_till_gf_update_due > cpi->max_gf_interval) |
| cpi->frames_till_gf_update_due = cpi->max_gf_interval; |
| } |
| } |
| else |
| cpi->frames_till_gf_update_due = cpi->baseline_gf_interval; |
| |
| // ARF on or off |
| if (cpi->pass != 2) |
| { |
| // For now Alt ref is not allowed except in 2 pass modes. |
| cpi->source_alt_ref_pending = FALSE; |
| |
| /*if ( cpi->oxcf.fixed_q == -1) |
| { |
| if ( cpi->oxcf.play_alternate && (cpi->last_boost > (100 + (AF_THRESH*cpi->frames_till_gf_update_due)) ) ) |
| cpi->source_alt_ref_pending = TRUE; |
| else |
| cpi->source_alt_ref_pending = FALSE; |
| }*/ |
| } |
| } |
| |
| |
| static void calc_pframe_target_size(VP8_COMP *cpi) |
| { |
| int min_frame_target; |
| int Adjustment; |
| |
| min_frame_target = 0; |
| |
| if (cpi->pass == 2) |
| { |
| min_frame_target = cpi->min_frame_bandwidth; |
| |
| if (min_frame_target < (cpi->av_per_frame_bandwidth >> 5)) |
| min_frame_target = cpi->av_per_frame_bandwidth >> 5; |
| } |
| else if (min_frame_target < cpi->per_frame_bandwidth / 4) |
| min_frame_target = cpi->per_frame_bandwidth / 4; |
| |
| |
| // Special alt reference frame case |
| if (cpi->common.refresh_alt_ref_frame) |
| { |
| if (cpi->pass == 2) |
| { |
| cpi->per_frame_bandwidth = cpi->twopass.gf_bits; // Per frame bit target for the alt ref frame |
| cpi->this_frame_target = cpi->per_frame_bandwidth; |
| } |
| |
| /* One Pass ??? TBD */ |
| /*else |
| { |
| int frames_in_section; |
| int allocation_chunks; |
| int Q = (cpi->oxcf.fixed_q < 0) ? cpi->last_q[INTER_FRAME] : cpi->oxcf.fixed_q; |
| int alt_boost; |
| int max_arf_rate; |
| |
| alt_boost = (cpi->gfu_boost * 3 * vp8_gfboost_qadjust(Q)) / (2 * 100); |
| alt_boost += (cpi->frames_till_gf_update_due * 50); |
| |
| // If alt ref is not currently active then we have a pottential double hit with GF and ARF so reduce the boost a bit. |
| // A similar thing is done on GFs that preceed a arf update. |
| if ( !cpi->source_alt_ref_active ) |
| alt_boost = alt_boost * 3 / 4; |
| |
| frames_in_section = cpi->frames_till_gf_update_due+1; // Standard frames + GF |
| allocation_chunks = (frames_in_section * 100) + alt_boost; |
| |
| // Normalize Altboost and allocations chunck down to prevent overflow |
| while ( alt_boost > 1000 ) |
| { |
| alt_boost /= 2; |
| allocation_chunks /= 2; |
| } |
| |
| else |
| { |
| int bits_in_section; |
| |
| if ( cpi->kf_overspend_bits > 0 ) |
| { |
| Adjustment = (cpi->kf_bitrate_adjustment <= cpi->kf_overspend_bits) ? cpi->kf_bitrate_adjustment : cpi->kf_overspend_bits; |
| |
| if ( Adjustment > (cpi->per_frame_bandwidth - min_frame_target) ) |
| Adjustment = (cpi->per_frame_bandwidth - min_frame_target); |
| |
| cpi->kf_overspend_bits -= Adjustment; |
| |
| // Calculate an inter frame bandwidth target for the next few frames designed to recover |
| // any extra bits spent on the key frame. |
| cpi->inter_frame_target = cpi->per_frame_bandwidth - Adjustment; |
| if ( cpi->inter_frame_target < min_frame_target ) |
| cpi->inter_frame_target = min_frame_target; |
| } |
| else |
| cpi->inter_frame_target = cpi->per_frame_bandwidth; |
| |
| bits_in_section = cpi->inter_frame_target * frames_in_section; |
| |
| // Avoid loss of precision but avoid overflow |
| if ( (bits_in_section>>7) > allocation_chunks ) |
| cpi->this_frame_target = alt_boost * (bits_in_section / allocation_chunks); |
| else |
| cpi->this_frame_target = (alt_boost * bits_in_section) / allocation_chunks; |
| } |
| } |
| */ |
| } |
| |
| // Normal frames (gf,and inter) |
| else |
| { |
| // 2 pass |
| if (cpi->pass == 2) |
| { |
| cpi->this_frame_target = cpi->per_frame_bandwidth; |
| } |
| // 1 pass |
| else |
| { |
| // Make rate adjustment to recover bits spent in key frame |
| // Test to see if the key frame inter data rate correction should still be in force |
| if (cpi->kf_overspend_bits > 0) |
| { |
| Adjustment = (cpi->kf_bitrate_adjustment <= cpi->kf_overspend_bits) ? cpi->kf_bitrate_adjustment : cpi->kf_overspend_bits; |
| |
| if (Adjustment > (cpi->per_frame_bandwidth - min_frame_target)) |
| Adjustment = (cpi->per_frame_bandwidth - min_frame_target); |
| |
| cpi->kf_overspend_bits -= Adjustment; |
| |
| // Calculate an inter frame bandwidth target for the next few frames designed to recover |
| // any extra bits spent on the key frame. |
| cpi->this_frame_target = cpi->per_frame_bandwidth - Adjustment; |
| |
| if (cpi->this_frame_target < min_frame_target) |
| cpi->this_frame_target = min_frame_target; |
| } |
| else |
| cpi->this_frame_target = cpi->per_frame_bandwidth; |
| |
| // If appropriate make an adjustment to recover bits spent on a recent GF |
| if ((cpi->gf_overspend_bits > 0) && (cpi->this_frame_target > min_frame_target)) |
| { |
| int Adjustment = (cpi->non_gf_bitrate_adjustment <= cpi->gf_overspend_bits) ? cpi->non_gf_bitrate_adjustment : cpi->gf_overspend_bits; |
| |
| if (Adjustment > (cpi->this_frame_target - min_frame_target)) |
| Adjustment = (cpi->this_frame_target - min_frame_target); |
| |
| cpi->gf_overspend_bits -= Adjustment; |
| cpi->this_frame_target -= Adjustment; |
| } |
| |
| // Apply small + and - boosts for non gf frames |
| if ((cpi->last_boost > 150) && (cpi->frames_till_gf_update_due > 0) && |
| (cpi->current_gf_interval >= (MIN_GF_INTERVAL << 1))) |
| { |
| // % Adjustment limited to the range 1% to 10% |
| Adjustment = (cpi->last_boost - 100) >> 5; |
| |
| if (Adjustment < 1) |
| Adjustment = 1; |
| else if (Adjustment > 10) |
| Adjustment = 10; |
| |
| // Convert to bits |
| Adjustment = (cpi->this_frame_target * Adjustment) / 100; |
| |
| if (Adjustment > (cpi->this_frame_target - min_frame_target)) |
| Adjustment = (cpi->this_frame_target - min_frame_target); |
| |
| if (cpi->common.frames_since_golden == (cpi->current_gf_interval >> 1)) |
| cpi->this_frame_target += ((cpi->current_gf_interval - 1) * Adjustment); |
| else |
| cpi->this_frame_target -= Adjustment; |
| } |
| } |
| } |
| |
| // Sanity check that the total sum of adjustments is not above the maximum allowed |
| // That is that having allowed for KF and GF penalties we have not pushed the |
| // current interframe target to low. If the adjustment we apply here is not capable of recovering |
| // all the extra bits we have spent in the KF or GF then the remainder will have to be recovered over |
| // a longer time span via other buffer / rate control mechanisms. |
| if (cpi->this_frame_target < min_frame_target) |
| cpi->this_frame_target = min_frame_target; |
| |
| if (!cpi->common.refresh_alt_ref_frame) |
| // Note the baseline target data rate for this inter frame. |
| cpi->inter_frame_target = cpi->this_frame_target; |
| |
| // One Pass specific code |
| if (cpi->pass == 0) |
| { |
| // Adapt target frame size with respect to any buffering constraints: |
| if (cpi->buffered_mode) |
| { |
| int one_percent_bits = 1 + cpi->oxcf.optimal_buffer_level / 100; |
| |
| if ((cpi->buffer_level < cpi->oxcf.optimal_buffer_level) || |
| (cpi->bits_off_target < cpi->oxcf.optimal_buffer_level)) |
| { |
| int percent_low = 0; |
| |
| // Decide whether or not we need to adjust the frame data rate target. |
| // |
| // If we are are below the optimal buffer fullness level and adherence |
| // to buffering contraints is important to the end useage then adjust |
| // the per frame target. |
| if ((cpi->oxcf.end_usage == USAGE_STREAM_FROM_SERVER) && |
| (cpi->buffer_level < cpi->oxcf.optimal_buffer_level)) |
| { |
| percent_low = |
| (cpi->oxcf.optimal_buffer_level - cpi->buffer_level) / |
| one_percent_bits; |
| } |
| // Are we overshooting the long term clip data rate... |
| else if (cpi->bits_off_target < 0) |
| { |
| // Adjust per frame data target downwards to compensate. |
| percent_low = (int)(100 * -cpi->bits_off_target / |
| (cpi->total_byte_count * 8)); |
| } |
| |
| if (percent_low > cpi->oxcf.under_shoot_pct) |
| percent_low = cpi->oxcf.under_shoot_pct; |
| else if (percent_low < 0) |
| percent_low = 0; |
| |
| // lower the target bandwidth for this frame. |
| cpi->this_frame_target -= (cpi->this_frame_target * percent_low) |
| / 200; |
| |
| // Are we using allowing control of active_worst_allowed_q |
| // according to buffer level. |
| if (cpi->auto_worst_q) |
| { |
| int critical_buffer_level; |
| |
| // For streaming applications the most important factor is |
| // cpi->buffer_level as this takes into account the |
| // specified short term buffering constraints. However, |
| // hitting the long term clip data rate target is also |
| // important. |
| if (cpi->oxcf.end_usage == USAGE_STREAM_FROM_SERVER) |
| { |
| // Take the smaller of cpi->buffer_level and |
| // cpi->bits_off_target |
| critical_buffer_level = |
| (cpi->buffer_level < cpi->bits_off_target) |
| ? cpi->buffer_level : cpi->bits_off_target; |
| } |
| // For local file playback short term buffering contraints |
| // are less of an issue |
| else |
| { |
| // Consider only how we are doing for the clip as a |
| // whole |
| critical_buffer_level = cpi->bits_off_target; |
| } |
| |
| // Set the active worst quality based upon the selected |
| // buffer fullness number. |
| if (critical_buffer_level < cpi->oxcf.optimal_buffer_level) |
| { |
| if ( critical_buffer_level > |
| (cpi->oxcf.optimal_buffer_level >> 2) ) |
| { |
| int64_t qadjustment_range = |
| cpi->worst_quality - cpi->ni_av_qi; |
| int64_t above_base = |
| (critical_buffer_level - |
| (cpi->oxcf.optimal_buffer_level >> 2)); |
| |
| // Step active worst quality down from |
| // cpi->ni_av_qi when (critical_buffer_level == |
| // cpi->optimal_buffer_level) to |
| // cpi->worst_quality when |
| // (critical_buffer_level == |
| // cpi->optimal_buffer_level >> 2) |
| cpi->active_worst_quality = |
| cpi->worst_quality - |
| ((qadjustment_range * above_base) / |
| (cpi->oxcf.optimal_buffer_level*3>>2)); |
| } |
| else |
| { |
| cpi->active_worst_quality = cpi->worst_quality; |
| } |
| } |
| else |
| { |
| cpi->active_worst_quality = cpi->ni_av_qi; |
| } |
| } |
| else |
| { |
| cpi->active_worst_quality = cpi->worst_quality; |
| } |
| } |
| else |
| { |
| int percent_high = 0; |
| |
| if ((cpi->oxcf.end_usage == USAGE_STREAM_FROM_SERVER) |
| && (cpi->buffer_level > cpi->oxcf.optimal_buffer_level)) |
| { |
| percent_high = (cpi->buffer_level |
| - cpi->oxcf.optimal_buffer_level) |
| / one_percent_bits; |
| } |
| else if (cpi->bits_off_target > cpi->oxcf.optimal_buffer_level) |
| { |
| percent_high = (int)((100 * cpi->bits_off_target) |
| / (cpi->total_byte_count * 8)); |
| } |
| |
| if (percent_high > cpi->oxcf.over_shoot_pct) |
| percent_high = cpi->oxcf.over_shoot_pct; |
| else if (percent_high < 0) |
| percent_high = 0; |
| |
| cpi->this_frame_target += (cpi->this_frame_target * |
| percent_high) / 200; |
| |
| |
| // Are we allowing control of active_worst_allowed_q according to bufferl level. |
| if (cpi->auto_worst_q) |
| { |
| // When using the relaxed buffer model stick to the user specified value |
| cpi->active_worst_quality = cpi->ni_av_qi; |
| } |
| else |
| { |
| cpi->active_worst_quality = cpi->worst_quality; |
| } |
| } |
| |
| // Set active_best_quality to prevent quality rising too high |
| cpi->active_best_quality = cpi->best_quality; |
| |
| // Worst quality obviously must not be better than best quality |
| if (cpi->active_worst_quality <= cpi->active_best_quality) |
| cpi->active_worst_quality = cpi->active_best_quality + 1; |
| |
| } |
| // Unbuffered mode (eg. video conferencing) |
| else |
| { |
| // Set the active worst quality |
| cpi->active_worst_quality = cpi->worst_quality; |
| } |
| |
| // Special trap for constrained quality mode |
| // "active_worst_quality" may never drop below cq level |
| // for any frame type. |
| if ( cpi->oxcf.end_usage == USAGE_CONSTRAINED_QUALITY && |
| cpi->active_worst_quality < cpi->cq_target_quality) |
| { |
| cpi->active_worst_quality = cpi->cq_target_quality; |
| } |
| } |
| |
| // Test to see if we have to drop a frame |
| // The auto-drop frame code is only used in buffered mode. |
| // In unbufferd mode (eg vide conferencing) the descision to |
| // code or drop a frame is made outside the codec in response to real |
| // world comms or buffer considerations. |
| if (cpi->drop_frames_allowed && cpi->buffered_mode && |
| (cpi->oxcf.end_usage == USAGE_STREAM_FROM_SERVER) && |
| ((cpi->common.frame_type != KEY_FRAME))) //|| !cpi->oxcf.allow_spatial_resampling) ) |
| { |
| // Check for a buffer underun-crisis in which case we have to drop a frame |
| if ((cpi->buffer_level < 0)) |
| { |
| #if 0 |
| FILE *f = fopen("dec.stt", "a"); |
| fprintf(f, "%10d %10d %10d %10d ***** BUFFER EMPTY\n", |
| (int) cpi->common.current_video_frame, |
| cpi->decimation_factor, cpi->common.horiz_scale, |
| (cpi->buffer_level * 100) / cpi->oxcf.optimal_buffer_level); |
| fclose(f); |
| #endif |
| //vpx_log("Decoder: Drop frame due to bandwidth: %d \n",cpi->buffer_level, cpi->av_per_frame_bandwidth); |
| |
| cpi->drop_frame = TRUE; |
| } |
| |
| #if 0 |
| // Check for other drop frame crtieria (Note 2 pass cbr uses decimation on whole KF sections) |
| else if ((cpi->buffer_level < cpi->oxcf.drop_frames_water_mark * cpi->oxcf.optimal_buffer_level / 100) && |
| (cpi->drop_count < cpi->max_drop_count) && (cpi->pass == 0)) |
| { |
| cpi->drop_frame = TRUE; |
| } |
| |
| #endif |
| |
| if (cpi->drop_frame) |
| { |
| // Update the buffer level variable. |
| cpi->bits_off_target += cpi->av_per_frame_bandwidth; |
| |
| // Clip the buffer level at the maximum buffer size |
| if (cpi->bits_off_target > cpi->oxcf.maximum_buffer_size) |
| cpi->bits_off_target = cpi->oxcf.maximum_buffer_size; |
| |
| cpi->buffer_level = cpi->bits_off_target; |
| } |
| else |
| cpi->drop_count = 0; |
| } |
| |
| // Adjust target frame size for Golden Frames: |
| if (cpi->oxcf.error_resilient_mode == 0 && |
| (cpi->frames_till_gf_update_due == 0) && !cpi->drop_frame) |
| { |
| //int Boost = 0; |
| int Q = (cpi->oxcf.fixed_q < 0) ? cpi->last_q[INTER_FRAME] : cpi->oxcf.fixed_q; |
| |
| int gf_frame_useage = 0; // Golden frame useage since last GF |
| int tot_mbs = cpi->recent_ref_frame_usage[INTRA_FRAME] + |
| cpi->recent_ref_frame_usage[LAST_FRAME] + |
| cpi->recent_ref_frame_usage[GOLDEN_FRAME] + |
| cpi->recent_ref_frame_usage[ALTREF_FRAME]; |
| |
| int pct_gf_active = (100 * cpi->gf_active_count) / (cpi->common.mb_rows * cpi->common.mb_cols); |
| |
| // Reset the last boost indicator |
| //cpi->last_boost = 100; |
| |
| if (tot_mbs) |
| gf_frame_useage = (cpi->recent_ref_frame_usage[GOLDEN_FRAME] + cpi->recent_ref_frame_usage[ALTREF_FRAME]) * 100 / tot_mbs; |
| |
| if (pct_gf_active > gf_frame_useage) |
| gf_frame_useage = pct_gf_active; |
| |
| // Is a fixed manual GF frequency being used |
| if (cpi->auto_gold) |
| { |
| // For one pass throw a GF if recent frame intra useage is low or the GF useage is high |
| if ((cpi->pass == 0) && (cpi->this_frame_percent_intra < 15 || gf_frame_useage >= 5)) |
| cpi->common.refresh_golden_frame = TRUE; |
| |
| // Two pass GF descision |
| else if (cpi->pass == 2) |
| cpi->common.refresh_golden_frame = TRUE; |
| } |
| |
| #if 0 |
| |
| // Debug stats |
| if (0) |
| { |
| FILE *f; |
| |
| f = fopen("gf_useaget.stt", "a"); |
| fprintf(f, " %8ld %10ld %10ld %10ld %10ld\n", |
| cpi->common.current_video_frame, cpi->gfu_boost, vp8_gfboost_qadjust(Q), cpi->gfu_boost, gf_frame_useage); |
| fclose(f); |
| } |
| |
| #endif |
| |
| if (cpi->common.refresh_golden_frame == TRUE) |
| { |
| #if 0 |
| |
| if (0) // p_gw |
| { |
| FILE *f; |
| |
| f = fopen("GFexit.stt", "a"); |
| fprintf(f, "%8ld GF coded\n", cpi->common.current_video_frame); |
| fclose(f); |
| } |
| |
| #endif |
| |
| if (cpi->auto_adjust_gold_quantizer) |
| { |
| calc_gf_params(cpi); |
| } |
| |
| // If we are using alternate ref instead of gf then do not apply the boost |
| // It will instead be applied to the altref update |
| // Jims modified boost |
| if (!cpi->source_alt_ref_active) |
| { |
| if (cpi->oxcf.fixed_q < 0) |
| { |
| if (cpi->pass == 2) |
| { |
| cpi->this_frame_target = cpi->per_frame_bandwidth; // The spend on the GF is defined in the two pass code for two pass encodes |
| } |
| else |
| { |
| int Boost = cpi->last_boost; |
| int frames_in_section = cpi->frames_till_gf_update_due + 1; |
| int allocation_chunks = (frames_in_section * 100) + (Boost - 100); |
| int bits_in_section = cpi->inter_frame_target * frames_in_section; |
| |
| // Normalize Altboost and allocations chunck down to prevent overflow |
| while (Boost > 1000) |
| { |
| Boost /= 2; |
| allocation_chunks /= 2; |
| } |
| |
| // Avoid loss of precision but avoid overflow |
| if ((bits_in_section >> 7) > allocation_chunks) |
| cpi->this_frame_target = Boost * (bits_in_section / allocation_chunks); |
| else |
| cpi->this_frame_target = (Boost * bits_in_section) / allocation_chunks; |
| } |
| } |
| else |
| cpi->this_frame_target = |
| (estimate_bits_at_q(1, Q, cpi->common.MBs, 1.0) |
| * cpi->last_boost) / 100; |
| |
| } |
| // If there is an active ARF at this location use the minimum |
| // bits on this frame even if it is a contructed arf. |
| // The active maximum quantizer insures that an appropriate |
| // number of bits will be spent if needed for contstructed ARFs. |
| else |
| { |
| cpi->this_frame_target = 0; |
| } |
| |
| cpi->current_gf_interval = cpi->frames_till_gf_update_due; |
| |
| } |
| } |
| } |
| |
| |
| void vp8_update_rate_correction_factors(VP8_COMP *cpi, int damp_var) |
| { |
| int Q = cpi->common.base_qindex; |
| int correction_factor = 100; |
| double rate_correction_factor; |
| double adjustment_limit; |
| |
| int projected_size_based_on_q = 0; |
| |
| // Clear down mmx registers to allow floating point in what follows |
| vp8_clear_system_state(); //__asm emms; |
| |
| if (cpi->common.frame_type == KEY_FRAME) |
| { |
| rate_correction_factor = cpi->key_frame_rate_correction_factor; |
| } |
| else |
| { |
| if (cpi->common.refresh_alt_ref_frame || cpi->common.refresh_golden_frame) |
| rate_correction_factor = cpi->gf_rate_correction_factor; |
| else |
| rate_correction_factor = cpi->rate_correction_factor; |
| } |
| |
| // 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 = |
| (int)(((.5 + rate_correction_factor * |
| vp8_bits_per_mb(cpi->common.frame_type, Q)) * |
| cpi->common.MBs) / (1 << BPER_MB_NORMBITS)); |
| |
| // Make some allowance for cpi->zbin_over_quant |
| if (cpi->zbin_over_quant > 0) |
| { |
| int Z = cpi->zbin_over_quant; |
| double Factor = 0.99; |
| double factor_adjustment = 0.01 / 256.0; //(double)ZBIN_OQ_MAX; |
| |
| while (Z > 0) |
| { |
| Z --; |
| projected_size_based_on_q = |
| (int)(Factor * projected_size_based_on_q); |
| Factor += factor_adjustment; |
| |
| if (Factor >= 0.999) |
| Factor = 0.999; |
| } |
| } |
| |
| // Work out a size correction factor. |
| //if ( cpi->this_frame_target > 0 ) |
| // correction_factor = (100 * cpi->projected_frame_size) / cpi->this_frame_target; |
| if (projected_size_based_on_q > 0) |
| correction_factor = (100 * cpi->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) && (Q < cpi->active_worst_quality) ) |
| if (correction_factor > 102) |
| { |
| // We are not already at the worst allowable quality |
| correction_factor = (int)(100.5 + ((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) && (Q > cpi->active_best_quality) ) |
| else if (correction_factor < 99) |
| { |
| // We are not already at the best allowable quality |
| correction_factor = (int)(100.5 - ((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; |
| } |
| |
| if (cpi->common.frame_type == KEY_FRAME) |
| cpi->key_frame_rate_correction_factor = rate_correction_factor; |
| else |
| { |
| if (cpi->common.refresh_alt_ref_frame || cpi->common.refresh_golden_frame) |
| cpi->gf_rate_correction_factor = rate_correction_factor; |
| else |
| cpi->rate_correction_factor = rate_correction_factor; |
| } |
| } |
| |
| |
| int vp8_regulate_q(VP8_COMP *cpi, int target_bits_per_frame) |
| { |
| int Q = cpi->active_worst_quality; |
| |
| // Reset Zbin OQ value |
| cpi->zbin_over_quant = 0; |
| |
| if (cpi->oxcf.fixed_q >= 0) |
| { |
| Q = cpi->oxcf.fixed_q; |
| |
| if (cpi->common.frame_type == KEY_FRAME) |
| { |
| Q = cpi->oxcf.key_q; |
| } |
| else if (cpi->common.refresh_alt_ref_frame) |
| { |
| Q = cpi->oxcf.alt_q; |
| } |
| else if (cpi->common.refresh_golden_frame) |
| { |
| Q = cpi->oxcf.gold_q; |
| } |
| |
| } |
| else |
| { |
| int i; |
| int last_error = INT_MAX; |
| int target_bits_per_mb; |
| int bits_per_mb_at_this_q; |
| double correction_factor; |
| |
| // Select the appropriate correction factor based upon type of frame. |
| if (cpi->common.frame_type == KEY_FRAME) |
| correction_factor = cpi->key_frame_rate_correction_factor; |
| else |
| { |
| if (cpi->common.refresh_alt_ref_frame || cpi->common.refresh_golden_frame) |
| correction_factor = cpi->gf_rate_correction_factor; |
| else |
| correction_factor = cpi->rate_correction_factor; |
| } |
| |
| // Calculate required scaling factor based on target frame size and size of frame produced using previous Q |
| if (target_bits_per_frame >= (INT_MAX >> BPER_MB_NORMBITS)) |
| target_bits_per_mb = (target_bits_per_frame / cpi->common.MBs) << BPER_MB_NORMBITS; // Case where we would overflow int |
| else |
| target_bits_per_mb = (target_bits_per_frame << BPER_MB_NORMBITS) / cpi->common.MBs; |
| |
| i = cpi->active_best_quality; |
| |
| do |
| { |
| bits_per_mb_at_this_q = |
| (int)(.5 + correction_factor * |
| vp8_bits_per_mb(cpi->common.frame_type, i )); |
| |
| 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 <= cpi->active_worst_quality); |
| |
| |
| // If we are at MAXQ then enable Q over-run which seeks to claw back additional bits through things like |
| // the RD multiplier and zero bin size. |
| if (Q >= MAXQ) |
| { |
| int zbin_oqmax; |
| |
| double Factor = 0.99; |
| double factor_adjustment = 0.01 / 256.0; //(double)ZBIN_OQ_MAX; |
| |
| if (cpi->common.frame_type == KEY_FRAME) |
| zbin_oqmax = 0; //ZBIN_OQ_MAX/16 |
| else if (cpi->common.refresh_alt_ref_frame || (cpi->common.refresh_golden_frame && !cpi->source_alt_ref_active)) |
| zbin_oqmax = 16; |
| else |
| zbin_oqmax = ZBIN_OQ_MAX; |
| |
| /*{ |
| double Factor = (double)target_bits_per_mb/(double)bits_per_mb_at_this_q; |
| double Oq; |
| |
| Factor = Factor/1.2683; |
| |
| Oq = pow( Factor, (1.0/-0.165) ); |
| |
| if ( Oq > zbin_oqmax ) |
| Oq = zbin_oqmax; |
| |
| cpi->zbin_over_quant = (int)Oq; |
| }*/ |
| |
| // Each incrment in the zbin is assumed to have a fixed effect on bitrate. This is not of course true. |
| // The effect will be highly clip dependent and may well have sudden steps. |
| // The idea here is to acheive higher effective quantizers than the normal maximum by expanding the zero |
| // bin and hence decreasing the number of low magnitude non zero coefficients. |
| while (cpi->zbin_over_quant < zbin_oqmax) |
| { |
| cpi->zbin_over_quant ++; |
| |
| if (cpi->zbin_over_quant > zbin_oqmax) |
| cpi->zbin_over_quant = zbin_oqmax; |
| |
| // Adjust bits_per_mb_at_this_q estimate |
| bits_per_mb_at_this_q = (int)(Factor * bits_per_mb_at_this_q); |
| Factor += factor_adjustment; |
| |
| if (Factor >= 0.999) |
| Factor = 0.999; |
| |
| if (bits_per_mb_at_this_q <= target_bits_per_mb) // Break out if we get down to the target rate |
| break; |
| } |
| |
| } |
| } |
| |
| return Q; |
| } |
| |
| |
| static int estimate_keyframe_frequency(VP8_COMP *cpi) |
| { |
| int i; |
| |
| // Average key frame frequency |
| int av_key_frame_frequency = 0; |
| |
| /* First key frame at start of sequence is a special case. We have no |
| * frequency data. |
| */ |
| if (cpi->key_frame_count == 1) |
| { |
| /* Assume a default of 1 kf every 2 seconds, or the max kf interval, |
| * whichever is smaller. |
| */ |
| int key_freq = cpi->oxcf.key_freq>0 ? cpi->oxcf.key_freq : 1; |
| av_key_frame_frequency = (int)cpi->output_frame_rate * 2; |
| |
| if (cpi->oxcf.auto_key && av_key_frame_frequency > key_freq) |
| av_key_frame_frequency = cpi->oxcf.key_freq; |
| |
| cpi->prior_key_frame_distance[KEY_FRAME_CONTEXT - 1] |
| = av_key_frame_frequency; |
| } |
| else |
| { |
| unsigned int total_weight = 0; |
| int last_kf_interval = |
| (cpi->frames_since_key > 0) ? cpi->frames_since_key : 1; |
| |
| /* reset keyframe context and calculate weighted average of last |
| * KEY_FRAME_CONTEXT keyframes |
| */ |
| for (i = 0; i < KEY_FRAME_CONTEXT; i++) |
| { |
| if (i < KEY_FRAME_CONTEXT - 1) |
| cpi->prior_key_frame_distance[i] |
| = cpi->prior_key_frame_distance[i+1]; |
| else |
| cpi->prior_key_frame_distance[i] = last_kf_interval; |
| |
| av_key_frame_frequency += prior_key_frame_weight[i] |
| * cpi->prior_key_frame_distance[i]; |
| total_weight += prior_key_frame_weight[i]; |
| } |
| |
| av_key_frame_frequency /= total_weight; |
| |
| } |
| return av_key_frame_frequency; |
| } |
| |
| |
| void vp8_adjust_key_frame_context(VP8_COMP *cpi) |
| { |
| // Clear down mmx registers to allow floating point in what follows |
| vp8_clear_system_state(); |
| |
| // Do we have any key frame overspend to recover? |
| // Two-pass overspend handled elsewhere. |
| if ((cpi->pass != 2) |
| && (cpi->projected_frame_size > cpi->per_frame_bandwidth)) |
| { |
| int overspend; |
| |
| /* Update the count of key frame overspend to be recovered in |
| * subsequent frames. A portion of the KF overspend is treated as gf |
| * overspend (and hence recovered more quickly) as the kf is also a |
| * gf. Otherwise the few frames following each kf tend to get more |
| * bits allocated than those following other gfs. |
| */ |
| overspend = (cpi->projected_frame_size - cpi->per_frame_bandwidth); |
| cpi->kf_overspend_bits += overspend * 7 / 8; |
| cpi->gf_overspend_bits += overspend * 1 / 8; |
| |
| /* Work out how much to try and recover per frame. */ |
| cpi->kf_bitrate_adjustment = cpi->kf_overspend_bits |
| / estimate_keyframe_frequency(cpi); |
| } |
| |
| cpi->frames_since_key = 0; |
| cpi->key_frame_count++; |
| } |
| |
| |
| void vp8_compute_frame_size_bounds(VP8_COMP *cpi, int *frame_under_shoot_limit, int *frame_over_shoot_limit) |
| { |
| // Set-up bounds on acceptable frame size: |
| if (cpi->oxcf.fixed_q >= 0) |
| { |
| // Fixed Q scenario: frame size never outranges target (there is no target!) |
| *frame_under_shoot_limit = 0; |
| *frame_over_shoot_limit = INT_MAX; |
| } |
| else |
| { |
| if (cpi->common.frame_type == KEY_FRAME) |
| { |
| *frame_over_shoot_limit = cpi->this_frame_target * 9 / 8; |
| *frame_under_shoot_limit = cpi->this_frame_target * 7 / 8; |
| } |
| else |
| { |
| if (cpi->common.refresh_alt_ref_frame || cpi->common.refresh_golden_frame) |
| { |
| *frame_over_shoot_limit = cpi->this_frame_target * 9 / 8; |
| *frame_under_shoot_limit = cpi->this_frame_target * 7 / 8; |
| } |
| else |
| { |
| // For CBR take buffer fullness into account |
| if (cpi->oxcf.end_usage == USAGE_STREAM_FROM_SERVER) |
| { |
| if (cpi->buffer_level >= ((cpi->oxcf.optimal_buffer_level + cpi->oxcf.maximum_buffer_size) >> 1)) |
| { |
| // Buffer is too full so relax overshoot and tighten undershoot |
| *frame_over_shoot_limit = cpi->this_frame_target * 12 / 8; |
| *frame_under_shoot_limit = cpi->this_frame_target * 6 / 8; |
| } |
| else if (cpi->buffer_level <= (cpi->oxcf.optimal_buffer_level >> 1)) |
| { |
| // Buffer is too low so relax undershoot and tighten overshoot |
| *frame_over_shoot_limit = cpi->this_frame_target * 10 / 8; |
| *frame_under_shoot_limit = cpi->this_frame_target * 4 / 8; |
| } |
| else |
| { |
| *frame_over_shoot_limit = cpi->this_frame_target * 11 / 8; |
| *frame_under_shoot_limit = cpi->this_frame_target * 5 / 8; |
| } |
| } |
| // VBR and CQ mode |
| // Note that tighter restrictions here can help quality but hurt encode speed |
| else |
| { |
| // Stron overshoot limit for constrained quality |
| if (cpi->oxcf.end_usage == USAGE_CONSTRAINED_QUALITY) |
| { |
| *frame_over_shoot_limit = cpi->this_frame_target * 11 / 8; |
| *frame_under_shoot_limit = cpi->this_frame_target * 2 / 8; |
| } |
| else |
| { |
| *frame_over_shoot_limit = cpi->this_frame_target * 11 / 8; |
| *frame_under_shoot_limit = cpi->this_frame_target * 5 / 8; |
| } |
| } |
| } |
| } |
| |
| // For very small rate targets where the fractional adjustment |
| // (eg * 7/8) may be tiny make sure there is at least a minimum |
| // range. |
| *frame_over_shoot_limit += 200; |
| *frame_under_shoot_limit -= 200; |
| if ( *frame_under_shoot_limit < 0 ) |
| *frame_under_shoot_limit = 0; |
| } |
| } |
| |
| |
| // return of 0 means drop frame |
| int vp8_pick_frame_size(VP8_COMP *cpi) |
| { |
| VP8_COMMON *cm = &cpi->common; |
| |
| if (cm->frame_type == KEY_FRAME) |
| calc_iframe_target_size(cpi); |
| else |
| { |
| calc_pframe_target_size(cpi); |
| |
| // Check if we're dropping the frame: |
| if (cpi->drop_frame) |
| { |
| cpi->drop_frame = FALSE; |
| cpi->drop_count++; |
| return 0; |
| } |
| } |
| return 1; |
| } |
