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vpx/vp8/encoder/ratectrl.c
Marco Paniconi ef4a9670a8 Remove the resetting of qp params for temporal layers. 
The ambient qp and active worse/best qp were reset for every frame
when temporal layers is on. This change removes this reset.

As this affects the target size for forced key frames
(it will actually lower the size somewhat), we increased the
inital boost factor to compensate.

Change-Id: Ie38d95f5c99ab3d447469c49e2177bc3fcc4ad28
2012-07-27 17:27:32 -07:00

1537 lines
54 KiB
C
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/*
* 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 0.01
#define MAX_BPB_FACTOR 50
extern const MB_PREDICTION_MODE vp8_mode_order[MAX_MODES];
#ifdef MODE_STATS
extern int y_modes[5];
extern int uv_modes[4];
extern int b_modes[10];
extern int inter_y_modes[10];
extern int inter_uv_modes[4];
extern int inter_b_modes[10];
#endif
/* Bits Per MB at different Q (Multiplied by 512) */
#define BPER_MB_NORMBITS 9
/* Work in progress recalibration of baseline rate tables based on
* the assumption that bits per mb is inversely proportional to the
* quantizer value.
*/
const int vp8_bits_per_mb[2][QINDEX_RANGE] =
{
/* Intra case 450000/Qintra */
{
1125000,900000, 750000, 642857, 562500, 500000, 450000, 450000,
409090, 375000, 346153, 321428, 300000, 281250, 264705, 264705,
250000, 236842, 225000, 225000, 214285, 214285, 204545, 204545,
195652, 195652, 187500, 180000, 180000, 173076, 166666, 160714,
155172, 150000, 145161, 140625, 136363, 132352, 128571, 125000,
121621, 121621, 118421, 115384, 112500, 109756, 107142, 104651,
102272, 100000, 97826, 97826, 95744, 93750, 91836, 90000,
88235, 86538, 84905, 83333, 81818, 80357, 78947, 77586,
76271, 75000, 73770, 72580, 71428, 70312, 69230, 68181,
67164, 66176, 65217, 64285, 63380, 62500, 61643, 60810,
60000, 59210, 59210, 58441, 57692, 56962, 56250, 55555,
54878, 54216, 53571, 52941, 52325, 51724, 51136, 50561,
49450, 48387, 47368, 46875, 45918, 45000, 44554, 44117,
43269, 42452, 41666, 40909, 40178, 39473, 38793, 38135,
36885, 36290, 35714, 35156, 34615, 34090, 33582, 33088,
32608, 32142, 31468, 31034, 30405, 29801, 29220, 28662,
},
/* Inter case 285000/Qinter */
{
712500, 570000, 475000, 407142, 356250, 316666, 285000, 259090,
237500, 219230, 203571, 190000, 178125, 167647, 158333, 150000,
142500, 135714, 129545, 123913, 118750, 114000, 109615, 105555,
101785, 98275, 95000, 91935, 89062, 86363, 83823, 81428,
79166, 77027, 75000, 73076, 71250, 69512, 67857, 66279,
64772, 63333, 61956, 60638, 59375, 58163, 57000, 55882,
54807, 53773, 52777, 51818, 50892, 50000, 49137, 47500,
45967, 44531, 43181, 41911, 40714, 39583, 38513, 37500,
36538, 35625, 34756, 33928, 33139, 32386, 31666, 30978,
30319, 29687, 29081, 28500, 27941, 27403, 26886, 26388,
25909, 25446, 25000, 24568, 23949, 23360, 22800, 22265,
21755, 21268, 20802, 20357, 19930, 19520, 19127, 18750,
18387, 18037, 17701, 17378, 17065, 16764, 16473, 16101,
15745, 15405, 15079, 14766, 14467, 14179, 13902, 13636,
13380, 13133, 12895, 12666, 12445, 12179, 11924, 11632,
11445, 11220, 11003, 10795, 10594, 10401, 10215, 10035,
}
};
static const int kf_boost_qadjustment[QINDEX_RANGE] =
{
128, 129, 130, 131, 132, 133, 134, 135,
136, 137, 138, 139, 140, 141, 142, 143,
144, 145, 146, 147, 148, 149, 150, 151,
152, 153, 154, 155, 156, 157, 158, 159,
160, 161, 162, 163, 164, 165, 166, 167,
168, 169, 170, 171, 172, 173, 174, 175,
176, 177, 178, 179, 180, 181, 182, 183,
184, 185, 186, 187, 188, 189, 190, 191,
192, 193, 194, 195, 196, 197, 198, 199,
200, 200, 201, 201, 202, 203, 203, 203,
204, 204, 205, 205, 206, 206, 207, 207,
208, 208, 209, 209, 210, 210, 211, 211,
212, 212, 213, 213, 214, 214, 215, 215,
216, 216, 217, 217, 218, 218, 219, 219,
220, 220, 220, 220, 220, 220, 220, 220,
220, 220, 220, 220, 220, 220, 220, 220,
};
/* #define GFQ_ADJUSTMENT (Q+100) */
#define GFQ_ADJUSTMENT vp8_gf_boost_qadjustment[Q]
const int vp8_gf_boost_qadjustment[QINDEX_RANGE] =
{
80, 82, 84, 86, 88, 90, 92, 94,
96, 97, 98, 99, 100, 101, 102, 103,
104, 105, 106, 107, 108, 109, 110, 111,
112, 113, 114, 115, 116, 117, 118, 119,
120, 121, 122, 123, 124, 125, 126, 127,
128, 129, 130, 131, 132, 133, 134, 135,
136, 137, 138, 139, 140, 141, 142, 143,
144, 145, 146, 147, 148, 149, 150, 151,
152, 153, 154, 155, 156, 157, 158, 159,
160, 161, 162, 163, 164, 165, 166, 167,
168, 169, 170, 171, 172, 173, 174, 175,
176, 177, 178, 179, 180, 181, 182, 183,
184, 184, 185, 185, 186, 186, 187, 187,
188, 188, 189, 189, 190, 190, 191, 191,
192, 192, 193, 193, 194, 194, 194, 194,
195, 195, 196, 196, 197, 197, 198, 198
};
/*
const int vp8_gf_boost_qadjustment[QINDEX_RANGE] =
{
100,101,102,103,104,105,105,106,
106,107,107,108,109,109,110,111,
112,113,114,115,116,117,118,119,
120,121,122,123,124,125,126,127,
128,129,130,131,132,133,134,135,
136,137,138,139,140,141,142,143,
144,145,146,147,148,149,150,151,
152,153,154,155,156,157,158,159,
160,161,162,163,164,165,166,167,
168,169,170,170,171,171,172,172,
173,173,173,174,174,174,175,175,
175,176,176,176,177,177,177,177,
178,178,179,179,180,180,181,181,
182,182,183,183,184,184,185,185,
186,186,187,187,188,188,189,189,
190,190,191,191,192,192,193,193,
};
*/
static const int kf_gf_boost_qlimits[QINDEX_RANGE] =
{
150, 155, 160, 165, 170, 175, 180, 185,
190, 195, 200, 205, 210, 215, 220, 225,
230, 235, 240, 245, 250, 255, 260, 265,
270, 275, 280, 285, 290, 295, 300, 305,
310, 320, 330, 340, 350, 360, 370, 380,
390, 400, 410, 420, 430, 440, 450, 460,
470, 480, 490, 500, 510, 520, 530, 540,
550, 560, 570, 580, 590, 600, 600, 600,
600, 600, 600, 600, 600, 600, 600, 600,
600, 600, 600, 600, 600, 600, 600, 600,
600, 600, 600, 600, 600, 600, 600, 600,
600, 600, 600, 600, 600, 600, 600, 600,
600, 600, 600, 600, 600, 600, 600, 600,
600, 600, 600, 600, 600, 600, 600, 600,
600, 600, 600, 600, 600, 600, 600, 600,
600, 600, 600, 600, 600, 600, 600, 600,
};
/* % 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 };
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->rd_costs.mvcosts);
vp8_copy(cc->ymode_prob, cpi->common.fc.ymode_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->rd_costs.mvcosts, cc->mvcosts);
vp8_copy(cpi->common.fc.ymode_prob, cc->ymode_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);
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);
}
/* initialize pre_mvc to all zero. */
vpx_memset(cpi->common.fc.pre_mvc, 0, sizeof(cpi->common.fc.pre_mvc));
/* Make sure we initialize separate contexts for altref,gold, and normal.
* TODO shouldn't need 3 different copies of structure to do this!
*/
vpx_memcpy(&cpi->lfc_a, &cpi->common.fc, sizeof(cpi->common.fc));
vpx_memcpy(&cpi->lfc_g, &cpi->common.fc, sizeof(cpi->common.fc));
vpx_memcpy(&cpi->lfc_n, &cpi->common.fc, sizeof(cpi->common.fc));
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 = cpi->baseline_gf_interval;
else
cpi->frames_till_gf_update_due = DEFAULT_GF_INTERVAL;
cpi->common.refresh_golden_frame = 1;
cpi->common.refresh_alt_ref_frame = 1;
}
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;
unsigned int target;
/* Clear down mmx registers to allow floating point in what follows */
vp8_clear_system_state();
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;
int initial_boost = 32; /* |3.0 * per_frame_bandwidth| */
/* Boost depends somewhat on frame rate: only used for 1 layer case. */
if (cpi->oxcf.number_of_layers == 1) {
kf_boost = MAX(initial_boost, (int)(2 * cpi->output_frame_rate - 16));
}
else {
/* Initial factor: set target size to: |3.0 * per_frame_bandwidth|. */
kf_boost = initial_boost;
}
/* adjustment up based on q: this factor ranges from ~1.2 to 2.2. */
kf_boost = kf_boost * kf_boost_qadjustment[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));
/* Minimal target size is |2* per_frame_bandwidth|. */
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;
#if 0
{
FILE *f;
f = fopen("kf_boost.stt", "a");
fprintf(f, " %8u %10d %10d %10d\n",
cpi->common.current_video_frame, cpi->gfu_boost, cpi->baseline_gf_interval, cpi->source_alt_ref_pending);
fclose(f);
}
#endif
}
/* Do the best we can to define the parameters 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);
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 (0)
{
}
/* 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 = GFQ_ADJUSTMENT;
/* 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 */
if (Boost > kf_gf_boost_qlimits[Q] && (cpi->pass == 0))
Boost = kf_gf_boost_qlimits[Q];
/* 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 = 0;
/*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 = 1;
else
cpi->source_alt_ref_pending = 0;
}*/
}
}
static void calc_pframe_target_size(VP8_COMP *cpi)
{
int min_frame_target;
int Adjustment;
int old_per_frame_bandwidth = cpi->per_frame_bandwidth;
if ( cpi->current_layer > 0)
cpi->per_frame_bandwidth =
cpi->layer_context[cpi->current_layer].avg_frame_size_for_layer;
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) && (cpi->oxcf.number_of_layers == 1))
{
if (cpi->pass == 2)
{
/* Per frame bit target for the alt ref frame */
cpi->per_frame_bandwidth = cpi->twopass.gf_bits;
cpi->this_frame_target = cpi->per_frame_bandwidth;
}
/* One Pass ??? TBD */
}
/* 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 constraints is important to
* the end usage 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 && cpi->ni_frames > 150)
{
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 constraints
* 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 buffer level.
*/
if (cpi->auto_worst_q && cpi->ni_frames > 150)
{
/* 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;
if(cpi->active_worst_quality > 127)
cpi->active_worst_quality = 127;
}
/* 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->oxcf.end_usage == USAGE_STREAM_FROM_SERVER) &&
((cpi->common.frame_type != KEY_FRAME)))
{
/* 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
cpi->drop_frame = 1;
/* Update the buffer level variable. */
cpi->bits_off_target += cpi->av_per_frame_bandwidth;
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;
}
}
/* 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 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);
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 = 1;
/* Two pass GF descision */
else if (cpi->pass == 2)
cpi->common.refresh_golden_frame = 1;
}
#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, GFQ_ADJUSTMENT, cpi->gfu_boost, gf_frame_useage);
fclose(f);
}
#endif
if (cpi->common.refresh_golden_frame == 1)
{
#if 0
if (0)
{
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)
{
/* The spend on the GF is defined in the two pass
* code for two pass encodes
*/
cpi->this_frame_target = cpi->per_frame_bandwidth;
}
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;
}
}
cpi->per_frame_bandwidth = old_per_frame_bandwidth;
}
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();
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;
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 (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)
{
/* 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)
{
/* 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))
/* Case where we would overflow int */
target_bits_per_mb = (target_bits_per_frame / cpi->common.MBs) << BPER_MB_NORMBITS;
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;
if (cpi->common.frame_type == KEY_FRAME)
zbin_oqmax = 0;
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;
/* Break out if we get down to the target rate */
if (bits_per_mb_at_this_q <= target_bits_per_mb)
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);
if (cpi->oxcf.number_of_layers > 1)
cpi->kf_overspend_bits += overspend;
else
{
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->oxcf.number_of_layers > 1 ||
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 = 0;
return 0;
}
}
return 1;
}
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