ref: 18e9caad47b87450c456713a4801f44e7d2d79c6
dir: /vp9/encoder/vp9_firstpass.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 <limits.h>
#include <math.h>
#include <stdio.h>
#include "./vpx_scale_rtcd.h"
#include "vpx_mem/vpx_mem.h"
#include "vpx_scale/vpx_scale.h"
#include "vpx_scale/yv12config.h"
#include "vp9/common/vp9_entropymv.h"
#include "vp9/common/vp9_quant_common.h"
#include "vp9/common/vp9_reconinter.h" // vp9_setup_dst_planes()
#include "vp9/common/vp9_systemdependent.h"
#include "vp9/encoder/vp9_aq_variance.h"
#include "vp9/encoder/vp9_block.h"
#include "vp9/encoder/vp9_encodeframe.h"
#include "vp9/encoder/vp9_encodemb.h"
#include "vp9/encoder/vp9_encodemv.h"
#include "vp9/encoder/vp9_encoder.h"
#include "vp9/encoder/vp9_extend.h"
#include "vp9/encoder/vp9_firstpass.h"
#include "vp9/encoder/vp9_mcomp.h"
#include "vp9/encoder/vp9_quantize.h"
#include "vp9/encoder/vp9_ratectrl.h"
#include "vp9/encoder/vp9_rdopt.h"
#include "vp9/encoder/vp9_variance.h"
#define OUTPUT_FPF 0
#define IIFACTOR 12.5
#define IIKFACTOR1 12.5
#define IIKFACTOR2 15.0
#define RMAX 512.0
#define GF_RMAX 96.0
#define ERR_DIVISOR 150.0
#define MIN_DECAY_FACTOR 0.1
#define KF_MB_INTRA_MIN 150
#define GF_MB_INTRA_MIN 100
#define DOUBLE_DIVIDE_CHECK(x) ((x) < 0 ? (x) - 0.000001 : (x) + 0.000001)
#define MIN_KF_BOOST 300
#if CONFIG_MULTIPLE_ARF
// Set MIN_GF_INTERVAL to 1 for the full decomposition.
#define MIN_GF_INTERVAL 2
#else
#define MIN_GF_INTERVAL 4
#endif
// #define LONG_TERM_VBR_CORRECTION
static void swap_yv12(YV12_BUFFER_CONFIG *a, YV12_BUFFER_CONFIG *b) {
YV12_BUFFER_CONFIG temp = *a;
*a = *b;
*b = temp;
}
static int gfboost_qadjust(int qindex) {
const double q = vp9_convert_qindex_to_q(qindex);
return (int)((0.00000828 * q * q * q) +
(-0.0055 * q * q) +
(1.32 * q) + 79.3);
}
// Resets the first pass file to the given position using a relative seek from
// the current position.
static void reset_fpf_position(struct twopass_rc *p,
const FIRSTPASS_STATS *position) {
p->stats_in = position;
}
static int lookup_next_frame_stats(const struct twopass_rc *p,
FIRSTPASS_STATS *next_frame) {
if (p->stats_in >= p->stats_in_end)
return EOF;
*next_frame = *p->stats_in;
return 1;
}
// Read frame stats at an offset from the current position.
static int read_frame_stats(const struct twopass_rc *p,
FIRSTPASS_STATS *frame_stats, int offset) {
const FIRSTPASS_STATS *fps_ptr = p->stats_in;
// Check legality of offset.
if (offset >= 0) {
if (&fps_ptr[offset] >= p->stats_in_end)
return EOF;
} else if (offset < 0) {
if (&fps_ptr[offset] < p->stats_in_start)
return EOF;
}
*frame_stats = fps_ptr[offset];
return 1;
}
static int input_stats(struct twopass_rc *p, FIRSTPASS_STATS *fps) {
if (p->stats_in >= p->stats_in_end)
return EOF;
*fps = *p->stats_in;
++p->stats_in;
return 1;
}
static void output_stats(FIRSTPASS_STATS *stats,
struct vpx_codec_pkt_list *pktlist) {
struct vpx_codec_cx_pkt pkt;
pkt.kind = VPX_CODEC_STATS_PKT;
pkt.data.twopass_stats.buf = stats;
pkt.data.twopass_stats.sz = sizeof(FIRSTPASS_STATS);
vpx_codec_pkt_list_add(pktlist, &pkt);
// TEMP debug code
#if OUTPUT_FPF
{
FILE *fpfile;
fpfile = fopen("firstpass.stt", "a");
fprintf(fpfile, "%12.0f %12.0f %12.0f %12.0f %12.0f %12.4f %12.4f"
"%12.4f %12.4f %12.4f %12.4f %12.4f %12.4f %12.4f"
"%12.0f %12.0f %12.4f %12.0f %12.0f %12.4f\n",
stats->frame,
stats->intra_error,
stats->coded_error,
stats->sr_coded_error,
stats->ssim_weighted_pred_err,
stats->pcnt_inter,
stats->pcnt_motion,
stats->pcnt_second_ref,
stats->pcnt_neutral,
stats->MVr,
stats->mvr_abs,
stats->MVc,
stats->mvc_abs,
stats->MVrv,
stats->MVcv,
stats->mv_in_out_count,
stats->new_mv_count,
stats->count,
stats->duration);
fclose(fpfile);
}
#endif
}
static void zero_stats(FIRSTPASS_STATS *section) {
section->frame = 0.0;
section->intra_error = 0.0;
section->coded_error = 0.0;
section->sr_coded_error = 0.0;
section->ssim_weighted_pred_err = 0.0;
section->pcnt_inter = 0.0;
section->pcnt_motion = 0.0;
section->pcnt_second_ref = 0.0;
section->pcnt_neutral = 0.0;
section->MVr = 0.0;
section->mvr_abs = 0.0;
section->MVc = 0.0;
section->mvc_abs = 0.0;
section->MVrv = 0.0;
section->MVcv = 0.0;
section->mv_in_out_count = 0.0;
section->new_mv_count = 0.0;
section->count = 0.0;
section->duration = 1.0;
section->spatial_layer_id = 0;
}
static void accumulate_stats(FIRSTPASS_STATS *section,
const FIRSTPASS_STATS *frame) {
section->frame += frame->frame;
section->spatial_layer_id = frame->spatial_layer_id;
section->intra_error += frame->intra_error;
section->coded_error += frame->coded_error;
section->sr_coded_error += frame->sr_coded_error;
section->ssim_weighted_pred_err += frame->ssim_weighted_pred_err;
section->pcnt_inter += frame->pcnt_inter;
section->pcnt_motion += frame->pcnt_motion;
section->pcnt_second_ref += frame->pcnt_second_ref;
section->pcnt_neutral += frame->pcnt_neutral;
section->MVr += frame->MVr;
section->mvr_abs += frame->mvr_abs;
section->MVc += frame->MVc;
section->mvc_abs += frame->mvc_abs;
section->MVrv += frame->MVrv;
section->MVcv += frame->MVcv;
section->mv_in_out_count += frame->mv_in_out_count;
section->new_mv_count += frame->new_mv_count;
section->count += frame->count;
section->duration += frame->duration;
}
static void subtract_stats(FIRSTPASS_STATS *section,
const FIRSTPASS_STATS *frame) {
section->frame -= frame->frame;
section->intra_error -= frame->intra_error;
section->coded_error -= frame->coded_error;
section->sr_coded_error -= frame->sr_coded_error;
section->ssim_weighted_pred_err -= frame->ssim_weighted_pred_err;
section->pcnt_inter -= frame->pcnt_inter;
section->pcnt_motion -= frame->pcnt_motion;
section->pcnt_second_ref -= frame->pcnt_second_ref;
section->pcnt_neutral -= frame->pcnt_neutral;
section->MVr -= frame->MVr;
section->mvr_abs -= frame->mvr_abs;
section->MVc -= frame->MVc;
section->mvc_abs -= frame->mvc_abs;
section->MVrv -= frame->MVrv;
section->MVcv -= frame->MVcv;
section->mv_in_out_count -= frame->mv_in_out_count;
section->new_mv_count -= frame->new_mv_count;
section->count -= frame->count;
section->duration -= frame->duration;
}
static void avg_stats(FIRSTPASS_STATS *section) {
if (section->count < 1.0)
return;
section->intra_error /= section->count;
section->coded_error /= section->count;
section->sr_coded_error /= section->count;
section->ssim_weighted_pred_err /= section->count;
section->pcnt_inter /= section->count;
section->pcnt_second_ref /= section->count;
section->pcnt_neutral /= section->count;
section->pcnt_motion /= section->count;
section->MVr /= section->count;
section->mvr_abs /= section->count;
section->MVc /= section->count;
section->mvc_abs /= section->count;
section->MVrv /= section->count;
section->MVcv /= section->count;
section->mv_in_out_count /= section->count;
section->duration /= section->count;
}
// Calculate a modified Error used in distributing bits between easier and
// harder frames.
static double calculate_modified_err(const VP9_COMP *cpi,
const FIRSTPASS_STATS *this_frame) {
const struct twopass_rc *twopass = &cpi->twopass;
const SVC *const svc = &cpi->svc;
const FIRSTPASS_STATS *stats;
double av_err;
double modified_error;
if (svc->number_spatial_layers > 1 &&
svc->number_temporal_layers == 1) {
twopass = &svc->layer_context[svc->spatial_layer_id].twopass;
}
stats = &twopass->total_stats;
av_err = stats->ssim_weighted_pred_err / stats->count;
modified_error = av_err * pow(this_frame->ssim_weighted_pred_err /
DOUBLE_DIVIDE_CHECK(av_err),
cpi->oxcf.two_pass_vbrbias / 100.0);
return fclamp(modified_error,
twopass->modified_error_min, twopass->modified_error_max);
}
static const double weight_table[256] = {
0.020000, 0.020000, 0.020000, 0.020000, 0.020000, 0.020000, 0.020000,
0.020000, 0.020000, 0.020000, 0.020000, 0.020000, 0.020000, 0.020000,
0.020000, 0.020000, 0.020000, 0.020000, 0.020000, 0.020000, 0.020000,
0.020000, 0.020000, 0.020000, 0.020000, 0.020000, 0.020000, 0.020000,
0.020000, 0.020000, 0.020000, 0.020000, 0.020000, 0.031250, 0.062500,
0.093750, 0.125000, 0.156250, 0.187500, 0.218750, 0.250000, 0.281250,
0.312500, 0.343750, 0.375000, 0.406250, 0.437500, 0.468750, 0.500000,
0.531250, 0.562500, 0.593750, 0.625000, 0.656250, 0.687500, 0.718750,
0.750000, 0.781250, 0.812500, 0.843750, 0.875000, 0.906250, 0.937500,
0.968750, 1.000000, 1.000000, 1.000000, 1.000000, 1.000000, 1.000000,
1.000000, 1.000000, 1.000000, 1.000000, 1.000000, 1.000000, 1.000000,
1.000000, 1.000000, 1.000000, 1.000000, 1.000000, 1.000000, 1.000000,
1.000000, 1.000000, 1.000000, 1.000000, 1.000000, 1.000000, 1.000000,
1.000000, 1.000000, 1.000000, 1.000000, 1.000000, 1.000000, 1.000000,
1.000000, 1.000000, 1.000000, 1.000000, 1.000000, 1.000000, 1.000000,
1.000000, 1.000000, 1.000000, 1.000000, 1.000000, 1.000000, 1.000000,
1.000000, 1.000000, 1.000000, 1.000000, 1.000000, 1.000000, 1.000000,
1.000000, 1.000000, 1.000000, 1.000000, 1.000000, 1.000000, 1.000000,
1.000000, 1.000000, 1.000000, 1.000000, 1.000000, 1.000000, 1.000000,
1.000000, 1.000000, 1.000000, 1.000000, 1.000000, 1.000000, 1.000000,
1.000000, 1.000000, 1.000000, 1.000000, 1.000000, 1.000000, 1.000000,
1.000000, 1.000000, 1.000000, 1.000000, 1.000000, 1.000000, 1.000000,
1.000000, 1.000000, 1.000000, 1.000000, 1.000000, 1.000000, 1.000000,
1.000000, 1.000000, 1.000000, 1.000000, 1.000000, 1.000000, 1.000000,
1.000000, 1.000000, 1.000000, 1.000000, 1.000000, 1.000000, 1.000000,
1.000000, 1.000000, 1.000000, 1.000000, 1.000000, 1.000000, 1.000000,
1.000000, 1.000000, 1.000000, 1.000000, 1.000000, 1.000000, 1.000000,
1.000000, 1.000000, 1.000000, 1.000000, 1.000000, 1.000000, 1.000000,
1.000000, 1.000000, 1.000000, 1.000000, 1.000000, 1.000000, 1.000000,
1.000000, 1.000000, 1.000000, 1.000000, 1.000000, 1.000000, 1.000000,
1.000000, 1.000000, 1.000000, 1.000000, 1.000000, 1.000000, 1.000000,
1.000000, 1.000000, 1.000000, 1.000000, 1.000000, 1.000000, 1.000000,
1.000000, 1.000000, 1.000000, 1.000000, 1.000000, 1.000000, 1.000000,
1.000000, 1.000000, 1.000000, 1.000000, 1.000000, 1.000000, 1.000000,
1.000000, 1.000000, 1.000000, 1.000000, 1.000000, 1.000000, 1.000000,
1.000000, 1.000000, 1.000000, 1.000000, 1.000000, 1.000000, 1.000000,
1.000000, 1.000000, 1.000000, 1.000000
};
static double simple_weight(const YV12_BUFFER_CONFIG *buf) {
int i, j;
double sum = 0.0;
const int w = buf->y_crop_width;
const int h = buf->y_crop_height;
const uint8_t *row = buf->y_buffer;
for (i = 0; i < h; ++i) {
const uint8_t *pixel = row;
for (j = 0; j < w; ++j)
sum += weight_table[*pixel++];
row += buf->y_stride;
}
return MAX(0.1, sum / (w * h));
}
// This function returns the maximum target rate per frame.
static int frame_max_bits(const RATE_CONTROL *rc,
const VP9EncoderConfig *oxcf) {
int64_t max_bits = ((int64_t)rc->avg_frame_bandwidth *
(int64_t)oxcf->two_pass_vbrmax_section) / 100;
if (max_bits < 0)
max_bits = 0;
else if (max_bits > rc->max_frame_bandwidth)
max_bits = rc->max_frame_bandwidth;
return (int)max_bits;
}
void vp9_init_first_pass(VP9_COMP *cpi) {
zero_stats(&cpi->twopass.total_stats);
}
void vp9_end_first_pass(VP9_COMP *cpi) {
if (cpi->use_svc && cpi->svc.number_temporal_layers == 1) {
int i;
for (i = 0; i < cpi->svc.number_spatial_layers; ++i) {
output_stats(&cpi->svc.layer_context[i].twopass.total_stats,
cpi->output_pkt_list);
}
} else {
output_stats(&cpi->twopass.total_stats, cpi->output_pkt_list);
}
}
static vp9_variance_fn_t get_block_variance_fn(BLOCK_SIZE bsize) {
switch (bsize) {
case BLOCK_8X8:
return vp9_mse8x8;
case BLOCK_16X8:
return vp9_mse16x8;
case BLOCK_8X16:
return vp9_mse8x16;
default:
return vp9_mse16x16;
}
}
static unsigned int get_prediction_error(BLOCK_SIZE bsize,
const struct buf_2d *src,
const struct buf_2d *ref) {
unsigned int sse;
const vp9_variance_fn_t fn = get_block_variance_fn(bsize);
fn(src->buf, src->stride, ref->buf, ref->stride, &sse);
return sse;
}
// Refine the motion search range according to the frame dimension
// for first pass test.
static int get_search_range(const VP9_COMMON *cm) {
int sr = 0;
const int dim = MIN(cm->width, cm->height);
while ((dim << sr) < MAX_FULL_PEL_VAL)
++sr;
return sr;
}
static void first_pass_motion_search(VP9_COMP *cpi, MACROBLOCK *x,
const MV *ref_mv, MV *best_mv,
int *best_motion_err) {
MACROBLOCKD *const xd = &x->e_mbd;
MV tmp_mv = {0, 0};
MV ref_mv_full = {ref_mv->row >> 3, ref_mv->col >> 3};
int num00, tmp_err, n;
const BLOCK_SIZE bsize = xd->mi[0]->mbmi.sb_type;
vp9_variance_fn_ptr_t v_fn_ptr = cpi->fn_ptr[bsize];
const int new_mv_mode_penalty = 256;
int step_param = 3;
int further_steps = (MAX_MVSEARCH_STEPS - 1) - step_param;
const int sr = get_search_range(&cpi->common);
step_param += sr;
further_steps -= sr;
// Override the default variance function to use MSE.
v_fn_ptr.vf = get_block_variance_fn(bsize);
// Center the initial step/diamond search on best mv.
tmp_err = cpi->diamond_search_sad(x, &cpi->ss_cfg, &ref_mv_full, &tmp_mv,
step_param,
x->sadperbit16, &num00, &v_fn_ptr, ref_mv);
if (tmp_err < INT_MAX)
tmp_err = vp9_get_mvpred_var(x, &tmp_mv, ref_mv, &v_fn_ptr, 1);
if (tmp_err < INT_MAX - new_mv_mode_penalty)
tmp_err += new_mv_mode_penalty;
if (tmp_err < *best_motion_err) {
*best_motion_err = tmp_err;
*best_mv = tmp_mv;
}
// Carry out further step/diamond searches as necessary.
n = num00;
num00 = 0;
while (n < further_steps) {
++n;
if (num00) {
--num00;
} else {
tmp_err = cpi->diamond_search_sad(x, &cpi->ss_cfg, &ref_mv_full, &tmp_mv,
step_param + n, x->sadperbit16,
&num00, &v_fn_ptr, ref_mv);
if (tmp_err < INT_MAX)
tmp_err = vp9_get_mvpred_var(x, &tmp_mv, ref_mv, &v_fn_ptr, 1);
if (tmp_err < INT_MAX - new_mv_mode_penalty)
tmp_err += new_mv_mode_penalty;
if (tmp_err < *best_motion_err) {
*best_motion_err = tmp_err;
*best_mv = tmp_mv;
}
}
}
}
static BLOCK_SIZE get_bsize(const VP9_COMMON *cm, int mb_row, int mb_col) {
if (2 * mb_col + 1 < cm->mi_cols) {
return 2 * mb_row + 1 < cm->mi_rows ? BLOCK_16X16
: BLOCK_16X8;
} else {
return 2 * mb_row + 1 < cm->mi_rows ? BLOCK_8X16
: BLOCK_8X8;
}
}
void vp9_first_pass(VP9_COMP *cpi) {
int mb_row, mb_col;
MACROBLOCK *const x = &cpi->mb;
VP9_COMMON *const cm = &cpi->common;
MACROBLOCKD *const xd = &x->e_mbd;
TileInfo tile;
struct macroblock_plane *const p = x->plane;
struct macroblockd_plane *const pd = xd->plane;
const PICK_MODE_CONTEXT *ctx = &x->pc_root->none;
int i;
int recon_yoffset, recon_uvoffset;
YV12_BUFFER_CONFIG *const lst_yv12 = get_ref_frame_buffer(cpi, LAST_FRAME);
YV12_BUFFER_CONFIG *gld_yv12 = get_ref_frame_buffer(cpi, GOLDEN_FRAME);
YV12_BUFFER_CONFIG *const new_yv12 = get_frame_new_buffer(cm);
int recon_y_stride = lst_yv12->y_stride;
int recon_uv_stride = lst_yv12->uv_stride;
int uv_mb_height = 16 >> (lst_yv12->y_height > lst_yv12->uv_height);
int64_t intra_error = 0;
int64_t coded_error = 0;
int64_t sr_coded_error = 0;
int sum_mvr = 0, sum_mvc = 0;
int sum_mvr_abs = 0, sum_mvc_abs = 0;
int64_t sum_mvrs = 0, sum_mvcs = 0;
int mvcount = 0;
int intercount = 0;
int second_ref_count = 0;
int intrapenalty = 256;
int neutral_count = 0;
int new_mv_count = 0;
int sum_in_vectors = 0;
uint32_t lastmv_as_int = 0;
struct twopass_rc *twopass = &cpi->twopass;
const MV zero_mv = {0, 0};
const YV12_BUFFER_CONFIG *first_ref_buf = lst_yv12;
vp9_clear_system_state();
if (cpi->use_svc && cpi->svc.number_temporal_layers == 1) {
MV_REFERENCE_FRAME ref_frame = LAST_FRAME;
const YV12_BUFFER_CONFIG *scaled_ref_buf = NULL;
twopass = &cpi->svc.layer_context[cpi->svc.spatial_layer_id].twopass;
vp9_scale_references(cpi);
// Use either last frame or alt frame for motion search.
if (cpi->ref_frame_flags & VP9_LAST_FLAG) {
scaled_ref_buf = vp9_get_scaled_ref_frame(cpi, LAST_FRAME);
ref_frame = LAST_FRAME;
} else if (cpi->ref_frame_flags & VP9_ALT_FLAG) {
scaled_ref_buf = vp9_get_scaled_ref_frame(cpi, ALTREF_FRAME);
ref_frame = ALTREF_FRAME;
}
if (scaled_ref_buf != NULL) {
// Update the stride since we are using scaled reference buffer
first_ref_buf = scaled_ref_buf;
recon_y_stride = first_ref_buf->y_stride;
recon_uv_stride = first_ref_buf->uv_stride;
uv_mb_height = 16 >> (first_ref_buf->y_height > first_ref_buf->uv_height);
}
// Disable golden frame for svc first pass for now.
gld_yv12 = NULL;
set_ref_ptrs(cm, xd, ref_frame, NONE);
cpi->Source = vp9_scale_if_required(cm, cpi->un_scaled_source,
&cpi->scaled_source);
}
vp9_setup_src_planes(x, cpi->Source, 0, 0);
vp9_setup_pre_planes(xd, 0, first_ref_buf, 0, 0, NULL);
vp9_setup_dst_planes(xd, new_yv12, 0, 0);
xd->mi = cm->mi_grid_visible;
xd->mi[0] = cm->mi;
vp9_setup_block_planes(&x->e_mbd, cm->subsampling_x, cm->subsampling_y);
vp9_frame_init_quantizer(cpi);
for (i = 0; i < MAX_MB_PLANE; ++i) {
p[i].coeff = ctx->coeff_pbuf[i][1];
p[i].qcoeff = ctx->qcoeff_pbuf[i][1];
pd[i].dqcoeff = ctx->dqcoeff_pbuf[i][1];
p[i].eobs = ctx->eobs_pbuf[i][1];
}
x->skip_recode = 0;
vp9_init_mv_probs(cm);
vp9_initialize_rd_consts(cpi);
// Tiling is ignored in the first pass.
vp9_tile_init(&tile, cm, 0, 0);
for (mb_row = 0; mb_row < cm->mb_rows; ++mb_row) {
int_mv best_ref_mv;
best_ref_mv.as_int = 0;
// Reset above block coeffs.
xd->up_available = (mb_row != 0);
recon_yoffset = (mb_row * recon_y_stride * 16);
recon_uvoffset = (mb_row * recon_uv_stride * uv_mb_height);
// Set up limit values for motion vectors to prevent them extending
// outside the UMV borders.
x->mv_row_min = -((mb_row * 16) + BORDER_MV_PIXELS_B16);
x->mv_row_max = ((cm->mb_rows - 1 - mb_row) * 16)
+ BORDER_MV_PIXELS_B16;
for (mb_col = 0; mb_col < cm->mb_cols; ++mb_col) {
int this_error;
const int use_dc_pred = (mb_col || mb_row) && (!mb_col || !mb_row);
double error_weight = 1.0;
const BLOCK_SIZE bsize = get_bsize(cm, mb_row, mb_col);
vp9_clear_system_state();
xd->plane[0].dst.buf = new_yv12->y_buffer + recon_yoffset;
xd->plane[1].dst.buf = new_yv12->u_buffer + recon_uvoffset;
xd->plane[2].dst.buf = new_yv12->v_buffer + recon_uvoffset;
xd->left_available = (mb_col != 0);
xd->mi[0]->mbmi.sb_type = bsize;
xd->mi[0]->mbmi.ref_frame[0] = INTRA_FRAME;
set_mi_row_col(xd, &tile,
mb_row << 1, num_8x8_blocks_high_lookup[bsize],
mb_col << 1, num_8x8_blocks_wide_lookup[bsize],
cm->mi_rows, cm->mi_cols);
if (cpi->oxcf.aq_mode == VARIANCE_AQ) {
const int energy = vp9_block_energy(cpi, x, bsize);
error_weight = vp9_vaq_inv_q_ratio(energy);
}
// Do intra 16x16 prediction.
x->skip_encode = 0;
xd->mi[0]->mbmi.mode = DC_PRED;
xd->mi[0]->mbmi.tx_size = use_dc_pred ?
(bsize >= BLOCK_16X16 ? TX_16X16 : TX_8X8) : TX_4X4;
vp9_encode_intra_block_plane(x, bsize, 0);
this_error = vp9_get_mb_ss(x->plane[0].src_diff);
if (cpi->oxcf.aq_mode == VARIANCE_AQ) {
vp9_clear_system_state();
this_error = (int)(this_error * error_weight);
}
// Intrapenalty below deals with situations where the intra and inter
// error scores are very low (e.g. a plain black frame).
// We do not have special cases in first pass for 0,0 and nearest etc so
// all inter modes carry an overhead cost estimate for the mv.
// When the error score is very low this causes us to pick all or lots of
// INTRA modes and throw lots of key frames.
// This penalty adds a cost matching that of a 0,0 mv to the intra case.
this_error += intrapenalty;
// Accumulate the intra error.
intra_error += (int64_t)this_error;
// Set up limit values for motion vectors to prevent them extending
// outside the UMV borders.
x->mv_col_min = -((mb_col * 16) + BORDER_MV_PIXELS_B16);
x->mv_col_max = ((cm->mb_cols - 1 - mb_col) * 16) + BORDER_MV_PIXELS_B16;
// Other than for the first frame do a motion search.
if (cm->current_video_frame > 0) {
int tmp_err, motion_error;
int_mv mv, tmp_mv;
xd->plane[0].pre[0].buf = first_ref_buf->y_buffer + recon_yoffset;
motion_error = get_prediction_error(bsize, &x->plane[0].src,
&xd->plane[0].pre[0]);
// Assume 0,0 motion with no mv overhead.
mv.as_int = tmp_mv.as_int = 0;
// Test last reference frame using the previous best mv as the
// starting point (best reference) for the search.
first_pass_motion_search(cpi, x, &best_ref_mv.as_mv, &mv.as_mv,
&motion_error);
if (cpi->oxcf.aq_mode == VARIANCE_AQ) {
vp9_clear_system_state();
motion_error = (int)(motion_error * error_weight);
}
// If the current best reference mv is not centered on 0,0 then do a 0,0
// based search as well.
if (best_ref_mv.as_int) {
tmp_err = INT_MAX;
first_pass_motion_search(cpi, x, &zero_mv, &tmp_mv.as_mv,
&tmp_err);
if (cpi->oxcf.aq_mode == VARIANCE_AQ) {
vp9_clear_system_state();
tmp_err = (int)(tmp_err * error_weight);
}
if (tmp_err < motion_error) {
motion_error = tmp_err;
mv.as_int = tmp_mv.as_int;
}
}
// Search in an older reference frame.
if (cm->current_video_frame > 1 && gld_yv12 != NULL) {
// Assume 0,0 motion with no mv overhead.
int gf_motion_error;
xd->plane[0].pre[0].buf = gld_yv12->y_buffer + recon_yoffset;
gf_motion_error = get_prediction_error(bsize, &x->plane[0].src,
&xd->plane[0].pre[0]);
first_pass_motion_search(cpi, x, &zero_mv, &tmp_mv.as_mv,
&gf_motion_error);
if (cpi->oxcf.aq_mode == VARIANCE_AQ) {
vp9_clear_system_state();
gf_motion_error = (int)(gf_motion_error * error_weight);
}
if (gf_motion_error < motion_error && gf_motion_error < this_error)
++second_ref_count;
// Reset to last frame as reference buffer.
xd->plane[0].pre[0].buf = first_ref_buf->y_buffer + recon_yoffset;
xd->plane[1].pre[0].buf = first_ref_buf->u_buffer + recon_uvoffset;
xd->plane[2].pre[0].buf = first_ref_buf->v_buffer + recon_uvoffset;
// In accumulating a score for the older reference frame take the
// best of the motion predicted score and the intra coded error
// (just as will be done for) accumulation of "coded_error" for
// the last frame.
if (gf_motion_error < this_error)
sr_coded_error += gf_motion_error;
else
sr_coded_error += this_error;
} else {
sr_coded_error += motion_error;
}
// Start by assuming that intra mode is best.
best_ref_mv.as_int = 0;
if (motion_error <= this_error) {
// Keep a count of cases where the inter and intra were very close
// and very low. This helps with scene cut detection for example in
// cropped clips with black bars at the sides or top and bottom.
if (((this_error - intrapenalty) * 9 <= motion_error * 10) &&
this_error < 2 * intrapenalty)
++neutral_count;
mv.as_mv.row *= 8;
mv.as_mv.col *= 8;
this_error = motion_error;
xd->mi[0]->mbmi.mode = NEWMV;
xd->mi[0]->mbmi.mv[0] = mv;
xd->mi[0]->mbmi.tx_size = TX_4X4;
xd->mi[0]->mbmi.ref_frame[0] = LAST_FRAME;
xd->mi[0]->mbmi.ref_frame[1] = NONE;
vp9_build_inter_predictors_sby(xd, mb_row << 1, mb_col << 1, bsize);
vp9_encode_sby_pass1(x, bsize);
sum_mvr += mv.as_mv.row;
sum_mvr_abs += abs(mv.as_mv.row);
sum_mvc += mv.as_mv.col;
sum_mvc_abs += abs(mv.as_mv.col);
sum_mvrs += mv.as_mv.row * mv.as_mv.row;
sum_mvcs += mv.as_mv.col * mv.as_mv.col;
++intercount;
best_ref_mv.as_int = mv.as_int;
if (mv.as_int) {
++mvcount;
// Non-zero vector, was it different from the last non zero vector?
if (mv.as_int != lastmv_as_int)
++new_mv_count;
lastmv_as_int = mv.as_int;
// Does the row vector point inwards or outwards?
if (mb_row < cm->mb_rows / 2) {
if (mv.as_mv.row > 0)
--sum_in_vectors;
else if (mv.as_mv.row < 0)
++sum_in_vectors;
} else if (mb_row > cm->mb_rows / 2) {
if (mv.as_mv.row > 0)
++sum_in_vectors;
else if (mv.as_mv.row < 0)
--sum_in_vectors;
}
// Does the col vector point inwards or outwards?
if (mb_col < cm->mb_cols / 2) {
if (mv.as_mv.col > 0)
--sum_in_vectors;
else if (mv.as_mv.col < 0)
++sum_in_vectors;
} else if (mb_col > cm->mb_cols / 2) {
if (mv.as_mv.col > 0)
++sum_in_vectors;
else if (mv.as_mv.col < 0)
--sum_in_vectors;
}
}
}
} else {
sr_coded_error += (int64_t)this_error;
}
coded_error += (int64_t)this_error;
// Adjust to the next column of MBs.
x->plane[0].src.buf += 16;
x->plane[1].src.buf += uv_mb_height;
x->plane[2].src.buf += uv_mb_height;
recon_yoffset += 16;
recon_uvoffset += uv_mb_height;
}
// Adjust to the next row of MBs.
x->plane[0].src.buf += 16 * x->plane[0].src.stride - 16 * cm->mb_cols;
x->plane[1].src.buf += uv_mb_height * x->plane[1].src.stride -
uv_mb_height * cm->mb_cols;
x->plane[2].src.buf += uv_mb_height * x->plane[1].src.stride -
uv_mb_height * cm->mb_cols;
vp9_clear_system_state();
}
vp9_clear_system_state();
{
FIRSTPASS_STATS fps;
fps.frame = cm->current_video_frame;
fps.spatial_layer_id = cpi->svc.spatial_layer_id;
fps.intra_error = (double)(intra_error >> 8);
fps.coded_error = (double)(coded_error >> 8);
fps.sr_coded_error = (double)(sr_coded_error >> 8);
fps.ssim_weighted_pred_err = fps.coded_error * simple_weight(cpi->Source);
fps.count = 1.0;
fps.pcnt_inter = (double)intercount / cm->MBs;
fps.pcnt_second_ref = (double)second_ref_count / cm->MBs;
fps.pcnt_neutral = (double)neutral_count / cm->MBs;
if (mvcount > 0) {
fps.MVr = (double)sum_mvr / mvcount;
fps.mvr_abs = (double)sum_mvr_abs / mvcount;
fps.MVc = (double)sum_mvc / mvcount;
fps.mvc_abs = (double)sum_mvc_abs / mvcount;
fps.MVrv = ((double)sum_mvrs - (fps.MVr * fps.MVr / mvcount)) / mvcount;
fps.MVcv = ((double)sum_mvcs - (fps.MVc * fps.MVc / mvcount)) / mvcount;
fps.mv_in_out_count = (double)sum_in_vectors / (mvcount * 2);
fps.new_mv_count = new_mv_count;
fps.pcnt_motion = (double)mvcount / cm->MBs;
} else {
fps.MVr = 0.0;
fps.mvr_abs = 0.0;
fps.MVc = 0.0;
fps.mvc_abs = 0.0;
fps.MVrv = 0.0;
fps.MVcv = 0.0;
fps.mv_in_out_count = 0.0;
fps.new_mv_count = 0.0;
fps.pcnt_motion = 0.0;
}
// TODO(paulwilkins): Handle the case when duration is set to 0, or
// something less than the full time between subsequent values of
// cpi->source_time_stamp.
fps.duration = (double)(cpi->source->ts_end - cpi->source->ts_start);
// Don't want to do output stats with a stack variable!
twopass->this_frame_stats = fps;
output_stats(&twopass->this_frame_stats, cpi->output_pkt_list);
accumulate_stats(&twopass->total_stats, &fps);
}
// Copy the previous Last Frame back into gf and and arf buffers if
// the prediction is good enough... but also don't allow it to lag too far.
if ((twopass->sr_update_lag > 3) ||
((cm->current_video_frame > 0) &&
(twopass->this_frame_stats.pcnt_inter > 0.20) &&
((twopass->this_frame_stats.intra_error /
DOUBLE_DIVIDE_CHECK(twopass->this_frame_stats.coded_error)) > 2.0))) {
if (gld_yv12 != NULL) {
vp8_yv12_copy_frame(lst_yv12, gld_yv12);
}
twopass->sr_update_lag = 1;
} else {
++twopass->sr_update_lag;
}
vp9_extend_frame_borders(new_yv12);
if (cpi->use_svc && cpi->svc.number_temporal_layers == 1) {
vp9_update_reference_frames(cpi);
} else {
// Swap frame pointers so last frame refers to the frame we just compressed.
swap_yv12(lst_yv12, new_yv12);
}
// Special case for the first frame. Copy into the GF buffer as a second
// reference.
if (cm->current_video_frame == 0 && gld_yv12 != NULL) {
vp8_yv12_copy_frame(lst_yv12, gld_yv12);
}
// Use this to see what the first pass reconstruction looks like.
if (0) {
char filename[512];
FILE *recon_file;
snprintf(filename, sizeof(filename), "enc%04d.yuv",
(int)cm->current_video_frame);
if (cm->current_video_frame == 0)
recon_file = fopen(filename, "wb");
else
recon_file = fopen(filename, "ab");
(void)fwrite(lst_yv12->buffer_alloc, lst_yv12->frame_size, 1, recon_file);
fclose(recon_file);
}
++cm->current_video_frame;
}
static double calc_correction_factor(double err_per_mb,
double err_divisor,
double pt_low,
double pt_high,
int q) {
const double error_term = err_per_mb / err_divisor;
// Adjustment based on actual quantizer to power term.
const double power_term = MIN(vp9_convert_qindex_to_q(q) * 0.0125 + pt_low,
pt_high);
// Calculate correction factor.
if (power_term < 1.0)
assert(error_term >= 0.0);
return fclamp(pow(error_term, power_term), 0.05, 5.0);
}
static int get_twopass_worst_quality(const VP9_COMP *cpi,
const FIRSTPASS_STATS *stats,
int section_target_bandwidth) {
const RATE_CONTROL *const rc = &cpi->rc;
const VP9EncoderConfig *const oxcf = &cpi->oxcf;
if (section_target_bandwidth <= 0) {
return rc->worst_quality; // Highest value allowed
} else {
const int num_mbs = cpi->common.MBs;
const double section_err = stats->coded_error / stats->count;
const double err_per_mb = section_err / num_mbs;
const double speed_term = 1.0 + 0.04 * oxcf->speed;
const int target_norm_bits_per_mb = ((uint64_t)section_target_bandwidth <<
BPER_MB_NORMBITS) / num_mbs;
int q;
int is_svc_upper_layer = 0;
if (cpi->use_svc && cpi->svc.number_temporal_layers == 1 &&
cpi->svc.spatial_layer_id > 0) {
is_svc_upper_layer = 1;
}
// Try and pick a max Q that will be high enough to encode the
// content at the given rate.
for (q = rc->best_quality; q < rc->worst_quality; ++q) {
const double factor =
calc_correction_factor(err_per_mb, ERR_DIVISOR,
is_svc_upper_layer ? 0.8 : 0.5,
is_svc_upper_layer ? 1.0 : 0.90, q);
const int bits_per_mb = vp9_rc_bits_per_mb(INTER_FRAME, q,
factor * speed_term);
if (bits_per_mb <= target_norm_bits_per_mb)
break;
}
// Restriction on active max q for constrained quality mode.
if (cpi->oxcf.rc_mode == RC_MODE_CONSTRAINED_QUALITY)
q = MAX(q, oxcf->cq_level);
return q;
}
}
extern void vp9_new_framerate(VP9_COMP *cpi, double framerate);
void vp9_init_second_pass(VP9_COMP *cpi) {
SVC *const svc = &cpi->svc;
const VP9EncoderConfig *const oxcf = &cpi->oxcf;
const int is_spatial_svc = (svc->number_spatial_layers > 1) &&
(svc->number_temporal_layers == 1);
struct twopass_rc *const twopass = is_spatial_svc ?
&svc->layer_context[svc->spatial_layer_id].twopass : &cpi->twopass;
double frame_rate;
FIRSTPASS_STATS *stats;
zero_stats(&twopass->total_stats);
zero_stats(&twopass->total_left_stats);
if (!twopass->stats_in_end)
return;
stats = &twopass->total_stats;
*stats = *twopass->stats_in_end;
twopass->total_left_stats = *stats;
frame_rate = 10000000.0 * stats->count / stats->duration;
// Each frame can have a different duration, as the frame rate in the source
// isn't guaranteed to be constant. The frame rate prior to the first frame
// encoded in the second pass is a guess. However, the sum duration is not.
// It is calculated based on the actual durations of all frames from the
// first pass.
if (is_spatial_svc) {
vp9_update_spatial_layer_framerate(cpi, frame_rate);
twopass->bits_left = (int64_t)(stats->duration *
svc->layer_context[svc->spatial_layer_id].target_bandwidth /
10000000.0);
} else {
vp9_new_framerate(cpi, frame_rate);
twopass->bits_left = (int64_t)(stats->duration * oxcf->target_bandwidth /
10000000.0);
}
// Calculate a minimum intra value to be used in determining the IIratio
// scores used in the second pass. We have this minimum to make sure
// that clips that are static but "low complexity" in the intra domain
// are still boosted appropriately for KF/GF/ARF.
if (!is_spatial_svc) {
// We don't know the number of MBs for each layer at this point.
// So we will do it later.
twopass->kf_intra_err_min = KF_MB_INTRA_MIN * cpi->common.MBs;
twopass->gf_intra_err_min = GF_MB_INTRA_MIN * cpi->common.MBs;
}
// This variable monitors how far behind the second ref update is lagging.
twopass->sr_update_lag = 1;
// Scan the first pass file and calculate an average Intra / Inter error
// score ratio for the sequence.
{
const FIRSTPASS_STATS *const start_pos = twopass->stats_in;
FIRSTPASS_STATS this_frame;
double sum_iiratio = 0.0;
while (input_stats(twopass, &this_frame) != EOF) {
const double iiratio = this_frame.intra_error /
DOUBLE_DIVIDE_CHECK(this_frame.coded_error);
sum_iiratio += fclamp(iiratio, 1.0, 20.0);
}
twopass->avg_iiratio = sum_iiratio /
DOUBLE_DIVIDE_CHECK((double)stats->count);
reset_fpf_position(twopass, start_pos);
}
// Scan the first pass file and calculate a modified total error based upon
// the bias/power function used to allocate bits.
{
const FIRSTPASS_STATS *const start_pos = twopass->stats_in;
FIRSTPASS_STATS this_frame;
const double av_error = stats->ssim_weighted_pred_err /
DOUBLE_DIVIDE_CHECK(stats->count);
twopass->modified_error_total = 0.0;
twopass->modified_error_min =
(av_error * oxcf->two_pass_vbrmin_section) / 100;
twopass->modified_error_max =
(av_error * oxcf->two_pass_vbrmax_section) / 100;
while (input_stats(twopass, &this_frame) != EOF) {
twopass->modified_error_total +=
calculate_modified_err(cpi, &this_frame);
}
twopass->modified_error_left = twopass->modified_error_total;
reset_fpf_position(twopass, start_pos);
}
// Reset the vbr bits off target counter
cpi->rc.vbr_bits_off_target = 0;
}
// This function gives an estimate of how badly we believe the prediction
// quality is decaying from frame to frame.
static double get_prediction_decay_rate(const VP9_COMMON *cm,
const FIRSTPASS_STATS *next_frame) {
// Look at the observed drop in prediction quality between the last frame
// and the GF buffer (which contains an older frame).
const double mb_sr_err_diff = (next_frame->sr_coded_error -
next_frame->coded_error) / cm->MBs;
const double second_ref_decay = mb_sr_err_diff <= 512.0
? fclamp(pow(1.0 - (mb_sr_err_diff / 512.0), 0.5), 0.85, 1.0)
: 0.85;
return MIN(second_ref_decay, next_frame->pcnt_inter);
}
// Function to test for a condition where a complex transition is followed
// by a static section. For example in slide shows where there is a fade
// between slides. This is to help with more optimal kf and gf positioning.
static int detect_transition_to_still(struct twopass_rc *twopass,
int frame_interval, int still_interval,
double loop_decay_rate,
double last_decay_rate) {
int trans_to_still = 0;
// Break clause to detect very still sections after motion
// For example a static image after a fade or other transition
// instead of a clean scene cut.
if (frame_interval > MIN_GF_INTERVAL &&
loop_decay_rate >= 0.999 &&
last_decay_rate < 0.9) {
int j;
const FIRSTPASS_STATS *position = twopass->stats_in;
FIRSTPASS_STATS tmp_next_frame;
// Look ahead a few frames to see if static condition persists...
for (j = 0; j < still_interval; ++j) {
if (EOF == input_stats(twopass, &tmp_next_frame))
break;
if (tmp_next_frame.pcnt_inter - tmp_next_frame.pcnt_motion < 0.999)
break;
}
reset_fpf_position(twopass, position);
// Only if it does do we signal a transition to still.
if (j == still_interval)
trans_to_still = 1;
}
return trans_to_still;
}
// This function detects a flash through the high relative pcnt_second_ref
// score in the frame following a flash frame. The offset passed in should
// reflect this.
static int detect_flash(const struct twopass_rc *twopass, int offset) {
FIRSTPASS_STATS next_frame;
int flash_detected = 0;
// Read the frame data.
// The return is FALSE (no flash detected) if not a valid frame
if (read_frame_stats(twopass, &next_frame, offset) != EOF) {
// What we are looking for here is a situation where there is a
// brief break in prediction (such as a flash) but subsequent frames
// are reasonably well predicted by an earlier (pre flash) frame.
// The recovery after a flash is indicated by a high pcnt_second_ref
// compared to pcnt_inter.
if (next_frame.pcnt_second_ref > next_frame.pcnt_inter &&
next_frame.pcnt_second_ref >= 0.5)
flash_detected = 1;
}
return flash_detected;
}
// Update the motion related elements to the GF arf boost calculation.
static void accumulate_frame_motion_stats(
FIRSTPASS_STATS *this_frame,
double *this_frame_mv_in_out,
double *mv_in_out_accumulator,
double *abs_mv_in_out_accumulator,
double *mv_ratio_accumulator) {
double motion_pct;
// Accumulate motion stats.
motion_pct = this_frame->pcnt_motion;
// Accumulate Motion In/Out of frame stats.
*this_frame_mv_in_out = this_frame->mv_in_out_count * motion_pct;
*mv_in_out_accumulator += this_frame->mv_in_out_count * motion_pct;
*abs_mv_in_out_accumulator += fabs(this_frame->mv_in_out_count * motion_pct);
// Accumulate a measure of how uniform (or conversely how random)
// the motion field is (a ratio of absmv / mv).
if (motion_pct > 0.05) {
const double this_frame_mvr_ratio = fabs(this_frame->mvr_abs) /
DOUBLE_DIVIDE_CHECK(fabs(this_frame->MVr));
const double this_frame_mvc_ratio = fabs(this_frame->mvc_abs) /
DOUBLE_DIVIDE_CHECK(fabs(this_frame->MVc));
*mv_ratio_accumulator += (this_frame_mvr_ratio < this_frame->mvr_abs)
? (this_frame_mvr_ratio * motion_pct)
: this_frame->mvr_abs * motion_pct;
*mv_ratio_accumulator += (this_frame_mvc_ratio < this_frame->mvc_abs)
? (this_frame_mvc_ratio * motion_pct)
: this_frame->mvc_abs * motion_pct;
}
}
// Calculate a baseline boost number for the current frame.
static double calc_frame_boost(VP9_COMP *cpi, FIRSTPASS_STATS *this_frame,
double this_frame_mv_in_out) {
double frame_boost;
// Underlying boost factor is based on inter intra error ratio.
if (this_frame->intra_error > cpi->twopass.gf_intra_err_min)
frame_boost = (IIFACTOR * this_frame->intra_error /
DOUBLE_DIVIDE_CHECK(this_frame->coded_error));
else
frame_boost = (IIFACTOR * cpi->twopass.gf_intra_err_min /
DOUBLE_DIVIDE_CHECK(this_frame->coded_error));
// Increase boost for frames where new data coming into frame (e.g. zoom out).
// Slightly reduce boost if there is a net balance of motion out of the frame
// (zoom in). The range for this_frame_mv_in_out is -1.0 to +1.0.
if (this_frame_mv_in_out > 0.0)
frame_boost += frame_boost * (this_frame_mv_in_out * 2.0);
// In the extreme case the boost is halved.
else
frame_boost += frame_boost * (this_frame_mv_in_out / 2.0);
return MIN(frame_boost, GF_RMAX);
}
static int calc_arf_boost(VP9_COMP *cpi, int offset,
int f_frames, int b_frames,
int *f_boost, int *b_boost) {
FIRSTPASS_STATS this_frame;
struct twopass_rc *const twopass = &cpi->twopass;
int i;
double boost_score = 0.0;
double mv_ratio_accumulator = 0.0;
double decay_accumulator = 1.0;
double this_frame_mv_in_out = 0.0;
double mv_in_out_accumulator = 0.0;
double abs_mv_in_out_accumulator = 0.0;
int arf_boost;
int flash_detected = 0;
// Search forward from the proposed arf/next gf position.
for (i = 0; i < f_frames; ++i) {
if (read_frame_stats(twopass, &this_frame, (i + offset)) == EOF)
break;
// Update the motion related elements to the boost calculation.
accumulate_frame_motion_stats(&this_frame,
&this_frame_mv_in_out, &mv_in_out_accumulator,
&abs_mv_in_out_accumulator,
&mv_ratio_accumulator);
// We want to discount the flash frame itself and the recovery
// frame that follows as both will have poor scores.
flash_detected = detect_flash(twopass, i + offset) ||
detect_flash(twopass, i + offset + 1);
// Accumulate the effect of prediction quality decay.
if (!flash_detected) {
decay_accumulator *= get_prediction_decay_rate(&cpi->common, &this_frame);
decay_accumulator = decay_accumulator < MIN_DECAY_FACTOR
? MIN_DECAY_FACTOR : decay_accumulator;
}
boost_score += (decay_accumulator *
calc_frame_boost(cpi, &this_frame, this_frame_mv_in_out));
}
*f_boost = (int)boost_score;
// Reset for backward looking loop.
boost_score = 0.0;
mv_ratio_accumulator = 0.0;
decay_accumulator = 1.0;
this_frame_mv_in_out = 0.0;
mv_in_out_accumulator = 0.0;
abs_mv_in_out_accumulator = 0.0;
// Search backward towards last gf position.
for (i = -1; i >= -b_frames; --i) {
if (read_frame_stats(twopass, &this_frame, (i + offset)) == EOF)
break;
// Update the motion related elements to the boost calculation.
accumulate_frame_motion_stats(&this_frame,
&this_frame_mv_in_out, &mv_in_out_accumulator,
&abs_mv_in_out_accumulator,
&mv_ratio_accumulator);
// We want to discount the the flash frame itself and the recovery
// frame that follows as both will have poor scores.
flash_detected = detect_flash(twopass, i + offset) ||
detect_flash(twopass, i + offset + 1);
// Cumulative effect of prediction quality decay.
if (!flash_detected) {
decay_accumulator *= get_prediction_decay_rate(&cpi->common, &this_frame);
decay_accumulator = decay_accumulator < MIN_DECAY_FACTOR
? MIN_DECAY_FACTOR : decay_accumulator;
}
boost_score += (decay_accumulator *
calc_frame_boost(cpi, &this_frame, this_frame_mv_in_out));
}
*b_boost = (int)boost_score;
arf_boost = (*f_boost + *b_boost);
if (arf_boost < ((b_frames + f_frames) * 20))
arf_boost = ((b_frames + f_frames) * 20);
return arf_boost;
}
#if CONFIG_MULTIPLE_ARF
// Work out the frame coding order for a GF or an ARF group.
// The current implementation codes frames in their natural order for a
// GF group, and inserts additional ARFs into an ARF group using a
// binary split approach.
// NOTE: this function is currently implemented recursively.
static void schedule_frames(VP9_COMP *cpi, const int start, const int end,
const int arf_idx, const int gf_or_arf_group,
const int level) {
int i, abs_end, half_range;
int *cfo = cpi->frame_coding_order;
int idx = cpi->new_frame_coding_order_period;
// If (end < 0) an ARF should be coded at position (-end).
assert(start >= 0);
// printf("start:%d end:%d\n", start, end);
// GF Group: code frames in logical order.
if (gf_or_arf_group == 0) {
assert(end >= start);
for (i = start; i <= end; ++i) {
cfo[idx] = i;
cpi->arf_buffer_idx[idx] = arf_idx;
cpi->arf_weight[idx] = -1;
++idx;
}
cpi->new_frame_coding_order_period = idx;
return;
}
// ARF Group: Work out the ARF schedule and mark ARF frames as negative.
if (end < 0) {
// printf("start:%d end:%d\n", -end, -end);
// ARF frame is at the end of the range.
cfo[idx] = end;
// What ARF buffer does this ARF use as predictor.
cpi->arf_buffer_idx[idx] = (arf_idx > 2) ? (arf_idx - 1) : 2;
cpi->arf_weight[idx] = level;
++idx;
abs_end = -end;
} else {
abs_end = end;
}
half_range = (abs_end - start) >> 1;
// ARFs may not be adjacent, they must be separated by at least
// MIN_GF_INTERVAL non-ARF frames.
if ((start + MIN_GF_INTERVAL) >= (abs_end - MIN_GF_INTERVAL)) {
// printf("start:%d end:%d\n", start, abs_end);
// Update the coding order and active ARF.
for (i = start; i <= abs_end; ++i) {
cfo[idx] = i;
cpi->arf_buffer_idx[idx] = arf_idx;
cpi->arf_weight[idx] = -1;
++idx;
}
cpi->new_frame_coding_order_period = idx;
} else {
// Place a new ARF at the mid-point of the range.
cpi->new_frame_coding_order_period = idx;
schedule_frames(cpi, start, -(start + half_range), arf_idx + 1,
gf_or_arf_group, level + 1);
schedule_frames(cpi, start + half_range + 1, abs_end, arf_idx,
gf_or_arf_group, level + 1);
}
}
#define FIXED_ARF_GROUP_SIZE 16
void define_fixed_arf_period(VP9_COMP *cpi) {
int i;
int max_level = INT_MIN;
assert(cpi->multi_arf_enabled);
assert(cpi->oxcf.lag_in_frames >= FIXED_ARF_GROUP_SIZE);
// Save the weight of the last frame in the sequence before next
// sequence pattern overwrites it.
cpi->this_frame_weight = cpi->arf_weight[cpi->sequence_number];
assert(cpi->this_frame_weight >= 0);
cpi->twopass.gf_zeromotion_pct = 0;
// Initialize frame coding order variables.
cpi->new_frame_coding_order_period = 0;
cpi->next_frame_in_order = 0;
cpi->arf_buffered = 0;
vp9_zero(cpi->frame_coding_order);
vp9_zero(cpi->arf_buffer_idx);
vpx_memset(cpi->arf_weight, -1, sizeof(cpi->arf_weight));
if (cpi->rc.frames_to_key <= (FIXED_ARF_GROUP_SIZE + 8)) {
// Setup a GF group close to the keyframe.
cpi->rc.source_alt_ref_pending = 0;
cpi->rc.baseline_gf_interval = cpi->rc.frames_to_key;
schedule_frames(cpi, 0, (cpi->rc.baseline_gf_interval - 1), 2, 0, 0);
} else {
// Setup a fixed period ARF group.
cpi->rc.source_alt_ref_pending = 1;
cpi->rc.baseline_gf_interval = FIXED_ARF_GROUP_SIZE;
schedule_frames(cpi, 0, -(cpi->rc.baseline_gf_interval - 1), 2, 1, 0);
}
// Replace level indicator of -1 with correct level.
for (i = 0; i < cpi->new_frame_coding_order_period; ++i) {
if (cpi->arf_weight[i] > max_level) {
max_level = cpi->arf_weight[i];
}
}
++max_level;
for (i = 0; i < cpi->new_frame_coding_order_period; ++i) {
if (cpi->arf_weight[i] == -1) {
cpi->arf_weight[i] = max_level;
}
}
cpi->max_arf_level = max_level;
#if 0
printf("\nSchedule: ");
for (i = 0; i < cpi->new_frame_coding_order_period; ++i) {
printf("%4d ", cpi->frame_coding_order[i]);
}
printf("\n");
printf("ARFref: ");
for (i = 0; i < cpi->new_frame_coding_order_period; ++i) {
printf("%4d ", cpi->arf_buffer_idx[i]);
}
printf("\n");
printf("Weight: ");
for (i = 0; i < cpi->new_frame_coding_order_period; ++i) {
printf("%4d ", cpi->arf_weight[i]);
}
printf("\n");
#endif
}
#endif
// Analyse and define a gf/arf group.
static void define_gf_group(VP9_COMP *cpi, FIRSTPASS_STATS *this_frame) {
RATE_CONTROL *const rc = &cpi->rc;
const VP9EncoderConfig *const oxcf = &cpi->oxcf;
struct twopass_rc *const twopass = &cpi->twopass;
FIRSTPASS_STATS next_frame = { 0 };
const FIRSTPASS_STATS *start_pos;
int i;
double boost_score = 0.0;
double old_boost_score = 0.0;
double gf_group_err = 0.0;
double gf_first_frame_err = 0.0;
double mod_frame_err = 0.0;
double mv_ratio_accumulator = 0.0;
double decay_accumulator = 1.0;
double zero_motion_accumulator = 1.0;
double loop_decay_rate = 1.00;
double last_loop_decay_rate = 1.00;
double this_frame_mv_in_out = 0.0;
double mv_in_out_accumulator = 0.0;
double abs_mv_in_out_accumulator = 0.0;
double mv_ratio_accumulator_thresh;
// Max bits for a single frame.
const int max_bits = frame_max_bits(rc, oxcf);
unsigned int allow_alt_ref = oxcf->play_alternate && oxcf->lag_in_frames;
int f_boost = 0;
int b_boost = 0;
int flash_detected;
int active_max_gf_interval;
twopass->gf_group_bits = 0;
vp9_clear_system_state();
start_pos = twopass->stats_in;
// Load stats for the current frame.
mod_frame_err = calculate_modified_err(cpi, this_frame);
// Note the error of the frame at the start of the group. This will be
// the GF frame error if we code a normal gf.
gf_first_frame_err = mod_frame_err;
// If this is a key frame or the overlay from a previous arf then
// the error score / cost of this frame has already been accounted for.
if (cpi->common.frame_type == KEY_FRAME || rc->source_alt_ref_active)
gf_group_err -= gf_first_frame_err;
// Motion breakout threshold for loop below depends on image size.
mv_ratio_accumulator_thresh = (cpi->common.width + cpi->common.height) / 10.0;
// Work out a maximum interval for the GF.
// If the image appears completely static we can extend beyond this.
// The value chosen depends on the active Q range. At low Q we have
// bits to spare and are better with a smaller interval and smaller boost.
// At high Q when there are few bits to spare we are better with a longer
// interval to spread the cost of the GF.
//
active_max_gf_interval =
12 + ((int)vp9_convert_qindex_to_q(rc->last_q[INTER_FRAME]) >> 5);
if (active_max_gf_interval > rc->max_gf_interval)
active_max_gf_interval = rc->max_gf_interval;
i = 0;
while (i < rc->static_scene_max_gf_interval && i < rc->frames_to_key) {
++i;
// Accumulate error score of frames in this gf group.
mod_frame_err = calculate_modified_err(cpi, this_frame);
gf_group_err += mod_frame_err;
if (EOF == input_stats(twopass, &next_frame))
break;
// Test for the case where there is a brief flash but the prediction
// quality back to an earlier frame is then restored.
flash_detected = detect_flash(twopass, 0);
// Update the motion related elements to the boost calculation.
accumulate_frame_motion_stats(&next_frame,
&this_frame_mv_in_out, &mv_in_out_accumulator,
&abs_mv_in_out_accumulator,
&mv_ratio_accumulator);
// Accumulate the effect of prediction quality decay.
if (!flash_detected) {
last_loop_decay_rate = loop_decay_rate;
loop_decay_rate = get_prediction_decay_rate(&cpi->common, &next_frame);
decay_accumulator = decay_accumulator * loop_decay_rate;
// Monitor for static sections.
if ((next_frame.pcnt_inter - next_frame.pcnt_motion) <
zero_motion_accumulator) {
zero_motion_accumulator = next_frame.pcnt_inter -
next_frame.pcnt_motion;
}
// Break clause to detect very still sections after motion. For example,
// a static image after a fade or other transition.
if (detect_transition_to_still(twopass, i, 5, loop_decay_rate,
last_loop_decay_rate)) {
allow_alt_ref = 0;
break;
}
}
// Calculate a boost number for this frame.
boost_score += (decay_accumulator *
calc_frame_boost(cpi, &next_frame, this_frame_mv_in_out));
// Break out conditions.
if (
// Break at cpi->max_gf_interval unless almost totally static.
(i >= active_max_gf_interval && (zero_motion_accumulator < 0.995)) ||
(
// Don't break out with a very short interval.
(i > MIN_GF_INTERVAL) &&
((boost_score > 125.0) || (next_frame.pcnt_inter < 0.75)) &&
(!flash_detected) &&
((mv_ratio_accumulator > mv_ratio_accumulator_thresh) ||
(abs_mv_in_out_accumulator > 3.0) ||
(mv_in_out_accumulator < -2.0) ||
((boost_score - old_boost_score) < IIFACTOR)))) {
boost_score = old_boost_score;
break;
}
*this_frame = next_frame;
old_boost_score = boost_score;
}
twopass->gf_zeromotion_pct = (int)(zero_motion_accumulator * 1000.0);
// Don't allow a gf too near the next kf.
if ((rc->frames_to_key - i) < MIN_GF_INTERVAL) {
while (i < (rc->frames_to_key + !rc->next_key_frame_forced)) {
++i;
if (EOF == input_stats(twopass, this_frame))
break;
if (i < rc->frames_to_key) {
mod_frame_err = calculate_modified_err(cpi, this_frame);
gf_group_err += mod_frame_err;
}
}
}
#if CONFIG_MULTIPLE_ARF
if (cpi->multi_arf_enabled) {
// Initialize frame coding order variables.
cpi->new_frame_coding_order_period = 0;
cpi->next_frame_in_order = 0;
cpi->arf_buffered = 0;
vp9_zero(cpi->frame_coding_order);
vp9_zero(cpi->arf_buffer_idx);
vpx_memset(cpi->arf_weight, -1, sizeof(cpi->arf_weight));
}
#endif
// Set the interval until the next gf.
if (cpi->common.frame_type == KEY_FRAME || rc->source_alt_ref_active)
rc->baseline_gf_interval = i - 1;
else
rc->baseline_gf_interval = i;
// Should we use the alternate reference frame.
if (allow_alt_ref &&
(i < cpi->oxcf.lag_in_frames) &&
(i >= MIN_GF_INTERVAL) &&
// For real scene cuts (not forced kfs) don't allow arf very near kf.
(rc->next_key_frame_forced ||
(i <= (rc->frames_to_key - MIN_GF_INTERVAL)))) {
// Calculate the boost for alt ref.
rc->gfu_boost = calc_arf_boost(cpi, 0, (i - 1), (i - 1), &f_boost,
&b_boost);
rc->source_alt_ref_pending = 1;
#if CONFIG_MULTIPLE_ARF
// Set the ARF schedule.
if (cpi->multi_arf_enabled) {
schedule_frames(cpi, 0, -(rc->baseline_gf_interval - 1), 2, 1, 0);
}
#endif
} else {
rc->gfu_boost = (int)boost_score;
rc->source_alt_ref_pending = 0;
#if CONFIG_MULTIPLE_ARF
// Set the GF schedule.
if (cpi->multi_arf_enabled) {
schedule_frames(cpi, 0, rc->baseline_gf_interval - 1, 2, 0, 0);
assert(cpi->new_frame_coding_order_period ==
rc->baseline_gf_interval);
}
#endif
}
#if CONFIG_MULTIPLE_ARF
if (cpi->multi_arf_enabled && (cpi->common.frame_type != KEY_FRAME)) {
int max_level = INT_MIN;
// Replace level indicator of -1 with correct level.
for (i = 0; i < cpi->frame_coding_order_period; ++i) {
if (cpi->arf_weight[i] > max_level) {
max_level = cpi->arf_weight[i];
}
}
++max_level;
for (i = 0; i < cpi->frame_coding_order_period; ++i) {
if (cpi->arf_weight[i] == -1) {
cpi->arf_weight[i] = max_level;
}
}
cpi->max_arf_level = max_level;
}
#if 0
if (cpi->multi_arf_enabled) {
printf("\nSchedule: ");
for (i = 0; i < cpi->new_frame_coding_order_period; ++i) {
printf("%4d ", cpi->frame_coding_order[i]);
}
printf("\n");
printf("ARFref: ");
for (i = 0; i < cpi->new_frame_coding_order_period; ++i) {
printf("%4d ", cpi->arf_buffer_idx[i]);
}
printf("\n");
printf("Weight: ");
for (i = 0; i < cpi->new_frame_coding_order_period; ++i) {
printf("%4d ", cpi->arf_weight[i]);
}
printf("\n");
}
#endif
#endif
// Calculate the bits to be allocated to the group as a whole.
if (twopass->kf_group_bits > 0 && twopass->kf_group_error_left > 0) {
twopass->gf_group_bits = (int64_t)(twopass->kf_group_bits *
(gf_group_err / twopass->kf_group_error_left));
} else {
twopass->gf_group_bits = 0;
}
twopass->gf_group_bits = (twopass->gf_group_bits < 0) ?
0 : (twopass->gf_group_bits > twopass->kf_group_bits) ?
twopass->kf_group_bits : twopass->gf_group_bits;
// Clip cpi->twopass.gf_group_bits based on user supplied data rate
// variability limit, cpi->oxcf.two_pass_vbrmax_section.
if (twopass->gf_group_bits > (int64_t)max_bits * rc->baseline_gf_interval)
twopass->gf_group_bits = (int64_t)max_bits * rc->baseline_gf_interval;
// Reset the file position.
reset_fpf_position(twopass, start_pos);
// Assign bits to the arf or gf.
for (i = 0; i <= (rc->source_alt_ref_pending &&
cpi->common.frame_type != KEY_FRAME); ++i) {
int allocation_chunks;
int q = rc->last_q[INTER_FRAME];
int gf_bits;
int boost = (rc->gfu_boost * gfboost_qadjust(q)) / 100;
// Set max and minimum boost and hence minimum allocation.
boost = clamp(boost, 125, (rc->baseline_gf_interval + 1) * 200);
if (rc->source_alt_ref_pending && i == 0)
allocation_chunks = ((rc->baseline_gf_interval + 1) * 100) + boost;
else
allocation_chunks = (rc->baseline_gf_interval * 100) + (boost - 100);
// Prevent overflow.
if (boost > 1023) {
int divisor = boost >> 10;
boost /= divisor;
allocation_chunks /= divisor;
}
// Calculate the number of bits to be spent on the gf or arf based on
// the boost number.
gf_bits = (int)((double)boost * (twopass->gf_group_bits /
(double)allocation_chunks));
// If the frame that is to be boosted is simpler than the average for
// the gf/arf group then use an alternative calculation
// based on the error score of the frame itself.
if (rc->baseline_gf_interval < 1 ||
mod_frame_err < gf_group_err / (double)rc->baseline_gf_interval) {
double alt_gf_grp_bits = (double)twopass->kf_group_bits *
(mod_frame_err * (double)rc->baseline_gf_interval) /
DOUBLE_DIVIDE_CHECK(twopass->kf_group_error_left);
int alt_gf_bits = (int)((double)boost * (alt_gf_grp_bits /
(double)allocation_chunks));
if (gf_bits > alt_gf_bits)
gf_bits = alt_gf_bits;
} else {
// If it is harder than other frames in the group make sure it at
// least receives an allocation in keeping with its relative error
// score, otherwise it may be worse off than an "un-boosted" frame.
int alt_gf_bits = (int)((double)twopass->kf_group_bits *
mod_frame_err /
DOUBLE_DIVIDE_CHECK(twopass->kf_group_error_left));
if (alt_gf_bits > gf_bits)
gf_bits = alt_gf_bits;
}
// Don't allow a negative value for gf_bits.
if (gf_bits < 0)
gf_bits = 0;
if (i == 0) {
twopass->gf_bits = gf_bits;
}
if (i == 1 ||
(!rc->source_alt_ref_pending && cpi->common.frame_type != KEY_FRAME &&
!vp9_is_upper_layer_key_frame(cpi))) {
// Calculate the per frame bit target for this frame.
vp9_rc_set_frame_target(cpi, gf_bits);
}
}
{
// Adjust KF group bits and error remaining.
twopass->kf_group_error_left -= (int64_t)gf_group_err;
// If this is an arf update we want to remove the score for the overlay
// frame at the end which will usually be very cheap to code.
// The overlay frame has already, in effect, been coded so we want to spread
// the remaining bits among the other frames.
// For normal GFs remove the score for the GF itself unless this is
// also a key frame in which case it has already been accounted for.
if (rc->source_alt_ref_pending) {
twopass->gf_group_error_left = (int64_t)(gf_group_err - mod_frame_err);
} else if (cpi->common.frame_type != KEY_FRAME) {
twopass->gf_group_error_left = (int64_t)(gf_group_err
- gf_first_frame_err);
} else {
twopass->gf_group_error_left = (int64_t)gf_group_err;
}
// This condition could fail if there are two kfs very close together
// despite MIN_GF_INTERVAL and would cause a divide by 0 in the
// calculation of alt_extra_bits.
if (rc->baseline_gf_interval >= 3) {
const int boost = rc->source_alt_ref_pending ? b_boost : rc->gfu_boost;
if (boost >= 150) {
const int pct_extra = MIN(20, (boost - 100) / 50);
const int alt_extra_bits = (int)((
MAX(twopass->gf_group_bits - twopass->gf_bits, 0) *
pct_extra) / 100);
twopass->gf_group_bits -= alt_extra_bits;
}
}
}
if (cpi->common.frame_type != KEY_FRAME) {
FIRSTPASS_STATS sectionstats;
zero_stats(§ionstats);
reset_fpf_position(twopass, start_pos);
for (i = 0; i < rc->baseline_gf_interval; ++i) {
input_stats(twopass, &next_frame);
accumulate_stats(§ionstats, &next_frame);
}
avg_stats(§ionstats);
twopass->section_intra_rating = (int)
(sectionstats.intra_error /
DOUBLE_DIVIDE_CHECK(sectionstats.coded_error));
reset_fpf_position(twopass, start_pos);
}
}
// Allocate bits to a normal frame that is neither a gf an arf or a key frame.
static void assign_std_frame_bits(VP9_COMP *cpi, FIRSTPASS_STATS *this_frame) {
struct twopass_rc *twopass = &cpi->twopass;
// For a single frame.
const int max_bits = frame_max_bits(&cpi->rc, &cpi->oxcf);
// Calculate modified prediction error used in bit allocation.
const double modified_err = calculate_modified_err(cpi, this_frame);
int target_frame_size;
double err_fraction;
if (twopass->gf_group_error_left > 0)
// What portion of the remaining GF group error is used by this frame.
err_fraction = modified_err / twopass->gf_group_error_left;
else
err_fraction = 0.0;
// How many of those bits available for allocation should we give it?
target_frame_size = (int)((double)twopass->gf_group_bits * err_fraction);
// Clip target size to 0 - max_bits (or cpi->twopass.gf_group_bits) at
// the top end.
target_frame_size = clamp(target_frame_size, 0,
MIN(max_bits, (int)twopass->gf_group_bits));
// Adjust error and bits remaining.
twopass->gf_group_error_left -= (int64_t)modified_err;
// Per frame bit target for this frame.
vp9_rc_set_frame_target(cpi, target_frame_size);
}
static int test_candidate_kf(struct twopass_rc *twopass,
const FIRSTPASS_STATS *last_frame,
const FIRSTPASS_STATS *this_frame,
const FIRSTPASS_STATS *next_frame) {
int is_viable_kf = 0;
// Does the frame satisfy the primary criteria of a key frame?
// If so, then examine how well it predicts subsequent frames.
if ((this_frame->pcnt_second_ref < 0.10) &&
(next_frame->pcnt_second_ref < 0.10) &&
((this_frame->pcnt_inter < 0.05) ||
(((this_frame->pcnt_inter - this_frame->pcnt_neutral) < 0.35) &&
((this_frame->intra_error /
DOUBLE_DIVIDE_CHECK(this_frame->coded_error)) < 2.5) &&
((fabs(last_frame->coded_error - this_frame->coded_error) /
DOUBLE_DIVIDE_CHECK(this_frame->coded_error) > 0.40) ||
(fabs(last_frame->intra_error - this_frame->intra_error) /
DOUBLE_DIVIDE_CHECK(this_frame->intra_error) > 0.40) ||
((next_frame->intra_error /
DOUBLE_DIVIDE_CHECK(next_frame->coded_error)) > 3.5))))) {
int i;
const FIRSTPASS_STATS *start_pos = twopass->stats_in;
FIRSTPASS_STATS local_next_frame = *next_frame;
double boost_score = 0.0;
double old_boost_score = 0.0;
double decay_accumulator = 1.0;
// Examine how well the key frame predicts subsequent frames.
for (i = 0; i < 16; ++i) {
double next_iiratio = (IIKFACTOR1 * local_next_frame.intra_error /
DOUBLE_DIVIDE_CHECK(local_next_frame.coded_error));
if (next_iiratio > RMAX)
next_iiratio = RMAX;
// Cumulative effect of decay in prediction quality.
if (local_next_frame.pcnt_inter > 0.85)
decay_accumulator *= local_next_frame.pcnt_inter;
else
decay_accumulator *= (0.85 + local_next_frame.pcnt_inter) / 2.0;
// Keep a running total.
boost_score += (decay_accumulator * next_iiratio);
// Test various breakout clauses.
if ((local_next_frame.pcnt_inter < 0.05) ||
(next_iiratio < 1.5) ||
(((local_next_frame.pcnt_inter -
local_next_frame.pcnt_neutral) < 0.20) &&
(next_iiratio < 3.0)) ||
((boost_score - old_boost_score) < 3.0) ||
(local_next_frame.intra_error < 200)) {
break;
}
old_boost_score = boost_score;
// Get the next frame details
if (EOF == input_stats(twopass, &local_next_frame))
break;
}
// If there is tolerable prediction for at least the next 3 frames then
// break out else discard this potential key frame and move on
if (boost_score > 30.0 && (i > 3)) {
is_viable_kf = 1;
} else {
// Reset the file position
reset_fpf_position(twopass, start_pos);
is_viable_kf = 0;
}
}
return is_viable_kf;
}
static void find_next_key_frame(VP9_COMP *cpi, FIRSTPASS_STATS *this_frame) {
int i, j;
RATE_CONTROL *const rc = &cpi->rc;
struct twopass_rc *const twopass = &cpi->twopass;
const FIRSTPASS_STATS first_frame = *this_frame;
const FIRSTPASS_STATS *start_position = twopass->stats_in;
FIRSTPASS_STATS next_frame;
FIRSTPASS_STATS last_frame;
double decay_accumulator = 1.0;
double zero_motion_accumulator = 1.0;
double boost_score = 0.0;
double kf_mod_err = 0.0;
double kf_group_err = 0.0;
double recent_loop_decay[8] = {1.0, 1.0, 1.0, 1.0, 1.0, 1.0, 1.0, 1.0};
vp9_zero(next_frame);
cpi->common.frame_type = KEY_FRAME;
// Is this a forced key frame by interval.
rc->this_key_frame_forced = rc->next_key_frame_forced;
// Clear the alt ref active flag as this can never be active on a key frame.
rc->source_alt_ref_active = 0;
// KF is always a GF so clear frames till next gf counter.
rc->frames_till_gf_update_due = 0;
rc->frames_to_key = 1;
twopass->kf_group_bits = 0; // Total bits available to kf group
twopass->kf_group_error_left = 0; // Group modified error score.
kf_mod_err = calculate_modified_err(cpi, this_frame);
// Find the next keyframe.
i = 0;
while (twopass->stats_in < twopass->stats_in_end &&
rc->frames_to_key < cpi->oxcf.key_freq) {
// Accumulate kf group error.
kf_group_err += calculate_modified_err(cpi, this_frame);
// Load the next frame's stats.
last_frame = *this_frame;
input_stats(twopass, this_frame);
// Provided that we are not at the end of the file...
if (cpi->oxcf.auto_key &&
lookup_next_frame_stats(twopass, &next_frame) != EOF) {
double loop_decay_rate;
// Check for a scene cut.
if (test_candidate_kf(twopass, &last_frame, this_frame, &next_frame))
break;
// How fast is the prediction quality decaying?
loop_decay_rate = get_prediction_decay_rate(&cpi->common, &next_frame);
// We want to know something about the recent past... rather than
// as used elsewhere where we are concerned with decay in prediction
// quality since the last GF or KF.
recent_loop_decay[i % 8] = loop_decay_rate;
decay_accumulator = 1.0;
for (j = 0; j < 8; ++j)
decay_accumulator *= recent_loop_decay[j];
// Special check for transition or high motion followed by a
// static scene.
if (detect_transition_to_still(twopass, i, cpi->oxcf.key_freq - i,
loop_decay_rate, decay_accumulator))
break;
// Step on to the next frame.
++rc->frames_to_key;
// If we don't have a real key frame within the next two
// key_freq intervals then break out of the loop.
if (rc->frames_to_key >= 2 * cpi->oxcf.key_freq)
break;
} else {
++rc->frames_to_key;
}
++i;
}
// If there is a max kf interval set by the user we must obey it.
// We already breakout of the loop above at 2x max.
// This code centers the extra kf if the actual natural interval
// is between 1x and 2x.
if (cpi->oxcf.auto_key &&
rc->frames_to_key > cpi->oxcf.key_freq) {
FIRSTPASS_STATS tmp_frame = first_frame;
rc->frames_to_key /= 2;
// Reset to the start of the group.
reset_fpf_position(twopass, start_position);
kf_group_err = 0;
// Rescan to get the correct error data for the forced kf group.
for (i = 0; i < rc->frames_to_key; ++i) {
kf_group_err += calculate_modified_err(cpi, &tmp_frame);
input_stats(twopass, &tmp_frame);
}
rc->next_key_frame_forced = 1;
} else if (twopass->stats_in == twopass->stats_in_end ||
rc->frames_to_key >= cpi->oxcf.key_freq) {
rc->next_key_frame_forced = 1;
} else {
rc->next_key_frame_forced = 0;
}
// Special case for the last key frame of the file.
if (twopass->stats_in >= twopass->stats_in_end) {
// Accumulate kf group error.
kf_group_err += calculate_modified_err(cpi, this_frame);
}
// Calculate the number of bits that should be assigned to the kf group.
if (twopass->bits_left > 0 && twopass->modified_error_left > 0.0) {
// Maximum number of bits for a single normal frame (not key frame).
const int max_bits = frame_max_bits(rc, &cpi->oxcf);
// Maximum number of bits allocated to the key frame group.
int64_t max_grp_bits;
// Default allocation based on bits left and relative
// complexity of the section.
twopass->kf_group_bits = (int64_t)(twopass->bits_left *
(kf_group_err / twopass->modified_error_left));
// Clip based on maximum per frame rate defined by the user.
max_grp_bits = (int64_t)max_bits * (int64_t)rc->frames_to_key;
if (twopass->kf_group_bits > max_grp_bits)
twopass->kf_group_bits = max_grp_bits;
} else {
twopass->kf_group_bits = 0;
}
// Reset the first pass file position.
reset_fpf_position(twopass, start_position);
// Determine how big to make this keyframe based on how well the subsequent
// frames use inter blocks.
decay_accumulator = 1.0;
boost_score = 0.0;
// Scan through the kf group collating various stats.
for (i = 0; i < rc->frames_to_key; ++i) {
if (EOF == input_stats(twopass, &next_frame))
break;
// Monitor for static sections.
if ((next_frame.pcnt_inter - next_frame.pcnt_motion) <
zero_motion_accumulator) {
zero_motion_accumulator = (next_frame.pcnt_inter -
next_frame.pcnt_motion);
}
// For the first few frames collect data to decide kf boost.
if (i <= (rc->max_gf_interval * 2)) {
double r;
if (next_frame.intra_error > twopass->kf_intra_err_min)
r = (IIKFACTOR2 * next_frame.intra_error /
DOUBLE_DIVIDE_CHECK(next_frame.coded_error));
else
r = (IIKFACTOR2 * twopass->kf_intra_err_min /
DOUBLE_DIVIDE_CHECK(next_frame.coded_error));
if (r > RMAX)
r = RMAX;
// How fast is prediction quality decaying.
if (!detect_flash(twopass, 0)) {
const double loop_decay_rate = get_prediction_decay_rate(&cpi->common,
&next_frame);
decay_accumulator *= loop_decay_rate;
decay_accumulator = MAX(decay_accumulator, MIN_DECAY_FACTOR);
}
boost_score += (decay_accumulator * r);
}
}
{
FIRSTPASS_STATS sectionstats;
zero_stats(§ionstats);
reset_fpf_position(twopass, start_position);
for (i = 0; i < rc->frames_to_key; ++i) {
input_stats(twopass, &next_frame);
accumulate_stats(§ionstats, &next_frame);
}
avg_stats(§ionstats);
twopass->section_intra_rating = (int) (sectionstats.intra_error /
DOUBLE_DIVIDE_CHECK(sectionstats.coded_error));
}
// Reset the first pass file position.
reset_fpf_position(twopass, start_position);
// Work out how many bits to allocate for the key frame itself.
if (1) {
int kf_boost = (int)boost_score;
int allocation_chunks;
if (kf_boost < (rc->frames_to_key * 3))
kf_boost = (rc->frames_to_key * 3);
if (kf_boost < MIN_KF_BOOST)
kf_boost = MIN_KF_BOOST;
// Make a note of baseline boost and the zero motion
// accumulator value for use elsewhere.
rc->kf_boost = kf_boost;
twopass->kf_zeromotion_pct = (int)(zero_motion_accumulator * 100.0);
// Key frame size depends on:
// (1) the error score for the whole key frame group,
// (2) the key frames' own error if this is smaller than the
// average for the group (optional),
// (3) insuring that the frame receives at least the allocation it would
// have received based on its own error score vs the error score
// remaining.
// Special case:
// If the sequence appears almost totally static we want to spend almost
// all of the bits on the key frame.
//
// We use (cpi->rc.frames_to_key - 1) below because the key frame itself is
// taken care of by kf_boost.
if (zero_motion_accumulator >= 0.99) {
allocation_chunks = ((rc->frames_to_key - 1) * 10) + kf_boost;
} else {
allocation_chunks = ((rc->frames_to_key - 1) * 100) + kf_boost;
}
// Prevent overflow.
if (kf_boost > 1028) {
const int divisor = kf_boost >> 10;
kf_boost /= divisor;
allocation_chunks /= divisor;
}
twopass->kf_group_bits = MAX(0, twopass->kf_group_bits);
// Calculate the number of bits to be spent on the key frame.
twopass->kf_bits = (int)((double)kf_boost *
((double)twopass->kf_group_bits / allocation_chunks));
// If the key frame is actually easier than the average for the
// kf group (which does sometimes happen, e.g. a blank intro frame)
// then use an alternate calculation based on the kf error score
// which should give a smaller key frame.
if (kf_mod_err < kf_group_err / rc->frames_to_key) {
double alt_kf_grp_bits = ((double)twopass->bits_left *
(kf_mod_err * (double)rc->frames_to_key) /
DOUBLE_DIVIDE_CHECK(twopass->modified_error_left));
const int alt_kf_bits = (int)((double)kf_boost *
(alt_kf_grp_bits / (double)allocation_chunks));
if (twopass->kf_bits > alt_kf_bits)
twopass->kf_bits = alt_kf_bits;
} else {
// Else if it is much harder than other frames in the group make sure
// it at least receives an allocation in keeping with its relative
// error score.
const int alt_kf_bits = (int)((double)twopass->bits_left * (kf_mod_err /
DOUBLE_DIVIDE_CHECK(twopass->modified_error_left)));
if (alt_kf_bits > twopass->kf_bits)
twopass->kf_bits = alt_kf_bits;
}
twopass->kf_group_bits -= twopass->kf_bits;
// Per frame bit target for this frame.
vp9_rc_set_frame_target(cpi, twopass->kf_bits);
}
// Note the total error score of the kf group minus the key frame itself.
twopass->kf_group_error_left = (int)(kf_group_err - kf_mod_err);
// Adjust the count of total modified error left.
// The count of bits left is adjusted elsewhere based on real coded frame
// sizes.
twopass->modified_error_left -= kf_group_err;
}
void vp9_rc_get_first_pass_params(VP9_COMP *cpi) {
VP9_COMMON *const cm = &cpi->common;
if (!cpi->refresh_alt_ref_frame &&
(cm->current_video_frame == 0 ||
(cpi->frame_flags & FRAMEFLAGS_KEY))) {
cm->frame_type = KEY_FRAME;
} else {
cm->frame_type = INTER_FRAME;
}
// Do not use periodic key frames.
cpi->rc.frames_to_key = INT_MAX;
}
// For VBR...adjustment to the frame target based on error from previous frames
void vbr_rate_correction(int * this_frame_target,
const int64_t vbr_bits_off_target) {
int max_delta = (*this_frame_target * 15) / 100;
// vbr_bits_off_target > 0 means we have extra bits to spend
if (vbr_bits_off_target > 0) {
*this_frame_target +=
(vbr_bits_off_target > max_delta) ? max_delta
: (int)vbr_bits_off_target;
} else {
*this_frame_target -=
(vbr_bits_off_target < -max_delta) ? max_delta
: (int)-vbr_bits_off_target;
}
}
void vp9_rc_get_second_pass_params(VP9_COMP *cpi) {
VP9_COMMON *const cm = &cpi->common;
RATE_CONTROL *const rc = &cpi->rc;
struct twopass_rc *const twopass = &cpi->twopass;
int frames_left;
FIRSTPASS_STATS this_frame;
FIRSTPASS_STATS this_frame_copy;
double this_frame_intra_error;
double this_frame_coded_error;
int target;
LAYER_CONTEXT *lc = NULL;
int is_spatial_svc = (cpi->use_svc && cpi->svc.number_temporal_layers == 1);
if (is_spatial_svc) {
lc = &cpi->svc.layer_context[cpi->svc.spatial_layer_id];
frames_left = (int)(twopass->total_stats.count -
lc->current_video_frame_in_layer);
} else {
frames_left = (int)(twopass->total_stats.count -
cm->current_video_frame);
}
if (!twopass->stats_in)
return;
if (cpi->refresh_alt_ref_frame) {
int modified_target = twopass->gf_bits;
rc->base_frame_target = twopass->gf_bits;
cm->frame_type = INTER_FRAME;
#ifdef LONG_TERM_VBR_CORRECTION
// Correction to rate target based on prior over or under shoot.
if (cpi->oxcf.rc_mode == RC_MODE_VBR)
vbr_rate_correction(&modified_target, rc->vbr_bits_off_target);
#endif
vp9_rc_set_frame_target(cpi, modified_target);
return;
}
vp9_clear_system_state();
if (is_spatial_svc && twopass->kf_intra_err_min == 0) {
twopass->kf_intra_err_min = KF_MB_INTRA_MIN * cpi->common.MBs;
twopass->gf_intra_err_min = GF_MB_INTRA_MIN * cpi->common.MBs;
}
if (cpi->oxcf.rc_mode == RC_MODE_CONSTANT_QUALITY) {
twopass->active_worst_quality = cpi->oxcf.cq_level;
} else if (cm->current_video_frame == 0 ||
(is_spatial_svc && lc->current_video_frame_in_layer == 0)) {
// Special case code for first frame.
const int section_target_bandwidth = (int)(twopass->bits_left /
frames_left);
const int tmp_q = get_twopass_worst_quality(cpi, &twopass->total_left_stats,
section_target_bandwidth);
twopass->active_worst_quality = tmp_q;
rc->ni_av_qi = tmp_q;
rc->avg_q = vp9_convert_qindex_to_q(tmp_q);
}
vp9_zero(this_frame);
if (EOF == input_stats(twopass, &this_frame))
return;
this_frame_intra_error = this_frame.intra_error;
this_frame_coded_error = this_frame.coded_error;
// Keyframe and section processing.
if (rc->frames_to_key == 0 ||
(cpi->frame_flags & FRAMEFLAGS_KEY)) {
// Define next KF group and assign bits to it.
this_frame_copy = this_frame;
find_next_key_frame(cpi, &this_frame_copy);
// Don't place key frame in any enhancement layers in spatial svc
if (cpi->use_svc && cpi->svc.number_temporal_layers == 1) {
lc->is_key_frame = 1;
if (cpi->svc.spatial_layer_id > 0) {
cm->frame_type = INTER_FRAME;
}
}
} else {
if (cpi->use_svc && cpi->svc.number_temporal_layers == 1) {
lc->is_key_frame = 0;
}
cm->frame_type = INTER_FRAME;
}
// Is this frame a GF / ARF? (Note: a key frame is always also a GF).
if (rc->frames_till_gf_update_due == 0) {
// Define next gf group and assign bits to it.
this_frame_copy = this_frame;
#if CONFIG_MULTIPLE_ARF
if (cpi->multi_arf_enabled) {
define_fixed_arf_period(cpi);
} else {
#endif
define_gf_group(cpi, &this_frame_copy);
#if CONFIG_MULTIPLE_ARF
}
#endif
if (twopass->gf_zeromotion_pct > 995) {
// As long as max_thresh for encode breakout is small enough, it is ok
// to enable it for show frame, i.e. set allow_encode_breakout to
// ENCODE_BREAKOUT_LIMITED.
if (!cm->show_frame)
cpi->allow_encode_breakout = ENCODE_BREAKOUT_DISABLED;
else
cpi->allow_encode_breakout = ENCODE_BREAKOUT_LIMITED;
}
rc->frames_till_gf_update_due = rc->baseline_gf_interval;
cpi->refresh_golden_frame = 1;
} else {
// Otherwise this is an ordinary frame.
// Assign bits from those allocated to the GF group.
this_frame_copy = this_frame;
assign_std_frame_bits(cpi, &this_frame_copy);
}
// Keep a globally available copy of this and the next frame's iiratio.
twopass->this_iiratio = (int)(this_frame_intra_error /
DOUBLE_DIVIDE_CHECK(this_frame_coded_error));
{
FIRSTPASS_STATS next_frame;
if (lookup_next_frame_stats(twopass, &next_frame) != EOF) {
twopass->next_iiratio = (int)(next_frame.intra_error /
DOUBLE_DIVIDE_CHECK(next_frame.coded_error));
}
}
if (cpi->common.frame_type == KEY_FRAME)
target = vp9_rc_clamp_iframe_target_size(cpi, rc->this_frame_target);
else
target = vp9_rc_clamp_pframe_target_size(cpi, rc->this_frame_target);
rc->base_frame_target = target;
#ifdef LONG_TERM_VBR_CORRECTION
// Correction to rate target based on prior over or under shoot.
if (cpi->oxcf.rc_mode == RC_MODE_VBR)
vbr_rate_correction(&target, rc->vbr_bits_off_target);
#endif
vp9_rc_set_frame_target(cpi, target);
// Update the total stats remaining structure.
subtract_stats(&twopass->total_left_stats, &this_frame);
}
void vp9_twopass_postencode_update(VP9_COMP *cpi) {
RATE_CONTROL *const rc = &cpi->rc;
#ifdef LONG_TERM_VBR_CORRECTION
// In this experimental mode, the VBR correction is done exclusively through
// rc->vbr_bits_off_target. Based on the sign of this value, a limited %
// adjustment is made to the target rate of subsequent frames, to try and
// push it back towards 0. This mode is less likely to suffer from
// extreme behaviour at the end of a clip or group of frames.
const int bits_used = rc->base_frame_target;
rc->vbr_bits_off_target += rc->base_frame_target - rc->projected_frame_size;
#else
// In this mode, VBR correction is acheived by altering bits_left,
// kf_group_bits & gf_group_bits to reflect any deviation from the target
// rate in this frame. This alters the allocation of bits to the
// remaning frames in the group / clip.
//
// This method can give rise to unstable behaviour near the end of a clip
// or kf/gf group of frames where any accumulated error is corrected over an
// ever decreasing number of frames. Hence we change the balance of target
// vs. actual bitrate gradually as we progress towards the end of the
// sequence in order to mitigate this effect.
const double progress =
(double)(cpi->twopass.stats_in - cpi->twopass.stats_in_start) /
(cpi->twopass.stats_in_end - cpi->twopass.stats_in_start);
const int bits_used = progress * rc->this_frame_target +
(1.0 - progress) * rc->projected_frame_size;
#endif
cpi->twopass.bits_left -= bits_used;
cpi->twopass.bits_left = MAX(cpi->twopass.bits_left, 0);
#ifdef LONG_TERM_VBR_CORRECTION
if (cpi->common.frame_type != KEY_FRAME &&
!vp9_is_upper_layer_key_frame(cpi)) {
#else
if (cpi->common.frame_type == KEY_FRAME ||
vp9_is_upper_layer_key_frame(cpi)) {
// For key frames kf_group_bits already had the target bits subtracted out.
// So now update to the correct value based on the actual bits used.
cpi->twopass.kf_group_bits += cpi->rc.this_frame_target - bits_used;
} else {
#endif
cpi->twopass.kf_group_bits -= bits_used;
cpi->twopass.gf_group_bits -= bits_used;
cpi->twopass.gf_group_bits = MAX(cpi->twopass.gf_group_bits, 0);
}
cpi->twopass.kf_group_bits = MAX(cpi->twopass.kf_group_bits, 0);
}