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vpx/vp9/encoder/vp9_firstpass.c
Pengchong Jin cdc954fdc8 skip the un-necessary motion search in the first pass 
This patch allows the VP9 encoder to skip the un-necessary
motion search in the first pass. It computes the motion error
of 0,0 motion using the last source frame as the reference,
and skips the further motion search if this error is small.

Borg test shows overall the patch gives PSNR gain (derf -0.001%,
yt 0.341%, hd 0.282%). Individual clips may have PSNR gain or
loss. The best PSNR performance is 7.347% and the worst is -0.662%.
The first pass encoding speedup for slideshow clips is over 30%.

Change-Id: I4cac4dbd911f277ee858e161f3ca652c771344fe
2014-06-16 10:16:27 -07:00

2300 lines
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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 <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 SVC_FACTOR_PT_LOW 0.45
#define FACTOR_PT_LOW 0.5
#define FACTOR_PT_HIGH 0.9
#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(TWO_PASS *p,
const FIRSTPASS_STATS *position) {
p->stats_in = position;
}
static int lookup_next_frame_stats(const TWO_PASS *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 TWO_PASS *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(TWO_PASS *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 %12.4f %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->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->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->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->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->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 TWO_PASS *twopass,
const VP9EncoderConfig *oxcf,
const FIRSTPASS_STATS *this_frame) {
const FIRSTPASS_STATS *const stats = &twopass->total_stats;
const double av_err = stats->coded_error / stats->count;
const double modified_error = av_err *
pow(this_frame->coded_error / DOUBLE_DIVIDE_CHECK(av_err),
oxcf->two_pass_vbrbias / 100.0);
return fclamp(modified_error,
twopass->modified_error_min, twopass->modified_error_max);
}
// 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;
}
}
static int find_fp_qindex() {
int i;
for (i = 0; i < QINDEX_RANGE; ++i)
if (vp9_convert_qindex_to_q(i) >= 30.0)
break;
if (i == QINDEX_RANGE)
i--;
return i;
}
static void set_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;
}
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 = &cpi->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;
TWO_PASS *twopass = &cpi->twopass;
const MV zero_mv = {0, 0};
const YV12_BUFFER_CONFIG *first_ref_buf = lst_yv12;
vp9_clear_system_state();
set_first_pass_params(cpi);
vp9_set_quantizer(cm, find_fp_qindex());
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->plane, 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, raw_motion_error;
int_mv mv, tmp_mv;
struct buf_2d unscaled_last_source_buf_2d;
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;
// Compute the motion error of the 0,0 motion using the last source
// frame as the reference. Skip the further motion search on
// reconstructed frame if this error is small.
unscaled_last_source_buf_2d.buf =
cpi->unscaled_last_source->y_buffer + recon_yoffset;
unscaled_last_source_buf_2d.stride =
cpi->unscaled_last_source->y_stride;
raw_motion_error = get_prediction_error(bsize, &x->plane[0].src,
&unscaled_last_source_buf_2d);
// TODO(pengchong): Replace the hard-coded threshold
if (raw_motion_error > 25) {
// 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;
}
} 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.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 ? SVC_FACTOR_PT_LOW :
FACTOR_PT_LOW, FACTOR_PT_HIGH, 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 == VPX_CQ)
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);
TWO_PASS *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 a modified total error based upon
// the bias/power function used to allocate bits.
{
const double avg_error = stats->coded_error /
DOUBLE_DIVIDE_CHECK(stats->count);
const FIRSTPASS_STATS *s = twopass->stats_in;
double modified_error_total = 0.0;
twopass->modified_error_min = (avg_error *
oxcf->two_pass_vbrmin_section) / 100;
twopass->modified_error_max = (avg_error *
oxcf->two_pass_vbrmax_section) / 100;
while (s < twopass->stats_in_end) {
modified_error_total += calculate_modified_err(twopass, oxcf, s);
++s;
}
twopass->modified_error_left = modified_error_total;
}
// 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(TWO_PASS *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 TWO_PASS *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(const FIRSTPASS_STATS *stats,
double *mv_in_out,
double *mv_in_out_accumulator,
double *abs_mv_in_out_accumulator,
double *mv_ratio_accumulator) {
const double pct = stats->pcnt_motion;
// Accumulate Motion In/Out of frame stats.
*mv_in_out = stats->mv_in_out_count * pct;
*mv_in_out_accumulator += *mv_in_out;
*abs_mv_in_out_accumulator += fabs(*mv_in_out);
// Accumulate a measure of how uniform (or conversely how random) the motion
// field is (a ratio of abs(mv) / mv).
if (pct > 0.05) {
const double mvr_ratio = fabs(stats->mvr_abs) /
DOUBLE_DIVIDE_CHECK(fabs(stats->MVr));
const double mvc_ratio = fabs(stats->mvc_abs) /
DOUBLE_DIVIDE_CHECK(fabs(stats->MVc));
*mv_ratio_accumulator += pct * (mvr_ratio < stats->mvr_abs ?
mvr_ratio : stats->mvr_abs);
*mv_ratio_accumulator += pct * (mvc_ratio < stats->mvc_abs ?
mvc_ratio : stats->mvc_abs);
}
}
// Calculate a baseline boost number for the current frame.
static double calc_frame_boost(const TWO_PASS *twopass,
const 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 > twopass->gf_intra_err_min)
frame_boost = (IIFACTOR * this_frame->intra_error /
DOUBLE_DIVIDE_CHECK(this_frame->coded_error));
else
frame_boost = (IIFACTOR * 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;
TWO_PASS *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(twopass, &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(twopass, &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
// Calculate a section intra ratio used in setting max loop filter.
static int calculate_section_intra_ratio(const FIRSTPASS_STATS *begin,
const FIRSTPASS_STATS *end,
int section_length) {
const FIRSTPASS_STATS *s = begin;
double intra_error = 0.0;
double coded_error = 0.0;
int i = 0;
while (s < end && i < section_length) {
intra_error += s->intra_error;
coded_error += s->coded_error;
++s;
++i;
}
return (int)(intra_error / DOUBLE_DIVIDE_CHECK(coded_error));
}
// Calculate the total bits to allocate in this GF/ARF group.
static int64_t calculate_total_gf_group_bits(VP9_COMP *cpi,
double gf_group_err) {
const RATE_CONTROL *const rc = &cpi->rc;
const TWO_PASS *const twopass = &cpi->twopass;
const int max_bits = frame_max_bits(rc, &cpi->oxcf);
int64_t total_group_bits;
// Calculate the bits to be allocated to the group as a whole.
if ((twopass->kf_group_bits > 0) && (twopass->kf_group_error_left > 0)) {
total_group_bits = (int64_t)(twopass->kf_group_bits *
(gf_group_err / twopass->kf_group_error_left));
} else {
total_group_bits = 0;
}
// Clamp odd edge cases.
total_group_bits = (total_group_bits < 0) ?
0 : (total_group_bits > twopass->kf_group_bits) ?
twopass->kf_group_bits : total_group_bits;
// Clip based on user supplied data rate variability limit.
if (total_group_bits > (int64_t)max_bits * rc->baseline_gf_interval)
total_group_bits = (int64_t)max_bits * rc->baseline_gf_interval;
return total_group_bits;
}
// Calculate the number bits extra to assign to boosted frames in a group.
static int calculate_boost_bits(int frame_count,
int boost, int64_t total_group_bits) {
int allocation_chunks;
// return 0 for invalid inputs (could arise e.g. through rounding errors)
if (!boost || (total_group_bits <= 0) || (frame_count <= 0) )
return 0;
allocation_chunks = (frame_count * 100) + boost;
// Prevent overflow.
if (boost > 1023) {
int divisor = boost >> 10;
boost /= divisor;
allocation_chunks /= divisor;
}
// Calculate the number of extra bits for use in the boosted frame or frames.
return MAX((int)(((int64_t)boost * total_group_bits) / allocation_chunks), 0);
}
static void allocate_gf_group_bits(VP9_COMP *cpi, int64_t gf_group_bits,
double group_error, int gf_arf_bits) {
RATE_CONTROL *const rc = &cpi->rc;
const VP9EncoderConfig *const oxcf = &cpi->oxcf;
TWO_PASS *twopass = &cpi->twopass;
FIRSTPASS_STATS frame_stats;
int i;
int group_frame_index = 1;
int target_frame_size;
int key_frame;
const int max_bits = frame_max_bits(&cpi->rc, &cpi->oxcf);
int64_t total_group_bits = gf_group_bits;
double modified_err = 0.0;
double err_fraction;
key_frame = cpi->common.frame_type == KEY_FRAME ||
vp9_is_upper_layer_key_frame(cpi);
// For key frames the frame target rate is already set and it
// is also the golden frame.
// NOTE: We dont bother to check for the special case of ARF overlay
// frames here, as there is clamping code for this in the function
// vp9_rc_clamp_pframe_target_size(), which applies to one and two pass
// encodes.
if (!key_frame) {
twopass->gf_group_bit_allocation[0] = gf_arf_bits;
// Step over the golden frame / overlay frame
if (EOF == input_stats(twopass, &frame_stats))
return;
}
// Store the bits to spend on the ARF if there is one.
if (rc->source_alt_ref_pending) {
twopass->gf_group_bit_allocation[group_frame_index++] = gf_arf_bits;
}
// Deduct the boost bits for arf or gf if it is not a key frame.
if (rc->source_alt_ref_pending || !key_frame)
total_group_bits -= gf_arf_bits;
// Allocate bits to the other frames in the group.
for (i = 0; i < rc->baseline_gf_interval - 1; ++i) {
if (EOF == input_stats(twopass, &frame_stats))
break;
modified_err = calculate_modified_err(twopass, oxcf, &frame_stats);
if (group_error > 0)
err_fraction = modified_err / DOUBLE_DIVIDE_CHECK(group_error);
else
err_fraction = 0.0;
target_frame_size = (int)((double)total_group_bits * err_fraction);
target_frame_size = clamp(target_frame_size, 0,
MIN(max_bits, (int)total_group_bits));
twopass->gf_group_bit_allocation[group_frame_index++] = target_frame_size;
}
}
// 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;
TWO_PASS *const twopass = &cpi->twopass;
FIRSTPASS_STATS next_frame;
const FIRSTPASS_STATS *const start_pos = twopass->stats_in;
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;
unsigned int allow_alt_ref = is_altref_enabled(oxcf);
int f_boost = 0;
int b_boost = 0;
int flash_detected;
int active_max_gf_interval;
int64_t gf_group_bits;
double gf_group_error_left;
int gf_arf_bits;
// Reset the GF group data structures unless this is a key
// frame in which case it will already have been done.
if (cpi->common.frame_type != KEY_FRAME) {
twopass->gf_group_index = 0;
vp9_zero(twopass->gf_group_bit_allocation);
}
vp9_clear_system_state();
vp9_zero(next_frame);
gf_group_bits = 0;
// Load stats for the current frame.
mod_frame_err = calculate_modified_err(twopass, oxcf, 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(twopass, oxcf, 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(twopass, &next_frame,
this_frame_mv_in_out);
// Break out conditions.
if (
// Break at active_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(twopass, oxcf, 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
// Reset the file position.
reset_fpf_position(twopass, start_pos);
// Calculate the bits to be allocated to the gf/arf group as a whole
gf_group_bits = calculate_total_gf_group_bits(cpi, gf_group_err);
// Calculate the extra bits to be used for boosted frame(s)
{
int q = rc->last_q[INTER_FRAME];
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);
// Calculate the extra bits to be used for boosted frame(s)
gf_arf_bits = calculate_boost_bits(rc->baseline_gf_interval,
boost, gf_group_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) {
gf_group_error_left = gf_group_err - mod_frame_err;
} else if (cpi->common.frame_type != KEY_FRAME) {
gf_group_error_left = gf_group_err - gf_first_frame_err;
} else {
gf_group_error_left = gf_group_err;
}
// Allocate bits to each of the frames in the GF group.
allocate_gf_group_bits(cpi, gf_group_bits, gf_group_error_left, gf_arf_bits);
// Reset the file position.
reset_fpf_position(twopass, start_pos);
// Calculate a section intra ratio used in setting max loop filter.
if (cpi->common.frame_type != KEY_FRAME) {
twopass->section_intra_rating =
calculate_section_intra_ratio(start_pos, twopass->stats_in_end,
rc->baseline_gf_interval);
}
}
static int test_candidate_kf(TWO_PASS *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;
TWO_PASS *const twopass = &cpi->twopass;
const VP9EncoderConfig *const oxcf = &cpi->oxcf;
const FIRSTPASS_STATS first_frame = *this_frame;
const FIRSTPASS_STATS *const start_position = twopass->stats_in;
FIRSTPASS_STATS next_frame;
FIRSTPASS_STATS last_frame;
int kf_bits = 0;
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;
// Reset the GF group data structures.
twopass->gf_group_index = 0;
vp9_zero(twopass->gf_group_bit_allocation);
// 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(twopass, oxcf, 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(twopass, oxcf, 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(twopass, oxcf, &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(twopass, oxcf, 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;
}
twopass->kf_group_bits = MAX(0, twopass->kf_group_bits);
// Reset the first pass file position.
reset_fpf_position(twopass, start_position);
// Scan through the kf group collating various stats used to deteermine
// how many bits to spend on it.
decay_accumulator = 1.0;
boost_score = 0.0;
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);
}
}
reset_fpf_position(twopass, start_position);
// Store the zero motion percentage
twopass->kf_zeromotion_pct = (int)(zero_motion_accumulator * 100.0);
// Calculate a section intra ratio used in setting max loop filter.
twopass->section_intra_rating =
calculate_section_intra_ratio(start_position, twopass->stats_in_end,
rc->frames_to_key);
// Work out how many bits to allocate for the key frame itself.
rc->kf_boost = (int)boost_score;
if (rc->kf_boost < (rc->frames_to_key * 3))
rc->kf_boost = (rc->frames_to_key * 3);
if (rc->kf_boost < MIN_KF_BOOST)
rc->kf_boost = MIN_KF_BOOST;
kf_bits = calculate_boost_bits((rc->frames_to_key - 1),
rc->kf_boost, twopass->kf_group_bits);
twopass->kf_group_bits -= kf_bits;
// Save the bits to spend on the key frame.
twopass->gf_group_bit_allocation[0] = 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;
}
// 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;
TWO_PASS *const twopass = &cpi->twopass;
int frames_left;
FIRSTPASS_STATS this_frame;
FIRSTPASS_STATS this_frame_copy;
int target_rate;
LAYER_CONTEXT *lc = NULL;
const 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;
// Increment the gf group index.
++twopass->gf_group_index;
// If this is an arf frame then we dont want to read the stats file or
// advance the input pointer as we already have what we need.
if (cpi->refresh_alt_ref_frame) {
int target_rate;
target_rate = twopass->gf_group_bit_allocation[twopass->gf_group_index];
target_rate = vp9_rc_clamp_pframe_target_size(cpi, target_rate);
rc->base_frame_target = target_rate;
#ifdef LONG_TERM_VBR_CORRECTION
// Correction to rate target based on prior over or under shoot.
if (cpi->oxcf.rc_mode == VPX_VBR)
vbr_rate_correction(&target_rate, rc->vbr_bits_off_target);
#endif
vp9_rc_set_frame_target(cpi, target_rate);
cm->frame_type = INTER_FRAME;
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 == VPX_Q) {
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;
// Local copy of the current frame's first pass stats.
this_frame_copy = this_frame;
// Keyframe and section processing.
if (rc->frames_to_key == 0 ||
(cpi->frame_flags & FRAMEFLAGS_KEY)) {
// Define next KF group and assign bits to it.
find_next_key_frame(cpi, &this_frame_copy);
} else {
cm->frame_type = INTER_FRAME;
}
if (is_spatial_svc) {
if (cpi->svc.spatial_layer_id == 0) {
lc->is_key_frame = (cm->frame_type == KEY_FRAME);
} else {
cm->frame_type = INTER_FRAME;
lc->is_key_frame = cpi->svc.layer_context[0].is_key_frame;
if (lc->is_key_frame) {
cpi->ref_frame_flags &= (~VP9_LAST_FLAG);
}
}
}
// Define a new GF/ARF group. (Should always enter here for key frames).
if (rc->frames_till_gf_update_due == 0) {
#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;
}
{
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));
}
}
target_rate = twopass->gf_group_bit_allocation[twopass->gf_group_index];
if (cpi->common.frame_type == KEY_FRAME)
target_rate = vp9_rc_clamp_iframe_target_size(cpi, target_rate);
else
target_rate = vp9_rc_clamp_pframe_target_size(cpi, target_rate);
rc->base_frame_target = target_rate;
#ifdef LONG_TERM_VBR_CORRECTION
// Correction to rate target based on prior over or under shoot.
if (cpi->oxcf.rc_mode == VPX_VBR)
vbr_rate_correction(&target_rate, rc->vbr_bits_off_target);
#endif
vp9_rc_set_frame_target(cpi, target_rate);
// Update the total stats remaining structure.
subtract_stats(&twopass->total_left_stats, &this_frame);
}
void vp9_twopass_postencode_update(VP9_COMP *cpi) {
TWO_PASS *const twopass = &cpi->twopass;
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)(twopass->stats_in - twopass->stats_in_start) /
(twopass->stats_in_end - twopass->stats_in_start);
const int bits_used = (int)(progress * rc->this_frame_target +
(1.0 - progress) * rc->projected_frame_size);
#endif
twopass->bits_left = MAX(twopass->bits_left - bits_used, 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.
twopass->kf_group_bits += rc->this_frame_target - bits_used;
} else {
#endif
twopass->kf_group_bits -= bits_used;
}
twopass->kf_group_bits = MAX(twopass->kf_group_bits, 0);
}
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