ref: 9586d5e682683cc977f655e78b9ac937fc51eede
dir: /vp8/encoder/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 <math.h>
#include <limits.h>
#include <stdio.h>
#include "./vpx_dsp_rtcd.h"
#include "./vpx_scale_rtcd.h"
#include "block.h"
#include "onyx_int.h"
#include "vpx_dsp/variance.h"
#include "encodeintra.h"
#include "vp8/common/common.h"
#include "vp8/common/setupintrarecon.h"
#include "vp8/common/systemdependent.h"
#include "mcomp.h"
#include "firstpass.h"
#include "vpx_scale/vpx_scale.h"
#include "encodemb.h"
#include "vp8/common/extend.h"
#include "vpx_ports/system_state.h"
#include "vpx_mem/vpx_mem.h"
#include "vp8/common/swapyv12buffer.h"
#include "rdopt.h"
#include "vp8/common/quant_common.h"
#include "encodemv.h"
#include "encodeframe.h"
#define OUTPUT_FPF 0
extern void vp8cx_frame_init_quantizer(VP8_COMP *cpi);
#define GFQ_ADJUSTMENT vp8_gf_boost_qadjustment[Q]
extern int vp8_kf_boost_qadjustment[QINDEX_RANGE];
extern const int vp8_gf_boost_qadjustment[QINDEX_RANGE];
#define IIFACTOR 1.5
#define IIKFACTOR1 1.40
#define IIKFACTOR2 1.5
#define RMAX 14.0
#define GF_RMAX 48.0
#define KF_MB_INTRA_MIN 300
#define GF_MB_INTRA_MIN 200
#define DOUBLE_DIVIDE_CHECK(X) ((X) < 0 ? (X)-.000001 : (X) + .000001)
#define POW1 (double)cpi->oxcf.two_pass_vbrbias / 100.0
#define POW2 (double)cpi->oxcf.two_pass_vbrbias / 100.0
#define NEW_BOOST 1
static int vscale_lookup[7] = { 0, 1, 1, 2, 2, 3, 3 };
static int hscale_lookup[7] = { 0, 0, 1, 1, 2, 2, 3 };
static const int cq_level[QINDEX_RANGE] = {
0, 0, 1, 1, 2, 3, 3, 4, 4, 5, 6, 6, 7, 8, 8, 9, 9, 10, 11,
11, 12, 13, 13, 14, 15, 15, 16, 17, 17, 18, 19, 20, 20, 21, 22, 22, 23, 24,
24, 25, 26, 27, 27, 28, 29, 30, 30, 31, 32, 33, 33, 34, 35, 36, 36, 37, 38,
39, 39, 40, 41, 42, 42, 43, 44, 45, 46, 46, 47, 48, 49, 50, 50, 51, 52, 53,
54, 55, 55, 56, 57, 58, 59, 60, 60, 61, 62, 63, 64, 65, 66, 67, 67, 68, 69,
70, 71, 72, 73, 74, 75, 75, 76, 77, 78, 79, 80, 81, 82, 83, 84, 85, 86, 86,
87, 88, 89, 90, 91, 92, 93, 94, 95, 96, 97, 98, 99, 100
};
static void find_next_key_frame(VP8_COMP *cpi, FIRSTPASS_STATS *this_frame);
/* Resets the first pass file to the given position using a relative seek
* from the current position
*/
static void reset_fpf_position(VP8_COMP *cpi, FIRSTPASS_STATS *Position) {
cpi->twopass.stats_in = Position;
}
static int lookup_next_frame_stats(VP8_COMP *cpi, FIRSTPASS_STATS *next_frame) {
if (cpi->twopass.stats_in >= cpi->twopass.stats_in_end) return EOF;
*next_frame = *cpi->twopass.stats_in;
return 1;
}
/* Read frame stats at an offset from the current position */
static int read_frame_stats(VP8_COMP *cpi, FIRSTPASS_STATS *frame_stats,
int offset) {
FIRSTPASS_STATS *fps_ptr = cpi->twopass.stats_in;
/* Check legality of offset */
if (offset >= 0) {
if (&fps_ptr[offset] >= cpi->twopass.stats_in_end) return EOF;
} else if (offset < 0) {
if (&fps_ptr[offset] < cpi->twopass.stats_in_start) return EOF;
}
*frame_stats = fps_ptr[offset];
return 1;
}
static int input_stats(VP8_COMP *cpi, FIRSTPASS_STATS *fps) {
if (cpi->twopass.stats_in >= cpi->twopass.stats_in_end) return EOF;
*fps = *cpi->twopass.stats_in;
cpi->twopass.stats_in =
(void *)((char *)cpi->twopass.stats_in + sizeof(FIRSTPASS_STATS));
return 1;
}
static void output_stats(const VP8_COMP *cpi,
struct vpx_codec_pkt_list *pktlist,
FIRSTPASS_STATS *stats) {
struct vpx_codec_cx_pkt pkt;
(void)cpi;
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 %12.4f %12.4f %12.4f %12.4f"
" %12.4f %12.4f %12.4f %12.4f %12.4f %12.4f %12.4f %12.4f"
" %12.0f %12.0f %12.4f\n",
stats->frame, stats->intra_error, stats->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->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;
}
static void accumulate_stats(FIRSTPASS_STATS *section, FIRSTPASS_STATS *frame) {
section->frame += frame->frame;
section->intra_error += frame->intra_error;
section->coded_error += frame->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, FIRSTPASS_STATS *frame) {
section->frame -= frame->frame;
section->intra_error -= frame->intra_error;
section->coded_error -= frame->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->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(VP8_COMP *cpi,
FIRSTPASS_STATS *this_frame) {
double av_err = (cpi->twopass.total_stats.ssim_weighted_pred_err /
cpi->twopass.total_stats.count);
double this_err = this_frame->ssim_weighted_pred_err;
double modified_err;
if (this_err > av_err) {
modified_err = av_err * pow((this_err / DOUBLE_DIVIDE_CHECK(av_err)), POW1);
} else {
modified_err = av_err * pow((this_err / DOUBLE_DIVIDE_CHECK(av_err)), POW2);
}
return modified_err;
}
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(YV12_BUFFER_CONFIG *source) {
int i, j;
unsigned char *src = source->y_buffer;
double sum_weights = 0.0;
/* Loop throught the Y plane raw examining levels and creating a weight
* for the image
*/
i = source->y_height;
do {
j = source->y_width;
do {
sum_weights += weight_table[*src];
src++;
} while (--j);
src -= source->y_width;
src += source->y_stride;
} while (--i);
sum_weights /= (source->y_height * source->y_width);
return sum_weights;
}
/* This function returns the current per frame maximum bitrate target */
static int frame_max_bits(VP8_COMP *cpi) {
/* Max allocation for a single frame based on the max section guidelines
* passed in and how many bits are left
*/
int max_bits;
/* For CBR we need to also consider buffer fullness.
* If we are running below the optimal level then we need to gradually
* tighten up on max_bits.
*/
if (cpi->oxcf.end_usage == USAGE_STREAM_FROM_SERVER) {
double buffer_fullness_ratio =
(double)cpi->buffer_level /
DOUBLE_DIVIDE_CHECK((double)cpi->oxcf.optimal_buffer_level);
/* For CBR base this on the target average bits per frame plus the
* maximum sedction rate passed in by the user
*/
max_bits = (int)(cpi->av_per_frame_bandwidth *
((double)cpi->oxcf.two_pass_vbrmax_section / 100.0));
/* If our buffer is below the optimum level */
if (buffer_fullness_ratio < 1.0) {
/* The lower of max_bits / 4 or cpi->av_per_frame_bandwidth / 4. */
int min_max_bits = ((cpi->av_per_frame_bandwidth >> 2) < (max_bits >> 2))
? cpi->av_per_frame_bandwidth >> 2
: max_bits >> 2;
max_bits = (int)(max_bits * buffer_fullness_ratio);
/* Lowest value we will set ... which should allow the buffer to
* refill.
*/
if (max_bits < min_max_bits) max_bits = min_max_bits;
}
}
/* VBR */
else {
/* For VBR base this on the bits and frames left plus the
* two_pass_vbrmax_section rate passed in by the user
*/
max_bits = (int)(((double)cpi->twopass.bits_left /
(cpi->twopass.total_stats.count -
(double)cpi->common.current_video_frame)) *
((double)cpi->oxcf.two_pass_vbrmax_section / 100.0));
}
/* Trap case where we are out of bits */
if (max_bits < 0) max_bits = 0;
return max_bits;
}
void vp8_init_first_pass(VP8_COMP *cpi) {
zero_stats(&cpi->twopass.total_stats);
}
void vp8_end_first_pass(VP8_COMP *cpi) {
output_stats(cpi, cpi->output_pkt_list, &cpi->twopass.total_stats);
}
static void zz_motion_search(VP8_COMP *cpi, MACROBLOCK *x,
YV12_BUFFER_CONFIG *raw_buffer,
int *raw_motion_err,
YV12_BUFFER_CONFIG *recon_buffer,
int *best_motion_err, int recon_yoffset) {
MACROBLOCKD *const xd = &x->e_mbd;
BLOCK *b = &x->block[0];
BLOCKD *d = &x->e_mbd.block[0];
unsigned char *src_ptr = (*(b->base_src) + b->src);
int src_stride = b->src_stride;
unsigned char *raw_ptr;
int raw_stride = raw_buffer->y_stride;
unsigned char *ref_ptr;
int ref_stride = x->e_mbd.pre.y_stride;
(void)cpi;
/* Set up pointers for this macro block raw buffer */
raw_ptr = (unsigned char *)(raw_buffer->y_buffer + recon_yoffset + d->offset);
vpx_mse16x16(src_ptr, src_stride, raw_ptr, raw_stride,
(unsigned int *)(raw_motion_err));
/* Set up pointers for this macro block recon buffer */
xd->pre.y_buffer = recon_buffer->y_buffer + recon_yoffset;
ref_ptr = (unsigned char *)(xd->pre.y_buffer + d->offset);
vpx_mse16x16(src_ptr, src_stride, ref_ptr, ref_stride,
(unsigned int *)(best_motion_err));
}
static void first_pass_motion_search(VP8_COMP *cpi, MACROBLOCK *x,
int_mv *ref_mv, MV *best_mv,
YV12_BUFFER_CONFIG *recon_buffer,
int *best_motion_err, int recon_yoffset) {
MACROBLOCKD *const xd = &x->e_mbd;
BLOCK *b = &x->block[0];
BLOCKD *d = &x->e_mbd.block[0];
int num00;
int_mv tmp_mv;
int_mv ref_mv_full;
int tmp_err;
int step_param = 3; /* Dont search over full range for first pass */
int further_steps = (MAX_MVSEARCH_STEPS - 1) - step_param;
int n;
vp8_variance_fn_ptr_t v_fn_ptr = cpi->fn_ptr[BLOCK_16X16];
int new_mv_mode_penalty = 256;
/* override the default variance function to use MSE */
v_fn_ptr.vf = vpx_mse16x16;
/* Set up pointers for this macro block recon buffer */
xd->pre.y_buffer = recon_buffer->y_buffer + recon_yoffset;
/* Initial step/diamond search centred on best mv */
tmp_mv.as_int = 0;
ref_mv_full.as_mv.col = ref_mv->as_mv.col >> 3;
ref_mv_full.as_mv.row = ref_mv->as_mv.row >> 3;
tmp_err = cpi->diamond_search_sad(x, b, d, &ref_mv_full, &tmp_mv, step_param,
x->sadperbit16, &num00, &v_fn_ptr,
x->mvcost, ref_mv);
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->row = tmp_mv.as_mv.row;
best_mv->col = tmp_mv.as_mv.col;
}
/* 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, b, d, &ref_mv_full, &tmp_mv,
step_param + n, x->sadperbit16, &num00,
&v_fn_ptr, x->mvcost, ref_mv);
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->row = tmp_mv.as_mv.row;
best_mv->col = tmp_mv.as_mv.col;
}
}
}
}
void vp8_first_pass(VP8_COMP *cpi) {
int mb_row, mb_col;
MACROBLOCK *const x = &cpi->mb;
VP8_COMMON *const cm = &cpi->common;
MACROBLOCKD *const xd = &x->e_mbd;
int recon_yoffset, recon_uvoffset;
YV12_BUFFER_CONFIG *lst_yv12 = &cm->yv12_fb[cm->lst_fb_idx];
YV12_BUFFER_CONFIG *new_yv12 = &cm->yv12_fb[cm->new_fb_idx];
YV12_BUFFER_CONFIG *gld_yv12 = &cm->yv12_fb[cm->gld_fb_idx];
int recon_y_stride = lst_yv12->y_stride;
int recon_uv_stride = lst_yv12->uv_stride;
int64_t intra_error = 0;
int64_t coded_error = 0;
int sum_mvr = 0, sum_mvc = 0;
int sum_mvr_abs = 0, sum_mvc_abs = 0;
int 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;
int_mv zero_ref_mv;
zero_ref_mv.as_int = 0;
vpx_clear_system_state();
x->src = *cpi->Source;
xd->pre = *lst_yv12;
xd->dst = *new_yv12;
x->partition_info = x->pi;
xd->mode_info_context = cm->mi;
if (!cm->use_bilinear_mc_filter) {
xd->subpixel_predict = vp8_sixtap_predict4x4;
xd->subpixel_predict8x4 = vp8_sixtap_predict8x4;
xd->subpixel_predict8x8 = vp8_sixtap_predict8x8;
xd->subpixel_predict16x16 = vp8_sixtap_predict16x16;
} else {
xd->subpixel_predict = vp8_bilinear_predict4x4;
xd->subpixel_predict8x4 = vp8_bilinear_predict8x4;
xd->subpixel_predict8x8 = vp8_bilinear_predict8x8;
xd->subpixel_predict16x16 = vp8_bilinear_predict16x16;
}
vp8_build_block_offsets(x);
/* set up frame new frame for intra coded blocks */
vp8_setup_intra_recon(new_yv12);
vp8cx_frame_init_quantizer(cpi);
/* Initialise the MV cost table to the defaults */
{
int flag[2] = { 1, 1 };
vp8_initialize_rd_consts(cpi, x,
vp8_dc_quant(cm->base_qindex, cm->y1dc_delta_q));
memcpy(cm->fc.mvc, vp8_default_mv_context, sizeof(vp8_default_mv_context));
vp8_build_component_cost_table(cpi->mb.mvcost,
(const MV_CONTEXT *)cm->fc.mvc, flag);
}
/* for each macroblock row in image */
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 * 8);
/* Set up limit values for motion vectors to prevent them extending
* outside the UMV borders
*/
x->mv_row_min = -((mb_row * 16) + (VP8BORDERINPIXELS - 16));
x->mv_row_max =
((cm->mb_rows - 1 - mb_row) * 16) + (VP8BORDERINPIXELS - 16);
/* for each macroblock col in image */
for (mb_col = 0; mb_col < cm->mb_cols; ++mb_col) {
int this_error;
int gf_motion_error = INT_MAX;
int use_dc_pred = (mb_col || mb_row) && (!mb_col || !mb_row);
xd->dst.y_buffer = new_yv12->y_buffer + recon_yoffset;
xd->dst.u_buffer = new_yv12->u_buffer + recon_uvoffset;
xd->dst.v_buffer = new_yv12->v_buffer + recon_uvoffset;
xd->left_available = (mb_col != 0);
/* Copy current mb to a buffer */
vp8_copy_mem16x16(x->src.y_buffer, x->src.y_stride, x->thismb, 16);
/* do intra 16x16 prediction */
this_error = vp8_encode_intra(cpi, x, use_dc_pred);
/* "intrapenalty" below deals with situations where the intra
* and inter error scores are very low (eg 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 fot 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;
/* Cumulative intra error total */
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) + (VP8BORDERINPIXELS - 16));
x->mv_col_max =
((cm->mb_cols - 1 - mb_col) * 16) + (VP8BORDERINPIXELS - 16);
/* Other than for the first frame do a motion search */
if (cm->current_video_frame > 0) {
BLOCKD *d = &x->e_mbd.block[0];
MV tmp_mv = { 0, 0 };
int tmp_err;
int motion_error = INT_MAX;
int raw_motion_error = INT_MAX;
/* Simple 0,0 motion with no mv overhead */
zz_motion_search(cpi, x, cpi->last_frame_unscaled_source,
&raw_motion_error, lst_yv12, &motion_error,
recon_yoffset);
d->bmi.mv.as_mv.row = 0;
d->bmi.mv.as_mv.col = 0;
if (raw_motion_error < cpi->oxcf.encode_breakout) {
goto skip_motion_search;
}
/* 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, &d->bmi.mv.as_mv,
lst_yv12, &motion_error, recon_yoffset);
/* If the current best reference mv is not centred 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_ref_mv, &tmp_mv, lst_yv12,
&tmp_err, recon_yoffset);
if (tmp_err < motion_error) {
motion_error = tmp_err;
d->bmi.mv.as_mv.row = tmp_mv.row;
d->bmi.mv.as_mv.col = tmp_mv.col;
}
}
/* Experimental search in a second reference frame ((0,0)
* based only)
*/
if (cm->current_video_frame > 1) {
first_pass_motion_search(cpi, x, &zero_ref_mv, &tmp_mv, gld_yv12,
&gf_motion_error, recon_yoffset);
if ((gf_motion_error < motion_error) &&
(gf_motion_error < this_error)) {
second_ref_count++;
}
/* Reset to last frame as reference buffer */
xd->pre.y_buffer = lst_yv12->y_buffer + recon_yoffset;
xd->pre.u_buffer = lst_yv12->u_buffer + recon_uvoffset;
xd->pre.v_buffer = lst_yv12->v_buffer + recon_uvoffset;
}
skip_motion_search:
/* Intra assumed 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++;
}
d->bmi.mv.as_mv.row *= 8;
d->bmi.mv.as_mv.col *= 8;
this_error = motion_error;
vp8_set_mbmode_and_mvs(x, NEWMV, &d->bmi.mv);
vp8_encode_inter16x16y(x);
sum_mvr += d->bmi.mv.as_mv.row;
sum_mvr_abs += abs(d->bmi.mv.as_mv.row);
sum_mvc += d->bmi.mv.as_mv.col;
sum_mvc_abs += abs(d->bmi.mv.as_mv.col);
sum_mvrs += d->bmi.mv.as_mv.row * d->bmi.mv.as_mv.row;
sum_mvcs += d->bmi.mv.as_mv.col * d->bmi.mv.as_mv.col;
intercount++;
best_ref_mv.as_int = d->bmi.mv.as_int;
/* Was the vector non-zero */
if (d->bmi.mv.as_int) {
mvcount++;
/* Was it different from the last non zero vector */
if (d->bmi.mv.as_int != lastmv_as_int) new_mv_count++;
lastmv_as_int = d->bmi.mv.as_int;
/* Does the Row vector point inwards or outwards */
if (mb_row < cm->mb_rows / 2) {
if (d->bmi.mv.as_mv.row > 0) {
sum_in_vectors--;
} else if (d->bmi.mv.as_mv.row < 0) {
sum_in_vectors++;
}
} else if (mb_row > cm->mb_rows / 2) {
if (d->bmi.mv.as_mv.row > 0) {
sum_in_vectors++;
} else if (d->bmi.mv.as_mv.row < 0) {
sum_in_vectors--;
}
}
/* Does the Row vector point inwards or outwards */
if (mb_col < cm->mb_cols / 2) {
if (d->bmi.mv.as_mv.col > 0) {
sum_in_vectors--;
} else if (d->bmi.mv.as_mv.col < 0) {
sum_in_vectors++;
}
} else if (mb_col > cm->mb_cols / 2) {
if (d->bmi.mv.as_mv.col > 0) {
sum_in_vectors++;
} else if (d->bmi.mv.as_mv.col < 0) {
sum_in_vectors--;
}
}
}
}
}
coded_error += (int64_t)this_error;
/* adjust to the next column of macroblocks */
x->src.y_buffer += 16;
x->src.u_buffer += 8;
x->src.v_buffer += 8;
recon_yoffset += 16;
recon_uvoffset += 8;
}
/* adjust to the next row of mbs */
x->src.y_buffer += 16 * x->src.y_stride - 16 * cm->mb_cols;
x->src.u_buffer += 8 * x->src.uv_stride - 8 * cm->mb_cols;
x->src.v_buffer += 8 * x->src.uv_stride - 8 * cm->mb_cols;
/* extend the recon for intra prediction */
vp8_extend_mb_row(new_yv12, xd->dst.y_buffer + 16, xd->dst.u_buffer + 8,
xd->dst.v_buffer + 8);
vpx_clear_system_state();
}
vpx_clear_system_state();
{
double weight = 0.0;
FIRSTPASS_STATS fps;
fps.frame = cm->current_video_frame;
fps.intra_error = (double)(intra_error >> 8);
fps.coded_error = (double)(coded_error >> 8);
weight = simple_weight(cpi->Source);
if (weight < 0.1) weight = 0.1;
fps.ssim_weighted_pred_err = fps.coded_error * weight;
fps.pcnt_inter = 0.0;
fps.pcnt_motion = 0.0;
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.count = 1.0;
fps.pcnt_inter = 1.0 * (double)intercount / cm->MBs;
fps.pcnt_second_ref = 1.0 * (double)second_ref_count / cm->MBs;
fps.pcnt_neutral = 1.0 * (double)neutral_count / cm->MBs;
if (mvcount > 0) {
fps.MVr = (double)sum_mvr / (double)mvcount;
fps.mvr_abs = (double)sum_mvr_abs / (double)mvcount;
fps.MVc = (double)sum_mvc / (double)mvcount;
fps.mvc_abs = (double)sum_mvc_abs / (double)mvcount;
fps.MVrv = ((double)sum_mvrs - (fps.MVr * fps.MVr / (double)mvcount)) /
(double)mvcount;
fps.MVcv = ((double)sum_mvcs - (fps.MVc * fps.MVc / (double)mvcount)) /
(double)mvcount;
fps.mv_in_out_count = (double)sum_in_vectors / (double)(mvcount * 2);
fps.new_mv_count = new_mv_count;
fps.pcnt_motion = 1.0 * (double)mvcount / cpi->common.MBs;
}
/* TODO: handle the case when duration is set to 0, or something less
* than the full time between subsequent cpi->source_time_stamps
*/
fps.duration = (double)(cpi->source->ts_end - cpi->source->ts_start);
/* don't want to do output stats with a stack variable! */
memcpy(&cpi->twopass.this_frame_stats, &fps, sizeof(FIRSTPASS_STATS));
output_stats(cpi, cpi->output_pkt_list, &cpi->twopass.this_frame_stats);
accumulate_stats(&cpi->twopass.total_stats, &fps);
}
/* Copy the previous Last Frame into the GF buffer if specific
* conditions for doing so are met
*/
if ((cm->current_video_frame > 0) &&
(cpi->twopass.this_frame_stats.pcnt_inter > 0.20) &&
((cpi->twopass.this_frame_stats.intra_error /
DOUBLE_DIVIDE_CHECK(cpi->twopass.this_frame_stats.coded_error)) >
2.0)) {
vp8_yv12_copy_frame(lst_yv12, gld_yv12);
}
/* swap frame pointers so last frame refers to the frame we just
* compressed
*/
vp8_swap_yv12_buffer(lst_yv12, new_yv12);
vp8_yv12_extend_frame_borders(lst_yv12);
/* Special case for the first frame. Copy into the GF buffer as a
* second reference.
*/
if (cm->current_video_frame == 0) {
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;
sprintf(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++;
}
extern const int vp8_bits_per_mb[2][QINDEX_RANGE];
/* Estimate a cost per mb attributable to overheads such as the coding of
* modes and motion vectors.
* Currently simplistic in its assumptions for testing.
*/
static double bitcost(double prob) {
if (prob > 0.000122) {
return -log(prob) / log(2.0);
} else {
return 13.0;
}
}
static int64_t estimate_modemvcost(VP8_COMP *cpi, FIRSTPASS_STATS *fpstats) {
int mv_cost;
int64_t mode_cost;
double av_pct_inter = fpstats->pcnt_inter / fpstats->count;
double av_pct_motion = fpstats->pcnt_motion / fpstats->count;
double av_intra = (1.0 - av_pct_inter);
double zz_cost;
double motion_cost;
double intra_cost;
zz_cost = bitcost(av_pct_inter - av_pct_motion);
motion_cost = bitcost(av_pct_motion);
intra_cost = bitcost(av_intra);
/* Estimate of extra bits per mv overhead for mbs
* << 9 is the normalization to the (bits * 512) used in vp8_bits_per_mb
*/
mv_cost = ((int)(fpstats->new_mv_count / fpstats->count) * 8) << 9;
/* Crude estimate of overhead cost from modes
* << 9 is the normalization to (bits * 512) used in vp8_bits_per_mb
*/
mode_cost =
(int64_t)((((av_pct_inter - av_pct_motion) * zz_cost) +
(av_pct_motion * motion_cost) + (av_intra * intra_cost)) *
cpi->common.MBs) *
512;
return mv_cost + mode_cost;
}
static double calc_correction_factor(double err_per_mb, double err_devisor,
double pt_low, double pt_high, int Q) {
double power_term;
double error_term = err_per_mb / err_devisor;
double correction_factor;
/* Adjustment based on Q to power term. */
power_term = pt_low + (Q * 0.01);
power_term = (power_term > pt_high) ? pt_high : power_term;
/* Adjustments to error term */
/* TBD */
/* Calculate correction factor */
correction_factor = pow(error_term, power_term);
/* Clip range */
correction_factor = (correction_factor < 0.05)
? 0.05
: (correction_factor > 5.0) ? 5.0 : correction_factor;
return correction_factor;
}
static int estimate_max_q(VP8_COMP *cpi, FIRSTPASS_STATS *fpstats,
int section_target_bandwitdh, int overhead_bits) {
int Q;
int num_mbs = cpi->common.MBs;
int target_norm_bits_per_mb;
double section_err = (fpstats->coded_error / fpstats->count);
double err_per_mb = section_err / num_mbs;
double err_correction_factor;
double speed_correction = 1.0;
int overhead_bits_per_mb;
if (section_target_bandwitdh <= 0) {
return cpi->twopass.maxq_max_limit; /* Highest value allowed */
}
target_norm_bits_per_mb = (section_target_bandwitdh < (1 << 20))
? (512 * section_target_bandwitdh) / num_mbs
: 512 * (section_target_bandwitdh / num_mbs);
/* Calculate a corrective factor based on a rolling ratio of bits spent
* vs target bits
*/
if ((cpi->rolling_target_bits > 0) &&
(cpi->active_worst_quality < cpi->worst_quality)) {
double rolling_ratio;
rolling_ratio =
(double)cpi->rolling_actual_bits / (double)cpi->rolling_target_bits;
if (rolling_ratio < 0.95) {
cpi->twopass.est_max_qcorrection_factor -= 0.005;
} else if (rolling_ratio > 1.05) {
cpi->twopass.est_max_qcorrection_factor += 0.005;
}
cpi->twopass.est_max_qcorrection_factor =
(cpi->twopass.est_max_qcorrection_factor < 0.1)
? 0.1
: (cpi->twopass.est_max_qcorrection_factor > 10.0)
? 10.0
: cpi->twopass.est_max_qcorrection_factor;
}
/* Corrections for higher compression speed settings
* (reduced compression expected)
*/
if ((cpi->compressor_speed == 3) || (cpi->compressor_speed == 1)) {
if (cpi->oxcf.cpu_used <= 5) {
speed_correction = 1.04 + (cpi->oxcf.cpu_used * 0.04);
} else {
speed_correction = 1.25;
}
}
/* Estimate of overhead bits per mb */
/* Correction to overhead bits for min allowed Q. */
overhead_bits_per_mb = overhead_bits / num_mbs;
overhead_bits_per_mb = (int)(overhead_bits_per_mb *
pow(0.98, (double)cpi->twopass.maxq_min_limit));
/* Try and pick a max Q that will be high enough to encode the
* content at the given rate.
*/
for (Q = cpi->twopass.maxq_min_limit; Q < cpi->twopass.maxq_max_limit; ++Q) {
int bits_per_mb_at_this_q;
/* Error per MB based correction factor */
err_correction_factor =
calc_correction_factor(err_per_mb, 150.0, 0.40, 0.90, Q);
bits_per_mb_at_this_q =
vp8_bits_per_mb[INTER_FRAME][Q] + overhead_bits_per_mb;
bits_per_mb_at_this_q = (int)(.5 +
err_correction_factor * speed_correction *
cpi->twopass.est_max_qcorrection_factor *
cpi->twopass.section_max_qfactor *
(double)bits_per_mb_at_this_q);
/* Mode and motion overhead */
/* As Q rises in real encode loop rd code will force overhead down
* We make a crude adjustment for this here as *.98 per Q step.
*/
overhead_bits_per_mb = (int)((double)overhead_bits_per_mb * 0.98);
if (bits_per_mb_at_this_q <= target_norm_bits_per_mb) break;
}
/* Restriction on active max q for constrained quality mode. */
if ((cpi->oxcf.end_usage == USAGE_CONSTRAINED_QUALITY) &&
(Q < cpi->cq_target_quality)) {
Q = cpi->cq_target_quality;
}
/* Adjust maxq_min_limit and maxq_max_limit limits based on
* average q observed in clip for non kf/gf.arf frames
* Give average a chance to settle though.
*/
if ((cpi->ni_frames > ((int)cpi->twopass.total_stats.count >> 8)) &&
(cpi->ni_frames > 150)) {
cpi->twopass.maxq_max_limit = ((cpi->ni_av_qi + 32) < cpi->worst_quality)
? (cpi->ni_av_qi + 32)
: cpi->worst_quality;
cpi->twopass.maxq_min_limit = ((cpi->ni_av_qi - 32) > cpi->best_quality)
? (cpi->ni_av_qi - 32)
: cpi->best_quality;
}
return Q;
}
/* For cq mode estimate a cq level that matches the observed
* complexity and data rate.
*/
static int estimate_cq(VP8_COMP *cpi, FIRSTPASS_STATS *fpstats,
int section_target_bandwitdh, int overhead_bits) {
int Q;
int num_mbs = cpi->common.MBs;
int target_norm_bits_per_mb;
double section_err = (fpstats->coded_error / fpstats->count);
double err_per_mb = section_err / num_mbs;
double err_correction_factor;
double speed_correction = 1.0;
double clip_iiratio;
double clip_iifactor;
int overhead_bits_per_mb;
if (0) {
FILE *f = fopen("epmp.stt", "a");
fprintf(f, "%10.2f\n", err_per_mb);
fclose(f);
}
target_norm_bits_per_mb = (section_target_bandwitdh < (1 << 20))
? (512 * section_target_bandwitdh) / num_mbs
: 512 * (section_target_bandwitdh / num_mbs);
/* Estimate of overhead bits per mb */
overhead_bits_per_mb = overhead_bits / num_mbs;
/* Corrections for higher compression speed settings
* (reduced compression expected)
*/
if ((cpi->compressor_speed == 3) || (cpi->compressor_speed == 1)) {
if (cpi->oxcf.cpu_used <= 5) {
speed_correction = 1.04 + (cpi->oxcf.cpu_used * 0.04);
} else {
speed_correction = 1.25;
}
}
/* II ratio correction factor for clip as a whole */
clip_iiratio = cpi->twopass.total_stats.intra_error /
DOUBLE_DIVIDE_CHECK(cpi->twopass.total_stats.coded_error);
clip_iifactor = 1.0 - ((clip_iiratio - 10.0) * 0.025);
if (clip_iifactor < 0.80) clip_iifactor = 0.80;
/* Try and pick a Q that can encode the content at the given rate. */
for (Q = 0; Q < MAXQ; ++Q) {
int bits_per_mb_at_this_q;
/* Error per MB based correction factor */
err_correction_factor =
calc_correction_factor(err_per_mb, 100.0, 0.40, 0.90, Q);
bits_per_mb_at_this_q =
vp8_bits_per_mb[INTER_FRAME][Q] + overhead_bits_per_mb;
bits_per_mb_at_this_q =
(int)(.5 +
err_correction_factor * speed_correction * clip_iifactor *
(double)bits_per_mb_at_this_q);
/* Mode and motion overhead */
/* As Q rises in real encode loop rd code will force overhead down
* We make a crude adjustment for this here as *.98 per Q step.
*/
overhead_bits_per_mb = (int)((double)overhead_bits_per_mb * 0.98);
if (bits_per_mb_at_this_q <= target_norm_bits_per_mb) break;
}
/* Clip value to range "best allowed to (worst allowed - 1)" */
Q = cq_level[Q];
if (Q >= cpi->worst_quality) Q = cpi->worst_quality - 1;
if (Q < cpi->best_quality) Q = cpi->best_quality;
return Q;
}
static int estimate_q(VP8_COMP *cpi, double section_err,
int section_target_bandwitdh) {
int Q;
int num_mbs = cpi->common.MBs;
int target_norm_bits_per_mb;
double err_per_mb = section_err / num_mbs;
double err_correction_factor;
double speed_correction = 1.0;
target_norm_bits_per_mb = (section_target_bandwitdh < (1 << 20))
? (512 * section_target_bandwitdh) / num_mbs
: 512 * (section_target_bandwitdh / num_mbs);
/* Corrections for higher compression speed settings
* (reduced compression expected)
*/
if ((cpi->compressor_speed == 3) || (cpi->compressor_speed == 1)) {
if (cpi->oxcf.cpu_used <= 5) {
speed_correction = 1.04 + (cpi->oxcf.cpu_used * 0.04);
} else {
speed_correction = 1.25;
}
}
/* Try and pick a Q that can encode the content at the given rate. */
for (Q = 0; Q < MAXQ; ++Q) {
int bits_per_mb_at_this_q;
/* Error per MB based correction factor */
err_correction_factor =
calc_correction_factor(err_per_mb, 150.0, 0.40, 0.90, Q);
bits_per_mb_at_this_q =
(int)(.5 + (err_correction_factor * speed_correction *
cpi->twopass.est_max_qcorrection_factor *
(double)vp8_bits_per_mb[INTER_FRAME][Q] / 1.0));
if (bits_per_mb_at_this_q <= target_norm_bits_per_mb) break;
}
return Q;
}
/* Estimate a worst case Q for a KF group */
static int estimate_kf_group_q(VP8_COMP *cpi, double section_err,
int section_target_bandwitdh,
double group_iiratio) {
int Q;
int num_mbs = cpi->common.MBs;
int target_norm_bits_per_mb = (512 * section_target_bandwitdh) / num_mbs;
int bits_per_mb_at_this_q;
double err_per_mb = section_err / num_mbs;
double err_correction_factor;
double speed_correction = 1.0;
double current_spend_ratio = 1.0;
double pow_highq = (POW1 < 0.6) ? POW1 + 0.3 : 0.90;
double pow_lowq = (POW1 < 0.7) ? POW1 + 0.1 : 0.80;
double iiratio_correction_factor = 1.0;
double combined_correction_factor;
/* Trap special case where the target is <= 0 */
if (target_norm_bits_per_mb <= 0) return MAXQ * 2;
/* Calculate a corrective factor based on a rolling ratio of bits spent
* vs target bits
* This is clamped to the range 0.1 to 10.0
*/
if (cpi->long_rolling_target_bits <= 0) {
current_spend_ratio = 10.0;
} else {
current_spend_ratio = (double)cpi->long_rolling_actual_bits /
(double)cpi->long_rolling_target_bits;
current_spend_ratio =
(current_spend_ratio > 10.0)
? 10.0
: (current_spend_ratio < 0.1) ? 0.1 : current_spend_ratio;
}
/* Calculate a correction factor based on the quality of prediction in
* the sequence as indicated by intra_inter error score ratio (IIRatio)
* The idea here is to favour subsampling in the hardest sections vs
* the easyest.
*/
iiratio_correction_factor = 1.0 - ((group_iiratio - 6.0) * 0.1);
if (iiratio_correction_factor < 0.5) iiratio_correction_factor = 0.5;
/* Corrections for higher compression speed settings
* (reduced compression expected)
*/
if ((cpi->compressor_speed == 3) || (cpi->compressor_speed == 1)) {
if (cpi->oxcf.cpu_used <= 5) {
speed_correction = 1.04 + (cpi->oxcf.cpu_used * 0.04);
} else {
speed_correction = 1.25;
}
}
/* Combine the various factors calculated above */
combined_correction_factor =
speed_correction * iiratio_correction_factor * current_spend_ratio;
/* Try and pick a Q that should be high enough to encode the content at
* the given rate.
*/
for (Q = 0; Q < MAXQ; ++Q) {
/* Error per MB based correction factor */
err_correction_factor =
calc_correction_factor(err_per_mb, 150.0, pow_lowq, pow_highq, Q);
bits_per_mb_at_this_q =
(int)(.5 + (err_correction_factor * combined_correction_factor *
(double)vp8_bits_per_mb[INTER_FRAME][Q]));
if (bits_per_mb_at_this_q <= target_norm_bits_per_mb) break;
}
/* If we could not hit the target even at Max Q then estimate what Q
* would have been required
*/
while ((bits_per_mb_at_this_q > target_norm_bits_per_mb) &&
(Q < (MAXQ * 2))) {
bits_per_mb_at_this_q = (int)(0.96 * bits_per_mb_at_this_q);
Q++;
}
if (0) {
FILE *f = fopen("estkf_q.stt", "a");
fprintf(f, "%8d %8d %8d %8.2f %8.3f %8.2f %8.3f %8.3f %8.3f %8d\n",
cpi->common.current_video_frame, bits_per_mb_at_this_q,
target_norm_bits_per_mb, err_per_mb, err_correction_factor,
current_spend_ratio, group_iiratio, iiratio_correction_factor,
(double)cpi->buffer_level / (double)cpi->oxcf.optimal_buffer_level,
Q);
fclose(f);
}
return Q;
}
void vp8_init_second_pass(VP8_COMP *cpi) {
FIRSTPASS_STATS this_frame;
FIRSTPASS_STATS *start_pos;
double two_pass_min_rate = (double)(cpi->oxcf.target_bandwidth *
cpi->oxcf.two_pass_vbrmin_section / 100);
zero_stats(&cpi->twopass.total_stats);
zero_stats(&cpi->twopass.total_left_stats);
if (!cpi->twopass.stats_in_end) return;
cpi->twopass.total_stats = *cpi->twopass.stats_in_end;
cpi->twopass.total_left_stats = cpi->twopass.total_stats;
/* 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. Its calculated based on the actual durations of
* all frames from the first pass.
*/
vp8_new_framerate(cpi, 10000000.0 * cpi->twopass.total_stats.count /
cpi->twopass.total_stats.duration);
cpi->output_framerate = cpi->framerate;
cpi->twopass.bits_left = (int64_t)(cpi->twopass.total_stats.duration *
cpi->oxcf.target_bandwidth / 10000000.0);
cpi->twopass.bits_left -= (int64_t)(cpi->twopass.total_stats.duration *
two_pass_min_rate / 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
*/
cpi->twopass.kf_intra_err_min = KF_MB_INTRA_MIN * cpi->common.MBs;
cpi->twopass.gf_intra_err_min = GF_MB_INTRA_MIN * cpi->common.MBs;
/* Scan the first pass file and calculate an average Intra / Inter error
* score ratio for the sequence
*/
{
double sum_iiratio = 0.0;
double IIRatio;
start_pos = cpi->twopass.stats_in; /* Note starting "file" position */
while (input_stats(cpi, &this_frame) != EOF) {
IIRatio =
this_frame.intra_error / DOUBLE_DIVIDE_CHECK(this_frame.coded_error);
IIRatio = (IIRatio < 1.0) ? 1.0 : (IIRatio > 20.0) ? 20.0 : IIRatio;
sum_iiratio += IIRatio;
}
cpi->twopass.avg_iiratio =
sum_iiratio /
DOUBLE_DIVIDE_CHECK((double)cpi->twopass.total_stats.count);
/* Reset file position */
reset_fpf_position(cpi, start_pos);
}
/* Scan the first pass file and calculate a modified total error based
* upon the bias/power function used to allocate bits
*/
{
start_pos = cpi->twopass.stats_in; /* Note starting "file" position */
cpi->twopass.modified_error_total = 0.0;
cpi->twopass.modified_error_used = 0.0;
while (input_stats(cpi, &this_frame) != EOF) {
cpi->twopass.modified_error_total +=
calculate_modified_err(cpi, &this_frame);
}
cpi->twopass.modified_error_left = cpi->twopass.modified_error_total;
reset_fpf_position(cpi, start_pos); /* Reset file position */
}
}
void vp8_end_second_pass(VP8_COMP *cpi) { (void)cpi; }
/* This function gives and estimate of how badly we believe the prediction
* quality is decaying from frame to frame.
*/
static double get_prediction_decay_rate(VP8_COMP *cpi,
FIRSTPASS_STATS *next_frame) {
double prediction_decay_rate;
double motion_decay;
double motion_pct = next_frame->pcnt_motion;
(void)cpi;
/* Initial basis is the % mbs inter coded */
prediction_decay_rate = next_frame->pcnt_inter;
/* High % motion -> somewhat higher decay rate */
motion_decay = (1.0 - (motion_pct / 20.0));
if (motion_decay < prediction_decay_rate) {
prediction_decay_rate = motion_decay;
}
/* Adjustment to decay rate based on speed of motion */
{
double this_mv_rabs;
double this_mv_cabs;
double distance_factor;
this_mv_rabs = fabs(next_frame->mvr_abs * motion_pct);
this_mv_cabs = fabs(next_frame->mvc_abs * motion_pct);
distance_factor =
sqrt((this_mv_rabs * this_mv_rabs) + (this_mv_cabs * this_mv_cabs)) /
250.0;
distance_factor = ((distance_factor > 1.0) ? 0.0 : (1.0 - distance_factor));
if (distance_factor < prediction_decay_rate) {
prediction_decay_rate = distance_factor;
}
}
return prediction_decay_rate;
}
/* 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(VP8_COMP *cpi, int frame_interval,
int still_interval,
double loop_decay_rate,
double decay_accumulator) {
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) &&
(decay_accumulator < 0.9)) {
int j;
FIRSTPASS_STATS *position = cpi->twopass.stats_in;
FIRSTPASS_STATS tmp_next_frame;
double decay_rate;
/* Look ahead a few frames to see if static condition persists... */
for (j = 0; j < still_interval; ++j) {
if (EOF == input_stats(cpi, &tmp_next_frame)) break;
decay_rate = get_prediction_decay_rate(cpi, &tmp_next_frame);
if (decay_rate < 0.999) break;
}
/* Reset file position */
reset_fpf_position(cpi, 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(VP8_COMP *cpi, int offset) {
FIRSTPASS_STATS next_frame;
int flash_detected = 0;
/* Read the frame data. */
/* The return is 0 (no flash detected) if not a valid frame */
if (read_frame_stats(cpi, &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
* comapred to pcnt_inter.
*/
if ((next_frame.pcnt_second_ref > next_frame.pcnt_inter) &&
(next_frame.pcnt_second_ref >= 0.5)) {
flash_detected = 1;
/*if (1)
{
FILE *f = fopen("flash.stt", "a");
fprintf(f, "%8.0f %6.2f %6.2f\n",
next_frame.frame,
next_frame.pcnt_inter,
next_frame.pcnt_second_ref);
fclose(f);
}*/
}
}
return flash_detected;
}
/* Update the motion related elements to the GF arf boost calculation */
static void accumulate_frame_motion_stats(VP8_COMP *cpi,
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 this_frame_mvr_ratio;
double this_frame_mvc_ratio;
double motion_pct;
(void)cpi;
/* 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) {
this_frame_mvr_ratio =
fabs(this_frame->mvr_abs) / DOUBLE_DIVIDE_CHECK(fabs(this_frame->MVr));
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(VP8_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
* (eg 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 extreme case boost is halved */
} else {
frame_boost += frame_boost * (this_frame_mv_in_out / 2.0);
}
/* Clip to maximum */
if (frame_boost > GF_RMAX) frame_boost = GF_RMAX;
return frame_boost;
}
#if NEW_BOOST
static int calc_arf_boost(VP8_COMP *cpi, int offset, int f_frames, int b_frames,
int *f_boost, int *b_boost) {
FIRSTPASS_STATS this_frame;
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;
double r;
int flash_detected = 0;
/* Search forward from the proposed arf/next gf position */
for (i = 0; i < f_frames; ++i) {
if (read_frame_stats(cpi, &this_frame, (i + offset)) == EOF) break;
/* Update the motion related elements to the boost calculation */
accumulate_frame_motion_stats(
cpi, &this_frame, &this_frame_mv_in_out, &mv_in_out_accumulator,
&abs_mv_in_out_accumulator, &mv_ratio_accumulator);
/* Calculate the baseline boost number for this frame */
r = calc_frame_boost(cpi, &this_frame, this_frame_mv_in_out);
/* 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(cpi, (i + offset)) || detect_flash(cpi, (i + offset + 1));
/* Cumulative effect of prediction quality decay */
if (!flash_detected) {
decay_accumulator =
decay_accumulator * get_prediction_decay_rate(cpi, &this_frame);
decay_accumulator = decay_accumulator < 0.1 ? 0.1 : decay_accumulator;
}
boost_score += (decay_accumulator * r);
/* Break out conditions. */
if ((!flash_detected) &&
((mv_ratio_accumulator > 100.0) || (abs_mv_in_out_accumulator > 3.0) ||
(mv_in_out_accumulator < -2.0))) {
break;
}
}
*f_boost = (int)(boost_score * 100.0) >> 4;
/* 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 forward from the proposed arf/next gf position */
for (i = -1; i >= -b_frames; i--) {
if (read_frame_stats(cpi, &this_frame, (i + offset)) == EOF) break;
/* Update the motion related elements to the boost calculation */
accumulate_frame_motion_stats(
cpi, &this_frame, &this_frame_mv_in_out, &mv_in_out_accumulator,
&abs_mv_in_out_accumulator, &mv_ratio_accumulator);
/* Calculate the baseline boost number for this frame */
r = calc_frame_boost(cpi, &this_frame, this_frame_mv_in_out);
/* 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(cpi, (i + offset)) || detect_flash(cpi, (i + offset + 1));
/* Cumulative effect of prediction quality decay */
if (!flash_detected) {
decay_accumulator =
decay_accumulator * get_prediction_decay_rate(cpi, &this_frame);
decay_accumulator = decay_accumulator < 0.1 ? 0.1 : decay_accumulator;
}
boost_score += (decay_accumulator * r);
/* Break out conditions. */
if ((!flash_detected) &&
((mv_ratio_accumulator > 100.0) || (abs_mv_in_out_accumulator > 3.0) ||
(mv_in_out_accumulator < -2.0))) {
break;
}
}
*b_boost = (int)(boost_score * 100.0) >> 4;
return (*f_boost + *b_boost);
}
#endif
/* Analyse and define a gf/arf group . */
static void define_gf_group(VP8_COMP *cpi, FIRSTPASS_STATS *this_frame) {
FIRSTPASS_STATS next_frame;
FIRSTPASS_STATS *start_pos;
int i;
double r;
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 loop_decay_rate = 1.00; /* Starting decay rate */
double this_frame_mv_in_out = 0.0;
double mv_in_out_accumulator = 0.0;
double abs_mv_in_out_accumulator = 0.0;
double mod_err_per_mb_accumulator = 0.0;
int max_bits = frame_max_bits(cpi); /* Max for a single frame */
unsigned int allow_alt_ref =
cpi->oxcf.play_alternate && cpi->oxcf.lag_in_frames;
int alt_boost = 0;
int f_boost = 0;
int b_boost = 0;
int flash_detected;
cpi->twopass.gf_group_bits = 0;
cpi->twopass.gf_decay_rate = 0;
vpx_clear_system_state();
start_pos = cpi->twopass.stats_in;
memset(&next_frame, 0, sizeof(next_frame)); /* assure clean */
/* 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;
/* Special treatment if the current frame is a key frame (which is also
* a gf). If it is then its error score (and hence bit allocation) need
* to be subtracted out from the calculation for the GF group
*/
if (cpi->common.frame_type == KEY_FRAME) gf_group_err -= gf_first_frame_err;
/* Scan forward to try and work out how many frames the next gf group
* should contain and what level of boost is appropriate for the GF
* or ARF that will be coded with the group
*/
i = 0;
while (((i < cpi->twopass.static_scene_max_gf_interval) ||
((cpi->twopass.frames_to_key - i) < MIN_GF_INTERVAL)) &&
(i < cpi->twopass.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;
mod_err_per_mb_accumulator +=
mod_frame_err / DOUBLE_DIVIDE_CHECK((double)cpi->common.MBs);
if (EOF == input_stats(cpi, &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(cpi, 0);
/* Update the motion related elements to the boost calculation */
accumulate_frame_motion_stats(
cpi, &next_frame, &this_frame_mv_in_out, &mv_in_out_accumulator,
&abs_mv_in_out_accumulator, &mv_ratio_accumulator);
/* Calculate a baseline boost number for this frame */
r = calc_frame_boost(cpi, &next_frame, this_frame_mv_in_out);
/* Cumulative effect of prediction quality decay */
if (!flash_detected) {
loop_decay_rate = get_prediction_decay_rate(cpi, &next_frame);
decay_accumulator = decay_accumulator * loop_decay_rate;
decay_accumulator = decay_accumulator < 0.1 ? 0.1 : decay_accumulator;
}
boost_score += (decay_accumulator * r);
/* Break clause to detect very still sections after motion
* For example a staic image after a fade or other transition.
*/
if (detect_transition_to_still(cpi, i, 5, loop_decay_rate,
decay_accumulator)) {
allow_alt_ref = 0;
boost_score = old_boost_score;
break;
}
/* Break out conditions. */
if (
/* Break at cpi->max_gf_interval unless almost totally static */
(i >= cpi->max_gf_interval && (decay_accumulator < 0.995)) ||
(
/* Dont break out with a very short interval */
(i > MIN_GF_INTERVAL) &&
/* Dont break out very close to a key frame */
((cpi->twopass.frames_to_key - i) >= MIN_GF_INTERVAL) &&
((boost_score > 20.0) || (next_frame.pcnt_inter < 0.75)) &&
(!flash_detected) && ((mv_ratio_accumulator > 100.0) ||
(abs_mv_in_out_accumulator > 3.0) ||
(mv_in_out_accumulator < -2.0) ||
((boost_score - old_boost_score) < 2.0)))) {
boost_score = old_boost_score;
break;
}
memcpy(this_frame, &next_frame, sizeof(*this_frame));
old_boost_score = boost_score;
}
cpi->twopass.gf_decay_rate =
(i > 0) ? (int)(100.0 * (1.0 - decay_accumulator)) / i : 0;
/* When using CBR apply additional buffer related upper limits */
if (cpi->oxcf.end_usage == USAGE_STREAM_FROM_SERVER) {
double max_boost;
/* For cbr apply buffer related limits */
if (cpi->drop_frames_allowed) {
int64_t df_buffer_level = cpi->oxcf.drop_frames_water_mark *
(cpi->oxcf.optimal_buffer_level / 100);
if (cpi->buffer_level > df_buffer_level) {
max_boost =
((double)((cpi->buffer_level - df_buffer_level) * 2 / 3) * 16.0) /
DOUBLE_DIVIDE_CHECK((double)cpi->av_per_frame_bandwidth);
} else {
max_boost = 0.0;
}
} else if (cpi->buffer_level > 0) {
max_boost = ((double)(cpi->buffer_level * 2 / 3) * 16.0) /
DOUBLE_DIVIDE_CHECK((double)cpi->av_per_frame_bandwidth);
} else {
max_boost = 0.0;
}
if (boost_score > max_boost) boost_score = max_boost;
}
/* Dont allow conventional gf too near the next kf */
if ((cpi->twopass.frames_to_key - i) < MIN_GF_INTERVAL) {
while (i < cpi->twopass.frames_to_key) {
i++;
if (EOF == input_stats(cpi, this_frame)) break;
if (i < cpi->twopass.frames_to_key) {
mod_frame_err = calculate_modified_err(cpi, this_frame);
gf_group_err += mod_frame_err;
}
}
}
cpi->gfu_boost = (int)(boost_score * 100.0) >> 4;
#if NEW_BOOST
/* Alterrnative boost calculation for alt ref */
alt_boost = calc_arf_boost(cpi, 0, (i - 1), (i - 1), &f_boost, &b_boost);
#endif
/* Should we use the alternate refernce frame */
if (allow_alt_ref && (i >= MIN_GF_INTERVAL) &&
/* dont use ARF very near next kf */
(i <= (cpi->twopass.frames_to_key - MIN_GF_INTERVAL)) &&
#if NEW_BOOST
((next_frame.pcnt_inter > 0.75) || (next_frame.pcnt_second_ref > 0.5)) &&
((mv_in_out_accumulator / (double)i > -0.2) ||
(mv_in_out_accumulator > -2.0)) &&
(b_boost > 100) && (f_boost > 100))
#else
(next_frame.pcnt_inter > 0.75) &&
((mv_in_out_accumulator / (double)i > -0.2) ||
(mv_in_out_accumulator > -2.0)) &&
(cpi->gfu_boost > 100) && (cpi->twopass.gf_decay_rate <=
(ARF_DECAY_THRESH + (cpi->gfu_boost / 200))))
#endif
{
int Boost;
int allocation_chunks;
int Q =
(cpi->oxcf.fixed_q < 0) ? cpi->last_q[INTER_FRAME] : cpi->oxcf.fixed_q;
int tmp_q;
int arf_frame_bits = 0;
int group_bits;
#if NEW_BOOST
cpi->gfu_boost = alt_boost;
#endif
/* Estimate the bits to be allocated to the group as a whole */
if ((cpi->twopass.kf_group_bits > 0) &&
(cpi->twopass.kf_group_error_left > 0)) {
group_bits =
(int)((double)cpi->twopass.kf_group_bits *
(gf_group_err / (double)cpi->twopass.kf_group_error_left));
} else {
group_bits = 0;
}
/* Boost for arf frame */
#if NEW_BOOST
Boost = (alt_boost * GFQ_ADJUSTMENT) / 100;
#else
Boost = (cpi->gfu_boost * 3 * GFQ_ADJUSTMENT) / (2 * 100);
#endif
Boost += (i * 50);
/* Set max and minimum boost and hence minimum allocation */
if (Boost > ((cpi->baseline_gf_interval + 1) * 200)) {
Boost = ((cpi->baseline_gf_interval + 1) * 200);
} else if (Boost < 125) {
Boost = 125;
}
allocation_chunks = (i * 100) + Boost;
/* Normalize Altboost and allocations chunck down to prevent overflow */
while (Boost > 1000) {
Boost /= 2;
allocation_chunks /= 2;
}
/* Calculate the number of bits to be spent on the arf based on the
* boost number
*/
arf_frame_bits =
(int)((double)Boost * (group_bits / (double)allocation_chunks));
/* Estimate if there are enough bits available to make worthwhile use
* of an arf.
*/
tmp_q = estimate_q(cpi, mod_frame_err, (int)arf_frame_bits);
/* Only use an arf if it is likely we will be able to code
* it at a lower Q than the surrounding frames.
*/
if (tmp_q < cpi->worst_quality) {
int half_gf_int;
int frames_after_arf;
int frames_bwd = cpi->oxcf.arnr_max_frames - 1;
int frames_fwd = cpi->oxcf.arnr_max_frames - 1;
cpi->source_alt_ref_pending = 1;
/*
* For alt ref frames the error score for the end frame of the
* group (the alt ref frame) should not contribute to the group
* total and hence the number of bit allocated to the group.
* Rather it forms part of the next group (it is the GF at the
* start of the next group)
* gf_group_err -= mod_frame_err;
*
* For alt ref frames alt ref frame is technically part of the
* GF frame for the next group but we always base the error
* calculation and bit allocation on the current group of frames.
*
* Set the interval till the next gf or arf.
* For ARFs this is the number of frames to be coded before the
* future frame that is coded as an ARF.
* The future frame itself is part of the next group
*/
cpi->baseline_gf_interval = i;
/*
* Define the arnr filter width for this group of frames:
* We only filter frames that lie within a distance of half
* the GF interval from the ARF frame. We also have to trap
* cases where the filter extends beyond the end of clip.
* Note: this_frame->frame has been updated in the loop
* so it now points at the ARF frame.
*/
half_gf_int = cpi->baseline_gf_interval >> 1;
frames_after_arf =
(int)(cpi->twopass.total_stats.count - this_frame->frame - 1);
switch (cpi->oxcf.arnr_type) {
case 1: /* Backward filter */
frames_fwd = 0;
if (frames_bwd > half_gf_int) frames_bwd = half_gf_int;
break;
case 2: /* Forward filter */
if (frames_fwd > half_gf_int) frames_fwd = half_gf_int;
if (frames_fwd > frames_after_arf) frames_fwd = frames_after_arf;
frames_bwd = 0;
break;
case 3: /* Centered filter */
default:
frames_fwd >>= 1;
if (frames_fwd > frames_after_arf) frames_fwd = frames_after_arf;
if (frames_fwd > half_gf_int) frames_fwd = half_gf_int;
frames_bwd = frames_fwd;
/* For even length filter there is one more frame backward
* than forward: e.g. len=6 ==> bbbAff, len=7 ==> bbbAfff.
*/
if (frames_bwd < half_gf_int) {
frames_bwd += (cpi->oxcf.arnr_max_frames + 1) & 0x1;
}
break;
}
cpi->active_arnr_frames = frames_bwd + 1 + frames_fwd;
} else {
cpi->source_alt_ref_pending = 0;
cpi->baseline_gf_interval = i;
}
} else {
cpi->source_alt_ref_pending = 0;
cpi->baseline_gf_interval = i;
}
/*
* Now decide how many bits should be allocated to the GF group as a
* proportion of those remaining in the kf group.
* The final key frame group in the clip is treated as a special case
* where cpi->twopass.kf_group_bits is tied to cpi->twopass.bits_left.
* This is also important for short clips where there may only be one
* key frame.
*/
if (cpi->twopass.frames_to_key >=
(int)(cpi->twopass.total_stats.count - cpi->common.current_video_frame)) {
cpi->twopass.kf_group_bits =
(cpi->twopass.bits_left > 0) ? cpi->twopass.bits_left : 0;
}
/* Calculate the bits to be allocated to the group as a whole */
if ((cpi->twopass.kf_group_bits > 0) &&
(cpi->twopass.kf_group_error_left > 0)) {
cpi->twopass.gf_group_bits =
(int64_t)(cpi->twopass.kf_group_bits *
(gf_group_err / cpi->twopass.kf_group_error_left));
} else {
cpi->twopass.gf_group_bits = 0;
}
cpi->twopass.gf_group_bits =
(cpi->twopass.gf_group_bits < 0)
? 0
: (cpi->twopass.gf_group_bits > cpi->twopass.kf_group_bits)
? cpi->twopass.kf_group_bits
: cpi->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 (cpi->twopass.gf_group_bits >
(int64_t)max_bits * cpi->baseline_gf_interval) {
cpi->twopass.gf_group_bits = (int64_t)max_bits * cpi->baseline_gf_interval;
}
/* Reset the file position */
reset_fpf_position(cpi, start_pos);
/* Update the record of error used so far (only done once per gf group) */
cpi->twopass.modified_error_used += gf_group_err;
/* Assign bits to the arf or gf. */
for (i = 0; i <= (cpi->source_alt_ref_pending &&
cpi->common.frame_type != KEY_FRAME);
i++) {
int Boost;
int allocation_chunks;
int Q =
(cpi->oxcf.fixed_q < 0) ? cpi->last_q[INTER_FRAME] : cpi->oxcf.fixed_q;
int gf_bits;
/* For ARF frames */
if (cpi->source_alt_ref_pending && i == 0) {
#if NEW_BOOST
Boost = (alt_boost * GFQ_ADJUSTMENT) / 100;
#else
Boost = (cpi->gfu_boost * 3 * GFQ_ADJUSTMENT) / (2 * 100);
#endif
Boost += (cpi->baseline_gf_interval * 50);
/* Set max and minimum boost and hence minimum allocation */
if (Boost > ((cpi->baseline_gf_interval + 1) * 200)) {
Boost = ((cpi->baseline_gf_interval + 1) * 200);
} else if (Boost < 125) {
Boost = 125;
}
allocation_chunks = ((cpi->baseline_gf_interval + 1) * 100) + Boost;
}
/* Else for standard golden frames */
else {
/* boost based on inter / intra ratio of subsequent frames */
Boost = (cpi->gfu_boost * GFQ_ADJUSTMENT) / 100;
/* Set max and minimum boost and hence minimum allocation */
if (Boost > (cpi->baseline_gf_interval * 150)) {
Boost = (cpi->baseline_gf_interval * 150);
} else if (Boost < 125) {
Boost = 125;
}
allocation_chunks = (cpi->baseline_gf_interval * 100) + (Boost - 100);
}
/* Normalize Altboost and allocations chunck down to prevent overflow */
while (Boost > 1000) {
Boost /= 2;
allocation_chunks /= 2;
}
/* Calculate the number of bits to be spent on the gf or arf based on
* the boost number
*/
gf_bits = (int)((double)Boost *
(cpi->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 (mod_frame_err < gf_group_err / (double)cpi->baseline_gf_interval) {
double alt_gf_grp_bits;
int alt_gf_bits;
alt_gf_grp_bits =
(double)cpi->twopass.kf_group_bits *
(mod_frame_err * (double)cpi->baseline_gf_interval) /
DOUBLE_DIVIDE_CHECK((double)cpi->twopass.kf_group_error_left);
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
*/
else {
int alt_gf_bits =
(int)((double)cpi->twopass.kf_group_bits * mod_frame_err /
DOUBLE_DIVIDE_CHECK((double)cpi->twopass.kf_group_error_left));
if (alt_gf_bits > gf_bits) {
gf_bits = alt_gf_bits;
}
}
/* Apply an additional limit for CBR */
if (cpi->oxcf.end_usage == USAGE_STREAM_FROM_SERVER) {
if (cpi->twopass.gf_bits > (int)(cpi->buffer_level >> 1)) {
cpi->twopass.gf_bits = (int)(cpi->buffer_level >> 1);
}
}
/* Dont allow a negative value for gf_bits */
if (gf_bits < 0) gf_bits = 0;
/* Add in minimum for a frame */
gf_bits += cpi->min_frame_bandwidth;
if (i == 0) {
cpi->twopass.gf_bits = gf_bits;
}
if (i == 1 || (!cpi->source_alt_ref_pending &&
(cpi->common.frame_type != KEY_FRAME))) {
/* Per frame bit target for this frame */
cpi->per_frame_bandwidth = gf_bits;
}
}
{
/* Adjust KF group bits and error remainin */
cpi->twopass.kf_group_error_left -= (int64_t)gf_group_err;
cpi->twopass.kf_group_bits -= cpi->twopass.gf_group_bits;
if (cpi->twopass.kf_group_bits < 0) cpi->twopass.kf_group_bits = 0;
/* Note the error score left in the remaining frames of the group.
* For normal GFs we want to remove the error score for the first
* frame of the group (except in Key frame case where this has
* already happened)
*/
if (!cpi->source_alt_ref_pending && cpi->common.frame_type != KEY_FRAME) {
cpi->twopass.gf_group_error_left =
(int)(gf_group_err - gf_first_frame_err);
} else {
cpi->twopass.gf_group_error_left = (int)gf_group_err;
}
cpi->twopass.gf_group_bits -=
cpi->twopass.gf_bits - cpi->min_frame_bandwidth;
if (cpi->twopass.gf_group_bits < 0) cpi->twopass.gf_group_bits = 0;
/* This condition could fail if there are two kfs very close together
* despite (MIN_GF_INTERVAL) and would cause a devide by 0 in the
* calculation of cpi->twopass.alt_extra_bits.
*/
if (cpi->baseline_gf_interval >= 3) {
#if NEW_BOOST
int boost = (cpi->source_alt_ref_pending) ? b_boost : cpi->gfu_boost;
#else
int boost = cpi->gfu_boost;
#endif
if (boost >= 150) {
int pct_extra;
pct_extra = (boost - 100) / 50;
pct_extra = (pct_extra > 20) ? 20 : pct_extra;
cpi->twopass.alt_extra_bits =
(int)(cpi->twopass.gf_group_bits * pct_extra) / 100;
cpi->twopass.gf_group_bits -= cpi->twopass.alt_extra_bits;
cpi->twopass.alt_extra_bits /= ((cpi->baseline_gf_interval - 1) >> 1);
} else {
cpi->twopass.alt_extra_bits = 0;
}
} else {
cpi->twopass.alt_extra_bits = 0;
}
}
/* Adjustments based on a measure of complexity of the section */
if (cpi->common.frame_type != KEY_FRAME) {
FIRSTPASS_STATS sectionstats;
double Ratio;
zero_stats(§ionstats);
reset_fpf_position(cpi, start_pos);
for (i = 0; i < cpi->baseline_gf_interval; ++i) {
input_stats(cpi, &next_frame);
accumulate_stats(§ionstats, &next_frame);
}
avg_stats(§ionstats);
cpi->twopass.section_intra_rating =
(unsigned int)(sectionstats.intra_error /
DOUBLE_DIVIDE_CHECK(sectionstats.coded_error));
Ratio = sectionstats.intra_error /
DOUBLE_DIVIDE_CHECK(sectionstats.coded_error);
cpi->twopass.section_max_qfactor = 1.0 - ((Ratio - 10.0) * 0.025);
if (cpi->twopass.section_max_qfactor < 0.80) {
cpi->twopass.section_max_qfactor = 0.80;
}
reset_fpf_position(cpi, 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(VP8_COMP *cpi, FIRSTPASS_STATS *this_frame) {
int target_frame_size;
double modified_err;
double err_fraction;
int max_bits = frame_max_bits(cpi); /* Max for a single frame */
/* Calculate modified prediction error used in bit allocation */
modified_err = calculate_modified_err(cpi, this_frame);
/* What portion of the remaining GF group error is used by this frame */
if (cpi->twopass.gf_group_error_left > 0) {
err_fraction = modified_err / cpi->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)cpi->twopass.gf_group_bits * err_fraction);
/* Clip to target size to 0 - max_bits (or cpi->twopass.gf_group_bits)
* at the top end.
*/
if (target_frame_size < 0) {
target_frame_size = 0;
} else {
if (target_frame_size > max_bits) target_frame_size = max_bits;
if (target_frame_size > cpi->twopass.gf_group_bits) {
target_frame_size = (int)cpi->twopass.gf_group_bits;
}
}
/* Adjust error and bits remaining */
cpi->twopass.gf_group_error_left -= (int)modified_err;
cpi->twopass.gf_group_bits -= target_frame_size;
if (cpi->twopass.gf_group_bits < 0) cpi->twopass.gf_group_bits = 0;
/* Add in the minimum number of bits that is set aside for every frame. */
target_frame_size += cpi->min_frame_bandwidth;
/* Every other frame gets a few extra bits */
if ((cpi->frames_since_golden & 0x01) &&
(cpi->frames_till_gf_update_due > 0)) {
target_frame_size += cpi->twopass.alt_extra_bits;
}
/* Per frame bit target for this frame */
cpi->per_frame_bandwidth = target_frame_size;
}
void vp8_second_pass(VP8_COMP *cpi) {
int tmp_q;
int frames_left =
(int)(cpi->twopass.total_stats.count - cpi->common.current_video_frame);
FIRSTPASS_STATS this_frame;
FIRSTPASS_STATS this_frame_copy;
double this_frame_intra_error;
double this_frame_coded_error;
int overhead_bits;
vp8_zero(this_frame);
if (!cpi->twopass.stats_in) {
return;
}
vpx_clear_system_state();
if (EOF == input_stats(cpi, &this_frame)) return;
this_frame_intra_error = this_frame.intra_error;
this_frame_coded_error = this_frame.coded_error;
/* keyframe and section processing ! */
if (cpi->twopass.frames_to_key == 0) {
/* Define next KF group and assign bits to it */
memcpy(&this_frame_copy, &this_frame, sizeof(this_frame));
find_next_key_frame(cpi, &this_frame_copy);
/* Special case: Error error_resilient_mode mode does not make much
* sense for two pass but with its current meaning this code is
* designed to stop outlandish behaviour if someone does set it when
* using two pass. It effectively disables GF groups. This is
* temporary code until we decide what should really happen in this
* case.
*/
if (cpi->oxcf.error_resilient_mode) {
cpi->twopass.gf_group_bits = cpi->twopass.kf_group_bits;
cpi->twopass.gf_group_error_left = (int)cpi->twopass.kf_group_error_left;
cpi->baseline_gf_interval = cpi->twopass.frames_to_key;
cpi->frames_till_gf_update_due = cpi->baseline_gf_interval;
cpi->source_alt_ref_pending = 0;
}
}
/* Is this a GF / ARF (Note that a KF is always also a GF) */
if (cpi->frames_till_gf_update_due == 0) {
/* Define next gf group and assign bits to it */
memcpy(&this_frame_copy, &this_frame, sizeof(this_frame));
define_gf_group(cpi, &this_frame_copy);
/* If we are going to code an altref frame at the end of the group
* and the current frame is not a key frame.... If the previous
* group used an arf this frame has already benefited from that arf
* boost and it should not be given extra bits If the previous
* group was NOT coded using arf we may want to apply some boost to
* this GF as well
*/
if (cpi->source_alt_ref_pending && (cpi->common.frame_type != KEY_FRAME)) {
/* Assign a standard frames worth of bits from those allocated
* to the GF group
*/
int bak = cpi->per_frame_bandwidth;
memcpy(&this_frame_copy, &this_frame, sizeof(this_frame));
assign_std_frame_bits(cpi, &this_frame_copy);
cpi->per_frame_bandwidth = bak;
}
}
/* Otherwise this is an ordinary frame */
else {
/* Special case: Error error_resilient_mode mode does not make much
* sense for two pass but with its current meaning but this code is
* designed to stop outlandish behaviour if someone does set it
* when using two pass. It effectively disables GF groups. This is
* temporary code till we decide what should really happen in this
* case.
*/
if (cpi->oxcf.error_resilient_mode) {
cpi->frames_till_gf_update_due = cpi->twopass.frames_to_key;
if (cpi->common.frame_type != KEY_FRAME) {
/* Assign bits from those allocated to the GF group */
memcpy(&this_frame_copy, &this_frame, sizeof(this_frame));
assign_std_frame_bits(cpi, &this_frame_copy);
}
} else {
/* Assign bits from those allocated to the GF group */
memcpy(&this_frame_copy, &this_frame, sizeof(this_frame));
assign_std_frame_bits(cpi, &this_frame_copy);
}
}
/* Keep a globally available copy of this and the next frame's iiratio. */
cpi->twopass.this_iiratio =
(unsigned int)(this_frame_intra_error /
DOUBLE_DIVIDE_CHECK(this_frame_coded_error));
{
FIRSTPASS_STATS next_frame;
if (lookup_next_frame_stats(cpi, &next_frame) != EOF) {
cpi->twopass.next_iiratio =
(unsigned int)(next_frame.intra_error /
DOUBLE_DIVIDE_CHECK(next_frame.coded_error));
}
}
/* Set nominal per second bandwidth for this frame */
cpi->target_bandwidth =
(int)(cpi->per_frame_bandwidth * cpi->output_framerate);
if (cpi->target_bandwidth < 0) cpi->target_bandwidth = 0;
/* Account for mv, mode and other overheads. */
overhead_bits = (int)estimate_modemvcost(cpi, &cpi->twopass.total_left_stats);
/* Special case code for first frame. */
if (cpi->common.current_video_frame == 0) {
cpi->twopass.est_max_qcorrection_factor = 1.0;
/* Set a cq_level in constrained quality mode. */
if (cpi->oxcf.end_usage == USAGE_CONSTRAINED_QUALITY) {
int est_cq;
est_cq = estimate_cq(cpi, &cpi->twopass.total_left_stats,
(int)(cpi->twopass.bits_left / frames_left),
overhead_bits);
cpi->cq_target_quality = cpi->oxcf.cq_level;
if (est_cq > cpi->cq_target_quality) cpi->cq_target_quality = est_cq;
}
/* guess at maxq needed in 2nd pass */
cpi->twopass.maxq_max_limit = cpi->worst_quality;
cpi->twopass.maxq_min_limit = cpi->best_quality;
tmp_q = estimate_max_q(cpi, &cpi->twopass.total_left_stats,
(int)(cpi->twopass.bits_left / frames_left),
overhead_bits);
/* Limit the maxq value returned subsequently.
* This increases the risk of overspend or underspend if the initial
* estimate for the clip is bad, but helps prevent excessive
* variation in Q, especially near the end of a clip
* where for example a small overspend may cause Q to crash
*/
cpi->twopass.maxq_max_limit =
((tmp_q + 32) < cpi->worst_quality) ? (tmp_q + 32) : cpi->worst_quality;
cpi->twopass.maxq_min_limit =
((tmp_q - 32) > cpi->best_quality) ? (tmp_q - 32) : cpi->best_quality;
cpi->active_worst_quality = tmp_q;
cpi->ni_av_qi = tmp_q;
}
/* The last few frames of a clip almost always have to few or too many
* bits and for the sake of over exact rate control we dont want to make
* radical adjustments to the allowed quantizer range just to use up a
* few surplus bits or get beneath the target rate.
*/
else if ((cpi->common.current_video_frame <
(((unsigned int)cpi->twopass.total_stats.count * 255) >> 8)) &&
((cpi->common.current_video_frame + cpi->baseline_gf_interval) <
(unsigned int)cpi->twopass.total_stats.count)) {
if (frames_left < 1) frames_left = 1;
tmp_q = estimate_max_q(cpi, &cpi->twopass.total_left_stats,
(int)(cpi->twopass.bits_left / frames_left),
overhead_bits);
/* Move active_worst_quality but in a damped way */
if (tmp_q > cpi->active_worst_quality) {
cpi->active_worst_quality++;
} else if (tmp_q < cpi->active_worst_quality) {
cpi->active_worst_quality--;
}
cpi->active_worst_quality =
((cpi->active_worst_quality * 3) + tmp_q + 2) / 4;
}
cpi->twopass.frames_to_key--;
/* Update the total stats remaining sturcture */
subtract_stats(&cpi->twopass.total_left_stats, &this_frame);
}
static int test_candidate_kf(VP8_COMP *cpi, FIRSTPASS_STATS *last_frame,
FIRSTPASS_STATS *this_frame,
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) < .25) &&
((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) >
.40) ||
(fabs(last_frame->intra_error - this_frame->intra_error) /
DOUBLE_DIVIDE_CHECK(this_frame->intra_error) >
.40) ||
((next_frame->intra_error /
DOUBLE_DIVIDE_CHECK(next_frame->coded_error)) > 3.5))))) {
int i;
FIRSTPASS_STATS *start_pos;
FIRSTPASS_STATS local_next_frame;
double boost_score = 0.0;
double old_boost_score = 0.0;
double decay_accumulator = 1.0;
double next_iiratio;
memcpy(&local_next_frame, next_frame, sizeof(*next_frame));
/* Note the starting file position so we can reset to it */
start_pos = cpi->twopass.stats_in;
/* Examine how well the key frame predicts subsequent frames */
for (i = 0; i < 16; ++i) {
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 = decay_accumulator * local_next_frame.pcnt_inter;
} else {
decay_accumulator =
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) < 0.5) ||
(local_next_frame.intra_error < 200)) {
break;
}
old_boost_score = boost_score;
/* Get the next frame details */
if (EOF == input_stats(cpi, &local_next_frame)) break;
}
/* If there is tolerable prediction for at least the next 3 frames
* then break out else discard this pottential key frame and move on
*/
if (boost_score > 5.0 && (i > 3)) {
is_viable_kf = 1;
} else {
/* Reset the file position */
reset_fpf_position(cpi, start_pos);
is_viable_kf = 0;
}
}
return is_viable_kf;
}
static void find_next_key_frame(VP8_COMP *cpi, FIRSTPASS_STATS *this_frame) {
int i, j;
FIRSTPASS_STATS last_frame;
FIRSTPASS_STATS first_frame;
FIRSTPASS_STATS next_frame;
FIRSTPASS_STATS *start_position;
double decay_accumulator = 1.0;
double boost_score = 0;
double old_boost_score = 0.0;
double loop_decay_rate;
double kf_mod_err = 0.0;
double kf_group_err = 0.0;
double kf_group_intra_err = 0.0;
double kf_group_coded_err = 0.0;
double recent_loop_decay[8] = { 1.0, 1.0, 1.0, 1.0, 1.0, 1.0, 1.0, 1.0 };
memset(&next_frame, 0, sizeof(next_frame));
vpx_clear_system_state();
start_position = cpi->twopass.stats_in;
cpi->common.frame_type = KEY_FRAME;
/* is this a forced key frame by interval */
cpi->this_key_frame_forced = cpi->next_key_frame_forced;
/* Clear the alt ref active flag as this can never be active on a key
* frame
*/
cpi->source_alt_ref_active = 0;
/* Kf is always a gf so clear frames till next gf counter */
cpi->frames_till_gf_update_due = 0;
cpi->twopass.frames_to_key = 1;
/* Take a copy of the initial frame details */
memcpy(&first_frame, this_frame, sizeof(*this_frame));
cpi->twopass.kf_group_bits = 0;
cpi->twopass.kf_group_error_left = 0;
kf_mod_err = calculate_modified_err(cpi, this_frame);
/* find the next keyframe */
i = 0;
while (cpi->twopass.stats_in < cpi->twopass.stats_in_end) {
/* Accumulate kf group error */
kf_group_err += calculate_modified_err(cpi, this_frame);
/* These figures keep intra and coded error counts for all frames
* including key frames in the group. The effect of the key frame
* itself can be subtracted out using the first_frame data
* collected above
*/
kf_group_intra_err += this_frame->intra_error;
kf_group_coded_err += this_frame->coded_error;
/* Load the next frame's stats. */
memcpy(&last_frame, this_frame, sizeof(*this_frame));
input_stats(cpi, this_frame);
/* Provided that we are not at the end of the file... */
if (cpi->oxcf.auto_key &&
lookup_next_frame_stats(cpi, &next_frame) != EOF) {
/* Normal scene cut check */
if ((i >= MIN_GF_INTERVAL) &&
test_candidate_kf(cpi, &last_frame, this_frame, &next_frame)) {
break;
}
/* How fast is prediction quality decaying */
loop_decay_rate = get_prediction_decay_rate(cpi, &next_frame);
/* We want to know something about the recent past... rather than
* as used elsewhere where we are concened 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 = decay_accumulator * recent_loop_decay[j];
}
/* Special check for transition or high motion followed by a
* static scene.
*/
if (detect_transition_to_still(cpi, i,
((int)(cpi->key_frame_frequency) - (int)i),
loop_decay_rate, decay_accumulator)) {
break;
}
/* Step on to the next frame */
cpi->twopass.frames_to_key++;
/* If we don't have a real key frame within the next two
* forcekeyframeevery intervals then break out of the loop.
*/
if (cpi->twopass.frames_to_key >= 2 * (int)cpi->key_frame_frequency) {
break;
}
} else {
cpi->twopass.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 &&
cpi->twopass.frames_to_key > (int)cpi->key_frame_frequency) {
FIRSTPASS_STATS *current_pos = cpi->twopass.stats_in;
FIRSTPASS_STATS tmp_frame;
cpi->twopass.frames_to_key /= 2;
/* Copy first frame details */
memcpy(&tmp_frame, &first_frame, sizeof(first_frame));
/* Reset to the start of the group */
reset_fpf_position(cpi, start_position);
kf_group_err = 0;
kf_group_intra_err = 0;
kf_group_coded_err = 0;
/* Rescan to get the correct error data for the forced kf group */
for (i = 0; i < cpi->twopass.frames_to_key; ++i) {
/* Accumulate kf group errors */
kf_group_err += calculate_modified_err(cpi, &tmp_frame);
kf_group_intra_err += tmp_frame.intra_error;
kf_group_coded_err += tmp_frame.coded_error;
/* Load a the next frame's stats */
input_stats(cpi, &tmp_frame);
}
/* Reset to the start of the group */
reset_fpf_position(cpi, current_pos);
cpi->next_key_frame_forced = 1;
} else {
cpi->next_key_frame_forced = 0;
}
/* Special case for the last frame of the file */
if (cpi->twopass.stats_in >= cpi->twopass.stats_in_end) {
/* Accumulate kf group error */
kf_group_err += calculate_modified_err(cpi, this_frame);
/* These figures keep intra and coded error counts for all frames
* including key frames in the group. The effect of the key frame
* itself can be subtracted out using the first_frame data
* collected above
*/
kf_group_intra_err += this_frame->intra_error;
kf_group_coded_err += this_frame->coded_error;
}
/* Calculate the number of bits that should be assigned to the kf group. */
if ((cpi->twopass.bits_left > 0) &&
(cpi->twopass.modified_error_left > 0.0)) {
/* Max for a single normal frame (not key frame) */
int max_bits = frame_max_bits(cpi);
/* Maximum bits for the kf group */
int64_t max_grp_bits;
/* Default allocation based on bits left and relative
* complexity of the section
*/
cpi->twopass.kf_group_bits =
(int64_t)(cpi->twopass.bits_left *
(kf_group_err / cpi->twopass.modified_error_left));
/* Clip based on maximum per frame rate defined by the user. */
max_grp_bits = (int64_t)max_bits * (int64_t)cpi->twopass.frames_to_key;
if (cpi->twopass.kf_group_bits > max_grp_bits) {
cpi->twopass.kf_group_bits = max_grp_bits;
}
/* Additional special case for CBR if buffer is getting full. */
if (cpi->oxcf.end_usage == USAGE_STREAM_FROM_SERVER) {
int64_t opt_buffer_lvl = cpi->oxcf.optimal_buffer_level;
int64_t buffer_lvl = cpi->buffer_level;
/* If the buffer is near or above the optimal and this kf group is
* not being allocated much then increase the allocation a bit.
*/
if (buffer_lvl >= opt_buffer_lvl) {
int64_t high_water_mark =
(opt_buffer_lvl + cpi->oxcf.maximum_buffer_size) >> 1;
int64_t av_group_bits;
/* Av bits per frame * number of frames */
av_group_bits = (int64_t)cpi->av_per_frame_bandwidth *
(int64_t)cpi->twopass.frames_to_key;
/* We are at or above the maximum. */
if (cpi->buffer_level >= high_water_mark) {
int64_t min_group_bits;
min_group_bits =
av_group_bits + (int64_t)(buffer_lvl - high_water_mark);
if (cpi->twopass.kf_group_bits < min_group_bits) {
cpi->twopass.kf_group_bits = min_group_bits;
}
}
/* We are above optimal but below the maximum */
else if (cpi->twopass.kf_group_bits < av_group_bits) {
int64_t bits_below_av = av_group_bits - cpi->twopass.kf_group_bits;
cpi->twopass.kf_group_bits += (int64_t)(
(double)bits_below_av * (double)(buffer_lvl - opt_buffer_lvl) /
(double)(high_water_mark - opt_buffer_lvl));
}
}
}
} else {
cpi->twopass.kf_group_bits = 0;
}
/* Reset the first pass file position */
reset_fpf_position(cpi, 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;
for (i = 0; i < cpi->twopass.frames_to_key; ++i) {
double r;
if (EOF == input_stats(cpi, &next_frame)) break;
if (next_frame.intra_error > cpi->twopass.kf_intra_err_min) {
r = (IIKFACTOR2 * next_frame.intra_error /
DOUBLE_DIVIDE_CHECK(next_frame.coded_error));
} else {
r = (IIKFACTOR2 * cpi->twopass.kf_intra_err_min /
DOUBLE_DIVIDE_CHECK(next_frame.coded_error));
}
if (r > RMAX) r = RMAX;
/* How fast is prediction quality decaying */
loop_decay_rate = get_prediction_decay_rate(cpi, &next_frame);
decay_accumulator = decay_accumulator * loop_decay_rate;
decay_accumulator = decay_accumulator < 0.1 ? 0.1 : decay_accumulator;
boost_score += (decay_accumulator * r);
if ((i > MIN_GF_INTERVAL) && ((boost_score - old_boost_score) < 1.0)) {
break;
}
old_boost_score = boost_score;
}
if (1) {
FIRSTPASS_STATS sectionstats;
double Ratio;
zero_stats(§ionstats);
reset_fpf_position(cpi, start_position);
for (i = 0; i < cpi->twopass.frames_to_key; ++i) {
input_stats(cpi, &next_frame);
accumulate_stats(§ionstats, &next_frame);
}
avg_stats(§ionstats);
cpi->twopass.section_intra_rating =
(unsigned int)(sectionstats.intra_error /
DOUBLE_DIVIDE_CHECK(sectionstats.coded_error));
Ratio = sectionstats.intra_error /
DOUBLE_DIVIDE_CHECK(sectionstats.coded_error);
cpi->twopass.section_max_qfactor = 1.0 - ((Ratio - 10.0) * 0.025);
if (cpi->twopass.section_max_qfactor < 0.80) {
cpi->twopass.section_max_qfactor = 0.80;
}
}
/* When using CBR apply additional buffer fullness related upper limits */
if (cpi->oxcf.end_usage == USAGE_STREAM_FROM_SERVER) {
double max_boost;
if (cpi->drop_frames_allowed) {
int df_buffer_level = (int)(cpi->oxcf.drop_frames_water_mark *
(cpi->oxcf.optimal_buffer_level / 100));
if (cpi->buffer_level > df_buffer_level) {
max_boost =
((double)((cpi->buffer_level - df_buffer_level) * 2 / 3) * 16.0) /
DOUBLE_DIVIDE_CHECK((double)cpi->av_per_frame_bandwidth);
} else {
max_boost = 0.0;
}
} else if (cpi->buffer_level > 0) {
max_boost = ((double)(cpi->buffer_level * 2 / 3) * 16.0) /
DOUBLE_DIVIDE_CHECK((double)cpi->av_per_frame_bandwidth);
} else {
max_boost = 0.0;
}
if (boost_score > max_boost) boost_score = max_boost;
}
/* Reset the first pass file position */
reset_fpf_position(cpi, 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;
int Counter = cpi->twopass.frames_to_key;
int alt_kf_bits;
YV12_BUFFER_CONFIG *lst_yv12 = &cpi->common.yv12_fb[cpi->common.lst_fb_idx];
/* Min boost based on kf interval */
#if 0
while ((kf_boost < 48) && (Counter > 0))
{
Counter -= 2;
kf_boost ++;
}
#endif
if (kf_boost < 48) {
kf_boost += ((Counter + 1) >> 1);
if (kf_boost > 48) kf_boost = 48;
}
/* bigger frame sizes need larger kf boosts, smaller frames smaller
* boosts...
*/
if ((lst_yv12->y_width * lst_yv12->y_height) > (320 * 240)) {
kf_boost += 2 * (lst_yv12->y_width * lst_yv12->y_height) / (320 * 240);
} else if ((lst_yv12->y_width * lst_yv12->y_height) < (320 * 240)) {
kf_boost -= 4 * (320 * 240) / (lst_yv12->y_width * lst_yv12->y_height);
}
/* Min KF boost */
kf_boost = (int)((double)kf_boost * 100.0) >> 4; /* Scale 16 to 100 */
if (kf_boost < 250) kf_boost = 250;
/*
* We do three calculations for kf size.
* The first is based on the error score for the whole kf group.
* The second (optionaly) on the key frames own error if this is
* smaller than the average for the group.
* The final one insures 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 totaly static
* as measured by the decay accumulator. In this case we want to
* spend almost all of the bits on the key frame.
* cpi->twopass.frames_to_key-1 because key frame itself is taken
* care of by kf_boost.
*/
if (decay_accumulator >= 0.99) {
allocation_chunks = ((cpi->twopass.frames_to_key - 1) * 10) + kf_boost;
} else {
allocation_chunks = ((cpi->twopass.frames_to_key - 1) * 100) + kf_boost;
}
/* Normalize Altboost and allocations chunck down to prevent overflow */
while (kf_boost > 1000) {
kf_boost /= 2;
allocation_chunks /= 2;
}
cpi->twopass.kf_group_bits =
(cpi->twopass.kf_group_bits < 0) ? 0 : cpi->twopass.kf_group_bits;
/* Calculate the number of bits to be spent on the key frame */
cpi->twopass.kf_bits =
(int)((double)kf_boost *
((double)cpi->twopass.kf_group_bits / (double)allocation_chunks));
/* Apply an additional limit for CBR */
if (cpi->oxcf.end_usage == USAGE_STREAM_FROM_SERVER) {
if (cpi->twopass.kf_bits > (int)((3 * cpi->buffer_level) >> 2)) {
cpi->twopass.kf_bits = (int)((3 * cpi->buffer_level) >> 2);
}
}
/* If the key frame is actually easier than the average for the
* kf group (which does sometimes happen... eg 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 / cpi->twopass.frames_to_key) {
double alt_kf_grp_bits =
((double)cpi->twopass.bits_left *
(kf_mod_err * (double)cpi->twopass.frames_to_key) /
DOUBLE_DIVIDE_CHECK(cpi->twopass.modified_error_left));
alt_kf_bits = (int)((double)kf_boost *
(alt_kf_grp_bits / (double)allocation_chunks));
if (cpi->twopass.kf_bits > alt_kf_bits) {
cpi->twopass.kf_bits = alt_kf_bits;
}
}
/* 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
*/
else {
alt_kf_bits = (int)((double)cpi->twopass.bits_left *
(kf_mod_err / DOUBLE_DIVIDE_CHECK(
cpi->twopass.modified_error_left)));
if (alt_kf_bits > cpi->twopass.kf_bits) {
cpi->twopass.kf_bits = alt_kf_bits;
}
}
cpi->twopass.kf_group_bits -= cpi->twopass.kf_bits;
/* Add in the minimum frame allowance */
cpi->twopass.kf_bits += cpi->min_frame_bandwidth;
/* Peer frame bit target for this frame */
cpi->per_frame_bandwidth = cpi->twopass.kf_bits;
/* Convert to a per second bitrate */
cpi->target_bandwidth = (int)(cpi->twopass.kf_bits * cpi->output_framerate);
}
/* Note the total error score of the kf group minus the key frame itself */
cpi->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
*/
cpi->twopass.modified_error_left -= kf_group_err;
if (cpi->oxcf.allow_spatial_resampling) {
int resample_trigger = 0;
int last_kf_resampled = 0;
int kf_q;
int scale_val = 0;
int hr, hs, vr, vs;
int new_width = cpi->oxcf.Width;
int new_height = cpi->oxcf.Height;
int projected_buffer_level;
int tmp_q;
double projected_bits_perframe;
double group_iiratio = (kf_group_intra_err - first_frame.intra_error) /
(kf_group_coded_err - first_frame.coded_error);
double err_per_frame = kf_group_err / cpi->twopass.frames_to_key;
double bits_per_frame;
double av_bits_per_frame;
double effective_size_ratio;
if ((cpi->common.Width != cpi->oxcf.Width) ||
(cpi->common.Height != cpi->oxcf.Height)) {
last_kf_resampled = 1;
}
/* Set back to unscaled by defaults */
cpi->common.horiz_scale = NORMAL;
cpi->common.vert_scale = NORMAL;
/* Calculate Average bits per frame. */
av_bits_per_frame = cpi->oxcf.target_bandwidth /
DOUBLE_DIVIDE_CHECK((double)cpi->framerate);
/* CBR... Use the clip average as the target for deciding resample */
if (cpi->oxcf.end_usage == USAGE_STREAM_FROM_SERVER) {
bits_per_frame = av_bits_per_frame;
}
/* In VBR we want to avoid downsampling in easy section unless we
* are under extreme pressure So use the larger of target bitrate
* for this section or average bitrate for sequence
*/
else {
/* This accounts for how hard the section is... */
bits_per_frame =
(double)(cpi->twopass.kf_group_bits / cpi->twopass.frames_to_key);
/* Dont turn to resampling in easy sections just because they
* have been assigned a small number of bits
*/
if (bits_per_frame < av_bits_per_frame) {
bits_per_frame = av_bits_per_frame;
}
}
/* bits_per_frame should comply with our minimum */
if (bits_per_frame < (cpi->oxcf.target_bandwidth *
cpi->oxcf.two_pass_vbrmin_section / 100)) {
bits_per_frame = (cpi->oxcf.target_bandwidth *
cpi->oxcf.two_pass_vbrmin_section / 100);
}
/* Work out if spatial resampling is necessary */
kf_q = estimate_kf_group_q(cpi, err_per_frame, (int)bits_per_frame,
group_iiratio);
/* If we project a required Q higher than the maximum allowed Q then
* make a guess at the actual size of frames in this section
*/
projected_bits_perframe = bits_per_frame;
tmp_q = kf_q;
while (tmp_q > cpi->worst_quality) {
projected_bits_perframe *= 1.04;
tmp_q--;
}
/* Guess at buffer level at the end of the section */
projected_buffer_level =
(int)(cpi->buffer_level -
(int)((projected_bits_perframe - av_bits_per_frame) *
cpi->twopass.frames_to_key));
if (0) {
FILE *f = fopen("Subsamle.stt", "a");
fprintf(f, " %8d %8d %8d %8d %12.0f %8d %8d %8d\n",
cpi->common.current_video_frame, kf_q, cpi->common.horiz_scale,
cpi->common.vert_scale, kf_group_err / cpi->twopass.frames_to_key,
(int)(cpi->twopass.kf_group_bits / cpi->twopass.frames_to_key),
new_height, new_width);
fclose(f);
}
/* The trigger for spatial resampling depends on the various
* parameters such as whether we are streaming (CBR) or VBR.
*/
if (cpi->oxcf.end_usage == USAGE_STREAM_FROM_SERVER) {
/* Trigger resample if we are projected to fall below down
* sample level or resampled last time and are projected to
* remain below the up sample level
*/
if ((projected_buffer_level < (cpi->oxcf.resample_down_water_mark *
cpi->oxcf.optimal_buffer_level / 100)) ||
(last_kf_resampled &&
(projected_buffer_level < (cpi->oxcf.resample_up_water_mark *
cpi->oxcf.optimal_buffer_level / 100)))) {
resample_trigger = 1;
} else {
resample_trigger = 0;
}
} else {
int64_t clip_bits = (int64_t)(
cpi->twopass.total_stats.count * cpi->oxcf.target_bandwidth /
DOUBLE_DIVIDE_CHECK((double)cpi->framerate));
int64_t over_spend = cpi->oxcf.starting_buffer_level - cpi->buffer_level;
/* If triggered last time the threshold for triggering again is
* reduced:
*
* Projected Q higher than allowed and Overspend > 5% of total
* bits
*/
if ((last_kf_resampled && (kf_q > cpi->worst_quality)) ||
((kf_q > cpi->worst_quality) && (over_spend > clip_bits / 20))) {
resample_trigger = 1;
} else {
resample_trigger = 0;
}
}
if (resample_trigger) {
while ((kf_q >= cpi->worst_quality) && (scale_val < 6)) {
scale_val++;
cpi->common.vert_scale = vscale_lookup[scale_val];
cpi->common.horiz_scale = hscale_lookup[scale_val];
Scale2Ratio(cpi->common.horiz_scale, &hr, &hs);
Scale2Ratio(cpi->common.vert_scale, &vr, &vs);
new_width = ((hs - 1) + (cpi->oxcf.Width * hr)) / hs;
new_height = ((vs - 1) + (cpi->oxcf.Height * vr)) / vs;
/* Reducing the area to 1/4 does not reduce the complexity
* (err_per_frame) to 1/4... effective_sizeratio attempts
* to provide a crude correction for this
*/
effective_size_ratio = (double)(new_width * new_height) /
(double)(cpi->oxcf.Width * cpi->oxcf.Height);
effective_size_ratio = (1.0 + (3.0 * effective_size_ratio)) / 4.0;
/* Now try again and see what Q we get with the smaller
* image size
*/
kf_q = estimate_kf_group_q(cpi, err_per_frame * effective_size_ratio,
(int)bits_per_frame, group_iiratio);
if (0) {
FILE *f = fopen("Subsamle.stt", "a");
fprintf(
f, "******** %8d %8d %8d %12.0f %8d %8d %8d\n", kf_q,
cpi->common.horiz_scale, cpi->common.vert_scale,
kf_group_err / cpi->twopass.frames_to_key,
(int)(cpi->twopass.kf_group_bits / cpi->twopass.frames_to_key),
new_height, new_width);
fclose(f);
}
}
}
if ((cpi->common.Width != new_width) ||
(cpi->common.Height != new_height)) {
cpi->common.Width = new_width;
cpi->common.Height = new_height;
vp8_alloc_compressor_data(cpi);
}
}
}