The Tor Browser: comparison media/libvpx/vp9/encoder/vp9

--1:000000000000
+:cf802a3fd841
+/*
+*  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 "vp9/encoder/vp9_block.h"
+#include "vp9/encoder/vp9_onyx_int.h"
+#include "vp9/encoder/vp9_variance.h"
+#include "vp9/encoder/vp9_encodeintra.h"
+#include "vp9/encoder/vp9_mcomp.h"
+#include "vp9/encoder/vp9_firstpass.h"
+#include "vpx_scale/vpx_scale.h"
+#include "vp9/encoder/vp9_encodeframe.h"
+#include "vp9/encoder/vp9_encodemb.h"
+#include "vp9/common/vp9_extend.h"
+#include "vp9/common/vp9_systemdependent.h"
+#include "vpx_mem/vpx_mem.h"
+#include "vpx_scale/yv12config.h"
+#include "vp9/encoder/vp9_quantize.h"
+#include "vp9/encoder/vp9_rdopt.h"
+#include "vp9/encoder/vp9_ratectrl.h"
+#include "vp9/common/vp9_quant_common.h"
+#include "vp9/common/vp9_entropymv.h"
+#include "vp9/encoder/vp9_encodemv.h"
+#include "vp9/encoder/vp9_vaq.h"
+#include "./vpx_scale_rtcd.h"
+// TODO(jkoleszar): for setup_dst_planes
+#include "vp9/common/vp9_reconinter.h"
+#define OUTPUT_FPF 0
+#define IIFACTOR   12.5
+#define IIKFACTOR1 12.5
+#define IIKFACTOR2 15.0
+#define RMAX       512.0
+#define GF_RMAX    96.0
+#define ERR_DIVISOR   150.0
+#define MIN_DECAY_FACTOR 0.1
+#define KF_MB_INTRA_MIN 150
+#define GF_MB_INTRA_MIN 100
+#define DOUBLE_DIVIDE_CHECK(x) ((x) < 0 ? (x) - 0.000001 : (x) + 0.000001)
+#define POW1 (double)cpi->oxcf.two_pass_vbrbias/100.0
+#define POW2 (double)cpi->oxcf.two_pass_vbrbias/100.0
+static void swap_yv12(YV12_BUFFER_CONFIG *a, YV12_BUFFER_CONFIG *b) {
+YV12_BUFFER_CONFIG temp = *a;
+*a = *b;
+*b = temp;
+}
+static void find_next_key_frame(VP9_COMP *cpi, FIRSTPASS_STATS *this_frame);
+static int select_cq_level(int qindex) {
+int ret_val = QINDEX_RANGE - 1;
+int i;
+double target_q = (vp9_convert_qindex_to_q(qindex) * 0.5847) + 1.0;
+for (i = 0; i < QINDEX_RANGE; i++) {
+if (target_q <= vp9_convert_qindex_to_q(i)) {
+ret_val = i;
+break;
+}
+}
+return ret_val;
+}
+// Resets the first pass file to the given position using a relative seek from
+// the current position.
+static void reset_fpf_position(VP9_COMP *cpi, FIRSTPASS_STATS *position) {
+cpi->twopass.stats_in = position;
+}
+static int lookup_next_frame_stats(VP9_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(VP9_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(VP9_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 VP9_COMP            *cpi,
+struct vpx_codec_pkt_list *pktlist,
+FIRSTPASS_STATS            *stats) {
+struct vpx_codec_cx_pkt pkt;
+pkt.kind = VPX_CODEC_STATS_PKT;
+pkt.data.twopass_stats.buf = stats;
+pkt.data.twopass_stats.sz = sizeof(FIRSTPASS_STATS);
+vpx_codec_pkt_list_add(pktlist, &pkt);
+// TEMP debug code
+#if OUTPUT_FPF
+{
+FILE *fpfile;
+fpfile = fopen("firstpass.stt", "a");
+fprintf(stdout, "%12.0f %12.0f %12.0f %12.0f %12.0f %12.4f %12.4f"
+"%12.4f %12.4f %12.4f %12.4f %12.4f %12.4f %12.4f"
+"%12.0f %12.0f %12.4f %12.0f %12.0f %12.4f\n",
+stats->frame,
+stats->intra_error,
+stats->coded_error,
+stats->sr_coded_error,
+stats->ssim_weighted_pred_err,
+stats->pcnt_inter,
+stats->pcnt_motion,
+stats->pcnt_second_ref,
+stats->pcnt_neutral,
+stats->MVr,
+stats->mvr_abs,
+stats->MVc,
+stats->mvc_abs,
+stats->MVrv,
+stats->MVcv,
+stats->mv_in_out_count,
+stats->new_mv_count,
+stats->count,
+stats->duration);
+fclose(fpfile);
+}
+#endif
+}
+static void zero_stats(FIRSTPASS_STATS *section) {
+section->frame      = 0.0;
+section->intra_error = 0.0;
+section->coded_error = 0.0;
+section->sr_coded_error = 0.0;
+section->ssim_weighted_pred_err = 0.0;
+section->pcnt_inter  = 0.0;
+section->pcnt_motion  = 0.0;
+section->pcnt_second_ref = 0.0;
+section->pcnt_neutral = 0.0;
+section->MVr        = 0.0;
+section->mvr_abs     = 0.0;
+section->MVc        = 0.0;
+section->mvc_abs     = 0.0;
+section->MVrv       = 0.0;
+section->MVcv       = 0.0;
+section->mv_in_out_count  = 0.0;
+section->new_mv_count = 0.0;
+section->count      = 0.0;
+section->duration   = 1.0;
+}
+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->sr_coded_error += frame->sr_coded_error;
+section->ssim_weighted_pred_err += frame->ssim_weighted_pred_err;
+section->pcnt_inter  += frame->pcnt_inter;
+section->pcnt_motion += frame->pcnt_motion;
+section->pcnt_second_ref += frame->pcnt_second_ref;
+section->pcnt_neutral += frame->pcnt_neutral;
+section->MVr        += frame->MVr;
+section->mvr_abs     += frame->mvr_abs;
+section->MVc        += frame->MVc;
+section->mvc_abs     += frame->mvc_abs;
+section->MVrv       += frame->MVrv;
+section->MVcv       += frame->MVcv;
+section->mv_in_out_count  += frame->mv_in_out_count;
+section->new_mv_count += frame->new_mv_count;
+section->count      += frame->count;
+section->duration   += frame->duration;
+}
+static void subtract_stats(FIRSTPASS_STATS *section, FIRSTPASS_STATS *frame) {
+section->frame -= frame->frame;
+section->intra_error -= frame->intra_error;
+section->coded_error -= frame->coded_error;
+section->sr_coded_error -= frame->sr_coded_error;
+section->ssim_weighted_pred_err -= frame->ssim_weighted_pred_err;
+section->pcnt_inter  -= frame->pcnt_inter;
+section->pcnt_motion -= frame->pcnt_motion;
+section->pcnt_second_ref -= frame->pcnt_second_ref;
+section->pcnt_neutral -= frame->pcnt_neutral;
+section->MVr        -= frame->MVr;
+section->mvr_abs     -= frame->mvr_abs;
+section->MVc        -= frame->MVc;
+section->mvc_abs     -= frame->mvc_abs;
+section->MVrv       -= frame->MVrv;
+section->MVcv       -= frame->MVcv;
+section->mv_in_out_count  -= frame->mv_in_out_count;
+section->new_mv_count -= frame->new_mv_count;
+section->count      -= frame->count;
+section->duration   -= frame->duration;
+}
+static void avg_stats(FIRSTPASS_STATS *section) {
+if (section->count < 1.0)
+return;
+section->intra_error /= section->count;
+section->coded_error /= section->count;
+section->sr_coded_error /= section->count;
+section->ssim_weighted_pred_err /= section->count;
+section->pcnt_inter  /= section->count;
+section->pcnt_second_ref /= section->count;
+section->pcnt_neutral /= section->count;
+section->pcnt_motion /= section->count;
+section->MVr        /= section->count;
+section->mvr_abs     /= section->count;
+section->MVc        /= section->count;
+section->mvc_abs     /= section->count;
+section->MVrv       /= section->count;
+section->MVcv       /= section->count;
+section->mv_in_out_count   /= section->count;
+section->duration   /= section->count;
+}
+// Calculate a modified Error used in distributing bits between easier and
+// harder frames.
+static double calculate_modified_err(VP9_COMP *cpi,
+FIRSTPASS_STATS *this_frame) {
+const FIRSTPASS_STATS *const stats = &cpi->twopass.total_stats;
+const double av_err = stats->ssim_weighted_pred_err / stats->count;
+const double this_err = this_frame->ssim_weighted_pred_err;
+return av_err * pow(this_err / DOUBLE_DIVIDE_CHECK(av_err),
+this_err > av_err ? POW1 : POW2);
+}
+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;
+uint8_t *src = source->y_buffer;
+double sum_weights = 0.0;
+// Loop through the Y plane 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(VP9_COMP *cpi) {
+// Max allocation for a single frame based on the max section guidelines
+// passed in and how many bits are left.
+// For VBR base this on the bits and frames left plus the
+// two_pass_vbrmax_section rate passed in by the user.
+const double max_bits = (1.0 * cpi->twopass.bits_left /
+(cpi->twopass.total_stats.count - cpi->common.current_video_frame)) *
+(cpi->oxcf.two_pass_vbrmax_section / 100.0);
+// Trap case where we are out of bits.
+return MAX((int)max_bits, 0);
+}
+void vp9_init_first_pass(VP9_COMP *cpi) {
+zero_stats(&cpi->twopass.total_stats);
+}
+void vp9_end_first_pass(VP9_COMP *cpi) {
+output_stats(cpi, cpi->output_pkt_list, &cpi->twopass.total_stats);
+}
+static void zz_motion_search(VP9_COMP *cpi, MACROBLOCK *x,
+YV12_BUFFER_CONFIG *recon_buffer,
+int *best_motion_err, int recon_yoffset) {
+MACROBLOCKD *const xd = &x->e_mbd;
+// Set up pointers for this macro block recon buffer
+xd->plane[0].pre[0].buf = recon_buffer->y_buffer + recon_yoffset;
+switch (xd->mi_8x8[0]->mbmi.sb_type) {
+case BLOCK_8X8:
+vp9_mse8x8(x->plane[0].src.buf, x->plane[0].src.stride,
+xd->plane[0].pre[0].buf, xd->plane[0].pre[0].stride,
+(unsigned int *)(best_motion_err));
+break;
+case BLOCK_16X8:
+vp9_mse16x8(x->plane[0].src.buf, x->plane[0].src.stride,
+xd->plane[0].pre[0].buf, xd->plane[0].pre[0].stride,
+(unsigned int *)(best_motion_err));
+break;
+case BLOCK_8X16:
+vp9_mse8x16(x->plane[0].src.buf, x->plane[0].src.stride,
+xd->plane[0].pre[0].buf, xd->plane[0].pre[0].stride,
+(unsigned int *)(best_motion_err));
+break;
+default:
+vp9_mse16x16(x->plane[0].src.buf, x->plane[0].src.stride,
+xd->plane[0].pre[0].buf, xd->plane[0].pre[0].stride,
+(unsigned int *)(best_motion_err));
+break;
+}
+}
+static void first_pass_motion_search(VP9_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;
+int num00;
+int_mv tmp_mv;
+int_mv ref_mv_full;
+int tmp_err;
+int step_param = 3;
+int further_steps = (MAX_MVSEARCH_STEPS - 1) - step_param;
+int n;
+vp9_variance_fn_ptr_t v_fn_ptr =
+cpi->fn_ptr[xd->mi_8x8[0]->mbmi.sb_type];
+int new_mv_mode_penalty = 256;
+int sr = 0;
+int quart_frm = MIN(cpi->common.width, cpi->common.height);
+// refine the motion search range accroding to the frame dimension
+// for first pass test
+while ((quart_frm << sr) < MAX_FULL_PEL_VAL)
+sr++;
+if (sr)
+sr--;
+step_param    += sr;
+further_steps -= sr;
+// override the default variance function to use MSE
+switch (xd->mi_8x8[0]->mbmi.sb_type) {
+case BLOCK_8X8:
+v_fn_ptr.vf = vp9_mse8x8;
+break;
+case BLOCK_16X8:
+v_fn_ptr.vf = vp9_mse16x8;
+break;
+case BLOCK_8X16:
+v_fn_ptr.vf = vp9_mse8x16;
+break;
+default:
+v_fn_ptr.vf = vp9_mse16x16;
+break;
+}
+// Set up pointers for this macro block recon buffer
+xd->plane[0].pre[0].buf = 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, &ref_mv_full, &tmp_mv, step_param,
+x->sadperbit16, &num00, &v_fn_ptr,
+x->nmvjointcost,
+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, &ref_mv_full, &tmp_mv,
+step_param + n, x->sadperbit16,
+&num00, &v_fn_ptr,
+x->nmvjointcost,
+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 vp9_first_pass(VP9_COMP *cpi) {
+int mb_row, mb_col;
+MACROBLOCK *const x = &cpi->mb;
+VP9_COMMON *const cm = &cpi->common;
+MACROBLOCKD *const xd = &x->e_mbd;
+TileInfo tile;
+struct macroblock_plane *const p = x->plane;
+struct macroblockd_plane *const pd = xd->plane;
+PICK_MODE_CONTEXT *ctx = &x->sb64_context;
+int i;
+int recon_yoffset, recon_uvoffset;
+const int lst_yv12_idx = cm->ref_frame_map[cpi->lst_fb_idx];
+const int gld_yv12_idx = cm->ref_frame_map[cpi->gld_fb_idx];
+YV12_BUFFER_CONFIG *const lst_yv12 = &cm->yv12_fb[lst_yv12_idx];
+YV12_BUFFER_CONFIG *const gld_yv12 = &cm->yv12_fb[gld_yv12_idx];
+YV12_BUFFER_CONFIG *const new_yv12 = get_frame_new_buffer(cm);
+const int recon_y_stride = lst_yv12->y_stride;
+const int recon_uv_stride = lst_yv12->uv_stride;
+int64_t intra_error = 0;
+int64_t coded_error = 0;
+int64_t sr_coded_error = 0;
+int sum_mvr = 0, sum_mvc = 0;
+int sum_mvr_abs = 0, sum_mvc_abs = 0;
+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;
+vp9_clear_system_state();  // __asm emms;
+vp9_setup_src_planes(x, cpi->Source, 0, 0);
+setup_pre_planes(xd, 0, lst_yv12, 0, 0, NULL);
+setup_dst_planes(xd, new_yv12, 0, 0);
+xd->mi_8x8 = cm->mi_grid_visible;
+// required for vp9_frame_init_quantizer
+xd->mi_8x8[0] = cm->mi;
+setup_block_dptrs(&x->e_mbd, cm->subsampling_x, cm->subsampling_y);
+vp9_frame_init_quantizer(cpi);
+for (i = 0; i < MAX_MB_PLANE; ++i) {
+p[i].coeff = ctx->coeff_pbuf[i][1];
+pd[i].qcoeff = ctx->qcoeff_pbuf[i][1];
+pd[i].dqcoeff = ctx->dqcoeff_pbuf[i][1];
+pd[i].eobs = ctx->eobs_pbuf[i][1];
+}
+x->skip_recode = 0;
+// Initialise the MV cost table to the defaults
+// if( cm->current_video_frame == 0)
+// if ( 0 )
+{
+vp9_init_mv_probs(cm);
+vp9_initialize_rd_consts(cpi);
+}
+// tiling is ignored in the first pass
+vp9_tile_init(&tile, cm, 0, 0);
+// for 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) + BORDER_MV_PIXELS_B16);
+x->mv_row_max = ((cm->mb_rows - 1 - mb_row) * 16)
++ BORDER_MV_PIXELS_B16;
+// 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);
+double error_weight;
+vp9_clear_system_state();  // __asm emms;
+error_weight = 1.0;  // avoid uninitialized warnings
+xd->plane[0].dst.buf = new_yv12->y_buffer + recon_yoffset;
+xd->plane[1].dst.buf = new_yv12->u_buffer + recon_uvoffset;
+xd->plane[2].dst.buf = new_yv12->v_buffer + recon_uvoffset;
+xd->left_available = (mb_col != 0);
+if (mb_col * 2 + 1 < cm->mi_cols) {
+if (mb_row * 2 + 1 < cm->mi_rows) {
+xd->mi_8x8[0]->mbmi.sb_type = BLOCK_16X16;
+} else {
+xd->mi_8x8[0]->mbmi.sb_type = BLOCK_16X8;
+}
+} else {
+if (mb_row * 2 + 1 < cm->mi_rows) {
+xd->mi_8x8[0]->mbmi.sb_type = BLOCK_8X16;
+} else {
+xd->mi_8x8[0]->mbmi.sb_type = BLOCK_8X8;
+}
+}
+xd->mi_8x8[0]->mbmi.ref_frame[0] = INTRA_FRAME;
+set_mi_row_col(xd, &tile,
+mb_row << 1,
+num_8x8_blocks_high_lookup[xd->mi_8x8[0]->mbmi.sb_type],
+mb_col << 1,
+num_8x8_blocks_wide_lookup[xd->mi_8x8[0]->mbmi.sb_type],
+cm->mi_rows, cm->mi_cols);
+if (cpi->oxcf.aq_mode == VARIANCE_AQ) {
+int energy = vp9_block_energy(cpi, x, xd->mi_8x8[0]->mbmi.sb_type);
+error_weight = vp9_vaq_inv_q_ratio(energy);
+}
+// do intra 16x16 prediction
+this_error = vp9_encode_intra(x, use_dc_pred);
+if (cpi->oxcf.aq_mode == VARIANCE_AQ) {
+vp9_clear_system_state();  // __asm emms;
+this_error *= error_weight;
+}
+// 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 for the mv.
+// When the error score is very low this causes us to pick all or lots of
+// INTRA modes and throw lots of key frames.
+// This penalty adds a cost matching that of a 0,0 mv to the intra case.
+this_error += intrapenalty;
+// 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) + BORDER_MV_PIXELS_B16);
+x->mv_col_max = ((cm->mb_cols - 1 - mb_col) * 16)
++ BORDER_MV_PIXELS_B16;
+// Other than for the first frame do a motion search
+if (cm->current_video_frame > 0) {
+int tmp_err;
+int motion_error = INT_MAX;
+int_mv mv, tmp_mv;
+// Simple 0,0 motion with no mv overhead
+zz_motion_search(cpi, x, lst_yv12, &motion_error, recon_yoffset);
+mv.as_int = tmp_mv.as_int = 0;
+// Test last reference frame using the previous best mv as the
+// starting point (best reference) for the search
+first_pass_motion_search(cpi, x, &best_ref_mv,
+&mv.as_mv, lst_yv12,
+&motion_error, recon_yoffset);
+if (cpi->oxcf.aq_mode == VARIANCE_AQ) {
+vp9_clear_system_state();  // __asm emms;
+motion_error *= error_weight;
+}
+// If the current best reference mv is not centered on 0,0 then do a 0,0
+// based search as well.
+if (best_ref_mv.as_int) {
+tmp_err = INT_MAX;
+first_pass_motion_search(cpi, x, &zero_ref_mv, &tmp_mv.as_mv,
+lst_yv12, &tmp_err, recon_yoffset);
+if (cpi->oxcf.aq_mode == VARIANCE_AQ) {
+vp9_clear_system_state();  // __asm emms;
+tmp_err *= error_weight;
+}
+if (tmp_err < motion_error) {
+motion_error = tmp_err;
+mv.as_int = tmp_mv.as_int;
+}
+}
+// Experimental search in an older reference frame
+if (cm->current_video_frame > 1) {
+// Simple 0,0 motion with no mv overhead
+zz_motion_search(cpi, x, gld_yv12,
+&gf_motion_error, recon_yoffset);
+first_pass_motion_search(cpi, x, &zero_ref_mv,
+&tmp_mv.as_mv, gld_yv12,
+&gf_motion_error, recon_yoffset);
+if (cpi->oxcf.aq_mode == VARIANCE_AQ) {
+vp9_clear_system_state();  // __asm emms;
+gf_motion_error *= error_weight;
+}
+if ((gf_motion_error < motion_error) &&
+(gf_motion_error < this_error)) {
+second_ref_count++;
+}
+// Reset to last frame as reference buffer
+xd->plane[0].pre[0].buf = lst_yv12->y_buffer + recon_yoffset;
+xd->plane[1].pre[0].buf = lst_yv12->u_buffer + recon_uvoffset;
+xd->plane[2].pre[0].buf = lst_yv12->v_buffer + recon_uvoffset;
+// In accumulating a score for the older reference frame
+// take the best of the motion predicted score and
+// the intra coded error (just as will be done for)
+// accumulation of "coded_error" for the last frame.
+if (gf_motion_error < this_error)
+sr_coded_error += gf_motion_error;
+else
+sr_coded_error += this_error;
+} else {
+sr_coded_error += motion_error;
+}
+/* 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++;
+}
+mv.as_mv.row *= 8;
+mv.as_mv.col *= 8;
+this_error = motion_error;
+vp9_set_mbmode_and_mvs(x, NEWMV, &mv);
+xd->mi_8x8[0]->mbmi.tx_size = TX_4X4;
+xd->mi_8x8[0]->mbmi.ref_frame[0] = LAST_FRAME;
+xd->mi_8x8[0]->mbmi.ref_frame[1] = NONE;
+vp9_build_inter_predictors_sby(xd, mb_row << 1,
+mb_col << 1,
+xd->mi_8x8[0]->mbmi.sb_type);
+vp9_encode_sby(x, xd->mi_8x8[0]->mbmi.sb_type);
+sum_mvr += mv.as_mv.row;
+sum_mvr_abs += abs(mv.as_mv.row);
+sum_mvc += mv.as_mv.col;
+sum_mvc_abs += abs(mv.as_mv.col);
+sum_mvrs += mv.as_mv.row * mv.as_mv.row;
+sum_mvcs += mv.as_mv.col * mv.as_mv.col;
+intercount++;
+best_ref_mv.as_int = mv.as_int;
+// Was the vector non-zero
+if (mv.as_int) {
+mvcount++;
+// Was it different from the last non zero vector
+if (mv.as_int != lastmv_as_int)
+new_mv_count++;
+lastmv_as_int = mv.as_int;
+// Does the Row vector point inwards or outwards
+if (mb_row < cm->mb_rows / 2) {
+if (mv.as_mv.row > 0)
+sum_in_vectors--;
+else if (mv.as_mv.row < 0)
+sum_in_vectors++;
+} else if (mb_row > cm->mb_rows / 2) {
+if (mv.as_mv.row > 0)
+sum_in_vectors++;
+else if (mv.as_mv.row < 0)
+sum_in_vectors--;
+}
+// Does the Row vector point inwards or outwards
+if (mb_col < cm->mb_cols / 2) {
+if (mv.as_mv.col > 0)
+sum_in_vectors--;
+else if (mv.as_mv.col < 0)
+sum_in_vectors++;
+} else if (mb_col > cm->mb_cols / 2) {
+if (mv.as_mv.col > 0)
+sum_in_vectors++;
+else if (mv.as_mv.col < 0)
+sum_in_vectors--;
+}
+}
+}
+} else {
+sr_coded_error += (int64_t)this_error;
+}
+coded_error += (int64_t)this_error;
+// adjust to the next column of macroblocks
+x->plane[0].src.buf += 16;
+x->plane[1].src.buf += 8;
+x->plane[2].src.buf += 8;
+recon_yoffset += 16;
+recon_uvoffset += 8;
+}
+// adjust to the next row of mbs
+x->plane[0].src.buf += 16 * x->plane[0].src.stride - 16 * cm->mb_cols;
+x->plane[1].src.buf += 8 * x->plane[1].src.stride - 8 * cm->mb_cols;
+x->plane[2].src.buf += 8 * x->plane[1].src.stride - 8 * cm->mb_cols;
+vp9_clear_system_state();  // __asm emms;
+}
+vp9_clear_system_state();  // __asm emms;
+{
+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);
+fps.sr_coded_error = (double)(sr_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(paulwilkins):  Handle the case when duration is set to 0, or
+// something less than the full time between subsequent values of
+// cpi->source_time_stamp.
+fps.duration = (double)(cpi->source->ts_end
+- cpi->source->ts_start);
+// don't want to do output stats with a stack variable!
+cpi->twopass.this_frame_stats = fps;
+output_stats(cpi, cpi->output_pkt_list, &cpi->twopass.this_frame_stats);
+accumulate_stats(&cpi->twopass.total_stats, &fps);
+}
+// Copy the previous Last Frame back into gf and and arf buffers if
+// the prediction is good enough... but also dont allow it to lag too far
+if ((cpi->twopass.sr_update_lag > 3) ||
+((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);
+cpi->twopass.sr_update_lag = 1;
+} else {
+cpi->twopass.sr_update_lag++;
+}
+// swap frame pointers so last frame refers to the frame we just compressed
+swap_yv12(lst_yv12, new_yv12);
+vp9_extend_frame_borders(lst_yv12, cm->subsampling_x, cm->subsampling_y);
+// 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;
+snprintf(filename, sizeof(filename), "enc%04d.yuv",
+(int)cm->current_video_frame);
+if (cm->current_video_frame == 0)
+recon_file = fopen(filename, "wb");
+else
+recon_file = fopen(filename, "ab");
+(void)fwrite(lst_yv12->buffer_alloc, lst_yv12->frame_size, 1, recon_file);
+fclose(recon_file);
+}
+cm->current_video_frame++;
+}
+// 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) {
+return -(log(prob) / log(2.0));
+}
+static int64_t estimate_modemvcost(VP9_COMP *cpi,
+FIRSTPASS_STATS *fpstats) {
+#if 0
+int mv_cost;
+int 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 vp9_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 vp9_bits_per_mb
+mode_cost =
+(int)((((av_pct_inter - av_pct_motion) * zz_cost) +
+(av_pct_motion * motion_cost) +
+(av_intra * intra_cost)) * cpi->common.MBs) << 9;
+// return mv_cost + mode_cost;
+// TODO(paulwilkins): Fix overhead costs for extended Q range.
+#endif
+return 0;
+}
+static double calc_correction_factor(double err_per_mb,
+double err_divisor,
+double pt_low,
+double pt_high,
+int q) {
+const double error_term = err_per_mb / err_divisor;
+// Adjustment based on actual quantizer to power term.
+const double power_term = MIN(vp9_convert_qindex_to_q(q) * 0.01 + pt_low,
+pt_high);
+// Calculate correction factor
+if (power_term < 1.0)
+assert(error_term >= 0.0);
+return fclamp(pow(error_term, power_term), 0.05, 5.0);
+}
+// Given a current maxQ value sets a range for future values.
+// PGW TODO..
+// This code removes direct dependency on QIndex to determine the range
+// (now uses the actual quantizer) but has not been tuned.
+static void adjust_maxq_qrange(VP9_COMP *cpi) {
+int i;
+// Set the max corresponding to cpi->avg_q * 2.0
+double q = cpi->avg_q * 2.0;
+cpi->twopass.maxq_max_limit = cpi->worst_quality;
+for (i = cpi->best_quality; i <= cpi->worst_quality; i++) {
+cpi->twopass.maxq_max_limit = i;
+if (vp9_convert_qindex_to_q(i) >= q)
+break;
+}
+// Set the min corresponding to cpi->avg_q * 0.5
+q = cpi->avg_q * 0.5;
+cpi->twopass.maxq_min_limit = cpi->best_quality;
+for (i = cpi->worst_quality; i >= cpi->best_quality; i--) {
+cpi->twopass.maxq_min_limit = i;
+if (vp9_convert_qindex_to_q(i) <= q)
+break;
+}
+}
+static int estimate_max_q(VP9_COMP *cpi,
+FIRSTPASS_STATS *fpstats,
+int section_target_bandwitdh) {
+int q;
+int num_mbs = cpi->common.MBs;
+int target_norm_bits_per_mb;
+double section_err = fpstats->coded_error / fpstats->count;
+double sr_correction;
+double err_per_mb = section_err / num_mbs;
+double err_correction_factor;
+double speed_correction = 1.0;
+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);
+// Look at the drop in prediction quality between the last frame
+// and the GF buffer (which contained an older frame).
+if (fpstats->sr_coded_error > fpstats->coded_error) {
+double sr_err_diff = (fpstats->sr_coded_error - fpstats->coded_error) /
+(fpstats->count * cpi->common.MBs);
+sr_correction = fclamp(pow(sr_err_diff / 32.0, 0.25), 0.75, 1.25);
+} else {
+sr_correction = 0.75;
+}
+// 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 = (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 = fclamp(
+cpi->twopass.est_max_qcorrection_factor, 0.1, 10.0);
+}
+// Corrections for higher compression speed settings
+// (reduced compression expected)
+// FIXME(jimbankoski): Once we settle on vp9 speed features we need to
+// change this code.
+if (cpi->compressor_speed == 1)
+speed_correction = cpi->oxcf.cpu_used <= 5 ?
+1.04 + (/*cpi->oxcf.cpu_used*/0 * 0.04) :
+1.25;
+// 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;
+err_correction_factor = calc_correction_factor(err_per_mb,
+ERR_DIVISOR, 0.4, 0.90, q) *
+sr_correction * speed_correction *
+cpi->twopass.est_max_qcorrection_factor;
+bits_per_mb_at_this_q = vp9_bits_per_mb(INTER_FRAME, q,
+err_correction_factor);
+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.
+// PGW TODO.. This code is broken for the extended Q range
+if (cpi->ni_frames > ((int)cpi->twopass.total_stats.count >> 8) &&
+cpi->ni_frames > 25)
+adjust_maxq_qrange(cpi);
+return q;
+}
+// For cq mode estimate a cq level that matches the observed
+// complexity and data rate.
+static int estimate_cq(VP9_COMP *cpi,
+FIRSTPASS_STATS *fpstats,
+int section_target_bandwitdh) {
+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 sr_err_diff;
+double sr_correction;
+double speed_correction = 1.0;
+double clip_iiratio;
+double clip_iifactor;
+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 == 1) {
+if (cpi->oxcf.cpu_used <= 5)
+speed_correction = 1.04 + (/*cpi->oxcf.cpu_used*/ 0 * 0.04);
+else
+speed_correction = 1.25;
+}
+// Look at the drop in prediction quality between the last frame
+// and the GF buffer (which contained an older frame).
+if (fpstats->sr_coded_error > fpstats->coded_error) {
+sr_err_diff =
+(fpstats->sr_coded_error - fpstats->coded_error) /
+(fpstats->count * cpi->common.MBs);
+sr_correction = (sr_err_diff / 32.0);
+sr_correction = pow(sr_correction, 0.25);
+if (sr_correction < 0.75)
+sr_correction = 0.75;
+else if (sr_correction > 1.25)
+sr_correction = 1.25;
+} else {
+sr_correction = 0.75;
+}
+// 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, 0.4, 0.90, q) *
+sr_correction * speed_correction * clip_iifactor;
+bits_per_mb_at_this_q =
+vp9_bits_per_mb(INTER_FRAME, q, err_correction_factor);
+if (bits_per_mb_at_this_q <= target_norm_bits_per_mb)
+break;
+}
+// Clip value to range "best allowed to (worst allowed - 1)"
+q = select_cq_level(q);
+if (q >= cpi->worst_quality)
+q = cpi->worst_quality - 1;
+if (q < cpi->best_quality)
+q = cpi->best_quality;
+return q;
+}
+extern void vp9_new_framerate(VP9_COMP *cpi, double framerate);
+void vp9_init_second_pass(VP9_COMP *cpi) {
+FIRSTPASS_STATS this_frame;
+FIRSTPASS_STATS *start_pos;
+double lower_bounds_min_rate = FRAME_OVERHEAD_BITS * cpi->oxcf.framerate;
+double two_pass_min_rate = (double)(cpi->oxcf.target_bandwidth *
+cpi->oxcf.two_pass_vbrmin_section / 100);
+if (two_pass_min_rate < lower_bounds_min_rate)
+two_pass_min_rate = lower_bounds_min_rate;
+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.
+vp9_new_framerate(cpi, 10000000.0 * cpi->twopass.total_stats.count /
+cpi->twopass.total_stats.duration);
+cpi->output_framerate = cpi->oxcf.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;
+// This variable monitors how far behind the second ref update is lagging
+cpi->twopass.sr_update_lag = 1;
+// 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 the 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 vp9_end_second_pass(VP9_COMP *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(VP9_COMP *cpi,
+FIRSTPASS_STATS *next_frame) {
+double prediction_decay_rate;
+double second_ref_decay;
+double mb_sr_err_diff;
+// Initial basis is the % mbs inter coded
+prediction_decay_rate = next_frame->pcnt_inter;
+// Look at the observed drop in prediction quality between the last frame
+// and the GF buffer (which contains an older frame).
+mb_sr_err_diff = (next_frame->sr_coded_error - next_frame->coded_error) /
+cpi->common.MBs;
+if (mb_sr_err_diff <= 512.0) {
+second_ref_decay = 1.0 - (mb_sr_err_diff / 512.0);
+second_ref_decay = pow(second_ref_decay, 0.5);
+if (second_ref_decay < 0.85)
+second_ref_decay = 0.85;
+else if (second_ref_decay > 1.0)
+second_ref_decay = 1.0;
+} else {
+second_ref_decay = 0.85;
+}
+if (second_ref_decay < prediction_decay_rate)
+prediction_decay_rate = second_ref_decay;
+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(
+VP9_COMP *cpi,
+int frame_interval,
+int still_interval,
+double loop_decay_rate,
+double last_decay_rate) {
+int trans_to_still = 0;
+// Break clause to detect very still sections after motion
+// For example a static image after a fade or other transition
+// instead of a clean scene cut.
+if (frame_interval > MIN_GF_INTERVAL &&
+loop_decay_rate >= 0.999 &&
+last_decay_rate < 0.9) {
+int j;
+FIRSTPASS_STATS *position = cpi->twopass.stats_in;
+FIRSTPASS_STATS tmp_next_frame;
+double zz_inter;
+// 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;
+zz_inter =
+(tmp_next_frame.pcnt_inter - tmp_next_frame.pcnt_motion);
+if (zz_inter < 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(VP9_COMP *cpi, int offset) {
+FIRSTPASS_STATS next_frame;
+int flash_detected = 0;
+// Read the frame data.
+// The return is FALSE (no flash detected) if not a valid frame
+if (read_frame_stats(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;
+}
+return flash_detected;
+}
+// Update the motion related elements to the GF arf boost calculation
+static void accumulate_frame_motion_stats(
+FIRSTPASS_STATS *this_frame,
+double *this_frame_mv_in_out,
+double *mv_in_out_accumulator,
+double *abs_mv_in_out_accumulator,
+double *mv_ratio_accumulator) {
+// double this_frame_mv_in_out;
+double this_frame_mvr_ratio;
+double this_frame_mvc_ratio;
+double motion_pct;
+// Accumulate motion stats.
+motion_pct = this_frame->pcnt_motion;
+// Accumulate Motion In/Out of frame stats
+*this_frame_mv_in_out = this_frame->mv_in_out_count * motion_pct;
+*mv_in_out_accumulator += this_frame->mv_in_out_count * motion_pct;
+*abs_mv_in_out_accumulator +=
+fabs(this_frame->mv_in_out_count * motion_pct);
+// Accumulate a measure of how uniform (or conversely how random)
+// the motion field is. (A ratio of absmv / mv)
+if (motion_pct > 0.05) {
+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(
+VP9_COMP *cpi,
+FIRSTPASS_STATS *this_frame,
+double this_frame_mv_in_out) {
+double frame_boost;
+// Underlying boost factor is based on inter intra error ratio
+if (this_frame->intra_error > cpi->twopass.gf_intra_err_min)
+frame_boost = (IIFACTOR * this_frame->intra_error /
+DOUBLE_DIVIDE_CHECK(this_frame->coded_error));
+else
+frame_boost = (IIFACTOR * cpi->twopass.gf_intra_err_min /
+DOUBLE_DIVIDE_CHECK(this_frame->coded_error));
+// Increase boost for frames where new data coming into frame
+// (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;
+}
+static int calc_arf_boost(VP9_COMP *cpi, int offset,
+int f_frames, int b_frames,
+int *f_boost, int *b_boost) {
+FIRSTPASS_STATS this_frame;
+int i;
+double boost_score = 0.0;
+double mv_ratio_accumulator = 0.0;
+double decay_accumulator = 1.0;
+double this_frame_mv_in_out = 0.0;
+double mv_in_out_accumulator = 0.0;
+double abs_mv_in_out_accumulator = 0.0;
+int arf_boost;
+int flash_detected = 0;
+// Search forward from the proposed arf/next gf position
+for (i = 0; i < f_frames; i++) {
+if (read_frame_stats(cpi, &this_frame, (i + offset)) == EOF)
+break;
+// Update the motion related elements to the boost calculation
+accumulate_frame_motion_stats(&this_frame,
+&this_frame_mv_in_out, &mv_in_out_accumulator,
+&abs_mv_in_out_accumulator,
+&mv_ratio_accumulator);
+// We want to discount the flash frame itself and the recovery
+// frame that follows as both will have poor scores.
+flash_detected = detect_flash(cpi, (i + offset)) ||
+detect_flash(cpi, (i + offset + 1));
+// Cumulative effect of prediction quality decay
+if (!flash_detected) {
+decay_accumulator *= get_prediction_decay_rate(cpi, &this_frame);
+decay_accumulator = decay_accumulator < MIN_DECAY_FACTOR
+? MIN_DECAY_FACTOR : decay_accumulator;
+}
+boost_score += (decay_accumulator *
+calc_frame_boost(cpi, &this_frame, this_frame_mv_in_out));
+}
+*f_boost = (int)boost_score;
+// Reset for backward looking loop
+boost_score = 0.0;
+mv_ratio_accumulator = 0.0;
+decay_accumulator = 1.0;
+this_frame_mv_in_out = 0.0;
+mv_in_out_accumulator = 0.0;
+abs_mv_in_out_accumulator = 0.0;
+// Search backward towards last gf position
+for (i = -1; i >= -b_frames; i--) {
+if (read_frame_stats(cpi, &this_frame, (i + offset)) == EOF)
+break;
+// Update the motion related elements to the boost calculation
+accumulate_frame_motion_stats(&this_frame,
+&this_frame_mv_in_out, &mv_in_out_accumulator,
+&abs_mv_in_out_accumulator,
+&mv_ratio_accumulator);
+// We want to discount the the flash frame itself and the recovery
+// frame that follows as both will have poor scores.
+flash_detected = detect_flash(cpi, (i + offset)) ||
+detect_flash(cpi, (i + offset + 1));
+// Cumulative effect of prediction quality decay
+if (!flash_detected) {
+decay_accumulator *= get_prediction_decay_rate(cpi, &this_frame);
+decay_accumulator = decay_accumulator < MIN_DECAY_FACTOR
+? MIN_DECAY_FACTOR : decay_accumulator;
+}
+boost_score += (decay_accumulator *
+calc_frame_boost(cpi, &this_frame, this_frame_mv_in_out));
+}
+*b_boost = (int)boost_score;
+arf_boost = (*f_boost + *b_boost);
+if (arf_boost < ((b_frames + f_frames) * 20))
+arf_boost = ((b_frames + f_frames) * 20);
+return arf_boost;
+}
+#if CONFIG_MULTIPLE_ARF
+// Work out the frame coding order for a GF or an ARF group.
+// The current implementation codes frames in their natural order for a
+// GF group, and inserts additional ARFs into an ARF group using a
+// binary split approach.
+// NOTE: this function is currently implemented recursively.
+static void schedule_frames(VP9_COMP *cpi, const int start, const int end,
+const int arf_idx, const int gf_or_arf_group,
+const int level) {
+int i, abs_end, half_range;
+int *cfo = cpi->frame_coding_order;
+int idx = cpi->new_frame_coding_order_period;
+// If (end < 0) an ARF should be coded at position (-end).
+assert(start >= 0);
+// printf("start:%d end:%d\n", start, end);
+// GF Group: code frames in logical order.
+if (gf_or_arf_group == 0) {
+assert(end >= start);
+for (i = start; i <= end; ++i) {
+cfo[idx] = i;
+cpi->arf_buffer_idx[idx] = arf_idx;
+cpi->arf_weight[idx] = -1;
+++idx;
+}
+cpi->new_frame_coding_order_period = idx;
+return;
+}
+// ARF Group: work out the ARF schedule.
+// Mark ARF frames as negative.
+if (end < 0) {
+// printf("start:%d end:%d\n", -end, -end);
+// ARF frame is at the end of the range.
+cfo[idx] = end;
+// What ARF buffer does this ARF use as predictor.
+cpi->arf_buffer_idx[idx] = (arf_idx > 2) ? (arf_idx - 1) : 2;
+cpi->arf_weight[idx] = level;
+++idx;
+abs_end = -end;
+} else {
+abs_end = end;
+}
+half_range = (abs_end - start) >> 1;
+// ARFs may not be adjacent, they must be separated by at least
+// MIN_GF_INTERVAL non-ARF frames.
+if ((start + MIN_GF_INTERVAL) >= (abs_end - MIN_GF_INTERVAL)) {
+// printf("start:%d end:%d\n", start, abs_end);
+// Update the coding order and active ARF.
+for (i = start; i <= abs_end; ++i) {
+cfo[idx] = i;
+cpi->arf_buffer_idx[idx] = arf_idx;
+cpi->arf_weight[idx] = -1;
+++idx;
+}
+cpi->new_frame_coding_order_period = idx;
+} else {
+// Place a new ARF at the mid-point of the range.
+cpi->new_frame_coding_order_period = idx;
+schedule_frames(cpi, start, -(start + half_range), arf_idx + 1,
+gf_or_arf_group, level + 1);
+schedule_frames(cpi, start + half_range + 1, abs_end, arf_idx,
+gf_or_arf_group, level + 1);
+}
+}
+#define FIXED_ARF_GROUP_SIZE 16
+void define_fixed_arf_period(VP9_COMP *cpi) {
+int i;
+int max_level = INT_MIN;
+assert(cpi->multi_arf_enabled);
+assert(cpi->oxcf.lag_in_frames >= FIXED_ARF_GROUP_SIZE);
+// Save the weight of the last frame in the sequence before next
+// sequence pattern overwrites it.
+cpi->this_frame_weight = cpi->arf_weight[cpi->sequence_number];
+assert(cpi->this_frame_weight >= 0);
+// Initialize frame coding order variables.
+cpi->new_frame_coding_order_period = 0;
+cpi->next_frame_in_order = 0;
+cpi->arf_buffered = 0;
+vp9_zero(cpi->frame_coding_order);
+vp9_zero(cpi->arf_buffer_idx);
+vpx_memset(cpi->arf_weight, -1, sizeof(cpi->arf_weight));
+if (cpi->twopass.frames_to_key <= (FIXED_ARF_GROUP_SIZE + 8)) {
+// Setup a GF group close to the keyframe.
+cpi->source_alt_ref_pending = 0;
+cpi->baseline_gf_interval = cpi->twopass.frames_to_key;
+schedule_frames(cpi, 0, (cpi->baseline_gf_interval - 1), 2, 0, 0);
+} else {
+// Setup a fixed period ARF group.
+cpi->source_alt_ref_pending = 1;
+cpi->baseline_gf_interval = FIXED_ARF_GROUP_SIZE;
+schedule_frames(cpi, 0, -(cpi->baseline_gf_interval - 1), 2, 1, 0);
+}
+// Replace level indicator of -1 with correct level.
+for (i = 0; i < cpi->new_frame_coding_order_period; ++i) {
+if (cpi->arf_weight[i] > max_level) {
+max_level = cpi->arf_weight[i];
+}
+}
+++max_level;
+for (i = 0; i < cpi->new_frame_coding_order_period; ++i) {
+if (cpi->arf_weight[i] == -1) {
+cpi->arf_weight[i] = max_level;
+}
+}
+cpi->max_arf_level = max_level;
+#if 0
+printf("\nSchedule: ");
+for (i = 0; i < cpi->new_frame_coding_order_period; ++i) {
+printf("%4d ", cpi->frame_coding_order[i]);
+}
+printf("\n");
+printf("ARFref:   ");
+for (i = 0; i < cpi->new_frame_coding_order_period; ++i) {
+printf("%4d ", cpi->arf_buffer_idx[i]);
+}
+printf("\n");
+printf("Weight:   ");
+for (i = 0; i < cpi->new_frame_coding_order_period; ++i) {
+printf("%4d ", cpi->arf_weight[i]);
+}
+printf("\n");
+#endif
+}
+#endif
+// Analyse and define a gf/arf group.
+static void define_gf_group(VP9_COMP *cpi, FIRSTPASS_STATS *this_frame) {
+FIRSTPASS_STATS next_frame = { 0 };
+FIRSTPASS_STATS *start_pos;
+int i;
+double boost_score = 0.0;
+double old_boost_score = 0.0;
+double gf_group_err = 0.0;
+double gf_first_frame_err = 0.0;
+double mod_frame_err = 0.0;
+double mv_ratio_accumulator = 0.0;
+double decay_accumulator = 1.0;
+double zero_motion_accumulator = 1.0;
+double loop_decay_rate = 1.00;          // Starting decay rate
+double last_loop_decay_rate = 1.00;
+double this_frame_mv_in_out = 0.0;
+double mv_in_out_accumulator = 0.0;
+double abs_mv_in_out_accumulator = 0.0;
+double mv_ratio_accumulator_thresh;
+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 f_boost = 0;
+int b_boost = 0;
+int flash_detected;
+int active_max_gf_interval;
+cpi->twopass.gf_group_bits = 0;
+vp9_clear_system_state();  // __asm emms;
+start_pos = cpi->twopass.stats_in;
+// Load stats for the current frame.
+mod_frame_err = calculate_modified_err(cpi, this_frame);
+// Note the error of the frame at the start of the group (this will be
+// the GF frame error if we code a normal gf
+gf_first_frame_err = mod_frame_err;
+// 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;
+// Motion breakout threshold for loop below depends on image size.
+mv_ratio_accumulator_thresh = (cpi->common.width + cpi->common.height) / 10.0;
+// Work out a maximum interval for the GF.
+// If the image appears completely static we can extend beyond this.
+// The value chosen depends on the active Q range. At low Q we have
+// bits to spare and are better with a smaller interval and smaller boost.
+// At high Q when there are few bits to spare we are better with a longer
+// interval to spread the cost of the GF.
+active_max_gf_interval =
+12 + ((int)vp9_convert_qindex_to_q(cpi->active_worst_quality) >> 5);
+if (active_max_gf_interval > cpi->max_gf_interval)
+active_max_gf_interval = cpi->max_gf_interval;
+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++;    // Increment the loop counter
+// Accumulate error score of frames in this gf group
+mod_frame_err = calculate_modified_err(cpi, this_frame);
+gf_group_err += mod_frame_err;
+if (EOF == input_stats(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(&next_frame,
+&this_frame_mv_in_out, &mv_in_out_accumulator,
+&abs_mv_in_out_accumulator,
+&mv_ratio_accumulator);
+// Cumulative effect of prediction quality decay
+if (!flash_detected) {
+last_loop_decay_rate = loop_decay_rate;
+loop_decay_rate = get_prediction_decay_rate(cpi, &next_frame);
+decay_accumulator = decay_accumulator * loop_decay_rate;
+// Monitor for static sections.
+if ((next_frame.pcnt_inter - next_frame.pcnt_motion) <
+zero_motion_accumulator) {
+zero_motion_accumulator =
+(next_frame.pcnt_inter - next_frame.pcnt_motion);
+}
+// Break clause to detect very still sections after motion
+// (for example a static image after a fade or other transition).
+if (detect_transition_to_still(cpi, i, 5, loop_decay_rate,
+last_loop_decay_rate)) {
+allow_alt_ref = 0;
+break;
+}
+}
+// Calculate a boost number for this frame
+boost_score +=
+(decay_accumulator *
+calc_frame_boost(cpi, &next_frame, this_frame_mv_in_out));
+// Break out conditions.
+if (
+// Break at cpi->max_gf_interval unless almost totally static
+(i >= active_max_gf_interval && (zero_motion_accumulator < 0.995)) ||
+(
+// Don't break out with a very short interval
+(i > MIN_GF_INTERVAL) &&
+// Don't break out very close to a key frame
+((cpi->twopass.frames_to_key - i) >= MIN_GF_INTERVAL) &&
+((boost_score > 125.0) || (next_frame.pcnt_inter < 0.75)) &&
+(!flash_detected) &&
+((mv_ratio_accumulator > mv_ratio_accumulator_thresh) ||
+(abs_mv_in_out_accumulator > 3.0) ||
+(mv_in_out_accumulator < -2.0) ||
+((boost_score - old_boost_score) < IIFACTOR)))) {
+boost_score = old_boost_score;
+break;
+}
+*this_frame = next_frame;
+old_boost_score = boost_score;
+}
+cpi->gf_zeromotion_pct = (int)(zero_motion_accumulator * 1000.0);
+// Don't allow a 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;
+}
+}
+}
+// Set the interval until the next gf or arf.
+cpi->baseline_gf_interval = i;
+#if CONFIG_MULTIPLE_ARF
+if (cpi->multi_arf_enabled) {
+// Initialize frame coding order variables.
+cpi->new_frame_coding_order_period = 0;
+cpi->next_frame_in_order = 0;
+cpi->arf_buffered = 0;
+vp9_zero(cpi->frame_coding_order);
+vp9_zero(cpi->arf_buffer_idx);
+vpx_memset(cpi->arf_weight, -1, sizeof(cpi->arf_weight));
+}
+#endif
+// Should we use the alternate reference frame
+if (allow_alt_ref &&
+(i < cpi->oxcf.lag_in_frames) &&
+(i >= MIN_GF_INTERVAL) &&
+// dont use ARF very near next kf
+(i <= (cpi->twopass.frames_to_key - MIN_GF_INTERVAL)) &&
+((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)) &&
+(boost_score > 100)) {
+// Alternative boost calculation for alt ref
+cpi->gfu_boost = calc_arf_boost(cpi, 0, (i - 1), (i - 1), &f_boost,
+&b_boost);
+cpi->source_alt_ref_pending = 1;
+#if CONFIG_MULTIPLE_ARF
+// Set the ARF schedule.
+if (cpi->multi_arf_enabled) {
+schedule_frames(cpi, 0, -(cpi->baseline_gf_interval - 1), 2, 1, 0);
+}
+#endif
+} else {
+cpi->gfu_boost = (int)boost_score;
+cpi->source_alt_ref_pending = 0;
+#if CONFIG_MULTIPLE_ARF
+// Set the GF schedule.
+if (cpi->multi_arf_enabled) {
+schedule_frames(cpi, 0, cpi->baseline_gf_interval - 1, 2, 0, 0);
+assert(cpi->new_frame_coding_order_period == cpi->baseline_gf_interval);
+}
+#endif
+}
+#if CONFIG_MULTIPLE_ARF
+if (cpi->multi_arf_enabled && (cpi->common.frame_type != KEY_FRAME)) {
+int max_level = INT_MIN;
+// Replace level indicator of -1 with correct level.
+for (i = 0; i < cpi->frame_coding_order_period; ++i) {
+if (cpi->arf_weight[i] > max_level) {
+max_level = cpi->arf_weight[i];
+}
+}
+++max_level;
+for (i = 0; i < cpi->frame_coding_order_period; ++i) {
+if (cpi->arf_weight[i] == -1) {
+cpi->arf_weight[i] = max_level;
+}
+}
+cpi->max_arf_level = max_level;
+}
+#if 0
+if (cpi->multi_arf_enabled) {
+printf("\nSchedule: ");
+for (i = 0; i < cpi->new_frame_coding_order_period; ++i) {
+printf("%4d ", cpi->frame_coding_order[i]);
+}
+printf("\n");
+printf("ARFref:   ");
+for (i = 0; i < cpi->new_frame_coding_order_period; ++i) {
+printf("%4d ", cpi->arf_buffer_idx[i]);
+}
+printf("\n");
+printf("Weight:   ");
+for (i = 0; i < cpi->new_frame_coding_order_period; ++i) {
+printf("%4d ", cpi->arf_weight[i]);
+}
+printf("\n");
+}
+#endif
+#endif
+// 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 allocation_chunks;
+int q = cpi->oxcf.fixed_q < 0 ? cpi->last_q[INTER_FRAME]
+: cpi->oxcf.fixed_q;
+int gf_bits;
+int boost = (cpi->gfu_boost * vp9_gfboost_qadjust(q)) / 100;
+// Set max and minimum boost and hence minimum allocation
+boost = clamp(boost, 125, (cpi->baseline_gf_interval + 1) * 200);
+if (cpi->source_alt_ref_pending && i == 0)
+allocation_chunks = ((cpi->baseline_gf_interval + 1) * 100) + boost;
+else
+allocation_chunks = (cpi->baseline_gf_interval * 100) + (boost - 100);
+// Prevent overflow
+if (boost > 1023) {
+int divisor = boost >> 10;
+boost /= divisor;
+allocation_chunks /= divisor;
+}
+// Calculate the number of bits to be spent on the gf or arf based on
+// the boost number
+gf_bits = (int)((double)boost * (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 =
+(double)cpi->twopass.kf_group_bits  *
+(mod_frame_err * (double)cpi->baseline_gf_interval) /
+DOUBLE_DIVIDE_CHECK(cpi->twopass.kf_group_error_left);
+int alt_gf_bits = (int)((double)boost * (alt_gf_grp_bits /
+(double)allocation_chunks));
+if (gf_bits > alt_gf_bits)
+gf_bits = alt_gf_bits;
+} else {
+// If it is harder than other frames in the group make sure it at
+// least receives an allocation in keeping with its relative error
+// score, otherwise it may be worse off than an "un-boosted" frame.
+int alt_gf_bits = (int)((double)cpi->twopass.kf_group_bits *
+mod_frame_err /
+DOUBLE_DIVIDE_CHECK(cpi->twopass.kf_group_error_left));
+if (alt_gf_bits > gf_bits)
+gf_bits = alt_gf_bits;
+}
+// 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 remaining
+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 = (int64_t)(gf_group_err
+- gf_first_frame_err);
+else
+cpi->twopass.gf_group_error_left = (int64_t)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 divide by 0 in the
+// calculation of alt_extra_bits.
+if (cpi->baseline_gf_interval >= 3) {
+const int boost = cpi->source_alt_ref_pending ? b_boost : cpi->gfu_boost;
+if (boost >= 150) {
+int alt_extra_bits;
+int pct_extra = (boost - 100) / 50;
+pct_extra = (pct_extra > 20) ? 20 : pct_extra;
+alt_extra_bits = (int)((cpi->twopass.gf_group_bits * pct_extra) / 100);
+cpi->twopass.gf_group_bits -= alt_extra_bits;
+}
+}
+}
+if (cpi->common.frame_type != KEY_FRAME) {
+FIRSTPASS_STATS sectionstats;
+zero_stats(&sectionstats);
+reset_fpf_position(cpi, start_pos);
+for (i = 0; i < cpi->baseline_gf_interval; i++) {
+input_stats(cpi, &next_frame);
+accumulate_stats(&sectionstats, &next_frame);
+}
+avg_stats(&sectionstats);
+cpi->twopass.section_intra_rating = (int)
+(sectionstats.intra_error /
+DOUBLE_DIVIDE_CHECK(sectionstats.coded_error));
+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(VP9_COMP *cpi, FIRSTPASS_STATS *this_frame) {
+int target_frame_size;
+double modified_err;
+double err_fraction;
+// Max for a single frame.
+int max_bits = frame_max_bits(cpi);
+// Calculate modified prediction error used in bit allocation.
+modified_err = calculate_modified_err(cpi, this_frame);
+if (cpi->twopass.gf_group_error_left > 0)
+// What portion of the remaining GF group error is used by this frame.
+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 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 -= (int64_t)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;
+// Per frame bit target for this frame.
+cpi->per_frame_bandwidth = target_frame_size;
+}
+// Make a damped adjustment to the active max q.
+static int adjust_active_maxq(int old_maxqi, int new_maxqi) {
+int i;
+const double old_q = vp9_convert_qindex_to_q(old_maxqi);
+const double new_q = vp9_convert_qindex_to_q(new_maxqi);
+const double target_q = ((old_q * 7.0) + new_q) / 8.0;
+if (target_q > old_q) {
+for (i = old_maxqi; i <= new_maxqi; i++)
+if (vp9_convert_qindex_to_q(i) >= target_q)
+return i;
+} else {
+for (i = old_maxqi; i >= new_maxqi; i--)
+if (vp9_convert_qindex_to_q(i) <= target_q)
+return i;
+}
+return new_maxqi;
+}
+void vp9_second_pass(VP9_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;
+if (!cpi->twopass.stats_in)
+return;
+vp9_clear_system_state();
+if (cpi->oxcf.end_usage == USAGE_CONSTANT_QUALITY) {
+cpi->active_worst_quality = cpi->oxcf.cq_level;
+} else {
+// Special case code for first frame.
+if (cpi->common.current_video_frame == 0) {
+int section_target_bandwidth =
+(int)(cpi->twopass.bits_left / frames_left);
+cpi->twopass.est_max_qcorrection_factor = 1.0;
+// Set a cq_level in constrained quality mode.
+// Commenting this code out for now since it does not seem to be
+// working well.
+/*
+if (cpi->oxcf.end_usage == USAGE_CONSTRAINED_QUALITY) {
+int est_cq = estimate_cq(cpi, &cpi->twopass.total_left_stats,
+section_target_bandwidth);
+if (est_cq > cpi->cq_target_quality)
+cpi->cq_target_quality = est_cq;
+else
+cpi->cq_target_quality = cpi->oxcf.cq_level;
+}
+*/
+// 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,
+section_target_bandwidth);
+cpi->active_worst_quality = tmp_q;
+cpi->ni_av_qi = tmp_q;
+cpi->avg_q = vp9_convert_qindex_to_q(tmp_q);
+// 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
+adjust_maxq_qrange(cpi);
+}
+// 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)) {
+int section_target_bandwidth =
+(int)(cpi->twopass.bits_left / frames_left);
+if (frames_left < 1)
+frames_left = 1;
+tmp_q = estimate_max_q(
+cpi,
+&cpi->twopass.total_left_stats,
+section_target_bandwidth);
+// Make a damped adjustment to active max Q
+cpi->active_worst_quality =
+adjust_active_maxq(cpi->active_worst_quality, tmp_q);
+}
+}
+vp9_zero(this_frame);
+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
+this_frame_copy = this_frame;
+find_next_key_frame(cpi, &this_frame_copy);
+}
+// 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
+this_frame_copy = this_frame;
+cpi->gf_zeromotion_pct = 0;
+#if CONFIG_MULTIPLE_ARF
+if (cpi->multi_arf_enabled) {
+define_fixed_arf_period(cpi);
+} else {
+#endif
+define_gf_group(cpi, &this_frame_copy);
+#if CONFIG_MULTIPLE_ARF
+}
+#endif
+if (cpi->gf_zeromotion_pct > 995) {
+// As long as max_thresh for encode breakout is small enough, it is ok
+// to enable it for no-show frame, i.e. set enable_encode_breakout to 2.
+if (!cpi->common.show_frame)
+cpi->enable_encode_breakout = 0;
+else
+cpi->enable_encode_breakout = 2;
+}
+// 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;
+this_frame_copy = this_frame;
+assign_std_frame_bits(cpi, &this_frame_copy);
+cpi->per_frame_bandwidth = bak;
+}
+} else {
+// Otherwise this is an ordinary frame
+// Assign bits from those allocated to the GF group
+this_frame_copy =  this_frame;
+assign_std_frame_bits(cpi, &this_frame_copy);
+}
+// Keep a globally available copy of this and the next frame's iiratio.
+cpi->twopass.this_iiratio = (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 = (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;
+cpi->twopass.frames_to_key--;
+// Update the total stats remaining structure
+subtract_stats(&cpi->twopass.total_left_stats, &this_frame);
+}
+static int test_candidate_kf(VP9_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) < .35) &&
+((this_frame->intra_error /
+DOUBLE_DIVIDE_CHECK(this_frame->coded_error)) < 2.5) &&
+((fabs(last_frame->coded_error - this_frame->coded_error) /
+DOUBLE_DIVIDE_CHECK(this_frame->coded_error) >
+.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;
+local_next_frame = *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);
+// decay_accumulator = decay_accumulator * local_next_frame.pcnt_inter;
+// Keep a running total
+boost_score += (decay_accumulator * next_iiratio);
+// Test various breakout clauses
+if ((local_next_frame.pcnt_inter < 0.05) ||
+(next_iiratio < 1.5) ||
+(((local_next_frame.pcnt_inter -
+local_next_frame.pcnt_neutral) < 0.20) &&
+(next_iiratio < 3.0)) ||
+((boost_score - old_boost_score) < 3.0) ||
+(local_next_frame.intra_error < 200)
+) {
+break;
+}
+old_boost_score = boost_score;
+// Get the next frame details
+if (EOF == input_stats(cpi, &local_next_frame))
+break;
+}
+// If there is tolerable prediction for at least the next 3 frames then
+// break out else discard this potential key frame and move on
+if (boost_score > 30.0 && (i > 3)) {
+is_viable_kf = 1;
+} else {
+// Reset the file position
+reset_fpf_position(cpi, start_pos);
+is_viable_kf = 0;
+}
+}
+return is_viable_kf;
+}
+static void find_next_key_frame(VP9_COMP *cpi, FIRSTPASS_STATS *this_frame) {
+int i, j;
+FIRSTPASS_STATS last_frame;
+FIRSTPASS_STATS first_frame;
+FIRSTPASS_STATS next_frame;
+FIRSTPASS_STATS *start_position;
+double decay_accumulator = 1.0;
+double zero_motion_accumulator = 1.0;
+double boost_score = 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};
+vp9_zero(next_frame);
+vp9_clear_system_state();  // __asm emms;
+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
+first_frame = *this_frame;
+cpi->twopass.kf_group_bits = 0;        // Total bits available to kf group
+cpi->twopass.kf_group_error_left = 0;  // Group modified error score.
+kf_mod_err = calculate_modified_err(cpi, this_frame);
+// find the next keyframe
+i = 0;
+while (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 a the next frame's stats
+last_frame = *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 (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 *= recent_loop_decay[j];
+// Special check for transition or high motion followed by a
+// to a static scene.
+if (detect_transition_to_still(cpi, i, cpi->key_frame_frequency - 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
+tmp_frame = 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;
+} 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;
+loop_decay_rate = 1.00;       // Starting decay rate
+// Scan through the kf group collating various stats.
+for (i = 0; i < cpi->twopass.frames_to_key; i++) {
+double r;
+if (EOF == input_stats(cpi, &next_frame))
+break;
+// Monitor for static sections.
+if ((next_frame.pcnt_inter - next_frame.pcnt_motion) <
+zero_motion_accumulator) {
+zero_motion_accumulator =
+(next_frame.pcnt_inter - next_frame.pcnt_motion);
+}
+// For the first few frames collect data to decide kf boost.
+if (i <= (cpi->max_gf_interval * 2)) {
+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
+if (!detect_flash(cpi, 0)) {
+loop_decay_rate = get_prediction_decay_rate(cpi, &next_frame);
+decay_accumulator = decay_accumulator * loop_decay_rate;
+decay_accumulator = decay_accumulator < MIN_DECAY_FACTOR
+? MIN_DECAY_FACTOR : decay_accumulator;
+}
+boost_score += (decay_accumulator * r);
+}
+}
+{
+FIRSTPASS_STATS sectionstats;
+zero_stats(&sectionstats);
+reset_fpf_position(cpi, start_position);
+for (i = 0; i < cpi->twopass.frames_to_key; i++) {
+input_stats(cpi, &next_frame);
+accumulate_stats(&sectionstats, &next_frame);
+}
+avg_stats(&sectionstats);
+cpi->twopass.section_intra_rating = (int)
+(sectionstats.intra_error
+/ DOUBLE_DIVIDE_CHECK(sectionstats.coded_error));
+}
+// 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 alt_kf_bits;
+if (kf_boost < (cpi->twopass.frames_to_key * 3))
+kf_boost = (cpi->twopass.frames_to_key * 3);
+if (kf_boost < 300)  // Min KF boost
+kf_boost = 300;
+// Make a note of baseline boost and the zero motion
+// accumulator value for use elsewhere.
+cpi->kf_boost = kf_boost;
+cpi->kf_zeromotion_pct = (int)(zero_motion_accumulator * 100.0);
+// 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
+// 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 (zero_motion_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;
+}
+// Prevent overflow
+if (kf_boost > 1028) {
+int divisor = kf_boost >> 10;
+kf_boost /= divisor;
+allocation_chunks /= divisor;
+}
+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));
+// 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 {
+// 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
+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;
+}

The Tor Browser / file comparison

comparison: media/libvpx/vp9/encoder/vp9_firstpass.c

media/libvpx/vp9/encoder/vp9_firstpass.c