FFmpeg/libavcodec/ratecontrol.c

1039 lines
34 KiB
C

/*
* Rate control for video encoders
*
* Copyright (c) 2002-2004 Michael Niedermayer <michaelni@gmx.at>
*
* This file is part of Libav.
*
* Libav is free software; you can redistribute it and/or
* modify it under the terms of the GNU Lesser General Public
* License as published by the Free Software Foundation; either
* version 2.1 of the License, or (at your option) any later version.
*
* Libav is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* Lesser General Public License for more details.
*
* You should have received a copy of the GNU Lesser General Public
* License along with Libav; if not, write to the Free Software
* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
*/
/**
* @file
* Rate control for video encoders.
*/
#include "libavutil/attributes.h"
#include "avcodec.h"
#include "ratecontrol.h"
#include "mpegvideo.h"
#include "libavutil/eval.h"
#undef NDEBUG // Always check asserts, the speed effect is far too small to disable them.
#include <assert.h>
#ifndef M_E
#define M_E 2.718281828
#endif
static int init_pass2(MpegEncContext *s);
static double get_qscale(MpegEncContext *s, RateControlEntry *rce,
double rate_factor, int frame_num);
void ff_write_pass1_stats(MpegEncContext *s)
{
snprintf(s->avctx->stats_out, 256,
"in:%d out:%d type:%d q:%d itex:%d ptex:%d mv:%d misc:%d "
"fcode:%d bcode:%d mc-var:%d var:%d icount:%d skipcount:%d hbits:%d;\n",
s->current_picture_ptr->f.display_picture_number,
s->current_picture_ptr->f.coded_picture_number,
s->pict_type,
s->current_picture.f.quality,
s->i_tex_bits,
s->p_tex_bits,
s->mv_bits,
s->misc_bits,
s->f_code,
s->b_code,
s->current_picture.mc_mb_var_sum,
s->current_picture.mb_var_sum,
s->i_count, s->skip_count,
s->header_bits);
}
static inline double qp2bits(RateControlEntry *rce, double qp)
{
if (qp <= 0.0) {
av_log(NULL, AV_LOG_ERROR, "qp<=0.0\n");
}
return rce->qscale * (double)(rce->i_tex_bits + rce->p_tex_bits + 1) / qp;
}
static inline double bits2qp(RateControlEntry *rce, double bits)
{
if (bits < 0.9) {
av_log(NULL, AV_LOG_ERROR, "bits<0.9\n");
}
return rce->qscale * (double)(rce->i_tex_bits + rce->p_tex_bits + 1) / bits;
}
av_cold int ff_rate_control_init(MpegEncContext *s)
{
RateControlContext *rcc = &s->rc_context;
int i, res;
static const char * const const_names[] = {
"PI",
"E",
"iTex",
"pTex",
"tex",
"mv",
"fCode",
"iCount",
"mcVar",
"var",
"isI",
"isP",
"isB",
"avgQP",
"qComp",
#if 0
"lastIQP",
"lastPQP",
"lastBQP",
"nextNonBQP",
#endif
"avgIITex",
"avgPITex",
"avgPPTex",
"avgBPTex",
"avgTex",
NULL
};
static double (* const func1[])(void *, double) = {
(void *)bits2qp,
(void *)qp2bits,
NULL
};
static const char * const func1_names[] = {
"bits2qp",
"qp2bits",
NULL
};
emms_c();
res = av_expr_parse(&rcc->rc_eq_eval,
s->avctx->rc_eq ? s->avctx->rc_eq : "tex^qComp",
const_names, func1_names, func1,
NULL, NULL, 0, s->avctx);
if (res < 0) {
av_log(s->avctx, AV_LOG_ERROR, "Error parsing rc_eq \"%s\"\n", s->avctx->rc_eq);
return res;
}
for (i = 0; i < 5; i++) {
rcc->pred[i].coeff = FF_QP2LAMBDA * 7.0;
rcc->pred[i].count = 1.0;
rcc->pred[i].decay = 0.4;
rcc->i_cplx_sum [i] =
rcc->p_cplx_sum [i] =
rcc->mv_bits_sum[i] =
rcc->qscale_sum [i] =
rcc->frame_count[i] = 1; // 1 is better because of 1/0 and such
rcc->last_qscale_for[i] = FF_QP2LAMBDA * 5;
}
rcc->buffer_index = s->avctx->rc_initial_buffer_occupancy;
if (s->flags & CODEC_FLAG_PASS2) {
int i;
char *p;
/* find number of pics */
p = s->avctx->stats_in;
for (i = -1; p; i++)
p = strchr(p + 1, ';');
i += s->max_b_frames;
if (i <= 0 || i >= INT_MAX / sizeof(RateControlEntry))
return -1;
rcc->entry = av_mallocz(i * sizeof(RateControlEntry));
rcc->num_entries = i;
/* init all to skipped p frames
* (with b frames we might have a not encoded frame at the end FIXME) */
for (i = 0; i < rcc->num_entries; i++) {
RateControlEntry *rce = &rcc->entry[i];
rce->pict_type = rce->new_pict_type = AV_PICTURE_TYPE_P;
rce->qscale = rce->new_qscale = FF_QP2LAMBDA * 2;
rce->misc_bits = s->mb_num + 10;
rce->mb_var_sum = s->mb_num * 100;
}
/* read stats */
p = s->avctx->stats_in;
for (i = 0; i < rcc->num_entries - s->max_b_frames; i++) {
RateControlEntry *rce;
int picture_number;
int e;
char *next;
next = strchr(p, ';');
if (next) {
(*next) = 0; // sscanf in unbelievably slow on looong strings // FIXME copy / do not write
next++;
}
e = sscanf(p, " in:%d ", &picture_number);
assert(picture_number >= 0);
assert(picture_number < rcc->num_entries);
rce = &rcc->entry[picture_number];
e += sscanf(p, " in:%*d out:%*d type:%d q:%f itex:%d ptex:%d mv:%d misc:%d fcode:%d bcode:%d mc-var:%d var:%d icount:%d skipcount:%d hbits:%d",
&rce->pict_type, &rce->qscale, &rce->i_tex_bits, &rce->p_tex_bits,
&rce->mv_bits, &rce->misc_bits,
&rce->f_code, &rce->b_code,
&rce->mc_mb_var_sum, &rce->mb_var_sum,
&rce->i_count, &rce->skip_count, &rce->header_bits);
if (e != 14) {
av_log(s->avctx, AV_LOG_ERROR,
"statistics are damaged at line %d, parser out=%d\n",
i, e);
return -1;
}
p = next;
}
if (init_pass2(s) < 0)
return -1;
// FIXME maybe move to end
if ((s->flags & CODEC_FLAG_PASS2) && s->avctx->rc_strategy == FF_RC_STRATEGY_XVID) {
#if CONFIG_LIBXVID
return ff_xvid_rate_control_init(s);
#else
av_log(s->avctx, AV_LOG_ERROR,
"Xvid ratecontrol requires libavcodec compiled with Xvid support.\n");
return -1;
#endif
}
}
if (!(s->flags & CODEC_FLAG_PASS2)) {
rcc->short_term_qsum = 0.001;
rcc->short_term_qcount = 0.001;
rcc->pass1_rc_eq_output_sum = 0.001;
rcc->pass1_wanted_bits = 0.001;
if (s->avctx->qblur > 1.0) {
av_log(s->avctx, AV_LOG_ERROR, "qblur too large\n");
return -1;
}
/* init stuff with the user specified complexity */
if (s->avctx->rc_initial_cplx) {
for (i = 0; i < 60 * 30; i++) {
double bits = s->avctx->rc_initial_cplx * (i / 10000.0 + 1.0) * s->mb_num;
RateControlEntry rce;
if (i % ((s->gop_size + 3) / 4) == 0)
rce.pict_type = AV_PICTURE_TYPE_I;
else if (i % (s->max_b_frames + 1))
rce.pict_type = AV_PICTURE_TYPE_B;
else
rce.pict_type = AV_PICTURE_TYPE_P;
rce.new_pict_type = rce.pict_type;
rce.mc_mb_var_sum = bits * s->mb_num / 100000;
rce.mb_var_sum = s->mb_num;
rce.qscale = FF_QP2LAMBDA * 2;
rce.f_code = 2;
rce.b_code = 1;
rce.misc_bits = 1;
if (s->pict_type == AV_PICTURE_TYPE_I) {
rce.i_count = s->mb_num;
rce.i_tex_bits = bits;
rce.p_tex_bits = 0;
rce.mv_bits = 0;
} else {
rce.i_count = 0; // FIXME we do know this approx
rce.i_tex_bits = 0;
rce.p_tex_bits = bits * 0.9;
rce.mv_bits = bits * 0.1;
}
rcc->i_cplx_sum[rce.pict_type] += rce.i_tex_bits * rce.qscale;
rcc->p_cplx_sum[rce.pict_type] += rce.p_tex_bits * rce.qscale;
rcc->mv_bits_sum[rce.pict_type] += rce.mv_bits;
rcc->frame_count[rce.pict_type]++;
get_qscale(s, &rce, rcc->pass1_wanted_bits / rcc->pass1_rc_eq_output_sum, i);
// FIXME misbehaves a little for variable fps
rcc->pass1_wanted_bits += s->bit_rate / (1 / av_q2d(s->avctx->time_base));
}
}
}
return 0;
}
av_cold void ff_rate_control_uninit(MpegEncContext *s)
{
RateControlContext *rcc = &s->rc_context;
emms_c();
av_expr_free(rcc->rc_eq_eval);
av_freep(&rcc->entry);
#if CONFIG_LIBXVID
if ((s->flags & CODEC_FLAG_PASS2) && s->avctx->rc_strategy == FF_RC_STRATEGY_XVID)
ff_xvid_rate_control_uninit(s);
#endif
}
int ff_vbv_update(MpegEncContext *s, int frame_size)
{
RateControlContext *rcc = &s->rc_context;
const double fps = 1 / av_q2d(s->avctx->time_base);
const int buffer_size = s->avctx->rc_buffer_size;
const double min_rate = s->avctx->rc_min_rate / fps;
const double max_rate = s->avctx->rc_max_rate / fps;
av_dlog(s, "%d %f %d %f %f\n",
buffer_size, rcc->buffer_index, frame_size, min_rate, max_rate);
if (buffer_size) {
int left;
rcc->buffer_index -= frame_size;
if (rcc->buffer_index < 0) {
av_log(s->avctx, AV_LOG_ERROR, "rc buffer underflow\n");
rcc->buffer_index = 0;
}
left = buffer_size - rcc->buffer_index - 1;
rcc->buffer_index += av_clip(left, min_rate, max_rate);
if (rcc->buffer_index > buffer_size) {
int stuffing = ceil((rcc->buffer_index - buffer_size) / 8);
if (stuffing < 4 && s->codec_id == AV_CODEC_ID_MPEG4)
stuffing = 4;
rcc->buffer_index -= 8 * stuffing;
if (s->avctx->debug & FF_DEBUG_RC)
av_log(s->avctx, AV_LOG_DEBUG, "stuffing %d bytes\n", stuffing);
return stuffing;
}
}
return 0;
}
/**
* Modify the bitrate curve from pass1 for one frame.
*/
static double get_qscale(MpegEncContext *s, RateControlEntry *rce,
double rate_factor, int frame_num)
{
RateControlContext *rcc = &s->rc_context;
AVCodecContext *a = s->avctx;
const int pict_type = rce->new_pict_type;
const double mb_num = s->mb_num;
double q, bits;
int i;
double const_values[] = {
M_PI,
M_E,
rce->i_tex_bits * rce->qscale,
rce->p_tex_bits * rce->qscale,
(rce->i_tex_bits + rce->p_tex_bits) * (double)rce->qscale,
rce->mv_bits / mb_num,
rce->pict_type == AV_PICTURE_TYPE_B ? (rce->f_code + rce->b_code) * 0.5 : rce->f_code,
rce->i_count / mb_num,
rce->mc_mb_var_sum / mb_num,
rce->mb_var_sum / mb_num,
rce->pict_type == AV_PICTURE_TYPE_I,
rce->pict_type == AV_PICTURE_TYPE_P,
rce->pict_type == AV_PICTURE_TYPE_B,
rcc->qscale_sum[pict_type] / (double)rcc->frame_count[pict_type],
a->qcompress,
#if 0
rcc->last_qscale_for[AV_PICTURE_TYPE_I],
rcc->last_qscale_for[AV_PICTURE_TYPE_P],
rcc->last_qscale_for[AV_PICTURE_TYPE_B],
rcc->next_non_b_qscale,
#endif
rcc->i_cplx_sum[AV_PICTURE_TYPE_I] / (double)rcc->frame_count[AV_PICTURE_TYPE_I],
rcc->i_cplx_sum[AV_PICTURE_TYPE_P] / (double)rcc->frame_count[AV_PICTURE_TYPE_P],
rcc->p_cplx_sum[AV_PICTURE_TYPE_P] / (double)rcc->frame_count[AV_PICTURE_TYPE_P],
rcc->p_cplx_sum[AV_PICTURE_TYPE_B] / (double)rcc->frame_count[AV_PICTURE_TYPE_B],
(rcc->i_cplx_sum[pict_type] + rcc->p_cplx_sum[pict_type]) / (double)rcc->frame_count[pict_type],
0
};
bits = av_expr_eval(rcc->rc_eq_eval, const_values, rce);
if (isnan(bits)) {
av_log(s->avctx, AV_LOG_ERROR, "Error evaluating rc_eq \"%s\"\n", s->avctx->rc_eq);
return -1;
}
rcc->pass1_rc_eq_output_sum += bits;
bits *= rate_factor;
if (bits < 0.0)
bits = 0.0;
bits += 1.0; // avoid 1/0 issues
/* user override */
for (i = 0; i < s->avctx->rc_override_count; i++) {
RcOverride *rco = s->avctx->rc_override;
if (rco[i].start_frame > frame_num)
continue;
if (rco[i].end_frame < frame_num)
continue;
if (rco[i].qscale)
bits = qp2bits(rce, rco[i].qscale); // FIXME move at end to really force it?
else
bits *= rco[i].quality_factor;
}
q = bits2qp(rce, bits);
/* I/B difference */
if (pict_type == AV_PICTURE_TYPE_I && s->avctx->i_quant_factor < 0.0)
q = -q * s->avctx->i_quant_factor + s->avctx->i_quant_offset;
else if (pict_type == AV_PICTURE_TYPE_B && s->avctx->b_quant_factor < 0.0)
q = -q * s->avctx->b_quant_factor + s->avctx->b_quant_offset;
if (q < 1)
q = 1;
return q;
}
static double get_diff_limited_q(MpegEncContext *s, RateControlEntry *rce, double q)
{
RateControlContext *rcc = &s->rc_context;
AVCodecContext *a = s->avctx;
const int pict_type = rce->new_pict_type;
const double last_p_q = rcc->last_qscale_for[AV_PICTURE_TYPE_P];
const double last_non_b_q = rcc->last_qscale_for[rcc->last_non_b_pict_type];
if (pict_type == AV_PICTURE_TYPE_I &&
(a->i_quant_factor > 0.0 || rcc->last_non_b_pict_type == AV_PICTURE_TYPE_P))
q = last_p_q * FFABS(a->i_quant_factor) + a->i_quant_offset;
else if (pict_type == AV_PICTURE_TYPE_B &&
a->b_quant_factor > 0.0)
q = last_non_b_q * a->b_quant_factor + a->b_quant_offset;
if (q < 1)
q = 1;
/* last qscale / qdiff stuff */
if (rcc->last_non_b_pict_type == pict_type || pict_type != AV_PICTURE_TYPE_I) {
double last_q = rcc->last_qscale_for[pict_type];
const int maxdiff = FF_QP2LAMBDA * a->max_qdiff;
if (q > last_q + maxdiff)
q = last_q + maxdiff;
else if (q < last_q - maxdiff)
q = last_q - maxdiff;
}
rcc->last_qscale_for[pict_type] = q; // Note we cannot do that after blurring
if (pict_type != AV_PICTURE_TYPE_B)
rcc->last_non_b_pict_type = pict_type;
return q;
}
/**
* Get the qmin & qmax for pict_type.
*/
static void get_qminmax(int *qmin_ret, int *qmax_ret, MpegEncContext *s, int pict_type)
{
int qmin = s->avctx->lmin;
int qmax = s->avctx->lmax;
assert(qmin <= qmax);
switch (pict_type) {
case AV_PICTURE_TYPE_B:
qmin = (int)(qmin * FFABS(s->avctx->b_quant_factor) + s->avctx->b_quant_offset + 0.5);
qmax = (int)(qmax * FFABS(s->avctx->b_quant_factor) + s->avctx->b_quant_offset + 0.5);
break;
case AV_PICTURE_TYPE_I:
qmin = (int)(qmin * FFABS(s->avctx->i_quant_factor) + s->avctx->i_quant_offset + 0.5);
qmax = (int)(qmax * FFABS(s->avctx->i_quant_factor) + s->avctx->i_quant_offset + 0.5);
break;
}
qmin = av_clip(qmin, 1, FF_LAMBDA_MAX);
qmax = av_clip(qmax, 1, FF_LAMBDA_MAX);
if (qmax < qmin)
qmax = qmin;
*qmin_ret = qmin;
*qmax_ret = qmax;
}
static double modify_qscale(MpegEncContext *s, RateControlEntry *rce,
double q, int frame_num)
{
RateControlContext *rcc = &s->rc_context;
const double buffer_size = s->avctx->rc_buffer_size;
const double fps = 1 / av_q2d(s->avctx->time_base);
const double min_rate = s->avctx->rc_min_rate / fps;
const double max_rate = s->avctx->rc_max_rate / fps;
const int pict_type = rce->new_pict_type;
int qmin, qmax;
get_qminmax(&qmin, &qmax, s, pict_type);
/* modulation */
if (s->avctx->rc_qmod_freq &&
frame_num % s->avctx->rc_qmod_freq == 0 &&
pict_type == AV_PICTURE_TYPE_P)
q *= s->avctx->rc_qmod_amp;
/* buffer overflow/underflow protection */
if (buffer_size) {
double expected_size = rcc->buffer_index;
double q_limit;
if (min_rate) {
double d = 2 * (buffer_size - expected_size) / buffer_size;
if (d > 1.0)
d = 1.0;
else if (d < 0.0001)
d = 0.0001;
q *= pow(d, 1.0 / s->avctx->rc_buffer_aggressivity);
q_limit = bits2qp(rce,
FFMAX((min_rate - buffer_size + rcc->buffer_index) *
s->avctx->rc_min_vbv_overflow_use, 1));
if (q > q_limit) {
if (s->avctx->debug & FF_DEBUG_RC)
av_log(s->avctx, AV_LOG_DEBUG,
"limiting QP %f -> %f\n", q, q_limit);
q = q_limit;
}
}
if (max_rate) {
double d = 2 * expected_size / buffer_size;
if (d > 1.0)
d = 1.0;
else if (d < 0.0001)
d = 0.0001;
q /= pow(d, 1.0 / s->avctx->rc_buffer_aggressivity);
q_limit = bits2qp(rce,
FFMAX(rcc->buffer_index *
s->avctx->rc_max_available_vbv_use,
1));
if (q < q_limit) {
if (s->avctx->debug & FF_DEBUG_RC)
av_log(s->avctx, AV_LOG_DEBUG,
"limiting QP %f -> %f\n", q, q_limit);
q = q_limit;
}
}
}
av_dlog(s, "q:%f max:%f min:%f size:%f index:%f agr:%f\n",
q, max_rate, min_rate, buffer_size, rcc->buffer_index,
s->avctx->rc_buffer_aggressivity);
if (s->avctx->rc_qsquish == 0.0 || qmin == qmax) {
if (q < qmin)
q = qmin;
else if (q > qmax)
q = qmax;
} else {
double min2 = log(qmin);
double max2 = log(qmax);
q = log(q);
q = (q - min2) / (max2 - min2) - 0.5;
q *= -4.0;
q = 1.0 / (1.0 + exp(q));
q = q * (max2 - min2) + min2;
q = exp(q);
}
return q;
}
// ----------------------------------
// 1 Pass Code
static double predict_size(Predictor *p, double q, double var)
{
return p->coeff * var / (q * p->count);
}
static void update_predictor(Predictor *p, double q, double var, double size)
{
double new_coeff = size * q / (var + 1);
if (var < 10)
return;
p->count *= p->decay;
p->coeff *= p->decay;
p->count++;
p->coeff += new_coeff;
}
static void adaptive_quantization(MpegEncContext *s, double q)
{
int i;
const float lumi_masking = s->avctx->lumi_masking / (128.0 * 128.0);
const float dark_masking = s->avctx->dark_masking / (128.0 * 128.0);
const float temp_cplx_masking = s->avctx->temporal_cplx_masking;
const float spatial_cplx_masking = s->avctx->spatial_cplx_masking;
const float p_masking = s->avctx->p_masking;
const float border_masking = s->avctx->border_masking;
float bits_sum = 0.0;
float cplx_sum = 0.0;
float *cplx_tab = s->cplx_tab;
float *bits_tab = s->bits_tab;
const int qmin = s->avctx->mb_lmin;
const int qmax = s->avctx->mb_lmax;
Picture *const pic = &s->current_picture;
const int mb_width = s->mb_width;
const int mb_height = s->mb_height;
for (i = 0; i < s->mb_num; i++) {
const int mb_xy = s->mb_index2xy[i];
float temp_cplx = sqrt(pic->mc_mb_var[mb_xy]); // FIXME merge in pow()
float spat_cplx = sqrt(pic->mb_var[mb_xy]);
const int lumi = pic->mb_mean[mb_xy];
float bits, cplx, factor;
int mb_x = mb_xy % s->mb_stride;
int mb_y = mb_xy / s->mb_stride;
int mb_distance;
float mb_factor = 0.0;
if (spat_cplx < 4)
spat_cplx = 4; // FIXME finetune
if (temp_cplx < 4)
temp_cplx = 4; // FIXME finetune
if ((s->mb_type[mb_xy] & CANDIDATE_MB_TYPE_INTRA)) { // FIXME hq mode
cplx = spat_cplx;
factor = 1.0 + p_masking;
} else {
cplx = temp_cplx;
factor = pow(temp_cplx, -temp_cplx_masking);
}
factor *= pow(spat_cplx, -spatial_cplx_masking);
if (lumi > 127)
factor *= (1.0 - (lumi - 128) * (lumi - 128) * lumi_masking);
else
factor *= (1.0 - (lumi - 128) * (lumi - 128) * dark_masking);
if (mb_x < mb_width / 5) {
mb_distance = mb_width / 5 - mb_x;
mb_factor = (float)mb_distance / (float)(mb_width / 5);
} else if (mb_x > 4 * mb_width / 5) {
mb_distance = mb_x - 4 * mb_width / 5;
mb_factor = (float)mb_distance / (float)(mb_width / 5);
}
if (mb_y < mb_height / 5) {
mb_distance = mb_height / 5 - mb_y;
mb_factor = FFMAX(mb_factor,
(float)mb_distance / (float)(mb_height / 5));
} else if (mb_y > 4 * mb_height / 5) {
mb_distance = mb_y - 4 * mb_height / 5;
mb_factor = FFMAX(mb_factor,
(float)mb_distance / (float)(mb_height / 5));
}
factor *= 1.0 - border_masking * mb_factor;
if (factor < 0.00001)
factor = 0.00001;
bits = cplx * factor;
cplx_sum += cplx;
bits_sum += bits;
cplx_tab[i] = cplx;
bits_tab[i] = bits;
}
/* handle qmin/qmax clipping */
if (s->flags & CODEC_FLAG_NORMALIZE_AQP) {
float factor = bits_sum / cplx_sum;
for (i = 0; i < s->mb_num; i++) {
float newq = q * cplx_tab[i] / bits_tab[i];
newq *= factor;
if (newq > qmax) {
bits_sum -= bits_tab[i];
cplx_sum -= cplx_tab[i] * q / qmax;
} else if (newq < qmin) {
bits_sum -= bits_tab[i];
cplx_sum -= cplx_tab[i] * q / qmin;
}
}
if (bits_sum < 0.001)
bits_sum = 0.001;
if (cplx_sum < 0.001)
cplx_sum = 0.001;
}
for (i = 0; i < s->mb_num; i++) {
const int mb_xy = s->mb_index2xy[i];
float newq = q * cplx_tab[i] / bits_tab[i];
int intq;
if (s->flags & CODEC_FLAG_NORMALIZE_AQP) {
newq *= bits_sum / cplx_sum;
}
intq = (int)(newq + 0.5);
if (intq > qmax)
intq = qmax;
else if (intq < qmin)
intq = qmin;
s->lambda_table[mb_xy] = intq;
}
}
void ff_get_2pass_fcode(MpegEncContext *s)
{
RateControlContext *rcc = &s->rc_context;
RateControlEntry *rce = &rcc->entry[s->picture_number];
s->f_code = rce->f_code;
s->b_code = rce->b_code;
}
// FIXME rd or at least approx for dquant
float ff_rate_estimate_qscale(MpegEncContext *s, int dry_run)
{
float q;
int qmin, qmax;
float br_compensation;
double diff;
double short_term_q;
double fps;
int picture_number = s->picture_number;
int64_t wanted_bits;
RateControlContext *rcc = &s->rc_context;
AVCodecContext *a = s->avctx;
RateControlEntry local_rce, *rce;
double bits;
double rate_factor;
int var;
const int pict_type = s->pict_type;
Picture * const pic = &s->current_picture;
emms_c();
#if CONFIG_LIBXVID
if ((s->flags & CODEC_FLAG_PASS2) &&
s->avctx->rc_strategy == FF_RC_STRATEGY_XVID)
return ff_xvid_rate_estimate_qscale(s, dry_run);
#endif
get_qminmax(&qmin, &qmax, s, pict_type);
fps = 1 / av_q2d(s->avctx->time_base);
/* update predictors */
if (picture_number > 2 && !dry_run) {
const int last_var = s->last_pict_type == AV_PICTURE_TYPE_I ? rcc->last_mb_var_sum
: rcc->last_mc_mb_var_sum;
update_predictor(&rcc->pred[s->last_pict_type],
rcc->last_qscale,
sqrt(last_var), s->frame_bits);
}
if (s->flags & CODEC_FLAG_PASS2) {
assert(picture_number >= 0);
assert(picture_number < rcc->num_entries);
rce = &rcc->entry[picture_number];
wanted_bits = rce->expected_bits;
} else {
Picture *dts_pic;
rce = &local_rce;
/* FIXME add a dts field to AVFrame and ensure it is set and use it
* here instead of reordering but the reordering is simpler for now
* until H.264 B-pyramid must be handled. */
if (s->pict_type == AV_PICTURE_TYPE_B || s->low_delay)
dts_pic = s->current_picture_ptr;
else
dts_pic = s->last_picture_ptr;
if (!dts_pic || dts_pic->f.pts == AV_NOPTS_VALUE)
wanted_bits = (uint64_t)(s->bit_rate * (double)picture_number / fps);
else
wanted_bits = (uint64_t)(s->bit_rate * (double)dts_pic->f.pts / fps);
}
diff = s->total_bits - wanted_bits;
br_compensation = (a->bit_rate_tolerance - diff) / a->bit_rate_tolerance;
if (br_compensation <= 0.0)
br_compensation = 0.001;
var = pict_type == AV_PICTURE_TYPE_I ? pic->mb_var_sum : pic->mc_mb_var_sum;
short_term_q = 0; /* avoid warning */
if (s->flags & CODEC_FLAG_PASS2) {
if (pict_type != AV_PICTURE_TYPE_I)
assert(pict_type == rce->new_pict_type);
q = rce->new_qscale / br_compensation;
av_dlog(s, "%f %f %f last:%d var:%d type:%d//\n", q, rce->new_qscale,
br_compensation, s->frame_bits, var, pict_type);
} else {
rce->pict_type =
rce->new_pict_type = pict_type;
rce->mc_mb_var_sum = pic->mc_mb_var_sum;
rce->mb_var_sum = pic->mb_var_sum;
rce->qscale = FF_QP2LAMBDA * 2;
rce->f_code = s->f_code;
rce->b_code = s->b_code;
rce->misc_bits = 1;
bits = predict_size(&rcc->pred[pict_type], rce->qscale, sqrt(var));
if (pict_type == AV_PICTURE_TYPE_I) {
rce->i_count = s->mb_num;
rce->i_tex_bits = bits;
rce->p_tex_bits = 0;
rce->mv_bits = 0;
} else {
rce->i_count = 0; // FIXME we do know this approx
rce->i_tex_bits = 0;
rce->p_tex_bits = bits * 0.9;
rce->mv_bits = bits * 0.1;
}
rcc->i_cplx_sum[pict_type] += rce->i_tex_bits * rce->qscale;
rcc->p_cplx_sum[pict_type] += rce->p_tex_bits * rce->qscale;
rcc->mv_bits_sum[pict_type] += rce->mv_bits;
rcc->frame_count[pict_type]++;
bits = rce->i_tex_bits + rce->p_tex_bits;
rate_factor = rcc->pass1_wanted_bits /
rcc->pass1_rc_eq_output_sum * br_compensation;
q = get_qscale(s, rce, rate_factor, picture_number);
if (q < 0)
return -1;
assert(q > 0.0);
q = get_diff_limited_q(s, rce, q);
assert(q > 0.0);
// FIXME type dependent blur like in 2-pass
if (pict_type == AV_PICTURE_TYPE_P || s->intra_only) {
rcc->short_term_qsum *= a->qblur;
rcc->short_term_qcount *= a->qblur;
rcc->short_term_qsum += q;
rcc->short_term_qcount++;
q = short_term_q = rcc->short_term_qsum / rcc->short_term_qcount;
}
assert(q > 0.0);
q = modify_qscale(s, rce, q, picture_number);
rcc->pass1_wanted_bits += s->bit_rate / fps;
assert(q > 0.0);
}
if (s->avctx->debug & FF_DEBUG_RC) {
av_log(s->avctx, AV_LOG_DEBUG,
"%c qp:%d<%2.1f<%d %d want:%d total:%d comp:%f st_q:%2.2f "
"size:%d var:%d/%d br:%d fps:%d\n",
av_get_picture_type_char(pict_type),
qmin, q, qmax, picture_number,
(int)wanted_bits / 1000, (int)s->total_bits / 1000,
br_compensation, short_term_q, s->frame_bits,
pic->mb_var_sum, pic->mc_mb_var_sum,
s->bit_rate / 1000, (int)fps);
}
if (q < qmin)
q = qmin;
else if (q > qmax)
q = qmax;
if (s->adaptive_quant)
adaptive_quantization(s, q);
else
q = (int)(q + 0.5);
if (!dry_run) {
rcc->last_qscale = q;
rcc->last_mc_mb_var_sum = pic->mc_mb_var_sum;
rcc->last_mb_var_sum = pic->mb_var_sum;
}
return q;
}
// ----------------------------------------------
// 2-Pass code
static int init_pass2(MpegEncContext *s)
{
RateControlContext *rcc = &s->rc_context;
AVCodecContext *a = s->avctx;
int i, toobig;
double fps = 1 / av_q2d(s->avctx->time_base);
double complexity[5] = { 0 }; // approximate bits at quant=1
uint64_t const_bits[5] = { 0 }; // quantizer independent bits
uint64_t all_const_bits;
uint64_t all_available_bits = (uint64_t)(s->bit_rate *
(double)rcc->num_entries / fps);
double rate_factor = 0;
double step;
const int filter_size = (int)(a->qblur * 4) | 1;
double expected_bits;
double *qscale, *blurred_qscale, qscale_sum;
/* find complexity & const_bits & decide the pict_types */
for (i = 0; i < rcc->num_entries; i++) {
RateControlEntry *rce = &rcc->entry[i];
rce->new_pict_type = rce->pict_type;
rcc->i_cplx_sum[rce->pict_type] += rce->i_tex_bits * rce->qscale;
rcc->p_cplx_sum[rce->pict_type] += rce->p_tex_bits * rce->qscale;
rcc->mv_bits_sum[rce->pict_type] += rce->mv_bits;
rcc->frame_count[rce->pict_type]++;
complexity[rce->new_pict_type] += (rce->i_tex_bits + rce->p_tex_bits) *
(double)rce->qscale;
const_bits[rce->new_pict_type] += rce->mv_bits + rce->misc_bits;
}
all_const_bits = const_bits[AV_PICTURE_TYPE_I] +
const_bits[AV_PICTURE_TYPE_P] +
const_bits[AV_PICTURE_TYPE_B];
if (all_available_bits < all_const_bits) {
av_log(s->avctx, AV_LOG_ERROR, "requested bitrate is too low\n");
return -1;
}
qscale = av_malloc(sizeof(double) * rcc->num_entries);
blurred_qscale = av_malloc(sizeof(double) * rcc->num_entries);
toobig = 0;
for (step = 256 * 256; step > 0.0000001; step *= 0.5) {
expected_bits = 0;
rate_factor += step;
rcc->buffer_index = s->avctx->rc_buffer_size / 2;
/* find qscale */
for (i = 0; i < rcc->num_entries; i++) {
RateControlEntry *rce = &rcc->entry[i];
qscale[i] = get_qscale(s, &rcc->entry[i], rate_factor, i);
rcc->last_qscale_for[rce->pict_type] = qscale[i];
}
assert(filter_size % 2 == 1);
/* fixed I/B QP relative to P mode */
for (i = rcc->num_entries - 1; i >= 0; i--) {
RateControlEntry *rce = &rcc->entry[i];
qscale[i] = get_diff_limited_q(s, rce, qscale[i]);
}
/* smooth curve */
for (i = 0; i < rcc->num_entries; i++) {
RateControlEntry *rce = &rcc->entry[i];
const int pict_type = rce->new_pict_type;
int j;
double q = 0.0, sum = 0.0;
for (j = 0; j < filter_size; j++) {
int index = i + j - filter_size / 2;
double d = index - i;
double coeff = a->qblur == 0 ? 1.0 : exp(-d * d / (a->qblur * a->qblur));
if (index < 0 || index >= rcc->num_entries)
continue;
if (pict_type != rcc->entry[index].new_pict_type)
continue;
q += qscale[index] * coeff;
sum += coeff;
}
blurred_qscale[i] = q / sum;
}
/* find expected bits */
for (i = 0; i < rcc->num_entries; i++) {
RateControlEntry *rce = &rcc->entry[i];
double bits;
rce->new_qscale = modify_qscale(s, rce, blurred_qscale[i], i);
bits = qp2bits(rce, rce->new_qscale) + rce->mv_bits + rce->misc_bits;
bits += 8 * ff_vbv_update(s, bits);
rce->expected_bits = expected_bits;
expected_bits += bits;
}
av_dlog(s->avctx,
"expected_bits: %f all_available_bits: %d rate_factor: %f\n",
expected_bits, (int)all_available_bits, rate_factor);
if (expected_bits > all_available_bits) {
rate_factor -= step;
++toobig;
}
}
av_free(qscale);
av_free(blurred_qscale);
/* check bitrate calculations and print info */
qscale_sum = 0.0;
for (i = 0; i < rcc->num_entries; i++) {
av_dlog(s, "[lavc rc] entry[%d].new_qscale = %.3f qp = %.3f\n",
i,
rcc->entry[i].new_qscale,
rcc->entry[i].new_qscale / FF_QP2LAMBDA);
qscale_sum += av_clip(rcc->entry[i].new_qscale / FF_QP2LAMBDA,
s->avctx->qmin, s->avctx->qmax);
}
assert(toobig <= 40);
av_log(s->avctx, AV_LOG_DEBUG,
"[lavc rc] requested bitrate: %d bps expected bitrate: %d bps\n",
s->bit_rate,
(int)(expected_bits / ((double)all_available_bits / s->bit_rate)));
av_log(s->avctx, AV_LOG_DEBUG,
"[lavc rc] estimated target average qp: %.3f\n",
(float)qscale_sum / rcc->num_entries);
if (toobig == 0) {
av_log(s->avctx, AV_LOG_INFO,
"[lavc rc] Using all of requested bitrate is not "
"necessary for this video with these parameters.\n");
} else if (toobig == 40) {
av_log(s->avctx, AV_LOG_ERROR,
"[lavc rc] Error: bitrate too low for this video "
"with these parameters.\n");
return -1;
} else if (fabs(expected_bits / all_available_bits - 1.0) > 0.01) {
av_log(s->avctx, AV_LOG_ERROR,
"[lavc rc] Error: 2pass curve failed to converge\n");
return -1;
}
return 0;
}