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]={0,0,0,0,0}; // aproximate bits at quant=1
uint64_t const_bits[5]={0,0,0,0,0}; // 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;
//int last_i_frame=-10000000;
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[FF_I_TYPE] + const_bits[FF_P_TYPE] + const_bits[FF_B_TYPE];
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++){
qscale[i]= get_qscale(s, &rcc->entry[i], rate_factor, 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;
//printf("%d %f\n", rce->new_bits, blurred_qscale[i]);
bits += 8*ff_vbv_update(s, bits);
rce->expected_bits= expected_bits;
expected_bits += bits;
}
/*
av_log(s->avctx, AV_LOG_INFO,
"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_log(s->avctx, AV_LOG_DEBUG, "[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;
}
static int init_pass2(MpegEncContext *s)
{
RateControlContext *rcc= &s->rc_context;
AVCodecContext *a= s->avctx;
int i;
double fps= (double)s->avctx->frame_rate / (double)s->avctx->frame_rate_base;
double complexity[5]={0,0,0,0,0}; // aproximate bits at quant=1
double avg_quantizer[5];
uint64_t const_bits[5]={0,0,0,0,0}; // quantizer idependant bits
uint64_t available_bits[5];
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;
//int last_i_frame=-10000000;
const int filter_size= (int)(a->qblur*4) | 1;
double expected_bits;
double *qscale, *blured_qscale;
/* 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[I_TYPE] + const_bits[P_TYPE] + const_bits[B_TYPE];
if(all_available_bits < all_const_bits){
av_log(s->avctx, AV_LOG_ERROR, "requested bitrate is to low\n");
return -1;
}
/* find average quantizers */
avg_quantizer[P_TYPE]=0;
for(step=256*256; step>0.0000001; step*=0.5){
double expected_bits=0;
avg_quantizer[P_TYPE]+= step;
avg_quantizer[I_TYPE]= avg_quantizer[P_TYPE]*ABS(s->avctx->i_quant_factor) + s->avctx->i_quant_offset;
avg_quantizer[B_TYPE]= avg_quantizer[P_TYPE]*ABS(s->avctx->b_quant_factor) + s->avctx->b_quant_offset;
expected_bits=
+ all_const_bits
+ complexity[I_TYPE]/avg_quantizer[I_TYPE]
+ complexity[P_TYPE]/avg_quantizer[P_TYPE]
+ complexity[B_TYPE]/avg_quantizer[B_TYPE];
if(expected_bits < all_available_bits) avg_quantizer[P_TYPE]-= step;
//printf("%f %lld %f\n", expected_bits, all_available_bits, avg_quantizer[P_TYPE]);
}
//printf("qp_i:%f, qp_p:%f, qp_b:%f\n", avg_quantizer[I_TYPE],avg_quantizer[P_TYPE],avg_quantizer[B_TYPE]);
for(i=0; i<5; i++){
available_bits[i]= const_bits[i] + complexity[i]/avg_quantizer[i];
}
//printf("%lld %lld %lld %lld\n", available_bits[I_TYPE], available_bits[P_TYPE], available_bits[B_TYPE], all_available_bits);
qscale= av_malloc(sizeof(double)*rcc->num_entries);
blured_qscale= av_malloc(sizeof(double)*rcc->num_entries);
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++){
qscale[i]= get_qscale(s, &rcc->entry[i], rate_factor, 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;
}
blured_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, blured_qscale[i], i);
bits= qp2bits(rce, rce->new_qscale) + rce->mv_bits + rce->misc_bits;
//printf("%d %f\n", rce->new_bits, blured_qscale[i]);
bits += 8*ff_vbv_update(s, bits);
rce->expected_bits= expected_bits;
expected_bits += bits;
}
// printf("%f %d %f\n", expected_bits, (int)all_available_bits, rate_factor);
if(expected_bits > all_available_bits) rate_factor-= step;
}
av_free(qscale);
av_free(blured_qscale);
if(abs(expected_bits/all_available_bits - 1.0) > 0.01 ){
av_log(s->avctx, AV_LOG_ERROR, "Error: 2pass curve failed to converge\n");
return -1;
}
return 0;
}
