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ratecontrol: Reorder functions to avoid forward declarations

tags/n3.3
Vittorio Giovara 9 years ago
parent
d639dcdae0
commit
a1f6a2dfda
1 changed files with 430 additions and 440 deletions
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  1. +430
    -440
      libavcodec/ratecontrol.c

+ 430
- 440
libavcodec/ratecontrol.c View File

@@ -42,24 +42,406 @@
#define M_E 2.718281828 #define M_E 2.718281828
#endif #endif


static int init_pass2(MpegEncContext *s);
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;
}

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->lmin;
int qmax = s->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->rc_qmod_freq &&
frame_num % s->rc_qmod_freq == 0 &&
pict_type == AV_PICTURE_TYPE_P)
q *= s->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->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->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;
}
}
}
ff_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->rc_buffer_aggressivity);
if (s->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;
}

/**
* Modify the bitrate curve from pass1 for one frame.
*/
static double get_qscale(MpegEncContext *s, RateControlEntry *rce, static double get_qscale(MpegEncContext *s, RateControlEntry *rce,
double rate_factor, int frame_num);
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,
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->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 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);
if (!qscale || !blurred_qscale) {
av_free(qscale);
av_free(blurred_qscale);
return AVERROR(ENOMEM);
}
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;
}


static inline double qp2bits(RateControlEntry *rce, double qp)
{
if (qp <= 0.0) {
av_log(NULL, AV_LOG_ERROR, "qp<=0.0\n");
ff_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;
}
} }
return rce->qscale * (double)(rce->i_tex_bits + rce->p_tex_bits + 1) / qp;
}
av_free(qscale);
av_free(blurred_qscale);


static inline double bits2qp(RateControlEntry *rce, double bits)
{
if (bits < 0.9) {
av_log(NULL, AV_LOG_ERROR, "bits<0.9\n");
/* check bitrate calculations and print info */
qscale_sum = 0.0;
for (i = 0; i < rcc->num_entries; i++) {
ff_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);
} }
return rce->qscale * (double)(rce->i_tex_bits + rce->p_tex_bits + 1) / bits;
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;
} }


av_cold int ff_rate_control_init(MpegEncContext *s) av_cold int ff_rate_control_init(MpegEncContext *s)
@@ -253,288 +635,54 @@ av_cold int ff_rate_control_init(MpegEncContext *s)
return 0; 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);
}

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;

ff_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,
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->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->lmin;
int qmax = s->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);
av_cold void ff_rate_control_uninit(MpegEncContext *s)
{
RateControlContext *rcc = &s->rc_context;
emms_c();


/* modulation */
if (s->rc_qmod_freq &&
frame_num % s->rc_qmod_freq == 0 &&
pict_type == AV_PICTURE_TYPE_P)
q *= s->rc_qmod_amp;
av_expr_free(rcc->rc_eq_eval);
av_freep(&rcc->entry);
}


/* buffer overflow/underflow protection */
if (buffer_size) {
double expected_size = rcc->buffer_index;
double q_limit;
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;


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->rc_buffer_aggressivity);
ff_dlog(s, "%d %f %d %f %f\n",
buffer_size, rcc->buffer_index, frame_size, min_rate, max_rate);


q_limit = bits2qp(rce,
FFMAX((min_rate - buffer_size + rcc->buffer_index) *
s->avctx->rc_min_vbv_overflow_use, 1));
if (buffer_size) {
int left;


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;
}
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;
} }


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->rc_buffer_aggressivity);
left = buffer_size - rcc->buffer_index - 1;
rcc->buffer_index += av_clip(left, min_rate, max_rate);


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;
}
}
}
ff_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->rc_buffer_aggressivity);
if (s->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);
if (rcc->buffer_index > buffer_size) {
int stuffing = ceil((rcc->buffer_index - buffer_size) / 8);


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;
if (stuffing < 4 && s->codec_id == AV_CODEC_ID_MPEG4)
stuffing = 4;
rcc->buffer_index -= 8 * stuffing;


q = exp(q);
}
if (s->avctx->debug & FF_DEBUG_RC)
av_log(s->avctx, AV_LOG_DEBUG, "stuffing %d bytes\n", stuffing);


return q;
return stuffing;
}
}
return 0;
} }


// ----------------------------------
// 1 Pass Code

static double predict_size(Predictor *p, double q, double var) static double predict_size(Predictor *p, double q, double var)
{ {
return p->coeff * var / (q * p->count); return p->coeff * var / (q * p->count);
@@ -836,161 +984,3 @@ float ff_rate_estimate_qscale(MpegEncContext *s, int dry_run)
} }
return q; 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);
if (!qscale || !blurred_qscale) {
av_free(qscale);
av_free(blurred_qscale);
return AVERROR(ENOMEM);
}
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;
}

ff_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++) {
ff_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;
}

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