35 |
/* forces second pass not to be bigger than first */ |
/* forces second pass not to be bigger than first */ |
36 |
#undef PASS_SMALLER |
#undef PASS_SMALLER |
37 |
|
|
38 |
|
/* automtically alters overflow controls (strength and improvement/degradation) |
39 |
|
to fight most common problems without user's knowladge */ |
40 |
|
#define SMART_OVERFLOW_SETTING |
41 |
|
|
42 |
#include <stdio.h> |
#include <stdio.h> |
43 |
#include <math.h> |
#include <math.h> |
44 |
#include <limits.h> |
#include <limits.h> |
134 |
|
|
135 |
/*---------------------------------- |
/*---------------------------------- |
136 |
* Zones statistical data |
* Zones statistical data |
|
* |
|
|
* ToDo: Fix zones, current |
|
|
* implementation is buggy |
|
137 |
*--------------------------------*/ |
*--------------------------------*/ |
138 |
|
|
|
/* Average weight of the zones */ |
|
|
double avg_weight; |
|
|
|
|
139 |
/* Total length used by XVID_ZONE_QUANT zones */ |
/* Total length used by XVID_ZONE_QUANT zones */ |
140 |
uint64_t tot_quant; |
uint64_t tot_quant; |
141 |
uint64_t tot_quant_invariant; |
uint64_t tot_quant_invariant; |
142 |
|
|
143 |
|
/* Holds the total amount of frame bytes, zone weighted (only scalable |
144 |
|
* part of frame bytes) */ |
145 |
|
uint64_t tot_weighted; |
146 |
|
|
147 |
/*---------------------------------- |
/*---------------------------------- |
148 |
* Advanced settings helper ratios |
* Advanced settings helper ratios |
149 |
*--------------------------------*/ |
*--------------------------------*/ |
177 |
twopass_stat_t * stats; |
twopass_stat_t * stats; |
178 |
|
|
179 |
/*---------------------------------- |
/*---------------------------------- |
180 |
* Histerysis helpers |
* Hysteresis helpers |
181 |
*--------------------------------*/ |
*--------------------------------*/ |
182 |
|
|
183 |
/* This field holds the int2float conversion errors of each quant per |
/* This field holds the int2float conversion errors of each quant per |
212 |
* ToDo: description */ |
* ToDo: description */ |
213 |
double fq_error; |
double fq_error; |
214 |
|
|
215 |
|
int min_quant; /* internal minimal quant, prevents wrong quants from being used */ |
216 |
|
|
217 |
/*---------------------------------- |
/*---------------------------------- |
218 |
* Debug |
* Debug |
219 |
*--------------------------------*/ |
*--------------------------------*/ |
270 |
static void first_pass_stats_prepare_data(rc_2pass2_t * rc); |
static void first_pass_stats_prepare_data(rc_2pass2_t * rc); |
271 |
static void first_pass_scale_curve_internal(rc_2pass2_t *rc); |
static void first_pass_scale_curve_internal(rc_2pass2_t *rc); |
272 |
static void scaled_curve_apply_advanced_parameters(rc_2pass2_t * rc); |
static void scaled_curve_apply_advanced_parameters(rc_2pass2_t * rc); |
273 |
|
#ifdef VBV |
274 |
|
static int check_curve_for_vbv_compliancy(rc_2pass2_t * rc, const float fps); |
275 |
|
static int scale_curve_for_vbv_compliancy(rc_2pass2_t * rc, const float fps); |
276 |
|
#endif |
277 |
|
|
278 |
#if 0 |
#if 0 |
279 |
static void stats_print(rc_2pass2_t * rc); |
static void stats_print(rc_2pass2_t * rc); |
280 |
#endif |
#endif |
322 |
for (i=0; i<3; i++) rc->last_quant[i] = 0; |
for (i=0; i<3; i++) rc->last_quant[i] = 0; |
323 |
|
|
324 |
rc->fq_error = 0; |
rc->fq_error = 0; |
325 |
|
rc->min_quant = 1; |
326 |
|
|
327 |
/* Count frames (and intra frames) in the stats file, store the result into |
/* Count frames (and intra frames) in the stats file, store the result into |
328 |
* the rc structure */ |
* the rc structure */ |
385 |
if(rc->param.container_frame_overhead) |
if(rc->param.container_frame_overhead) |
386 |
DPRINTF(XVID_DEBUG_RC, "[xvid rc] -- New target filesize after container compensation: %lld\n", rc->target); |
DPRINTF(XVID_DEBUG_RC, "[xvid rc] -- New target filesize after container compensation: %lld\n", rc->target); |
387 |
|
|
388 |
|
/* When bitrate is not given it means it has been scaled by an external |
389 |
|
* application */ |
390 |
|
if (rc->param.bitrate) { |
391 |
|
/* Apply zone settings |
392 |
|
* - set rc->tot_quant which represents the total num of bytes spent in |
393 |
|
* fixed quant zones |
394 |
|
* - set rc->tot_weighted which represents the total amount of bytes |
395 |
|
* spent in normal or weighted zones in first pass (normal zones can |
396 |
|
* be considered weight=1) |
397 |
|
* - set rc->tot_quant_invariant which represents the total num of bytes |
398 |
|
* spent in fixed quant zones for headers */ |
399 |
|
zone_process(rc, create); |
400 |
|
} else { |
401 |
|
/* External scaling -- zones are ignored */ |
402 |
|
for (i=0;i<rc->num_frames;i++) { |
403 |
|
rc->stats[i].zone_mode = XVID_ZONE_WEIGHT; |
404 |
|
rc->stats[i].weight = 1.0; |
405 |
|
} |
406 |
|
rc->tot_quant = 0; |
407 |
|
} |
408 |
|
|
409 |
/* Gathers some information about first pass stats: |
/* Gathers some information about first pass stats: |
410 |
* - finds the minimum frame length for each frame type during 1st pass. |
* - finds the minimum frame length for each frame type during 1st pass. |
411 |
* rc->min_size[] |
* rc->min_size[] |
421 |
*/ |
*/ |
422 |
first_pass_stats_prepare_data(rc); |
first_pass_stats_prepare_data(rc); |
423 |
|
|
424 |
/* When bitrate is not given it means it has been scaled by an external |
/* If we have a user bitrate, it means it's an internal curve scaling */ |
|
* application */ |
|
425 |
if (rc->param.bitrate) { |
if (rc->param.bitrate) { |
|
/* Apply zone settings |
|
|
* - set rc->tot_quant which represents the total num of bytes spent in |
|
|
* fixed quant zones |
|
|
* - set rc->tot_quant_invariant which represents the total num of bytes spent |
|
|
* in fixed quant zones for headers */ |
|
|
zone_process(rc, create); |
|
426 |
/* Perform internal curve scaling */ |
/* Perform internal curve scaling */ |
427 |
first_pass_scale_curve_internal(rc); |
first_pass_scale_curve_internal(rc); |
|
} else { |
|
|
/* External scaling -- zones are ignored */ |
|
|
for (i=0;i<rc->num_frames;i++) { |
|
|
rc->stats[i].zone_mode = XVID_ZONE_WEIGHT; |
|
|
rc->stats[i].weight = 1.0; |
|
|
} |
|
|
rc->avg_weight = 1.0; |
|
|
rc->tot_quant = 0; |
|
428 |
} |
} |
429 |
|
|
430 |
/* Apply advanced curve options, and compute some parameters in order to |
/* Apply advanced curve options, and compute some parameters in order to |
431 |
* shape the curve in the BEFORE/AFTER pair of functions */ |
* shape the curve in the BEFORE/AFTER pair of functions */ |
432 |
scaled_curve_apply_advanced_parameters(rc); |
scaled_curve_apply_advanced_parameters(rc); |
433 |
|
|
434 |
|
|
435 |
|
#ifdef VBV |
436 |
|
/* Check curve for VBV compliancy and rescale if necessary */ |
437 |
|
|
438 |
|
|
439 |
|
#ifdef VBV_FORCE |
440 |
|
if (rc->param.vbvsize==0) |
441 |
|
{ |
442 |
|
rc->param.vbvsize = 3145728; |
443 |
|
rc->param.vbvinitial = 2359296; |
444 |
|
rc->param.vbv_maxrate = 4000000; |
445 |
|
rc->param.vbv_peakrate = 10000000; |
446 |
|
} |
447 |
|
#endif |
448 |
|
|
449 |
|
if (rc->param.vbvsize>0) /* vbvsize==0 switches VBV check off */ |
450 |
|
{ |
451 |
|
const double fps = (double)create->fbase/(double)create->fincr; |
452 |
|
int status = check_curve_for_vbv_compliancy(rc, fps); |
453 |
|
#ifdef VBV_DEBUG |
454 |
|
if (status) |
455 |
|
fprintf(stderr,"underflow detected\n Scaling Curve for compliancy... "); |
456 |
|
#endif |
457 |
|
|
458 |
|
status = scale_curve_for_vbv_compliancy(rc, fps); |
459 |
|
|
460 |
|
#ifdef VBV_DEBUG |
461 |
|
if (status==0) |
462 |
|
fprintf(stderr,"done.\n"); |
463 |
|
else |
464 |
|
fprintf(stderr,"impossible.\n"); |
465 |
|
#endif |
466 |
|
} |
467 |
|
#endif |
468 |
|
|
469 |
*handle = rc; |
*handle = rc; |
470 |
return(0); |
return(0); |
471 |
} |
} |
664 |
#ifdef PASS_SMALLER |
#ifdef PASS_SMALLER |
665 |
if (dbytes > s->length) { |
if (dbytes > s->length) { |
666 |
dbytes = s->length; |
dbytes = s->length; |
667 |
} else |
} |
668 |
#endif |
#endif |
669 |
|
|
670 |
|
/* Prevent stupid desired sizes under logical values */ |
671 |
if (dbytes < rc->min_length[s->type-1]) { |
if (dbytes < rc->min_length[s->type-1]) { |
672 |
dbytes = rc->min_length[s->type-1]; |
dbytes = rc->min_length[s->type-1]; |
|
} else if (dbytes > rc->max_length) { |
|
|
/* ToDo: this condition is always wrong as max_length == maximum frame |
|
|
* length of first pass, so the first condition already caps the frame |
|
|
* size... */ |
|
|
capped_to_max_framesize = 1; |
|
|
dbytes = rc->max_length; |
|
|
DPRINTF(XVID_DEBUG_RC,"[xvid rc] -- frame:%d Capped to maximum frame size\n", |
|
|
data->frame_num); |
|
673 |
} |
} |
674 |
|
|
675 |
/*------------------------------------------------------------------------ |
/*------------------------------------------------------------------------ |
754 |
data->quant = data->max_quant[s->type-1]; |
data->quant = data->max_quant[s->type-1]; |
755 |
} |
} |
756 |
|
|
757 |
|
if (data->quant < rc->min_quant) data->quant = rc->min_quant; |
758 |
|
|
759 |
/* To avoid big quality jumps from frame to frame, we apply a "security" |
/* To avoid big quality jumps from frame to frame, we apply a "security" |
760 |
* rule that makes |last_quant - new_quant| <= 2. This rule only applies |
* rule that makes |last_quant - new_quant| <= 2. This rule only applies |
761 |
* to predicted frames (P and B) */ |
* to predicted frames (P and B) */ |
1031 |
|
|
1032 |
/* pre-process the statistics data |
/* pre-process the statistics data |
1033 |
* - for each type, count, tot_length, min_length, max_length |
* - for each type, count, tot_length, min_length, max_length |
1034 |
* - set keyframes_locations */ |
* - set keyframes_locations, tot_prescaled */ |
1035 |
static void |
static void |
1036 |
first_pass_stats_prepare_data(rc_2pass2_t * rc) |
first_pass_stats_prepare_data(rc_2pass2_t * rc) |
1037 |
{ |
{ |
1048 |
} |
} |
1049 |
|
|
1050 |
rc->max_length = INT_MIN; |
rc->max_length = INT_MIN; |
1051 |
|
rc->tot_weighted = 0; |
1052 |
|
|
1053 |
/* Loop through all frames and find/compute all the stuff this function |
/* Loop through all frames and find/compute all the stuff this function |
1054 |
* is supposed to do */ |
* is supposed to do */ |
1058 |
rc->count[s->type-1]++; |
rc->count[s->type-1]++; |
1059 |
rc->tot_length[s->type-1] += s->length; |
rc->tot_length[s->type-1] += s->length; |
1060 |
rc->tot_invariant[s->type-1] += s->invariant; |
rc->tot_invariant[s->type-1] += s->invariant; |
1061 |
|
if (s->zone_mode != XVID_ZONE_QUANT) |
1062 |
|
rc->tot_weighted += (int)(s->weight*(s->length - s->invariant)); |
1063 |
|
|
1064 |
if (s->length < rc->min_length[s->type-1]) { |
if (s->length < rc->min_length[s->type-1]) { |
1065 |
rc->min_length[s->type-1] = s->length; |
rc->min_length[s->type-1] = s->length; |
1094 |
int i,j; |
int i,j; |
1095 |
int n = 0; |
int n = 0; |
1096 |
|
|
|
rc->avg_weight = 0.0; |
|
1097 |
rc->tot_quant = 0; |
rc->tot_quant = 0; |
1098 |
rc->tot_quant_invariant = 0; |
rc->tot_quant_invariant = 0; |
1099 |
|
|
1102 |
rc->stats[j].zone_mode = XVID_ZONE_WEIGHT; |
rc->stats[j].zone_mode = XVID_ZONE_WEIGHT; |
1103 |
rc->stats[j].weight = 1.0; |
rc->stats[j].weight = 1.0; |
1104 |
} |
} |
|
rc->avg_weight += rc->num_frames * 1.0; |
|
1105 |
n += rc->num_frames; |
n += rc->num_frames; |
1106 |
} |
} |
1107 |
|
|
1110 |
|
|
1111 |
int next = (i+1<create->num_zones) ? create->zones[i+1].frame : rc->num_frames; |
int next = (i+1<create->num_zones) ? create->zones[i+1].frame : rc->num_frames; |
1112 |
|
|
1113 |
|
/* Zero weight make no sense */ |
1114 |
|
if (create->zones[i].increment == 0) create->zones[i].increment = 1; |
1115 |
|
/* And obviously an undetermined infinite makes even less sense */ |
1116 |
|
if (create->zones[i].base == 0) create->zones[i].base = 1; |
1117 |
|
|
1118 |
if (i==0 && create->zones[i].frame > 0) { |
if (i==0 && create->zones[i].frame > 0) { |
1119 |
for (j = 0; j < create->zones[i].frame && j < rc->num_frames; j++) { |
for (j = 0; j < create->zones[i].frame && j < rc->num_frames; j++) { |
1120 |
rc->stats[j].zone_mode = XVID_ZONE_WEIGHT; |
rc->stats[j].zone_mode = XVID_ZONE_WEIGHT; |
1121 |
rc->stats[j].weight = 1.0; |
rc->stats[j].weight = 1.0; |
1122 |
} |
} |
|
rc->avg_weight += create->zones[i].frame * 1.0; |
|
1123 |
n += create->zones[i].frame; |
n += create->zones[i].frame; |
1124 |
} |
} |
1125 |
|
|
1129 |
rc->stats[j].weight = (double)create->zones[i].increment / (double)create->zones[i].base; |
rc->stats[j].weight = (double)create->zones[i].increment / (double)create->zones[i].base; |
1130 |
} |
} |
1131 |
next -= create->zones[i].frame; |
next -= create->zones[i].frame; |
|
rc->avg_weight += (double)(next * create->zones[i].increment) / (double)create->zones[i].base; |
|
1132 |
n += next; |
n += next; |
1133 |
} else{ /* XVID_ZONE_QUANT */ |
} else{ /* XVID_ZONE_QUANT */ |
1134 |
for (j = create->zones[i].frame; j < next && j < rc->num_frames; j++ ) { |
for (j = create->zones[i].frame; j < next && j < rc->num_frames; j++ ) { |
1139 |
} |
} |
1140 |
} |
} |
1141 |
} |
} |
|
rc->avg_weight = n>0 ? rc->avg_weight/n : 1.0; |
|
|
|
|
|
DPRINTF(XVID_DEBUG_RC, "[xvid rc] -- center_weight:%f (for %d frames) fixed_bytes:%d\n", rc->avg_weight, n, rc->tot_quant); |
|
1142 |
} |
} |
1143 |
|
|
1144 |
|
|
1147 |
first_pass_scale_curve_internal(rc_2pass2_t *rc) |
first_pass_scale_curve_internal(rc_2pass2_t *rc) |
1148 |
{ |
{ |
1149 |
int64_t target; |
int64_t target; |
|
int64_t pass1_length; |
|
1150 |
int64_t total_invariant; |
int64_t total_invariant; |
1151 |
double scaler; |
double scaler; |
1152 |
int i, num_MBs; |
int i, num_MBs; |
1165 |
target = rc->target; |
target = rc->target; |
1166 |
target -= rc->tot_quant; |
target -= rc->tot_quant; |
1167 |
|
|
|
/* Do the same for the first pass data */ |
|
|
pass1_length = rc->tot_length[XVID_TYPE_IVOP-1]; |
|
|
pass1_length += rc->tot_length[XVID_TYPE_PVOP-1]; |
|
|
pass1_length += rc->tot_length[XVID_TYPE_BVOP-1]; |
|
|
pass1_length -= rc->tot_quant; |
|
|
|
|
1168 |
/* Let's compute a linear scaler in order to perform curve scaling */ |
/* Let's compute a linear scaler in order to perform curve scaling */ |
1169 |
scaler = (double)(target - total_invariant) / (double)(pass1_length - total_invariant); |
scaler = (double)(target - total_invariant) / (double)(rc->tot_weighted); |
1170 |
|
|
1171 |
#ifdef PASS_SMALLER |
#ifdef SMART_OVERFLOW_SETTING |
1172 |
if ((target - total_invariant) <= 0 || |
if (scaler > 0.9) { |
1173 |
(pass1_length - total_invariant) <= 0 || |
rc->param.max_overflow_degradation *= 5; |
1174 |
target >= pass1_length) { |
rc->param.max_overflow_improvement *= 5; |
1175 |
DPRINTF(XVID_DEBUG_RC, "[xvid rc] -- WARNING: Undersize detected before correction\n"); |
rc->param.overflow_control_strength *= 3; |
1176 |
scaler = 1.0; |
} else if (scaler > 0.6) { |
1177 |
|
rc->param.max_overflow_degradation *= 2; |
1178 |
|
rc->param.max_overflow_improvement *= 2; |
1179 |
|
rc->param.overflow_control_strength *= 2; |
1180 |
|
} else { |
1181 |
|
rc->min_quant = 2; |
1182 |
} |
} |
1183 |
#endif |
#endif |
1184 |
|
|
1223 |
} |
} |
1224 |
|
|
1225 |
/* Compute the scaled length -- only non invariant data length is scaled */ |
/* Compute the scaled length -- only non invariant data length is scaled */ |
1226 |
len = s->invariant + (int)((double)(s->length-s->invariant) * scaler * s->weight / rc->avg_weight); |
len = s->invariant + (int)((double)(s->length-s->invariant) * scaler * s->weight); |
1227 |
|
|
1228 |
/* Compare with the computed minimum */ |
/* Compare with the computed minimum */ |
1229 |
if (len < rc->min_length[s->type-1]) { |
if (len < rc->min_length[s->type-1]) { |
1235 |
* total counters, as we prepare a second pass for 'regular' |
* total counters, as we prepare a second pass for 'regular' |
1236 |
* frames */ |
* frames */ |
1237 |
target -= s->scaled_length; |
target -= s->scaled_length; |
|
pass1_length -= s->length; |
|
1238 |
} else { |
} else { |
1239 |
/* Do nothing for now, we'll scale this later */ |
/* Do nothing for now, we'll scale this later */ |
1240 |
s->scaled_length = 0; |
s->scaled_length = 0; |
1245 |
* total counters. Now, it's possible to scale the 'regular' frames. */ |
* total counters. Now, it's possible to scale the 'regular' frames. */ |
1246 |
|
|
1247 |
/* Scaling factor for 'regular' frames */ |
/* Scaling factor for 'regular' frames */ |
1248 |
scaler = (double)(target - total_invariant) / (double)(pass1_length - total_invariant); |
scaler = (double)(target - total_invariant) / (double)(rc->tot_weighted); |
|
|
|
|
#ifdef PASS_SMALLER |
|
|
/* Detect undersizing */ |
|
|
if (target <= 0 || pass1_length <= 0 || target >= pass1_length) { |
|
|
DPRINTF(XVID_DEBUG_RC, "[xvid rc] -- WARNING: Undersize detected after correction\n"); |
|
|
scaler = 1.0; |
|
|
} |
|
|
#endif |
|
1249 |
|
|
1250 |
/* Do another pass with the new scaler */ |
/* Do another pass with the new scaler */ |
1251 |
for (i=0; i<rc->num_frames; i++) { |
for (i=0; i<rc->num_frames; i++) { |
1253 |
|
|
1254 |
/* Ignore frame with forced frame sizes */ |
/* Ignore frame with forced frame sizes */ |
1255 |
if (s->scaled_length == 0) |
if (s->scaled_length == 0) |
1256 |
s->scaled_length = s->invariant + (int)((double)(s->length-s->invariant) * scaler * s->weight / rc->avg_weight); |
s->scaled_length = s->invariant + (int)((double)(s->length-s->invariant) * scaler * s->weight); |
1257 |
} |
} |
1258 |
|
|
1259 |
/* Job done */ |
/* Job done */ |
1420 |
return; |
return; |
1421 |
} |
} |
1422 |
|
|
1423 |
|
|
1424 |
|
#ifdef VBV |
1425 |
|
|
1426 |
|
/***************************************************************************** |
1427 |
|
* VBV compliancy check and scale |
1428 |
|
* MPEG-4 standard specifies certain restrictions for bitrate/framesize in VBR |
1429 |
|
* to enable playback on devices with limited readspeed and memory (and which |
1430 |
|
* aren't...) |
1431 |
|
* |
1432 |
|
* DivX profiles have 2 criteria: VBV as in MPEG standard |
1433 |
|
* a limit on peak bitrate for any 3 seconds |
1434 |
|
* |
1435 |
|
* But if VBV is fulfilled, peakrate is automatically fulfilled in any profile |
1436 |
|
* define so far, so we check for it (for completeness) but correct only VBV |
1437 |
|
* |
1438 |
|
*****************************************************************************/ |
1439 |
|
|
1440 |
|
#define VBV_COMPLIANT 0 |
1441 |
|
#define VBV_UNDERFLOW 1 /* video buffer runs empty */ |
1442 |
|
#define VBV_OVERFLOW 2 /* doesn't exist for VBR encoding */ |
1443 |
|
#define VBV_PEAKRATE 4 /* peak bitrate (within 3s) violated */ |
1444 |
|
|
1445 |
|
static int check_curve_for_vbv_compliancy(rc_2pass2_t * rc, const float fps) |
1446 |
|
{ |
1447 |
|
/* We do all calculations in float, for higher accuracy, and bytes for convenience |
1448 |
|
|
1449 |
|
typical values from DivX Home Theater profile: |
1450 |
|
vbvsize= 384*1024 (384kB), vbvinitial= 288*1024 (75% fill) |
1451 |
|
maxrate= 4000000 (4MBps), peakrate= 10000000 (10MBps) |
1452 |
|
|
1453 |
|
PAL: offset3s = 75 (3 seconds of 25fps) |
1454 |
|
NTSC: offset3s = 90 (3 seconds of 29.97fps) or 72 (3 seconds of 23.976fps) |
1455 |
|
*/ |
1456 |
|
|
1457 |
|
const float vbvsize = (float)rc->param.vbvsize/8.f; |
1458 |
|
float vbvfill = (float)rc->param.vbvinitial/8.f; |
1459 |
|
|
1460 |
|
const float maxrate = (float)rc->param.vbv_maxrate; |
1461 |
|
const float peakrate = (float)rc->param.vbv_peakrate; |
1462 |
|
const float r0 = (int)(maxrate/fps+0.5)/8.f; |
1463 |
|
|
1464 |
|
int bytes3s = 0; |
1465 |
|
int offset3s = (int)(3.f*fps+0.5); |
1466 |
|
|
1467 |
|
int i; |
1468 |
|
for (i=0; i<rc->num_frames; i++) { |
1469 |
|
/* DivX 3s peak bitrate check */ |
1470 |
|
|
1471 |
|
bytes3s += rc->stats[i].scaled_length; |
1472 |
|
if (i>=offset3s) |
1473 |
|
bytes3s -= rc->stats[i-offset3s].scaled_length; |
1474 |
|
|
1475 |
|
if (8.f*bytes3s > 3*peakrate) |
1476 |
|
return VBV_PEAKRATE; |
1477 |
|
|
1478 |
|
/* update vbv fill level */ |
1479 |
|
|
1480 |
|
vbvfill += r0 - rc->stats[i].scaled_length; |
1481 |
|
|
1482 |
|
/* this check is _NOT_ an "overflow"! only reading from disk stops then */ |
1483 |
|
if (vbvfill > vbvsize) |
1484 |
|
vbvfill = vbvsize; |
1485 |
|
|
1486 |
|
/* but THIS would be an underflow. report it! */ |
1487 |
|
if (vbvfill < 0) |
1488 |
|
return VBV_UNDERFLOW; |
1489 |
|
} |
1490 |
|
|
1491 |
|
return VBV_COMPLIANT; |
1492 |
|
} |
1493 |
|
/* idea: min(vbvfill) could be stored to print "minimum buffer fill" */ |
1494 |
|
|
1495 |
|
|
1496 |
|
|
1497 |
|
static int scale_curve_for_vbv_compliancy(rc_2pass2_t * rc, const float fps) |
1498 |
|
{ |
1499 |
|
/* correct any VBV violations. Peak bitrate violations disappears |
1500 |
|
by this automatically |
1501 |
|
|
1502 |
|
This implementation follows |
1503 |
|
|
1504 |
|
Westerink, Rajagopalan, Gonzales "Two-pass MPEG-2 variable-bitrate encoding" |
1505 |
|
IBM J. RES. DEVELOP. VOL 43, No. 4, July 1999, p.471--488 |
1506 |
|
|
1507 |
|
Thanks, guys! This paper rocks!!! |
1508 |
|
*/ |
1509 |
|
|
1510 |
|
/* |
1511 |
|
For each scene of len N, we have to check up to N^2 possible buffer fills. |
1512 |
|
This works well with MPEG-2 where N==12 or so, but for MPEG-4 it's a |
1513 |
|
little slow... |
1514 |
|
*/ |
1515 |
|
const float vbvsize = (float)rc->param.vbvsize/8.f; |
1516 |
|
const float vbvinitial = (float)rc->param.vbvinitial/8.f; |
1517 |
|
|
1518 |
|
const float maxrate = 0.9*rc->param.vbv_maxrate; |
1519 |
|
const float vbvlow = 0.10f*vbvsize; |
1520 |
|
const float r0 = (int)(maxrate/fps+0.5)/8.f; |
1521 |
|
|
1522 |
|
int i,k,l,n,violation = 0; |
1523 |
|
float *scenefactor; |
1524 |
|
int *scenestart; |
1525 |
|
int *scenelength; |
1526 |
|
|
1527 |
|
/* first step: determine how many "scenes" there are and store their boundaries |
1528 |
|
we could get all this from existing keyframe_positions, somehow, but there we |
1529 |
|
don't have a min_scenelength, and it's no big deal to get it again. */ |
1530 |
|
|
1531 |
|
const int min_scenelength = 50; |
1532 |
|
int num_scenes = 0; |
1533 |
|
int last_scene = -999; |
1534 |
|
for (i=0; i<rc->num_frames; i++) { |
1535 |
|
if ( (rc->stats[i].type == XVID_TYPE_IVOP) && (i-last_scene>min_scenelength) ) |
1536 |
|
{ |
1537 |
|
last_scene = i; |
1538 |
|
num_scenes++; |
1539 |
|
} |
1540 |
|
} |
1541 |
|
|
1542 |
|
scenefactor = (float*)malloc( num_scenes*sizeof(float) ); |
1543 |
|
scenestart = (int*)malloc( num_scenes*sizeof(int) ); |
1544 |
|
scenelength = (int*)malloc( num_scenes*sizeof(int) ); |
1545 |
|
|
1546 |
|
if ((!scenefactor) || (!scenestart) || (!scenelength) ) |
1547 |
|
{ |
1548 |
|
free(scenefactor); |
1549 |
|
free(scenestart); |
1550 |
|
free(scenelength); |
1551 |
|
/* remember: free(0) is valid and does exactly nothing. */ |
1552 |
|
return -1; |
1553 |
|
} |
1554 |
|
|
1555 |
|
/* count again and safe the length/position */ |
1556 |
|
|
1557 |
|
num_scenes = 0; |
1558 |
|
last_scene = -999; |
1559 |
|
for (i=0; i<rc->num_frames; i++) { |
1560 |
|
if ( (rc->stats[i].type == XVID_TYPE_IVOP) && (i-last_scene>min_scenelength) ) |
1561 |
|
{ |
1562 |
|
if (num_scenes>0) |
1563 |
|
scenelength[num_scenes-1]=i-last_scene; |
1564 |
|
scenestart[num_scenes]=i; |
1565 |
|
num_scenes++; |
1566 |
|
last_scene = i; |
1567 |
|
} |
1568 |
|
} |
1569 |
|
scenelength[num_scenes-1]=i-last_scene; |
1570 |
|
|
1571 |
|
/* second step: check for each scene, how much we can scale its frames up or down |
1572 |
|
such that the VBV restriction is just fulfilled |
1573 |
|
*/ |
1574 |
|
|
1575 |
|
|
1576 |
|
#define R(k,n) (((n)+1-(k))*r0) /* how much enters the buffer between frame k and n */ |
1577 |
|
for (l=0; l<num_scenes;l++) |
1578 |
|
{ |
1579 |
|
const int start = scenestart[l]; |
1580 |
|
const int length = scenelength[l]; |
1581 |
|
twopass_stat_t * frames = &rc->stats[start]; |
1582 |
|
|
1583 |
|
float S0n,Skn; |
1584 |
|
float f,minf = 99999.f; |
1585 |
|
|
1586 |
|
S0n=0.; |
1587 |
|
for (n=0;n<=length-1;n++) |
1588 |
|
{ |
1589 |
|
S0n += frames[n].scaled_length; |
1590 |
|
|
1591 |
|
k=0; |
1592 |
|
Skn = S0n; |
1593 |
|
f = (R(k,n-1) + (vbvinitial - vbvlow)) / Skn; |
1594 |
|
if (f < minf) |
1595 |
|
minf = f; |
1596 |
|
|
1597 |
|
for (k=1;k<=n;k++) |
1598 |
|
{ |
1599 |
|
Skn -= frames[k].scaled_length; |
1600 |
|
|
1601 |
|
f = (R(k,n-1) + (vbvsize - vbvlow)) / Skn; |
1602 |
|
if (f < minf) |
1603 |
|
minf = f; |
1604 |
|
} |
1605 |
|
} |
1606 |
|
|
1607 |
|
/* special case: at the end, fill buffer up to vbvinitial again |
1608 |
|
TODO: Allow other values for buffer fill between scenes |
1609 |
|
e.g. if n=N is smallest f-value, then check for better value */ |
1610 |
|
|
1611 |
|
n=length; |
1612 |
|
k=0; |
1613 |
|
Skn = S0n; |
1614 |
|
f = R(k,n-1)/Skn; |
1615 |
|
if (f < minf) |
1616 |
|
minf = f; |
1617 |
|
|
1618 |
|
for (k=1;k<=n-1;k++) |
1619 |
|
{ |
1620 |
|
Skn -= frames[k].scaled_length; |
1621 |
|
|
1622 |
|
f = (R(k,n-1) + (vbvinitial - vbvlow)) / Skn; |
1623 |
|
if (f < minf) |
1624 |
|
minf = f; |
1625 |
|
} |
1626 |
|
|
1627 |
|
#ifdef VBV_DEBUG |
1628 |
|
printf("Scene %d (Frames %d-%d): VBVfactor %f\n", l, start, start+length-1 , minf); |
1629 |
|
#endif |
1630 |
|
|
1631 |
|
scenefactor[l] = minf; |
1632 |
|
} |
1633 |
|
#undef R |
1634 |
|
|
1635 |
|
/* last step: now we know of any scene how much it can be scaled up or down without |
1636 |
|
violating VBV. Next, distribute bits from the evil scenes to the good ones */ |
1637 |
|
|
1638 |
|
do |
1639 |
|
{ |
1640 |
|
float S_red = 0.f; /* how much to redistribute */ |
1641 |
|
float S_elig = 0.f; /* sum of bit for those scenes you can still swallow something*/ |
1642 |
|
int l; |
1643 |
|
|
1644 |
|
for (l=0;l<num_scenes;l++) /* check how much is wrong */ |
1645 |
|
{ |
1646 |
|
const int start = scenestart[l]; |
1647 |
|
const int length = scenelength[l]; |
1648 |
|
twopass_stat_t * frames = &rc->stats[start]; |
1649 |
|
|
1650 |
|
if (scenefactor[l] == 1.) /* exactly 1 means "don't touch this anymore!" */ |
1651 |
|
continue; |
1652 |
|
|
1653 |
|
if (scenefactor[l] > 1.) /* within limits */ |
1654 |
|
{ |
1655 |
|
for (n= 0; n < length; n++) |
1656 |
|
S_elig += frames[n].scaled_length; |
1657 |
|
} |
1658 |
|
else /* underflowing segment */ |
1659 |
|
{ |
1660 |
|
for (n= 0; n < length; n++) |
1661 |
|
{ |
1662 |
|
float newbytes = (float)frames[n].scaled_length * scenefactor[l]; |
1663 |
|
S_red += (float)frames[n].scaled_length - (float)newbytes; |
1664 |
|
frames[n].scaled_length =(int)newbytes; |
1665 |
|
} |
1666 |
|
scenefactor[l] = 1.f; |
1667 |
|
} |
1668 |
|
} |
1669 |
|
|
1670 |
|
if (S_red < 1.f) /* no more underflows */ |
1671 |
|
break; |
1672 |
|
|
1673 |
|
if (S_elig < 1.f) |
1674 |
|
{ |
1675 |
|
#ifdef VBV_DEBUG |
1676 |
|
fprintf(stderr,"Everything underflowing. \n"); |
1677 |
|
#endif |
1678 |
|
free(scenefactor); |
1679 |
|
free(scenestart); |
1680 |
|
free(scenelength); |
1681 |
|
return -2; |
1682 |
|
} |
1683 |
|
|
1684 |
|
const float f_red = (1.f + S_red/S_elig); |
1685 |
|
|
1686 |
|
#ifdef VBV_DEBUG |
1687 |
|
printf("Moving %.0f kB to avoid buffer underflow, correction factor: %.5f\n",S_red/1024.f,f_red); |
1688 |
|
#endif |
1689 |
|
|
1690 |
|
violation=0; |
1691 |
|
for (l=0; l<num_scenes; l++) /* scale remaining scenes up to meet total size */ |
1692 |
|
{ |
1693 |
|
const int start = scenestart[l]; |
1694 |
|
const int length = scenelength[l]; |
1695 |
|
twopass_stat_t * frames = &rc->stats[start]; |
1696 |
|
|
1697 |
|
if (scenefactor[l] == 1.) |
1698 |
|
continue; |
1699 |
|
|
1700 |
|
/* there shouldn't be any segments with factor<1 left, so all the rest is >1 */ |
1701 |
|
|
1702 |
|
for (n= 0; n < length; n++) |
1703 |
|
{ |
1704 |
|
frames[n].scaled_length = (int)(frames[n].scaled_length * f_red + 0.5); |
1705 |
|
} |
1706 |
|
|
1707 |
|
scenefactor[l] /= f_red; |
1708 |
|
if (scenefactor[l] < 1.f) |
1709 |
|
violation=1; |
1710 |
|
} |
1711 |
|
|
1712 |
|
} while (violation); |
1713 |
|
|
1714 |
|
free(scenefactor); |
1715 |
|
free(scenestart); |
1716 |
|
free(scenelength); |
1717 |
|
return 0; |
1718 |
|
} |
1719 |
|
|
1720 |
|
|
1721 |
|
#endif |
1722 |
|
|
1723 |
|
|
1724 |
/***************************************************************************** |
/***************************************************************************** |
1725 |
* Still more low level stuff (nothing to do with stats treatment) |
* Still more low level stuff (nothing to do with stats treatment) |
1726 |
****************************************************************************/ |
****************************************************************************/ |