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-rw-r--r--vorbis/lib/bitrate.c252
1 files changed, 0 insertions, 252 deletions
diff --git a/vorbis/lib/bitrate.c b/vorbis/lib/bitrate.c
deleted file mode 100644
index 9605514..0000000
--- a/vorbis/lib/bitrate.c
+++ /dev/null
@@ -1,252 +0,0 @@
-/********************************************************************
- * *
- * THIS FILE IS PART OF THE OggVorbis SOFTWARE CODEC SOURCE CODE. *
- * USE, DISTRIBUTION AND REPRODUCTION OF THIS LIBRARY SOURCE IS *
- * GOVERNED BY A BSD-STYLE SOURCE LICENSE INCLUDED WITH THIS SOURCE *
- * IN 'COPYING'. PLEASE READ THESE TERMS BEFORE DISTRIBUTING. *
- * *
- * THE OggVorbis SOURCE CODE IS (C) COPYRIGHT 1994-2009 *
- * by the Xiph.Org Foundation http://www.xiph.org/ *
- * *
- ********************************************************************
-
- function: bitrate tracking and management
-
- ********************************************************************/
-
-#include <stdlib.h>
-#include <string.h>
-#include <math.h>
-#include <ogg/ogg.h>
-#include "vorbis/codec.h"
-#include "codec_internal.h"
-#include "os.h"
-#include "misc.h"
-#include "bitrate.h"
-
-/* compute bitrate tracking setup */
-void vorbis_bitrate_init(vorbis_info *vi,bitrate_manager_state *bm){
- codec_setup_info *ci=vi->codec_setup;
- bitrate_manager_info *bi=&ci->bi;
-
- memset(bm,0,sizeof(*bm));
-
- if(bi && (bi->reservoir_bits>0)){
- long ratesamples=vi->rate;
- int halfsamples=ci->blocksizes[0]>>1;
-
- bm->short_per_long=ci->blocksizes[1]/ci->blocksizes[0];
- bm->managed=1;
-
- bm->avg_bitsper= rint(1.*bi->avg_rate*halfsamples/ratesamples);
- bm->min_bitsper= rint(1.*bi->min_rate*halfsamples/ratesamples);
- bm->max_bitsper= rint(1.*bi->max_rate*halfsamples/ratesamples);
-
- bm->avgfloat=PACKETBLOBS/2;
-
- /* not a necessary fix, but one that leads to a more balanced
- typical initialization */
- {
- long desired_fill=bi->reservoir_bits*bi->reservoir_bias;
- bm->minmax_reservoir=desired_fill;
- bm->avg_reservoir=desired_fill;
- }
-
- }
-}
-
-void vorbis_bitrate_clear(bitrate_manager_state *bm){
- memset(bm,0,sizeof(*bm));
- return;
-}
-
-int vorbis_bitrate_managed(vorbis_block *vb){
- vorbis_dsp_state *vd=vb->vd;
- private_state *b=vd->backend_state;
- bitrate_manager_state *bm=&b->bms;
-
- if(bm && bm->managed)return(1);
- return(0);
-}
-
-/* finish taking in the block we just processed */
-int vorbis_bitrate_addblock(vorbis_block *vb){
- vorbis_block_internal *vbi=vb->internal;
- vorbis_dsp_state *vd=vb->vd;
- private_state *b=vd->backend_state;
- bitrate_manager_state *bm=&b->bms;
- vorbis_info *vi=vd->vi;
- codec_setup_info *ci=vi->codec_setup;
- bitrate_manager_info *bi=&ci->bi;
-
- int choice=rint(bm->avgfloat);
- long this_bits=oggpack_bytes(vbi->packetblob[choice])*8;
- long min_target_bits=(vb->W?bm->min_bitsper*bm->short_per_long:bm->min_bitsper);
- long max_target_bits=(vb->W?bm->max_bitsper*bm->short_per_long:bm->max_bitsper);
- int samples=ci->blocksizes[vb->W]>>1;
- long desired_fill=bi->reservoir_bits*bi->reservoir_bias;
- if(!bm->managed){
- /* not a bitrate managed stream, but for API simplicity, we'll
- buffer the packet to keep the code path clean */
-
- if(bm->vb)return(-1); /* one has been submitted without
- being claimed */
- bm->vb=vb;
- return(0);
- }
-
- bm->vb=vb;
-
- /* look ahead for avg floater */
- if(bm->avg_bitsper>0){
- double slew=0.;
- long avg_target_bits=(vb->W?bm->avg_bitsper*bm->short_per_long:bm->avg_bitsper);
- double slewlimit= 15./bi->slew_damp;
-
- /* choosing a new floater:
- if we're over target, we slew down
- if we're under target, we slew up
-
- choose slew as follows: look through packetblobs of this frame
- and set slew as the first in the appropriate direction that
- gives us the slew we want. This may mean no slew if delta is
- already favorable.
-
- Then limit slew to slew max */
-
- if(bm->avg_reservoir+(this_bits-avg_target_bits)>desired_fill){
- while(choice>0 && this_bits>avg_target_bits &&
- bm->avg_reservoir+(this_bits-avg_target_bits)>desired_fill){
- choice--;
- this_bits=oggpack_bytes(vbi->packetblob[choice])*8;
- }
- }else if(bm->avg_reservoir+(this_bits-avg_target_bits)<desired_fill){
- while(choice+1<PACKETBLOBS && this_bits<avg_target_bits &&
- bm->avg_reservoir+(this_bits-avg_target_bits)<desired_fill){
- choice++;
- this_bits=oggpack_bytes(vbi->packetblob[choice])*8;
- }
- }
-
- slew=rint(choice-bm->avgfloat)/samples*vi->rate;
- if(slew<-slewlimit)slew=-slewlimit;
- if(slew>slewlimit)slew=slewlimit;
- choice=rint(bm->avgfloat+= slew/vi->rate*samples);
- this_bits=oggpack_bytes(vbi->packetblob[choice])*8;
- }
-
-
-
- /* enforce min(if used) on the current floater (if used) */
- if(bm->min_bitsper>0){
- /* do we need to force the bitrate up? */
- if(this_bits<min_target_bits){
- while(bm->minmax_reservoir-(min_target_bits-this_bits)<0){
- choice++;
- if(choice>=PACKETBLOBS)break;
- this_bits=oggpack_bytes(vbi->packetblob[choice])*8;
- }
- }
- }
-
- /* enforce max (if used) on the current floater (if used) */
- if(bm->max_bitsper>0){
- /* do we need to force the bitrate down? */
- if(this_bits>max_target_bits){
- while(bm->minmax_reservoir+(this_bits-max_target_bits)>bi->reservoir_bits){
- choice--;
- if(choice<0)break;
- this_bits=oggpack_bytes(vbi->packetblob[choice])*8;
- }
- }
- }
-
- /* Choice of packetblobs now made based on floater, and min/max
- requirements. Now boundary check extreme choices */
-
- if(choice<0){
- /* choosing a smaller packetblob is insufficient to trim bitrate.
- frame will need to be truncated */
- long maxsize=(max_target_bits+(bi->reservoir_bits-bm->minmax_reservoir))/8;
- bm->choice=choice=0;
-
- if(oggpack_bytes(vbi->packetblob[choice])>maxsize){
-
- oggpack_writetrunc(vbi->packetblob[choice],maxsize*8);
- this_bits=oggpack_bytes(vbi->packetblob[choice])*8;
- }
- }else{
- long minsize=(min_target_bits-bm->minmax_reservoir+7)/8;
- if(choice>=PACKETBLOBS)
- choice=PACKETBLOBS-1;
-
- bm->choice=choice;
-
- /* prop up bitrate according to demand. pad this frame out with zeroes */
- minsize-=oggpack_bytes(vbi->packetblob[choice]);
- while(minsize-->0)oggpack_write(vbi->packetblob[choice],0,8);
- this_bits=oggpack_bytes(vbi->packetblob[choice])*8;
-
- }
-
- /* now we have the final packet and the final packet size. Update statistics */
- /* min and max reservoir */
- if(bm->min_bitsper>0 || bm->max_bitsper>0){
-
- if(max_target_bits>0 && this_bits>max_target_bits){
- bm->minmax_reservoir+=(this_bits-max_target_bits);
- }else if(min_target_bits>0 && this_bits<min_target_bits){
- bm->minmax_reservoir+=(this_bits-min_target_bits);
- }else{
- /* inbetween; we want to take reservoir toward but not past desired_fill */
- if(bm->minmax_reservoir>desired_fill){
- if(max_target_bits>0){ /* logical bulletproofing against initialization state */
- bm->minmax_reservoir+=(this_bits-max_target_bits);
- if(bm->minmax_reservoir<desired_fill)bm->minmax_reservoir=desired_fill;
- }else{
- bm->minmax_reservoir=desired_fill;
- }
- }else{
- if(min_target_bits>0){ /* logical bulletproofing against initialization state */
- bm->minmax_reservoir+=(this_bits-min_target_bits);
- if(bm->minmax_reservoir>desired_fill)bm->minmax_reservoir=desired_fill;
- }else{
- bm->minmax_reservoir=desired_fill;
- }
- }
- }
- }
-
- /* avg reservoir */
- if(bm->avg_bitsper>0){
- long avg_target_bits=(vb->W?bm->avg_bitsper*bm->short_per_long:bm->avg_bitsper);
- bm->avg_reservoir+=this_bits-avg_target_bits;
- }
-
- return(0);
-}
-
-int vorbis_bitrate_flushpacket(vorbis_dsp_state *vd,ogg_packet *op){
- private_state *b=vd->backend_state;
- bitrate_manager_state *bm=&b->bms;
- vorbis_block *vb=bm->vb;
- int choice=PACKETBLOBS/2;
- if(!vb)return 0;
-
- if(op){
- vorbis_block_internal *vbi=vb->internal;
-
- if(vorbis_bitrate_managed(vb))
- choice=bm->choice;
-
- op->packet=oggpack_get_buffer(vbi->packetblob[choice]);
- op->bytes=oggpack_bytes(vbi->packetblob[choice]);
- op->b_o_s=0;
- op->e_o_s=vb->eofflag;
- op->granulepos=vb->granulepos;
- op->packetno=vb->sequence; /* for sake of completeness */
- }
-
- bm->vb=0;
- return(1);
-}
generated by cgit v1.1 at 2024-11-04 21:32:27 +0000