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mpv/libmpdemux/demux_asf.c
diego 21c200e767 FFmpeg now uses different (unified) #include paths. 
git-svn-id: svn://svn.mplayerhq.hu/mplayer/trunk@26101 b3059339-0415-0410-9bf9-f77b7e298cf2
2008-02-25 15:46:36 +00:00

684 lines
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C
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// ASF file parser for DEMUXER v0.3 by A'rpi/ESP-team
#include <stdio.h>
#include <stdlib.h>
#include <unistd.h>
#include "config.h"
#include "mp_msg.h"
#include "help_mp.h"
#include "stream/stream.h"
#include "asf.h"
#include "demuxer.h"
#include "libvo/fastmemcpy.h"
#include "libavutil/intreadwrite.h"
// defined at asfheader.c:
extern int asf_check_header(demuxer_t *demuxer);
extern int read_asf_header(demuxer_t *demuxer,struct asf_priv* asf);
// based on asf file-format doc by Eugene [http://divx.euro.ru]
/**
* \brief reads int stored in number of bytes given by len
* \param ptr pointer to read from, is incremented appropriately
* \param len lowest 2 bits indicate number of bytes to read
* \param def default value to return if len is invalid
*/
static inline unsigned read_varlen(uint8_t **ptr, int len, int def) {
const uint8_t *p = *ptr;
len &= 3;
switch (len) {
case 1: *ptr += 1; return *p;
case 2: *ptr += 2; return AV_RL16(p);
case 3: *ptr += 4; return AV_RL32(p);
}
return def;
}
/**
* \brief checks if there is enough data to read the bytes given by len
* \param ptr pointer to read from
* \param endptr pointer to the end of the buffer
* \param len lowest 2 bits indicate number of bytes to read
*/
static inline int check_varlen(uint8_t *ptr, uint8_t *endptr, int len) {
return len&3 ? ptr + (1<<(len&3 - 1)) - 1 < endptr : 1;
}
static void asf_descrambling(unsigned char **src,unsigned len, struct asf_priv* asf){
unsigned char *dst=malloc(len);
unsigned char *s2=*src;
unsigned i=0,x,y;
while(len>=asf->scrambling_h*asf->scrambling_w*asf->scrambling_b+i){
// mp_msg(MSGT_DEMUX,MSGL_DBG4,"descrambling! (w=%d b=%d)\n",w,asf_scrambling_b);
//i+=asf_scrambling_h*asf_scrambling_w;
for(x=0;x<asf->scrambling_w;x++)
for(y=0;y<asf->scrambling_h;y++){
fast_memcpy(dst+i,s2+(y*asf->scrambling_w+x)*asf->scrambling_b,asf->scrambling_b);
i+=asf->scrambling_b;
}
s2+=asf->scrambling_h*asf->scrambling_w*asf->scrambling_b;
}
//if(i<len) fast_memcpy(dst+i,src+i,len-i);
free(*src);
*src = dst;
}
/*****************************************************************
* \brief initializes asf private data
*
*/
static void init_priv (struct asf_priv* asf){
asf->last_vid_seq=-1;
asf->vid_ext_timing_index=-1;
asf->aud_ext_timing_index=-1;
asf->vid_ext_frame_index=-1;
}
#ifdef USE_LIBAVCODEC
#include "libavcodec/avcodec.h"
#else
#define FF_INPUT_BUFFER_PADDING_SIZE 8
#endif
static void demux_asf_append_to_packet(demux_packet_t* dp,unsigned char *data,int len,int offs)
{
if(dp->len!=offs && offs!=-1) mp_msg(MSGT_DEMUX,MSGL_V,"warning! fragment.len=%d BUT next fragment offset=%d \n",dp->len,offs);
dp->buffer=realloc(dp->buffer,dp->len+len+FF_INPUT_BUFFER_PADDING_SIZE);
fast_memcpy(dp->buffer+dp->len,data,len);
memset(dp->buffer+dp->len+len, 0, FF_INPUT_BUFFER_PADDING_SIZE);
mp_dbg(MSGT_DEMUX,MSGL_DBG4,"data appended! %d+%d\n",dp->len,len);
dp->len+=len;
}
static int demux_asf_read_packet(demuxer_t *demux,unsigned char *data,int len,int id,int seq,uint64_t time,unsigned short dur,int offs,int keyframe){
struct asf_priv* asf = demux->priv;
demux_stream_t *ds=NULL;
int close_seg=0;
mp_dbg(MSGT_DEMUX,MSGL_DBG4,"demux_asf.read_packet: id=%d seq=%d len=%d\n",id,seq,len);
if(demux->video->id==-1)
if(demux->v_streams[id])
demux->video->id=id;
if(demux->audio->id==-1)
if(demux->a_streams[id])
demux->audio->id=id;
if(id==demux->audio->id){
// audio
ds=demux->audio;
if(!ds->sh){
ds->sh=demux->a_streams[id];
mp_msg(MSGT_DEMUX,MSGL_V,"Auto-selected ASF audio ID = %d\n",ds->id);
}
} else
if(id==demux->video->id){
// video
ds=demux->video;
if(!ds->sh){
ds->sh=demux->v_streams[id];
mp_msg(MSGT_DEMUX,MSGL_V,"Auto-selected ASF video ID = %d\n",ds->id);
}
}
if(ds){
if(ds->asf_packet){
demux_packet_t* dp=ds->asf_packet;
if (ds==demux->video && asf->asf_is_dvr_ms) {
if (asf->new_vid_frame_seg) {
dp->pos=demux->filepos;
close_seg = 1;
} else seq = ds->asf_seq;
} else close_seg = ds->asf_seq!=seq;
if(close_seg){
// closed segment, finalize packet:
if(ds==demux->audio)
if(asf->scrambling_h>1 && asf->scrambling_w>1 && asf->scrambling_b>0)
asf_descrambling(&ds->asf_packet->buffer,ds->asf_packet->len,asf);
ds_add_packet(ds,ds->asf_packet);
ds->asf_packet=NULL;
} else {
// append data to it!
demux_asf_append_to_packet(dp,data,len,offs);
// we are ready now.
return 1;
}
}
// create new packet:
{ demux_packet_t* dp;
if(offs>0){
mp_msg(MSGT_DEMUX,MSGL_V,"warning! broken fragment, %d bytes missing \n",offs);
return 0;
}
dp=new_demux_packet(len);
fast_memcpy(dp->buffer,data,len);
if (asf->asf_is_dvr_ms)
dp->pts=time*0.0000001;
else
dp->pts=time*0.001;
dp->flags=keyframe;
// if(ds==demux->video) printf("ASF time: %8d dur: %5d \n",time,dur);
dp->pos=demux->filepos;
ds->asf_packet=dp;
ds->asf_seq=seq;
// we are ready now.
return 1;
}
}
return 0;
}
/*****************************************************************
* \brief read the replicated data associated with each segment
* \parameter pp reference to replicated data
* \parameter id stream number
* \parameter seq media object number
* \parameter keyframe key frame indicator - set to zero if keyframe, non-zero otherwise
* \parameter seg_time set to payload time when valid, if audio or new video frame payload, zero otherwise
*
*/
static void get_payload_extension_data(demuxer_t *demux, unsigned char** pp, unsigned char id, unsigned int seq, int *keyframe, uint64_t *seg_time){
struct asf_priv* asf = demux->priv;
uint64_t payload_time; //100ns units
int i, ext_max, ext_timing_index;
uint8_t *pi = *pp+4;
if(demux->video->id==-1)
if(demux->v_streams[id])
demux->video->id=id;
if(demux->audio->id==-1)
if(demux->a_streams[id])
demux->audio->id=id;
if (id!=demux->video->id && id!=demux->audio->id) return;
if (id==demux->video->id) {
ext_max = asf->vid_repdata_count;
ext_timing_index = asf->vid_ext_timing_index;
} else {
ext_max = asf->aud_repdata_count;
ext_timing_index = asf->aud_ext_timing_index;
}
*seg_time=0.0;
asf->new_vid_frame_seg = 0;
for (i=0; i<ext_max; i++) {
uint16_t payextsize;
uint8_t segment_marker;
if (id==demux->video->id)
payextsize = asf->vid_repdata_sizes[i];
else
payextsize = asf->aud_repdata_sizes[i];
if (payextsize == 65535) {
payextsize = AV_RL16(pi);
pi+=2;
}
// if this is the timing info extension then read the payload time
if (i == ext_timing_index)
payload_time = AV_RL64(pi+8);
// if this is the video frame info extension then
// set the keyframe indicator, the 'new frame segment' indicator
// and (initially) the 'frame time'
if (i == asf->vid_ext_frame_index && id==demux->video->id) {
segment_marker = pi[0];
// Known video stream segment_marker values that
// contain useful information:
//
// NTSC/ATSC (29.97fps): 0X4A 01001010
// 0X4B 01001011
// 0X49 01001001
//
// PAL/ATSC (25fps): 0X3A 00111010
// 0X3B 00111011
// 0X39 00111001
//
// ATSC progressive (29.97fps): 0X7A 01111010
// 0X7B 01111011
// 0X79 01111001
// 11111111
// ^ this is new video frame marker
//
// ^^^^ these bits indicate the framerate
// 0X4 is 29.97i, 0X3 is 25i, 0X7 is 29.97p, ???=25p
//
// ^^^ these bits indicate the frame type:
// 001 means I-frame
// 010 and 011 probably mean P and B
asf->new_vid_frame_seg = (0X08 & segment_marker) && seq != asf->last_vid_seq;
if (asf->new_vid_frame_seg) asf->last_vid_seq = seq;
if (asf->avg_vid_frame_time == 0) {
// set the average frame time initially (in 100ns units).
// This is based on what works for known samples.
// It can be extended if more samples of different types can be obtained.
if (((segment_marker & 0XF0) >> 4) == 4) {
asf->avg_vid_frame_time = (uint64_t)((1.001 / 30.0) * 10000000.0);
asf->know_frame_time=1;
} else if (((segment_marker & 0XF0) >> 4) == 3) {
asf->avg_vid_frame_time = (uint64_t)(0.04 * 10000000.0);
asf->know_frame_time=1;
} else if (((segment_marker & 0XF0) >> 4) == 6) {
asf->avg_vid_frame_time = (uint64_t)(0.02 * 10000000.0);
asf->know_frame_time=1;
} else if (((segment_marker & 0XF0) >> 4) == 7) {
asf->avg_vid_frame_time = (uint64_t)((1.001 / 60.0) * 10000000.0);
asf->know_frame_time=1;
} else {
// we dont know the frame time initially so
// make a guess and then recalculate as we go.
asf->avg_vid_frame_time = (uint64_t)((1.001 / 60.0) * 10000000.0);
asf->know_frame_time=0;
}
}
*keyframe = (asf->new_vid_frame_seg && (segment_marker & 0X07) == 1);
}
pi +=payextsize;
}
if (id==demux->video->id && asf->new_vid_frame_seg) {
asf->vid_frame_ct++;
// Some samples only have timings on key frames and
// the rest contain non-cronological timestamps. Interpolating
// the values between key frames works for all samples.
if (*keyframe) {
asf->found_first_key_frame=1;
if (!asf->know_frame_time && asf->last_key_payload_time > 0) {
// We dont know average frametime so recalculate.
// Giving precedence to the 'weight' of the existing
// average limits damage done to new value when there is
// a sudden time jump which happens occasionally.
asf->avg_vid_frame_time =
(0.9 * asf->avg_vid_frame_time) +
(0.1 * ((payload_time - asf->last_key_payload_time) / asf->vid_frame_ct));
}
asf->last_key_payload_time = payload_time;
asf->vid_frame_ct = 1;
*seg_time = payload_time;
} else
*seg_time = (asf->last_key_payload_time + (asf->avg_vid_frame_time * (asf->vid_frame_ct-1)));
}
if (id==demux->audio->id) {
if (payload_time != -1)
asf->last_aud_diff = payload_time - asf->last_aud_pts;
asf->last_aud_pts += asf->last_aud_diff;
*seg_time = asf->last_aud_pts;
}
}
//static int num_elementary_packets100=0;
//static int num_elementary_packets101=0;
// return value:
// 0 = EOF or no stream found
// 1 = successfully read a packet
static int demux_asf_fill_buffer(demuxer_t *demux, demux_stream_t *ds){
struct asf_priv* asf = demux->priv;
demux->filepos=stream_tell(demux->stream);
// Brodcast stream have movi_start==movi_end
// Better test ?
if((demux->movi_start < demux->movi_end) && (demux->filepos>=demux->movi_end)){
demux->stream->eof=1;
return 0;
}
stream_read(demux->stream,asf->packet,asf->packetsize);
if(demux->stream->eof) return 0; // EOF
if(asf->packetsize < 2) return 0; // Packet too short
{
unsigned char* p=asf->packet;
unsigned char* p_end=asf->packet+asf->packetsize;
unsigned char flags=p[0];
unsigned char segtype=p[1];
unsigned padding;
unsigned plen;
unsigned sequence;
unsigned long time=0;
unsigned short duration=0;
int segs=1;
unsigned char segsizetype=0x80;
int seg=-1;
if( mp_msg_test(MSGT_DEMUX,MSGL_DBG2) ){
int i;
for(i=0;i<FFMIN(16, asf->packetsize);i++) printf(" %02X",asf->packet[i]);
printf("\n");
}
// skip ECC data if present by testing bit 7 of flags
// 1xxxbbbb -> ecc data present, skip bbbb byte(s)
// 0xxxxxxx -> payload parsing info starts
if (flags & 0x80)
{
p += (flags & 0x0f)+1;
if (p+1 >= p_end) return 0; // Packet too short
flags = p[0];
segtype = p[1];
}
//if(segtype!=0x5d) printf("Warning! packet[4] != 0x5d \n");
p+=2; // skip flags & segtype
// Read packet size (plen):
if(!check_varlen(p, p_end, flags>> 5)) return 0; // Not enough data
plen = read_varlen(&p, flags >> 5, 0);
// Read sequence:
if(!check_varlen(p, p_end, flags>> 1)) return 0; // Not enough data
sequence = read_varlen(&p, flags >> 1, 0);
// Read padding size (padding):
if(!check_varlen(p, p_end, flags>> 3)) return 0; // Not enough data
padding = read_varlen(&p, flags >> 3, 0);
if(((flags>>5)&3)!=0){
// Explicit (absoulte) packet size
mp_dbg(MSGT_DEMUX,MSGL_DBG2,"Explicit packet size specified: %d \n",plen);
if(plen>asf->packetsize) mp_msg(MSGT_DEMUX,MSGL_V,"Warning! plen>packetsize! (%d>%d) \n",plen,asf->packetsize);
} else {
// Padding (relative) size
plen=asf->packetsize-padding;
}
// Read time & duration:
if (p+5 >= p_end) return 0; // Packet too short
time = AV_RL32(p); p+=4;
duration = AV_RL16(p); p+=2;
// Read payload flags:
if(flags&1){
// multiple sub-packets
if (p >= p_end) return 0; // Packet too short
segsizetype=p[0]>>6;
segs=p[0] & 0x3F;
++p;
}
mp_dbg(MSGT_DEMUX,MSGL_DBG4,"%08"PRIu64": flag=%02X segs=%d seq=%u plen=%u pad=%u time=%ld dur=%d\n",
(uint64_t)demux->filepos,flags,segs,sequence,plen,padding,time,duration);
for(seg=0;seg<segs;seg++){
//ASF_segmhdr_t* sh;
unsigned char streamno;
unsigned int seq;
unsigned int x; // offset or timestamp
unsigned int rlen;
//
int len;
uint64_t time2=0;
int keyframe=0;
if(p>=p_end) {
mp_msg(MSGT_DEMUX,MSGL_V,"Warning! invalid packet 1, aborting parsing...\n");
break;
}
if( mp_msg_test(MSGT_DEMUX,MSGL_DBG2) ){
int i;
printf("seg %d:",seg);
for(i=0;i<FFMIN(16, p_end - p);i++) printf(" %02X",p[i]);
printf("\n");
}
streamno=p[0]&0x7F;
if(p[0]&0x80) keyframe=1;
p++;
// Read media object number (seq):
if(!check_varlen(p, p_end, segtype >> 4)) break; // Not enough data
seq = read_varlen(&p, segtype >> 4, 0);
// Read offset or timestamp:
if(!check_varlen(p, p_end, segtype >> 2)) break; // Not enough data
x = read_varlen(&p, segtype >> 2, 0);
// Read replic.data len:
if(!check_varlen(p, p_end, segtype)) break; // Not enough data
rlen = read_varlen(&p, segtype, 0);
// printf("### rlen=%d \n",rlen);
switch(rlen){
case 0x01: // 1 = special, means grouping
//printf("grouping: %02X \n",p[0]);
++p; // skip PTS delta
break;
default:
if(rlen>=8){
p+=4; // skip object size
if (p+3 >= p_end) break; // Packet too short
time2=AV_RL32(p); // read PTS
if (asf->asf_is_dvr_ms)
get_payload_extension_data(demux, &p, streamno, seq, &keyframe, &time2);
p+=rlen-4;
} else {
mp_msg(MSGT_DEMUX,MSGL_V,"unknown segment type (rlen): 0x%02X \n",rlen);
time2=0; // unknown
p+=rlen;
}
}
if(flags&1){
// multiple segments
if(!check_varlen(p, p_end, segsizetype)) break; // Not enough data
len = read_varlen(&p, segsizetype, plen-(p-asf->packet));
} else {
// single segment
len=plen-(p-asf->packet);
}
if(len<0 || (p+len)>p_end){
mp_msg(MSGT_DEMUX,MSGL_V,"ASF_parser: warning! segment len=%d\n",len);
}
mp_dbg(MSGT_DEMUX,MSGL_DBG4," seg #%d: streamno=%d seq=%d type=%02X len=%d\n",seg,streamno,seq,rlen,len);
switch(rlen){
case 0x01:
// GROUPING:
//printf("ASF_parser: warning! grouping (flag=1) not yet supported!\n",len);
//printf(" total: %d \n",len);
while(len>0){
int len2=p[0];
p++;
//printf(" group part: %d bytes\n",len2);
if(len2 > len - 1) break; // Not enough data
demux_asf_read_packet(demux,p,len2,streamno,seq,x,duration,-1,keyframe);
p+=len2;
len-=len2+1;
++seq;
}
if(len!=0){
mp_msg(MSGT_DEMUX,MSGL_V,"ASF_parser: warning! groups total != len\n");
}
break;
default:
// NO GROUPING:
//printf("fragment offset: %d \n",sh->x);
if (!asf->asf_is_dvr_ms || asf->found_first_key_frame)
demux_asf_read_packet(demux,p,len,streamno,seq,time2,duration,x,keyframe);
p+=len;
break;
}
} // for segs
return 1; // success
}
mp_msg(MSGT_DEMUX,MSGL_V,"%08"PRIX64": UNKNOWN TYPE %02X %02X %02X %02X %02X...\n",(int64_t)demux->filepos,asf->packet[0],asf->packet[1],asf->packet[2],asf->packet[3],asf->packet[4]);
return 0;
}
#include "stheader.h"
extern void skip_audio_frame(sh_audio_t *sh_audio);
static void demux_seek_asf(demuxer_t *demuxer,float rel_seek_secs,float audio_delay,int flags){
struct asf_priv* asf = demuxer->priv;
demux_stream_t *d_audio=demuxer->audio;
demux_stream_t *d_video=demuxer->video;
sh_audio_t *sh_audio=d_audio->sh;
// sh_video_t *sh_video=d_video->sh;
//FIXME: OFF_T - didn't test ASF case yet (don't have a large asf...)
//FIXME: reports good or bad to steve@daviesfam.org please
//================= seek in ASF ==========================
float p_rate=asf->packetrate; // packets / sec
off_t rel_seek_packs=(flags&SEEK_FACTOR)? // FIXME: int may be enough?
(rel_seek_secs*(demuxer->movi_end-demuxer->movi_start)/asf->packetsize):
(rel_seek_secs*p_rate);
off_t rel_seek_bytes=rel_seek_packs*asf->packetsize;
off_t newpos;
//printf("ASF: packs: %d duration: %d \n",(int)fileh.packets,*((int*)&fileh.duration));
// printf("ASF_seek: %d secs -> %d packs -> %d bytes \n",
// rel_seek_secs,rel_seek_packs,rel_seek_bytes);
newpos=((flags&SEEK_ABSOLUTE)?demuxer->movi_start:demuxer->filepos)+rel_seek_bytes;
if(newpos<0 || newpos<demuxer->movi_start) newpos=demuxer->movi_start;
// printf("\r -- asf: newpos=%d -- \n",newpos);
stream_seek(demuxer->stream,newpos);
if (asf->asf_is_dvr_ms) asf->dvr_last_vid_pts = 0.0f;
if (d_video->id >= 0)
ds_fill_buffer(d_video);
if(sh_audio){
ds_fill_buffer(d_audio);
}
if (d_video->id >= 0)
while(1){
if(sh_audio && !d_audio->eof){
float a_pts=d_audio->pts;
a_pts+=(ds_tell_pts(d_audio)-sh_audio->a_in_buffer_len)/(float)sh_audio->i_bps;
// sync audio:
if (d_video->pts > a_pts){
skip_audio_frame(sh_audio);
// if(!ds_fill_buffer(d_audio)) sh_audio=NULL; // skip audio. EOF?
continue;
}
}
if(d_video->flags&1) break; // found a keyframe!
if(!ds_fill_buffer(d_video)) break; // skip frame. EOF?
}
}
static int demux_asf_control(demuxer_t *demuxer,int cmd, void *arg){
struct asf_priv* asf = demuxer->priv;
/* demux_stream_t *d_audio=demuxer->audio;
demux_stream_t *d_video=demuxer->video;
sh_audio_t *sh_audio=d_audio->sh;
sh_video_t *sh_video=d_video->sh;
*/
switch(cmd) {
case DEMUXER_CTRL_GET_TIME_LENGTH:
*((double *)arg)=(double)(asf->movielength);
return DEMUXER_CTRL_OK;
case DEMUXER_CTRL_GET_PERCENT_POS:
return DEMUXER_CTRL_DONTKNOW;
default:
return DEMUXER_CTRL_NOTIMPL;
}
}
static demuxer_t* demux_open_asf(demuxer_t* demuxer)
{
struct asf_priv* asf = demuxer->priv;
sh_audio_t *sh_audio=NULL;
sh_video_t *sh_video=NULL;
//---- ASF header:
if(!asf) return NULL;
init_priv(asf);
if (!read_asf_header(demuxer,asf))
return NULL;
stream_reset(demuxer->stream);
stream_seek(demuxer->stream,demuxer->movi_start);
// demuxer->idx_pos=0;
// demuxer->endpos=avi_header.movi_end;
if(demuxer->video->id != -2) {
if(!ds_fill_buffer(demuxer->video)){
mp_msg(MSGT_DEMUXER,MSGL_WARN,"ASF: " MSGTR_MissingVideoStream);
demuxer->video->sh=NULL;
//printf("ASF: missing video stream!? contact the author, it may be a bug :(\n");
} else {
sh_video=demuxer->video->sh;sh_video->ds=demuxer->video;
sh_video->fps=1000.0f; sh_video->frametime=0.001f;
if (asf->asf_is_dvr_ms) {
sh_video->bih->biWidth = 0;
sh_video->bih->biHeight = 0;
}
}
}
if(demuxer->audio->id!=-2){
mp_msg(MSGT_DEMUXER,MSGL_V,MSGTR_ASFSearchingForAudioStream,demuxer->audio->id);
if(!ds_fill_buffer(demuxer->audio)){
mp_msg(MSGT_DEMUXER,MSGL_INFO,"ASF: " MSGTR_MissingAudioStream);
demuxer->audio->sh=NULL;
} else {
sh_audio=demuxer->audio->sh;sh_audio->ds=demuxer->audio;
sh_audio->format=sh_audio->wf->wFormatTag;
}
}
if(!demuxer->stream->seek)
demuxer->seekable=0;
return demuxer;
}
static void demux_close_asf(demuxer_t *demuxer) {
struct asf_priv* asf = demuxer->priv;
if (!asf) return;
if (asf->aud_repdata_sizes)
free(asf->aud_repdata_sizes);
if (asf->vid_repdata_sizes)
free(asf->vid_repdata_sizes);
free(asf);
}
const demuxer_desc_t demuxer_desc_asf = {
"ASF demuxer",
"asf",
"ASF",
"A'rpi",
"ASF, WMV, WMA",
DEMUXER_TYPE_ASF,
1, // safe autodetect
asf_check_header,
demux_asf_fill_buffer,
demux_open_asf,
demux_close_asf,
demux_seek_asf,
demux_asf_control
};
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