mpv/libmpdemux/demux_mpg.c

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// MPG/VOB file parser for DEMUXER v2.5 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.h"
#include "demuxer.h"
#include "parse_es.h"
#include "stheader.h"
#include "mp3_hdr.h"
//#define MAX_PS_PACKETSIZE 2048
#define MAX_PS_PACKETSIZE (224*1024)
#define UNKNOWN 0
#define VIDEO_MPEG1 0x10000001
#define VIDEO_MPEG2 0x10000002
#define VIDEO_MPEG4 0x10000004
#define VIDEO_H264 0x10000005
#define AUDIO_MP2 0x50
#define AUDIO_A52 0x2000
#define AUDIO_LPCM_BE 0x10001
#define AUDIO_AAC mmioFOURCC('M', 'P', '4', 'A')
typedef struct mpg_demuxer {
float last_pts;
float final_pts;
int has_valid_timestamps;
unsigned int es_map[0x40]; //es map of stream types (associated to the pes id) from 0xb0 to 0xef
int num_a_streams;
int a_stream_ids[MAX_A_STREAMS];
} mpg_demuxer_t;
static int mpeg_pts_error=0;
static int parse_psm(demuxer_t *demux, int len) {
unsigned char c, id, type;
unsigned int plen, prog_len, es_map_len;
mpg_demuxer_t *priv = (mpg_demuxer_t *) demux->priv;
mp_dbg(MSGT_DEMUX,MSGL_V, "PARSE_PSM, len=%d\n", len);
if(! len)
return 0;
c = stream_read_char(demux->stream);
if(! (c & 0x80)) {
stream_skip(demux->stream, len - 1); //not yet valid, discard
return 0;
}
stream_skip(demux->stream, 1);
prog_len = stream_read_word(demux->stream); //length of program descriptors
stream_skip(demux->stream, prog_len); //.. that we ignore
es_map_len = stream_read_word(demux->stream); //length of elementary streams map
es_map_len = min(es_map_len, len - prog_len - 8); //sanity check
while(es_map_len > 0) {
type = stream_read_char(demux->stream);
id = stream_read_char(demux->stream);
if(id >= 0xB0 && id <= 0xEF && priv) {
int idoffset = id - 0xB0;
switch(type) {
case 0x1:
priv->es_map[idoffset] = VIDEO_MPEG1;
break;
case 0x2:
priv->es_map[idoffset] = VIDEO_MPEG2;
break;
case 0x3:
case 0x4:
priv->es_map[idoffset] = AUDIO_MP2;
break;
case 0x0f:
case 0x11:
priv->es_map[idoffset] = AUDIO_AAC;
break;
case 0x10:
priv->es_map[idoffset] = VIDEO_MPEG4;
break;
case 0x1b:
priv->es_map[idoffset] = VIDEO_H264;
break;
case 0x81:
priv->es_map[idoffset] = AUDIO_A52;
break;
}
mp_dbg(MSGT_DEMUX,MSGL_V, "PSM ES, id=0x%x, type=%x, stype: %x\n", id, type, priv->es_map[idoffset]);
}
plen = stream_read_word(demux->stream); //length of elementary stream descriptors
plen = min(plen, es_map_len); //sanity check
stream_skip(demux->stream, plen); //skip descriptors for now
es_map_len -= 4 + plen;
}
stream_skip(demux->stream, 4); //skip crc32
return 1;
}
/// Open an mpg physical stream
int demux_mpg_open(demuxer_t* demuxer) {
stream_t *s = demuxer->stream;
off_t pos = stream_tell(s);
off_t end_seq_start = demuxer->movi_end-500000; // 500000 is a wild guess
float half_pts = 0.0;
mpg_demuxer_t* mpg_d;
if (!ds_fill_buffer(demuxer->video)) return 0;
mpg_d = (mpg_demuxer_t*)calloc(1,sizeof(mpg_demuxer_t));
demuxer->priv = mpg_d;
mpg_d->final_pts = 0.0;
mpg_d->has_valid_timestamps = 1;
mpg_d->num_a_streams = 0;
if (demuxer->seekable && stream_tell(demuxer->stream) < end_seq_start) {
stream_seek(s,(pos + end_seq_start / 2));
while ((!s->eof) && ds_fill_buffer(demuxer->video) && half_pts == 0.0) {
half_pts = mpg_d->last_pts;
}
stream_seek(s,end_seq_start);
while ((!s->eof) && ds_fill_buffer(demuxer->video)) {
if (mpg_d->final_pts < mpg_d->last_pts) mpg_d->final_pts = mpg_d->last_pts;
}
// educated guess about validity of timestamps
if (mpg_d->final_pts > 3 * half_pts || mpg_d->final_pts < 1.5 * half_pts) {
mpg_d->has_valid_timestamps = 0;
}
ds_free_packs(demuxer->audio);
ds_free_packs(demuxer->video);
demuxer->stream->eof=0; // clear eof flag
demuxer->video->eof=0;
demuxer->audio->eof=0;
stream_seek(s,pos);
ds_fill_buffer(demuxer->video);
}
return 1;
}
void demux_close_mpg(demuxer_t* demuxer) {
mpg_demuxer_t* mpg_d = demuxer->priv;
if (mpg_d) free(mpg_d);
}
static unsigned int read_mpeg_timestamp(stream_t *s,int c){
int d,e;
unsigned int pts;
d=stream_read_word(s);
e=stream_read_word(s);
if( ((c&1)!=1) || ((d&1)!=1) || ((e&1)!=1) ){
++mpeg_pts_error;
return 0; // invalid pts
}
pts=(((c>>1)&7)<<30)|((d>>1)<<15)|(e>>1);
mp_dbg(MSGT_DEMUX,MSGL_DBG3,"{%d}",pts);
return pts;
}
static void new_audio_stream(demuxer_t *demux, int aid){
if(!demux->a_streams[aid]){
mpg_demuxer_t *mpg_d=(mpg_demuxer_t*)demux->priv;
sh_audio_t* sh_a;
new_sh_audio(demux,aid);
sh_a = (sh_audio_t*)demux->a_streams[aid];
switch(aid & 0xE0){ // 1110 0000 b (high 3 bit: type low 5: id)
case 0x00: sh_a->format=0x50;break; // mpeg
case 0xA0: sh_a->format=0x10001;break; // dvd pcm
case 0x80: if((aid & 0xF8) == 0x88) sh_a->format=0x2001;//dts
else sh_a->format=0x2000;break; // ac3
}
if (mpg_d) mpg_d->a_stream_ids[mpg_d->num_a_streams++] = aid;
}
if(demux->audio->id==-1) demux->audio->id=aid;
}
static int demux_mpg_read_packet(demuxer_t *demux,int id){
int d;
int len;
unsigned char c=0;
unsigned int pts=0;
unsigned int dts=0;
demux_stream_t *ds=NULL;
mpg_demuxer_t *priv = (mpg_demuxer_t *) demux->priv;
mp_dbg(MSGT_DEMUX,MSGL_DBG3,"demux_read_packet: %X\n",id);
// if(id==0x1F0){
// demux->synced=0; // force resync after 0x1F0
// return -1;
//}
// if(id==0x1BA) packet_start_pos=stream_tell(demux->stream);
if(id<0x1BC || id>=0x1F0) return -1;
if(id==0x1BE) return -1; // padding stream
if(id==0x1BF) return -1; // private2
len=stream_read_word(demux->stream);
mp_dbg(MSGT_DEMUX,MSGL_DBG3,"PACKET len=%d",len);
// if(len==62480){ demux->synced=0;return -1;} /* :) */
if(len==0 || len>MAX_PS_PACKETSIZE){
mp_dbg(MSGT_DEMUX,MSGL_DBG2,"Invalid PS packet len: %d\n",len);
return -2; // invalid packet !!!!!!
}
mpeg_pts_error=0;
if(id==0x1BC) {
parse_psm(demux, len);
return 0;
}
while(len>0){ // Skip stuFFing bytes
c=stream_read_char(demux->stream);--len;
if(c!=0xFF)break;
}
if((c>>6)==1){ // Read (skip) STD scale & size value
// printf(" STD_scale=%d",(c>>5)&1);
d=((c&0x1F)<<8)|stream_read_char(demux->stream);
len-=2;
// printf(" STD_size=%d",d);
c=stream_read_char(demux->stream);
}
// Read System-1 stream timestamps:
if((c>>4)==2){
pts=read_mpeg_timestamp(demux->stream,c);
len-=4;
} else
if((c>>4)==3){
pts=read_mpeg_timestamp(demux->stream,c);
c=stream_read_char(demux->stream);
if((c>>4)!=1) pts=0; //printf("{ERROR4}");
dts=read_mpeg_timestamp(demux->stream,c);
len-=4+1+4;
} else
if((c>>6)==2){
int pts_flags;
int hdrlen;
// System-2 (.VOB) stream:
if((c>>4)&3) {
mp_msg(MSGT_DEMUX,MSGL_WARN,MSGTR_EncryptedVOB);
}
c=stream_read_char(demux->stream); pts_flags=c>>6;
c=stream_read_char(demux->stream); hdrlen=c;
len-=2;
mp_dbg(MSGT_DEMUX,MSGL_DBG3," hdrlen=%d (len=%d)",hdrlen,len);
if(hdrlen>len){ mp_msg(MSGT_DEMUX,MSGL_V,"demux_mpg: invalid header length \n"); return -1;}
if(pts_flags==2 && hdrlen>=5){
c=stream_read_char(demux->stream);
pts=read_mpeg_timestamp(demux->stream,c);
len-=5;hdrlen-=5;
} else
if(pts_flags==3 && hdrlen>=10){
c=stream_read_char(demux->stream);
pts=read_mpeg_timestamp(demux->stream,c);
c=stream_read_char(demux->stream);
dts=read_mpeg_timestamp(demux->stream,c);
len-=10;hdrlen-=10;
}
len-=hdrlen;
if(hdrlen>0) stream_skip(demux->stream,hdrlen); // skip header bytes
//============== DVD Audio sub-stream ======================
if(id==0x1BD){
int aid, rawa52 = 0;
off_t tmppos;
unsigned int tmp;
tmppos = stream_tell(demux->stream);
tmp = stream_read_word(demux->stream);
stream_seek(demux->stream, tmppos);
/// vdr stores A52 without the 4 header bytes, so we have to check this condition first
if(tmp == 0x0B77) {
aid = 128;
rawa52 = 1;
}
else {
aid=stream_read_char(demux->stream);--len;
if(len<3) return -1; // invalid audio packet
}
// AID:
// 0x20..0x3F subtitle
// 0x80..0x9F AC3 audio
// 0xA0..0xBF PCM audio
if((aid & 0xE0) == 0x20){
// subtitle:
aid&=0x1F;
if(!demux->s_streams[aid]){
mp_msg(MSGT_DEMUX,MSGL_V,"==> Found subtitle: %d\n",aid);
demux->s_streams[aid]=1;
}
if(demux->sub->id==aid){
ds=demux->sub;
}
} else if((aid & 0xC0) == 0x80 || (aid & 0xE0) == 0x00) {
// aid=128+(aid&0x7F);
// aid=0x80..0xBF
new_audio_stream(demux, aid);
if(demux->audio->id==aid){
int type;
ds=demux->audio;
if(!ds->sh) ds->sh=demux->a_streams[aid];
// READ Packet: Skip additional audio header data:
if(!rawa52) {
c=stream_read_char(demux->stream);//num of frames
type=stream_read_char(demux->stream);//startpos hi
type=(type<<8)|stream_read_char(demux->stream);//startpos lo
// printf("\r[%02X][%04X]",c,type);
len-=3;
}
if((aid&0xE0)==0xA0 && len>=3){
unsigned char* hdr;
// save audio header as codecdata!
if(!((sh_audio_t*)(ds->sh))->codecdata_len){
((sh_audio_t*)(ds->sh))->codecdata=malloc(3);
((sh_audio_t*)(ds->sh))->codecdata_len=3;
}
hdr=((sh_audio_t*)(ds->sh))->codecdata;
// read LPCM header:
// emphasis[1], mute[1], rvd[1], frame number[5]:
hdr[0]=stream_read_char(demux->stream);
// printf(" [%01X:%02d]",c>>5,c&31);
// quantization[2],freq[2],rvd[1],channels[3]
hdr[1]=stream_read_char(demux->stream);
// printf("[%01X:%01X] ",c>>4,c&15);
// dynamic range control (0x80=off):
hdr[2]=stream_read_char(demux->stream);
// printf("[%02X] ",c);
len-=3;
if(len<=0) mp_msg(MSGT_DEMUX,MSGL_V,"End of packet while searching for PCM header\n");
}
// printf(" \n");
} // if(demux->audio->id==aid)
} else mp_msg(MSGT_DEMUX,MSGL_V,"Unknown 0x1BD substream: 0x%02X \n",aid);
} //if(id==0x1BD)
} else {
if(c!=0x0f){
mp_msg(MSGT_DEMUX,MSGL_V," {ERROR5,c=%d} \n",c);
return -1; // invalid packet !!!!!!
}
}
if(mpeg_pts_error) mp_msg(MSGT_DEMUX,MSGL_V," {PTS_err:%d} \n",mpeg_pts_error);
mp_dbg(MSGT_DEMUX,MSGL_DBG3," => len=%d\n",len);
// if(len<=0 || len>MAX_PS_PACKETSIZE) return -1; // Invalid packet size
if(len<=0 || len>MAX_PS_PACKETSIZE){
mp_dbg(MSGT_DEMUX,MSGL_DBG2,"Invalid PS data len: %d\n",len);
return -1; // invalid packet !!!!!!
}
if(id>=0x1C0 && id<=0x1DF){
// mpeg audio
int aid=id-0x1C0;
new_audio_stream(demux, aid);
if(demux->audio->id==aid){
ds=demux->audio;
if(!ds->sh) ds->sh=demux->a_streams[aid];
if(priv && ds->sh) {
sh_audio_t *sh = (sh_audio_t *)ds->sh;
if(priv->es_map[id - 0x1B0])
sh->format = priv->es_map[id - 0x1B0];
mp_dbg(MSGT_DEMUX,MSGL_DBG2,"ASSIGNED TO STREAM %d CODEC %x\n", id, priv->es_map[id - 0x1B0]);
}
}
} else
if(id>=0x1E0 && id<=0x1EF){
// mpeg video
int aid=id-0x1E0;
if(!demux->v_streams[aid]) new_sh_video(demux,aid);
if(demux->video->id==-1) demux->video->id=aid;
if(demux->video->id==aid){
ds=demux->video;
if(!ds->sh) ds->sh=demux->v_streams[aid];
if(priv && ds->sh) {
sh_video_t *sh = (sh_video_t *)ds->sh;
if(priv->es_map[id - 0x1B0]) {
sh->format = priv->es_map[id - 0x1B0];
mp_dbg(MSGT_DEMUX,MSGL_DBG2,"ASSIGNED TO STREAM %d CODEC %x\n", id, priv->es_map[id - 0x1B0]);
}
}
}
}
if(ds){
mp_dbg(MSGT_DEMUX,MSGL_DBG2,"DEMUX_MPG: Read %d data bytes from packet %04X\n",len,id);
// printf("packet start = 0x%X \n",stream_tell(demux->stream)-packet_start_pos);
ds_read_packet(ds,demux->stream,len,pts/90000.0f,demux->filepos,0);
if (demux->priv) ((mpg_demuxer_t*)demux->priv)->last_pts = pts/90000.0f;
// if(ds==demux->sub) parse_dvdsub(ds->last->buffer,ds->last->len);
return 1;
}
mp_dbg(MSGT_DEMUX,MSGL_DBG2,"DEMUX_MPG: Skipping %d data bytes from packet %04X\n",len,id);
if(len<=2356) stream_skip(demux->stream,len);
return 0;
}
static int num_elementary_packets100=0;
static int num_elementary_packets101=0;
static int num_elementary_packets12x=0;
static int num_elementary_packets1B6=0;
static int num_elementary_packetsPES=0;
static int num_h264_slice=0; //combined slice
static int num_h264_dpa=0; //DPA Slice
static int num_h264_dpb=0; //DPB Slice
static int num_h264_dpc=0; //DPC Slice
static int num_h264_idr=0; //IDR Slice
static int num_h264_sps=0;
static int num_h264_pps=0;
static int num_mp3audio_packets=0;
int demux_mpg_probe(demuxer_t *demuxer) {
int pes=1;
int tmp;
off_t tmppos;
int file_format = DEMUXER_TYPE_UNKNOWN;
tmppos=stream_tell(demuxer->stream);
tmp=stream_read_dword(demuxer->stream);
if(tmp==0x1E0 || tmp==0x1C0) {
tmp=stream_read_word(demuxer->stream);
if(tmp>1 && tmp<=2048) pes=0; // demuxer->synced=3; // PES...
}
stream_seek(demuxer->stream,tmppos);
num_elementary_packets100=0;
num_elementary_packets101=0;
num_elementary_packets1B6=0;
num_elementary_packets12x=0;
num_elementary_packetsPES=0;
num_h264_slice=0; //combined slice
num_h264_dpa=0; //DPA Slice
num_h264_dpb=0; //DPB Slice
num_h264_dpc=0; //DPC Slice
num_h264_idr=0; //IDR Slice
num_h264_sps=0;
num_h264_pps=0;
num_mp3audio_packets=0;
if(demux_mpg_open(demuxer))
file_format=DEMUXER_TYPE_MPEG_PS;
else {
mp_msg(MSGT_DEMUX,MSGL_V,"MPEG packet stats: p100: %d p101: %d p1B6: %d p12x: %d sli: %d a: %d b: %d c: %d idr: %d sps: %d pps: %d PES: %d MP3: %d, synced: %d\n",
num_elementary_packets100,num_elementary_packets101,
num_elementary_packets1B6,num_elementary_packets12x,
num_h264_slice, num_h264_dpa,
num_h264_dpb, num_h264_dpc=0,
num_h264_idr, num_h264_sps=0,
num_h264_pps,
num_elementary_packetsPES,num_mp3audio_packets, demuxer->synced);
//MPEG packet stats: p100: 458 p101: 458 PES: 0 MP3: 1103 (.m2v)
if(num_mp3audio_packets>50 && num_mp3audio_packets>2*num_elementary_packets100
&& abs(num_elementary_packets100-num_elementary_packets101)>2)
return file_format;
// some hack to get meaningfull error messages to our unhappy users:
if(num_elementary_packets100>=2 && num_elementary_packets101>=2 &&
abs(num_elementary_packets101+8-num_elementary_packets100)<16) {
if(num_elementary_packetsPES>=4 && num_elementary_packetsPES>=num_elementary_packets100-4) {
return file_format;
}
file_format=DEMUXER_TYPE_MPEG_ES; // <-- hack is here :)
} else
#if 1
// fuzzy mpeg4-es detection. do NOT enable without heavy testing of mpeg formats detection!
if(num_elementary_packets1B6>3 && num_elementary_packets12x>=1 &&
num_elementary_packetsPES==0 && num_elementary_packets100<=num_elementary_packets12x &&
demuxer->synced<2) {
file_format=DEMUXER_TYPE_MPEG4_ES;
} else
#endif
#if 1
// fuzzy h264-es detection. do NOT enable without heavy testing of mpeg formats detection!
if((num_h264_slice>3 || (num_h264_dpa>3 && num_h264_dpb>3 && num_h264_dpc>3)) &&
/* FIXME num_h264_sps>=1 && */ num_h264_pps>=1 && num_h264_idr>=1 &&
num_elementary_packets1B6==0 && num_elementary_packetsPES==0 &&
demuxer->synced<2) {
file_format=DEMUXER_TYPE_H264_ES;
} else
#endif
{
if(demuxer->synced==2)
mp_msg(MSGT_DEMUXER,MSGL_ERR,"MPEG: " MSGTR_MissingVideoStreamBug);
else
mp_msg(MSGT_DEMUXER,MSGL_V,MSGTR_NotSystemStream);
}
}
return file_format;
}
int demux_mpg_es_fill_buffer(demuxer_t *demux){
// Elementary video stream
if(demux->stream->eof) return 0;
demux->filepos=stream_tell(demux->stream);
ds_read_packet(demux->video,demux->stream,STREAM_BUFFER_SIZE,0,demux->filepos,0);
return 1;
}
int demux_mpg_fill_buffer(demuxer_t *demux){
unsigned int head=0;
int skipped=0;
int max_packs=256; // 512kbyte
int ret=0;
// System stream
do{
demux->filepos=stream_tell(demux->stream);
head=stream_read_dword(demux->stream);
if((head&0xFFFFFF00)!=0x100){
// sync...
demux->filepos-=skipped;
while(1){
int c=stream_read_char(demux->stream);
if(c<0) break; //EOF
head<<=8;
if(head!=0x100){
head|=c;
if(mp_check_mp3_header(head)) ++num_mp3audio_packets;
++skipped; //++demux->filepos;
continue;
}
head|=c;
break;
}
demux->filepos+=skipped;
}
if(stream_eof(demux->stream)) break;
// sure: head=0x000001XX
mp_dbg(MSGT_DEMUX,MSGL_DBG4,"*** head=0x%X\n",head);
if(demux->synced==0){
if(head==0x1BA) demux->synced=1; //else
// if(head==0x1BD || (head>=0x1C0 && head<=0x1EF)) demux->synced=3; // PES?
} else
if(demux->synced==1){
if(head==0x1BB || head==0x1BD || (head>=0x1C0 && head<=0x1EF)){
demux->synced=2;
mp_msg(MSGT_DEMUX,MSGL_V,"system stream synced at 0x%X (%d)!\n",demux->filepos,demux->filepos);
num_elementary_packets100=0; // requires for re-sync!
num_elementary_packets101=0; // requires for re-sync!
} else demux->synced=0;
} // else
if(demux->synced>=2){
ret=demux_mpg_read_packet(demux,head);
if(!ret)
if(--max_packs==0){
demux->stream->eof=1;
mp_msg(MSGT_DEMUX,MSGL_ERR,MSGTR_DoesntContainSelectedStream);
return 0;
}
if(demux->synced==3) demux->synced=(ret==1)?2:0; // PES detect
} else {
if(head>=0x100 && head<0x1B0){
if(head==0x100) ++num_elementary_packets100; else
if(head==0x101) ++num_elementary_packets101; else
if(head>=0x120 && head<=0x12F) ++num_elementary_packets12x;
if((head&~0x60) == 0x101) ++num_h264_slice; else
if((head&~0x60) == 0x102) ++num_h264_dpa; else
if((head&~0x60) == 0x103) ++num_h264_dpb; else
if((head&~0x60) == 0x104) ++num_h264_dpc; else
if((head&~0x60) == 0x105 && head != 0x105) ++num_h264_idr; else
if((head&~0x60) == 0x107 && head != 0x107) ++num_h264_sps; else
if((head&~0x60) == 0x108 && head != 0x108) ++num_h264_pps;
mp_msg(MSGT_DEMUX,MSGL_DBG3,"Opps... elementary video packet found: %03X\n",head);
} else
if((head>=0x1C0 && head<0x1F0) || head==0x1BD){
++num_elementary_packetsPES;
mp_msg(MSGT_DEMUX,MSGL_DBG3,"Opps... PES packet found: %03X\n",head);
} else
if(head==0x1B6) ++num_elementary_packets1B6;
#if 1
if( ( (num_elementary_packets100>50 && num_elementary_packets101>50) ||
(num_elementary_packetsPES>50) ) && skipped>4000000){
mp_msg(MSGT_DEMUX,MSGL_V,"sync_mpeg_ps: seems to be ES/PES stream...\n");
demux->stream->eof=1;
break;
}
if(num_mp3audio_packets>100 && num_elementary_packets100<10){
mp_msg(MSGT_DEMUX,MSGL_V,"sync_mpeg_ps: seems to be MP3 stream...\n");
demux->stream->eof=1;
break;
}
#endif
}
} while(ret!=1);
mp_dbg(MSGT_DEMUX,MSGL_DBG2,"demux: %d bad bytes skipped\n",skipped);
if(demux->stream->eof){
mp_msg(MSGT_DEMUX,MSGL_V,"MPEG Stream reached EOF\n");
return 0;
}
return 1;
}
extern void resync_audio_stream(sh_audio_t *sh_audio);
extern void skip_audio_frame(sh_audio_t *sh_audio);
void demux_seek_mpg(demuxer_t *demuxer,float rel_seek_secs,int flags){
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;
mpg_demuxer_t *mpg_d=(mpg_demuxer_t*)demuxer->priv;
int precision = 1;
float oldpts = 0;
off_t oldpos = demuxer->filepos;
float newpts = 0;
off_t newpos = (flags & 1) ? demuxer->movi_start : oldpos;
if(mpg_d)
oldpts = mpg_d->last_pts;
newpts = (flags & 1) ? 0.0 : oldpts;
//================= seek in MPEG ==========================
//calculate the pts to seek to
if(flags & 2) {
if (mpg_d && mpg_d->final_pts > 0.0)
newpts += mpg_d->final_pts * rel_seek_secs;
else
newpts += rel_seek_secs * (demuxer->movi_end - demuxer->movi_start) * oldpts / oldpos;
} else
newpts += rel_seek_secs;
if (newpts < 0) newpts = 0;
if(flags&2){
// float seek 0..1
newpos+=(demuxer->movi_end-demuxer->movi_start)*rel_seek_secs;
} else {
// time seek (secs)
if (mpg_d && mpg_d->has_valid_timestamps) {
if (mpg_d->final_pts > 0.0)
newpos += rel_seek_secs * (demuxer->movi_end - demuxer->movi_start) / mpg_d->final_pts;
else if (oldpts > 0.0)
newpos += rel_seek_secs * (oldpos - demuxer->movi_start) / oldpts;
} else if(!sh_video || !sh_video->i_bps) // unspecified or VBR
newpos+=2324*75*rel_seek_secs; // 174.3 kbyte/sec
else
newpos+=sh_video->i_bps*rel_seek_secs;
}
while (1) {
if(newpos<demuxer->movi_start){
if(demuxer->stream->type!=STREAMTYPE_VCD) demuxer->movi_start=0; // for VCD
if(newpos<demuxer->movi_start) newpos=demuxer->movi_start;
}
#ifdef _LARGEFILE_SOURCE
newpos&=~((long long)STREAM_BUFFER_SIZE-1); /* sector boundary */
#else
newpos&=~(STREAM_BUFFER_SIZE-1); /* sector boundary */
#endif
stream_seek(demuxer->stream,newpos);
// re-sync video:
videobuf_code_len=0; // reset ES stream buffer
ds_fill_buffer(d_video);
if(sh_audio){
ds_fill_buffer(d_audio);
resync_audio_stream(sh_audio);
}
while(1){
int i;
if(sh_audio && !d_audio->eof && d_video->pts && d_audio->pts){
float a_pts=d_audio->pts;
a_pts+=(ds_tell_pts(d_audio)-sh_audio->a_in_buffer_len)/(float)sh_audio->i_bps;
if(d_video->pts>a_pts){
skip_audio_frame(sh_audio); // sync audio
continue;
}
}
i=sync_video_packet(d_video);
if(sh_video->format == 0x10000004) { //mpeg4
if(i==0x1B6) { //vop (frame) startcode
int pos = videobuf_len;
if(!read_video_packet(d_video)) break; // EOF
if((videobuffer[pos+4] & 0x3F) == 0) break; //I-frame
}
} else if(sh_video->format == 0x10000005){ //h264
if((i & ~0x60) == 0x101 || (i & ~0x60) == 0x102 || (i & ~0x60) == 0x105) break;
} else { //default mpeg1/2
if(i==0x1B3 || i==0x1B8) break; // found it!
}
if(!i || !skip_video_packet(d_video)) break; // EOF?
}
if(!mpg_d)
break;
if (!precision || abs(newpts - mpg_d->last_pts) < 0.5 || (mpg_d->last_pts == oldpts)) break;
if ((newpos - oldpos) * (mpg_d->last_pts - oldpts) < 0) { // invalid timestamps
mpg_d->has_valid_timestamps = 0;
break;
}
precision--;
//prepare another seek because we are off by more than 0.5s
if(mpg_d) {
newpos += (newpts - mpg_d->last_pts) * (newpos - oldpos) / (mpg_d->last_pts - oldpts);
ds_free_packs(d_audio);
ds_free_packs(d_video);
demuxer->stream->eof=0; // clear eof flag
d_video->eof=0;
d_audio->eof=0;
}
}
}
int demux_mpg_control(demuxer_t *demuxer,int cmd, void *arg){
demux_stream_t *d_video=demuxer->video;
sh_video_t *sh_video=d_video->sh;
mpg_demuxer_t *mpg_d=(mpg_demuxer_t*)demuxer->priv;
switch(cmd) {
case DEMUXER_CTRL_GET_TIME_LENGTH:
if (mpg_d && mpg_d->has_valid_timestamps) {
*((unsigned long *)arg)=(long)mpg_d->final_pts;
return DEMUXER_CTRL_GUESS;
}
return DEMUXER_CTRL_DONTKNOW;
case DEMUXER_CTRL_GET_PERCENT_POS:
if (mpg_d && mpg_d->has_valid_timestamps && mpg_d->final_pts > 0.0) {
*((int *)arg)=(int)(100 * mpg_d->last_pts / mpg_d->final_pts);
return DEMUXER_CTRL_OK;
}
return DEMUXER_CTRL_DONTKNOW;
case DEMUXER_CTRL_SWITCH_AUDIO:
if (mpg_d && mpg_d->num_a_streams > 1 && demuxer->audio && demuxer->audio->sh) {
demux_stream_t *d_audio = demuxer->audio;
sh_audio_t *sh_audio = d_audio->sh;
sh_audio_t *sh_a;
int i;
if (*((int*)arg) < 0)
{
for (i = 0; i < mpg_d->num_a_streams; i++) {
if (d_audio->id == mpg_d->a_stream_ids[i]) break;
}
do {
i = (i+1) % mpg_d->num_a_streams;
sh_a = (sh_audio_t*)demuxer->a_streams[mpg_d->a_stream_ids[i]];
} while (sh_a->format != sh_audio->format);
}
else {
for (i = 0; i < mpg_d->num_a_streams; i++)
if (*((int*)arg) == mpg_d->a_stream_ids[i]) break;
if (i < mpg_d->num_a_streams)
sh_a = (sh_audio_t*)demuxer->a_streams[*((int*)arg)];
if (sh_a->format != sh_audio->format)
i = mpg_d->num_a_streams;
}
if (i < mpg_d->num_a_streams && d_audio->id != mpg_d->a_stream_ids[i]) {
d_audio->id = mpg_d->a_stream_ids[i];
d_audio->sh = sh_a;
ds_free_packs(d_audio);
}
}
*((int*)arg) = demuxer->audio->id;
return DEMUXER_CTRL_OK;
default:
return DEMUXER_CTRL_NOTIMPL;
}
}