1 /*****************************************************************************
2 * mpeg_system.c: TS, PS and PES management
3 *****************************************************************************
4 * Copyright (C) 1998, 1999, 2000 VideoLAN
5 * $Id: mpeg_system.c,v 1.31 2001/02/08 01:34:42 stef Exp $
9 * This program is free software; you can redistribute it and/or modify
10 * it under the terms of the GNU General Public License as published by
11 * the Free Software Foundation; either version 2 of the License, or
12 * (at your option) any later version.
14 * This program is distributed in the hope that it will be useful,
15 * but WITHOUT ANY WARRANTY; without even the implied warranty of
16 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
17 * GNU General Public License for more details.
19 * You should have received a copy of the GNU General Public License
20 * along with this program; if not, write to the Free Software
21 * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111, USA.
22 *****************************************************************************/
24 /*****************************************************************************
26 *****************************************************************************/
38 #include "stream_control.h"
39 #include "input_ext-intf.h"
40 #include "input_ext-dec.h"
43 #include "mpeg_system.h"
45 #include "main.h" /* AC3/MPEG channel, SPU channel */
47 /*****************************************************************************
49 *****************************************************************************/
53 * PES Packet management
56 /*****************************************************************************
58 *****************************************************************************
59 * Small utility function used to parse discontinuous headers safely. Copies
60 * i_buf_len bytes of data to a buffer and returns the size copied.
61 * This is a variation on the theme of input_ext-dec.h:GetChunk().
62 *****************************************************************************/
63 static __inline__ size_t MoveChunk( byte_t * p_dest,
64 data_packet_t ** pp_data_src,
68 ptrdiff_t i_available;
70 if( (i_available = (*pp_data_src)->p_payload_end - *pp_src)
74 memcpy( p_dest, *pp_src, i_buf_len );
80 size_t i_init_len = i_buf_len;
85 memcpy( p_dest, *pp_src, i_available );
86 *pp_data_src = (*pp_data_src)->p_next;
87 i_buf_len -= i_available;
88 p_dest += i_available;
89 if( *pp_data_src == NULL )
92 return( i_init_len - i_buf_len );
94 *pp_src = (*pp_data_src)->p_payload_start;
96 while( (i_available = (*pp_data_src)->p_payload_end - *pp_src)
102 memcpy( p_dest, *pp_src, i_buf_len );
103 *pp_src += i_buf_len;
105 return( i_init_len );
109 /*****************************************************************************
111 *****************************************************************************
112 * Parse a finished PES packet and analyze its header.
113 *****************************************************************************/
114 #define PES_HEADER_SIZE 7
115 void input_ParsePES( input_thread_t * p_input, es_descriptor_t * p_es )
117 data_packet_t * p_data;
119 byte_t p_header[PES_HEADER_SIZE];
122 #define p_pes (p_es->p_pes)
124 //intf_DbgMsg("End of PES packet %p", p_pes);
126 /* Parse the header. The header has a variable length, but in order
127 * to improve the algorithm, we will read the 14 bytes we may be
129 p_data = p_pes->p_first;
130 p_byte = p_data->p_payload_start;
133 if( MoveChunk( p_header, &p_data, &p_byte, PES_HEADER_SIZE )
136 intf_WarnMsg( 3, "PES packet too short to have a header" );
137 p_input->p_plugin->pf_delete_pes( p_input->p_method_data, p_pes );
142 /* Get the PES size if defined */
143 p_es->i_pes_real_size = U16_AT(p_header + 4) + 6;
145 /* First read the 6 header bytes common to all PES packets:
146 * use them to test the PES validity */
147 if( (p_header[0] || p_header[1] || (p_header[2] != 1)) )
149 /* packet_start_code_prefix != 0x000001 */
150 intf_ErrMsg( "PES packet doesn't start with 0x000001 : data loss" );
151 p_input->p_plugin->pf_delete_pes( p_input->p_method_data, p_pes );
156 int i_pes_header_size, i_payload_size;
158 if ( p_es->i_pes_real_size &&
159 (p_es->i_pes_real_size != p_pes->i_pes_size) )
161 /* PES_packet_length is set and != total received payload */
162 /* Warn the decoder that the data may be corrupt. */
163 intf_WarnMsg( 3, "PES sizes do not match : packet corrupted" );
164 p_pes->b_messed_up = 1;
167 switch( p_es->i_stream_id )
169 case 0xBC: /* Program stream map */
170 case 0xBE: /* Padding */
171 case 0xBF: /* Private stream 2 */
174 case 0xFF: /* Program stream directory */
175 case 0xF2: /* DSMCC stream */
176 case 0xF8: /* ITU-T H.222.1 type E stream */
177 /* The payload begins immediately after the 6 bytes header, so
178 * we have finished with the parsing */
179 i_pes_header_size = 6;
183 if( (p_header[6] & 0xC0) == 0x80 )
185 /* MPEG-2 : the PES header contains at least 3 more bytes. */
187 boolean_t b_has_pts, b_has_dts;
188 byte_t p_full_header[12];
190 p_pes->b_data_alignment = p_header[6] & 0x04;
192 i_max_len = MoveChunk( p_full_header, &p_data, &p_byte, 12 );
196 "PES packet too short to have a MPEG-2 header" );
197 p_input->p_plugin->pf_delete_pes( p_input->p_method_data,
203 b_has_pts = p_full_header[0] & 0x80;
204 b_has_dts = p_full_header[0] & 0x40;
205 i_pes_header_size = p_full_header[1] + 9;
207 /* Now parse the optional header extensions */
213 "PES packet too short to have a MPEG-2 header" );
214 p_input->p_plugin->pf_delete_pes(
215 p_input->p_method_data,
220 p_pes->i_pts = input_ClockGetTS( p_input, p_es->p_pgrm,
221 ( ((mtime_t)(p_full_header[2] & 0x0E) << 29) |
222 (((mtime_t)U16_AT(p_full_header + 3) << 14) - (1 << 14)) |
223 ((mtime_t)U16_AT(p_full_header + 5) >> 1) ) );
230 "PES packet too short to have a MPEG-2 header" );
231 p_input->p_plugin->pf_delete_pes(
232 p_input->p_method_data,
237 p_pes->i_dts = input_ClockGetTS( p_input, p_es->p_pgrm,
238 ( ((mtime_t)(p_full_header[7] & 0x0E) << 29) |
239 (((mtime_t)U16_AT(p_full_header + 8) << 14)
241 ((mtime_t)U16_AT(p_full_header + 10) >> 1) ) );
247 /* Probably MPEG-1 */
248 boolean_t b_has_pts, b_has_dts;
250 i_pes_header_size = 6;
251 p_data = p_pes->p_first;
252 p_byte = p_data->p_payload_start;
253 /* Cannot fail because the previous one succeeded. */
254 MoveChunk( NULL, &p_data, &p_byte, 6 );
256 while( *p_byte == 0xFF && i_pes_header_size < 22 )
259 if( MoveChunk( NULL, &p_data, &p_byte, 1 ) != 1 )
262 "PES packet too short to have a MPEG-1 header" );
263 p_input->p_plugin->pf_delete_pes( p_input->p_method_data, p_pes );
268 if( i_pes_header_size == 22 )
270 intf_ErrMsg( "Too much MPEG-1 stuffing" );
271 p_input->p_plugin->pf_delete_pes( p_input->p_method_data, p_pes );
276 if( (*p_byte & 0xC0) == 0x40 )
278 /* Don't ask why... --Meuuh */
279 /* Erm... why ? --Sam */
280 /* Well... According to the recommendation, it is for
281 * STD_buffer_scale and STD_buffer_size. --Meuuh */
282 i_pes_header_size += 2;
283 if( MoveChunk( NULL, &p_data, &p_byte, 2 ) != 2 )
286 "PES packet too short to have a MPEG-1 header" );
287 p_input->p_plugin->pf_delete_pes( p_input->p_method_data, p_pes );
295 b_has_pts = *p_byte & 0x20;
296 b_has_dts = *p_byte & 0x10;
302 i_pes_header_size += 4;
303 if( MoveChunk( p_ts, &p_data, &p_byte, 5 ) != 5 )
306 "PES packet too short to have a MPEG-1 header" );
307 p_input->p_plugin->pf_delete_pes(
308 p_input->p_method_data, p_pes );
313 p_pes->i_pts = input_ClockGetTS( p_input, p_es->p_pgrm,
314 ( ((mtime_t)(p_ts[0] & 0x0E) << 29) |
315 (((mtime_t)U16_AT(p_ts + 1) << 14) - (1 << 14)) |
316 ((mtime_t)U16_AT(p_ts + 3) >> 1) ) );
320 i_pes_header_size += 5;
321 if( MoveChunk( p_ts, &p_data, &p_byte, 5 ) != 5 )
324 "PES packet too short to have a MPEG-1 header" );
325 p_input->p_plugin->pf_delete_pes(
326 p_input->p_method_data, p_pes );
331 p_pes->i_dts = input_ClockGetTS( p_input,
333 ( ((mtime_t)(p_ts[0] & 0x0E) << 29) |
334 (((mtime_t)U16_AT(p_ts + 1) << 14) - (1 << 14)) |
335 ((mtime_t)U16_AT(p_ts + 3) >> 1) ) );
343 if( p_es->i_stream_id == 0xbd )
345 /* With private stream 1, the first byte of the payload
346 * is a stream_private_id, so skip it. */
350 /* Now we've parsed the header, we just have to indicate in some
351 * specific data packets where the PES payload begins (renumber
352 * p_payload_start), so that the decoders can find the beginning
353 * of their data right out of the box. */
354 p_data = p_pes->p_first;
355 i_payload_size = p_data->p_payload_end
356 - p_data->p_payload_start;
357 while( i_pes_header_size > i_payload_size )
359 /* These packets are entirely filled by the PES header. */
360 i_pes_header_size -= i_payload_size;
361 p_data->p_payload_start = p_data->p_payload_end;
362 /* Go to the next data packet. */
363 if( (p_data = p_data->p_next) == NULL )
365 intf_ErrMsg( "PES header bigger than payload" );
366 p_input->p_plugin->pf_delete_pes( p_input->p_method_data,
371 i_payload_size = p_data->p_payload_end
372 - p_data->p_payload_start;
374 /* This last packet is partly header, partly payload. */
375 if( i_payload_size < i_pes_header_size )
377 intf_ErrMsg( "PES header bigger than payload" );
378 p_input->p_plugin->pf_delete_pes( p_input->p_method_data, p_pes );
382 p_data->p_payload_start += i_pes_header_size;
384 /* Now we can eventually put the PES packet in the decoder's
386 if( p_es->p_decoder_fifo != NULL )
388 input_DecodePES( p_es->p_decoder_fifo, p_pes );
392 intf_ErrMsg("No fifo to receive PES %p (who wrote this damn code ?)",
394 p_input->p_plugin->pf_delete_pes( p_input->p_method_data, p_pes );
402 /*****************************************************************************
404 *****************************************************************************
405 * Gather a PES packet.
406 *****************************************************************************/
407 void input_GatherPES( input_thread_t * p_input, data_packet_t * p_data,
408 es_descriptor_t * p_es,
409 boolean_t b_unit_start, boolean_t b_packet_lost )
411 #define p_pes (p_es->p_pes)
413 //intf_DbgMsg("PES-demultiplexing %p (%p)", p_ts_packet, p_pes);
415 /* If we lost data, insert a NULL data packet (philosophy : 0 is quite
416 * often an escape sequence in decoders, so that should make them wait
417 * for the next start code). */
418 if( b_packet_lost || p_es->b_discontinuity )
420 input_NullPacket( p_input, p_es );
423 if( b_unit_start && p_pes != NULL )
425 /* If the data packet contains the begining of a new PES packet, and
426 * if we were reassembling a PES packet, then the PES should be
427 * complete now, so parse its header and give it to the decoders. */
428 input_ParsePES( p_input, p_es );
431 if( !b_unit_start && p_pes == NULL )
433 /* Random access... */
434 p_input->p_plugin->pf_delete_packet( p_input->p_method_data, p_data );
440 /* If we are at the beginning of a new PES packet, we must fetch
441 * a new PES buffer to begin with the reassembly of this PES
442 * packet. This is also here that we can synchronize with the
443 * stream if we lost packets or if the decoder has just
445 if( (p_pes = p_input->p_plugin->pf_new_pes( p_input->p_method_data ) ) == NULL )
447 intf_ErrMsg("Out of memory");
448 p_input->b_error = 1;
451 p_pes->i_rate = p_input->stream.control.i_rate;
452 p_pes->p_first = p_data;
454 /* If the PES header fits in the first data packet, we can
455 * already set p_gather->i_pes_real_size. */
456 if( p_data->p_payload_end - p_data->p_payload_start
459 p_es->i_pes_real_size =
460 U16_AT(p_data->p_payload_start + 4) + 6;
464 p_es->i_pes_real_size = 0;
469 /* Update the relations between the data packets */
470 p_es->p_last->p_next = p_data;
473 p_es->p_last = p_data;
475 /* Size of the payload carried in the data packet */
476 p_pes->i_pes_size += (p_data->p_payload_end
477 - p_data->p_payload_start);
479 /* We can check if the packet is finished */
480 if( p_pes->i_pes_size == p_es->i_pes_real_size )
482 /* The packet is finished, parse it */
483 input_ParsePES( p_input, p_es );
494 /*****************************************************************************
495 * GetID: Get the ID of a stream
496 *****************************************************************************/
497 static u16 GetID( data_packet_t * p_data )
501 i_id = p_data->p_buffer[3]; /* stream_id */
504 /* stream_private_id */
505 i_id |= p_data->p_buffer[ 9 + p_data->p_buffer[8] ] << 8;
510 /*****************************************************************************
511 * DecodePSM: Decode the Program Stream Map information
512 *****************************************************************************/
513 static void DecodePSM( input_thread_t * p_input, data_packet_t * p_data )
515 stream_ps_data_t * p_demux =
516 (stream_ps_data_t *)p_input->stream.p_demux_data;
520 int i_new_es_number = 0;
522 intf_Msg("input info: Your stream contains Program Stream Map information");
523 intf_Msg("input info: Please send a mail to <massiot@via.ecp.fr>");
525 if( p_data->p_payload_start + 10 > p_data->p_payload_end )
527 intf_ErrMsg( "PSM too short : packet corrupt" );
531 if( p_demux->b_has_PSM
532 && p_demux->i_PSM_version == (p_data->p_buffer[6] & 0x1F) )
534 /* Already got that one. */
538 intf_DbgMsg( "Building PSM" );
539 p_demux->b_has_PSM = 1;
540 p_demux->i_PSM_version = p_data->p_buffer[6] & 0x1F;
542 /* Go to elementary_stream_map_length, jumping over
543 * program_stream_info. */
544 p_byte = p_data->p_payload_start + 10
545 + U16_AT(&p_data->p_payload_start[8]);
546 if( p_byte > p_data->p_payload_end )
548 intf_ErrMsg( "PSM too short : packet corrupt" );
551 /* This is the full size of the elementary_stream_map.
552 * 2 == elementary_stream_map_length
553 * Please note that CRC_32 is not included in the length. */
554 p_end = p_byte + 2 + U16_AT(p_byte);
556 if( p_end > p_data->p_payload_end )
558 intf_ErrMsg( "PSM too short : packet corrupt" );
562 vlc_mutex_lock( &p_input->stream.stream_lock );
564 /* 4 == minimum useful size of a section */
565 while( p_byte + 4 <= p_end )
567 es_descriptor_t * p_es = NULL;
568 u8 i_stream_id = p_byte[1];
569 /* FIXME: there will be a problem with private streams... (same
572 /* Look for the ES in the ES table */
573 for( i = i_new_es_number;
574 i < p_input->stream.pp_programs[0]->i_es_number;
577 if( p_input->stream.pp_programs[0]->pp_es[i]->i_stream_id
580 p_es = p_input->stream.pp_programs[0]->pp_es[i];
581 if( p_es->i_type != p_byte[0] )
583 input_DelES( p_input, p_es );
588 /* Move the ES to the beginning. */
589 p_input->stream.pp_programs[0]->pp_es[i]
590 = p_input->stream.pp_programs[0]->pp_es[ i_new_es_number ];
591 p_input->stream.pp_programs[0]->pp_es[ i_new_es_number ]
599 /* The goal is to have all the ES we have just read in the
600 * beginning of the pp_es table, and all the others at the end,
601 * so that we can close them more easily at the end. */
604 p_es = input_AddES( p_input, p_input->stream.pp_programs[0],
606 p_es->i_type = p_byte[0];
607 p_es->b_audio = ( p_es->i_type == MPEG1_AUDIO_ES
608 || p_es->i_type == MPEG2_AUDIO_ES
609 || p_es->i_type == AC3_AUDIO_ES
610 || p_es->i_type == LPCM_AUDIO_ES
613 /* input_AddES has inserted the new element at the end. */
614 p_input->stream.pp_programs[0]->pp_es[
615 p_input->stream.pp_programs[0]->i_es_number ]
616 = p_input->stream.pp_programs[0]->pp_es[ i_new_es_number ];
617 p_input->stream.pp_programs[0]->pp_es[ i_new_es_number ] = p_es;
620 p_byte += 4 + U16_AT(&p_byte[2]);
623 /* Un-select the streams that are no longer parts of the program. */
624 for( i = i_new_es_number;
625 i < p_input->stream.pp_programs[0]->i_es_number;
628 /* We remove pp_es[i_new_es_member] and not pp_es[i] because the
629 * list will be emptied starting from the end */
630 input_DelES( p_input,
631 p_input->stream.pp_programs[0]->pp_es[i_new_es_number] );
635 intf_Msg( "input info: The stream map after the PSM is now :" );
636 input_DumpStream( p_input );
639 vlc_mutex_unlock( &p_input->stream.stream_lock );
642 /*****************************************************************************
643 * input_ParsePS: read the PS header
644 *****************************************************************************/
645 es_descriptor_t * input_ParsePS( input_thread_t * p_input,
646 data_packet_t * p_data )
649 es_descriptor_t * p_es = NULL;
651 i_code = U32_AT( p_data->p_buffer );
652 if( i_code > 0x1BC ) /* ES start code */
657 /* This is a PES packet. Find out if we want it or not. */
658 i_id = GetID( p_data );
660 vlc_mutex_lock( &p_input->stream.stream_lock );
661 if( p_input->stream.pp_programs[0]->b_is_ok )
663 /* Look only at the selected ES. */
664 for( i_dummy = 0; i_dummy < p_input->stream.i_selected_es_number;
667 if( p_input->stream.pp_selected_es[i_dummy] != NULL
668 && p_input->stream.pp_selected_es[i_dummy]->i_id == i_id )
670 p_es = p_input->stream.pp_selected_es[i_dummy];
677 stream_ps_data_t * p_demux =
678 (stream_ps_data_t *)p_input->stream.pp_programs[0]->p_demux_data;
680 /* Search all ES ; if not found -> AddES */
681 p_es = input_FindES( p_input, i_id );
683 if( p_es == NULL && !p_demux->b_has_PSM )
685 p_es = input_AddES( p_input, p_input->stream.pp_programs[0],
689 p_es->i_stream_id = p_data->p_buffer[3];
691 /* Set stream type and auto-spawn. */
692 if( (i_id & 0xF0) == 0xE0 )
695 p_es->i_type = MPEG2_VIDEO_ES;
697 if( !p_input->stream.b_seekable )
698 input_SelectES( p_input, p_es );
701 else if( (i_id & 0xE0) == 0xC0 )
704 p_es->i_type = MPEG2_AUDIO_ES;
707 if( !p_input->stream.b_seekable )
708 if( main_GetIntVariable( INPUT_DVD_CHANNEL_VAR, 0 )
709 == (p_es->i_id & 0x1F) )
710 switch( main_GetIntVariable( INPUT_DVD_AUDIO_VAR, 0 ) )
713 main_PutIntVariable( INPUT_DVD_CHANNEL_VAR,
716 input_SelectES( p_input, p_es );
720 else if( (i_id & 0xF0FF) == 0x80BD )
722 /* AC3 audio (0x80->0x8F) */
723 p_es->i_type = AC3_AUDIO_ES;
726 if( !p_input->stream.b_seekable )
727 if( main_GetIntVariable( INPUT_DVD_CHANNEL_VAR, 0 )
728 == ((p_es->i_id & 0xF00) >> 8) )
729 switch( main_GetIntVariable( INPUT_DVD_AUDIO_VAR, 0 ) )
732 main_PutIntVariable( INPUT_DVD_CHANNEL_VAR,
735 input_SelectES( p_input, p_es );
739 else if( (i_id & 0xE0FF) == 0x20BD )
741 /* Subtitles video (0x20->0x3F) */
742 p_es->i_type = DVD_SPU_ES;
744 if( main_GetIntVariable( INPUT_DVD_SUBTITLE_VAR, -1 )
745 == ((p_es->i_id & 0x1F00) >> 8) )
747 if( !p_input->stream.b_seekable )
748 input_SelectES( p_input, p_es );
752 else if( (i_id & 0xF0FF) == 0xA0BD )
754 /* LPCM audio (0xA0->0xAF) */
755 p_es->i_type = LPCM_AUDIO_ES;
757 /* FIXME : write the decoder */
761 p_es->i_type = UNKNOWN_ES;
765 } /* stream.b_is_ok */
766 vlc_mutex_unlock( &p_input->stream.stream_lock );
767 } /* i_code > 0xBC */
772 /*****************************************************************************
773 * input_DemuxPS: first step of demultiplexing: the PS header
774 *****************************************************************************/
775 void input_DemuxPS( input_thread_t * p_input, data_packet_t * p_data )
778 boolean_t b_trash = 0;
779 es_descriptor_t * p_es = NULL;
781 i_code = U32_AT( p_data->p_buffer );
782 if( i_code <= 0x1BC )
786 case 0x1BA: /* PACK_START_CODE */
791 if( (p_data->p_buffer[4] & 0xC0) == 0x40 )
795 ((mtime_t)(p_data->p_buffer[4] & 0x38) << 27) |
796 ((mtime_t)(U32_AT(p_data->p_buffer + 4) & 0x03FFF800)
798 ((mtime_t)(U32_AT(p_data->p_buffer + 6) & 0x03FFF800)
803 /* MPEG-1 SCR is like PTS. */
805 ((mtime_t)(p_data->p_buffer[4] & 0x0E) << 29) |
806 (((mtime_t)U16_AT(p_data->p_buffer + 5) << 14)
808 ((mtime_t)U16_AT(p_data->p_buffer + 7) >> 1);
810 /* Call the pace control. */
811 //intf_Msg("+%lld", scr_time);
812 input_ClockManageRef( p_input, p_input->stream.pp_programs[0],
818 case 0x1BB: /* SYSTEM_START_CODE */
819 b_trash = 1; /* Nothing interesting */
822 case 0x1BC: /* PROGRAM_STREAM_MAP_CODE */
823 DecodePSM( p_input, p_data );
827 case 0x1B9: /* PROGRAM_END_CODE */
832 /* This should not happen */
834 intf_WarnMsg( 1, "Unwanted packet received with start code %x",
840 p_es = input_ParsePS( p_input, p_data );
842 vlc_mutex_lock( &p_input->stream.control.control_lock );
843 if( p_es != NULL && p_es->p_decoder_fifo != NULL
844 && (!p_es->b_audio || !p_input->stream.control.b_mute) )
846 vlc_mutex_unlock( &p_input->stream.control.control_lock );
850 input_GatherPES( p_input, p_data, p_es, 1, 0 );
854 vlc_mutex_unlock( &p_input->stream.control.control_lock );
859 /* Trash the packet if it has no payload or if it isn't selected */
862 p_input->p_plugin->pf_delete_packet( p_input->p_method_data, p_data );
864 p_input->c_packets_trashed++;
874 /*****************************************************************************
875 * input_DemuxTS: first step of demultiplexing: the TS header
876 *****************************************************************************/
877 void input_DemuxTS( input_thread_t * p_input, data_packet_t * p_data )
880 boolean_t b_adaptation; /* Adaptation field is present */
881 boolean_t b_payload; /* Packet carries payload */
882 boolean_t b_unit_start; /* A PSI or a PES start in the packet */
883 boolean_t b_trash = 0; /* Is the packet unuseful ? */
884 boolean_t b_lost = 0; /* Was there a packet loss ? */
885 es_descriptor_t * p_es = NULL;
886 es_ts_data_t * p_es_demux = NULL;
887 pgrm_ts_data_t * p_pgrm_demux = NULL;
889 #define p (p_data->p_buffer)
891 //intf_DbgMsg("input debug: TS-demultiplexing packet %p, pid %d",
892 // p_ts_packet, U16_AT(&p[1]) & 0x1fff);
894 /* Extract flags values from TS common header. */
895 i_pid = U16_AT(&p[1]) & 0x1fff;
896 b_unit_start = (p[1] & 0x40);
897 b_adaptation = (p[3] & 0x20);
898 b_payload = (p[3] & 0x10);
900 /* Find out the elementary stream. */
901 vlc_mutex_lock( &p_input->stream.stream_lock );
902 p_es = input_FindES( p_input, i_pid );
904 vlc_mutex_lock( &p_input->stream.control.control_lock );
905 if( p_es == NULL || p_es->p_decoder_fifo == NULL
906 || (p_es->b_audio && p_input->stream.control.b_mute) )
908 /* Not selected. Just read the adaptation field for a PCR. */
911 vlc_mutex_unlock( &p_input->stream.control.control_lock );
912 vlc_mutex_unlock( &p_input->stream.stream_lock );
914 if( (p_es->p_decoder_fifo != NULL) || (p_pgrm_demux->i_pcr_pid == i_pid) )
920 /* Extract adaptation field information if any */
923 /* We don't have any adaptation_field, so payload starts
924 * immediately after the 4 byte TS header */
925 p_data->p_payload_start += 4;
929 /* p[4] is adaptation_field_length minus one */
930 p_data->p_payload_start += 5 + p[4];
932 /* The adaptation field can be limited to the
933 * adaptation_field_length byte, so that there is nothing to do:
934 * skip this possibility */
937 /* If the packet has both adaptation_field and payload,
938 * adaptation_field cannot be more than 182 bytes long; if
939 * there is only an adaptation_field, it must fill the next
941 if( b_payload ? (p[4] > 182) : (p[4] != 183) )
944 "invalid TS adaptation field (%p)",
946 p_data->b_discard_payload = 1;
948 p_es->c_invalid_packets++;
952 /* Now we are sure that the byte containing flags is present:
956 /* discontinuity_indicator */
960 "discontinuity_indicator"
961 " encountered by TS demux (position read: %d,"
963 p[5] & 0x80, p_es_demux->i_continuity_counter );
965 /* If the PID carries the PCR, there will be a system
966 * time-based discontinuity. We let the PCR decoder
968 p_es->p_pgrm->b_discontinuity = 1;
970 /* There also may be a continuity_counter
971 * discontinuity: resynchronise our counter with
972 * the one of the stream. */
973 p_es_demux->i_continuity_counter = (p[3] & 0x0f) - 1;
976 /* If this is a PCR_PID, and this TS packet contains a
977 * PCR, we pass it along to the PCR decoder. */
978 if( (p_pgrm_demux->i_pcr_pid == i_pid) && (p[5] & 0x10) )
980 /* There should be a PCR field in the packet, check
981 * if the adaptation field is long enough to carry
988 ( (mtime_t)U32_AT((u32*)&p[6]) << 1 )
990 /* Call the pace control. */
991 input_ClockManageRef( p_input, p_es->p_pgrm,
995 } /* valid TS adaptation field ? */
997 } /* has adaptation field */
999 /* Check the continuity of the stream. */
1000 i_dummy = ((p[3] & 0x0f) - p_es_demux->i_continuity_counter) & 0x0f;
1003 /* Everything is ok, just increase our counter */
1004 p_es_demux->i_continuity_counter++;
1008 if( !b_payload && i_dummy == 0 )
1010 /* This is a packet without payload, this is allowed by the
1011 * draft. As there is nothing interesting in this packet
1012 * (except PCR that have already been handled), we can trash
1015 "Packet without payload received by TS demux" );
1018 else if( i_dummy <= 0 )
1020 /* FIXME: this can never happen, can it ? --Meuuh */
1021 /* Duplicate packet: mark it as being to be trashed. */
1022 intf_WarnMsg( 1, "Duplicate packet received by TS demux" );
1025 else if( p_es_demux->i_continuity_counter == 0xFF )
1027 /* This means that the packet is the first one we receive for
1028 * this ES since the continuity counter ranges between 0 and
1029 * 0x0F excepts when it has been initialized by the input:
1030 * init the counter to the correct value. */
1031 intf_DbgMsg( "First packet for PID %d received by TS demux",
1033 p_es_demux->i_continuity_counter = (p[3] & 0x0f);
1037 /* This can indicate that we missed a packet or that the
1038 * continuity_counter wrapped and we received a dup packet:
1039 * as we don't know, do as if we missed a packet to be sure
1040 * to recover from this situation */
1042 "Packet lost by TS demux: current %d, packet %d",
1043 p_es_demux->i_continuity_counter & 0x0f,
1046 p_es_demux->i_continuity_counter = p[3] & 0x0f;
1047 } /* not continuous */
1049 } /* if selected or PCR */
1051 /* Trash the packet if it has no payload or if it isn't selected */
1054 p_input->p_plugin->pf_delete_packet( p_input, p_data );
1056 p_input->c_packets_trashed++;
1061 if( p_es_demux->b_psi )
1063 /* The payload contains PSI tables */
1065 /* FIXME ! write the PSI decoder :p */
1066 input_DemuxPSI( p_input, p_data, p_es,
1067 b_unit_start, b_lost );
1072 /* The payload carries a PES stream */
1074 input_GatherPES( p_input, p_data, p_es, b_unit_start, b_lost );