1 /*****************************************************************************
2 * input_ext-dec.h: structures exported to the VideoLAN decoders
3 *****************************************************************************
4 * Copyright (C) 1999-2001 VideoLAN
5 * $Id: input_ext-dec.h,v 1.52 2002/01/21 23:57:46 massiot Exp $
7 * Authors: Christophe Massiot <massiot@via.ecp.fr>
8 * Michel Kaempf <maxx@via.ecp.fr>
10 * This program is free software; you can redistribute it and/or modify
11 * it under the terms of the GNU General Public License as published by
12 * the Free Software Foundation; either version 2 of the License, or
13 * (at your option) any later version.
15 * This program is distributed in the hope that it will be useful,
16 * but WITHOUT ANY WARRANTY; without even the implied warranty of
17 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
18 * GNU General Public License for more details.
20 * You should have received a copy of the GNU General Public License
21 * along with this program; if not, write to the Free Software
22 * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111, USA.
23 *****************************************************************************/
25 /* ES streams types - see ISO/IEC 13818-1 table 2-29 numbers */
26 #define MPEG1_VIDEO_ES 0x01
27 #define MPEG2_VIDEO_ES 0x02
28 #define MPEG1_AUDIO_ES 0x03
29 #define MPEG2_AUDIO_ES 0x04
30 #define AC3_AUDIO_ES 0x81
31 /* These ones might violate the norm : */
32 #define DVD_SPU_ES 0x82
33 #define LPCM_AUDIO_ES 0x83
34 #define UNKNOWN_ES 0xFF
36 /* Structures exported to the decoders */
38 /*****************************************************************************
40 *****************************************************************************
41 * Describe a data packet.
42 *****************************************************************************/
44 /* start of the PS or TS packet */ \
45 byte_t * p_demux_start; \
46 /* start of the PES payload in this packet */ \
47 byte_t * p_payload_start; \
48 byte_t * p_payload_end; /* guess ? :-) */ \
49 /* is the packet messed up ? */ \
50 boolean_t b_discard_payload;
52 typedef struct data_packet_s
54 /* Used to chain the packets that carry data for a same PES or PSI */
55 struct data_packet_s * p_next;
59 /* Please note that at least one buffer allocator (in particular, the
60 * Next Generation Buffer Allocator) extends this structure with
61 * private data after DATA_PACKET. */
64 /*****************************************************************************
66 *****************************************************************************
67 * Describes an PES packet, with its properties, and pointers to the TS packets
69 *****************************************************************************/
70 typedef struct pes_packet_s
72 /* Chained list to the next PES packet (depending on the context) */
73 struct pes_packet_s * p_next;
76 boolean_t b_data_alignment; /* used to find the beginning of
77 * a video or audio unit */
78 boolean_t b_discontinuity; /* This packet doesn't follow the
81 mtime_t i_pts; /* PTS for this packet (zero if unset) */
82 mtime_t i_dts; /* DTS for this packet (zero if unset) */
83 int i_rate; /* current pace of reading
84 * (see stream_control.h) */
86 unsigned int i_pes_size; /* size of the current PES packet */
88 /* Chained list to packets */
89 data_packet_t * p_first; /* The first packet contained by this
90 * PES (used by decoders). */
91 data_packet_t * p_last; /* The last packet contained by this
92 PES (used by the buffer allocator) */
93 unsigned int i_nb_data; /* Number of data packets in the chained
97 /*****************************************************************************
99 *****************************************************************************
100 * This rotative FIFO contains PES packets that are to be decoded.
101 *****************************************************************************/
102 typedef struct decoder_fifo_s
104 /* Thread structures */
105 vlc_mutex_t data_lock; /* fifo data lock */
106 vlc_cond_t data_wait; /* fifo data conditional variable */
109 pes_packet_t * p_first;
110 pes_packet_t ** pp_last;
111 int i_depth; /* number of PES packets in the stack */
113 /* Communication interface between input and decoders */
114 boolean_t b_die; /* the decoder should return now */
115 boolean_t b_error; /* the decoder is in an error loop */
116 void * p_packets_mgt; /* packets management services
117 * data (netlist...) */
118 void (* pf_delete_pes)( void *, pes_packet_t * );
119 /* function to use when releasing a PES */
122 /*****************************************************************************
123 * bit_fifo_t : bit fifo descriptor
124 *****************************************************************************
125 * This type describes a bit fifo used to store bits while working with the
126 * input stream at the bit level.
127 *****************************************************************************/
128 typedef u32 WORD_TYPE;
130 typedef struct bit_fifo_s
132 /* This unsigned integer allows us to work at the bit level. This buffer
133 * can contain 32 bits, and the used space can be found on the MSb's side
134 * and the available space on the LSb's side. */
137 /* Number of bits available in the bit buffer */
142 /*****************************************************************************
143 * bit_stream_t : bit stream descriptor
144 *****************************************************************************
145 * This type, based on a PES stream, includes all the structures needed to
146 * handle the input stream like a bit stream.
147 *****************************************************************************/
148 typedef struct bit_stream_s
158 /* The decoder fifo contains the data of the PES stream */
159 decoder_fifo_t * p_decoder_fifo;
161 /* Callback to the decoder used when changing data packets ; set
162 * to NULL if your decoder doesn't need it. */
163 void (* pf_bitstream_callback)( struct bit_stream_s *,
164 boolean_t b_new_pes );
165 /* Optional argument to the callback */
166 void * p_callback_arg;
171 mtime_t i_pts, i_dts;
172 byte_t * p_pts_validity;
177 /* Current data packet (in the current PES packet of the PES stream) */
178 data_packet_t * p_data;
179 /* Pointer to the next byte that is to be read (in the current packet) */
181 /* Pointer to the last byte that is to be read (in the current packet */
183 /* Temporary buffer in case we're not aligned when changing data packets */
184 WORD_TYPE i_showbits_buffer;
185 data_packet_t showbits_data;
188 /*****************************************************************************
189 * Inline functions used by the decoders to read bit_stream_t
190 *****************************************************************************/
193 * DISCUSSION : How to use the bit_stream structures
195 * sizeof(WORD_TYPE) (usually 32) bits are read at the same time, thus
196 * minimizing the number of p_byte changes.
197 * Bits are read via GetBits() or ShowBits.
199 * XXX : Be aware that if, in the forthcoming functions, i_bits > 24,
200 * the data have to be already aligned on an 8-bit boundary, or wrong
201 * results will be returned. Use RealignBits() if unsure.
204 #if (WORD_TYPE == u32)
205 # define WORD_AT U32_AT
206 # define WORD_SIGNED s32
207 #elif (WORD_TYPE == u64)
208 # define WORD_AT U64_AT
209 # define WORD_SIGNED s64
211 # error Unsupported WORD_TYPE
214 /*****************************************************************************
215 * Prototypes from input_ext-dec.c
216 *****************************************************************************/
218 void InitBitstream ( struct bit_stream_s *, struct decoder_fifo_s *,
219 void (* pf_bitstream_callback)( struct bit_stream_s *,
221 void * p_callback_arg );
222 boolean_t NextDataPacket( struct decoder_fifo_s *, struct data_packet_s ** );
223 void BitstreamNextDataPacket( struct bit_stream_s * );
224 u32 UnalignedShowBits( struct bit_stream_s *, unsigned int );
225 void UnalignedRemoveBits( struct bit_stream_s * );
226 u32 UnalignedGetBits( struct bit_stream_s *, unsigned int );
227 void CurrentPTS( struct bit_stream_s *, mtime_t *, mtime_t * );
229 # define InitBitstream p_symbols->InitBitstream
230 # define NextDataPacket p_symbols->NextDataPacket
231 # define BitstreamNextDataPacket p_symbols->BitstreamNextDataPacket
232 # define UnalignedShowBits p_symbols->UnalignedShowBits
233 # define UnalignedRemoveBits p_symbols->UnalignedRemoveBits
234 # define UnalignedGetBits p_symbols->UnalignedGetBits
235 # define CurrentPTS p_symbols->CurrentPTS
238 /*****************************************************************************
239 * AlignWord : fill in the bit buffer so that the byte pointer be aligned
240 * on a word boundary (XXX: there must be at least sizeof(WORD_TYPE) - 1
241 * empty bytes in the bit buffer)
242 *****************************************************************************/
243 static __inline__ void AlignWord( bit_stream_t * p_bit_stream )
245 while( (ptrdiff_t)p_bit_stream->p_byte
246 & (sizeof(WORD_TYPE) - 1) )
248 if( p_bit_stream->p_byte < p_bit_stream->p_end )
250 p_bit_stream->fifo.buffer |= *(p_bit_stream->p_byte++)
251 << (8 * sizeof(WORD_TYPE) - 8
252 - p_bit_stream->fifo.i_available);
253 p_bit_stream->fifo.i_available += 8;
257 BitstreamNextDataPacket( p_bit_stream );
258 p_bit_stream->fifo.buffer |= *(p_bit_stream->p_byte++)
259 << (8 * sizeof(WORD_TYPE) - 8
260 - p_bit_stream->fifo.i_available);
261 p_bit_stream->fifo.i_available += 8;
266 /*****************************************************************************
267 * ShowBits : return i_bits bits from the bit stream
268 *****************************************************************************/
269 static __inline__ u32 ShowBits( bit_stream_t * p_bit_stream,
270 unsigned int i_bits )
272 if( p_bit_stream->fifo.i_available >= i_bits )
274 return( p_bit_stream->fifo.buffer >> (8 * sizeof(WORD_TYPE) - i_bits) );
277 if( p_bit_stream->p_byte <= p_bit_stream->p_end - sizeof(WORD_TYPE) )
279 return( (p_bit_stream->fifo.buffer |
280 (WORD_AT( p_bit_stream->p_byte )
281 >> p_bit_stream->fifo.i_available))
282 >> (8 * sizeof(WORD_TYPE) - i_bits) );
285 return( UnalignedShowBits( p_bit_stream, i_bits ) );
288 /*****************************************************************************
289 * ShowSignedBits : return i_bits bits from the bit stream, using signed
291 *****************************************************************************/
292 static __inline__ s32 ShowSignedBits( bit_stream_t * p_bit_stream,
293 unsigned int i_bits )
295 if( p_bit_stream->fifo.i_available >= i_bits )
297 return( (WORD_SIGNED)p_bit_stream->fifo.buffer
298 >> (8 * sizeof(WORD_TYPE) - i_bits) );
301 /* You can probably do something a little faster, but now I'm tired. */
302 return( (WORD_SIGNED)(ShowBits( p_bit_stream, i_bits ) << (32 - i_bits))
306 /*****************************************************************************
307 * RemoveBits : removes i_bits bits from the bit buffer
308 * XXX: do not use for 32 bits, see RemoveBits32
309 *****************************************************************************/
310 static __inline__ void RemoveBits( bit_stream_t * p_bit_stream,
311 unsigned int i_bits )
313 p_bit_stream->fifo.i_available -= i_bits;
315 if( p_bit_stream->fifo.i_available >= 0 )
317 p_bit_stream->fifo.buffer <<= i_bits;
321 if( p_bit_stream->p_byte <= p_bit_stream->p_end - sizeof(WORD_TYPE) )
323 p_bit_stream->fifo.buffer = WORD_AT( p_bit_stream->p_byte )
324 << ( -p_bit_stream->fifo.i_available );
325 ((WORD_TYPE *)p_bit_stream->p_byte)++;
326 p_bit_stream->fifo.i_available += sizeof(WORD_TYPE) * 8;
330 UnalignedRemoveBits( p_bit_stream );
333 /*****************************************************************************
334 * RemoveBits32 : removes 32 bits from the bit buffer (and as a side effect,
336 *****************************************************************************/
337 #if (WORD_TYPE == u32)
338 static __inline__ void RemoveBits32( bit_stream_t * p_bit_stream )
340 if( p_bit_stream->p_byte <= p_bit_stream->p_end - sizeof(WORD_TYPE) )
342 if( p_bit_stream->fifo.i_available )
344 p_bit_stream->fifo.buffer = WORD_AT( p_bit_stream->p_byte )
345 << (32 - p_bit_stream->fifo.i_available);
346 ((WORD_TYPE *)p_bit_stream->p_byte)++;
350 ((WORD_TYPE *)p_bit_stream->p_byte)++;
354 p_bit_stream->fifo.i_available -= 32;
355 UnalignedRemoveBits( p_bit_stream );
358 # define RemoveBits32( p_bit_stream ) RemoveBits( p_bit_stream, 32 )
361 /*****************************************************************************
362 * GetBits : returns i_bits bits from the bit stream and removes them
363 * XXX: do not use for 32 bits, see GetBits32
364 *****************************************************************************/
365 static __inline__ u32 GetBits( bit_stream_t * p_bit_stream,
366 unsigned int i_bits )
370 p_bit_stream->fifo.i_available -= i_bits;
372 if( p_bit_stream->fifo.i_available >= 0 )
374 i_result = p_bit_stream->fifo.buffer
375 >> (8 * sizeof(WORD_TYPE) - i_bits);
376 p_bit_stream->fifo.buffer <<= i_bits;
380 if( p_bit_stream->p_byte <= p_bit_stream->p_end - sizeof(WORD_TYPE) )
382 i_result = p_bit_stream->fifo.buffer
383 >> (8 * sizeof(WORD_TYPE) - i_bits);
384 p_bit_stream->fifo.buffer = WORD_AT( p_bit_stream->p_byte );
385 ((WORD_TYPE *)p_bit_stream->p_byte)++;
386 i_result |= p_bit_stream->fifo.buffer
387 >> (8 * sizeof(WORD_TYPE)
388 + p_bit_stream->fifo.i_available);
389 p_bit_stream->fifo.buffer <<= ( -p_bit_stream->fifo.i_available );
390 p_bit_stream->fifo.i_available += sizeof(WORD_TYPE) * 8;
394 return UnalignedGetBits( p_bit_stream, i_bits );
397 /*****************************************************************************
398 * GetSignedBits : returns i_bits bits from the bit stream and removes them,
399 * using signed arithmetic
400 * XXX: do not use for 32 bits
401 *****************************************************************************/
402 static __inline__ s32 GetSignedBits( bit_stream_t * p_bit_stream,
403 unsigned int i_bits )
405 if( p_bit_stream->fifo.i_available >= i_bits )
409 p_bit_stream->fifo.i_available -= i_bits;
410 i_result = (WORD_SIGNED)p_bit_stream->fifo.buffer
411 >> (8 * sizeof(WORD_TYPE) - i_bits);
412 p_bit_stream->fifo.buffer <<= i_bits;
416 /* You can probably do something a little faster, but now I'm tired. */
417 return( (WORD_SIGNED)(GetBits( p_bit_stream, i_bits ) << (32 - i_bits))
421 /*****************************************************************************
422 * GetBits32 : returns 32 bits from the bit stream and removes them
423 *****************************************************************************/
424 #if (WORD_TYPE == u32)
425 static __inline__ u32 GetBits32( bit_stream_t * p_bit_stream )
429 if( p_bit_stream->fifo.i_available == 32 )
431 p_bit_stream->fifo.i_available = 0;
432 i_result = p_bit_stream->fifo.buffer;
433 p_bit_stream->fifo.buffer = 0;
437 if( p_bit_stream->p_byte <= p_bit_stream->p_end - sizeof(WORD_TYPE) )
439 if( p_bit_stream->fifo.i_available )
441 i_result = p_bit_stream->fifo.buffer;
442 p_bit_stream->fifo.buffer = WORD_AT( p_bit_stream->p_byte );
443 ((WORD_TYPE *)p_bit_stream->p_byte)++;
444 i_result |= p_bit_stream->fifo.buffer
445 >> (p_bit_stream->fifo.i_available);
446 p_bit_stream->fifo.buffer <<= (32 - p_bit_stream->fifo.i_available);
450 i_result = WORD_AT( p_bit_stream->p_byte );
451 ((WORD_TYPE *)p_bit_stream->p_byte)++;
455 p_bit_stream->fifo.i_available -= 32;
456 return UnalignedGetBits( p_bit_stream, 32 );
459 # define GetBits32( p_bit_stream ) GetBits( p_bit_stream, 32 )
462 /*****************************************************************************
463 * RealignBits : realigns the bit buffer on an 8-bit boundary
464 *****************************************************************************/
465 static __inline__ void RealignBits( bit_stream_t * p_bit_stream )
467 p_bit_stream->fifo.buffer <<= (p_bit_stream->fifo.i_available & 0x7);
468 p_bit_stream->fifo.i_available &= ~0x7;
472 /*****************************************************************************
473 * GetChunk : reads a large chunk of data
474 *****************************************************************************
475 * The position in the stream must be byte-aligned, if unsure call
476 * RealignBits(). p_buffer must point to a buffer at least as big as i_buf_len
477 * otherwise your code will crash.
478 *****************************************************************************/
479 static __inline__ void GetChunk( bit_stream_t * p_bit_stream,
480 byte_t * p_buffer, size_t i_buf_len )
482 ptrdiff_t i_available;
484 /* We need to take care because i_buf_len may be < 4. */
485 while( p_bit_stream->fifo.i_available > 0 && i_buf_len )
487 *p_buffer = p_bit_stream->fifo.buffer >> (8 * sizeof(WORD_TYPE) - 8);
490 p_bit_stream->fifo.buffer <<= 8;
491 p_bit_stream->fifo.i_available -= 8;
494 if( (i_available = p_bit_stream->p_end - p_bit_stream->p_byte)
497 FAST_MEMCPY( p_buffer, p_bit_stream->p_byte, i_buf_len );
498 p_bit_stream->p_byte += i_buf_len;
504 FAST_MEMCPY( p_buffer, p_bit_stream->p_byte, i_available );
505 p_bit_stream->p_byte = p_bit_stream->p_end;
506 p_buffer += i_available;
507 i_buf_len -= i_available;
508 BitstreamNextDataPacket( p_bit_stream );
510 while( (i_available = p_bit_stream->p_end - p_bit_stream->p_byte)
511 <= i_buf_len && !p_bit_stream->p_decoder_fifo->b_die );
515 FAST_MEMCPY( p_buffer, p_bit_stream->p_byte, i_buf_len );
516 p_bit_stream->p_byte += i_buf_len;
520 if( p_bit_stream->p_byte <= p_bit_stream->p_end - sizeof(WORD_TYPE) )
522 AlignWord( p_bit_stream );
528 * Communication interface between input and decoders
531 /*****************************************************************************
533 *****************************************************************************
534 * Standard pointers given to the decoders as a toolbox.
535 *****************************************************************************/
536 typedef struct decoder_config_s
539 u8 i_type; /* type of the elementary stream */
541 struct stream_ctrl_s * p_stream_ctrl;
542 struct decoder_fifo_s * p_decoder_fifo;
545 /*****************************************************************************
546 * Prototypes from input_dec.c
547 *****************************************************************************/
549 void DecoderError ( struct decoder_fifo_s * p_fifo );
551 # define DecoderError p_symbols->DecoderError