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 1.58 2002/05/18 17:47:46 sam 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 MSMPEG4v1_VIDEO_ES 0x40
35 #define MSMPEG4v2_VIDEO_ES 0x41
36 #define MSMPEG4v3_VIDEO_ES 0x42
37 #define MPEG4_VIDEO_ES 0x50
39 #define UNKNOWN_ES 0xFF
41 /* Structures exported to the decoders */
43 /*****************************************************************************
45 *****************************************************************************
46 * Describe a data packet.
47 *****************************************************************************/
48 typedef struct data_packet_s
50 /* Used to chain the packets that carry data for a same PES or PSI */
51 struct data_packet_s * p_next;
53 /* start of the PS or TS packet */
54 byte_t * p_demux_start;
55 /* start of the PES payload in this packet */
56 byte_t * p_payload_start;
57 byte_t * p_payload_end; /* guess ? :-) */
58 /* is the packet messed up ? */
59 boolean_t b_discard_payload;
61 /* pointer to the real data */
62 struct data_buffer_s * p_buffer;
65 /*****************************************************************************
67 *****************************************************************************
68 * Describes an PES packet, with its properties, and pointers to the TS packets
70 *****************************************************************************/
71 typedef struct pes_packet_s
73 /* Chained list to the next PES packet (depending on the context) */
74 struct pes_packet_s * p_next;
77 boolean_t b_data_alignment; /* used to find the beginning of
78 * a video or audio unit */
79 boolean_t b_discontinuity; /* This packet doesn't follow the
82 mtime_t i_pts; /* PTS for this packet (zero if unset) */
83 mtime_t i_dts; /* DTS for this packet (zero if unset) */
84 int i_rate; /* current pace of reading
85 * (see stream_control.h) */
87 unsigned int i_pes_size; /* size of the current PES packet */
89 /* Chained list to packets */
90 data_packet_t * p_first; /* The first packet contained by this
91 * PES (used by decoders). */
92 data_packet_t * p_last; /* The last packet contained by this
93 PES (used by the buffer allocator) */
94 unsigned int i_nb_data; /* Number of data packets in the chained
98 /*****************************************************************************
100 *****************************************************************************
101 * This rotative FIFO contains PES packets that are to be decoded.
102 *****************************************************************************/
103 typedef struct decoder_fifo_s
105 /* Thread structures */
106 vlc_mutex_t data_lock; /* fifo data lock */
107 vlc_cond_t data_wait; /* fifo data conditional variable */
110 pes_packet_t * p_first;
111 pes_packet_t ** pp_last;
112 int i_depth; /* number of PES packets in the stack */
114 /* Communication interface between input and decoders */
115 boolean_t b_die; /* the decoder should return now */
116 boolean_t b_error; /* the decoder is in an error loop */
117 struct input_buffers_s *p_packets_mgt; /* packets management services
121 /*****************************************************************************
122 * bit_fifo_t : bit fifo descriptor
123 *****************************************************************************
124 * This type describes a bit fifo used to store bits while working with the
125 * input stream at the bit level.
126 *****************************************************************************/
127 typedef u32 WORD_TYPE;
129 typedef struct bit_fifo_s
131 /* This unsigned integer allows us to work at the bit level. This buffer
132 * can contain 32 bits, and the used space can be found on the MSb's side
133 * and the available space on the LSb's side. */
136 /* Number of bits available in the bit buffer */
141 /*****************************************************************************
142 * bit_stream_t : bit stream descriptor
143 *****************************************************************************
144 * This type, based on a PES stream, includes all the structures needed to
145 * handle the input stream like a bit stream.
146 *****************************************************************************/
147 typedef struct bit_stream_s
157 /* The decoder fifo contains the data of the PES stream */
158 decoder_fifo_t * p_decoder_fifo;
160 /* Callback to the decoder used when changing data packets ; set
161 * to NULL if your decoder doesn't need it. */
162 void (* pf_bitstream_callback)( struct bit_stream_s *,
163 boolean_t b_new_pes );
164 /* Optional argument to the callback */
165 void * p_callback_arg;
170 mtime_t i_pts, i_dts;
171 byte_t * p_pts_validity;
176 /* Current data packet (in the current PES packet of the PES stream) */
177 data_packet_t * p_data;
178 /* Pointer to the next byte that is to be read (in the current packet) */
180 /* Pointer to the last byte that is to be read (in the current packet */
182 /* Temporary buffer in case we're not aligned when changing data packets */
183 WORD_TYPE i_showbits_buffer;
184 data_packet_t showbits_data;
187 /*****************************************************************************
188 * Inline functions used by the decoders to read bit_stream_t
189 *****************************************************************************/
192 * DISCUSSION : How to use the bit_stream structures
194 * sizeof(WORD_TYPE) (usually 32) bits are read at the same time, thus
195 * minimizing the number of p_byte changes.
196 * Bits are read via GetBits() or ShowBits.
198 * XXX : Be aware that if, in the forthcoming functions, i_bits > 24,
199 * the data have to be already aligned on an 8-bit boundary, or wrong
200 * results will be returned. Use RealignBits() if unsure.
203 #if (WORD_TYPE == u32)
204 # define WORD_AT U32_AT
205 # define WORD_SIGNED s32
206 #elif (WORD_TYPE == u64)
207 # define WORD_AT U64_AT
208 # define WORD_SIGNED s64
210 # error Unsupported WORD_TYPE
213 /*****************************************************************************
214 * Prototypes from input_ext-dec.c
215 *****************************************************************************/
217 void InitBitstream ( struct bit_stream_s *, struct decoder_fifo_s *,
218 void (* pf_bitstream_callback)( struct bit_stream_s *,
220 void * p_callback_arg );
221 boolean_t NextDataPacket( struct decoder_fifo_s *, struct data_packet_s ** );
222 void BitstreamNextDataPacket( struct bit_stream_s * );
223 u32 UnalignedShowBits( struct bit_stream_s *, unsigned int );
224 void UnalignedRemoveBits( struct bit_stream_s * );
225 u32 UnalignedGetBits( struct bit_stream_s *, unsigned int );
226 void CurrentPTS( struct bit_stream_s *, mtime_t *, mtime_t * );
228 # define InitBitstream p_symbols->InitBitstream
229 # define NextDataPacket p_symbols->NextDataPacket
230 # define BitstreamNextDataPacket p_symbols->BitstreamNextDataPacket
231 # define UnalignedShowBits p_symbols->UnalignedShowBits
232 # define UnalignedRemoveBits p_symbols->UnalignedRemoveBits
233 # define UnalignedGetBits p_symbols->UnalignedGetBits
234 # define CurrentPTS p_symbols->CurrentPTS
237 /*****************************************************************************
238 * AlignWord : fill in the bit buffer so that the byte pointer be aligned
239 * on a word boundary (XXX: there must be at least sizeof(WORD_TYPE) - 1
240 * empty bytes in the bit buffer)
241 *****************************************************************************/
242 static inline void AlignWord( bit_stream_t * p_bit_stream )
244 while( (ptrdiff_t)p_bit_stream->p_byte
245 & (sizeof(WORD_TYPE) - 1) )
247 if( p_bit_stream->p_byte < p_bit_stream->p_end )
249 p_bit_stream->fifo.buffer |= *(p_bit_stream->p_byte++)
250 << (8 * sizeof(WORD_TYPE) - 8
251 - p_bit_stream->fifo.i_available);
252 p_bit_stream->fifo.i_available += 8;
256 BitstreamNextDataPacket( p_bit_stream );
257 p_bit_stream->fifo.buffer |= *(p_bit_stream->p_byte++)
258 << (8 * sizeof(WORD_TYPE) - 8
259 - p_bit_stream->fifo.i_available);
260 p_bit_stream->fifo.i_available += 8;
265 /*****************************************************************************
266 * ShowBits : return i_bits bits from the bit stream
267 *****************************************************************************/
268 static inline u32 ShowBits( bit_stream_t * p_bit_stream,
269 unsigned int i_bits )
271 if( p_bit_stream->fifo.i_available >= i_bits )
273 return( p_bit_stream->fifo.buffer >> (8 * sizeof(WORD_TYPE) - i_bits) );
276 if( p_bit_stream->p_byte <= p_bit_stream->p_end - sizeof(WORD_TYPE) )
278 return( (p_bit_stream->fifo.buffer |
279 (WORD_AT( p_bit_stream->p_byte )
280 >> p_bit_stream->fifo.i_available))
281 >> (8 * sizeof(WORD_TYPE) - i_bits) );
284 return( UnalignedShowBits( p_bit_stream, i_bits ) );
287 /*****************************************************************************
288 * ShowSignedBits : return i_bits bits from the bit stream, using signed
290 *****************************************************************************/
291 static inline s32 ShowSignedBits( bit_stream_t * p_bit_stream,
292 unsigned int i_bits )
294 if( p_bit_stream->fifo.i_available >= i_bits )
296 return( (WORD_SIGNED)p_bit_stream->fifo.buffer
297 >> (8 * sizeof(WORD_TYPE) - i_bits) );
300 /* You can probably do something a little faster, but now I'm tired. */
301 return( (WORD_SIGNED)(ShowBits( p_bit_stream, i_bits ) << (32 - i_bits))
305 /*****************************************************************************
306 * RemoveBits : removes i_bits bits from the bit buffer
307 * XXX: do not use for 32 bits, see RemoveBits32
308 *****************************************************************************/
309 static inline void RemoveBits( bit_stream_t * p_bit_stream,
310 unsigned int i_bits )
312 p_bit_stream->fifo.i_available -= i_bits;
314 if( p_bit_stream->fifo.i_available >= 0 )
316 p_bit_stream->fifo.buffer <<= i_bits;
320 if( p_bit_stream->p_byte <= p_bit_stream->p_end - sizeof(WORD_TYPE) )
322 p_bit_stream->fifo.buffer = WORD_AT( p_bit_stream->p_byte )
323 << ( -p_bit_stream->fifo.i_available );
324 ((WORD_TYPE *)p_bit_stream->p_byte)++;
325 p_bit_stream->fifo.i_available += sizeof(WORD_TYPE) * 8;
329 UnalignedRemoveBits( p_bit_stream );
332 /*****************************************************************************
333 * RemoveBits32 : removes 32 bits from the bit buffer (and as a side effect,
335 *****************************************************************************/
336 #if (WORD_TYPE == u32)
337 static inline void RemoveBits32( bit_stream_t * p_bit_stream )
339 if( p_bit_stream->p_byte <= p_bit_stream->p_end - sizeof(WORD_TYPE) )
341 if( p_bit_stream->fifo.i_available )
343 p_bit_stream->fifo.buffer = WORD_AT( p_bit_stream->p_byte )
344 << (32 - p_bit_stream->fifo.i_available);
345 ((WORD_TYPE *)p_bit_stream->p_byte)++;
349 ((WORD_TYPE *)p_bit_stream->p_byte)++;
353 p_bit_stream->fifo.i_available -= 32;
354 UnalignedRemoveBits( p_bit_stream );
357 # define RemoveBits32( p_bit_stream ) RemoveBits( p_bit_stream, 32 )
360 /*****************************************************************************
361 * GetBits : returns i_bits bits from the bit stream and removes them
362 * XXX: do not use for 32 bits, see GetBits32
363 *****************************************************************************/
364 static inline u32 GetBits( bit_stream_t * p_bit_stream,
365 unsigned int i_bits )
369 p_bit_stream->fifo.i_available -= i_bits;
371 if( p_bit_stream->fifo.i_available >= 0 )
373 i_result = p_bit_stream->fifo.buffer
374 >> (8 * sizeof(WORD_TYPE) - i_bits);
375 p_bit_stream->fifo.buffer <<= i_bits;
379 if( p_bit_stream->p_byte <= p_bit_stream->p_end - sizeof(WORD_TYPE) )
381 i_result = p_bit_stream->fifo.buffer
382 >> (8 * sizeof(WORD_TYPE) - i_bits);
383 p_bit_stream->fifo.buffer = WORD_AT( p_bit_stream->p_byte );
384 ((WORD_TYPE *)p_bit_stream->p_byte)++;
385 i_result |= p_bit_stream->fifo.buffer
386 >> (8 * sizeof(WORD_TYPE)
387 + p_bit_stream->fifo.i_available);
388 p_bit_stream->fifo.buffer <<= ( -p_bit_stream->fifo.i_available );
389 p_bit_stream->fifo.i_available += sizeof(WORD_TYPE) * 8;
393 return UnalignedGetBits( p_bit_stream, i_bits );
396 /*****************************************************************************
397 * GetSignedBits : returns i_bits bits from the bit stream and removes them,
398 * using signed arithmetic
399 * XXX: do not use for 32 bits
400 *****************************************************************************/
401 static inline s32 GetSignedBits( bit_stream_t * p_bit_stream,
402 unsigned int i_bits )
404 if( p_bit_stream->fifo.i_available >= i_bits )
408 p_bit_stream->fifo.i_available -= i_bits;
409 i_result = (WORD_SIGNED)p_bit_stream->fifo.buffer
410 >> (8 * sizeof(WORD_TYPE) - i_bits);
411 p_bit_stream->fifo.buffer <<= i_bits;
415 /* You can probably do something a little faster, but now I'm tired. */
416 return( (WORD_SIGNED)(GetBits( p_bit_stream, i_bits ) << (32 - i_bits))
420 /*****************************************************************************
421 * GetBits32 : returns 32 bits from the bit stream and removes them
422 *****************************************************************************/
423 #if (WORD_TYPE == u32)
424 static inline u32 GetBits32( bit_stream_t * p_bit_stream )
428 if( p_bit_stream->fifo.i_available == 32 )
430 p_bit_stream->fifo.i_available = 0;
431 i_result = p_bit_stream->fifo.buffer;
432 p_bit_stream->fifo.buffer = 0;
436 if( p_bit_stream->p_byte <= p_bit_stream->p_end - sizeof(WORD_TYPE) )
438 if( p_bit_stream->fifo.i_available )
440 i_result = p_bit_stream->fifo.buffer;
441 p_bit_stream->fifo.buffer = WORD_AT( p_bit_stream->p_byte );
442 ((WORD_TYPE *)p_bit_stream->p_byte)++;
443 i_result |= p_bit_stream->fifo.buffer
444 >> (p_bit_stream->fifo.i_available);
445 p_bit_stream->fifo.buffer <<= (32 - p_bit_stream->fifo.i_available);
449 i_result = WORD_AT( p_bit_stream->p_byte );
450 ((WORD_TYPE *)p_bit_stream->p_byte)++;
454 p_bit_stream->fifo.i_available -= 32;
455 return UnalignedGetBits( p_bit_stream, 32 );
458 # define GetBits32( p_bit_stream ) GetBits( p_bit_stream, 32 )
461 /*****************************************************************************
462 * RealignBits : realigns the bit buffer on an 8-bit boundary
463 *****************************************************************************/
464 static inline void RealignBits( bit_stream_t * p_bit_stream )
466 p_bit_stream->fifo.buffer <<= (p_bit_stream->fifo.i_available & 0x7);
467 p_bit_stream->fifo.i_available &= ~0x7;
471 /*****************************************************************************
472 * GetChunk : reads a large chunk of data
473 *****************************************************************************
474 * The position in the stream must be byte-aligned, if unsure call
475 * RealignBits(). p_buffer must point to a buffer at least as big as i_buf_len
476 * otherwise your code will crash.
477 *****************************************************************************/
478 static inline void GetChunk( bit_stream_t * p_bit_stream,
479 byte_t * p_buffer, size_t i_buf_len )
481 ptrdiff_t i_available;
483 /* We need to take care because i_buf_len may be < 4. */
484 while( p_bit_stream->fifo.i_available > 0 && i_buf_len )
486 *p_buffer = p_bit_stream->fifo.buffer >> (8 * sizeof(WORD_TYPE) - 8);
489 p_bit_stream->fifo.buffer <<= 8;
490 p_bit_stream->fifo.i_available -= 8;
493 if( (i_available = p_bit_stream->p_end - p_bit_stream->p_byte)
496 FAST_MEMCPY( p_buffer, p_bit_stream->p_byte, i_buf_len );
497 p_bit_stream->p_byte += i_buf_len;
503 FAST_MEMCPY( p_buffer, p_bit_stream->p_byte, i_available );
504 p_bit_stream->p_byte = p_bit_stream->p_end;
505 p_buffer += i_available;
506 i_buf_len -= i_available;
507 BitstreamNextDataPacket( p_bit_stream );
509 while( (i_available = p_bit_stream->p_end - p_bit_stream->p_byte)
510 <= i_buf_len && !p_bit_stream->p_decoder_fifo->b_die );
514 FAST_MEMCPY( p_buffer, p_bit_stream->p_byte, i_buf_len );
515 p_bit_stream->p_byte += i_buf_len;
519 if( p_bit_stream->p_byte <= p_bit_stream->p_end - sizeof(WORD_TYPE) )
521 AlignWord( p_bit_stream );
527 * Communication interface between input and decoders
530 /*****************************************************************************
532 *****************************************************************************
533 * Standard pointers given to the decoders as a toolbox.
534 *****************************************************************************/
535 typedef struct decoder_config_s
538 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