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 1.55 2002/04/23 23:44:36 fenrir 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 MSMPEG4_VIDEO_ES 0x90
35 #define MPEG4_VIDEO_ES 0x91
36 #define UNKNOWN_ES 0xFF
38 /* Structures exported to the decoders */
40 /*****************************************************************************
42 *****************************************************************************
43 * Describe a data packet.
44 *****************************************************************************/
45 typedef struct data_packet_s
47 /* Used to chain the packets that carry data for a same PES or PSI */
48 struct data_packet_s * p_next;
50 /* start of the PS or TS packet */
51 byte_t * p_demux_start;
52 /* start of the PES payload in this packet */
53 byte_t * p_payload_start;
54 byte_t * p_payload_end; /* guess ? :-) */
55 /* is the packet messed up ? */
56 boolean_t b_discard_payload;
58 /* pointer to the real data */
59 struct data_buffer_s * p_buffer;
62 /*****************************************************************************
64 *****************************************************************************
65 * Describes an PES packet, with its properties, and pointers to the TS packets
67 *****************************************************************************/
68 typedef struct pes_packet_s
70 /* Chained list to the next PES packet (depending on the context) */
71 struct pes_packet_s * p_next;
74 boolean_t b_data_alignment; /* used to find the beginning of
75 * a video or audio unit */
76 boolean_t b_discontinuity; /* This packet doesn't follow the
79 mtime_t i_pts; /* PTS for this packet (zero if unset) */
80 mtime_t i_dts; /* DTS for this packet (zero if unset) */
81 int i_rate; /* current pace of reading
82 * (see stream_control.h) */
84 unsigned int i_pes_size; /* size of the current PES packet */
86 /* Chained list to packets */
87 data_packet_t * p_first; /* The first packet contained by this
88 * PES (used by decoders). */
89 data_packet_t * p_last; /* The last packet contained by this
90 PES (used by the buffer allocator) */
91 unsigned int i_nb_data; /* Number of data packets in the chained
95 /*****************************************************************************
97 *****************************************************************************
98 * This rotative FIFO contains PES packets that are to be decoded.
99 *****************************************************************************/
100 typedef struct decoder_fifo_s
102 /* Thread structures */
103 vlc_mutex_t data_lock; /* fifo data lock */
104 vlc_cond_t data_wait; /* fifo data conditional variable */
107 pes_packet_t * p_first;
108 pes_packet_t ** pp_last;
109 int i_depth; /* number of PES packets in the stack */
111 /* Communication interface between input and decoders */
112 boolean_t b_die; /* the decoder should return now */
113 boolean_t b_error; /* the decoder is in an error loop */
114 struct input_buffers_s *p_packets_mgt; /* packets management services
118 /*****************************************************************************
119 * bit_fifo_t : bit fifo descriptor
120 *****************************************************************************
121 * This type describes a bit fifo used to store bits while working with the
122 * input stream at the bit level.
123 *****************************************************************************/
124 typedef u32 WORD_TYPE;
126 typedef struct bit_fifo_s
128 /* This unsigned integer allows us to work at the bit level. This buffer
129 * can contain 32 bits, and the used space can be found on the MSb's side
130 * and the available space on the LSb's side. */
133 /* Number of bits available in the bit buffer */
138 /*****************************************************************************
139 * bit_stream_t : bit stream descriptor
140 *****************************************************************************
141 * This type, based on a PES stream, includes all the structures needed to
142 * handle the input stream like a bit stream.
143 *****************************************************************************/
144 typedef struct bit_stream_s
154 /* The decoder fifo contains the data of the PES stream */
155 decoder_fifo_t * p_decoder_fifo;
157 /* Callback to the decoder used when changing data packets ; set
158 * to NULL if your decoder doesn't need it. */
159 void (* pf_bitstream_callback)( struct bit_stream_s *,
160 boolean_t b_new_pes );
161 /* Optional argument to the callback */
162 void * p_callback_arg;
167 mtime_t i_pts, i_dts;
168 byte_t * p_pts_validity;
173 /* Current data packet (in the current PES packet of the PES stream) */
174 data_packet_t * p_data;
175 /* Pointer to the next byte that is to be read (in the current packet) */
177 /* Pointer to the last byte that is to be read (in the current packet */
179 /* Temporary buffer in case we're not aligned when changing data packets */
180 WORD_TYPE i_showbits_buffer;
181 data_packet_t showbits_data;
184 /*****************************************************************************
185 * Inline functions used by the decoders to read bit_stream_t
186 *****************************************************************************/
189 * DISCUSSION : How to use the bit_stream structures
191 * sizeof(WORD_TYPE) (usually 32) bits are read at the same time, thus
192 * minimizing the number of p_byte changes.
193 * Bits are read via GetBits() or ShowBits.
195 * XXX : Be aware that if, in the forthcoming functions, i_bits > 24,
196 * the data have to be already aligned on an 8-bit boundary, or wrong
197 * results will be returned. Use RealignBits() if unsure.
200 #if (WORD_TYPE == u32)
201 # define WORD_AT U32_AT
202 # define WORD_SIGNED s32
203 #elif (WORD_TYPE == u64)
204 # define WORD_AT U64_AT
205 # define WORD_SIGNED s64
207 # error Unsupported WORD_TYPE
210 /*****************************************************************************
211 * Prototypes from input_ext-dec.c
212 *****************************************************************************/
214 void InitBitstream ( struct bit_stream_s *, struct decoder_fifo_s *,
215 void (* pf_bitstream_callback)( struct bit_stream_s *,
217 void * p_callback_arg );
218 boolean_t NextDataPacket( struct decoder_fifo_s *, struct data_packet_s ** );
219 void BitstreamNextDataPacket( struct bit_stream_s * );
220 u32 UnalignedShowBits( struct bit_stream_s *, unsigned int );
221 void UnalignedRemoveBits( struct bit_stream_s * );
222 u32 UnalignedGetBits( struct bit_stream_s *, unsigned int );
223 void CurrentPTS( struct bit_stream_s *, mtime_t *, mtime_t * );
225 # define InitBitstream p_symbols->InitBitstream
226 # define NextDataPacket p_symbols->NextDataPacket
227 # define BitstreamNextDataPacket p_symbols->BitstreamNextDataPacket
228 # define UnalignedShowBits p_symbols->UnalignedShowBits
229 # define UnalignedRemoveBits p_symbols->UnalignedRemoveBits
230 # define UnalignedGetBits p_symbols->UnalignedGetBits
231 # define CurrentPTS p_symbols->CurrentPTS
234 /*****************************************************************************
235 * AlignWord : fill in the bit buffer so that the byte pointer be aligned
236 * on a word boundary (XXX: there must be at least sizeof(WORD_TYPE) - 1
237 * empty bytes in the bit buffer)
238 *****************************************************************************/
239 static __inline__ void AlignWord( bit_stream_t * p_bit_stream )
241 while( (ptrdiff_t)p_bit_stream->p_byte
242 & (sizeof(WORD_TYPE) - 1) )
244 if( p_bit_stream->p_byte < p_bit_stream->p_end )
246 p_bit_stream->fifo.buffer |= *(p_bit_stream->p_byte++)
247 << (8 * sizeof(WORD_TYPE) - 8
248 - p_bit_stream->fifo.i_available);
249 p_bit_stream->fifo.i_available += 8;
253 BitstreamNextDataPacket( p_bit_stream );
254 p_bit_stream->fifo.buffer |= *(p_bit_stream->p_byte++)
255 << (8 * sizeof(WORD_TYPE) - 8
256 - p_bit_stream->fifo.i_available);
257 p_bit_stream->fifo.i_available += 8;
262 /*****************************************************************************
263 * ShowBits : return i_bits bits from the bit stream
264 *****************************************************************************/
265 static __inline__ u32 ShowBits( bit_stream_t * p_bit_stream,
266 unsigned int i_bits )
268 if( p_bit_stream->fifo.i_available >= i_bits )
270 return( p_bit_stream->fifo.buffer >> (8 * sizeof(WORD_TYPE) - i_bits) );
273 if( p_bit_stream->p_byte <= p_bit_stream->p_end - sizeof(WORD_TYPE) )
275 return( (p_bit_stream->fifo.buffer |
276 (WORD_AT( p_bit_stream->p_byte )
277 >> p_bit_stream->fifo.i_available))
278 >> (8 * sizeof(WORD_TYPE) - i_bits) );
281 return( UnalignedShowBits( p_bit_stream, i_bits ) );
284 /*****************************************************************************
285 * ShowSignedBits : return i_bits bits from the bit stream, using signed
287 *****************************************************************************/
288 static __inline__ s32 ShowSignedBits( bit_stream_t * p_bit_stream,
289 unsigned int i_bits )
291 if( p_bit_stream->fifo.i_available >= i_bits )
293 return( (WORD_SIGNED)p_bit_stream->fifo.buffer
294 >> (8 * sizeof(WORD_TYPE) - i_bits) );
297 /* You can probably do something a little faster, but now I'm tired. */
298 return( (WORD_SIGNED)(ShowBits( p_bit_stream, i_bits ) << (32 - i_bits))
302 /*****************************************************************************
303 * RemoveBits : removes i_bits bits from the bit buffer
304 * XXX: do not use for 32 bits, see RemoveBits32
305 *****************************************************************************/
306 static __inline__ void RemoveBits( bit_stream_t * p_bit_stream,
307 unsigned int i_bits )
309 p_bit_stream->fifo.i_available -= i_bits;
311 if( p_bit_stream->fifo.i_available >= 0 )
313 p_bit_stream->fifo.buffer <<= i_bits;
317 if( p_bit_stream->p_byte <= p_bit_stream->p_end - sizeof(WORD_TYPE) )
319 p_bit_stream->fifo.buffer = WORD_AT( p_bit_stream->p_byte )
320 << ( -p_bit_stream->fifo.i_available );
321 ((WORD_TYPE *)p_bit_stream->p_byte)++;
322 p_bit_stream->fifo.i_available += sizeof(WORD_TYPE) * 8;
326 UnalignedRemoveBits( p_bit_stream );
329 /*****************************************************************************
330 * RemoveBits32 : removes 32 bits from the bit buffer (and as a side effect,
332 *****************************************************************************/
333 #if (WORD_TYPE == u32)
334 static __inline__ void RemoveBits32( bit_stream_t * p_bit_stream )
336 if( p_bit_stream->p_byte <= p_bit_stream->p_end - sizeof(WORD_TYPE) )
338 if( p_bit_stream->fifo.i_available )
340 p_bit_stream->fifo.buffer = WORD_AT( p_bit_stream->p_byte )
341 << (32 - p_bit_stream->fifo.i_available);
342 ((WORD_TYPE *)p_bit_stream->p_byte)++;
346 ((WORD_TYPE *)p_bit_stream->p_byte)++;
350 p_bit_stream->fifo.i_available -= 32;
351 UnalignedRemoveBits( p_bit_stream );
354 # define RemoveBits32( p_bit_stream ) RemoveBits( p_bit_stream, 32 )
357 /*****************************************************************************
358 * GetBits : returns i_bits bits from the bit stream and removes them
359 * XXX: do not use for 32 bits, see GetBits32
360 *****************************************************************************/
361 static __inline__ u32 GetBits( bit_stream_t * p_bit_stream,
362 unsigned int i_bits )
366 p_bit_stream->fifo.i_available -= i_bits;
368 if( p_bit_stream->fifo.i_available >= 0 )
370 i_result = p_bit_stream->fifo.buffer
371 >> (8 * sizeof(WORD_TYPE) - i_bits);
372 p_bit_stream->fifo.buffer <<= i_bits;
376 if( p_bit_stream->p_byte <= p_bit_stream->p_end - sizeof(WORD_TYPE) )
378 i_result = p_bit_stream->fifo.buffer
379 >> (8 * sizeof(WORD_TYPE) - i_bits);
380 p_bit_stream->fifo.buffer = WORD_AT( p_bit_stream->p_byte );
381 ((WORD_TYPE *)p_bit_stream->p_byte)++;
382 i_result |= p_bit_stream->fifo.buffer
383 >> (8 * sizeof(WORD_TYPE)
384 + p_bit_stream->fifo.i_available);
385 p_bit_stream->fifo.buffer <<= ( -p_bit_stream->fifo.i_available );
386 p_bit_stream->fifo.i_available += sizeof(WORD_TYPE) * 8;
390 return UnalignedGetBits( p_bit_stream, i_bits );
393 /*****************************************************************************
394 * GetSignedBits : returns i_bits bits from the bit stream and removes them,
395 * using signed arithmetic
396 * XXX: do not use for 32 bits
397 *****************************************************************************/
398 static __inline__ s32 GetSignedBits( bit_stream_t * p_bit_stream,
399 unsigned int i_bits )
401 if( p_bit_stream->fifo.i_available >= i_bits )
405 p_bit_stream->fifo.i_available -= i_bits;
406 i_result = (WORD_SIGNED)p_bit_stream->fifo.buffer
407 >> (8 * sizeof(WORD_TYPE) - i_bits);
408 p_bit_stream->fifo.buffer <<= i_bits;
412 /* You can probably do something a little faster, but now I'm tired. */
413 return( (WORD_SIGNED)(GetBits( p_bit_stream, i_bits ) << (32 - i_bits))
417 /*****************************************************************************
418 * GetBits32 : returns 32 bits from the bit stream and removes them
419 *****************************************************************************/
420 #if (WORD_TYPE == u32)
421 static __inline__ u32 GetBits32( bit_stream_t * p_bit_stream )
425 if( p_bit_stream->fifo.i_available == 32 )
427 p_bit_stream->fifo.i_available = 0;
428 i_result = p_bit_stream->fifo.buffer;
429 p_bit_stream->fifo.buffer = 0;
433 if( p_bit_stream->p_byte <= p_bit_stream->p_end - sizeof(WORD_TYPE) )
435 if( p_bit_stream->fifo.i_available )
437 i_result = p_bit_stream->fifo.buffer;
438 p_bit_stream->fifo.buffer = WORD_AT( p_bit_stream->p_byte );
439 ((WORD_TYPE *)p_bit_stream->p_byte)++;
440 i_result |= p_bit_stream->fifo.buffer
441 >> (p_bit_stream->fifo.i_available);
442 p_bit_stream->fifo.buffer <<= (32 - p_bit_stream->fifo.i_available);
446 i_result = WORD_AT( p_bit_stream->p_byte );
447 ((WORD_TYPE *)p_bit_stream->p_byte)++;
451 p_bit_stream->fifo.i_available -= 32;
452 return UnalignedGetBits( p_bit_stream, 32 );
455 # define GetBits32( p_bit_stream ) GetBits( p_bit_stream, 32 )
458 /*****************************************************************************
459 * RealignBits : realigns the bit buffer on an 8-bit boundary
460 *****************************************************************************/
461 static __inline__ void RealignBits( bit_stream_t * p_bit_stream )
463 p_bit_stream->fifo.buffer <<= (p_bit_stream->fifo.i_available & 0x7);
464 p_bit_stream->fifo.i_available &= ~0x7;
468 /*****************************************************************************
469 * GetChunk : reads a large chunk of data
470 *****************************************************************************
471 * The position in the stream must be byte-aligned, if unsure call
472 * RealignBits(). p_buffer must point to a buffer at least as big as i_buf_len
473 * otherwise your code will crash.
474 *****************************************************************************/
475 static __inline__ void GetChunk( bit_stream_t * p_bit_stream,
476 byte_t * p_buffer, size_t i_buf_len )
478 ptrdiff_t i_available;
480 /* We need to take care because i_buf_len may be < 4. */
481 while( p_bit_stream->fifo.i_available > 0 && i_buf_len )
483 *p_buffer = p_bit_stream->fifo.buffer >> (8 * sizeof(WORD_TYPE) - 8);
486 p_bit_stream->fifo.buffer <<= 8;
487 p_bit_stream->fifo.i_available -= 8;
490 if( (i_available = p_bit_stream->p_end - p_bit_stream->p_byte)
493 FAST_MEMCPY( p_buffer, p_bit_stream->p_byte, i_buf_len );
494 p_bit_stream->p_byte += i_buf_len;
500 FAST_MEMCPY( p_buffer, p_bit_stream->p_byte, i_available );
501 p_bit_stream->p_byte = p_bit_stream->p_end;
502 p_buffer += i_available;
503 i_buf_len -= i_available;
504 BitstreamNextDataPacket( p_bit_stream );
506 while( (i_available = p_bit_stream->p_end - p_bit_stream->p_byte)
507 <= i_buf_len && !p_bit_stream->p_decoder_fifo->b_die );
511 FAST_MEMCPY( p_buffer, p_bit_stream->p_byte, i_buf_len );
512 p_bit_stream->p_byte += i_buf_len;
516 if( p_bit_stream->p_byte <= p_bit_stream->p_end - sizeof(WORD_TYPE) )
518 AlignWord( p_bit_stream );
524 * Communication interface between input and decoders
527 /*****************************************************************************
529 *****************************************************************************
530 * Standard pointers given to the decoders as a toolbox.
531 *****************************************************************************/
532 typedef struct decoder_config_s
535 u8 i_type; /* type of the elementary stream */
538 struct stream_ctrl_s * p_stream_ctrl;
539 struct decoder_fifo_s * p_decoder_fifo;
542 /*****************************************************************************
543 * Prototypes from input_dec.c
544 *****************************************************************************/
546 void DecoderError ( struct decoder_fifo_s * p_fifo );
548 # define DecoderError p_symbols->DecoderError