1 /*****************************************************************************
2 * input_ext-dec.h: structures exported to the VideoLAN decoders
3 *****************************************************************************
4 * Copyright (C) 1999, 2000 VideoLAN
5 * $Id: input_ext-dec.h,v 1.12 2001/01/12 11:36:49 massiot 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 /* Structures exported to the decoders */
26 /*****************************************************************************
28 *****************************************************************************
29 * Describe a data packet.
30 *****************************************************************************/
31 typedef struct data_packet_s
33 /* Nothing before this line, the code relies on that */
34 byte_t * p_buffer; /* raw data packet */
36 /* Decoders information */
37 byte_t * p_payload_start;
38 /* start of the PES payload in this packet */
39 byte_t * p_payload_end; /* guess ? :-) */
40 boolean_t b_discard_payload; /* is the packet messed up ? */
42 /* Used to chain the TS packets that carry data for a same PES or PSI */
43 struct data_packet_s * p_next;
46 /*****************************************************************************
48 *****************************************************************************
49 * Describes an PES packet, with its properties, and pointers to the TS packets
51 *****************************************************************************/
52 typedef struct pes_packet_s
55 boolean_t b_messed_up; /* At least one of the data packets
56 * has a questionable content */
57 boolean_t b_data_alignment; /* used to find the beginning of
58 * a video or audio unit */
59 boolean_t b_discontinuity; /* This packet doesn't follow the
62 mtime_t i_pts;/* the PTS for this packet (zero if unset) */
63 mtime_t i_dts;/* the DTS for this packet (zero if unset) */
65 int i_pes_size; /* size of the current PES packet */
67 /* Pointers to packets (packets are then linked by the p_prev and
68 p_next fields of the data_packet_t struct) */
69 data_packet_t * p_first; /* The first packet containing this
70 * PES (used by decoders). */
73 /*****************************************************************************
75 *****************************************************************************
76 * This rotative FIFO contains PES packets that are to be decoded.
77 *****************************************************************************/
78 typedef struct decoder_fifo_s
80 /* Thread structures */
81 vlc_mutex_t data_lock; /* fifo data lock */
82 vlc_cond_t data_wait; /* fifo data conditional variable */
85 pes_packet_t * buffer[FIFO_SIZE + 1];
89 /* Communication interface between input and decoders */
90 boolean_t b_die; /* the decoder should return now */
91 boolean_t b_error; /* the decoder is in an error loop */
92 void * p_packets_mgt; /* packets management services
93 * data (netlist...) */
94 void (* pf_delete_pes)( void *, pes_packet_t * );
95 /* function to use when releasing a PES */
98 /* Macros to manage a decoder_fifo_t structure. Please remember to take
99 * data_lock before using them. */
100 #define DECODER_FIFO_ISEMPTY( fifo ) ( (fifo).i_start == (fifo).i_end )
101 #define DECODER_FIFO_ISFULL( fifo ) ( ( ((fifo).i_end + 1 - (fifo).i_start)\
103 #define DECODER_FIFO_START( fifo ) ( (fifo).buffer[ (fifo).i_start ] )
104 #define DECODER_FIFO_INCSTART( fifo ) ( (fifo).i_start = ((fifo).i_start + 1)\
106 #define DECODER_FIFO_END( fifo ) ( (fifo).buffer[ (fifo).i_end ] )
107 #define DECODER_FIFO_INCEND( fifo ) ( (fifo).i_end = ((fifo).i_end + 1) \
110 /*****************************************************************************
111 * bit_fifo_t : bit fifo descriptor
112 *****************************************************************************
113 * This type describes a bit fifo used to store bits while working with the
114 * input stream at the bit level.
115 *****************************************************************************/
116 typedef u32 WORD_TYPE; /* only u32 is supported at the moment */
118 typedef struct bit_fifo_s
120 /* This unsigned integer allows us to work at the bit level. This buffer
121 * can contain 32 bits, and the used space can be found on the MSb's side
122 * and the available space on the LSb's side. */
125 /* Number of bits available in the bit buffer */
130 /*****************************************************************************
131 * bit_stream_t : bit stream descriptor
132 *****************************************************************************
133 * This type, based on a PES stream, includes all the structures needed to
134 * handle the input stream like a bit stream.
135 *****************************************************************************/
136 typedef struct bit_stream_s
141 /* The decoder fifo contains the data of the PES stream */
142 decoder_fifo_t * p_decoder_fifo;
144 /* Function to jump to the next data packet */
145 void (* pf_next_data_packet)( struct bit_stream_s * );
147 /* Callback to the decoder used when changing data packets ; set
148 * to NULL if your decoder doesn't need it. */
149 void (* pf_bitstream_callback)( struct bit_stream_s *,
150 boolean_t b_new_pes );
151 /* Optional argument to the callback */
152 void * p_callback_arg;
157 /* Current data packet (in the current PES packet of the PES stream) */
158 data_packet_t * p_data;
159 /* Pointer to the next byte that is to be read (in the current TS packet) */
161 /* Pointer to the last byte that is to be read (in the current TS packet */
170 /*****************************************************************************
171 * Inline functions used by the decoders to read bit_stream_t
172 *****************************************************************************/
175 * Philosophy of the first implementation : the bit buffer is first filled by
176 * NeedBits, then the buffer can be read via p_bit_stream->fifo.buffer, and
177 * unnecessary bits are dumped with a DumpBits() call.
180 /*****************************************************************************
181 * GetByte : reads the next byte in the input stream
182 *****************************************************************************/
183 static __inline__ byte_t GetByte( bit_stream_t * p_bit_stream )
185 /* Are there some bytes left in the current data packet ? */
186 /* could change this test to have a if (! (bytes--)) instead */
187 if ( p_bit_stream->p_byte >= p_bit_stream->p_end )
189 /* no, switch to next data packet */
190 p_bit_stream->pf_next_data_packet( p_bit_stream );
193 return( *(p_bit_stream->p_byte++) );
196 /*****************************************************************************
197 * NeedBits : reads i_bits new bits in the bit stream and stores them in the
199 *****************************************************************************
200 * - i_bits must be less or equal 32 !
201 * - There is something important to notice with that function : if the number
202 * of bits available in the bit buffer when calling NeedBits() is greater than
203 * 24 (i_available > 24) but less than the number of needed bits
204 * (i_available < i_bits), the byte returned by GetByte() will be shifted with
205 * a negative value and the number of bits available in the bit buffer will be
206 * set to more than 32 !
207 *****************************************************************************/
208 static __inline__ void NeedBits( bit_stream_t * p_bit_stream, int i_bits )
210 while ( p_bit_stream->fifo.i_available < i_bits )
212 p_bit_stream->fifo.buffer |= ((WORD_TYPE)GetByte( p_bit_stream ))
213 << (sizeof(WORD_TYPE) - 8
214 - p_bit_stream->fifo.i_available);
215 p_bit_stream->fifo.i_available += 8;
219 /*****************************************************************************
220 * DumpBits : removes i_bits bits from the bit buffer
221 *****************************************************************************
222 * - i_bits <= i_available
223 * - i_bits < 32 (because (u32 << 32) <=> (u32 = u32))
224 *****************************************************************************/
225 static __inline__ void DumpBits( bit_stream_t * p_bit_stream, int i_bits )
227 p_bit_stream->fifo.buffer <<= i_bits;
228 p_bit_stream->fifo.i_available -= i_bits;
233 * Philosophy of the second implementation : WORD_LENGTH (usually 32) bits
234 * are read at the same time, thus minimizing the number of p_byte changes.
235 * Bits are read via GetBits() or ShowBits. This is slightly faster. Be
236 * aware that if, in the forthcoming functions, i_bits > 24, the data have to
237 * be already aligned on an 8-bit boundary, or wrong results will be
241 #if (WORD_TYPE != u32)
242 # error Not supported word
245 /*****************************************************************************
246 * ShowBits : return i_bits bits from the bit stream
247 *****************************************************************************/
248 static __inline__ WORD_TYPE ShowWord( bit_stream_t * p_bit_stream )
250 if( p_bit_stream->p_byte <= p_bit_stream->p_end - sizeof(WORD_TYPE) )
252 return( swab32( *((WORD_TYPE *)p_bit_stream->p_byte) ) );
255 p_bit_stream->pf_next_data_packet( p_bit_stream );
256 return( swab32( *((WORD_TYPE *)p_bit_stream->p_byte) ) );
259 static __inline__ WORD_TYPE ShowBits( bit_stream_t * p_bit_stream, int i_bits )
261 if( p_bit_stream->fifo.i_available >= i_bits )
263 return( p_bit_stream->fifo.buffer >> (8 * sizeof(WORD_TYPE) - i_bits) );
266 return( (p_bit_stream->fifo.buffer |
267 (ShowWord( p_bit_stream ) >> p_bit_stream->fifo.i_available))
268 >> (8 * sizeof(WORD_TYPE) - i_bits) );
271 /*****************************************************************************
272 * GetWord : returns the next word to be read
273 *****************************************************************************/
274 static __inline__ WORD_TYPE GetWord( bit_stream_t * p_bit_stream )
276 if( p_bit_stream->p_byte <= p_bit_stream->p_end - sizeof(WORD_TYPE) )
278 return( swab32( *(((WORD_TYPE *)p_bit_stream->p_byte)++) ) );
282 p_bit_stream->pf_next_data_packet( p_bit_stream );
283 return( swab32( *(((WORD_TYPE *)p_bit_stream->p_byte)++) ) );
287 /*****************************************************************************
288 * RemoveBits : removes i_bits bits from the bit buffer
289 * XXX: do not use for 32 bits, see RemoveBits32
290 *****************************************************************************/
291 static __inline__ void RemoveBits( bit_stream_t * p_bit_stream, int i_bits )
293 p_bit_stream->fifo.i_available -= i_bits;
295 if( p_bit_stream->fifo.i_available >= 0 )
297 p_bit_stream->fifo.buffer <<= i_bits;
300 p_bit_stream->fifo.buffer = GetWord( p_bit_stream )
301 << ( -p_bit_stream->fifo.i_available );
302 p_bit_stream->fifo.i_available += sizeof(WORD_TYPE) * 8;
305 /*****************************************************************************
306 * RemoveBits32 : removes 32 bits from the bit buffer (and as a side effect,
308 *****************************************************************************/
309 static __inline__ void RemoveBits32( bit_stream_t * p_bit_stream )
311 if( p_bit_stream->fifo.i_available )
313 p_bit_stream->fifo.buffer = GetWord( p_bit_stream )
314 << (32 - p_bit_stream->fifo.i_available);
318 p_bit_stream->fifo.buffer = GetWord( p_bit_stream );
322 /*****************************************************************************
323 * GetBits : returns i_bits bits from the bit stream and removes them
324 * XXX: do not use for 32 bits, see GetBits32
325 *****************************************************************************/
326 static __inline__ WORD_TYPE GetBits( bit_stream_t * p_bit_stream, int i_bits )
330 p_bit_stream->fifo.i_available -= i_bits;
331 if( p_bit_stream->fifo.i_available >= 0 )
333 i_result = p_bit_stream->fifo.buffer >> (8 * sizeof(WORD_TYPE) - i_bits);
334 p_bit_stream->fifo.buffer <<= i_bits;
338 i_result = p_bit_stream->fifo.buffer >> (8 * sizeof(WORD_TYPE) - i_bits);
339 p_bit_stream->fifo.buffer = GetWord( p_bit_stream );
340 i_result |= p_bit_stream->fifo.buffer
341 >> (8 * sizeof(WORD_TYPE)
342 + p_bit_stream->fifo.i_available);
343 p_bit_stream->fifo.buffer <<= ( -p_bit_stream->fifo.i_available );
344 p_bit_stream->fifo.i_available += sizeof(WORD_TYPE) * 8;
349 /*****************************************************************************
350 * GetBits32 : returns 32 bits from the bit stream and removes them
351 *****************************************************************************/
352 static __inline__ WORD_TYPE GetBits32( bit_stream_t * p_bit_stream )
356 i_result = p_bit_stream->fifo.buffer;
357 p_bit_stream->fifo.buffer = GetWord( p_bit_stream );
359 i_result |= p_bit_stream->fifo.buffer
360 >> (p_bit_stream->fifo.i_available);
361 if( p_bit_stream->fifo.i_available )
363 p_bit_stream->fifo.buffer <<= (8 * sizeof(WORD_TYPE)
364 - p_bit_stream->fifo.i_available);
370 /*****************************************************************************
371 * RealignBits : realigns the bit buffer on an 8-bit boundary
372 *****************************************************************************/
373 static __inline__ void RealignBits( bit_stream_t * p_bit_stream )
375 p_bit_stream->fifo.buffer <<= (p_bit_stream->fifo.i_available & 0x7);
376 p_bit_stream->fifo.i_available &= ~0x7;
381 * Philosophy of the third implementation : the decoder asks for n bytes,
382 * and we will copy them in its buffer.
385 /*****************************************************************************
386 * GetChunk : reads a large chunk of data
387 *****************************************************************************
388 * The position in the stream must be byte-aligned, if unsure call
389 * RealignBits(). p_buffer must to a buffer at least as big as i_buf_len
390 * otherwise your code will crash.
391 *****************************************************************************/
392 static __inline__ void GetChunk( bit_stream_t * p_bit_stream,
393 byte_t * p_buffer, size_t i_buf_len )
395 ptrdiff_t i_available;
397 if( (i_available = p_bit_stream->p_end - p_bit_stream->p_byte)
400 memcpy( p_buffer, p_bit_stream->p_byte, i_buf_len );
401 p_bit_stream->p_byte += i_buf_len;
407 memcpy( p_buffer, p_bit_stream->p_byte, i_available );
408 p_bit_stream->p_byte = p_bit_stream->p_end;
409 p_buffer += i_available;
410 i_buf_len -= i_available;
411 p_bit_stream->pf_next_data_packet( p_bit_stream );
413 while( (i_available = p_bit_stream->p_end - p_bit_stream->p_byte)
418 memcpy( p_buffer, p_bit_stream->p_byte, i_buf_len );
419 p_bit_stream->p_byte += i_buf_len;
426 * Communication interface between input and decoders
429 /*****************************************************************************
431 *****************************************************************************
432 * Standard pointers given to the decoders as a toolbox.
433 *****************************************************************************/
434 typedef struct decoder_config_s
437 u8 i_type; /* type of the elementary stream */
439 struct stream_ctrl_s * p_stream_ctrl;
440 struct decoder_fifo_s * p_decoder_fifo;
441 void (* pf_init_bit_stream)( struct bit_stream_s *,
442 struct decoder_fifo_s * );
445 /*****************************************************************************
447 *****************************************************************************
448 * Pointers given to video decoders threads.
449 *****************************************************************************/
450 struct vout_thread_s;
452 typedef struct vdec_config_s
454 struct vout_thread_s * p_vout;
456 struct picture_s * (* pf_create_picture)( struct vout_thread_s *,
457 int i_type, int i_width,
459 void (* pf_destroy_picture)( struct vout_thread_s *,
460 struct picture_s * );
461 void (* pf_display_picture)( struct vout_thread_s *,
462 struct picture_s * );
463 void (* pf_date_picture)( struct vout_thread_s *,
464 struct picture_s *, mtime_t date );
465 void (* pf_link_picture)( struct vout_thread_s *,
466 struct picture_s *, mtime_t date );
467 void (* pf_unlink_picture)( struct vout_thread_s *,
468 struct picture_s *, mtime_t date );
469 struct subpicture_s *(* pf_create_subpicture)( struct vout_thread_s *,
470 int i_type, int i_size );
471 void (* pf_destroy_subpicture)( struct vout_thread_s *,
472 struct subpicture_s * );
473 void (* pf_display_subpicture)( struct vout_thread_s *,
474 struct subpicture_s * );
476 decoder_config_t decoder_config;
479 /*****************************************************************************
481 *****************************************************************************
482 * Pointers given to audio decoders threads.
483 *****************************************************************************/
484 struct aout_thread_s;
486 typedef struct adec_config_s
488 struct aout_thread_s * p_aout;
490 struct aout_fifo_s * (* pf_create_fifo)( struct aout_thread_s *,
491 struct aout_fifo_s * );
492 void (* pf_destroy_fifo)( struct aout_thread_s *);
494 decoder_config_t decoder_config;
499 * Communication interface between decoders and input
502 /*****************************************************************************
503 * decoder_capabilities_t
504 *****************************************************************************
505 * Structure returned by a call to GetCapabilities() of the decoder.
506 *****************************************************************************/
507 typedef struct decoder_capabilities_s
510 u8 i_stream_type; /* == i_type in es_descriptor_t */
511 int i_weight; /* for a given stream type, the decoder
512 * with higher weight will be spawned */
514 vlc_thread_t (* pf_create_thread)( void * );
515 } decoder_capabilities_t;