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 1.69 2002/08/12 22:12:50 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 #ifndef _VLC_INPUT_EXT_DEC_H
26 #define _VLC_INPUT_EXT_DEC_H 1
28 /* ES streams types - see ISO/IEC 13818-1 table 2-29 numbers.
29 * these values are used in src/input/mpeg_system.c, and in
30 * the following plugins: mpeg_ts, mpeg_ts_dvbpsi, input_satellite. */
31 #define MPEG1_VIDEO_ES 0x01
32 #define MPEG2_VIDEO_ES 0x02
33 #define MPEG1_AUDIO_ES 0x03
34 #define MPEG2_AUDIO_ES 0x04
35 #define A52_AUDIO_ES 0x81
36 /* These ones might violate the norm : */
37 #define DVD_SPU_ES 0x82
38 #define LPCM_AUDIO_ES 0x83
40 /* Structures exported to the decoders */
42 /*****************************************************************************
44 *****************************************************************************
45 * Describe a data packet.
46 *****************************************************************************/
49 /* Used to chain the packets that carry data for a same PES or PSI */
50 data_packet_t * p_next;
52 /* start of the PS or TS packet */
53 byte_t * p_demux_start;
54 /* start of the PES payload in this packet */
55 byte_t * p_payload_start;
56 byte_t * p_payload_end; /* guess ? :-) */
57 /* is the packet messed up ? */
58 vlc_bool_t b_discard_payload;
60 /* pointer to the real data */
61 data_buffer_t * p_buffer;
64 /*****************************************************************************
66 *****************************************************************************
67 * Describes an PES packet, with its properties, and pointers to the TS packets
69 *****************************************************************************/
72 /* Chained list to the next PES packet (depending on the context) */
73 pes_packet_t * p_next;
76 vlc_bool_t b_data_alignment; /* used to find the beginning of
77 * a video or audio unit */
78 vlc_bool_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 reading pace (see stream_control.h) */
85 unsigned int i_pes_size; /* size of the current PES packet */
87 /* Chained list to packets */
88 data_packet_t * p_first; /* The first packet contained by this
89 * PES (used by decoders). */
90 data_packet_t * p_last; /* The last packet contained by this
91 * PES (used by the buffer allocator) */
92 unsigned int i_nb_data; /* Number of data packets in the chained list */
95 /*****************************************************************************
97 *****************************************************************************
98 * This rotative FIFO contains PES packets that are to be decoded.
99 *****************************************************************************/
100 struct decoder_fifo_t
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 input_buffers_t *p_packets_mgt; /* packets management services data */
116 /* Standard pointers given to the decoders as a toolbox. */
118 vlc_fourcc_t i_fourcc;
119 es_sys_t * p_demux_data;
120 stream_ctrl_t * p_stream_ctrl;
121 sout_instance_t * p_sout;
123 /* Module properties */
125 int ( * pf_run ) ( decoder_fifo_t * );
128 /*****************************************************************************
129 * bit_fifo_t : bit fifo descriptor
130 *****************************************************************************
131 * This type describes a bit fifo used to store bits while working with the
132 * input stream at the bit level.
133 *****************************************************************************/
134 typedef u32 WORD_TYPE;
136 typedef struct bit_fifo_t
138 /* This unsigned integer allows us to work at the bit level. This buffer
139 * can contain 32 bits, and the used space can be found on the MSb's side
140 * and the available space on the LSb's side. */
143 /* Number of bits available in the bit buffer */
148 /*****************************************************************************
149 * bit_stream_t : bit stream descriptor
150 *****************************************************************************
151 * This type, based on a PES stream, includes all the structures needed to
152 * handle the input stream like a bit stream.
153 *****************************************************************************/
164 /* The decoder fifo contains the data of the PES stream */
165 decoder_fifo_t * p_decoder_fifo;
167 /* Callback to the decoder used when changing data packets ; set
168 * to NULL if your decoder doesn't need it. */
169 void (* pf_bitstream_callback)( bit_stream_t *, vlc_bool_t );
170 /* Optional argument to the callback */
171 void * p_callback_arg;
176 mtime_t i_pts, i_dts;
177 byte_t * p_pts_validity;
182 /* Current data packet (in the current PES packet of the PES stream) */
183 data_packet_t * p_data;
184 /* Pointer to the next byte that is to be read (in the current packet) */
186 /* Pointer to the last byte that is to be read (in the current packet */
188 /* Temporary buffer in case we're not aligned when changing data packets */
189 WORD_TYPE i_showbits_buffer;
190 data_packet_t showbits_data;
193 /*****************************************************************************
194 * Inline functions used by the decoders to read bit_stream_t
195 *****************************************************************************/
198 * DISCUSSION : How to use the bit_stream structures
200 * sizeof(WORD_TYPE) (usually 32) bits are read at the same time, thus
201 * minimizing the number of p_byte changes.
202 * Bits are read via GetBits() or ShowBits.
204 * XXX : Be aware that if, in the forthcoming functions, i_bits > 24,
205 * the data have to be already aligned on an 8-bit boundary, or wrong
206 * results will be returned. Use RealignBits() if unsure.
209 #if (WORD_TYPE == u32)
210 # define WORD_AT U32_AT
211 # define WORD_SIGNED s32
212 #elif (WORD_TYPE == u64)
213 # define WORD_AT U64_AT
214 # define WORD_SIGNED s64
216 # error Unsupported WORD_TYPE
219 /*****************************************************************************
220 * Prototypes from input_ext-dec.c
221 *****************************************************************************/
222 VLC_EXPORT( void, InitBitstream, ( bit_stream_t *, decoder_fifo_t *, void ( * )( bit_stream_t *, vlc_bool_t ), void * p_callback_arg ) );
223 VLC_EXPORT( vlc_bool_t, NextDataPacket, ( decoder_fifo_t *, data_packet_t ** ) );
224 VLC_EXPORT( void, BitstreamNextDataPacket, ( bit_stream_t * ) );
225 VLC_EXPORT( u32, UnalignedShowBits, ( bit_stream_t *, unsigned int ) );
226 VLC_EXPORT( void, UnalignedRemoveBits, ( bit_stream_t * ) );
227 VLC_EXPORT( u32, UnalignedGetBits, ( bit_stream_t *, unsigned int ) );
228 VLC_EXPORT( void, CurrentPTS, ( bit_stream_t *, mtime_t *, mtime_t * ) );
230 /*****************************************************************************
231 * AlignWord : fill in the bit buffer so that the byte pointer be aligned
232 * on a word boundary (XXX: there must be at least sizeof(WORD_TYPE) - 1
233 * empty bytes in the bit buffer)
234 *****************************************************************************/
235 static inline void AlignWord( bit_stream_t * p_bit_stream )
237 while( (ptrdiff_t)p_bit_stream->p_byte
238 & (sizeof(WORD_TYPE) - 1) )
240 if( p_bit_stream->p_byte < p_bit_stream->p_end )
242 p_bit_stream->fifo.buffer |= *(p_bit_stream->p_byte++)
243 << (8 * sizeof(WORD_TYPE) - 8
244 - p_bit_stream->fifo.i_available);
245 p_bit_stream->fifo.i_available += 8;
249 BitstreamNextDataPacket( p_bit_stream );
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;
258 /*****************************************************************************
259 * ShowBits : return i_bits bits from the bit stream
260 *****************************************************************************/
261 static inline u32 ShowBits( bit_stream_t * p_bit_stream, unsigned int i_bits )
263 if( p_bit_stream->fifo.i_available >= i_bits )
265 return( p_bit_stream->fifo.buffer >> (8 * sizeof(WORD_TYPE) - i_bits) );
268 if( p_bit_stream->p_byte <= p_bit_stream->p_end - sizeof(WORD_TYPE) )
270 return( (p_bit_stream->fifo.buffer |
271 (WORD_AT( p_bit_stream->p_byte )
272 >> p_bit_stream->fifo.i_available))
273 >> (8 * sizeof(WORD_TYPE) - i_bits) );
276 return( UnalignedShowBits( p_bit_stream, i_bits ) );
279 /*****************************************************************************
280 * ShowSignedBits : return i_bits bits from the bit stream, using signed
282 *****************************************************************************/
283 static inline s32 ShowSignedBits( bit_stream_t * p_bit_stream,
284 unsigned int i_bits )
286 if( p_bit_stream->fifo.i_available >= i_bits )
288 return( (WORD_SIGNED)p_bit_stream->fifo.buffer
289 >> (8 * sizeof(WORD_TYPE) - i_bits) );
292 /* You can probably do something a little faster, but now I'm tired. */
293 return( (WORD_SIGNED)(ShowBits( p_bit_stream, i_bits ) << (32 - i_bits))
297 /*****************************************************************************
298 * RemoveBits : removes i_bits bits from the bit buffer
299 * XXX: do not use for 32 bits, see RemoveBits32
300 *****************************************************************************/
301 static inline void RemoveBits( bit_stream_t * p_bit_stream,
302 unsigned int i_bits )
304 p_bit_stream->fifo.i_available -= i_bits;
306 if( p_bit_stream->fifo.i_available >= 0 )
308 p_bit_stream->fifo.buffer <<= i_bits;
312 if( p_bit_stream->p_byte <= p_bit_stream->p_end - sizeof(WORD_TYPE) )
314 p_bit_stream->fifo.buffer = WORD_AT( p_bit_stream->p_byte )
315 << ( -p_bit_stream->fifo.i_available );
316 p_bit_stream->p_byte =
317 (byte_t *) ( ((WORD_TYPE *)p_bit_stream->p_byte) + 1 );
318 p_bit_stream->fifo.i_available += sizeof(WORD_TYPE) * 8;
322 UnalignedRemoveBits( p_bit_stream );
325 /*****************************************************************************
326 * RemoveBits32 : removes 32 bits from the bit buffer (and as a side effect,
328 *****************************************************************************/
329 #if (WORD_TYPE == u32)
330 static inline void RemoveBits32( bit_stream_t * p_bit_stream )
332 if( p_bit_stream->p_byte <= p_bit_stream->p_end - sizeof(WORD_TYPE) )
334 if( p_bit_stream->fifo.i_available )
336 p_bit_stream->fifo.buffer = WORD_AT( p_bit_stream->p_byte )
337 << (32 - p_bit_stream->fifo.i_available);
338 p_bit_stream->p_byte =
339 (byte_t *) ( ((WORD_TYPE *)p_bit_stream->p_byte) + 1 );
343 p_bit_stream->p_byte =
344 (byte_t *) ( ((WORD_TYPE *)p_bit_stream->p_byte) + 1 );
348 p_bit_stream->fifo.i_available -= 32;
349 UnalignedRemoveBits( p_bit_stream );
352 # define RemoveBits32( p_bit_stream ) RemoveBits( p_bit_stream, 32 )
355 /*****************************************************************************
356 * GetBits : returns i_bits bits from the bit stream and removes them
357 * XXX: do not use for 32 bits, see GetBits32
358 *****************************************************************************/
359 static inline u32 GetBits( bit_stream_t * p_bit_stream, unsigned int i_bits )
363 p_bit_stream->fifo.i_available -= i_bits;
365 if( p_bit_stream->fifo.i_available >= 0 )
367 i_result = p_bit_stream->fifo.buffer
368 >> (8 * sizeof(WORD_TYPE) - i_bits);
369 p_bit_stream->fifo.buffer <<= i_bits;
373 if( p_bit_stream->p_byte <= p_bit_stream->p_end - sizeof(WORD_TYPE) )
375 i_result = p_bit_stream->fifo.buffer
376 >> (8 * sizeof(WORD_TYPE) - i_bits);
377 p_bit_stream->fifo.buffer = WORD_AT( p_bit_stream->p_byte );
378 p_bit_stream->p_byte =
379 (byte_t *) ( ((WORD_TYPE *)p_bit_stream->p_byte) + 1 );
380 i_result |= p_bit_stream->fifo.buffer
381 >> (8 * sizeof(WORD_TYPE)
382 + p_bit_stream->fifo.i_available);
383 p_bit_stream->fifo.buffer <<= ( -p_bit_stream->fifo.i_available );
384 p_bit_stream->fifo.i_available += sizeof(WORD_TYPE) * 8;
388 return UnalignedGetBits( p_bit_stream, i_bits );
391 /*****************************************************************************
392 * GetSignedBits : returns i_bits bits from the bit stream and removes them,
393 * using signed arithmetic
394 * XXX: do not use for 32 bits
395 *****************************************************************************/
396 static inline s32 GetSignedBits( bit_stream_t * p_bit_stream,
397 unsigned int i_bits )
399 if( p_bit_stream->fifo.i_available >= i_bits )
403 p_bit_stream->fifo.i_available -= i_bits;
404 i_result = (WORD_SIGNED)p_bit_stream->fifo.buffer
405 >> (8 * sizeof(WORD_TYPE) - i_bits);
406 p_bit_stream->fifo.buffer <<= i_bits;
410 /* You can probably do something a little faster, but now I'm tired. */
411 return( (WORD_SIGNED)(GetBits( p_bit_stream, i_bits ) << (32 - i_bits))
415 /*****************************************************************************
416 * GetBits32 : returns 32 bits from the bit stream and removes them
417 *****************************************************************************/
418 #if (WORD_TYPE == u32)
419 static inline u32 GetBits32( bit_stream_t * p_bit_stream )
423 if( p_bit_stream->fifo.i_available == 32 )
425 p_bit_stream->fifo.i_available = 0;
426 i_result = p_bit_stream->fifo.buffer;
427 p_bit_stream->fifo.buffer = 0;
431 if( p_bit_stream->p_byte <= p_bit_stream->p_end - sizeof(WORD_TYPE) )
433 if( p_bit_stream->fifo.i_available )
435 i_result = p_bit_stream->fifo.buffer;
436 p_bit_stream->fifo.buffer = WORD_AT( p_bit_stream->p_byte );
437 p_bit_stream->p_byte =
438 (byte_t *) ( ((WORD_TYPE *)p_bit_stream->p_byte) + 1 );
439 i_result |= p_bit_stream->fifo.buffer
440 >> (p_bit_stream->fifo.i_available);
441 p_bit_stream->fifo.buffer <<= (32 - p_bit_stream->fifo.i_available);
445 i_result = WORD_AT( p_bit_stream->p_byte );
446 p_bit_stream->p_byte =
447 (byte_t *) ( ((WORD_TYPE *)p_bit_stream->p_byte) + 1 );
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 p_bit_stream->p_decoder_fifo->p_vlc->pf_memcpy( p_buffer,
494 p_bit_stream->p_byte, i_buf_len );
495 p_bit_stream->p_byte += i_buf_len;
501 p_bit_stream->p_decoder_fifo->p_vlc->pf_memcpy( p_buffer,
502 p_bit_stream->p_byte, i_available );
503 p_bit_stream->p_byte = p_bit_stream->p_end;
504 p_buffer += i_available;
505 i_buf_len -= i_available;
506 BitstreamNextDataPacket( p_bit_stream );
507 if( p_bit_stream->p_decoder_fifo->b_die )
510 while( (i_available = p_bit_stream->p_end - p_bit_stream->p_byte)
515 p_bit_stream->p_decoder_fifo->p_vlc->pf_memcpy( p_buffer,
516 p_bit_stream->p_byte, i_buf_len );
517 p_bit_stream->p_byte += i_buf_len;
521 if( p_bit_stream->p_byte <= p_bit_stream->p_end - sizeof(WORD_TYPE) )
523 AlignWord( p_bit_stream );
529 * Communication interface between input and decoders
532 /*****************************************************************************
533 * Prototypes from input_dec.c
534 *****************************************************************************/
535 VLC_EXPORT( void, DecoderError, ( decoder_fifo_t * p_fifo ) );
537 #endif /* "input_ext-dec.h" */