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 1.64 2002/07/23 00:39:16 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 #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 AC3_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;
120 stream_ctrl_t * p_stream_ctrl;
123 /*****************************************************************************
124 * bit_fifo_t : bit fifo descriptor
125 *****************************************************************************
126 * This type describes a bit fifo used to store bits while working with the
127 * input stream at the bit level.
128 *****************************************************************************/
129 typedef u32 WORD_TYPE;
131 typedef struct bit_fifo_t
133 /* This unsigned integer allows us to work at the bit level. This buffer
134 * can contain 32 bits, and the used space can be found on the MSb's side
135 * and the available space on the LSb's side. */
138 /* Number of bits available in the bit buffer */
143 /*****************************************************************************
144 * bit_stream_t : bit stream descriptor
145 *****************************************************************************
146 * This type, based on a PES stream, includes all the structures needed to
147 * handle the input stream like a bit stream.
148 *****************************************************************************/
159 /* The decoder fifo contains the data of the PES stream */
160 decoder_fifo_t * p_decoder_fifo;
162 /* Callback to the decoder used when changing data packets ; set
163 * to NULL if your decoder doesn't need it. */
164 void (* pf_bitstream_callback)( bit_stream_t *, vlc_bool_t );
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 *****************************************************************************/
217 VLC_EXPORT( void, InitBitstream, ( bit_stream_t *, decoder_fifo_t *, void ( * )( bit_stream_t *, vlc_bool_t ), void * p_callback_arg ) );
218 VLC_EXPORT( vlc_bool_t, NextDataPacket, ( decoder_fifo_t *, data_packet_t ** ) );
219 VLC_EXPORT( void, BitstreamNextDataPacket, ( bit_stream_t * ) );
220 VLC_EXPORT( u32, UnalignedShowBits, ( bit_stream_t *, unsigned int ) );
221 VLC_EXPORT( void, UnalignedRemoveBits, ( bit_stream_t * ) );
222 VLC_EXPORT( u32, UnalignedGetBits, ( bit_stream_t *, unsigned int ) );
223 VLC_EXPORT( void, CurrentPTS, ( bit_stream_t *, mtime_t *, mtime_t * ) );
225 /*****************************************************************************
226 * AlignWord : fill in the bit buffer so that the byte pointer be aligned
227 * on a word boundary (XXX: there must be at least sizeof(WORD_TYPE) - 1
228 * empty bytes in the bit buffer)
229 *****************************************************************************/
230 static inline void AlignWord( bit_stream_t * p_bit_stream )
232 while( (ptrdiff_t)p_bit_stream->p_byte
233 & (sizeof(WORD_TYPE) - 1) )
235 if( p_bit_stream->p_byte < p_bit_stream->p_end )
237 p_bit_stream->fifo.buffer |= *(p_bit_stream->p_byte++)
238 << (8 * sizeof(WORD_TYPE) - 8
239 - p_bit_stream->fifo.i_available);
240 p_bit_stream->fifo.i_available += 8;
244 BitstreamNextDataPacket( p_bit_stream );
245 p_bit_stream->fifo.buffer |= *(p_bit_stream->p_byte++)
246 << (8 * sizeof(WORD_TYPE) - 8
247 - p_bit_stream->fifo.i_available);
248 p_bit_stream->fifo.i_available += 8;
253 /*****************************************************************************
254 * ShowBits : return i_bits bits from the bit stream
255 *****************************************************************************/
256 static inline u32 ShowBits( bit_stream_t * p_bit_stream, unsigned int i_bits )
258 if( p_bit_stream->fifo.i_available >= i_bits )
260 return( p_bit_stream->fifo.buffer >> (8 * sizeof(WORD_TYPE) - i_bits) );
263 if( p_bit_stream->p_byte <= p_bit_stream->p_end - sizeof(WORD_TYPE) )
265 return( (p_bit_stream->fifo.buffer |
266 (WORD_AT( p_bit_stream->p_byte )
267 >> p_bit_stream->fifo.i_available))
268 >> (8 * sizeof(WORD_TYPE) - i_bits) );
271 return( UnalignedShowBits( p_bit_stream, i_bits ) );
274 /*****************************************************************************
275 * ShowSignedBits : return i_bits bits from the bit stream, using signed
277 *****************************************************************************/
278 static inline s32 ShowSignedBits( bit_stream_t * p_bit_stream,
279 unsigned int i_bits )
281 if( p_bit_stream->fifo.i_available >= i_bits )
283 return( (WORD_SIGNED)p_bit_stream->fifo.buffer
284 >> (8 * sizeof(WORD_TYPE) - i_bits) );
287 /* You can probably do something a little faster, but now I'm tired. */
288 return( (WORD_SIGNED)(ShowBits( p_bit_stream, i_bits ) << (32 - i_bits))
292 /*****************************************************************************
293 * RemoveBits : removes i_bits bits from the bit buffer
294 * XXX: do not use for 32 bits, see RemoveBits32
295 *****************************************************************************/
296 static inline void RemoveBits( bit_stream_t * p_bit_stream,
297 unsigned int i_bits )
299 p_bit_stream->fifo.i_available -= i_bits;
301 if( p_bit_stream->fifo.i_available >= 0 )
303 p_bit_stream->fifo.buffer <<= i_bits;
307 if( p_bit_stream->p_byte <= p_bit_stream->p_end - sizeof(WORD_TYPE) )
309 p_bit_stream->fifo.buffer = WORD_AT( p_bit_stream->p_byte )
310 << ( -p_bit_stream->fifo.i_available );
311 ((WORD_TYPE *)p_bit_stream->p_byte)++;
312 p_bit_stream->fifo.i_available += sizeof(WORD_TYPE) * 8;
316 UnalignedRemoveBits( p_bit_stream );
319 /*****************************************************************************
320 * RemoveBits32 : removes 32 bits from the bit buffer (and as a side effect,
322 *****************************************************************************/
323 #if (WORD_TYPE == u32)
324 static inline void RemoveBits32( bit_stream_t * p_bit_stream )
326 if( p_bit_stream->p_byte <= p_bit_stream->p_end - sizeof(WORD_TYPE) )
328 if( p_bit_stream->fifo.i_available )
330 p_bit_stream->fifo.buffer = WORD_AT( p_bit_stream->p_byte )
331 << (32 - p_bit_stream->fifo.i_available);
332 ((WORD_TYPE *)p_bit_stream->p_byte)++;
336 ((WORD_TYPE *)p_bit_stream->p_byte)++;
340 p_bit_stream->fifo.i_available -= 32;
341 UnalignedRemoveBits( p_bit_stream );
344 # define RemoveBits32( p_bit_stream ) RemoveBits( p_bit_stream, 32 )
347 /*****************************************************************************
348 * GetBits : returns i_bits bits from the bit stream and removes them
349 * XXX: do not use for 32 bits, see GetBits32
350 *****************************************************************************/
351 static inline u32 GetBits( bit_stream_t * p_bit_stream, unsigned int i_bits )
355 p_bit_stream->fifo.i_available -= i_bits;
357 if( p_bit_stream->fifo.i_available >= 0 )
359 i_result = p_bit_stream->fifo.buffer
360 >> (8 * sizeof(WORD_TYPE) - i_bits);
361 p_bit_stream->fifo.buffer <<= i_bits;
365 if( p_bit_stream->p_byte <= p_bit_stream->p_end - sizeof(WORD_TYPE) )
367 i_result = p_bit_stream->fifo.buffer
368 >> (8 * sizeof(WORD_TYPE) - i_bits);
369 p_bit_stream->fifo.buffer = WORD_AT( p_bit_stream->p_byte );
370 ((WORD_TYPE *)p_bit_stream->p_byte)++;
371 i_result |= p_bit_stream->fifo.buffer
372 >> (8 * sizeof(WORD_TYPE)
373 + p_bit_stream->fifo.i_available);
374 p_bit_stream->fifo.buffer <<= ( -p_bit_stream->fifo.i_available );
375 p_bit_stream->fifo.i_available += sizeof(WORD_TYPE) * 8;
379 return UnalignedGetBits( p_bit_stream, i_bits );
382 /*****************************************************************************
383 * GetSignedBits : returns i_bits bits from the bit stream and removes them,
384 * using signed arithmetic
385 * XXX: do not use for 32 bits
386 *****************************************************************************/
387 static inline s32 GetSignedBits( bit_stream_t * p_bit_stream,
388 unsigned int i_bits )
390 if( p_bit_stream->fifo.i_available >= i_bits )
394 p_bit_stream->fifo.i_available -= i_bits;
395 i_result = (WORD_SIGNED)p_bit_stream->fifo.buffer
396 >> (8 * sizeof(WORD_TYPE) - i_bits);
397 p_bit_stream->fifo.buffer <<= i_bits;
401 /* You can probably do something a little faster, but now I'm tired. */
402 return( (WORD_SIGNED)(GetBits( p_bit_stream, i_bits ) << (32 - i_bits))
406 /*****************************************************************************
407 * GetBits32 : returns 32 bits from the bit stream and removes them
408 *****************************************************************************/
409 #if (WORD_TYPE == u32)
410 static inline u32 GetBits32( bit_stream_t * p_bit_stream )
414 if( p_bit_stream->fifo.i_available == 32 )
416 p_bit_stream->fifo.i_available = 0;
417 i_result = p_bit_stream->fifo.buffer;
418 p_bit_stream->fifo.buffer = 0;
422 if( p_bit_stream->p_byte <= p_bit_stream->p_end - sizeof(WORD_TYPE) )
424 if( p_bit_stream->fifo.i_available )
426 i_result = p_bit_stream->fifo.buffer;
427 p_bit_stream->fifo.buffer = WORD_AT( p_bit_stream->p_byte );
428 ((WORD_TYPE *)p_bit_stream->p_byte)++;
429 i_result |= p_bit_stream->fifo.buffer
430 >> (p_bit_stream->fifo.i_available);
431 p_bit_stream->fifo.buffer <<= (32 - p_bit_stream->fifo.i_available);
435 i_result = WORD_AT( p_bit_stream->p_byte );
436 ((WORD_TYPE *)p_bit_stream->p_byte)++;
440 p_bit_stream->fifo.i_available -= 32;
441 return UnalignedGetBits( p_bit_stream, 32 );
444 # define GetBits32( p_bit_stream ) GetBits( p_bit_stream, 32 )
447 /*****************************************************************************
448 * RealignBits : realigns the bit buffer on an 8-bit boundary
449 *****************************************************************************/
450 static inline void RealignBits( bit_stream_t * p_bit_stream )
452 p_bit_stream->fifo.buffer <<= (p_bit_stream->fifo.i_available & 0x7);
453 p_bit_stream->fifo.i_available &= ~0x7;
457 /*****************************************************************************
458 * GetChunk : reads a large chunk of data
459 *****************************************************************************
460 * The position in the stream must be byte-aligned, if unsure call
461 * RealignBits(). p_buffer must point to a buffer at least as big as i_buf_len
462 * otherwise your code will crash.
463 *****************************************************************************/
464 static inline void GetChunk( bit_stream_t * p_bit_stream,
465 byte_t * p_buffer, size_t i_buf_len )
467 ptrdiff_t i_available;
469 /* We need to take care because i_buf_len may be < 4. */
470 while( p_bit_stream->fifo.i_available > 0 && i_buf_len )
472 *p_buffer = p_bit_stream->fifo.buffer >> (8 * sizeof(WORD_TYPE) - 8);
475 p_bit_stream->fifo.buffer <<= 8;
476 p_bit_stream->fifo.i_available -= 8;
479 if( (i_available = p_bit_stream->p_end - p_bit_stream->p_byte)
482 p_bit_stream->p_decoder_fifo->p_vlc->pf_memcpy( p_buffer,
483 p_bit_stream->p_byte, i_buf_len );
484 p_bit_stream->p_byte += i_buf_len;
490 p_bit_stream->p_decoder_fifo->p_vlc->pf_memcpy( p_buffer,
491 p_bit_stream->p_byte, i_available );
492 p_bit_stream->p_byte = p_bit_stream->p_end;
493 p_buffer += i_available;
494 i_buf_len -= i_available;
495 BitstreamNextDataPacket( p_bit_stream );
496 if( p_bit_stream->p_decoder_fifo->b_die )
499 while( (i_available = p_bit_stream->p_end - p_bit_stream->p_byte)
504 p_bit_stream->p_decoder_fifo->p_vlc->pf_memcpy( p_buffer,
505 p_bit_stream->p_byte, i_buf_len );
506 p_bit_stream->p_byte += i_buf_len;
510 if( p_bit_stream->p_byte <= p_bit_stream->p_end - sizeof(WORD_TYPE) )
512 AlignWord( p_bit_stream );
518 * Communication interface between input and decoders
521 /*****************************************************************************
522 * Prototypes from input_dec.c
523 *****************************************************************************/
524 VLC_EXPORT( void, DecoderError, ( decoder_fifo_t * p_fifo ) );
526 #endif /* "input_ext-dec.h" */