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 1.79 2003/03/04 13:21:19 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 /* Structures exported to the decoders */
30 /*****************************************************************************
32 *****************************************************************************
33 * Describe a data packet.
34 *****************************************************************************/
37 /* Used to chain the packets that carry data for a same PES or PSI */
38 data_packet_t * p_next;
40 /* start of the PS or TS packet */
41 byte_t * p_demux_start;
42 /* start of the PES payload in this packet */
43 byte_t * p_payload_start;
44 byte_t * p_payload_end; /* guess ? :-) */
45 /* is the packet messed up ? */
46 vlc_bool_t b_discard_payload;
48 /* pointer to the real data */
49 data_buffer_t * p_buffer;
52 /*****************************************************************************
54 *****************************************************************************
55 * Describes an PES packet, with its properties, and pointers to the TS packets
57 *****************************************************************************/
60 /* Chained list to the next PES packet (depending on the context) */
61 pes_packet_t * p_next;
64 vlc_bool_t b_data_alignment; /* used to find the beginning of
65 * a video or audio unit */
66 vlc_bool_t b_discontinuity; /* This packet doesn't follow the
69 mtime_t i_pts; /* PTS for this packet (zero if unset) */
70 mtime_t i_dts; /* DTS for this packet (zero if unset) */
71 int i_rate; /* current reading pace (see stream_control.h) */
73 unsigned int i_pes_size; /* size of the current PES packet */
75 /* Chained list to packets */
76 data_packet_t * p_first; /* The first packet contained by this
77 * PES (used by decoders). */
78 data_packet_t * p_last; /* The last packet contained by this
79 * PES (used by the buffer allocator) */
80 unsigned int i_nb_data; /* Number of data packets in the chained list */
83 /*****************************************************************************
85 *****************************************************************************
86 * This rotative FIFO contains PES packets that are to be decoded.
87 *****************************************************************************/
92 /* Thread structures */
93 vlc_mutex_t data_lock; /* fifo data lock */
94 vlc_cond_t data_wait; /* fifo data conditional variable */
97 pes_packet_t * p_first;
98 pes_packet_t ** pp_last;
99 int i_depth; /* number of PES packets in the stack */
101 /* Communication interface between input and decoders */
102 input_buffers_t *p_packets_mgt; /* packets management services data */
104 /* Standard pointers given to the decoders as a toolbox. */
106 vlc_fourcc_t i_fourcc;
107 es_sys_t * p_demux_data;
108 stream_ctrl_t * p_stream_ctrl;
109 sout_instance_t * p_sout;
110 void * p_waveformatex;
111 void * p_bitmapinfoheader;
113 /* Module properties */
115 int ( * pf_run ) ( decoder_fifo_t * );
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 uint32_t WORD_TYPE;
126 typedef struct bit_fifo_t
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 *****************************************************************************/
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)( bit_stream_t *, vlc_bool_t );
160 /* Optional argument to the callback */
161 void * p_callback_arg;
166 mtime_t i_pts, i_dts;
167 byte_t * p_pts_validity;
172 /* Current PES packet (extracted from the PES stream) */
173 pes_packet_t * p_pes;
174 /* Current data packet (in the current PES packet) */
175 data_packet_t * p_data;
176 /* Pointer to the next byte that is to be read (in the current packet) */
178 /* Pointer to the last byte that is to be read (in the current packet */
180 /* Temporary buffer in case we're not aligned when changing data packets */
181 WORD_TYPE i_showbits_buffer;
182 data_packet_t showbits_data;
185 /*****************************************************************************
186 * Inline functions used by the decoders to read bit_stream_t
187 *****************************************************************************/
190 * DISCUSSION : How to use the bit_stream structures
192 * sizeof(WORD_TYPE) (usually 32) bits are read at the same time, thus
193 * minimizing the number of p_byte changes.
194 * Bits are read via GetBits() or ShowBits.
196 * XXX : Be aware that if, in the forthcoming functions, i_bits > 24,
197 * the data have to be already aligned on an 8-bit boundary, or wrong
198 * results will be returned. Use RealignBits() if unsure.
201 #if (WORD_TYPE == uint32_t)
202 # define WORD_AT U32_AT
203 # define WORD_SIGNED int32_t
204 #elif (WORD_TYPE == uint64_t)
205 # define WORD_AT U64_AT
206 # define WORD_SIGNED int64_t
208 # error Unsupported WORD_TYPE
211 /*****************************************************************************
212 * Prototypes from input_ext-dec.c
213 *****************************************************************************/
214 VLC_EXPORT( void, input_ExtractPES, ( decoder_fifo_t *, pes_packet_t ** ) );
215 VLC_EXPORT( void, input_DeletePES, ( input_buffers_t *, pes_packet_t * ) );
216 VLC_EXPORT( int, InitBitstream, ( bit_stream_t *, decoder_fifo_t *, void ( * )( bit_stream_t *, vlc_bool_t ), void * p_callback_arg ) );
217 VLC_EXPORT( vlc_bool_t, NextDataPacket, ( decoder_fifo_t *, bit_stream_t * ) );
218 VLC_EXPORT( void, BitstreamNextDataPacket, ( bit_stream_t * ) );
219 VLC_EXPORT( uint32_t, UnalignedShowBits, ( bit_stream_t *, unsigned int ) );
220 VLC_EXPORT( void, UnalignedRemoveBits, ( bit_stream_t * ) );
221 VLC_EXPORT( uint32_t, UnalignedGetBits, ( bit_stream_t *, unsigned int ) );
222 VLC_EXPORT( void, CloseBitstream, ( bit_stream_t * ) );
223 VLC_EXPORT( void, CurrentPTS, ( bit_stream_t *, mtime_t *, mtime_t * ) );
224 VLC_EXPORT( void, NextPTS, ( bit_stream_t *, mtime_t *, mtime_t * ) );
226 /*****************************************************************************
227 * AlignWord : fill in the bit buffer so that the byte pointer be aligned
228 * on a word boundary (XXX: there must be at least sizeof(WORD_TYPE) - 1
229 * empty bytes in the bit buffer)
230 *****************************************************************************/
231 static inline void AlignWord( bit_stream_t * p_bit_stream )
233 while( (ptrdiff_t)p_bit_stream->p_byte
234 & (sizeof(WORD_TYPE) - 1) )
236 if( p_bit_stream->p_byte < p_bit_stream->p_end )
238 p_bit_stream->fifo.buffer |= *(p_bit_stream->p_byte++)
239 << (8 * sizeof(WORD_TYPE) - 8
240 - p_bit_stream->fifo.i_available);
241 p_bit_stream->fifo.i_available += 8;
245 BitstreamNextDataPacket( p_bit_stream );
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;
254 /*****************************************************************************
255 * ShowBits : return i_bits bits from the bit stream
256 *****************************************************************************/
257 static inline uint32_t ShowBits( bit_stream_t * p_bit_stream,
258 unsigned int i_bits )
260 if( (unsigned int)p_bit_stream->fifo.i_available >= i_bits )
262 return( p_bit_stream->fifo.buffer >> (8 * sizeof(WORD_TYPE) - i_bits) );
265 if( p_bit_stream->p_byte <= p_bit_stream->p_end - sizeof(WORD_TYPE) )
267 return( (p_bit_stream->fifo.buffer |
268 (WORD_AT( p_bit_stream->p_byte )
269 >> p_bit_stream->fifo.i_available))
270 >> (8 * sizeof(WORD_TYPE) - i_bits) );
273 return( UnalignedShowBits( p_bit_stream, i_bits ) );
276 /*****************************************************************************
277 * ShowSignedBits : return i_bits bits from the bit stream, using signed
279 *****************************************************************************/
280 static inline int32_t ShowSignedBits( bit_stream_t * p_bit_stream,
281 unsigned int i_bits )
283 if( (unsigned int)p_bit_stream->fifo.i_available >= i_bits )
285 return( (WORD_SIGNED)p_bit_stream->fifo.buffer
286 >> (8 * sizeof(WORD_TYPE) - i_bits) );
289 /* You can probably do something a little faster, but now I'm tired. */
290 return( (WORD_SIGNED)(ShowBits( p_bit_stream, i_bits ) << (32 - i_bits))
294 /*****************************************************************************
295 * RemoveBits : removes i_bits bits from the bit buffer
296 * XXX: do not use for 32 bits, see RemoveBits32
297 *****************************************************************************/
298 static inline void RemoveBits( bit_stream_t * p_bit_stream,
299 unsigned int i_bits )
301 p_bit_stream->fifo.i_available -= i_bits;
303 if( p_bit_stream->fifo.i_available >= 0 )
305 p_bit_stream->fifo.buffer <<= i_bits;
309 if( p_bit_stream->p_byte <= p_bit_stream->p_end - sizeof(WORD_TYPE) )
311 p_bit_stream->fifo.buffer = WORD_AT( p_bit_stream->p_byte )
312 << ( -p_bit_stream->fifo.i_available );
313 p_bit_stream->p_byte =
314 (byte_t *) ( ((WORD_TYPE *)p_bit_stream->p_byte) + 1 );
315 p_bit_stream->fifo.i_available += sizeof(WORD_TYPE) * 8;
319 UnalignedRemoveBits( p_bit_stream );
322 /*****************************************************************************
323 * RemoveBits32 : removes 32 bits from the bit buffer (and as a side effect,
325 *****************************************************************************/
326 #if (WORD_TYPE == uint32_t)
327 static inline void RemoveBits32( bit_stream_t * p_bit_stream )
329 if( p_bit_stream->p_byte <= p_bit_stream->p_end - sizeof(WORD_TYPE) )
331 if( p_bit_stream->fifo.i_available )
333 p_bit_stream->fifo.buffer = WORD_AT( p_bit_stream->p_byte )
334 << (32 - p_bit_stream->fifo.i_available);
335 p_bit_stream->p_byte =
336 (byte_t *) ( ((WORD_TYPE *)p_bit_stream->p_byte) + 1 );
340 p_bit_stream->p_byte =
341 (byte_t *) ( ((WORD_TYPE *)p_bit_stream->p_byte) + 1 );
345 p_bit_stream->fifo.i_available -= 32;
346 UnalignedRemoveBits( p_bit_stream );
349 # define RemoveBits32( p_bit_stream ) RemoveBits( p_bit_stream, 32 )
352 /*****************************************************************************
353 * GetBits : returns i_bits bits from the bit stream and removes them
354 * XXX: do not use for 32 bits, see GetBits32
355 *****************************************************************************/
356 static inline uint32_t GetBits( bit_stream_t * p_bit_stream,
357 unsigned int i_bits )
361 p_bit_stream->fifo.i_available -= i_bits;
363 if( p_bit_stream->fifo.i_available >= 0 )
365 i_result = p_bit_stream->fifo.buffer
366 >> (8 * sizeof(WORD_TYPE) - i_bits);
367 p_bit_stream->fifo.buffer <<= i_bits;
371 if( p_bit_stream->p_byte <= p_bit_stream->p_end - sizeof(WORD_TYPE) )
373 i_result = p_bit_stream->fifo.buffer
374 >> (8 * sizeof(WORD_TYPE) - i_bits);
375 p_bit_stream->fifo.buffer = WORD_AT( p_bit_stream->p_byte );
376 p_bit_stream->p_byte =
377 (byte_t *) ( ((WORD_TYPE *)p_bit_stream->p_byte) + 1 );
378 i_result |= p_bit_stream->fifo.buffer
379 >> (8 * sizeof(WORD_TYPE)
380 + p_bit_stream->fifo.i_available);
381 p_bit_stream->fifo.buffer <<= ( -p_bit_stream->fifo.i_available );
382 p_bit_stream->fifo.i_available += sizeof(WORD_TYPE) * 8;
386 return UnalignedGetBits( p_bit_stream, i_bits );
389 /*****************************************************************************
390 * GetSignedBits : returns i_bits bits from the bit stream and removes them,
391 * using signed arithmetic
392 * XXX: do not use for 32 bits
393 *****************************************************************************/
394 static inline int32_t GetSignedBits( bit_stream_t * p_bit_stream,
395 unsigned int i_bits )
397 if( (unsigned int)p_bit_stream->fifo.i_available >= i_bits )
401 p_bit_stream->fifo.i_available -= i_bits;
402 i_result = (WORD_SIGNED)p_bit_stream->fifo.buffer
403 >> (8 * sizeof(WORD_TYPE) - i_bits);
404 p_bit_stream->fifo.buffer <<= i_bits;
408 /* You can probably do something a little faster, but now I'm tired. */
409 return( (WORD_SIGNED)(GetBits( p_bit_stream, i_bits ) << (32 - i_bits))
413 /*****************************************************************************
414 * GetBits32 : returns 32 bits from the bit stream and removes them
415 *****************************************************************************/
416 #if (WORD_TYPE == uint32_t)
417 static inline uint32_t GetBits32( bit_stream_t * p_bit_stream )
421 if( p_bit_stream->fifo.i_available == 32 )
423 p_bit_stream->fifo.i_available = 0;
424 i_result = p_bit_stream->fifo.buffer;
425 p_bit_stream->fifo.buffer = 0;
429 if( p_bit_stream->p_byte <= p_bit_stream->p_end - sizeof(WORD_TYPE) )
431 if( p_bit_stream->fifo.i_available )
433 i_result = p_bit_stream->fifo.buffer;
434 p_bit_stream->fifo.buffer = WORD_AT( p_bit_stream->p_byte );
435 p_bit_stream->p_byte =
436 (byte_t *) ( ((WORD_TYPE *)p_bit_stream->p_byte) + 1 );
437 i_result |= p_bit_stream->fifo.buffer
438 >> (p_bit_stream->fifo.i_available);
439 p_bit_stream->fifo.buffer <<= (32 - p_bit_stream->fifo.i_available);
443 i_result = WORD_AT( p_bit_stream->p_byte );
444 p_bit_stream->p_byte =
445 (byte_t *) ( ((WORD_TYPE *)p_bit_stream->p_byte) + 1 );
449 p_bit_stream->fifo.i_available -= 32;
450 return UnalignedGetBits( p_bit_stream, 32 );
453 # define GetBits32( p_bit_stream ) GetBits( p_bit_stream, 32 )
456 /*****************************************************************************
457 * RealignBits : realigns the bit buffer on an 8-bit boundary
458 *****************************************************************************/
459 static inline void RealignBits( bit_stream_t * p_bit_stream )
461 p_bit_stream->fifo.buffer <<= (p_bit_stream->fifo.i_available & 0x7);
462 p_bit_stream->fifo.i_available &= ~0x7;
466 /*****************************************************************************
467 * GetChunk : reads a large chunk of data
468 *****************************************************************************
469 * The position in the stream must be byte-aligned, if unsure call
470 * RealignBits(). p_buffer must point to a buffer at least as big as i_buf_len
471 * otherwise your code will crash.
472 *****************************************************************************/
473 static inline void GetChunk( bit_stream_t * p_bit_stream,
474 byte_t * p_buffer, size_t i_buf_len )
476 ptrdiff_t i_available;
478 /* We need to take care because i_buf_len may be < 4. */
479 while( p_bit_stream->fifo.i_available > 0 && i_buf_len )
481 *p_buffer = p_bit_stream->fifo.buffer >> (8 * sizeof(WORD_TYPE) - 8);
484 p_bit_stream->fifo.buffer <<= 8;
485 p_bit_stream->fifo.i_available -= 8;
488 i_available = p_bit_stream->p_end - p_bit_stream->p_byte;
489 if( i_available >= (ptrdiff_t)i_buf_len )
491 p_bit_stream->p_decoder_fifo->p_vlc->pf_memcpy( p_buffer,
492 p_bit_stream->p_byte, i_buf_len );
493 p_bit_stream->p_byte += i_buf_len;
499 p_bit_stream->p_decoder_fifo->p_vlc->pf_memcpy( p_buffer,
500 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 );
505 if( p_bit_stream->p_decoder_fifo->b_die )
508 while( (i_available = p_bit_stream->p_end - p_bit_stream->p_byte)
509 <= (ptrdiff_t)i_buf_len );
513 p_bit_stream->p_decoder_fifo->p_vlc->pf_memcpy( p_buffer,
514 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 /*****************************************************************************
531 * Prototypes from input_dec.c
532 *****************************************************************************/
533 VLC_EXPORT( void, DecoderError, ( decoder_fifo_t * p_fifo ) );
535 #endif /* "input_ext-dec.h" */