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 1.82 2003/11/06 16:36:41 nitrox 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;
117 /*****************************************************************************
118 * bit_fifo_t : bit fifo descriptor
119 *****************************************************************************
120 * This type describes a bit fifo used to store bits while working with the
121 * input stream at the bit level.
122 *****************************************************************************/
123 typedef uint32_t WORD_TYPE;
125 typedef struct bit_fifo_t
127 /* This unsigned integer allows us to work at the bit level. This buffer
128 * can contain 32 bits, and the used space can be found on the MSb's side
129 * and the available space on the LSb's side. */
132 /* Number of bits available in the bit buffer */
137 /*****************************************************************************
138 * bit_stream_t : bit stream descriptor
139 *****************************************************************************
140 * This type, based on a PES stream, includes all the structures needed to
141 * handle the input stream like a bit stream.
142 *****************************************************************************/
153 /* The decoder fifo contains the data of the PES stream */
154 decoder_fifo_t * p_decoder_fifo;
156 /* Callback to the decoder used when changing data packets ; set
157 * to NULL if your decoder doesn't need it. */
158 void (* pf_bitstream_callback)( bit_stream_t *, vlc_bool_t );
159 /* Optional argument to the callback */
160 void * p_callback_arg;
165 mtime_t i_pts, i_dts;
166 byte_t * p_pts_validity;
171 /* Current PES packet (extracted from the PES stream) */
172 pes_packet_t * p_pes;
173 /* Current data packet (in the current PES packet) */
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 == uint32_t)
201 # define WORD_AT U32_AT
202 # define WORD_SIGNED int32_t
203 #elif (WORD_TYPE == uint64_t)
204 # define WORD_AT U64_AT
205 # define WORD_SIGNED int64_t
207 # error Unsupported WORD_TYPE
210 /*****************************************************************************
211 * Prototypes from input_ext-dec.c
212 *****************************************************************************/
213 VLC_EXPORT( void, input_ExtractPES, ( decoder_fifo_t *, pes_packet_t ** ) );
214 VLC_EXPORT( void, input_DeletePES, ( input_buffers_t *, pes_packet_t * ) );
215 VLC_EXPORT( int, InitBitstream, ( bit_stream_t *, decoder_fifo_t *, void ( * )( bit_stream_t *, vlc_bool_t ), void * p_callback_arg ) );
216 VLC_EXPORT( vlc_bool_t, NextDataPacket, ( decoder_fifo_t *, bit_stream_t * ) );
217 VLC_EXPORT( void, BitstreamNextDataPacket, ( bit_stream_t * ) );
218 VLC_EXPORT( uint32_t, UnalignedShowBits, ( bit_stream_t *, unsigned int ) );
219 VLC_EXPORT( void, UnalignedRemoveBits, ( bit_stream_t * ) );
220 VLC_EXPORT( uint32_t, UnalignedGetBits, ( bit_stream_t *, unsigned int ) );
221 VLC_EXPORT( void, CloseBitstream, ( bit_stream_t * ) );
222 VLC_EXPORT( void, CurrentPTS, ( bit_stream_t *, mtime_t *, mtime_t * ) );
223 VLC_EXPORT( void, NextPTS, ( 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 uint32_t ShowBits( bit_stream_t * p_bit_stream,
257 unsigned int i_bits )
259 if( (unsigned int)p_bit_stream->fifo.i_available >= i_bits )
261 return( p_bit_stream->fifo.buffer >> (8 * sizeof(WORD_TYPE) - i_bits) );
264 if( p_bit_stream->p_byte <= p_bit_stream->p_end - sizeof(WORD_TYPE) )
266 return( (p_bit_stream->fifo.buffer |
267 (WORD_AT( p_bit_stream->p_byte )
268 >> p_bit_stream->fifo.i_available))
269 >> (8 * sizeof(WORD_TYPE) - i_bits) );
272 return( UnalignedShowBits( p_bit_stream, i_bits ) );
275 /*****************************************************************************
276 * ShowSignedBits : return i_bits bits from the bit stream, using signed
278 *****************************************************************************/
279 static inline int32_t ShowSignedBits( bit_stream_t * p_bit_stream,
280 unsigned int i_bits )
282 if( (unsigned int)p_bit_stream->fifo.i_available >= i_bits )
284 return( (WORD_SIGNED)p_bit_stream->fifo.buffer
285 >> (8 * sizeof(WORD_TYPE) - i_bits) );
288 /* You can probably do something a little faster, but now I'm tired. */
289 return( (WORD_SIGNED)(ShowBits( p_bit_stream, i_bits ) << (32 - i_bits))
293 /*****************************************************************************
294 * RemoveBits : removes i_bits bits from the bit buffer
295 * XXX: do not use for 32 bits, see RemoveBits32
296 *****************************************************************************/
297 static inline void RemoveBits( bit_stream_t * p_bit_stream,
298 unsigned int i_bits )
300 p_bit_stream->fifo.i_available -= i_bits;
302 if( p_bit_stream->fifo.i_available >= 0 )
304 p_bit_stream->fifo.buffer <<= i_bits;
308 if( p_bit_stream->p_byte <= p_bit_stream->p_end - sizeof(WORD_TYPE) )
310 p_bit_stream->fifo.buffer = WORD_AT( p_bit_stream->p_byte )
311 << ( -p_bit_stream->fifo.i_available );
312 p_bit_stream->p_byte =
313 (byte_t *) ( ((WORD_TYPE *)p_bit_stream->p_byte) + 1 );
314 p_bit_stream->fifo.i_available += sizeof(WORD_TYPE) * 8;
318 UnalignedRemoveBits( p_bit_stream );
321 /*****************************************************************************
322 * RemoveBits32 : removes 32 bits from the bit buffer (and as a side effect,
324 *****************************************************************************/
325 #if (WORD_TYPE == uint32_t)
326 static inline void RemoveBits32( bit_stream_t * p_bit_stream )
328 if( p_bit_stream->p_byte <= p_bit_stream->p_end - sizeof(WORD_TYPE) )
330 if( p_bit_stream->fifo.i_available )
332 p_bit_stream->fifo.buffer = WORD_AT( p_bit_stream->p_byte )
333 << (32 - p_bit_stream->fifo.i_available);
334 p_bit_stream->p_byte =
335 (byte_t *) ( ((WORD_TYPE *)p_bit_stream->p_byte) + 1 );
339 p_bit_stream->p_byte =
340 (byte_t *) ( ((WORD_TYPE *)p_bit_stream->p_byte) + 1 );
344 p_bit_stream->fifo.i_available -= 32;
345 UnalignedRemoveBits( p_bit_stream );
348 # define RemoveBits32( p_bit_stream ) RemoveBits( p_bit_stream, 32 )
351 /*****************************************************************************
352 * GetBits : returns i_bits bits from the bit stream and removes them
353 * XXX: do not use for 32 bits, see GetBits32
354 *****************************************************************************/
355 static inline uint32_t GetBits( bit_stream_t * p_bit_stream,
356 unsigned int i_bits )
360 p_bit_stream->fifo.i_available -= i_bits;
362 if( p_bit_stream->fifo.i_available >= 0 )
364 i_result = p_bit_stream->fifo.buffer
365 >> (8 * sizeof(WORD_TYPE) - i_bits);
366 p_bit_stream->fifo.buffer <<= i_bits;
370 if( p_bit_stream->p_byte <= p_bit_stream->p_end - sizeof(WORD_TYPE) )
372 i_result = p_bit_stream->fifo.buffer
373 >> (8 * sizeof(WORD_TYPE) - i_bits);
374 p_bit_stream->fifo.buffer = WORD_AT( p_bit_stream->p_byte );
375 p_bit_stream->p_byte =
376 (byte_t *) ( ((WORD_TYPE *)p_bit_stream->p_byte) + 1 );
377 i_result |= p_bit_stream->fifo.buffer
378 >> (8 * sizeof(WORD_TYPE)
379 + p_bit_stream->fifo.i_available);
380 p_bit_stream->fifo.buffer <<= ( -p_bit_stream->fifo.i_available );
381 p_bit_stream->fifo.i_available += sizeof(WORD_TYPE) * 8;
385 return UnalignedGetBits( p_bit_stream, i_bits );
388 /*****************************************************************************
389 * GetSignedBits : returns i_bits bits from the bit stream and removes them,
390 * using signed arithmetic
391 * XXX: do not use for 32 bits
392 *****************************************************************************/
393 static inline int32_t GetSignedBits( bit_stream_t * p_bit_stream,
394 unsigned int i_bits )
396 if( (unsigned int)p_bit_stream->fifo.i_available >= i_bits )
400 p_bit_stream->fifo.i_available -= i_bits;
401 i_result = (WORD_SIGNED)p_bit_stream->fifo.buffer
402 >> (8 * sizeof(WORD_TYPE) - i_bits);
403 p_bit_stream->fifo.buffer <<= i_bits;
407 /* You can probably do something a little faster, but now I'm tired. */
408 return( (WORD_SIGNED)(GetBits( p_bit_stream, i_bits ) << (32 - i_bits))
412 /*****************************************************************************
413 * GetBits32 : returns 32 bits from the bit stream and removes them
414 *****************************************************************************/
415 #if (WORD_TYPE == uint32_t)
416 static inline uint32_t GetBits32( bit_stream_t * p_bit_stream )
420 if( p_bit_stream->fifo.i_available == 32 )
422 p_bit_stream->fifo.i_available = 0;
423 i_result = p_bit_stream->fifo.buffer;
424 p_bit_stream->fifo.buffer = 0;
428 if( p_bit_stream->p_byte <= p_bit_stream->p_end - sizeof(WORD_TYPE) )
430 if( p_bit_stream->fifo.i_available )
432 i_result = p_bit_stream->fifo.buffer;
433 p_bit_stream->fifo.buffer = WORD_AT( p_bit_stream->p_byte );
434 p_bit_stream->p_byte =
435 (byte_t *) ( ((WORD_TYPE *)p_bit_stream->p_byte) + 1 );
436 i_result |= p_bit_stream->fifo.buffer
437 >> (p_bit_stream->fifo.i_available);
438 p_bit_stream->fifo.buffer <<= (32 - p_bit_stream->fifo.i_available);
442 i_result = WORD_AT( p_bit_stream->p_byte );
443 p_bit_stream->p_byte =
444 (byte_t *) ( ((WORD_TYPE *)p_bit_stream->p_byte) + 1 );
448 p_bit_stream->fifo.i_available -= 32;
449 return UnalignedGetBits( p_bit_stream, 32 );
452 # define GetBits32( p_bit_stream ) GetBits( p_bit_stream, 32 )
455 /*****************************************************************************
456 * RealignBits : realigns the bit buffer on an 8-bit boundary
457 *****************************************************************************/
458 static inline void RealignBits( bit_stream_t * p_bit_stream )
460 p_bit_stream->fifo.buffer <<= (p_bit_stream->fifo.i_available & 0x7);
461 p_bit_stream->fifo.i_available &= ~0x7;
465 /*****************************************************************************
466 * GetChunk : reads a large chunk of data
467 *****************************************************************************
468 * The position in the stream must be byte-aligned, if unsure call
469 * RealignBits(). p_buffer must point to a buffer at least as big as i_buf_len
470 * otherwise your code will crash.
471 *****************************************************************************/
472 static inline void GetChunk( bit_stream_t * p_bit_stream,
473 byte_t * p_buffer, size_t i_buf_len )
475 ptrdiff_t i_available;
477 /* We need to take care because i_buf_len may be < 4. */
478 while( p_bit_stream->fifo.i_available > 0 && i_buf_len )
480 *p_buffer = p_bit_stream->fifo.buffer >> (8 * sizeof(WORD_TYPE) - 8);
483 p_bit_stream->fifo.buffer <<= 8;
484 p_bit_stream->fifo.i_available -= 8;
487 i_available = p_bit_stream->p_end - p_bit_stream->p_byte;
488 if( i_available >= (ptrdiff_t)i_buf_len )
490 p_bit_stream->p_decoder_fifo->p_vlc->pf_memcpy( p_buffer,
491 p_bit_stream->p_byte, i_buf_len );
492 p_bit_stream->p_byte += i_buf_len;
498 p_bit_stream->p_decoder_fifo->p_vlc->pf_memcpy( p_buffer,
499 p_bit_stream->p_byte, i_available );
500 p_bit_stream->p_byte = p_bit_stream->p_end;
501 p_buffer += i_available;
502 i_buf_len -= i_available;
503 BitstreamNextDataPacket( p_bit_stream );
504 if( p_bit_stream->p_decoder_fifo->b_die )
507 while( (i_available = p_bit_stream->p_end - p_bit_stream->p_byte)
508 <= (ptrdiff_t)i_buf_len );
512 p_bit_stream->p_decoder_fifo->p_vlc->pf_memcpy( p_buffer,
513 p_bit_stream->p_byte, i_buf_len );
514 p_bit_stream->p_byte += i_buf_len;
518 if( p_bit_stream->p_byte <= p_bit_stream->p_end - sizeof(WORD_TYPE) )
520 AlignWord( p_bit_stream );
526 * Communication interface between input and decoders
529 /*****************************************************************************
530 * Prototypes from input_dec.c
531 *****************************************************************************/
532 VLC_EXPORT( void, DecoderError, ( decoder_fifo_t * p_fifo ) );
534 #endif /* "input_ext-dec.h" */