[cvs] / xvidcore / src / bitstream / bitstream.h Repository:
ViewVC logotype

Annotation of /xvidcore/src/bitstream/bitstream.h

Parent Directory Parent Directory | Revision Log Revision Log


Revision 1.16.2.2 - (view) (download)

1 : edgomez 1.11 /*****************************************************************************
2 :     *
3 :     * XVID MPEG-4 VIDEO CODEC
4 :     * - Bitstream reader/writer inlined functions and constants-
5 :     *
6 : suxen_drol 1.13 * Copyright (C) 2001-2002 - Peter Ross <pross@xvid.org>
7 : edgomez 1.11 *
8 : edgomez 1.14 * This file is part of XviD, a free MPEG-4 video encoder/decoder
9 :     *
10 :     * XviD is free software; you can redistribute it and/or modify it
11 :     * 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 : edgomez 1.11 * (at your option) any later version.
14 :     *
15 :     * This program is distributed in the hope that it will be useful,
16 : edgomez 1.14 * but WITHOUT ANY WARRANTY; without even the implied warranty of
17 : edgomez 1.11 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
18 :     * GNU General Public License for more details.
19 :     *
20 :     * You should have received a copy of the GNU General Public License
21 : edgomez 1.14 * along with this program; if not, write to the Free Software
22 : edgomez 1.11 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
23 :     *
24 : edgomez 1.14 * Under section 8 of the GNU General Public License, the copyright
25 :     * holders of XVID explicitly forbid distribution in the following
26 :     * countries:
27 :     *
28 :     * - Japan
29 :     * - United States of America
30 :     *
31 :     * Linking XviD statically or dynamically with other modules is making a
32 :     * combined work based on XviD. Thus, the terms and conditions of the
33 :     * GNU General Public License cover the whole combination.
34 :     *
35 :     * As a special exception, the copyright holders of XviD give you
36 :     * permission to link XviD with independent modules that communicate with
37 :     * XviD solely through the VFW1.1 and DShow interfaces, regardless of the
38 :     * license terms of these independent modules, and to copy and distribute
39 :     * the resulting combined work under terms of your choice, provided that
40 :     * every copy of the combined work is accompanied by a complete copy of
41 :     * the source code of XviD (the version of XviD used to produce the
42 :     * combined work), being distributed under the terms of the GNU General
43 :     * Public License plus this exception. An independent module is a module
44 :     * which is not derived from or based on XviD.
45 :     *
46 :     * Note that people who make modified versions of XviD are not obligated
47 :     * to grant this special exception for their modified versions; it is
48 :     * their choice whether to do so. The GNU General Public License gives
49 :     * permission to release a modified version without this exception; this
50 :     * exception also makes it possible to release a modified version which
51 :     * carries forward this exception.
52 :     *
53 : edgomez 1.16.2.2 * $Id: bitstream.h,v 1.16.2.1 2003/04/04 22:12:07 edgomez Exp $
54 : edgomez 1.11 *
55 :     ****************************************************************************/
56 : Isibaar 1.1
57 :     #ifndef _BITSTREAM_H_
58 :     #define _BITSTREAM_H_
59 :    
60 : edgomez 1.16.2.1 #include <stdio.h>
61 :    
62 : Isibaar 1.1 #include "../portab.h"
63 :     #include "../decoder.h"
64 :     #include "../encoder.h"
65 :    
66 : edgomez 1.11
67 :     /*****************************************************************************
68 :     * Constants
69 :     ****************************************************************************/
70 :    
71 : edgomez 1.15 /* comment any #defs we dont use */
72 : Isibaar 1.1
73 :     #define VIDOBJ_START_CODE 0x00000100 /* ..0x0000011f */
74 :     #define VIDOBJLAY_START_CODE 0x00000120 /* ..0x0000012f */
75 :     #define VISOBJSEQ_START_CODE 0x000001b0
76 :     #define VISOBJSEQ_STOP_CODE 0x000001b1 /* ??? */
77 :     #define USERDATA_START_CODE 0x000001b2
78 :     #define GRPOFVOP_START_CODE 0x000001b3
79 : edgomez 1.15 /*#define VIDSESERR_ERROR_CODE 0x000001b4 */
80 : Isibaar 1.1 #define VISOBJ_START_CODE 0x000001b5
81 : edgomez 1.15 /*#define SLICE_START_CODE 0x000001b7 */
82 :     /*#define EXT_START_CODE 0x000001b8 */
83 : Isibaar 1.1
84 :    
85 :     #define VISOBJ_TYPE_VIDEO 1
86 : edgomez 1.15 /*#define VISOBJ_TYPE_STILLTEXTURE 2 */
87 :     /*#define VISOBJ_TYPE_MESH 3 */
88 :     /*#define VISOBJ_TYPE_FBA 4 */
89 :     /*#define VISOBJ_TYPE_3DMESH 5 */
90 : Isibaar 1.1
91 :    
92 :     #define VIDOBJLAY_TYPE_SIMPLE 1
93 : edgomez 1.15 /*#define VIDOBJLAY_TYPE_SIMPLE_SCALABLE 2 */
94 : Isibaar 1.1 #define VIDOBJLAY_TYPE_CORE 3
95 :     #define VIDOBJLAY_TYPE_MAIN 4
96 :    
97 :    
98 : edgomez 1.15 /*#define VIDOBJLAY_AR_SQUARE 1 */
99 :     /*#define VIDOBJLAY_AR_625TYPE_43 2 */
100 :     /*#define VIDOBJLAY_AR_525TYPE_43 3 */
101 :     /*#define VIDOBJLAY_AR_625TYPE_169 8 */
102 :     /*#define VIDOBJLAY_AR_525TYPE_169 9 */
103 : Isibaar 1.1 #define VIDOBJLAY_AR_EXTPAR 15
104 :    
105 :    
106 :     #define VIDOBJLAY_SHAPE_RECTANGULAR 0
107 :     #define VIDOBJLAY_SHAPE_BINARY 1
108 :     #define VIDOBJLAY_SHAPE_BINARY_ONLY 2
109 :     #define VIDOBJLAY_SHAPE_GRAYSCALE 3
110 :    
111 :     #define VO_START_CODE 0x8
112 :     #define VOL_START_CODE 0x12
113 :     #define VOP_START_CODE 0x1b6
114 :    
115 :     #define READ_MARKER() BitstreamSkip(bs, 1)
116 :     #define WRITE_MARKER() BitstreamPutBit(bs, 1)
117 :    
118 : edgomez 1.15 /* vop coding types */
119 :     /* intra, prediction, backward, sprite, not_coded */
120 : Isibaar 1.1 #define I_VOP 0
121 :     #define P_VOP 1
122 :     #define B_VOP 2
123 :     #define S_VOP 3
124 :     #define N_VOP 4
125 :    
126 : edgomez 1.15 /* resync-specific */
127 : suxen_drol 1.9 #define NUMBITS_VP_RESYNC_MARKER 17
128 :     #define RESYNC_MARKER 1
129 :    
130 :    
131 : edgomez 1.11 /*****************************************************************************
132 :     * Prototypes
133 :     ****************************************************************************/
134 :    
135 : suxen_drol 1.9 int
136 : suxen_drol 1.10 read_video_packet_header(Bitstream *bs, const int addbits, int * quant);
137 : suxen_drol 1.9
138 : Isibaar 1.1
139 : edgomez 1.15 /* header stuff */
140 : edgomez 1.6 int BitstreamReadHeaders(Bitstream * bs,
141 :     DECODER * dec,
142 :     uint32_t * rounding,
143 :     uint32_t * quant,
144 :     uint32_t * fcode_forward,
145 :     uint32_t * fcode_backward,
146 :     uint32_t * intra_dc_threshold);
147 : Isibaar 1.1
148 :    
149 :     void BitstreamWriteVolHeader(Bitstream * const bs,
150 : edgomez 1.6 const MBParam * pParam,
151 :     const FRAMEINFO * frame);
152 : Isibaar 1.1
153 :     void BitstreamWriteVopHeader(Bitstream * const bs,
154 : edgomez 1.6 const MBParam * pParam,
155 : suxen_drol 1.8 const FRAMEINFO * frame,
156 :     int vop_coded);
157 : Isibaar 1.1
158 : edgomez 1.11 /*****************************************************************************
159 :     * Inlined functions
160 :     ****************************************************************************/
161 :    
162 : Isibaar 1.1 /* initialise bitstream structure */
163 :    
164 : edgomez 1.6 static void __inline
165 :     BitstreamInit(Bitstream * const bs,
166 :     void *const bitstream,
167 :     uint32_t length)
168 : Isibaar 1.1 {
169 :     uint32_t tmp;
170 : edgomez 1.16.2.1 size_t bitpos;
171 :     ptr_t adjbitstream = (ptr_t)bitstream;
172 : Isibaar 1.1
173 : edgomez 1.16.2.1 /*
174 :     * Start the stream on a uint32_t boundary, by rounding down to the
175 :     * previous uint32_t and skipping the intervening bytes.
176 :     */
177 :     bitpos = ((sizeof(uint32_t)-1) & (size_t)bitstream);
178 :     adjbitstream = adjbitstream - bitpos;
179 :     bs->start = bs->tail = (uint32_t *) adjbitstream;
180 : Isibaar 1.1
181 : edgomez 1.16.2.1 tmp = *bs->start;
182 : Isibaar 1.1 #ifndef ARCH_IS_BIG_ENDIAN
183 :     BSWAP(tmp);
184 :     #endif
185 :     bs->bufa = tmp;
186 :    
187 : edgomez 1.16.2.1 tmp = *(bs->start + 1);
188 : Isibaar 1.1 #ifndef ARCH_IS_BIG_ENDIAN
189 :     BSWAP(tmp);
190 :     #endif
191 :     bs->bufb = tmp;
192 :    
193 :     bs->buf = 0;
194 : edgomez 1.16.2.1 bs->pos = bs->initpos = bitpos*8;
195 : Isibaar 1.1 bs->length = length;
196 :     }
197 :    
198 :    
199 :     /* reset bitstream state */
200 :    
201 : edgomez 1.6 static void __inline
202 :     BitstreamReset(Bitstream * const bs)
203 : Isibaar 1.1 {
204 :     uint32_t tmp;
205 :    
206 :     bs->tail = bs->start;
207 :    
208 :     tmp = *bs->start;
209 :     #ifndef ARCH_IS_BIG_ENDIAN
210 :     BSWAP(tmp);
211 :     #endif
212 :     bs->bufa = tmp;
213 :    
214 :     tmp = *(bs->start + 1);
215 :     #ifndef ARCH_IS_BIG_ENDIAN
216 :     BSWAP(tmp);
217 :     #endif
218 :     bs->bufb = tmp;
219 :    
220 :     bs->buf = 0;
221 : edgomez 1.16.2.1 bs->pos = bs->initpos;
222 : Isibaar 1.1 }
223 :    
224 :    
225 :     /* reads n bits from bitstream without changing the stream pos */
226 :    
227 : edgomez 1.6 static uint32_t __inline
228 :     BitstreamShowBits(Bitstream * const bs,
229 :     const uint32_t bits)
230 : Isibaar 1.1 {
231 :     int nbit = (bits + bs->pos) - 32;
232 : edgomez 1.6
233 :     if (nbit > 0) {
234 :     return ((bs->bufa & (0xffffffff >> bs->pos)) << nbit) | (bs->
235 :     bufb >> (32 -
236 :     nbit));
237 :     } else {
238 : Isibaar 1.1 return (bs->bufa & (0xffffffff >> bs->pos)) >> (32 - bs->pos - bits);
239 :     }
240 :     }
241 :    
242 :    
243 :     /* skip n bits forward in bitstream */
244 :    
245 : edgomez 1.11 static void __inline
246 : edgomez 1.6 BitstreamSkip(Bitstream * const bs,
247 :     const uint32_t bits)
248 : Isibaar 1.1 {
249 :     bs->pos += bits;
250 :    
251 : edgomez 1.6 if (bs->pos >= 32) {
252 : Isibaar 1.1 uint32_t tmp;
253 :    
254 :     bs->bufa = bs->bufb;
255 : edgomez 1.6 tmp = *((uint32_t *) bs->tail + 2);
256 : Isibaar 1.1 #ifndef ARCH_IS_BIG_ENDIAN
257 :     BSWAP(tmp);
258 :     #endif
259 :     bs->bufb = tmp;
260 :     bs->tail++;
261 :     bs->pos -= 32;
262 :     }
263 :     }
264 : suxen_drol 1.9
265 :    
266 : edgomez 1.15 /* number of bits to next byte alignment */
267 : edgomez 1.11 static uint32_t __inline
268 : suxen_drol 1.9 BitstreamNumBitsToByteAlign(Bitstream *bs)
269 :     {
270 :     uint32_t n = (32 - bs->pos) % 8;
271 :     return n == 0 ? 8 : n;
272 :     }
273 :    
274 :    
275 : edgomez 1.15 /* show nbits from next byte alignment */
276 : edgomez 1.11 static uint32_t __inline
277 : suxen_drol 1.9 BitstreamShowBitsFromByteAlign(Bitstream *bs, int bits)
278 :     {
279 :     int bspos = bs->pos + BitstreamNumBitsToByteAlign(bs);
280 :     int nbit = (bits + bspos) - 32;
281 :    
282 :     if (bspos >= 32) {
283 :     return bs->bufb >> (32 - nbit);
284 :     } else if (nbit > 0) {
285 :     return ((bs->bufa & (0xffffffff >> bspos)) << nbit) | (bs->
286 :     bufb >> (32 -
287 :     nbit));
288 :     } else {
289 :     return (bs->bufa & (0xffffffff >> bspos)) >> (32 - bspos - bits);
290 :     }
291 :    
292 :     }
293 :    
294 : Isibaar 1.1
295 :    
296 :     /* move forward to the next byte boundary */
297 :    
298 : edgomez 1.11 static void __inline
299 : edgomez 1.6 BitstreamByteAlign(Bitstream * const bs)
300 : Isibaar 1.1 {
301 :     uint32_t remainder = bs->pos % 8;
302 : edgomez 1.6
303 :     if (remainder) {
304 : Isibaar 1.1 BitstreamSkip(bs, 8 - remainder);
305 :     }
306 :     }
307 :    
308 :    
309 :     /* bitstream length (unit bits) */
310 :    
311 : edgomez 1.6 static uint32_t __inline
312 :     BitstreamPos(const Bitstream * const bs)
313 : Isibaar 1.1 {
314 : edgomez 1.16.2.1 return((uint32_t)(8*((ptr_t)bs->tail - (ptr_t)bs->start) + bs->pos - bs->initpos));
315 : Isibaar 1.1 }
316 :    
317 :    
318 :     /* flush the bitstream & return length (unit bytes)
319 :     NOTE: assumes no futher bitstream functions will be called.
320 :     */
321 :    
322 : edgomez 1.6 static uint32_t __inline
323 :     BitstreamLength(Bitstream * const bs)
324 : Isibaar 1.1 {
325 : edgomez 1.16 uint32_t len = (uint32_t)((ptr_t)bs->tail - (ptr_t)bs->start);
326 : Isibaar 1.1
327 : edgomez 1.6 if (bs->pos) {
328 : Isibaar 1.1 uint32_t b = bs->buf;
329 : edgomez 1.6
330 : Isibaar 1.1 #ifndef ARCH_IS_BIG_ENDIAN
331 :     BSWAP(b);
332 :     #endif
333 :     *bs->tail = b;
334 :    
335 :     len += (bs->pos + 7) / 8;
336 : edgomez 1.6 }
337 : edgomez 1.16.2.1
338 :     /* initpos is always on a byte boundary */
339 :     if (bs->initpos)
340 :     len -= bs->initpos/8;
341 : Isibaar 1.1
342 :     return len;
343 :     }
344 :    
345 :    
346 :     /* move bitstream position forward by n bits and write out buffer if needed */
347 :    
348 : edgomez 1.6 static void __inline
349 :     BitstreamForward(Bitstream * const bs,
350 :     const uint32_t bits)
351 : Isibaar 1.1 {
352 : edgomez 1.6 bs->pos += bits;
353 : Isibaar 1.1
354 : edgomez 1.6 if (bs->pos >= 32) {
355 : Isibaar 1.1 uint32_t b = bs->buf;
356 : edgomez 1.6
357 : Isibaar 1.1 #ifndef ARCH_IS_BIG_ENDIAN
358 :     BSWAP(b);
359 :     #endif
360 :     *bs->tail++ = b;
361 :     bs->buf = 0;
362 :     bs->pos -= 32;
363 : edgomez 1.6 }
364 : Isibaar 1.1 }
365 :    
366 :     /* read n bits from bitstream */
367 :    
368 : edgomez 1.6 static uint32_t __inline
369 :     BitstreamGetBits(Bitstream * const bs,
370 :     const uint32_t n)
371 : Isibaar 1.1 {
372 :     uint32_t ret = BitstreamShowBits(bs, n);
373 : edgomez 1.6
374 : Isibaar 1.1 BitstreamSkip(bs, n);
375 :     return ret;
376 :     }
377 :    
378 :    
379 :     /* read single bit from bitstream */
380 :    
381 : edgomez 1.6 static uint32_t __inline
382 :     BitstreamGetBit(Bitstream * const bs)
383 : Isibaar 1.1 {
384 :     return BitstreamGetBits(bs, 1);
385 :     }
386 :    
387 :    
388 :     /* write single bit to bitstream */
389 :    
390 : edgomez 1.6 static void __inline
391 :     BitstreamPutBit(Bitstream * const bs,
392 :     const uint32_t bit)
393 : Isibaar 1.1 {
394 : edgomez 1.6 if (bit)
395 : Isibaar 1.1 bs->buf |= (0x80000000 >> bs->pos);
396 :    
397 : edgomez 1.6 BitstreamForward(bs, 1);
398 : Isibaar 1.1 }
399 :    
400 :    
401 :     /* write n bits to bitstream */
402 :    
403 : edgomez 1.6 static void __inline
404 :     BitstreamPutBits(Bitstream * const bs,
405 :     const uint32_t value,
406 :     const uint32_t size)
407 : Isibaar 1.1 {
408 :     uint32_t shift = 32 - bs->pos - size;
409 :    
410 :     if (shift <= 32) {
411 :     bs->buf |= value << shift;
412 :     BitstreamForward(bs, size);
413 :     } else {
414 :     uint32_t remainder;
415 :    
416 :     shift = size - (32 - bs->pos);
417 :     bs->buf |= value >> shift;
418 :     BitstreamForward(bs, size - shift);
419 :     remainder = shift;
420 :    
421 :     shift = 32 - shift;
422 : edgomez 1.6
423 : Isibaar 1.1 bs->buf |= value << shift;
424 :     BitstreamForward(bs, remainder);
425 :     }
426 : edgomez 1.16.2.2 }
427 :    
428 :     static const int stuffing_codes[8] =
429 :     {
430 :     /* nbits stuffing code */
431 :     0, /* 1 0 */
432 :     1, /* 2 01 */
433 :     3, /* 3 011 */
434 :     7, /* 4 0111 */
435 :     0xf, /* 5 01111 */
436 :     0x1f, /* 6 011111 */
437 :     0x3f, /* 7 0111111 */
438 :     0x7f, /* 8 01111111 */
439 :     };
440 :    
441 :     /* pad bitstream to the next byte boundary */
442 :    
443 :     static void __inline
444 :     BitstreamPad(Bitstream * const bs)
445 :     {
446 :     int bits = 8 - (bs->pos % 8);
447 :     if (bits < 8)
448 :     BitstreamPutBits(bs, stuffing_codes[bits - 1], bits);
449 :     }
450 :    
451 :     /*
452 :     * pad bitstream to the next byte boundary
453 :     * alway pad: even if currently at the byte boundary
454 :     */
455 :    
456 :     static void __inline
457 :     BitstreamPadAlways(Bitstream * const bs)
458 :     {
459 :     int bits = 8 - (bs->pos % 8);
460 :     BitstreamPutBits(bs, stuffing_codes[bits - 1], bits);
461 : Isibaar 1.1 }
462 :    
463 : edgomez 1.11 #endif /* _BITSTREAM_H_ */

No admin address has been configured
ViewVC Help
Powered by ViewVC 1.0.4