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caa336b4 MN |
1 | /** |
2 | * @file bitstream.h | |
3 | * bitstream api header. | |
4 | */ | |
5 | ||
6 | #ifndef BITSTREAM_H | |
7 | #define BITSTREAM_H | |
8 | ||
9 | //#define ALT_BITSTREAM_WRITER | |
10 | //#define ALIGNED_BITSTREAM_WRITER | |
11 | ||
12 | #define ALT_BITSTREAM_READER | |
13 | //#define LIBMPEG2_BITSTREAM_READER | |
14 | //#define A32_BITSTREAM_READER | |
15 | #define LIBMPEG2_BITSTREAM_READER_HACK //add BERO | |
16 | ||
17 | #if defined(ARCH_X86) || defined(ARCH_X86_64) | |
18 | // avoid +32 for shift optimization (gcc should do that ...) | |
19 | static inline int32_t NEG_SSR32( int32_t a, int8_t s){ | |
20 | asm ("sarl %1, %0\n\t" | |
21 | : "+r" (a) | |
22 | : "ic" ((uint8_t)(-s)) | |
23 | ); | |
24 | return a; | |
25 | } | |
26 | static inline uint32_t NEG_USR32(uint32_t a, int8_t s){ | |
27 | asm ("shrl %1, %0\n\t" | |
28 | : "+r" (a) | |
29 | : "ic" ((uint8_t)(-s)) | |
30 | ); | |
31 | return a; | |
32 | } | |
33 | #else | |
34 | # define NEG_SSR32(a,s) ((( int32_t)(a))>>(32-(s))) | |
35 | # define NEG_USR32(a,s) (((uint32_t)(a))>>(32-(s))) | |
36 | #endif | |
37 | ||
38 | /* bit output */ | |
39 | ||
40 | /* buf and buf_end must be present and used by every alternative writer. */ | |
41 | typedef struct PutBitContext { | |
42 | #ifdef ALT_BITSTREAM_WRITER | |
43 | uint8_t *buf, *buf_end; | |
44 | int index; | |
45 | #else | |
46 | uint32_t bit_buf; | |
47 | int bit_left; | |
48 | uint8_t *buf, *buf_ptr, *buf_end; | |
49 | #endif | |
50 | } PutBitContext; | |
51 | ||
52 | static inline void init_put_bits(PutBitContext *s, uint8_t *buffer, int buffer_size) | |
53 | { | |
54 | s->buf = buffer; | |
55 | s->buf_end = s->buf + buffer_size; | |
56 | #ifdef ALT_BITSTREAM_WRITER | |
57 | s->index=0; | |
58 | ((uint32_t*)(s->buf))[0]=0; | |
59 | // memset(buffer, 0, buffer_size); | |
60 | #else | |
61 | s->buf_ptr = s->buf; | |
62 | s->bit_left=32; | |
63 | s->bit_buf=0; | |
64 | #endif | |
65 | } | |
66 | ||
67 | /* return the number of bits output */ | |
68 | static inline int put_bits_count(PutBitContext *s) | |
69 | { | |
70 | #ifdef ALT_BITSTREAM_WRITER | |
71 | return s->index; | |
72 | #else | |
73 | return (s->buf_ptr - s->buf) * 8 + 32 - s->bit_left; | |
74 | #endif | |
75 | } | |
76 | ||
77 | /* pad the end of the output stream with zeros */ | |
78 | static inline void flush_put_bits(PutBitContext *s) | |
79 | { | |
80 | #ifdef ALT_BITSTREAM_WRITER | |
81 | align_put_bits(s); | |
82 | #else | |
83 | s->bit_buf<<= s->bit_left; | |
84 | while (s->bit_left < 32) { | |
85 | /* XXX: should test end of buffer */ | |
86 | *s->buf_ptr++=s->bit_buf >> 24; | |
87 | s->bit_buf<<=8; | |
88 | s->bit_left+=8; | |
89 | } | |
90 | s->bit_left=32; | |
91 | s->bit_buf=0; | |
92 | #endif | |
93 | } | |
94 | ||
95 | void align_put_bits(PutBitContext *s); | |
96 | void put_string(PutBitContext * pbc, char *s, int put_zero); | |
97 | ||
98 | /* bit input */ | |
99 | /* buffer, buffer_end and size_in_bits must be present and used by every reader */ | |
100 | typedef struct GetBitContext { | |
101 | const uint8_t *buffer, *buffer_end; | |
102 | #ifdef ALT_BITSTREAM_READER | |
103 | int index; | |
104 | #elif defined LIBMPEG2_BITSTREAM_READER | |
105 | uint8_t *buffer_ptr; | |
106 | uint32_t cache; | |
107 | int bit_count; | |
108 | #elif defined A32_BITSTREAM_READER | |
109 | uint32_t *buffer_ptr; | |
110 | uint32_t cache0; | |
111 | uint32_t cache1; | |
112 | int bit_count; | |
113 | #endif | |
114 | int size_in_bits; | |
115 | } GetBitContext; | |
116 | ||
117 | #define VLC_TYPE int16_t | |
118 | ||
119 | typedef struct VLC { | |
120 | int bits; | |
121 | VLC_TYPE (*table)[2]; ///< code, bits | |
122 | int table_size, table_allocated; | |
123 | } VLC; | |
124 | ||
125 | typedef struct RL_VLC_ELEM { | |
126 | int16_t level; | |
127 | int8_t len; | |
128 | uint8_t run; | |
129 | } RL_VLC_ELEM; | |
130 | ||
131 | #ifdef ARCH_SPARC | |
132 | #define UNALIGNED_STORES_ARE_BAD | |
133 | #endif | |
134 | ||
135 | /* used to avoid missaligned exceptions on some archs (alpha, ...) */ | |
136 | #if defined(ARCH_X86) || defined(ARCH_X86_64) | |
137 | # define unaligned32(a) (*(const uint32_t*)(a)) | |
138 | #else | |
139 | # ifdef __GNUC__ | |
140 | static inline uint32_t unaligned32(const void *v) { | |
141 | struct Unaligned { | |
142 | uint32_t i; | |
143 | } __attribute__((packed)); | |
144 | ||
145 | return ((const struct Unaligned *) v)->i; | |
146 | } | |
147 | # elif defined(__DECC) | |
148 | static inline uint32_t unaligned32(const void *v) { | |
149 | return *(const __unaligned uint32_t *) v; | |
150 | } | |
151 | # else | |
152 | static inline uint32_t unaligned32(const void *v) { | |
153 | return *(const uint32_t *) v; | |
154 | } | |
155 | # endif | |
156 | #endif //!ARCH_X86 | |
157 | ||
158 | #ifndef ALT_BITSTREAM_WRITER | |
159 | static inline void put_bits(PutBitContext *s, int n, unsigned int value) | |
160 | { | |
161 | unsigned int bit_buf; | |
162 | int bit_left; | |
163 | ||
164 | #ifdef STATS | |
165 | st_out_bit_counts[st_current_index] += n; | |
166 | #endif | |
167 | // printf("put_bits=%d %x\n", n, value); | |
168 | assert(n == 32 || value < (1U << n)); | |
169 | ||
170 | bit_buf = s->bit_buf; | |
171 | bit_left = s->bit_left; | |
172 | ||
173 | // printf("n=%d value=%x cnt=%d buf=%x\n", n, value, bit_cnt, bit_buf); | |
174 | /* XXX: optimize */ | |
175 | if (n < bit_left) { | |
176 | bit_buf = (bit_buf<<n) | value; | |
177 | bit_left-=n; | |
178 | } else { | |
179 | bit_buf<<=bit_left; | |
180 | bit_buf |= value >> (n - bit_left); | |
181 | #ifdef UNALIGNED_STORES_ARE_BAD | |
182 | if (3 & (intptr_t) s->buf_ptr) { | |
183 | s->buf_ptr[0] = bit_buf >> 24; | |
184 | s->buf_ptr[1] = bit_buf >> 16; | |
185 | s->buf_ptr[2] = bit_buf >> 8; | |
186 | s->buf_ptr[3] = bit_buf ; | |
187 | } else | |
188 | #endif | |
189 | *(uint32_t *)s->buf_ptr = be2me_32(bit_buf); | |
190 | //printf("bitbuf = %08x\n", bit_buf); | |
191 | s->buf_ptr+=4; | |
192 | bit_left+=32 - n; | |
193 | bit_buf = value; | |
194 | } | |
195 | ||
196 | s->bit_buf = bit_buf; | |
197 | s->bit_left = bit_left; | |
198 | } | |
199 | #endif | |
200 | ||
201 | ||
202 | #ifdef ALT_BITSTREAM_WRITER | |
203 | static inline void put_bits(PutBitContext *s, int n, unsigned int value) | |
204 | { | |
205 | # ifdef ALIGNED_BITSTREAM_WRITER | |
206 | # if defined(ARCH_X86) || defined(ARCH_X86_64) | |
207 | asm volatile( | |
208 | "movl %0, %%ecx \n\t" | |
209 | "xorl %%eax, %%eax \n\t" | |
210 | "shrdl %%cl, %1, %%eax \n\t" | |
211 | "shrl %%cl, %1 \n\t" | |
212 | "movl %0, %%ecx \n\t" | |
213 | "shrl $3, %%ecx \n\t" | |
214 | "andl $0xFFFFFFFC, %%ecx \n\t" | |
215 | "bswapl %1 \n\t" | |
216 | "orl %1, (%2, %%ecx) \n\t" | |
217 | "bswapl %%eax \n\t" | |
218 | "addl %3, %0 \n\t" | |
219 | "movl %%eax, 4(%2, %%ecx) \n\t" | |
220 | : "=&r" (s->index), "=&r" (value) | |
221 | : "r" (s->buf), "r" (n), "0" (s->index), "1" (value<<(-n)) | |
222 | : "%eax", "%ecx" | |
223 | ); | |
224 | # else | |
225 | int index= s->index; | |
226 | uint32_t *ptr= ((uint32_t *)s->buf)+(index>>5); | |
227 | ||
228 | value<<= 32-n; | |
229 | ||
230 | ptr[0] |= be2me_32(value>>(index&31)); | |
231 | ptr[1] = be2me_32(value<<(32-(index&31))); | |
232 | //if(n>24) printf("%d %d\n", n, value); | |
233 | index+= n; | |
234 | s->index= index; | |
235 | # endif | |
236 | # else //ALIGNED_BITSTREAM_WRITER | |
237 | # if defined(ARCH_X86) || defined(ARCH_X86_64) | |
238 | asm volatile( | |
239 | "movl $7, %%ecx \n\t" | |
240 | "andl %0, %%ecx \n\t" | |
241 | "addl %3, %%ecx \n\t" | |
242 | "negl %%ecx \n\t" | |
243 | "shll %%cl, %1 \n\t" | |
244 | "bswapl %1 \n\t" | |
245 | "movl %0, %%ecx \n\t" | |
246 | "shrl $3, %%ecx \n\t" | |
247 | "orl %1, (%%ecx, %2) \n\t" | |
248 | "addl %3, %0 \n\t" | |
249 | "movl $0, 4(%%ecx, %2) \n\t" | |
250 | : "=&r" (s->index), "=&r" (value) | |
251 | : "r" (s->buf), "r" (n), "0" (s->index), "1" (value) | |
252 | : "%ecx" | |
253 | ); | |
254 | # else | |
255 | int index= s->index; | |
256 | uint32_t *ptr= (uint32_t*)(((uint8_t *)s->buf)+(index>>3)); | |
257 | ||
258 | ptr[0] |= be2me_32(value<<(32-n-(index&7) )); | |
259 | ptr[1] = 0; | |
260 | //if(n>24) printf("%d %d\n", n, value); | |
261 | index+= n; | |
262 | s->index= index; | |
263 | # endif | |
264 | # endif //!ALIGNED_BITSTREAM_WRITER | |
265 | } | |
266 | #endif | |
267 | ||
268 | ||
269 | static inline uint8_t* pbBufPtr(PutBitContext *s) | |
270 | { | |
271 | #ifdef ALT_BITSTREAM_WRITER | |
272 | return s->buf + (s->index>>3); | |
273 | #else | |
274 | return s->buf_ptr; | |
275 | #endif | |
276 | } | |
277 | ||
278 | /** | |
279 | * | |
280 | * PutBitContext must be flushed & aligned to a byte boundary before calling this. | |
281 | */ | |
282 | static inline void skip_put_bytes(PutBitContext *s, int n){ | |
283 | assert((put_bits_count(s)&7)==0); | |
284 | #ifdef ALT_BITSTREAM_WRITER | |
285 | FIXME may need some cleaning of the buffer | |
286 | s->index += n<<3; | |
287 | #else | |
288 | assert(s->bit_left==32); | |
289 | s->buf_ptr += n; | |
290 | #endif | |
291 | } | |
292 | ||
293 | /** | |
294 | * Changes the end of the buffer. | |
295 | */ | |
296 | static inline void set_put_bits_buffer_size(PutBitContext *s, int size){ | |
297 | s->buf_end= s->buf + size; | |
298 | } | |
299 | ||
300 | /* Bitstream reader API docs: | |
301 | name | |
302 | abritary name which is used as prefix for the internal variables | |
303 | ||
304 | gb | |
305 | getbitcontext | |
306 | ||
307 | OPEN_READER(name, gb) | |
308 | loads gb into local variables | |
309 | ||
310 | CLOSE_READER(name, gb) | |
311 | stores local vars in gb | |
312 | ||
313 | UPDATE_CACHE(name, gb) | |
314 | refills the internal cache from the bitstream | |
315 | after this call at least MIN_CACHE_BITS will be available, | |
316 | ||
317 | GET_CACHE(name, gb) | |
318 | will output the contents of the internal cache, next bit is MSB of 32 or 64 bit (FIXME 64bit) | |
319 | ||
320 | SHOW_UBITS(name, gb, num) | |
321 | will return the nest num bits | |
322 | ||
323 | SHOW_SBITS(name, gb, num) | |
324 | will return the nest num bits and do sign extension | |
325 | ||
326 | SKIP_BITS(name, gb, num) | |
327 | will skip over the next num bits | |
328 | note, this is equinvalent to SKIP_CACHE; SKIP_COUNTER | |
329 | ||
330 | SKIP_CACHE(name, gb, num) | |
331 | will remove the next num bits from the cache (note SKIP_COUNTER MUST be called before UPDATE_CACHE / CLOSE_READER) | |
332 | ||
333 | SKIP_COUNTER(name, gb, num) | |
334 | will increment the internal bit counter (see SKIP_CACHE & SKIP_BITS) | |
335 | ||
336 | LAST_SKIP_CACHE(name, gb, num) | |
337 | will remove the next num bits from the cache if it is needed for UPDATE_CACHE otherwise it will do nothing | |
338 | ||
339 | LAST_SKIP_BITS(name, gb, num) | |
340 | is equinvalent to SKIP_LAST_CACHE; SKIP_COUNTER | |
341 | ||
342 | for examples see get_bits, show_bits, skip_bits, get_vlc | |
343 | */ | |
344 | ||
345 | static inline int unaligned32_be(const void *v) | |
346 | { | |
347 | #ifdef CONFIG_ALIGN | |
348 | const uint8_t *p=v; | |
349 | return (((p[0]<<8) | p[1])<<16) | (p[2]<<8) | (p[3]); | |
350 | #else | |
351 | return be2me_32( unaligned32(v)); //original | |
352 | #endif | |
353 | } | |
354 | ||
355 | #ifdef ALT_BITSTREAM_READER | |
356 | # define MIN_CACHE_BITS 25 | |
357 | ||
358 | # define OPEN_READER(name, gb)\ | |
359 | int name##_index= (gb)->index;\ | |
360 | int name##_cache= 0;\ | |
361 | ||
362 | # define CLOSE_READER(name, gb)\ | |
363 | (gb)->index= name##_index;\ | |
364 | ||
365 | # define UPDATE_CACHE(name, gb)\ | |
366 | name##_cache= unaligned32_be( ((const uint8_t *)(gb)->buffer)+(name##_index>>3) ) << (name##_index&0x07);\ | |
367 | ||
368 | # define SKIP_CACHE(name, gb, num)\ | |
369 | name##_cache <<= (num);\ | |
370 | ||
371 | // FIXME name? | |
372 | # define SKIP_COUNTER(name, gb, num)\ | |
373 | name##_index += (num);\ | |
374 | ||
375 | # define SKIP_BITS(name, gb, num)\ | |
376 | {\ | |
377 | SKIP_CACHE(name, gb, num)\ | |
378 | SKIP_COUNTER(name, gb, num)\ | |
379 | }\ | |
380 | ||
381 | # define LAST_SKIP_BITS(name, gb, num) SKIP_COUNTER(name, gb, num) | |
382 | # define LAST_SKIP_CACHE(name, gb, num) ; | |
383 | ||
384 | # define SHOW_UBITS(name, gb, num)\ | |
385 | NEG_USR32(name##_cache, num) | |
386 | ||
387 | # define SHOW_SBITS(name, gb, num)\ | |
388 | NEG_SSR32(name##_cache, num) | |
389 | ||
390 | # define GET_CACHE(name, gb)\ | |
391 | ((uint32_t)name##_cache) | |
392 | ||
393 | static inline int get_bits_count(GetBitContext *s){ | |
394 | return s->index; | |
395 | } | |
396 | #elif defined LIBMPEG2_BITSTREAM_READER | |
397 | //libmpeg2 like reader | |
398 | ||
399 | # define MIN_CACHE_BITS 17 | |
400 | ||
401 | # define OPEN_READER(name, gb)\ | |
402 | int name##_bit_count=(gb)->bit_count;\ | |
403 | int name##_cache= (gb)->cache;\ | |
404 | uint8_t * name##_buffer_ptr=(gb)->buffer_ptr;\ | |
405 | ||
406 | # define CLOSE_READER(name, gb)\ | |
407 | (gb)->bit_count= name##_bit_count;\ | |
408 | (gb)->cache= name##_cache;\ | |
409 | (gb)->buffer_ptr= name##_buffer_ptr;\ | |
410 | ||
411 | #ifdef LIBMPEG2_BITSTREAM_READER_HACK | |
412 | ||
413 | # define UPDATE_CACHE(name, gb)\ | |
414 | if(name##_bit_count >= 0){\ | |
415 | name##_cache+= (int)be2me_16(*(uint16_t*)name##_buffer_ptr) << name##_bit_count;\ | |
416 | ((uint16_t*)name##_buffer_ptr)++;\ | |
417 | name##_bit_count-= 16;\ | |
418 | }\ | |
419 | ||
420 | #else | |
421 | ||
422 | # define UPDATE_CACHE(name, gb)\ | |
423 | if(name##_bit_count >= 0){\ | |
424 | name##_cache+= ((name##_buffer_ptr[0]<<8) + name##_buffer_ptr[1]) << name##_bit_count;\ | |
425 | name##_buffer_ptr+=2;\ | |
426 | name##_bit_count-= 16;\ | |
427 | }\ | |
428 | ||
429 | #endif | |
430 | ||
431 | # define SKIP_CACHE(name, gb, num)\ | |
432 | name##_cache <<= (num);\ | |
433 | ||
434 | # define SKIP_COUNTER(name, gb, num)\ | |
435 | name##_bit_count += (num);\ | |
436 | ||
437 | # define SKIP_BITS(name, gb, num)\ | |
438 | {\ | |
439 | SKIP_CACHE(name, gb, num)\ | |
440 | SKIP_COUNTER(name, gb, num)\ | |
441 | }\ | |
442 | ||
443 | # define LAST_SKIP_BITS(name, gb, num) SKIP_BITS(name, gb, num) | |
444 | # define LAST_SKIP_CACHE(name, gb, num) SKIP_CACHE(name, gb, num) | |
445 | ||
446 | # define SHOW_UBITS(name, gb, num)\ | |
447 | NEG_USR32(name##_cache, num) | |
448 | ||
449 | # define SHOW_SBITS(name, gb, num)\ | |
450 | NEG_SSR32(name##_cache, num) | |
451 | ||
452 | # define GET_CACHE(name, gb)\ | |
453 | ((uint32_t)name##_cache) | |
454 | ||
455 | static inline int get_bits_count(GetBitContext *s){ | |
456 | return (s->buffer_ptr - s->buffer)*8 - 16 + s->bit_count; | |
457 | } | |
458 | ||
459 | #elif defined A32_BITSTREAM_READER | |
460 | ||
461 | # define MIN_CACHE_BITS 32 | |
462 | ||
463 | # define OPEN_READER(name, gb)\ | |
464 | int name##_bit_count=(gb)->bit_count;\ | |
465 | uint32_t name##_cache0= (gb)->cache0;\ | |
466 | uint32_t name##_cache1= (gb)->cache1;\ | |
467 | uint32_t * name##_buffer_ptr=(gb)->buffer_ptr;\ | |
468 | ||
469 | # define CLOSE_READER(name, gb)\ | |
470 | (gb)->bit_count= name##_bit_count;\ | |
471 | (gb)->cache0= name##_cache0;\ | |
472 | (gb)->cache1= name##_cache1;\ | |
473 | (gb)->buffer_ptr= name##_buffer_ptr;\ | |
474 | ||
475 | # define UPDATE_CACHE(name, gb)\ | |
476 | if(name##_bit_count > 0){\ | |
477 | const uint32_t next= be2me_32( *name##_buffer_ptr );\ | |
478 | name##_cache0 |= NEG_USR32(next,name##_bit_count);\ | |
479 | name##_cache1 |= next<<name##_bit_count;\ | |
480 | name##_buffer_ptr++;\ | |
481 | name##_bit_count-= 32;\ | |
482 | }\ | |
483 | ||
484 | #if defined(ARCH_X86) || defined(ARCH_X86_64) | |
485 | # define SKIP_CACHE(name, gb, num)\ | |
486 | asm(\ | |
487 | "shldl %2, %1, %0 \n\t"\ | |
488 | "shll %2, %1 \n\t"\ | |
489 | : "+r" (name##_cache0), "+r" (name##_cache1)\ | |
490 | : "Ic" ((uint8_t)num)\ | |
491 | ); | |
492 | #else | |
493 | # define SKIP_CACHE(name, gb, num)\ | |
494 | name##_cache0 <<= (num);\ | |
495 | name##_cache0 |= NEG_USR32(name##_cache1,num);\ | |
496 | name##_cache1 <<= (num); | |
497 | #endif | |
498 | ||
499 | # define SKIP_COUNTER(name, gb, num)\ | |
500 | name##_bit_count += (num);\ | |
501 | ||
502 | # define SKIP_BITS(name, gb, num)\ | |
503 | {\ | |
504 | SKIP_CACHE(name, gb, num)\ | |
505 | SKIP_COUNTER(name, gb, num)\ | |
506 | }\ | |
507 | ||
508 | # define LAST_SKIP_BITS(name, gb, num) SKIP_BITS(name, gb, num) | |
509 | # define LAST_SKIP_CACHE(name, gb, num) SKIP_CACHE(name, gb, num) | |
510 | ||
511 | # define SHOW_UBITS(name, gb, num)\ | |
512 | NEG_USR32(name##_cache0, num) | |
513 | ||
514 | # define SHOW_SBITS(name, gb, num)\ | |
515 | NEG_SSR32(name##_cache0, num) | |
516 | ||
517 | # define GET_CACHE(name, gb)\ | |
518 | (name##_cache0) | |
519 | ||
520 | static inline int get_bits_count(GetBitContext *s){ | |
521 | return ((uint8_t*)s->buffer_ptr - s->buffer)*8 - 32 + s->bit_count; | |
522 | } | |
523 | ||
524 | #endif | |
525 | ||
526 | /** | |
527 | * read mpeg1 dc style vlc (sign bit + mantisse with no MSB). | |
528 | * if MSB not set it is negative | |
529 | * @param n length in bits | |
530 | * @author BERO | |
531 | */ | |
532 | static inline int get_xbits(GetBitContext *s, int n){ | |
533 | register int tmp; | |
534 | register int32_t cache; | |
535 | OPEN_READER(re, s) | |
536 | UPDATE_CACHE(re, s) | |
537 | cache = GET_CACHE(re,s); | |
538 | if ((int32_t)cache<0) { //MSB=1 | |
539 | tmp = NEG_USR32(cache,n); | |
540 | } else { | |
541 | // tmp = (-1<<n) | NEG_USR32(cache,n) + 1; mpeg12.c algo | |
542 | // tmp = - (NEG_USR32(cache,n) ^ ((1 << n) - 1)); h263.c algo | |
543 | tmp = - NEG_USR32(~cache,n); | |
544 | } | |
545 | LAST_SKIP_BITS(re, s, n) | |
546 | CLOSE_READER(re, s) | |
547 | return tmp; | |
548 | } | |
549 | ||
550 | static inline int get_sbits(GetBitContext *s, int n){ | |
551 | register int tmp; | |
552 | OPEN_READER(re, s) | |
553 | UPDATE_CACHE(re, s) | |
554 | tmp= SHOW_SBITS(re, s, n); | |
555 | LAST_SKIP_BITS(re, s, n) | |
556 | CLOSE_READER(re, s) | |
557 | return tmp; | |
558 | } | |
559 | ||
560 | /** | |
561 | * reads 0-17 bits. | |
562 | * Note, the alt bitstream reader can read upto 25 bits, but the libmpeg2 reader cant | |
563 | */ | |
564 | static inline unsigned int get_bits(GetBitContext *s, int n){ | |
565 | register int tmp; | |
566 | OPEN_READER(re, s) | |
567 | UPDATE_CACHE(re, s) | |
568 | tmp= SHOW_UBITS(re, s, n); | |
569 | LAST_SKIP_BITS(re, s, n) | |
570 | CLOSE_READER(re, s) | |
571 | return tmp; | |
572 | } | |
573 | ||
574 | unsigned int get_bits_long(GetBitContext *s, int n); | |
575 | ||
576 | /** | |
577 | * shows 0-17 bits. | |
578 | * Note, the alt bitstream reader can read upto 25 bits, but the libmpeg2 reader cant | |
579 | */ | |
580 | static inline unsigned int show_bits(GetBitContext *s, int n){ | |
581 | register int tmp; | |
582 | OPEN_READER(re, s) | |
583 | UPDATE_CACHE(re, s) | |
584 | tmp= SHOW_UBITS(re, s, n); | |
585 | // CLOSE_READER(re, s) | |
586 | return tmp; | |
587 | } | |
588 | ||
589 | unsigned int show_bits_long(GetBitContext *s, int n); | |
590 | ||
591 | static inline void skip_bits(GetBitContext *s, int n){ | |
592 | //Note gcc seems to optimize this to s->index+=n for the ALT_READER :)) | |
593 | OPEN_READER(re, s) | |
594 | UPDATE_CACHE(re, s) | |
595 | LAST_SKIP_BITS(re, s, n) | |
596 | CLOSE_READER(re, s) | |
597 | } | |
598 | ||
599 | static inline unsigned int get_bits1(GetBitContext *s){ | |
600 | #ifdef ALT_BITSTREAM_READER | |
601 | int index= s->index; | |
602 | uint8_t result= s->buffer[ index>>3 ]; | |
603 | result<<= (index&0x07); | |
604 | result>>= 8 - 1; | |
605 | index++; | |
606 | s->index= index; | |
607 | ||
608 | return result; | |
609 | #else | |
610 | return get_bits(s, 1); | |
611 | #endif | |
612 | } | |
613 | ||
614 | static inline unsigned int show_bits1(GetBitContext *s){ | |
615 | return show_bits(s, 1); | |
616 | } | |
617 | ||
618 | static inline void skip_bits1(GetBitContext *s){ | |
619 | skip_bits(s, 1); | |
620 | } | |
621 | ||
622 | /** | |
623 | * init GetBitContext. | |
624 | * @param buffer bitstream buffer, must be FF_INPUT_BUFFER_PADDING_SIZE bytes larger then the actual read bits | |
625 | * because some optimized bitstream readers read 32 or 64 bit at once and could read over the end | |
626 | * @param bit_size the size of the buffer in bits | |
627 | */ | |
628 | static inline void init_get_bits(GetBitContext *s, | |
629 | const uint8_t *buffer, int bit_size) | |
630 | { | |
631 | const int buffer_size= (bit_size+7)>>3; | |
632 | ||
633 | s->buffer= buffer; | |
634 | s->size_in_bits= bit_size; | |
635 | s->buffer_end= buffer + buffer_size; | |
636 | #ifdef ALT_BITSTREAM_READER | |
637 | s->index=0; | |
638 | #elif defined LIBMPEG2_BITSTREAM_READER | |
639 | #ifdef LIBMPEG2_BITSTREAM_READER_HACK | |
640 | if ((int)buffer&1) { | |
641 | /* word alignment */ | |
642 | s->cache = (*buffer++)<<24; | |
643 | s->buffer_ptr = buffer; | |
644 | s->bit_count = 16-8; | |
645 | } else | |
646 | #endif | |
647 | { | |
648 | s->buffer_ptr = buffer; | |
649 | s->bit_count = 16; | |
650 | s->cache = 0; | |
651 | } | |
652 | #elif defined A32_BITSTREAM_READER | |
653 | s->buffer_ptr = (uint32_t*)buffer; | |
654 | s->bit_count = 32; | |
655 | s->cache0 = 0; | |
656 | s->cache1 = 0; | |
657 | #endif | |
658 | { | |
659 | OPEN_READER(re, s) | |
660 | UPDATE_CACHE(re, s) | |
661 | UPDATE_CACHE(re, s) | |
662 | CLOSE_READER(re, s) | |
663 | } | |
664 | #ifdef A32_BITSTREAM_READER | |
665 | s->cache1 = 0; | |
666 | #endif | |
667 | } | |
668 | ||
669 | int check_marker(GetBitContext *s, const char *msg); | |
670 | void align_get_bits(GetBitContext *s); | |
671 | int init_vlc(VLC *vlc, int nb_bits, int nb_codes, | |
672 | const void *bits, int bits_wrap, int bits_size, | |
673 | const void *codes, int codes_wrap, int codes_size, | |
674 | int use_static); | |
675 | void free_vlc(VLC *vlc); | |
676 | ||
677 | /** | |
678 | * | |
679 | * if the vlc code is invalid and max_depth=1 than no bits will be removed | |
680 | * if the vlc code is invalid and max_depth>1 than the number of bits removed | |
681 | * is undefined | |
682 | */ | |
683 | #define GET_VLC(code, name, gb, table, bits, max_depth)\ | |
684 | {\ | |
685 | int n, index, nb_bits;\ | |
686 | \ | |
687 | index= SHOW_UBITS(name, gb, bits);\ | |
688 | code = table[index][0];\ | |
689 | n = table[index][1];\ | |
690 | \ | |
691 | if(max_depth > 1 && n < 0){\ | |
692 | LAST_SKIP_BITS(name, gb, bits)\ | |
693 | UPDATE_CACHE(name, gb)\ | |
694 | \ | |
695 | nb_bits = -n;\ | |
696 | \ | |
697 | index= SHOW_UBITS(name, gb, nb_bits) + code;\ | |
698 | code = table[index][0];\ | |
699 | n = table[index][1];\ | |
700 | if(max_depth > 2 && n < 0){\ | |
701 | LAST_SKIP_BITS(name, gb, nb_bits)\ | |
702 | UPDATE_CACHE(name, gb)\ | |
703 | \ | |
704 | nb_bits = -n;\ | |
705 | \ | |
706 | index= SHOW_UBITS(name, gb, nb_bits) + code;\ | |
707 | code = table[index][0];\ | |
708 | n = table[index][1];\ | |
709 | }\ | |
710 | }\ | |
711 | SKIP_BITS(name, gb, n)\ | |
712 | } | |
713 | ||
714 | #define GET_RL_VLC(level, run, name, gb, table, bits, max_depth)\ | |
715 | {\ | |
716 | int n, index, nb_bits;\ | |
717 | \ | |
718 | index= SHOW_UBITS(name, gb, bits);\ | |
719 | level = table[index].level;\ | |
720 | n = table[index].len;\ | |
721 | \ | |
722 | if(max_depth > 1 && n < 0){\ | |
723 | LAST_SKIP_BITS(name, gb, bits)\ | |
724 | UPDATE_CACHE(name, gb)\ | |
725 | \ | |
726 | nb_bits = -n;\ | |
727 | \ | |
728 | index= SHOW_UBITS(name, gb, nb_bits) + level;\ | |
729 | level = table[index].level;\ | |
730 | n = table[index].len;\ | |
731 | }\ | |
732 | run= table[index].run;\ | |
733 | SKIP_BITS(name, gb, n)\ | |
734 | } | |
735 | ||
736 | // deprecated, dont use get_vlc for new code, use get_vlc2 instead or use GET_VLC directly | |
737 | static inline int get_vlc(GetBitContext *s, VLC *vlc) | |
738 | { | |
739 | int code; | |
740 | VLC_TYPE (*table)[2]= vlc->table; | |
741 | ||
742 | OPEN_READER(re, s) | |
743 | UPDATE_CACHE(re, s) | |
744 | ||
745 | GET_VLC(code, re, s, table, vlc->bits, 3) | |
746 | ||
747 | CLOSE_READER(re, s) | |
748 | return code; | |
749 | } | |
750 | ||
751 | /** | |
752 | * parses a vlc code, faster then get_vlc() | |
753 | * @param bits is the number of bits which will be read at once, must be | |
754 | * identical to nb_bits in init_vlc() | |
755 | * @param max_depth is the number of times bits bits must be readed to completly | |
756 | * read the longest vlc code | |
757 | * = (max_vlc_length + bits - 1) / bits | |
758 | */ | |
759 | static always_inline int get_vlc2(GetBitContext *s, VLC_TYPE (*table)[2], | |
760 | int bits, int max_depth) | |
761 | { | |
762 | int code; | |
763 | ||
764 | OPEN_READER(re, s) | |
765 | UPDATE_CACHE(re, s) | |
766 | ||
767 | GET_VLC(code, re, s, table, bits, max_depth) | |
768 | ||
769 | CLOSE_READER(re, s) | |
770 | return code; | |
771 | } | |
772 | ||
773 | //#define TRACE | |
774 | ||
775 | #ifdef TRACE | |
776 | ||
777 | static inline void print_bin(int bits, int n){ | |
778 | int i; | |
779 | ||
780 | for(i=n-1; i>=0; i--){ | |
781 | printf("%d", (bits>>i)&1); | |
782 | } | |
783 | for(i=n; i<24; i++) | |
784 | printf(" "); | |
785 | } | |
786 | ||
787 | static inline int get_bits_trace(GetBitContext *s, int n, char *file, char *func, int line){ | |
788 | int r= get_bits(s, n); | |
789 | ||
790 | print_bin(r, n); | |
791 | printf("%5d %2d %3d bit @%5d in %s %s:%d\n", r, n, r, get_bits_count(s)-n, file, func, line); | |
792 | return r; | |
793 | } | |
794 | static inline int get_vlc_trace(GetBitContext *s, VLC_TYPE (*table)[2], int bits, int max_depth, char *file, char *func, int line){ | |
795 | int show= show_bits(s, 24); | |
796 | int pos= get_bits_count(s); | |
797 | int r= get_vlc2(s, table, bits, max_depth); | |
798 | int len= get_bits_count(s) - pos; | |
799 | int bits2= show>>(24-len); | |
800 | ||
801 | print_bin(bits2, len); | |
802 | ||
803 | printf("%5d %2d %3d vlc @%5d in %s %s:%d\n", bits2, len, r, pos, file, func, line); | |
804 | return r; | |
805 | } | |
806 | static inline int get_xbits_trace(GetBitContext *s, int n, char *file, char *func, int line){ | |
807 | int show= show_bits(s, n); | |
808 | int r= get_xbits(s, n); | |
809 | ||
810 | print_bin(show, n); | |
811 | printf("%5d %2d %3d xbt @%5d in %s %s:%d\n", show, n, r, get_bits_count(s)-n, file, func, line); | |
812 | return r; | |
813 | } | |
814 | ||
815 | #define get_bits(s, n) get_bits_trace(s, n, __FILE__, __PRETTY_FUNCTION__, __LINE__) | |
816 | #define get_bits1(s) get_bits_trace(s, 1, __FILE__, __PRETTY_FUNCTION__, __LINE__) | |
817 | #define get_xbits(s, n) get_xbits_trace(s, n, __FILE__, __PRETTY_FUNCTION__, __LINE__) | |
818 | #define get_vlc(s, vlc) get_vlc_trace(s, (vlc)->table, (vlc)->bits, 3, __FILE__, __PRETTY_FUNCTION__, __LINE__) | |
819 | #define get_vlc2(s, tab, bits, max) get_vlc_trace(s, tab, bits, max, __FILE__, __PRETTY_FUNCTION__, __LINE__) | |
820 | ||
821 | #define tprintf(...) av_log(NULL, AV_LOG_DEBUG, __VA_ARGS__) | |
822 | ||
823 | #else //TRACE | |
824 | #define tprintf(...) {} | |
825 | #endif | |
826 | ||
827 | #endif /* BITSTREAM_H */ |