ce188d4d |
1 | /* libFLAC - Free Lossless Audio Codec library |
2 | * Copyright (C) 2000-2009 Josh Coalson |
3 | * Copyright (C) 2011-2016 Xiph.Org Foundation |
4 | * |
5 | * Redistribution and use in source and binary forms, with or without |
6 | * modification, are permitted provided that the following conditions |
7 | * are met: |
8 | * |
9 | * - Redistributions of source code must retain the above copyright |
10 | * notice, this list of conditions and the following disclaimer. |
11 | * |
12 | * - Redistributions in binary form must reproduce the above copyright |
13 | * notice, this list of conditions and the following disclaimer in the |
14 | * documentation and/or other materials provided with the distribution. |
15 | * |
16 | * - Neither the name of the Xiph.org Foundation nor the names of its |
17 | * contributors may be used to endorse or promote products derived from |
18 | * this software without specific prior written permission. |
19 | * |
20 | * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS |
21 | * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT |
22 | * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR |
23 | * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE FOUNDATION OR |
24 | * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, |
25 | * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, |
26 | * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR |
27 | * PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF |
28 | * LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING |
29 | * NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS |
30 | * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. |
31 | */ |
32 | |
33 | #ifdef HAVE_CONFIG_H |
34 | # include <config.h> |
35 | #endif |
36 | |
37 | #include <stdlib.h> |
38 | #include <string.h> |
39 | #include "private/bitwriter.h" |
40 | #include "private/crc.h" |
41 | #include "private/macros.h" |
42 | #include "FLAC/assert.h" |
43 | #include "share/alloc.h" |
44 | #include "share/compat.h" |
45 | #include "share/endswap.h" |
46 | |
47 | /* Things should be fastest when this matches the machine word size */ |
48 | /* WATCHOUT: if you change this you must also change the following #defines down to SWAP_BE_WORD_TO_HOST below to match */ |
49 | /* WATCHOUT: there are a few places where the code will not work unless bwword is >= 32 bits wide */ |
50 | |
51 | #if (ENABLE_64_BIT_WORDS == 0) |
52 | |
53 | typedef FLAC__uint32 bwword; |
54 | #define FLAC__BYTES_PER_WORD 4 /* sizeof bwword */ |
55 | #define FLAC__BITS_PER_WORD 32 |
56 | /* SWAP_BE_WORD_TO_HOST swaps bytes in a bwword (which is always big-endian) if necessary to match host byte order */ |
57 | #if WORDS_BIGENDIAN |
58 | #define SWAP_BE_WORD_TO_HOST(x) (x) |
59 | #else |
60 | #define SWAP_BE_WORD_TO_HOST(x) ENDSWAP_32(x) |
61 | #endif |
62 | |
63 | #else |
64 | |
65 | typedef FLAC__uint64 bwword; |
66 | #define FLAC__BYTES_PER_WORD 8 /* sizeof bwword */ |
67 | #define FLAC__BITS_PER_WORD 64 |
68 | /* SWAP_BE_WORD_TO_HOST swaps bytes in a bwword (which is always big-endian) if necessary to match host byte order */ |
69 | #if WORDS_BIGENDIAN |
70 | #define SWAP_BE_WORD_TO_HOST(x) (x) |
71 | #else |
72 | #define SWAP_BE_WORD_TO_HOST(x) ENDSWAP_64(x) |
73 | #endif |
74 | |
75 | #endif |
76 | |
77 | /* |
78 | * The default capacity here doesn't matter too much. The buffer always grows |
79 | * to hold whatever is written to it. Usually the encoder will stop adding at |
80 | * a frame or metadata block, then write that out and clear the buffer for the |
81 | * next one. |
82 | */ |
83 | static const unsigned FLAC__BITWRITER_DEFAULT_CAPACITY = 32768u / sizeof(bwword); /* size in words */ |
84 | /* When growing, increment 4K at a time */ |
85 | static const unsigned FLAC__BITWRITER_DEFAULT_INCREMENT = 4096u / sizeof(bwword); /* size in words */ |
86 | |
87 | #define FLAC__WORDS_TO_BITS(words) ((words) * FLAC__BITS_PER_WORD) |
88 | #define FLAC__TOTAL_BITS(bw) (FLAC__WORDS_TO_BITS((bw)->words) + (bw)->bits) |
89 | |
90 | struct FLAC__BitWriter { |
91 | bwword *buffer; |
92 | bwword accum; /* accumulator; bits are right-justified; when full, accum is appended to buffer */ |
93 | unsigned capacity; /* capacity of buffer in words */ |
94 | unsigned words; /* # of complete words in buffer */ |
95 | unsigned bits; /* # of used bits in accum */ |
96 | }; |
97 | |
98 | /* * WATCHOUT: The current implementation only grows the buffer. */ |
99 | #ifndef __SUNPRO_C |
100 | static |
101 | #endif |
102 | FLAC__bool bitwriter_grow_(FLAC__BitWriter *bw, unsigned bits_to_add) |
103 | { |
104 | unsigned new_capacity; |
105 | bwword *new_buffer; |
106 | |
107 | FLAC__ASSERT(0 != bw); |
108 | FLAC__ASSERT(0 != bw->buffer); |
109 | |
110 | /* calculate total words needed to store 'bits_to_add' additional bits */ |
111 | new_capacity = bw->words + ((bw->bits + bits_to_add + FLAC__BITS_PER_WORD - 1) / FLAC__BITS_PER_WORD); |
112 | |
113 | /* it's possible (due to pessimism in the growth estimation that |
114 | * leads to this call) that we don't actually need to grow |
115 | */ |
116 | if(bw->capacity >= new_capacity) |
117 | return true; |
118 | |
119 | /* round up capacity increase to the nearest FLAC__BITWRITER_DEFAULT_INCREMENT */ |
120 | if((new_capacity - bw->capacity) % FLAC__BITWRITER_DEFAULT_INCREMENT) |
121 | new_capacity += FLAC__BITWRITER_DEFAULT_INCREMENT - ((new_capacity - bw->capacity) % FLAC__BITWRITER_DEFAULT_INCREMENT); |
122 | /* make sure we got everything right */ |
123 | FLAC__ASSERT(0 == (new_capacity - bw->capacity) % FLAC__BITWRITER_DEFAULT_INCREMENT); |
124 | FLAC__ASSERT(new_capacity > bw->capacity); |
125 | FLAC__ASSERT(new_capacity >= bw->words + ((bw->bits + bits_to_add + FLAC__BITS_PER_WORD - 1) / FLAC__BITS_PER_WORD)); |
126 | |
127 | new_buffer = safe_realloc_mul_2op_(bw->buffer, sizeof(bwword), /*times*/new_capacity); |
128 | if(new_buffer == 0) |
129 | return false; |
130 | bw->buffer = new_buffer; |
131 | bw->capacity = new_capacity; |
132 | return true; |
133 | } |
134 | |
135 | |
136 | /*********************************************************************** |
137 | * |
138 | * Class constructor/destructor |
139 | * |
140 | ***********************************************************************/ |
141 | |
142 | FLAC__BitWriter *FLAC__bitwriter_new(void) |
143 | { |
144 | FLAC__BitWriter *bw = calloc(1, sizeof(FLAC__BitWriter)); |
145 | /* note that calloc() sets all members to 0 for us */ |
146 | return bw; |
147 | } |
148 | |
149 | void FLAC__bitwriter_delete(FLAC__BitWriter *bw) |
150 | { |
151 | FLAC__ASSERT(0 != bw); |
152 | |
153 | FLAC__bitwriter_free(bw); |
154 | free(bw); |
155 | } |
156 | |
157 | /*********************************************************************** |
158 | * |
159 | * Public class methods |
160 | * |
161 | ***********************************************************************/ |
162 | |
163 | FLAC__bool FLAC__bitwriter_init(FLAC__BitWriter *bw) |
164 | { |
165 | FLAC__ASSERT(0 != bw); |
166 | |
167 | bw->words = bw->bits = 0; |
168 | bw->capacity = FLAC__BITWRITER_DEFAULT_CAPACITY; |
169 | bw->buffer = malloc(sizeof(bwword) * bw->capacity); |
170 | if(bw->buffer == 0) |
171 | return false; |
172 | |
173 | return true; |
174 | } |
175 | |
176 | void FLAC__bitwriter_free(FLAC__BitWriter *bw) |
177 | { |
178 | FLAC__ASSERT(0 != bw); |
179 | |
180 | if(0 != bw->buffer) |
181 | free(bw->buffer); |
182 | bw->buffer = 0; |
183 | bw->capacity = 0; |
184 | bw->words = bw->bits = 0; |
185 | } |
186 | |
187 | void FLAC__bitwriter_clear(FLAC__BitWriter *bw) |
188 | { |
189 | bw->words = bw->bits = 0; |
190 | } |
191 | |
192 | void FLAC__bitwriter_dump(const FLAC__BitWriter *bw, FILE *out) |
193 | { |
194 | unsigned i, j; |
195 | if(bw == 0) { |
196 | fprintf(out, "bitwriter is NULL\n"); |
197 | } |
198 | else { |
199 | fprintf(out, "bitwriter: capacity=%u words=%u bits=%u total_bits=%u\n", bw->capacity, bw->words, bw->bits, FLAC__TOTAL_BITS(bw)); |
200 | |
201 | for(i = 0; i < bw->words; i++) { |
202 | fprintf(out, "%08X: ", i); |
203 | for(j = 0; j < FLAC__BITS_PER_WORD; j++) |
204 | fprintf(out, "%01u", bw->buffer[i] & ((bwword)1 << (FLAC__BITS_PER_WORD-j-1)) ? 1:0); |
205 | fprintf(out, "\n"); |
206 | } |
207 | if(bw->bits > 0) { |
208 | fprintf(out, "%08X: ", i); |
209 | for(j = 0; j < bw->bits; j++) |
210 | fprintf(out, "%01u", bw->accum & ((bwword)1 << (bw->bits-j-1)) ? 1:0); |
211 | fprintf(out, "\n"); |
212 | } |
213 | } |
214 | } |
215 | |
216 | FLAC__bool FLAC__bitwriter_get_write_crc16(FLAC__BitWriter *bw, FLAC__uint16 *crc) |
217 | { |
218 | const FLAC__byte *buffer; |
219 | size_t bytes; |
220 | |
221 | FLAC__ASSERT((bw->bits & 7) == 0); /* assert that we're byte-aligned */ |
222 | |
223 | if(!FLAC__bitwriter_get_buffer(bw, &buffer, &bytes)) |
224 | return false; |
225 | |
226 | *crc = (FLAC__uint16)FLAC__crc16(buffer, bytes); |
227 | FLAC__bitwriter_release_buffer(bw); |
228 | return true; |
229 | } |
230 | |
231 | FLAC__bool FLAC__bitwriter_get_write_crc8(FLAC__BitWriter *bw, FLAC__byte *crc) |
232 | { |
233 | const FLAC__byte *buffer; |
234 | size_t bytes; |
235 | |
236 | FLAC__ASSERT((bw->bits & 7) == 0); /* assert that we're byte-aligned */ |
237 | |
238 | if(!FLAC__bitwriter_get_buffer(bw, &buffer, &bytes)) |
239 | return false; |
240 | |
241 | *crc = FLAC__crc8(buffer, bytes); |
242 | FLAC__bitwriter_release_buffer(bw); |
243 | return true; |
244 | } |
245 | |
246 | FLAC__bool FLAC__bitwriter_is_byte_aligned(const FLAC__BitWriter *bw) |
247 | { |
248 | return ((bw->bits & 7) == 0); |
249 | } |
250 | |
251 | unsigned FLAC__bitwriter_get_input_bits_unconsumed(const FLAC__BitWriter *bw) |
252 | { |
253 | return FLAC__TOTAL_BITS(bw); |
254 | } |
255 | |
256 | FLAC__bool FLAC__bitwriter_get_buffer(FLAC__BitWriter *bw, const FLAC__byte **buffer, size_t *bytes) |
257 | { |
258 | FLAC__ASSERT((bw->bits & 7) == 0); |
259 | /* double protection */ |
260 | if(bw->bits & 7) |
261 | return false; |
262 | /* if we have bits in the accumulator we have to flush those to the buffer first */ |
263 | if(bw->bits) { |
264 | FLAC__ASSERT(bw->words <= bw->capacity); |
265 | if(bw->words == bw->capacity && !bitwriter_grow_(bw, FLAC__BITS_PER_WORD)) |
266 | return false; |
267 | /* append bits as complete word to buffer, but don't change bw->accum or bw->bits */ |
268 | bw->buffer[bw->words] = SWAP_BE_WORD_TO_HOST(bw->accum << (FLAC__BITS_PER_WORD-bw->bits)); |
269 | } |
270 | /* now we can just return what we have */ |
271 | *buffer = (FLAC__byte*)bw->buffer; |
272 | *bytes = (FLAC__BYTES_PER_WORD * bw->words) + (bw->bits >> 3); |
273 | return true; |
274 | } |
275 | |
276 | void FLAC__bitwriter_release_buffer(FLAC__BitWriter *bw) |
277 | { |
278 | /* nothing to do. in the future, strict checking of a 'writer-is-in- |
279 | * get-mode' flag could be added everywhere and then cleared here |
280 | */ |
281 | (void)bw; |
282 | } |
283 | |
284 | inline FLAC__bool FLAC__bitwriter_write_zeroes(FLAC__BitWriter *bw, unsigned bits) |
285 | { |
286 | unsigned n; |
287 | |
288 | FLAC__ASSERT(0 != bw); |
289 | FLAC__ASSERT(0 != bw->buffer); |
290 | |
291 | if(bits == 0) |
292 | return true; |
293 | /* slightly pessimistic size check but faster than "<= bw->words + (bw->bits+bits+FLAC__BITS_PER_WORD-1)/FLAC__BITS_PER_WORD" */ |
294 | if(bw->capacity <= bw->words + bits && !bitwriter_grow_(bw, bits)) |
295 | return false; |
296 | /* first part gets to word alignment */ |
297 | if(bw->bits) { |
298 | n = flac_min(FLAC__BITS_PER_WORD - bw->bits, bits); |
299 | bw->accum <<= n; |
300 | bits -= n; |
301 | bw->bits += n; |
302 | if(bw->bits == FLAC__BITS_PER_WORD) { |
303 | bw->buffer[bw->words++] = SWAP_BE_WORD_TO_HOST(bw->accum); |
304 | bw->bits = 0; |
305 | } |
306 | else |
307 | return true; |
308 | } |
309 | /* do whole words */ |
310 | while(bits >= FLAC__BITS_PER_WORD) { |
311 | bw->buffer[bw->words++] = 0; |
312 | bits -= FLAC__BITS_PER_WORD; |
313 | } |
314 | /* do any leftovers */ |
315 | if(bits > 0) { |
316 | bw->accum = 0; |
317 | bw->bits = bits; |
318 | } |
319 | return true; |
320 | } |
321 | |
322 | static inline FLAC__bool FLAC__bitwriter_write_raw_uint32_nocheck(FLAC__BitWriter *bw, FLAC__uint32 val, unsigned bits) |
323 | { |
324 | register unsigned left; |
325 | |
326 | /* WATCHOUT: code does not work with <32bit words; we can make things much faster with this assertion */ |
327 | FLAC__ASSERT(FLAC__BITS_PER_WORD >= 32); |
328 | |
329 | if(bw == 0 || bw->buffer == 0) |
330 | return false; |
331 | |
332 | if (bits > 32) |
333 | return false; |
334 | |
335 | if(bits == 0) |
336 | return true; |
337 | |
338 | FLAC__ASSERT((bits == 32) || (val>>bits == 0)); |
339 | |
340 | /* slightly pessimistic size check but faster than "<= bw->words + (bw->bits+bits+FLAC__BITS_PER_WORD-1)/FLAC__BITS_PER_WORD" */ |
341 | if(bw->capacity <= bw->words + bits && !bitwriter_grow_(bw, bits)) |
342 | return false; |
343 | |
344 | left = FLAC__BITS_PER_WORD - bw->bits; |
345 | if(bits < left) { |
346 | bw->accum <<= bits; |
347 | bw->accum |= val; |
348 | bw->bits += bits; |
349 | } |
350 | else if(bw->bits) { /* WATCHOUT: if bw->bits == 0, left==FLAC__BITS_PER_WORD and bw->accum<<=left is a NOP instead of setting to 0 */ |
351 | bw->accum <<= left; |
352 | bw->accum |= val >> (bw->bits = bits - left); |
353 | bw->buffer[bw->words++] = SWAP_BE_WORD_TO_HOST(bw->accum); |
354 | bw->accum = val; /* unused top bits can contain garbage */ |
355 | } |
356 | else { /* at this point bits == FLAC__BITS_PER_WORD == 32 and bw->bits == 0 */ |
357 | bw->buffer[bw->words++] = SWAP_BE_WORD_TO_HOST((bwword)val); |
358 | } |
359 | |
360 | return true; |
361 | } |
362 | |
363 | inline FLAC__bool FLAC__bitwriter_write_raw_uint32(FLAC__BitWriter *bw, FLAC__uint32 val, unsigned bits) |
364 | { |
365 | /* check that unused bits are unset */ |
366 | if((bits < 32) && (val>>bits != 0)) |
367 | return false; |
368 | |
369 | return FLAC__bitwriter_write_raw_uint32_nocheck(bw, val, bits); |
370 | } |
371 | |
372 | inline FLAC__bool FLAC__bitwriter_write_raw_int32(FLAC__BitWriter *bw, FLAC__int32 val, unsigned bits) |
373 | { |
374 | /* zero-out unused bits */ |
375 | if(bits < 32) |
376 | val &= (~(0xffffffff << bits)); |
377 | |
378 | return FLAC__bitwriter_write_raw_uint32_nocheck(bw, (FLAC__uint32)val, bits); |
379 | } |
380 | |
381 | inline FLAC__bool FLAC__bitwriter_write_raw_uint64(FLAC__BitWriter *bw, FLAC__uint64 val, unsigned bits) |
382 | { |
383 | /* this could be a little faster but it's not used for much */ |
384 | if(bits > 32) { |
385 | return |
386 | FLAC__bitwriter_write_raw_uint32(bw, (FLAC__uint32)(val>>32), bits-32) && |
387 | FLAC__bitwriter_write_raw_uint32_nocheck(bw, (FLAC__uint32)val, 32); |
388 | } |
389 | else |
390 | return FLAC__bitwriter_write_raw_uint32(bw, (FLAC__uint32)val, bits); |
391 | } |
392 | |
393 | inline FLAC__bool FLAC__bitwriter_write_raw_uint32_little_endian(FLAC__BitWriter *bw, FLAC__uint32 val) |
394 | { |
395 | /* this doesn't need to be that fast as currently it is only used for vorbis comments */ |
396 | |
397 | if(!FLAC__bitwriter_write_raw_uint32_nocheck(bw, val & 0xff, 8)) |
398 | return false; |
399 | if(!FLAC__bitwriter_write_raw_uint32_nocheck(bw, (val>>8) & 0xff, 8)) |
400 | return false; |
401 | if(!FLAC__bitwriter_write_raw_uint32_nocheck(bw, (val>>16) & 0xff, 8)) |
402 | return false; |
403 | if(!FLAC__bitwriter_write_raw_uint32_nocheck(bw, val>>24, 8)) |
404 | return false; |
405 | |
406 | return true; |
407 | } |
408 | |
409 | inline FLAC__bool FLAC__bitwriter_write_byte_block(FLAC__BitWriter *bw, const FLAC__byte vals[], unsigned nvals) |
410 | { |
411 | unsigned i; |
412 | |
413 | /* this could be faster but currently we don't need it to be since it's only used for writing metadata */ |
414 | for(i = 0; i < nvals; i++) { |
415 | if(!FLAC__bitwriter_write_raw_uint32_nocheck(bw, (FLAC__uint32)(vals[i]), 8)) |
416 | return false; |
417 | } |
418 | |
419 | return true; |
420 | } |
421 | |
422 | FLAC__bool FLAC__bitwriter_write_unary_unsigned(FLAC__BitWriter *bw, unsigned val) |
423 | { |
424 | if(val < 32) |
425 | return FLAC__bitwriter_write_raw_uint32_nocheck(bw, 1, ++val); |
426 | else |
427 | return |
428 | FLAC__bitwriter_write_zeroes(bw, val) && |
429 | FLAC__bitwriter_write_raw_uint32_nocheck(bw, 1, 1); |
430 | } |
431 | |
432 | unsigned FLAC__bitwriter_rice_bits(FLAC__int32 val, unsigned parameter) |
433 | { |
434 | FLAC__uint32 uval; |
435 | |
436 | FLAC__ASSERT(parameter < 32); |
437 | |
438 | /* fold signed to unsigned; actual formula is: negative(v)? -2v-1 : 2v */ |
439 | uval = val; |
440 | uval <<= 1; |
441 | uval ^= (val>>31); |
442 | |
443 | return 1 + parameter + (uval >> parameter); |
444 | } |
445 | |
446 | #if 0 /* UNUSED */ |
447 | unsigned FLAC__bitwriter_golomb_bits_signed(int val, unsigned parameter) |
448 | { |
449 | unsigned bits, msbs, uval; |
450 | unsigned k; |
451 | |
452 | FLAC__ASSERT(parameter > 0); |
453 | |
454 | /* fold signed to unsigned */ |
455 | if(val < 0) |
456 | uval = (unsigned)(((-(++val)) << 1) + 1); |
457 | else |
458 | uval = (unsigned)(val << 1); |
459 | |
460 | k = FLAC__bitmath_ilog2(parameter); |
461 | if(parameter == 1u<<k) { |
462 | FLAC__ASSERT(k <= 30); |
463 | |
464 | msbs = uval >> k; |
465 | bits = 1 + k + msbs; |
466 | } |
467 | else { |
468 | unsigned q, r, d; |
469 | |
470 | d = (1 << (k+1)) - parameter; |
471 | q = uval / parameter; |
472 | r = uval - (q * parameter); |
473 | |
474 | bits = 1 + q + k; |
475 | if(r >= d) |
476 | bits++; |
477 | } |
478 | return bits; |
479 | } |
480 | |
481 | unsigned FLAC__bitwriter_golomb_bits_unsigned(unsigned uval, unsigned parameter) |
482 | { |
483 | unsigned bits, msbs; |
484 | unsigned k; |
485 | |
486 | FLAC__ASSERT(parameter > 0); |
487 | |
488 | k = FLAC__bitmath_ilog2(parameter); |
489 | if(parameter == 1u<<k) { |
490 | FLAC__ASSERT(k <= 30); |
491 | |
492 | msbs = uval >> k; |
493 | bits = 1 + k + msbs; |
494 | } |
495 | else { |
496 | unsigned q, r, d; |
497 | |
498 | d = (1 << (k+1)) - parameter; |
499 | q = uval / parameter; |
500 | r = uval - (q * parameter); |
501 | |
502 | bits = 1 + q + k; |
503 | if(r >= d) |
504 | bits++; |
505 | } |
506 | return bits; |
507 | } |
508 | #endif /* UNUSED */ |
509 | |
510 | FLAC__bool FLAC__bitwriter_write_rice_signed(FLAC__BitWriter *bw, FLAC__int32 val, unsigned parameter) |
511 | { |
512 | unsigned total_bits, interesting_bits, msbs; |
513 | FLAC__uint32 uval, pattern; |
514 | |
515 | FLAC__ASSERT(0 != bw); |
516 | FLAC__ASSERT(0 != bw->buffer); |
517 | FLAC__ASSERT(parameter < 32); |
518 | |
519 | /* fold signed to unsigned; actual formula is: negative(v)? -2v-1 : 2v */ |
520 | uval = val; |
521 | uval <<= 1; |
522 | uval ^= (val>>31); |
523 | |
524 | msbs = uval >> parameter; |
525 | interesting_bits = 1 + parameter; |
526 | total_bits = interesting_bits + msbs; |
527 | pattern = 1 << parameter; /* the unary end bit */ |
528 | pattern |= (uval & ((1<<parameter)-1)); /* the binary LSBs */ |
529 | |
530 | if(total_bits <= 32) |
531 | return FLAC__bitwriter_write_raw_uint32(bw, pattern, total_bits); |
532 | else |
533 | return |
534 | FLAC__bitwriter_write_zeroes(bw, msbs) && /* write the unary MSBs */ |
535 | FLAC__bitwriter_write_raw_uint32(bw, pattern, interesting_bits); /* write the unary end bit and binary LSBs */ |
536 | } |
537 | |
538 | FLAC__bool FLAC__bitwriter_write_rice_signed_block(FLAC__BitWriter *bw, const FLAC__int32 *vals, unsigned nvals, unsigned parameter) |
539 | { |
540 | const FLAC__uint32 mask1 = (FLAC__uint32)0xffffffff << parameter; /* we val|=mask1 to set the stop bit above it... */ |
541 | const FLAC__uint32 mask2 = (FLAC__uint32)0xffffffff >> (31-parameter); /* ...then mask off the bits above the stop bit with val&=mask2 */ |
542 | FLAC__uint32 uval; |
543 | unsigned left; |
544 | const unsigned lsbits = 1 + parameter; |
545 | unsigned msbits, total_bits; |
546 | |
547 | FLAC__ASSERT(0 != bw); |
548 | FLAC__ASSERT(0 != bw->buffer); |
549 | FLAC__ASSERT(parameter < 31); |
550 | /* WATCHOUT: code does not work with <32bit words; we can make things much faster with this assertion */ |
551 | FLAC__ASSERT(FLAC__BITS_PER_WORD >= 32); |
552 | |
553 | while(nvals) { |
554 | /* fold signed to unsigned; actual formula is: negative(v)? -2v-1 : 2v */ |
555 | uval = *vals; |
556 | uval <<= 1; |
557 | uval ^= (*vals>>31); |
558 | |
559 | msbits = uval >> parameter; |
560 | total_bits = lsbits + msbits; |
561 | |
562 | if(bw->bits && bw->bits + total_bits < FLAC__BITS_PER_WORD) { /* i.e. if the whole thing fits in the current bwword */ |
563 | /* ^^^ if bw->bits is 0 then we may have filled the buffer and have no free bwword to work in */ |
564 | bw->bits += total_bits; |
565 | uval |= mask1; /* set stop bit */ |
566 | uval &= mask2; /* mask off unused top bits */ |
567 | bw->accum <<= total_bits; |
568 | bw->accum |= uval; |
569 | } |
570 | else { |
571 | /* slightly pessimistic size check but faster than "<= bw->words + (bw->bits+msbits+lsbits+FLAC__BITS_PER_WORD-1)/FLAC__BITS_PER_WORD" */ |
572 | /* OPT: pessimism may cause flurry of false calls to grow_ which eat up all savings before it */ |
573 | if(bw->capacity <= bw->words + bw->bits + msbits + 1 /* lsbits always fit in 1 bwword */ && !bitwriter_grow_(bw, total_bits)) |
574 | return false; |
575 | |
576 | if(msbits) { |
577 | /* first part gets to word alignment */ |
578 | if(bw->bits) { |
579 | left = FLAC__BITS_PER_WORD - bw->bits; |
580 | if(msbits < left) { |
581 | bw->accum <<= msbits; |
582 | bw->bits += msbits; |
583 | goto break1; |
584 | } |
585 | else { |
586 | bw->accum <<= left; |
587 | msbits -= left; |
588 | bw->buffer[bw->words++] = SWAP_BE_WORD_TO_HOST(bw->accum); |
589 | bw->bits = 0; |
590 | } |
591 | } |
592 | /* do whole words */ |
593 | while(msbits >= FLAC__BITS_PER_WORD) { |
594 | bw->buffer[bw->words++] = 0; |
595 | msbits -= FLAC__BITS_PER_WORD; |
596 | } |
597 | /* do any leftovers */ |
598 | if(msbits > 0) { |
599 | bw->accum = 0; |
600 | bw->bits = msbits; |
601 | } |
602 | } |
603 | break1: |
604 | uval |= mask1; /* set stop bit */ |
605 | uval &= mask2; /* mask off unused top bits */ |
606 | |
607 | left = FLAC__BITS_PER_WORD - bw->bits; |
608 | if(lsbits < left) { |
609 | bw->accum <<= lsbits; |
610 | bw->accum |= uval; |
611 | bw->bits += lsbits; |
612 | } |
613 | else { |
614 | /* if bw->bits == 0, left==FLAC__BITS_PER_WORD which will always |
615 | * be > lsbits (because of previous assertions) so it would have |
616 | * triggered the (lsbits<left) case above. |
617 | */ |
618 | FLAC__ASSERT(bw->bits); |
619 | FLAC__ASSERT(left < FLAC__BITS_PER_WORD); |
620 | bw->accum <<= left; |
621 | bw->accum |= uval >> (bw->bits = lsbits - left); |
622 | bw->buffer[bw->words++] = SWAP_BE_WORD_TO_HOST(bw->accum); |
623 | bw->accum = uval; /* unused top bits can contain garbage */ |
624 | } |
625 | } |
626 | vals++; |
627 | nvals--; |
628 | } |
629 | return true; |
630 | } |
631 | |
632 | #if 0 /* UNUSED */ |
633 | FLAC__bool FLAC__bitwriter_write_golomb_signed(FLAC__BitWriter *bw, int val, unsigned parameter) |
634 | { |
635 | unsigned total_bits, msbs, uval; |
636 | unsigned k; |
637 | |
638 | FLAC__ASSERT(0 != bw); |
639 | FLAC__ASSERT(0 != bw->buffer); |
640 | FLAC__ASSERT(parameter > 0); |
641 | |
642 | /* fold signed to unsigned */ |
643 | if(val < 0) |
644 | uval = (unsigned)(((-(++val)) << 1) + 1); |
645 | else |
646 | uval = (unsigned)(val << 1); |
647 | |
648 | k = FLAC__bitmath_ilog2(parameter); |
649 | if(parameter == 1u<<k) { |
650 | unsigned pattern; |
651 | |
652 | FLAC__ASSERT(k <= 30); |
653 | |
654 | msbs = uval >> k; |
655 | total_bits = 1 + k + msbs; |
656 | pattern = 1 << k; /* the unary end bit */ |
657 | pattern |= (uval & ((1u<<k)-1)); /* the binary LSBs */ |
658 | |
659 | if(total_bits <= 32) { |
660 | if(!FLAC__bitwriter_write_raw_uint32(bw, pattern, total_bits)) |
661 | return false; |
662 | } |
663 | else { |
664 | /* write the unary MSBs */ |
665 | if(!FLAC__bitwriter_write_zeroes(bw, msbs)) |
666 | return false; |
667 | /* write the unary end bit and binary LSBs */ |
668 | if(!FLAC__bitwriter_write_raw_uint32(bw, pattern, k+1)) |
669 | return false; |
670 | } |
671 | } |
672 | else { |
673 | unsigned q, r, d; |
674 | |
675 | d = (1 << (k+1)) - parameter; |
676 | q = uval / parameter; |
677 | r = uval - (q * parameter); |
678 | /* write the unary MSBs */ |
679 | if(!FLAC__bitwriter_write_zeroes(bw, q)) |
680 | return false; |
681 | /* write the unary end bit */ |
682 | if(!FLAC__bitwriter_write_raw_uint32(bw, 1, 1)) |
683 | return false; |
684 | /* write the binary LSBs */ |
685 | if(r >= d) { |
686 | if(!FLAC__bitwriter_write_raw_uint32(bw, r+d, k+1)) |
687 | return false; |
688 | } |
689 | else { |
690 | if(!FLAC__bitwriter_write_raw_uint32(bw, r, k)) |
691 | return false; |
692 | } |
693 | } |
694 | return true; |
695 | } |
696 | |
697 | FLAC__bool FLAC__bitwriter_write_golomb_unsigned(FLAC__BitWriter *bw, unsigned uval, unsigned parameter) |
698 | { |
699 | unsigned total_bits, msbs; |
700 | unsigned k; |
701 | |
702 | FLAC__ASSERT(0 != bw); |
703 | FLAC__ASSERT(0 != bw->buffer); |
704 | FLAC__ASSERT(parameter > 0); |
705 | |
706 | k = FLAC__bitmath_ilog2(parameter); |
707 | if(parameter == 1u<<k) { |
708 | unsigned pattern; |
709 | |
710 | FLAC__ASSERT(k <= 30); |
711 | |
712 | msbs = uval >> k; |
713 | total_bits = 1 + k + msbs; |
714 | pattern = 1 << k; /* the unary end bit */ |
715 | pattern |= (uval & ((1u<<k)-1)); /* the binary LSBs */ |
716 | |
717 | if(total_bits <= 32) { |
718 | if(!FLAC__bitwriter_write_raw_uint32(bw, pattern, total_bits)) |
719 | return false; |
720 | } |
721 | else { |
722 | /* write the unary MSBs */ |
723 | if(!FLAC__bitwriter_write_zeroes(bw, msbs)) |
724 | return false; |
725 | /* write the unary end bit and binary LSBs */ |
726 | if(!FLAC__bitwriter_write_raw_uint32(bw, pattern, k+1)) |
727 | return false; |
728 | } |
729 | } |
730 | else { |
731 | unsigned q, r, d; |
732 | |
733 | d = (1 << (k+1)) - parameter; |
734 | q = uval / parameter; |
735 | r = uval - (q * parameter); |
736 | /* write the unary MSBs */ |
737 | if(!FLAC__bitwriter_write_zeroes(bw, q)) |
738 | return false; |
739 | /* write the unary end bit */ |
740 | if(!FLAC__bitwriter_write_raw_uint32(bw, 1, 1)) |
741 | return false; |
742 | /* write the binary LSBs */ |
743 | if(r >= d) { |
744 | if(!FLAC__bitwriter_write_raw_uint32(bw, r+d, k+1)) |
745 | return false; |
746 | } |
747 | else { |
748 | if(!FLAC__bitwriter_write_raw_uint32(bw, r, k)) |
749 | return false; |
750 | } |
751 | } |
752 | return true; |
753 | } |
754 | #endif /* UNUSED */ |
755 | |
756 | FLAC__bool FLAC__bitwriter_write_utf8_uint32(FLAC__BitWriter *bw, FLAC__uint32 val) |
757 | { |
758 | FLAC__bool ok = 1; |
759 | |
760 | FLAC__ASSERT(0 != bw); |
761 | FLAC__ASSERT(0 != bw->buffer); |
762 | |
763 | if((val & 0x80000000) != 0) /* this version only handles 31 bits */ |
764 | return false; |
765 | |
766 | if(val < 0x80) { |
767 | return FLAC__bitwriter_write_raw_uint32_nocheck(bw, val, 8); |
768 | } |
769 | else if(val < 0x800) { |
770 | ok &= FLAC__bitwriter_write_raw_uint32_nocheck(bw, 0xC0 | (val>>6), 8); |
771 | ok &= FLAC__bitwriter_write_raw_uint32_nocheck(bw, 0x80 | (val&0x3F), 8); |
772 | } |
773 | else if(val < 0x10000) { |
774 | ok &= FLAC__bitwriter_write_raw_uint32_nocheck(bw, 0xE0 | (val>>12), 8); |
775 | ok &= FLAC__bitwriter_write_raw_uint32_nocheck(bw, 0x80 | ((val>>6)&0x3F), 8); |
776 | ok &= FLAC__bitwriter_write_raw_uint32_nocheck(bw, 0x80 | (val&0x3F), 8); |
777 | } |
778 | else if(val < 0x200000) { |
779 | ok &= FLAC__bitwriter_write_raw_uint32_nocheck(bw, 0xF0 | (val>>18), 8); |
780 | ok &= FLAC__bitwriter_write_raw_uint32_nocheck(bw, 0x80 | ((val>>12)&0x3F), 8); |
781 | ok &= FLAC__bitwriter_write_raw_uint32_nocheck(bw, 0x80 | ((val>>6)&0x3F), 8); |
782 | ok &= FLAC__bitwriter_write_raw_uint32_nocheck(bw, 0x80 | (val&0x3F), 8); |
783 | } |
784 | else if(val < 0x4000000) { |
785 | ok &= FLAC__bitwriter_write_raw_uint32_nocheck(bw, 0xF8 | (val>>24), 8); |
786 | ok &= FLAC__bitwriter_write_raw_uint32_nocheck(bw, 0x80 | ((val>>18)&0x3F), 8); |
787 | ok &= FLAC__bitwriter_write_raw_uint32_nocheck(bw, 0x80 | ((val>>12)&0x3F), 8); |
788 | ok &= FLAC__bitwriter_write_raw_uint32_nocheck(bw, 0x80 | ((val>>6)&0x3F), 8); |
789 | ok &= FLAC__bitwriter_write_raw_uint32_nocheck(bw, 0x80 | (val&0x3F), 8); |
790 | } |
791 | else { |
792 | ok &= FLAC__bitwriter_write_raw_uint32_nocheck(bw, 0xFC | (val>>30), 8); |
793 | ok &= FLAC__bitwriter_write_raw_uint32_nocheck(bw, 0x80 | ((val>>24)&0x3F), 8); |
794 | ok &= FLAC__bitwriter_write_raw_uint32_nocheck(bw, 0x80 | ((val>>18)&0x3F), 8); |
795 | ok &= FLAC__bitwriter_write_raw_uint32_nocheck(bw, 0x80 | ((val>>12)&0x3F), 8); |
796 | ok &= FLAC__bitwriter_write_raw_uint32_nocheck(bw, 0x80 | ((val>>6)&0x3F), 8); |
797 | ok &= FLAC__bitwriter_write_raw_uint32_nocheck(bw, 0x80 | (val&0x3F), 8); |
798 | } |
799 | |
800 | return ok; |
801 | } |
802 | |
803 | FLAC__bool FLAC__bitwriter_write_utf8_uint64(FLAC__BitWriter *bw, FLAC__uint64 val) |
804 | { |
805 | FLAC__bool ok = 1; |
806 | |
807 | FLAC__ASSERT(0 != bw); |
808 | FLAC__ASSERT(0 != bw->buffer); |
809 | |
810 | if((val & FLAC__U64L(0xFFFFFFF000000000)) != 0) /* this version only handles 36 bits */ |
811 | return false; |
812 | |
813 | if(val < 0x80) { |
814 | return FLAC__bitwriter_write_raw_uint32_nocheck(bw, (FLAC__uint32)val, 8); |
815 | } |
816 | else if(val < 0x800) { |
817 | ok &= FLAC__bitwriter_write_raw_uint32_nocheck(bw, 0xC0 | (FLAC__uint32)(val>>6), 8); |
818 | ok &= FLAC__bitwriter_write_raw_uint32_nocheck(bw, 0x80 | (FLAC__uint32)(val&0x3F), 8); |
819 | } |
820 | else if(val < 0x10000) { |
821 | ok &= FLAC__bitwriter_write_raw_uint32_nocheck(bw, 0xE0 | (FLAC__uint32)(val>>12), 8); |
822 | ok &= FLAC__bitwriter_write_raw_uint32_nocheck(bw, 0x80 | (FLAC__uint32)((val>>6)&0x3F), 8); |
823 | ok &= FLAC__bitwriter_write_raw_uint32_nocheck(bw, 0x80 | (FLAC__uint32)(val&0x3F), 8); |
824 | } |
825 | else if(val < 0x200000) { |
826 | ok &= FLAC__bitwriter_write_raw_uint32_nocheck(bw, 0xF0 | (FLAC__uint32)(val>>18), 8); |
827 | ok &= FLAC__bitwriter_write_raw_uint32_nocheck(bw, 0x80 | (FLAC__uint32)((val>>12)&0x3F), 8); |
828 | ok &= FLAC__bitwriter_write_raw_uint32_nocheck(bw, 0x80 | (FLAC__uint32)((val>>6)&0x3F), 8); |
829 | ok &= FLAC__bitwriter_write_raw_uint32_nocheck(bw, 0x80 | (FLAC__uint32)(val&0x3F), 8); |
830 | } |
831 | else if(val < 0x4000000) { |
832 | ok &= FLAC__bitwriter_write_raw_uint32_nocheck(bw, 0xF8 | (FLAC__uint32)(val>>24), 8); |
833 | ok &= FLAC__bitwriter_write_raw_uint32_nocheck(bw, 0x80 | (FLAC__uint32)((val>>18)&0x3F), 8); |
834 | ok &= FLAC__bitwriter_write_raw_uint32_nocheck(bw, 0x80 | (FLAC__uint32)((val>>12)&0x3F), 8); |
835 | ok &= FLAC__bitwriter_write_raw_uint32_nocheck(bw, 0x80 | (FLAC__uint32)((val>>6)&0x3F), 8); |
836 | ok &= FLAC__bitwriter_write_raw_uint32_nocheck(bw, 0x80 | (FLAC__uint32)(val&0x3F), 8); |
837 | } |
838 | else if(val < 0x80000000) { |
839 | ok &= FLAC__bitwriter_write_raw_uint32_nocheck(bw, 0xFC | (FLAC__uint32)(val>>30), 8); |
840 | ok &= FLAC__bitwriter_write_raw_uint32_nocheck(bw, 0x80 | (FLAC__uint32)((val>>24)&0x3F), 8); |
841 | ok &= FLAC__bitwriter_write_raw_uint32_nocheck(bw, 0x80 | (FLAC__uint32)((val>>18)&0x3F), 8); |
842 | ok &= FLAC__bitwriter_write_raw_uint32_nocheck(bw, 0x80 | (FLAC__uint32)((val>>12)&0x3F), 8); |
843 | ok &= FLAC__bitwriter_write_raw_uint32_nocheck(bw, 0x80 | (FLAC__uint32)((val>>6)&0x3F), 8); |
844 | ok &= FLAC__bitwriter_write_raw_uint32_nocheck(bw, 0x80 | (FLAC__uint32)(val&0x3F), 8); |
845 | } |
846 | else { |
847 | ok &= FLAC__bitwriter_write_raw_uint32_nocheck(bw, 0xFE, 8); |
848 | ok &= FLAC__bitwriter_write_raw_uint32_nocheck(bw, 0x80 | (FLAC__uint32)((val>>30)&0x3F), 8); |
849 | ok &= FLAC__bitwriter_write_raw_uint32_nocheck(bw, 0x80 | (FLAC__uint32)((val>>24)&0x3F), 8); |
850 | ok &= FLAC__bitwriter_write_raw_uint32_nocheck(bw, 0x80 | (FLAC__uint32)((val>>18)&0x3F), 8); |
851 | ok &= FLAC__bitwriter_write_raw_uint32_nocheck(bw, 0x80 | (FLAC__uint32)((val>>12)&0x3F), 8); |
852 | ok &= FLAC__bitwriter_write_raw_uint32_nocheck(bw, 0x80 | (FLAC__uint32)((val>>6)&0x3F), 8); |
853 | ok &= FLAC__bitwriter_write_raw_uint32_nocheck(bw, 0x80 | (FLAC__uint32)(val&0x3F), 8); |
854 | } |
855 | |
856 | return ok; |
857 | } |
858 | |
859 | FLAC__bool FLAC__bitwriter_zero_pad_to_byte_boundary(FLAC__BitWriter *bw) |
860 | { |
861 | /* 0-pad to byte boundary */ |
862 | if(bw->bits & 7u) |
863 | return FLAC__bitwriter_write_zeroes(bw, 8 - (bw->bits & 7u)); |
864 | else |
865 | return true; |
866 | } |
867 | |
868 | /* These functions are declared inline in this file but are also callable as |
869 | * externs from elsewhere. |
870 | * According to the C99 spec, section 6.7.4, simply providing a function |
871 | * prototype in a header file without 'inline' and making the function inline |
872 | * in this file should be sufficient. |
873 | * Unfortunately, the Microsoft VS compiler doesn't pick them up externally. To |
874 | * fix that we add extern declarations here. |
875 | */ |
876 | extern FLAC__bool FLAC__bitwriter_write_zeroes(FLAC__BitWriter *bw, unsigned bits); |
877 | extern FLAC__bool FLAC__bitwriter_write_raw_uint32(FLAC__BitWriter *bw, FLAC__uint32 val, unsigned bits); |
878 | extern FLAC__bool FLAC__bitwriter_write_raw_int32(FLAC__BitWriter *bw, FLAC__int32 val, unsigned bits); |
879 | extern FLAC__bool FLAC__bitwriter_write_raw_uint64(FLAC__BitWriter *bw, FLAC__uint64 val, unsigned bits); |
880 | extern FLAC__bool FLAC__bitwriter_write_raw_uint32_little_endian(FLAC__BitWriter *bw, FLAC__uint32 val); |
881 | extern FLAC__bool FLAC__bitwriter_write_byte_block(FLAC__BitWriter *bw, const FLAC__byte vals[], unsigned nvals); |