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Diffstat (limited to 'apps/codecs/libtta/ttadec.c')
-rw-r--r-- | apps/codecs/libtta/ttadec.c | 576 |
1 files changed, 576 insertions, 0 deletions
diff --git a/apps/codecs/libtta/ttadec.c b/apps/codecs/libtta/ttadec.c new file mode 100644 index 0000000000..027b78a17e --- /dev/null +++ b/apps/codecs/libtta/ttadec.c | |||
@@ -0,0 +1,576 @@ | |||
1 | /* | ||
2 | * ttadec.c | ||
3 | * | ||
4 | * Description: TTAv1 decoder library for HW players | ||
5 | * Developed by: Alexander Djourik <ald@true-audio.com> | ||
6 | * Pavel Zhilin <pzh@true-audio.com> | ||
7 | * | ||
8 | * Copyright (c) 2004 True Audio Software. All rights reserved. | ||
9 | * | ||
10 | */ | ||
11 | |||
12 | /* | ||
13 | * Redistribution and use in source and binary forms, with or without | ||
14 | * modification, are permitted provided that the following conditions | ||
15 | * are met: | ||
16 | * | ||
17 | * 1. Redistributions of source code must retain the above copyright | ||
18 | * notice, this list of conditions and the following disclaimer. | ||
19 | * 2. Redistributions in binary form must reproduce the above copyright | ||
20 | * notice, this list of conditions and the following disclaimer in the | ||
21 | * documentation and/or other materials provided with the distribution. | ||
22 | * 3. Neither the name of the True Audio Software nor the names of its | ||
23 | * contributors may be used to endorse or promote products derived | ||
24 | * from this software without specific prior written permission. | ||
25 | * | ||
26 | * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS | ||
27 | * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT | ||
28 | * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR | ||
29 | * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT | ||
30 | * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, | ||
31 | * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT | ||
32 | * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, | ||
33 | * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY | ||
34 | * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT | ||
35 | * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE | ||
36 | * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. | ||
37 | */ | ||
38 | |||
39 | #include "codeclib.h" | ||
40 | |||
41 | #include "ttalib.h" | ||
42 | #include "ttadec.h" | ||
43 | #include "filter.h" | ||
44 | |||
45 | /******************* static variables and structures *******************/ | ||
46 | |||
47 | static unsigned char isobuffers[ISO_BUFFERS_SIZE + 4] IBSS_ATTR; | ||
48 | static unsigned char *iso_buffers_end = isobuffers + ISO_BUFFERS_SIZE; | ||
49 | static unsigned int pcm_buffer_size; | ||
50 | |||
51 | static decoder tta[MAX_NCH]; /* decoder state */ | ||
52 | /* Rockbox speciffic: cache is defined in get_samples() (non static value) */ | ||
53 | /* static int cache[MAX_NCH]; // decoder cache */ | ||
54 | |||
55 | tta_info *ttainfo; /* currently playing file info */ | ||
56 | |||
57 | static unsigned int fframes; /* number of frames in file */ | ||
58 | static unsigned int framelen; /* the frame length in samples */ | ||
59 | static unsigned int lastlen; /* the length of the last frame in samples */ | ||
60 | static unsigned int data_pos; /* currently playing frame index */ | ||
61 | static unsigned int data_cur; /* the playing position in frame */ | ||
62 | |||
63 | static int maxvalue; /* output data max value */ | ||
64 | |||
65 | /* Rockbox speciffic: seek_table is static size */ | ||
66 | static unsigned int seek_table[MAX_SEEK_TABLE_SIZE]; /* the playing position table */ | ||
67 | static unsigned int st_state; /* seek table status */ | ||
68 | |||
69 | static unsigned int frame_crc32; | ||
70 | static unsigned int bit_count; | ||
71 | static unsigned int bit_cache; | ||
72 | static unsigned char *bitpos; | ||
73 | |||
74 | /* Rockbox speciffic: deletes read_id3_tags(). */ | ||
75 | /* static int read_id3_tags (tta_info *info); */ | ||
76 | |||
77 | /********************* rockbox helper functions *************************/ | ||
78 | |||
79 | /* emulate stdio functions */ | ||
80 | static int fread(void *ptr, size_t size, size_t nobj) | ||
81 | { | ||
82 | size_t read_size; | ||
83 | unsigned char *buffer = ci->request_buffer(&read_size, size * nobj); | ||
84 | |||
85 | if (read_size > 0) | ||
86 | { | ||
87 | ci->memcpy(ptr, buffer, read_size); | ||
88 | ci->advance_buffer(read_size); | ||
89 | } | ||
90 | return read_size; | ||
91 | } | ||
92 | |||
93 | static int fseek(long offset, int origin) | ||
94 | { | ||
95 | switch (origin) | ||
96 | { | ||
97 | case SEEK_CUR: | ||
98 | ci->advance_buffer(offset); | ||
99 | break; | ||
100 | case SEEK_SET: | ||
101 | ci->seek_buffer(offset); | ||
102 | break; | ||
103 | case SEEK_END: | ||
104 | ci->seek_buffer(offset + ci->id3->filesize); | ||
105 | break; | ||
106 | default: | ||
107 | return -1; | ||
108 | } | ||
109 | return 0; | ||
110 | } | ||
111 | |||
112 | /************************* crc32 functions *****************************/ | ||
113 | |||
114 | #define UPDATE_CRC32(x, crc) crc = \ | ||
115 | (((crc>>8) & 0x00FFFFFF) ^ crc32_table[(crc^x) & 0xFF]) | ||
116 | |||
117 | static unsigned int | ||
118 | crc32 (unsigned char *buffer, unsigned int len) { | ||
119 | unsigned int i; | ||
120 | unsigned int crc = 0xFFFFFFFF; | ||
121 | |||
122 | for (i = 0; i < len; i++) UPDATE_CRC32(buffer[i], crc); | ||
123 | |||
124 | return (crc ^ 0xFFFFFFFF); | ||
125 | } | ||
126 | |||
127 | /************************* bit operations ******************************/ | ||
128 | |||
129 | #define GET_BINARY(value, bits) \ | ||
130 | while (bit_count < bits) { \ | ||
131 | if (bitpos == iso_buffers_end) { \ | ||
132 | if (!fread(isobuffers, 1, ISO_BUFFERS_SIZE)) { \ | ||
133 | ttainfo->STATE = READ_ERROR; \ | ||
134 | return -1; \ | ||
135 | } \ | ||
136 | bitpos = isobuffers; \ | ||
137 | } \ | ||
138 | UPDATE_CRC32(*bitpos, frame_crc32); \ | ||
139 | bit_cache |= *bitpos << bit_count; \ | ||
140 | bit_count += 8; \ | ||
141 | bitpos++; \ | ||
142 | } \ | ||
143 | value = bit_cache & bit_mask[bits]; \ | ||
144 | bit_cache >>= bits; \ | ||
145 | bit_count -= bits; \ | ||
146 | bit_cache &= bit_mask[bit_count]; | ||
147 | |||
148 | #define GET_UNARY(value) \ | ||
149 | value = 0; \ | ||
150 | while (!(bit_cache ^ bit_mask[bit_count])) { \ | ||
151 | if (bitpos == iso_buffers_end) { \ | ||
152 | if (!fread(isobuffers, 1, ISO_BUFFERS_SIZE)) { \ | ||
153 | ttainfo->STATE = READ_ERROR; \ | ||
154 | return -1; \ | ||
155 | } \ | ||
156 | bitpos = isobuffers; \ | ||
157 | } \ | ||
158 | value += bit_count; \ | ||
159 | bit_cache = *bitpos++; \ | ||
160 | UPDATE_CRC32(bit_cache, frame_crc32); \ | ||
161 | bit_count = 8; \ | ||
162 | } \ | ||
163 | while (bit_cache & 1) { \ | ||
164 | value++; \ | ||
165 | bit_cache >>= 1; \ | ||
166 | bit_count--; \ | ||
167 | } \ | ||
168 | bit_cache >>= 1; \ | ||
169 | bit_count--; | ||
170 | |||
171 | /************************* rice operations ******************************/ | ||
172 | |||
173 | static inline int update_rice(int value, adapt *rice, int depth, | ||
174 | const unsigned int *shift_table) | ||
175 | { | ||
176 | if (depth > 0) | ||
177 | { | ||
178 | rice->sum1 += value - (rice->sum1 >> 4); | ||
179 | if (rice->k1 > 0 && rice->sum1 < shift_table[rice->k1]) | ||
180 | rice->k1--; | ||
181 | else if (rice->sum1 > shift_table[rice->k1 + 1]) | ||
182 | rice->k1++; | ||
183 | value += *(shift_table + rice->k0 - 4); | ||
184 | } | ||
185 | rice->sum0 += value - (rice->sum0 >> 4); | ||
186 | if (rice->k0 > 0 && rice->sum0 < shift_table[rice->k0]) | ||
187 | rice->k0--; | ||
188 | else if (rice->sum0 > shift_table[rice->k0 + 1]) | ||
189 | rice->k0++; | ||
190 | |||
191 | return DEC(value); | ||
192 | } | ||
193 | |||
194 | /************************* buffer functions ******************************/ | ||
195 | |||
196 | static void init_buffer_read(void) { | ||
197 | frame_crc32 = 0xFFFFFFFFUL; | ||
198 | bit_count = bit_cache = 0; | ||
199 | bitpos = iso_buffers_end; | ||
200 | } | ||
201 | |||
202 | static int done_buffer_read(void) { | ||
203 | unsigned int crc32, rbytes; | ||
204 | |||
205 | frame_crc32 ^= 0xFFFFFFFFUL; | ||
206 | rbytes = iso_buffers_end - bitpos; | ||
207 | |||
208 | if (rbytes < sizeof(int)) { | ||
209 | ci->memcpy(isobuffers, bitpos, 4); | ||
210 | if (!fread(isobuffers + rbytes, 1, ISO_BUFFERS_SIZE - rbytes)) | ||
211 | return -1; | ||
212 | bitpos = isobuffers; | ||
213 | } | ||
214 | |||
215 | ci->memcpy(&crc32, bitpos, 4); | ||
216 | crc32 = ENDSWAP_INT32(crc32); | ||
217 | bitpos += sizeof(int); | ||
218 | |||
219 | if (crc32 != frame_crc32) return -1; | ||
220 | |||
221 | bit_cache = bit_count = 0; | ||
222 | frame_crc32 = 0xFFFFFFFFUL; | ||
223 | |||
224 | return 0; | ||
225 | } | ||
226 | |||
227 | /************************* decoder functions ****************************/ | ||
228 | |||
229 | const char *get_error_str (int error) { | ||
230 | switch (error) { | ||
231 | case NO_ERROR: return "No errors found"; | ||
232 | case OPEN_ERROR: return "Can't open file"; | ||
233 | case FORMAT_ERROR: return "Not supported file format"; | ||
234 | case FILE_ERROR: return "File is corrupted"; | ||
235 | case READ_ERROR: return "Can't read from file"; | ||
236 | case MEMORY_ERROR: return "Insufficient memory available"; | ||
237 | default: return "Unknown error code"; | ||
238 | } | ||
239 | } | ||
240 | |||
241 | int set_tta_info (tta_info *info) | ||
242 | { | ||
243 | unsigned int checksum; | ||
244 | unsigned int datasize; | ||
245 | unsigned int origsize; | ||
246 | tta_hdr ttahdr; | ||
247 | |||
248 | /* clear the memory */ | ||
249 | ci->memset (info, 0, sizeof(tta_info)); | ||
250 | |||
251 | /* skip id3v2 tags */ | ||
252 | fseek(ci->id3->id3v2len, SEEK_SET); | ||
253 | |||
254 | /* read TTA header */ | ||
255 | if (fread (&ttahdr, 1, sizeof (ttahdr)) == 0) { | ||
256 | info->STATE = READ_ERROR; | ||
257 | return -1; | ||
258 | } | ||
259 | |||
260 | /* check for TTA3 signature */ | ||
261 | if (ENDSWAP_INT32(ttahdr.TTAid) != TTA1_SIGN) { | ||
262 | DEBUGF("ID error: %x\n", ENDSWAP_INT32(ttahdr.TTAid)); | ||
263 | info->STATE = FORMAT_ERROR; | ||
264 | return -1; | ||
265 | } | ||
266 | |||
267 | ttahdr.CRC32 = ENDSWAP_INT32(ttahdr.CRC32); | ||
268 | checksum = crc32((unsigned char *) &ttahdr, | ||
269 | sizeof(tta_hdr) - sizeof(int)); | ||
270 | if (checksum != ttahdr.CRC32) { | ||
271 | DEBUGF("CRC error: %x != %x\n", ttahdr.CRC32, checksum); | ||
272 | info->STATE = FILE_ERROR; | ||
273 | return -1; | ||
274 | } | ||
275 | |||
276 | ttahdr.AudioFormat = ENDSWAP_INT16(ttahdr.AudioFormat); | ||
277 | ttahdr.NumChannels = ENDSWAP_INT16(ttahdr.NumChannels); | ||
278 | ttahdr.BitsPerSample = ENDSWAP_INT16(ttahdr.BitsPerSample); | ||
279 | ttahdr.SampleRate = ENDSWAP_INT32(ttahdr.SampleRate); | ||
280 | ttahdr.DataLength = ENDSWAP_INT32(ttahdr.DataLength); | ||
281 | |||
282 | /* check for player supported formats */ | ||
283 | if (ttahdr.AudioFormat != WAVE_FORMAT_PCM || | ||
284 | ttahdr.NumChannels > MAX_NCH || | ||
285 | ttahdr.BitsPerSample > MAX_BPS ||( | ||
286 | ttahdr.SampleRate != 16000 && | ||
287 | ttahdr.SampleRate != 22050 && | ||
288 | ttahdr.SampleRate != 24000 && | ||
289 | ttahdr.SampleRate != 32000 && | ||
290 | ttahdr.SampleRate != 44100 && | ||
291 | ttahdr.SampleRate != 48000 && | ||
292 | ttahdr.SampleRate != 64000 && | ||
293 | ttahdr.SampleRate != 88200 && | ||
294 | ttahdr.SampleRate != 96000)) { | ||
295 | info->STATE = FORMAT_ERROR; | ||
296 | DEBUGF("illegal audio format: %d channels: %d samplerate: %d\n", | ||
297 | ttahdr.AudioFormat, ttahdr.NumChannels, ttahdr.SampleRate); | ||
298 | return -1; | ||
299 | } | ||
300 | |||
301 | /* fill the File Info */ | ||
302 | info->NCH = ttahdr.NumChannels; | ||
303 | info->BPS = ttahdr.BitsPerSample; | ||
304 | info->BSIZE = (ttahdr.BitsPerSample + 7)/8; | ||
305 | info->FORMAT = ttahdr.AudioFormat; | ||
306 | info->SAMPLERATE = ttahdr.SampleRate; | ||
307 | info->DATALENGTH = ttahdr.DataLength; | ||
308 | info->FRAMELEN = (int) MULTIPLY_FRAME_TIME(ttahdr.SampleRate); | ||
309 | info->LENGTH = ttahdr.DataLength / ttahdr.SampleRate; | ||
310 | info->DATAPOS = ci->id3->id3v2len; | ||
311 | info->FILESIZE = ci->id3->filesize; | ||
312 | |||
313 | datasize = info->FILESIZE - info->DATAPOS; | ||
314 | origsize = info->DATALENGTH * info->BSIZE * info->NCH; | ||
315 | |||
316 | /* info->COMPRESS = (double) datasize / origsize; */ | ||
317 | info->BITRATE = (int) ((uint64_t) datasize * info->SAMPLERATE * info->NCH * info->BPS | ||
318 | / (origsize * 1000LL)); | ||
319 | |||
320 | return 0; | ||
321 | } | ||
322 | |||
323 | static void rice_init(adapt *rice, unsigned int k0, unsigned int k1) { | ||
324 | rice->k0 = k0; | ||
325 | rice->k1 = k1; | ||
326 | rice->sum0 = shift_16[k0]; | ||
327 | rice->sum1 = shift_16[k1]; | ||
328 | } | ||
329 | |||
330 | static void decoder_init(decoder *tta, int nch, int byte_size) { | ||
331 | int shift = flt_set[byte_size - 1]; | ||
332 | int i; | ||
333 | |||
334 | for (i = 0; i < nch; i++) { | ||
335 | filter_init(&tta[i].fst, shift); | ||
336 | rice_init(&tta[i].rice, 10, 10); | ||
337 | tta[i].last = 0; | ||
338 | } | ||
339 | } | ||
340 | |||
341 | static void seek_table_init (unsigned int *seek_table, | ||
342 | unsigned int len, unsigned int data_offset) { | ||
343 | unsigned int *st, frame_len; | ||
344 | |||
345 | for (st = seek_table; st < (seek_table + len); st++) { | ||
346 | frame_len = ENDSWAP_INT32(*st); | ||
347 | *st = data_offset; | ||
348 | data_offset += frame_len; | ||
349 | } | ||
350 | } | ||
351 | |||
352 | int set_position (unsigned int pos, enum tta_seek_type type) | ||
353 | { | ||
354 | unsigned int i; | ||
355 | unsigned int seek_pos; | ||
356 | |||
357 | if (type == TTA_SEEK_TIME) | ||
358 | { | ||
359 | if (pos >= fframes) | ||
360 | pos = fframes -1; | ||
361 | } | ||
362 | else | ||
363 | { | ||
364 | pos -= ttainfo->DATAPOS; | ||
365 | for (i = 1; i < fframes; i++) | ||
366 | { | ||
367 | if (seek_table[i] > pos) | ||
368 | break; | ||
369 | } | ||
370 | pos = i - 1; | ||
371 | } | ||
372 | if (!st_state) { | ||
373 | ttainfo->STATE = FILE_ERROR; | ||
374 | return -1; | ||
375 | } | ||
376 | seek_pos = ttainfo->DATAPOS + seek_table[data_pos = pos]; | ||
377 | if (fseek(seek_pos, SEEK_SET) < 0) { | ||
378 | ttainfo->STATE = READ_ERROR; | ||
379 | return -1; | ||
380 | } | ||
381 | |||
382 | data_cur = 0; | ||
383 | framelen = 0; | ||
384 | |||
385 | /* init bit reader */ | ||
386 | init_buffer_read(); | ||
387 | return data_pos * ttainfo->FRAMELEN; | ||
388 | } | ||
389 | |||
390 | int player_init (tta_info *info) { | ||
391 | unsigned int checksum; | ||
392 | unsigned int data_offset; | ||
393 | unsigned int st_size; | ||
394 | |||
395 | ttainfo = info; | ||
396 | |||
397 | framelen = 0; | ||
398 | data_pos = 0; | ||
399 | data_cur = 0; | ||
400 | |||
401 | lastlen = ttainfo->DATALENGTH % ttainfo->FRAMELEN; | ||
402 | fframes = ttainfo->DATALENGTH / ttainfo->FRAMELEN + (lastlen ? 1 : 0); | ||
403 | st_size = (fframes + 1) * sizeof(int); | ||
404 | |||
405 | /* | ||
406 | * Rockbox speciffic | ||
407 | * playable tta file is to MAX_SEEK_TABLE_SIZE frames | ||
408 | * about 1:08:15 (frequency 44.1 kHz) | ||
409 | */ | ||
410 | if (fframes > MAX_SEEK_TABLE_SIZE) | ||
411 | { | ||
412 | LOGF("frame is too many: %d > %d", fframes, MAX_SEEK_TABLE_SIZE); | ||
413 | return -1; | ||
414 | } | ||
415 | |||
416 | /* read seek table */ | ||
417 | if (!fread(seek_table, st_size, 1)) { | ||
418 | ttainfo->STATE = READ_ERROR; | ||
419 | return -1; | ||
420 | } | ||
421 | |||
422 | checksum = crc32((unsigned char *) seek_table, st_size - sizeof(int)); | ||
423 | st_state = (checksum == ENDSWAP_INT32(seek_table[fframes])); | ||
424 | data_offset = sizeof(tta_hdr) + st_size; | ||
425 | |||
426 | /* init seek table */ | ||
427 | seek_table_init(seek_table, fframes, data_offset); | ||
428 | |||
429 | /* init bit reader */ | ||
430 | init_buffer_read(); | ||
431 | |||
432 | /* | ||
433 | * Rockbox speciffic | ||
434 | * because pcm data is int32_t, does not multiply ttainfo->BSIZE. | ||
435 | */ | ||
436 | pcm_buffer_size = PCM_BUFFER_LENGTH * ttainfo->NCH; | ||
437 | maxvalue = (1UL << ttainfo->BPS) - 1; | ||
438 | |||
439 | return 0; | ||
440 | } | ||
441 | |||
442 | /* | ||
443 | * Rockbox specffic | ||
444 | * because the seek table is static size buffer, player_stop() is nooperation function. | ||
445 | */ | ||
446 | void player_stop (void) { | ||
447 | /* | ||
448 | if (seek_table) { | ||
449 | free(seek_table); | ||
450 | seek_table = NULL; | ||
451 | } | ||
452 | */ | ||
453 | } | ||
454 | |||
455 | /* | ||
456 | * Rockbox speciffic | ||
457 | * with the optimization, the decoding logic is modify a little. | ||
458 | */ | ||
459 | int get_samples (int32_t *buffer) { | ||
460 | unsigned int k, depth, unary, binary; | ||
461 | int32_t *p = buffer; | ||
462 | decoder *dec = tta; | ||
463 | int value, res; | ||
464 | int cur_pos = pcm_buffer_size; | ||
465 | int pcm_shift_bits = TTA_OUTPUT_DEPTH - ttainfo->BPS; | ||
466 | int pr_bits = (ttainfo->BSIZE == 1)? 4 : 5; | ||
467 | int cache = 0; /* decoder cache */ | ||
468 | |||
469 | fltst *fst; | ||
470 | adapt *rice; | ||
471 | |||
472 | for (res = 0; --cur_pos >= 0;) { | ||
473 | fst = &dec->fst; | ||
474 | rice = &dec->rice; | ||
475 | |||
476 | if (data_cur == framelen) { | ||
477 | if (data_pos == fframes) break; | ||
478 | if (framelen && done_buffer_read()) { | ||
479 | if (set_position(data_pos, TTA_SEEK_TIME) < 0) return -1; | ||
480 | if (res) break; | ||
481 | } | ||
482 | |||
483 | if (data_pos == fframes - 1 && lastlen) | ||
484 | framelen = lastlen; | ||
485 | else framelen = ttainfo->FRAMELEN; | ||
486 | |||
487 | decoder_init(tta, ttainfo->NCH, ttainfo->BSIZE); | ||
488 | data_pos++; data_cur = 0; | ||
489 | } | ||
490 | |||
491 | /* decode Rice unsigned */ | ||
492 | GET_UNARY(unary); | ||
493 | |||
494 | switch (unary) { | ||
495 | case 0: depth = 0; k = rice->k0; break; | ||
496 | default: | ||
497 | depth = 1; k = rice->k1; | ||
498 | unary--; | ||
499 | } | ||
500 | |||
501 | if (k) { | ||
502 | GET_BINARY(binary, k); | ||
503 | value = (unary << k) + binary; | ||
504 | } else value = unary; | ||
505 | |||
506 | value = update_rice(value, rice, depth, shift_16); | ||
507 | |||
508 | /* Rockbox specific: the following logic move to update_rice() */ | ||
509 | #if 0 | ||
510 | if (depth > 0) | ||
511 | { | ||
512 | rice->sum1 += value - (rice->sum1 >> 4); | ||
513 | if (rice->k1 > 0 && rice->sum1 < shift_16[rice->k1]) | ||
514 | rice->k1--; | ||
515 | else if (rice->sum1 > shift_16[rice->k1 + 1]) | ||
516 | rice->k1++; | ||
517 | value += bit_shift[rice->k0]; | ||
518 | } | ||
519 | rice->sum0 += value - (rice->sum0 >> 4); | ||
520 | if (rice->k0 > 0 && rice->sum0 < shift_16[rice->k0]) | ||
521 | rice->k0--; | ||
522 | else if (rice->sum0 > shift_16[rice->k0 + 1]) | ||
523 | rice->k0++; | ||
524 | |||
525 | value = DEC(value); | ||
526 | #endif | ||
527 | |||
528 | /* decompress stage 1: adaptive hybrid filter */ | ||
529 | hybrid_filter(fst, &value); | ||
530 | |||
531 | /* decompress stage 2: fixed order 1 prediction */ | ||
532 | value += PREDICTOR1(dec->last, pr_bits); | ||
533 | dec->last = value; | ||
534 | |||
535 | /* check for errors */ | ||
536 | if (abs(value) > maxvalue) { | ||
537 | unsigned int tail = | ||
538 | pcm_buffer_size / (ttainfo->BSIZE * ttainfo->NCH) - res; | ||
539 | ci->memset(buffer, 0, pcm_buffer_size * sizeof(int32_t)); | ||
540 | data_cur += tail; res += tail; | ||
541 | break; | ||
542 | } | ||
543 | |||
544 | /* Rockbox speciffic: Rockbox supports max 2channels */ | ||
545 | if (ttainfo->NCH == 1) | ||
546 | { | ||
547 | *p++ = value << pcm_shift_bits; | ||
548 | data_cur++; | ||
549 | res++; | ||
550 | } | ||
551 | else | ||
552 | { | ||
553 | if (dec == tta) | ||
554 | { | ||
555 | cache = value; | ||
556 | dec++; | ||
557 | } | ||
558 | else | ||
559 | { | ||
560 | value += cache / 2; | ||
561 | cache = value - cache; | ||
562 | dec = tta; | ||
563 | *p++ = cache << pcm_shift_bits; | ||
564 | *p++ = value << pcm_shift_bits; | ||
565 | data_cur++; | ||
566 | res++; | ||
567 | } | ||
568 | } | ||
569 | } | ||
570 | |||
571 | return res; | ||
572 | } | ||
573 | |||
574 | /* Rockbox speciffic: id3 tags functions delete. */ | ||
575 | |||
576 | /* eof */ | ||