Fix up configure and buildzip/wpsbuild.pl a bit
[kugel-rb.git] / apps / codecs / libmad / layer12.c
blobe00bb645306d30b8d298c44d2ff6efc445bff2c7
1 /*
2 * libmad - MPEG audio decoder library
3 * Copyright (C) 2000-2004 Underbit Technologies, Inc.
5 * This program is free software; you can redistribute it and/or modify
6 * it under the terms of the GNU General Public License as published by
7 * the Free Software Foundation; either version 2 of the License, or
8 * (at your option) any later version.
10 * This program is distributed in the hope that it will be useful,
11 * but WITHOUT ANY WARRANTY; without even the implied warranty of
12 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
13 * GNU General Public License for more details.
15 * You should have received a copy of the GNU General Public License
16 * along with this program; if not, write to the Free Software
17 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
19 * $Id$
22 # ifdef HAVE_CONFIG_H
23 # include "config.h"
24 # endif
26 # include "global.h"
28 # ifdef HAVE_LIMITS_H
29 # include <limits.h>
30 # else
31 # undef CHAR_BIT
32 # define CHAR_BIT 8
33 # endif
35 # include "fixed.h"
36 # include "bit.h"
37 # include "stream.h"
38 # include "frame.h"
39 # include "layer12.h"
42 * scalefactor table
43 * used in both Layer I and Layer II decoding
45 static
46 mad_fixed_t const sf_table[64] ICONST_ATTR = {
47 # include "sf_table.dat"
50 /* --- Layer I ------------------------------------------------------------- */
52 /* linear scaling table */
53 static
54 mad_fixed_t const linear_table[14] ICONST_ATTR = {
55 MAD_F(0x15555555), /* 2^2 / (2^2 - 1) == 1.33333333333333 */
56 MAD_F(0x12492492), /* 2^3 / (2^3 - 1) == 1.14285714285714 */
57 MAD_F(0x11111111), /* 2^4 / (2^4 - 1) == 1.06666666666667 */
58 MAD_F(0x10842108), /* 2^5 / (2^5 - 1) == 1.03225806451613 */
59 MAD_F(0x10410410), /* 2^6 / (2^6 - 1) == 1.01587301587302 */
60 MAD_F(0x10204081), /* 2^7 / (2^7 - 1) == 1.00787401574803 */
61 MAD_F(0x10101010), /* 2^8 / (2^8 - 1) == 1.00392156862745 */
62 MAD_F(0x10080402), /* 2^9 / (2^9 - 1) == 1.00195694716243 */
63 MAD_F(0x10040100), /* 2^10 / (2^10 - 1) == 1.00097751710655 */
64 MAD_F(0x10020040), /* 2^11 / (2^11 - 1) == 1.00048851978505 */
65 MAD_F(0x10010010), /* 2^12 / (2^12 - 1) == 1.00024420024420 */
66 MAD_F(0x10008004), /* 2^13 / (2^13 - 1) == 1.00012208521548 */
67 MAD_F(0x10004001), /* 2^14 / (2^14 - 1) == 1.00006103888177 */
68 MAD_F(0x10002000) /* 2^15 / (2^15 - 1) == 1.00003051850948 */
72 * NAME: I_sample()
73 * DESCRIPTION: decode one requantized Layer I sample from a bitstream
75 static inline
76 mad_fixed_t I_sample(struct mad_bitptr *ptr, unsigned int nb)
78 mad_fixed_t sample;
80 sample = mad_bit_read(ptr, nb);
82 /* invert most significant bit, extend sign, then scale to fixed format */
84 sample ^= 1 << (nb - 1);
85 sample |= -(sample & (1 << (nb - 1)));
87 sample <<= MAD_F_FRACBITS - (nb - 1);
89 /* requantize the sample */
91 /* s'' = (2^nb / (2^nb - 1)) * (s''' + 2^(-nb + 1)) */
93 sample += MAD_F_ONE >> (nb - 1);
95 return mad_f_mul(sample, linear_table[nb - 2]);
97 /* s' = factor * s'' */
98 /* (to be performed by caller) */
102 * NAME: layer->I()
103 * DESCRIPTION: decode a single Layer I frame
105 int mad_layer_I(struct mad_stream *stream, struct mad_frame *frame)
107 struct mad_header *header = &frame->header;
108 unsigned int nch, bound, ch, s, sb, nb;
109 unsigned char allocation[2][32], scalefactor[2][32];
111 nch = MAD_NCHANNELS(header);
113 bound = 32;
114 if (header->mode == MAD_MODE_JOINT_STEREO) {
115 header->flags |= MAD_FLAG_I_STEREO;
116 bound = 4 + header->mode_extension * 4;
119 /* check CRC word */
121 if (header->flags & MAD_FLAG_PROTECTION) {
122 header->crc_check =
123 mad_bit_crc(stream->ptr, 4 * (bound * nch + (32 - bound)),
124 header->crc_check);
126 if (header->crc_check != header->crc_target &&
127 !(frame->options & MAD_OPTION_IGNORECRC)) {
128 stream->error = MAD_ERROR_BADCRC;
129 return -1;
133 /* decode bit allocations */
135 for (sb = 0; sb < bound; ++sb) {
136 for (ch = 0; ch < nch; ++ch) {
137 nb = mad_bit_read(&stream->ptr, 4);
139 if (nb == 15) {
140 stream->error = MAD_ERROR_BADBITALLOC;
141 return -1;
144 allocation[ch][sb] = nb ? nb + 1 : 0;
148 for (sb = bound; sb < 32; ++sb) {
149 nb = mad_bit_read(&stream->ptr, 4);
151 if (nb == 15) {
152 stream->error = MAD_ERROR_BADBITALLOC;
153 return -1;
156 allocation[0][sb] =
157 allocation[1][sb] = nb ? nb + 1 : 0;
160 /* decode scalefactors */
162 for (sb = 0; sb < 32; ++sb) {
163 for (ch = 0; ch < nch; ++ch) {
164 if (allocation[ch][sb]) {
165 scalefactor[ch][sb] = mad_bit_read(&stream->ptr, 6);
167 # if defined(OPT_STRICT)
169 * Scalefactor index 63 does not appear in Table B.1 of
170 * ISO/IEC 11172-3. Nonetheless, other implementations accept it,
171 * so we only reject it if OPT_STRICT is defined.
173 if (scalefactor[ch][sb] == 63) {
174 stream->error = MAD_ERROR_BADSCALEFACTOR;
175 return -1;
177 # endif
182 /* decode samples */
184 for (s = 0; s < 12; ++s) {
185 for (sb = 0; sb < bound; ++sb) {
186 for (ch = 0; ch < nch; ++ch) {
187 nb = allocation[ch][sb];
188 (*frame->sbsample)[ch][s][sb] = nb ?
189 mad_f_mul(I_sample(&stream->ptr, nb),
190 sf_table[scalefactor[ch][sb]]) : 0;
194 for (sb = bound; sb < 32; ++sb) {
195 if ((nb = allocation[0][sb])) {
196 mad_fixed_t sample;
198 sample = I_sample(&stream->ptr, nb);
200 for (ch = 0; ch < nch; ++ch) {
201 (*frame->sbsample)[ch][s][sb] =
202 mad_f_mul(sample, sf_table[scalefactor[ch][sb]]);
205 else {
206 for (ch = 0; ch < nch; ++ch)
207 (*frame->sbsample)[ch][s][sb] = 0;
212 return 0;
215 /* --- Layer II ------------------------------------------------------------ */
217 /* possible quantization per subband table */
218 static
219 struct {
220 unsigned int sblimit;
221 unsigned char const offsets[30];
222 } const sbquant_table[5] = {
223 /* ISO/IEC 11172-3 Table B.2a */
224 { 27, { 7, 7, 7, 6, 6, 6, 6, 6, 6, 6, 6, 3, 3, 3, 3, 3, /* 0 */
225 3, 3, 3, 3, 3, 3, 3, 0, 0, 0, 0 } },
226 /* ISO/IEC 11172-3 Table B.2b */
227 { 30, { 7, 7, 7, 6, 6, 6, 6, 6, 6, 6, 6, 3, 3, 3, 3, 3, /* 1 */
228 3, 3, 3, 3, 3, 3, 3, 0, 0, 0, 0, 0, 0, 0 } },
229 /* ISO/IEC 11172-3 Table B.2c */
230 { 8, { 5, 5, 2, 2, 2, 2, 2, 2 } }, /* 2 */
231 /* ISO/IEC 11172-3 Table B.2d */
232 { 12, { 5, 5, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2 } }, /* 3 */
233 /* ISO/IEC 13818-3 Table B.1 */
234 { 30, { 4, 4, 4, 4, 2, 2, 2, 2, 2, 2, 2, 1, 1, 1, 1, 1, /* 4 */
235 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1 } }
238 /* bit allocation table */
239 static
240 struct {
241 unsigned short nbal;
242 unsigned short offset;
243 } const bitalloc_table[8] = {
244 { 2, 0 }, /* 0 */
245 { 2, 3 }, /* 1 */
246 { 3, 3 }, /* 2 */
247 { 3, 1 }, /* 3 */
248 { 4, 2 }, /* 4 */
249 { 4, 3 }, /* 5 */
250 { 4, 4 }, /* 6 */
251 { 4, 5 } /* 7 */
254 /* offsets into quantization class table */
255 static
256 unsigned char const offset_table[6][15] = {
257 { 0, 1, 16 }, /* 0 */
258 { 0, 1, 2, 3, 4, 5, 16 }, /* 1 */
259 { 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14 }, /* 2 */
260 { 0, 1, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15 }, /* 3 */
261 { 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 16 }, /* 4 */
262 { 0, 2, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16 } /* 5 */
265 /* quantization class table */
266 static
267 struct quantclass {
268 unsigned short nlevels;
269 unsigned char group;
270 unsigned char bits;
271 mad_fixed_t C;
272 mad_fixed_t D;
273 } const qc_table[17] ICONST_ATTR = {
274 # include "qc_table.dat"
278 * NAME: II_samples()
279 * DESCRIPTION: decode three requantized Layer II samples from a bitstream
281 static
282 void II_samples(struct mad_bitptr *ptr,
283 struct quantclass const *quantclass,
284 mad_fixed_t output[3])
286 unsigned int nb, s, sample[3];
288 if ((nb = quantclass->group)) {
289 unsigned int c, nlevels;
291 /* degrouping */
292 c = mad_bit_read(ptr, quantclass->bits);
293 nlevels = quantclass->nlevels;
295 for (s = 0; s < 3; ++s) {
296 sample[s] = c % nlevels;
297 c /= nlevels;
300 else {
301 nb = quantclass->bits;
303 for (s = 0; s < 3; ++s)
304 sample[s] = mad_bit_read(ptr, nb);
307 for (s = 0; s < 3; ++s) {
308 mad_fixed_t requantized;
310 /* invert most significant bit, extend sign, then scale to fixed format */
312 requantized = sample[s] ^ (1 << (nb - 1));
313 requantized |= -(requantized & (1 << (nb - 1)));
315 requantized <<= MAD_F_FRACBITS - (nb - 1);
317 /* requantize the sample */
319 /* s'' = C * (s''' + D) */
321 output[s] = mad_f_mul(requantized + quantclass->D, quantclass->C);
323 /* s' = factor * s'' */
324 /* (to be performed by caller) */
329 * NAME: layer->II()
330 * DESCRIPTION: decode a single Layer II frame
332 int mad_layer_II(struct mad_stream *stream, struct mad_frame *frame)
334 struct mad_header *header = &frame->header;
335 struct mad_bitptr start;
336 unsigned int index, sblimit, nbal, nch, bound, gr, ch, s, sb;
337 unsigned char const *offsets;
338 unsigned char allocation[2][32], scfsi[2][32], scalefactor[2][32][3];
339 mad_fixed_t samples[3];
341 nch = MAD_NCHANNELS(header);
343 if (header->flags & MAD_FLAG_LSF_EXT)
344 index = 4;
345 else if (header->flags & MAD_FLAG_FREEFORMAT)
346 goto freeformat;
347 else {
348 unsigned long bitrate_per_channel;
350 bitrate_per_channel = header->bitrate;
351 if (nch == 2) {
352 bitrate_per_channel /= 2;
354 # if defined(OPT_STRICT)
356 * ISO/IEC 11172-3 allows only single channel mode for 32, 48, 56, and
357 * 80 kbps bitrates in Layer II, but some encoders ignore this
358 * restriction. We enforce it if OPT_STRICT is defined.
360 if (bitrate_per_channel <= 28000 || bitrate_per_channel == 40000) {
361 stream->error = MAD_ERROR_BADMODE;
362 return -1;
364 # endif
366 else { /* nch == 1 */
367 if (bitrate_per_channel > 192000) {
369 * ISO/IEC 11172-3 does not allow single channel mode for 224, 256,
370 * 320, or 384 kbps bitrates in Layer II.
372 stream->error = MAD_ERROR_BADMODE;
373 return -1;
377 if (bitrate_per_channel <= 48000)
378 index = (header->samplerate == 32000) ? 3 : 2;
379 else if (bitrate_per_channel <= 80000)
380 index = 0;
381 else {
382 freeformat:
383 index = (header->samplerate == 48000) ? 0 : 1;
387 sblimit = sbquant_table[index].sblimit;
388 offsets = sbquant_table[index].offsets;
390 bound = 32;
391 if (header->mode == MAD_MODE_JOINT_STEREO) {
392 header->flags |= MAD_FLAG_I_STEREO;
393 bound = 4 + header->mode_extension * 4;
396 if (bound > sblimit)
397 bound = sblimit;
399 start = stream->ptr;
401 /* decode bit allocations */
403 for (sb = 0; sb < bound; ++sb) {
404 nbal = bitalloc_table[offsets[sb]].nbal;
406 for (ch = 0; ch < nch; ++ch)
407 allocation[ch][sb] = mad_bit_read(&stream->ptr, nbal);
410 for (sb = bound; sb < sblimit; ++sb) {
411 nbal = bitalloc_table[offsets[sb]].nbal;
413 allocation[0][sb] =
414 allocation[1][sb] = mad_bit_read(&stream->ptr, nbal);
417 /* decode scalefactor selection info */
419 for (sb = 0; sb < sblimit; ++sb) {
420 for (ch = 0; ch < nch; ++ch) {
421 if (allocation[ch][sb])
422 scfsi[ch][sb] = mad_bit_read(&stream->ptr, 2);
426 /* check CRC word */
428 if (header->flags & MAD_FLAG_PROTECTION) {
429 header->crc_check =
430 mad_bit_crc(start, mad_bit_length(&start, &stream->ptr),
431 header->crc_check);
433 if (header->crc_check != header->crc_target &&
434 !(frame->options & MAD_OPTION_IGNORECRC)) {
435 stream->error = MAD_ERROR_BADCRC;
436 return -1;
440 /* decode scalefactors */
442 for (sb = 0; sb < sblimit; ++sb) {
443 for (ch = 0; ch < nch; ++ch) {
444 if (allocation[ch][sb]) {
445 scalefactor[ch][sb][0] = mad_bit_read(&stream->ptr, 6);
447 switch (scfsi[ch][sb]) {
448 case 2:
449 scalefactor[ch][sb][2] =
450 scalefactor[ch][sb][1] =
451 scalefactor[ch][sb][0];
452 break;
454 case 0:
455 scalefactor[ch][sb][1] = mad_bit_read(&stream->ptr, 6);
456 /* fall through */
458 case 1:
459 case 3:
460 scalefactor[ch][sb][2] = mad_bit_read(&stream->ptr, 6);
463 if (scfsi[ch][sb] & 1)
464 scalefactor[ch][sb][1] = scalefactor[ch][sb][scfsi[ch][sb] - 1];
466 # if defined(OPT_STRICT)
468 * Scalefactor index 63 does not appear in Table B.1 of
469 * ISO/IEC 11172-3. Nonetheless, other implementations accept it,
470 * so we only reject it if OPT_STRICT is defined.
472 if (scalefactor[ch][sb][0] == 63 ||
473 scalefactor[ch][sb][1] == 63 ||
474 scalefactor[ch][sb][2] == 63) {
475 stream->error = MAD_ERROR_BADSCALEFACTOR;
476 return -1;
478 # endif
483 /* decode samples */
485 for (gr = 0; gr < 12; ++gr) {
486 for (sb = 0; sb < bound; ++sb) {
487 for (ch = 0; ch < nch; ++ch) {
488 if ((index = allocation[ch][sb])) {
489 int off = bitalloc_table[offsets[sb]].offset;
490 index = offset_table[off][index - 1];
492 II_samples(&stream->ptr, &qc_table[index], samples);
494 for (s = 0; s < 3; ++s) {
495 (*frame->sbsample)[ch][3 * gr + s][sb] =
496 mad_f_mul(samples[s], sf_table[scalefactor[ch][sb][gr / 4]]);
499 else {
500 for (s = 0; s < 3; ++s)
501 (*frame->sbsample)[ch][3 * gr + s][sb] = 0;
506 for (sb = bound; sb < sblimit; ++sb) {
507 if ((index = allocation[0][sb])) {
508 int off = bitalloc_table[offsets[sb]].offset;
509 index = offset_table[off][index - 1];
511 II_samples(&stream->ptr, &qc_table[index], samples);
513 for (ch = 0; ch < nch; ++ch) {
514 for (s = 0; s < 3; ++s) {
515 (*frame->sbsample)[ch][3 * gr + s][sb] =
516 mad_f_mul(samples[s], sf_table[scalefactor[ch][sb][gr / 4]]);
520 else {
521 for (ch = 0; ch < nch; ++ch) {
522 for (s = 0; s < 3; ++s)
523 (*frame->sbsample)[ch][3 * gr + s][sb] = 0;
528 for (ch = 0; ch < nch; ++ch) {
529 for (s = 0; s < 3; ++s) {
530 for (sb = sblimit; sb < 32; ++sb)
531 (*frame->sbsample)[ch][3 * gr + s][sb] = 0;
536 return 0;