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1
/*
2
 * ADPCM codecs
3
 * Copyright (c) 2001 Fabrice Bellard.
4
 *
5
 * This library is free software; you can redistribute it and/or
6
 * modify it under the terms of the GNU Lesser General Public
7
 * License as published by the Free Software Foundation; either
8
 * version 2 of the License, or (at your option) any later version.
9
 *
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 * This library 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 GNU
13
 * Lesser General Public License for more details.
14
 *
15
 * You should have received a copy of the GNU Lesser General Public
16
 * License along with this library; if not, write to the Free Software
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 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
18
 */
19
#include "avcodec.h"
20

    
21
/*
22
 * First version by Francois Revol revol@free.fr
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 *
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 * Features and limitations:
25
 *
26
 * Reference documents:
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 * http://www.pcisys.net/~melanson/codecs/adpcm.txt
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 * http://www.geocities.com/SiliconValley/8682/aud3.txt
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 * http://openquicktime.sourceforge.net/plugins.htm
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 * XAnim sources (xa_codec.c) http://www.rasnaimaging.com/people/lapus/download.html
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 * http://www.cs.ucla.edu/~leec/mediabench/applications.html
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 * SoX source code http://home.sprynet.com/~cbagwell/sox.html
33
 */
34

    
35
#define BLKSIZE 1024
36

    
37
#define CLAMP_TO_SHORT(value) \
38
if (value > 32767) \
39
    value = 32767; \
40
else if (value < -32768) \
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    value = -32768; \
42

    
43
/* step_table[] and index_table[] are from the ADPCM reference source */
44
/* This is the index table: */
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static int index_table[16] = {
46
    -1, -1, -1, -1, 2, 4, 6, 8,
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    -1, -1, -1, -1, 2, 4, 6, 8,
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};
49

    
50
/* This is the step table. Note that many programs use slight deviations from
51
 * this table, but such deviations are negligible:
52
 */
53
static int step_table[89] = {
54
    7, 8, 9, 10, 11, 12, 13, 14, 16, 17,
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    19, 21, 23, 25, 28, 31, 34, 37, 41, 45,
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    50, 55, 60, 66, 73, 80, 88, 97, 107, 118,
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    130, 143, 157, 173, 190, 209, 230, 253, 279, 307,
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    337, 371, 408, 449, 494, 544, 598, 658, 724, 796,
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    876, 963, 1060, 1166, 1282, 1411, 1552, 1707, 1878, 2066,
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    2272, 2499, 2749, 3024, 3327, 3660, 4026, 4428, 4871, 5358,
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    5894, 6484, 7132, 7845, 8630, 9493, 10442, 11487, 12635, 13899,
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    15289, 16818, 18500, 20350, 22385, 24623, 27086, 29794, 32767
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};
64

    
65
/* Those are for MS-ADPCM */
66
/* AdaptationTable[], AdaptCoeff1[], and AdaptCoeff2[] are from libsndfile */
67
static int AdaptationTable[] = {
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        230, 230, 230, 230, 307, 409, 512, 614,
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        768, 614, 512, 409, 307, 230, 230, 230
70
};
71

    
72
static int AdaptCoeff1[] = {
73
        256, 512, 0, 192, 240, 460, 392
74
};
75

    
76
static int AdaptCoeff2[] = {
77
        0, -256, 0, 64, 0, -208, -232
78
};
79

    
80
/* end of tables */
81

    
82
typedef struct ADPCMChannelStatus {
83
    int predictor;
84
    short int step_index;
85
    int step;
86
    /* for encoding */
87
    int prev_sample;
88

    
89
    /* MS version */
90
    short sample1;
91
    short sample2;
92
    int coeff1;
93
    int coeff2;
94
    int idelta;
95
} ADPCMChannelStatus;
96

    
97
typedef struct ADPCMContext {
98
    int channel; /* for stereo MOVs, decode left, then decode right, then tell it's decoded */
99
    ADPCMChannelStatus status[2];
100
    short sample_buffer[32]; /* hold left samples while waiting for right samples */
101
} ADPCMContext;
102

    
103
/* XXX: implement encoding */
104

    
105
static int adpcm_encode_init(AVCodecContext *avctx)
106
{
107
    if (avctx->channels > 2)
108
        return -1; /* only stereo or mono =) */
109
    switch(avctx->codec->id) {
110
    case CODEC_ID_ADPCM_IMA_QT:
111
        fprintf(stderr, "ADPCM: codec admcp_ima_qt unsupported for encoding !\n");
112
        avctx->frame_size = 64; /* XXX: can multiple of avctx->channels * 64 (left and right blocks are interleaved) */
113
        return -1;
114
        break;
115
    case CODEC_ID_ADPCM_IMA_WAV:
116
        avctx->frame_size = (BLKSIZE - 4 * avctx->channels) * 8 / (4 * avctx->channels) + 1; /* each 16 bits sample gives one nibble */
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                                                             /* and we have 4 bytes per channel overhead */
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        avctx->block_align = BLKSIZE;
119
        /* seems frame_size isn't taken into account... have to buffer the samples :-( */
120
        break;
121
    case CODEC_ID_ADPCM_MS:
122
        fprintf(stderr, "ADPCM: codec admcp_ms unsupported for encoding !\n");
123
        return -1;
124
        break;
125
    default:
126
        return -1;
127
        break;
128
    }
129
    return 0;
130
}
131

    
132
static int adpcm_encode_close(AVCodecContext *avctx)
133
{
134
    /* nothing to free */
135
    return 0;
136
}
137

    
138

    
139
static inline unsigned char adpcm_ima_compress_sample(ADPCMChannelStatus *c, short sample)
140
{
141
    int step_index;
142
    unsigned char nibble;
143
    
144
    int sign = 0; /* sign bit of the nibble (MSB) */
145
    int delta, predicted_delta;
146

    
147
    delta = sample - c->prev_sample;
148

    
149
    if (delta < 0) {
150
        sign = 1;
151
        delta = -delta;
152
    }
153

    
154
    step_index = c->step_index;
155

    
156
    /* nibble = 4 * delta / step_table[step_index]; */
157
    nibble = (delta << 2) / step_table[step_index];
158

    
159
    if (nibble > 7)
160
        nibble = 7;
161

    
162
    step_index += index_table[nibble];
163
    if (step_index < 0)
164
        step_index = 0;
165
    if (step_index > 88)
166
        step_index = 88;
167

    
168
    /* what the decoder will find */
169
    predicted_delta = ((step_table[step_index] * nibble) / 4) + (step_table[step_index] / 8);
170

    
171
    if (sign)
172
        c->prev_sample -= predicted_delta;
173
    else
174
        c->prev_sample += predicted_delta;
175

    
176
    CLAMP_TO_SHORT(c->prev_sample);
177

    
178

    
179
    nibble += sign << 3; /* sign * 8 */   
180

    
181
    /* save back */
182
    c->step_index = step_index;
183

    
184
    return nibble;
185
}
186

    
187
static int adpcm_encode_frame(AVCodecContext *avctx,
188
                            unsigned char *frame, int buf_size, void *data)
189
{
190
    int n;
191
    short *samples;
192
    unsigned char *dst;
193
    ADPCMContext *c = avctx->priv_data;
194

    
195
    dst = frame;
196
    samples = (short *)data;
197
/*    n = (BLKSIZE - 4 * avctx->channels) / (2 * 8 * avctx->channels); */
198

    
199
    switch(avctx->codec->id) {
200
    case CODEC_ID_ADPCM_IMA_QT: /* XXX: can't test until we get .mov writer */
201
        break;
202
    case CODEC_ID_ADPCM_IMA_WAV:
203
        n = avctx->frame_size / 8;
204
            c->status[0].prev_sample = (signed short)samples[0]; /* XXX */
205
/*            c->status[0].step_index = 0; *//* XXX: not sure how to init the state machine */
206
            *dst++ = (c->status[0].prev_sample) & 0xFF; /* little endian */
207
            *dst++ = (c->status[0].prev_sample >> 8) & 0xFF;
208
            *dst++ = (unsigned char)c->status[0].step_index;
209
            *dst++ = 0; /* unknown */
210
            samples++;
211
            if (avctx->channels == 2) {
212
                c->status[1].prev_sample = (signed short)samples[0];
213
/*                c->status[1].step_index = 0; */
214
                *dst++ = (c->status[1].prev_sample) & 0xFF;
215
                *dst++ = (c->status[1].prev_sample >> 8) & 0xFF;
216
                *dst++ = (unsigned char)c->status[1].step_index;
217
                *dst++ = 0;
218
                samples++;
219
            }
220
        
221
            /* stereo: 4 bytes (8 samples) for left, 4 bytes for right, 4 bytes left, ... */
222
            for (; n>0; n--) {
223
                *dst = adpcm_ima_compress_sample(&c->status[0], samples[0]) & 0x0F;
224
                *dst |= (adpcm_ima_compress_sample(&c->status[0], samples[avctx->channels]) << 4) & 0xF0;
225
                dst++;
226
                *dst = adpcm_ima_compress_sample(&c->status[0], samples[avctx->channels * 2]) & 0x0F;
227
                *dst |= (adpcm_ima_compress_sample(&c->status[0], samples[avctx->channels * 3]) << 4) & 0xF0;
228
                dst++;
229
                *dst = adpcm_ima_compress_sample(&c->status[0], samples[avctx->channels * 4]) & 0x0F;
230
                *dst |= (adpcm_ima_compress_sample(&c->status[0], samples[avctx->channels * 5]) << 4) & 0xF0;
231
                dst++;
232
                *dst = adpcm_ima_compress_sample(&c->status[0], samples[avctx->channels * 6]) & 0x0F;
233
                *dst |= (adpcm_ima_compress_sample(&c->status[0], samples[avctx->channels * 7]) << 4) & 0xF0;
234
                dst++;
235
                /* right channel */
236
                if (avctx->channels == 2) {
237
                    *dst = adpcm_ima_compress_sample(&c->status[1], samples[1]);
238
                    *dst |= adpcm_ima_compress_sample(&c->status[1], samples[3]) << 4;
239
                    dst++;
240
                    *dst = adpcm_ima_compress_sample(&c->status[1], samples[5]);
241
                    *dst |= adpcm_ima_compress_sample(&c->status[1], samples[7]) << 4;
242
                    dst++;
243
                    *dst = adpcm_ima_compress_sample(&c->status[1], samples[9]);
244
                    *dst |= adpcm_ima_compress_sample(&c->status[1], samples[11]) << 4;
245
                    dst++;
246
                    *dst = adpcm_ima_compress_sample(&c->status[1], samples[13]);
247
                    *dst |= adpcm_ima_compress_sample(&c->status[1], samples[15]) << 4;
248
                    dst++;
249
                }
250
                samples += 8 * avctx->channels;
251
            }
252
        break;
253
    default:
254
        return -1;
255
    }
256
    avctx->key_frame = 1;
257
    return dst - frame;
258
}
259

    
260
static int adpcm_decode_init(AVCodecContext * avctx)
261
{
262
    ADPCMContext *c = avctx->priv_data;
263

    
264
    c->channel = 0;
265
    c->status[0].predictor = c->status[1].predictor = 0;
266
    c->status[0].step_index = c->status[1].step_index = 0;
267
    c->status[0].step = c->status[1].step = 0;
268

    
269
    switch(avctx->codec->id) {
270
    default:
271
        break;
272
    }
273
    return 0;
274
}
275

    
276
static inline short adpcm_ima_expand_nibble(ADPCMChannelStatus *c, char nibble)
277
{
278
    int step_index;
279
    int predictor;
280
    int sign, delta, diff, step;
281

    
282
    predictor = c->predictor;
283
    step_index = c->step_index + index_table[(unsigned)nibble];
284
    if (step_index < 0) step_index = 0;
285
    if (step_index > 88) step_index = 88;
286

    
287
    step = c->step;
288

    
289
/*
290
    diff = ((signed)((nibble & 0x08)?(nibble | 0xF0):(nibble)) + 0.5) * step / 4;
291
    predictor += diff;
292
*/
293
    sign = nibble & 8;
294
    delta = nibble & 7;
295
    diff = step >> 3;
296
    if (delta & 4) diff += step;
297
    if (delta & 2) diff += step >> 1;
298
    if (delta & 1) diff += step >> 2;
299
    if (sign) predictor -= diff;
300
    else predictor += diff;
301

    
302
    CLAMP_TO_SHORT(predictor);
303
    c->predictor = predictor;
304
    c->step_index = step_index;
305
    c->step = step_table[step_index];
306
    
307
    return (short)predictor;
308
}
309

    
310
static inline short adpcm_ms_expand_nibble(ADPCMChannelStatus *c, char nibble)
311
{
312
    int predictor;
313

    
314
    predictor = (((c->sample1) * (c->coeff1)) + ((c->sample2) * (c->coeff2))) / 256;
315
    predictor += (signed)((nibble & 0x08)?(nibble - 0x10):(nibble)) * c->idelta;
316
    CLAMP_TO_SHORT(predictor);
317

    
318
    c->sample2 = c->sample1;
319
    c->sample1 = predictor;
320
    c->idelta = (AdaptationTable[(int)nibble] * c->idelta) / 256;
321
    if (c->idelta < 16) c->idelta = 16;
322

    
323
    return (short)predictor;
324
}
325

    
326
static int adpcm_decode_frame(AVCodecContext *avctx,
327
                            void *data, int *data_size,
328
                            UINT8 *buf, int buf_size)
329
{
330
    ADPCMContext *c = avctx->priv_data;
331
    ADPCMChannelStatus *cs;
332
    int n, m, channel;
333
    int block_predictor[2];
334
    short *samples;
335
    UINT8 *src;
336
    int st; /* stereo */
337

    
338
    samples = data;
339
    src = buf;
340

    
341
    st = avctx->channels == 2;
342

    
343
    switch(avctx->codec->id) {
344
    case CODEC_ID_ADPCM_IMA_QT:
345
        n = (buf_size - 2);/* >> 2*avctx->channels;*/
346
        channel = c->channel;
347
        cs = &(c->status[channel]);
348
        /* (pppppp) (piiiiiii) */
349

    
350
        /* Bits 15-7 are the _top_ 9 bits of the 16-bit initial predictor value */
351
        cs->predictor = (*src++) << 8;
352
        cs->predictor |= (*src & 0x80);
353
        cs->predictor &= 0xFF80;
354

    
355
        /* sign extension */
356
        if(cs->predictor & 0x8000)
357
            cs->predictor -= 0x10000;
358

    
359
        CLAMP_TO_SHORT(cs->predictor);
360

    
361
        cs->step_index = (*src++) & 0x7F;
362

    
363
        if (cs->step_index > 88) fprintf(stderr, "ERROR: step_index = %i\n", cs->step_index);
364
        if (cs->step_index > 88) cs->step_index = 88;
365

    
366
        cs->step = step_table[cs->step_index];
367

    
368
        if (st && channel)
369
            samples++;
370

    
371
        *samples++ = cs->predictor;
372
        samples += st;
373

    
374
        for(m=32; n>0 && m>0; n--, m--) { /* in QuickTime, IMA is encoded by chuncks of 34 bytes (=64 samples) */
375
            *samples = adpcm_ima_expand_nibble(cs, src[0] & 0x0F);
376
            samples += avctx->channels;
377
            *samples = adpcm_ima_expand_nibble(cs, (src[0] >> 4) & 0x0F);
378
            samples += avctx->channels;
379
            src ++;
380
        }
381

    
382
        if(st) { /* handle stereo interlacing */
383
            c->channel = (channel + 1) % 2; /* we get one packet for left, then one for right data */
384
            if(channel == 0) { /* wait for the other packet before outputing anything */
385
                *data_size = 0;
386
                return src - buf;
387
            }
388
        }
389
        break;
390
    case CODEC_ID_ADPCM_IMA_WAV:
391
        if (buf_size > BLKSIZE) {
392
            if (avctx->block_align != 0)
393
                buf_size = avctx->block_align;
394
            else
395
                buf_size = BLKSIZE;
396
        }
397
        n = buf_size - 4 * avctx->channels;
398
        cs = &(c->status[0]);
399
        cs->predictor = (*src++) & 0x0FF;
400
        cs->predictor |= ((*src++) << 8) & 0x0FF00;
401
        if(cs->predictor & 0x8000)
402
            cs->predictor -= 0x10000;
403
        CLAMP_TO_SHORT(cs->predictor);
404

    
405
        *samples++ = cs->predictor;
406

    
407
        cs->step_index = *src++;
408
        if (cs->step_index < 0) cs->step_index = 0;
409
        if (cs->step_index > 88) cs->step_index = 88;
410
        if (*src++) fprintf(stderr, "unused byte should be null !!\n"); /* unused */
411

    
412
        if (st) {
413
            cs = &(c->status[1]);
414
            cs->predictor = (*src++) & 0x0FF;
415
            cs->predictor |= ((*src++) << 8) & 0x0FF00;
416
            if(cs->predictor & 0x8000)
417
                cs->predictor -= 0x10000;
418
            CLAMP_TO_SHORT(cs->predictor);
419

    
420
            *samples++ = cs->predictor;
421

    
422
            cs->step_index = *src++;
423
            if (cs->step_index < 0) cs->step_index = 0;
424
            if (cs->step_index > 88) cs->step_index = 88;
425
            src++; /* unused */
426
        }
427
        cs = &(c->status[0]);
428

    
429

    
430
        for(m=3; n>0; n--, m--) {
431
            *samples++ = adpcm_ima_expand_nibble(&c->status[0], src[0] & 0x0F);
432
            if (st)
433
                *samples++ = adpcm_ima_expand_nibble(&c->status[1], src[4] & 0x0F);
434
            *samples++ = adpcm_ima_expand_nibble(&c->status[0], (src[0] >> 4) & 0x0F);
435
            if (st)
436
                *samples++ = adpcm_ima_expand_nibble(&c->status[1], (src[4] >> 4) & 0x0F);
437
            src ++;
438
            if (st && !m) {
439
                m=3;
440
                src+=4;
441
            }
442
        }
443
        break;
444
    case CODEC_ID_ADPCM_MS:
445

    
446
        if (buf_size > BLKSIZE) {
447
            if (avctx->block_align != 0)
448
                buf_size = avctx->block_align;
449
            else
450
                buf_size = BLKSIZE;
451
        }
452
        n = buf_size - 7 * avctx->channels;
453
        if (n < 0)
454
            return -1;
455
        block_predictor[0] = (*src++); /* should be bound */
456
        block_predictor[0] = (block_predictor[0] < 0)?(0):((block_predictor[0] > 7)?(7):(block_predictor[0]));
457
        block_predictor[1] = 0;
458
        if (st)
459
            block_predictor[1] = (*src++);
460
        block_predictor[1] = (block_predictor[1] < 0)?(0):((block_predictor[1] > 7)?(7):(block_predictor[1]));
461
        c->status[0].idelta = ((*src & 0xFF) | ((src[1] << 8) & 0xFF00));
462
        if (c->status[0].idelta & 0x08000)
463
            c->status[0].idelta -= 0x10000;
464
        src+=2;
465
        if (st)
466
            c->status[1].idelta = ((*src & 0xFF) | ((src[1] << 8) & 0xFF00));
467
        if (st && c->status[1].idelta & 0x08000)
468
            c->status[1].idelta |= 0xFFFF0000;
469
        if (st)
470
            src+=2;
471
        c->status[0].coeff1 = AdaptCoeff1[block_predictor[0]];
472
        c->status[0].coeff2 = AdaptCoeff2[block_predictor[0]];
473
        c->status[1].coeff1 = AdaptCoeff1[block_predictor[1]];
474
        c->status[1].coeff2 = AdaptCoeff2[block_predictor[1]];
475
        
476
        c->status[0].sample1 = ((*src & 0xFF) | ((src[1] << 8) & 0xFF00));
477
        src+=2;
478
        if (st) c->status[1].sample1 = ((*src & 0xFF) | ((src[1] << 8) & 0xFF00));
479
        if (st) src+=2;
480
        c->status[0].sample2 = ((*src & 0xFF) | ((src[1] << 8) & 0xFF00));
481
        src+=2;
482
        if (st) c->status[1].sample2 = ((*src & 0xFF) | ((src[1] << 8) & 0xFF00));
483
        if (st) src+=2;
484

    
485
        *samples++ = c->status[0].sample1;
486
        if (st) *samples++ = c->status[1].sample1;
487
        *samples++ = c->status[0].sample2;
488
        if (st) *samples++ = c->status[1].sample2;
489
        for(;n>0;n--) {
490
            *samples++ = adpcm_ms_expand_nibble(&c->status[0], (src[0] >> 4) & 0x0F);
491
            *samples++ = adpcm_ms_expand_nibble(&c->status[st], src[0] & 0x0F);
492
            src ++;
493
        }
494
        break;
495
    default:
496
        *data_size = 0;
497
        return -1;
498
    }
499
    *data_size = (UINT8 *)samples - (UINT8 *)data;
500
    return src - buf;
501
}
502

    
503
#define ADPCM_CODEC(id, name)                   \
504
AVCodec name ## _encoder = {                    \
505
    #name,                                      \
506
    CODEC_TYPE_AUDIO,                           \
507
    id,                                         \
508
    sizeof(ADPCMContext),                       \
509
    adpcm_encode_init,                          \
510
    adpcm_encode_frame,                         \
511
    adpcm_encode_close,                         \
512
    NULL,                                       \
513
};                                              \
514
AVCodec name ## _decoder = {                    \
515
    #name,                                      \
516
    CODEC_TYPE_AUDIO,                           \
517
    id,                                         \
518
    sizeof(ADPCMContext),                       \
519
    adpcm_decode_init,                          \
520
    NULL,                                       \
521
    NULL,                                       \
522
    adpcm_decode_frame,                         \
523
};
524

    
525
ADPCM_CODEC(CODEC_ID_ADPCM_IMA_QT, adpcm_ima_qt);
526
ADPCM_CODEC(CODEC_ID_ADPCM_IMA_WAV, adpcm_ima_wav);
527
ADPCM_CODEC(CODEC_ID_ADPCM_MS, adpcm_ms);
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529
#undef ADPCM_CODEC
530