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1
/*
2
 * ADPCM codecs
3
 * Copyright (c) 2001-2003 The ffmpeg Project
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
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 * 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
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 */
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#include "avcodec.h"
20

    
21
/**
22
 * @file adpcm.c
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 * ADPCM codecs.
24
 * First version by Francois Revol (revol@free.fr)
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 * Fringe ADPCM codecs (e.g., DK3, DK4, Westwood)
26
 *   by Mike Melanson (melanson@pcisys.net)
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 * CD-ROM XA ADPCM codec by BERO
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 *
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 * Features and limitations:
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 *
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 * Reference documents:
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 * http://www.pcisys.net/~melanson/codecs/simpleaudio.html
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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
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 *
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 * CD-ROM XA:
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 * http://ku-www.ss.titech.ac.jp/~yatsushi/xaadpcm.html
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 * vagpack & depack http://homepages.compuserve.de/bITmASTER32/psx-index.html
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 * readstr http://www.geocities.co.jp/Playtown/2004/
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 */
44

    
45
#define BLKSIZE 1024
46

    
47
#define CLAMP_TO_SHORT(value) \
48
if (value > 32767) \
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    value = 32767; \
50
else if (value < -32768) \
51
    value = -32768; \
52

    
53
/* step_table[] and index_table[] are from the ADPCM reference source */
54
/* This is the index table: */
55
static const int index_table[16] = {
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    -1, -1, -1, -1, 2, 4, 6, 8,
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    -1, -1, -1, -1, 2, 4, 6, 8,
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};
59

    
60
/** 
61
 * This is the step table. Note that many programs use slight deviations from
62
 * this table, but such deviations are negligible:
63
 */
64
static const int step_table[89] = {
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    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
74
};
75

    
76
/* These are for MS-ADPCM */
77
/* AdaptationTable[], AdaptCoeff1[], and AdaptCoeff2[] are from libsndfile */
78
static const 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
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};
82

    
83
static const int AdaptCoeff1[] = {
84
        256, 512, 0, 192, 240, 460, 392
85
};
86

    
87
static const int AdaptCoeff2[] = {
88
        0, -256, 0, 64, 0, -208, -232
89
};
90

    
91
/* These are for CD-ROM XA ADPCM */
92
static const int xa_adpcm_table[5][2] = {
93
   {   0,   0 },
94
   {  60,   0 },
95
   { 115, -52 },
96
   {  98, -55 },
97
   { 122, -60 }
98
};
99

    
100
/* end of tables */
101

    
102
typedef struct ADPCMChannelStatus {
103
    int predictor;
104
    short int step_index;
105
    int step;
106
    /* for encoding */
107
    int prev_sample;
108

    
109
    /* MS version */
110
    short sample1;
111
    short sample2;
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    int coeff1;
113
    int coeff2;
114
    int idelta;
115
} ADPCMChannelStatus;
116

    
117
typedef struct ADPCMContext {
118
    int channel; /* for stereo MOVs, decode left, then decode right, then tell it's decoded */
119
    ADPCMChannelStatus status[2];
120
    short sample_buffer[32]; /* hold left samples while waiting for right samples */
121
} ADPCMContext;
122

    
123
/* XXX: implement encoding */
124

    
125
#ifdef CONFIG_ENCODERS
126
static int adpcm_encode_init(AVCodecContext *avctx)
127
{
128
    if (avctx->channels > 2)
129
        return -1; /* only stereo or mono =) */
130
    switch(avctx->codec->id) {
131
    case CODEC_ID_ADPCM_IMA_QT:
132
        av_log(avctx, AV_LOG_ERROR, "ADPCM: codec adpcm_ima_qt unsupported for encoding !\n");
133
        avctx->frame_size = 64; /* XXX: can multiple of avctx->channels * 64 (left and right blocks are interleaved) */
134
        return -1;
135
        break;
136
    case CODEC_ID_ADPCM_IMA_WAV:
137
        avctx->frame_size = (BLKSIZE - 4 * avctx->channels) * 8 / (4 * avctx->channels) + 1; /* each 16 bits sample gives one nibble */
138
                                                             /* and we have 4 bytes per channel overhead */
139
        avctx->block_align = BLKSIZE;
140
        /* seems frame_size isn't taken into account... have to buffer the samples :-( */
141
        break;
142
    case CODEC_ID_ADPCM_MS:
143
        av_log(avctx, AV_LOG_ERROR, "ADPCM: codec adpcm_ms unsupported for encoding !\n");
144
        return -1;
145
        break;
146
    default:
147
        return -1;
148
        break;
149
    }
150

    
151
    avctx->coded_frame= avcodec_alloc_frame();
152
    avctx->coded_frame->key_frame= 1;
153

    
154
    return 0;
155
}
156

    
157
static int adpcm_encode_close(AVCodecContext *avctx)
158
{
159
    av_freep(&avctx->coded_frame);
160

    
161
    return 0;
162
}
163

    
164

    
165
static inline unsigned char adpcm_ima_compress_sample(ADPCMChannelStatus *c, short sample)
166
{
167
    int step_index;
168
    unsigned char nibble;
169
    
170
    int sign = 0; /* sign bit of the nibble (MSB) */
171
    int delta, predicted_delta;
172

    
173
    delta = sample - c->prev_sample;
174

    
175
    if (delta < 0) {
176
        sign = 1;
177
        delta = -delta;
178
    }
179

    
180
    step_index = c->step_index;
181

    
182
    /* nibble = 4 * delta / step_table[step_index]; */
183
    nibble = (delta << 2) / step_table[step_index];
184

    
185
    if (nibble > 7)
186
        nibble = 7;
187

    
188
    step_index += index_table[nibble];
189
    if (step_index < 0)
190
        step_index = 0;
191
    if (step_index > 88)
192
        step_index = 88;
193

    
194
    /* what the decoder will find */
195
    predicted_delta = ((step_table[step_index] * nibble) / 4) + (step_table[step_index] / 8);
196

    
197
    if (sign)
198
        c->prev_sample -= predicted_delta;
199
    else
200
        c->prev_sample += predicted_delta;
201

    
202
    CLAMP_TO_SHORT(c->prev_sample);
203

    
204

    
205
    nibble += sign << 3; /* sign * 8 */   
206

    
207
    /* save back */
208
    c->step_index = step_index;
209

    
210
    return nibble;
211
}
212

    
213
static int adpcm_encode_frame(AVCodecContext *avctx,
214
                            unsigned char *frame, int buf_size, void *data)
215
{
216
    int n;
217
    short *samples;
218
    unsigned char *dst;
219
    ADPCMContext *c = avctx->priv_data;
220

    
221
    dst = frame;
222
    samples = (short *)data;
223
/*    n = (BLKSIZE - 4 * avctx->channels) / (2 * 8 * avctx->channels); */
224

    
225
    switch(avctx->codec->id) {
226
    case CODEC_ID_ADPCM_IMA_QT: /* XXX: can't test until we get .mov writer */
227
        break;
228
    case CODEC_ID_ADPCM_IMA_WAV:
229
        n = avctx->frame_size / 8;
230
            c->status[0].prev_sample = (signed short)samples[0]; /* XXX */
231
/*            c->status[0].step_index = 0; *//* XXX: not sure how to init the state machine */
232
            *dst++ = (c->status[0].prev_sample) & 0xFF; /* little endian */
233
            *dst++ = (c->status[0].prev_sample >> 8) & 0xFF;
234
            *dst++ = (unsigned char)c->status[0].step_index;
235
            *dst++ = 0; /* unknown */
236
            samples++;
237
            if (avctx->channels == 2) {
238
                c->status[1].prev_sample = (signed short)samples[1];
239
/*                c->status[1].step_index = 0; */
240
                *dst++ = (c->status[1].prev_sample) & 0xFF;
241
                *dst++ = (c->status[1].prev_sample >> 8) & 0xFF;
242
                *dst++ = (unsigned char)c->status[1].step_index;
243
                *dst++ = 0;
244
                samples++;
245
            }
246
        
247
            /* stereo: 4 bytes (8 samples) for left, 4 bytes for right, 4 bytes left, ... */
248
            for (; n>0; n--) {
249
                *dst = adpcm_ima_compress_sample(&c->status[0], samples[0]) & 0x0F;
250
                *dst |= (adpcm_ima_compress_sample(&c->status[0], samples[avctx->channels]) << 4) & 0xF0;
251
                dst++;
252
                *dst = adpcm_ima_compress_sample(&c->status[0], samples[avctx->channels * 2]) & 0x0F;
253
                *dst |= (adpcm_ima_compress_sample(&c->status[0], samples[avctx->channels * 3]) << 4) & 0xF0;
254
                dst++;
255
                *dst = adpcm_ima_compress_sample(&c->status[0], samples[avctx->channels * 4]) & 0x0F;
256
                *dst |= (adpcm_ima_compress_sample(&c->status[0], samples[avctx->channels * 5]) << 4) & 0xF0;
257
                dst++;
258
                *dst = adpcm_ima_compress_sample(&c->status[0], samples[avctx->channels * 6]) & 0x0F;
259
                *dst |= (adpcm_ima_compress_sample(&c->status[0], samples[avctx->channels * 7]) << 4) & 0xF0;
260
                dst++;
261
                /* right channel */
262
                if (avctx->channels == 2) {
263
                    *dst = adpcm_ima_compress_sample(&c->status[1], samples[1]);
264
                    *dst |= adpcm_ima_compress_sample(&c->status[1], samples[3]) << 4;
265
                    dst++;
266
                    *dst = adpcm_ima_compress_sample(&c->status[1], samples[5]);
267
                    *dst |= adpcm_ima_compress_sample(&c->status[1], samples[7]) << 4;
268
                    dst++;
269
                    *dst = adpcm_ima_compress_sample(&c->status[1], samples[9]);
270
                    *dst |= adpcm_ima_compress_sample(&c->status[1], samples[11]) << 4;
271
                    dst++;
272
                    *dst = adpcm_ima_compress_sample(&c->status[1], samples[13]);
273
                    *dst |= adpcm_ima_compress_sample(&c->status[1], samples[15]) << 4;
274
                    dst++;
275
                }
276
                samples += 8 * avctx->channels;
277
            }
278
        break;
279
    default:
280
        return -1;
281
    }
282
    return dst - frame;
283
}
284
#endif //CONFIG_ENCODERS
285

    
286
static int adpcm_decode_init(AVCodecContext * avctx)
287
{
288
    ADPCMContext *c = avctx->priv_data;
289

    
290
    c->channel = 0;
291
    c->status[0].predictor = c->status[1].predictor = 0;
292
    c->status[0].step_index = c->status[1].step_index = 0;
293
    c->status[0].step = c->status[1].step = 0;
294

    
295
    switch(avctx->codec->id) {
296
    default:
297
        break;
298
    }
299
    return 0;
300
}
301

    
302
static inline short adpcm_ima_expand_nibble(ADPCMChannelStatus *c, char nibble, int shift)
303
{
304
    int step_index;
305
    int predictor;
306
    int sign, delta, diff, step;
307

    
308
    step = step_table[c->step_index];
309
    step_index = c->step_index + index_table[(unsigned)nibble];
310
    if (step_index < 0) step_index = 0;
311
    else if (step_index > 88) step_index = 88;
312

    
313
    sign = nibble & 8;
314
    delta = nibble & 7;
315
    /* perform direct multiplication instead of series of jumps proposed by
316
     * the reference ADPCM implementation since modern CPUs can do the mults
317
     * quickly enough */
318
    diff = ((2 * delta + 1) * step) >> shift;
319
    predictor = c->predictor;
320
    if (sign) predictor -= diff;
321
    else predictor += diff;
322

    
323
    CLAMP_TO_SHORT(predictor);
324
    c->predictor = predictor;
325
    c->step_index = step_index;
326

    
327
    return (short)predictor;
328
}
329

    
330
static inline short adpcm_ms_expand_nibble(ADPCMChannelStatus *c, char nibble)
331
{
332
    int predictor;
333

    
334
    predictor = (((c->sample1) * (c->coeff1)) + ((c->sample2) * (c->coeff2))) / 256;
335
    predictor += (signed)((nibble & 0x08)?(nibble - 0x10):(nibble)) * c->idelta;
336
    CLAMP_TO_SHORT(predictor);
337

    
338
    c->sample2 = c->sample1;
339
    c->sample1 = predictor;
340
    c->idelta = (AdaptationTable[(int)nibble] * c->idelta) / 256;
341
    if (c->idelta < 16) c->idelta = 16;
342

    
343
    return (short)predictor;
344
}
345

    
346
static void xa_decode(short *out, const unsigned char *in, 
347
    ADPCMChannelStatus *left, ADPCMChannelStatus *right, int inc)
348
{
349
    int i, j;
350
    int shift,filter,f0,f1;
351
    int s_1,s_2;
352
    int d,s,t;
353

    
354
    for(i=0;i<4;i++) {
355

    
356
        shift  = 12 - (in[4+i*2] & 15);
357
        filter = in[4+i*2] >> 4;
358
        f0 = xa_adpcm_table[filter][0];
359
        f1 = xa_adpcm_table[filter][1];
360

    
361
        s_1 = left->sample1;
362
        s_2 = left->sample2;
363

    
364
        for(j=0;j<28;j++) {
365
            d = in[16+i+j*4];
366

    
367
            t = (signed char)(d<<4)>>4;
368
            s = ( t<<shift ) + ((s_1*f0 + s_2*f1+32)>>6);
369
            CLAMP_TO_SHORT(s);
370
            *out = s;
371
            out += inc;
372
            s_2 = s_1;
373
            s_1 = s;
374
        }
375

    
376
        if (inc==2) { /* stereo */
377
            left->sample1 = s_1;
378
            left->sample2 = s_2;
379
            s_1 = right->sample1;
380
            s_2 = right->sample2;
381
            out = out + 1 - 28*2;
382
        }
383

    
384
        shift  = 12 - (in[5+i*2] & 15);
385
        filter = in[5+i*2] >> 4;
386

    
387
        f0 = xa_adpcm_table[filter][0];
388
        f1 = xa_adpcm_table[filter][1];
389

    
390
        for(j=0;j<28;j++) {
391
            d = in[16+i+j*4];
392

    
393
            t = (signed char)d >> 4;
394
            s = ( t<<shift ) + ((s_1*f0 + s_2*f1+32)>>6);
395
            CLAMP_TO_SHORT(s);
396
            *out = s;
397
            out += inc;
398
            s_2 = s_1;
399
            s_1 = s;
400
        }
401

    
402
        if (inc==2) { /* stereo */
403
            right->sample1 = s_1;
404
            right->sample2 = s_2;
405
            out -= 1;
406
        } else {
407
            left->sample1 = s_1;
408
            left->sample2 = s_2;
409
        }
410
    }
411
}
412

    
413

    
414
/* DK3 ADPCM support macro */
415
#define DK3_GET_NEXT_NIBBLE() \
416
    if (decode_top_nibble_next) \
417
    { \
418
        nibble = (last_byte >> 4) & 0x0F; \
419
        decode_top_nibble_next = 0; \
420
    } \
421
    else \
422
    { \
423
        last_byte = *src++; \
424
        if (src >= buf + buf_size) break; \
425
        nibble = last_byte & 0x0F; \
426
        decode_top_nibble_next = 1; \
427
    }
428

    
429
static int adpcm_decode_frame(AVCodecContext *avctx,
430
                            void *data, int *data_size,
431
                            uint8_t *buf, int buf_size)
432
{
433
    ADPCMContext *c = avctx->priv_data;
434
    ADPCMChannelStatus *cs;
435
    int n, m, channel, i;
436
    int block_predictor[2];
437
    short *samples;
438
    uint8_t *src;
439
    int st; /* stereo */
440

    
441
    /* DK3 ADPCM accounting variables */
442
    unsigned char last_byte = 0;
443
    unsigned char nibble;
444
    int decode_top_nibble_next = 0;
445
    int diff_channel;
446

    
447
    if (!buf_size)
448
        return 0;
449

    
450
    samples = data;
451
    src = buf;
452

    
453
    st = avctx->channels == 2;
454

    
455
    switch(avctx->codec->id) {
456
    case CODEC_ID_ADPCM_IMA_QT:
457
        n = (buf_size - 2);/* >> 2*avctx->channels;*/
458
        channel = c->channel;
459
        cs = &(c->status[channel]);
460
        /* (pppppp) (piiiiiii) */
461

    
462
        /* Bits 15-7 are the _top_ 9 bits of the 16-bit initial predictor value */
463
        cs->predictor = (*src++) << 8;
464
        cs->predictor |= (*src & 0x80);
465
        cs->predictor &= 0xFF80;
466

    
467
        /* sign extension */
468
        if(cs->predictor & 0x8000)
469
            cs->predictor -= 0x10000;
470

    
471
        CLAMP_TO_SHORT(cs->predictor);
472

    
473
        cs->step_index = (*src++) & 0x7F;
474

    
475
        if (cs->step_index > 88) av_log(avctx, AV_LOG_ERROR, "ERROR: step_index = %i\n", cs->step_index);
476
        if (cs->step_index > 88) cs->step_index = 88;
477

    
478
        cs->step = step_table[cs->step_index];
479

    
480
        if (st && channel)
481
            samples++;
482

    
483
        for(m=32; n>0 && m>0; n--, m--) { /* in QuickTime, IMA is encoded by chuncks of 34 bytes (=64 samples) */
484
            *samples = adpcm_ima_expand_nibble(cs, src[0] & 0x0F, 3);
485
            samples += avctx->channels;
486
            *samples = adpcm_ima_expand_nibble(cs, (src[0] >> 4) & 0x0F, 3);
487
            samples += avctx->channels;
488
            src ++;
489
        }
490

    
491
        if(st) { /* handle stereo interlacing */
492
            c->channel = (channel + 1) % 2; /* we get one packet for left, then one for right data */
493
            if(channel == 1) { /* wait for the other packet before outputing anything */
494
                *data_size = 0;
495
                return src - buf;
496
            }
497
        }
498
        break;
499
    case CODEC_ID_ADPCM_IMA_WAV:
500
        if (avctx->block_align != 0 && buf_size > avctx->block_align)
501
            buf_size = avctx->block_align;
502

    
503
        for(i=0; i<avctx->channels; i++){
504
            cs = &(c->status[i]);
505
            cs->predictor = *src++;
506
            cs->predictor |= (*src++) << 8;
507
            if(cs->predictor & 0x8000)
508
                cs->predictor -= 0x10000;
509
            CLAMP_TO_SHORT(cs->predictor);
510

    
511
        // XXX: is this correct ??: *samples++ = cs->predictor;
512

    
513
            cs->step_index = *src++;
514
            if (cs->step_index < 0) cs->step_index = 0;
515
            if (cs->step_index > 88) cs->step_index = 88;
516
            if (*src++) av_log(avctx, AV_LOG_ERROR, "unused byte should be null !!\n"); /* unused */
517
        }
518

    
519
        for(m=4; src < (buf + buf_size);) {
520
            *samples++ = adpcm_ima_expand_nibble(&c->status[0], src[0] & 0x0F, 3);
521
            if (st)
522
                *samples++ = adpcm_ima_expand_nibble(&c->status[1], src[4] & 0x0F, 3);
523
            *samples++ = adpcm_ima_expand_nibble(&c->status[0], (src[0] >> 4) & 0x0F, 3);
524
            if (st) {
525
                *samples++ = adpcm_ima_expand_nibble(&c->status[1], (src[4] >> 4) & 0x0F, 3);
526
                if (!--m) {
527
                    m=4;
528
                    src+=4;
529
                }
530
            }
531
            src++;
532
        }
533
        break;
534
    case CODEC_ID_ADPCM_4XM:
535
        cs = &(c->status[0]);
536
        c->status[0].predictor= (int16_t)(src[0] + (src[1]<<8)); src+=2;
537
        if(st){
538
            c->status[1].predictor= (int16_t)(src[0] + (src[1]<<8)); src+=2;
539
        }
540
        c->status[0].step_index= (int16_t)(src[0] + (src[1]<<8)); src+=2;
541
        if(st){
542
            c->status[1].step_index= (int16_t)(src[0] + (src[1]<<8)); src+=2;
543
        }
544
        if (cs->step_index < 0) cs->step_index = 0;
545
        if (cs->step_index > 88) cs->step_index = 88;
546

    
547
        m= (buf_size - (src - buf))>>st;
548
        for(i=0; i<m; i++) {
549
            *samples++ = adpcm_ima_expand_nibble(&c->status[0], src[i] & 0x0F, 4);
550
            if (st)
551
                *samples++ = adpcm_ima_expand_nibble(&c->status[1], src[i+m] & 0x0F, 4);
552
            *samples++ = adpcm_ima_expand_nibble(&c->status[0], src[i] >> 4, 4);
553
            if (st)
554
                *samples++ = adpcm_ima_expand_nibble(&c->status[1], src[i+m] >> 4, 4);
555
        }
556

    
557
        src += m<<st;
558

    
559
        break;
560
    case CODEC_ID_ADPCM_MS:
561
        if (avctx->block_align != 0 && buf_size > avctx->block_align)
562
            buf_size = avctx->block_align;
563
        n = buf_size - 7 * avctx->channels;
564
        if (n < 0)
565
            return -1;
566
        block_predictor[0] = (*src++); /* should be bound */
567
        block_predictor[0] = (block_predictor[0] < 0)?(0):((block_predictor[0] > 7)?(7):(block_predictor[0]));
568
        block_predictor[1] = 0;
569
        if (st)
570
            block_predictor[1] = (*src++);
571
        block_predictor[1] = (block_predictor[1] < 0)?(0):((block_predictor[1] > 7)?(7):(block_predictor[1]));
572
        c->status[0].idelta = ((*src & 0xFF) | ((src[1] << 8) & 0xFF00));
573
        if (c->status[0].idelta & 0x08000)
574
            c->status[0].idelta -= 0x10000;
575
        src+=2;
576
        if (st)
577
            c->status[1].idelta = ((*src & 0xFF) | ((src[1] << 8) & 0xFF00));
578
        if (st && c->status[1].idelta & 0x08000)
579
            c->status[1].idelta |= 0xFFFF0000;
580
        if (st)
581
            src+=2;
582
        c->status[0].coeff1 = AdaptCoeff1[block_predictor[0]];
583
        c->status[0].coeff2 = AdaptCoeff2[block_predictor[0]];
584
        c->status[1].coeff1 = AdaptCoeff1[block_predictor[1]];
585
        c->status[1].coeff2 = AdaptCoeff2[block_predictor[1]];
586
        
587
        c->status[0].sample1 = ((*src & 0xFF) | ((src[1] << 8) & 0xFF00));
588
        src+=2;
589
        if (st) c->status[1].sample1 = ((*src & 0xFF) | ((src[1] << 8) & 0xFF00));
590
        if (st) src+=2;
591
        c->status[0].sample2 = ((*src & 0xFF) | ((src[1] << 8) & 0xFF00));
592
        src+=2;
593
        if (st) c->status[1].sample2 = ((*src & 0xFF) | ((src[1] << 8) & 0xFF00));
594
        if (st) src+=2;
595

    
596
        *samples++ = c->status[0].sample1;
597
        if (st) *samples++ = c->status[1].sample1;
598
        *samples++ = c->status[0].sample2;
599
        if (st) *samples++ = c->status[1].sample2;
600
        for(;n>0;n--) {
601
            *samples++ = adpcm_ms_expand_nibble(&c->status[0], (src[0] >> 4) & 0x0F);
602
            *samples++ = adpcm_ms_expand_nibble(&c->status[st], src[0] & 0x0F);
603
            src ++;
604
        }
605
        break;
606
    case CODEC_ID_ADPCM_IMA_DK4:
607
        if (avctx->block_align != 0 && buf_size > avctx->block_align)
608
            buf_size = avctx->block_align;
609

    
610
        c->status[0].predictor = (src[0] | (src[1] << 8));
611
        c->status[0].step_index = src[2];
612
        src += 4;
613
        if(c->status[0].predictor & 0x8000)
614
            c->status[0].predictor -= 0x10000;
615
        *samples++ = c->status[0].predictor;
616
        if (st) {
617
            c->status[1].predictor = (src[0] | (src[1] << 8));
618
            c->status[1].step_index = src[2];
619
            src += 4;
620
            if(c->status[1].predictor & 0x8000)
621
                c->status[1].predictor -= 0x10000;
622
            *samples++ = c->status[1].predictor;
623
        }
624
        while (src < buf + buf_size) {
625

    
626
            /* take care of the top nibble (always left or mono channel) */
627
            *samples++ = adpcm_ima_expand_nibble(&c->status[0], 
628
                (src[0] >> 4) & 0x0F, 3);
629

    
630
            /* take care of the bottom nibble, which is right sample for
631
             * stereo, or another mono sample */
632
            if (st)
633
                *samples++ = adpcm_ima_expand_nibble(&c->status[1], 
634
                    src[0] & 0x0F, 3);
635
            else
636
                *samples++ = adpcm_ima_expand_nibble(&c->status[0], 
637
                    src[0] & 0x0F, 3);
638

    
639
            src++;
640
        }
641
        break;
642
    case CODEC_ID_ADPCM_IMA_DK3:
643
        if (avctx->block_align != 0 && buf_size > avctx->block_align)
644
            buf_size = avctx->block_align;
645

    
646
        c->status[0].predictor = (src[10] | (src[11] << 8));
647
        c->status[1].predictor = (src[12] | (src[13] << 8));
648
        c->status[0].step_index = src[14];
649
        c->status[1].step_index = src[15];
650
        /* sign extend the predictors */
651
        if(c->status[0].predictor & 0x8000)
652
            c->status[0].predictor -= 0x10000;
653
        if(c->status[1].predictor & 0x8000)
654
            c->status[1].predictor -= 0x10000;
655
        src += 16;
656
        diff_channel = c->status[1].predictor;
657

    
658
        /* the DK3_GET_NEXT_NIBBLE macro issues the break statement when
659
         * the buffer is consumed */
660
        while (1) {
661

    
662
            /* for this algorithm, c->status[0] is the sum channel and
663
             * c->status[1] is the diff channel */
664

    
665
            /* process the first predictor of the sum channel */
666
            DK3_GET_NEXT_NIBBLE();
667
            adpcm_ima_expand_nibble(&c->status[0], nibble, 3);
668

    
669
            /* process the diff channel predictor */
670
            DK3_GET_NEXT_NIBBLE();
671
            adpcm_ima_expand_nibble(&c->status[1], nibble, 3);
672

    
673
            /* process the first pair of stereo PCM samples */
674
            diff_channel = (diff_channel + c->status[1].predictor) / 2;
675
            *samples++ = c->status[0].predictor + c->status[1].predictor;
676
            *samples++ = c->status[0].predictor - c->status[1].predictor;
677

    
678
            /* process the second predictor of the sum channel */
679
            DK3_GET_NEXT_NIBBLE();
680
            adpcm_ima_expand_nibble(&c->status[0], nibble, 3);
681

    
682
            /* process the second pair of stereo PCM samples */
683
            diff_channel = (diff_channel + c->status[1].predictor) / 2;
684
            *samples++ = c->status[0].predictor + c->status[1].predictor;
685
            *samples++ = c->status[0].predictor - c->status[1].predictor;
686
        }
687
        break;
688
    case CODEC_ID_ADPCM_IMA_WS:
689
        /* no per-block initialization; just start decoding the data */
690
        while (src < buf + buf_size) {
691

    
692
            if (st) {
693
                *samples++ = adpcm_ima_expand_nibble(&c->status[0], 
694
                    (src[0] >> 4) & 0x0F, 3);
695
                *samples++ = adpcm_ima_expand_nibble(&c->status[1], 
696
                    src[0] & 0x0F, 3);
697
            } else {
698
                *samples++ = adpcm_ima_expand_nibble(&c->status[0], 
699
                    (src[0] >> 4) & 0x0F, 3);
700
                *samples++ = adpcm_ima_expand_nibble(&c->status[0], 
701
                    src[0] & 0x0F, 3);
702
            }
703

    
704
            src++;
705
        }
706
        break;
707
    case CODEC_ID_ADPCM_XA:
708
        c->status[0].sample1 = c->status[0].sample2 = 
709
        c->status[1].sample1 = c->status[1].sample2 = 0;
710
        while (buf_size >= 128) {
711
            xa_decode(samples, src, &c->status[0], &c->status[1], 
712
                avctx->channels);
713
            src += 128;
714
            samples += 28 * 8;
715
            buf_size -= 128;
716
        }
717
        break;
718
    default:
719
        *data_size = 0;
720
        return -1;
721
    }
722
    *data_size = (uint8_t *)samples - (uint8_t *)data;
723
    return src - buf;
724
}
725

    
726

    
727

    
728
#ifdef CONFIG_ENCODERS
729
#define ADPCM_ENCODER(id,name)                  \
730
AVCodec name ## _encoder = {                    \
731
    #name,                                      \
732
    CODEC_TYPE_AUDIO,                           \
733
    id,                                         \
734
    sizeof(ADPCMContext),                       \
735
    adpcm_encode_init,                          \
736
    adpcm_encode_frame,                         \
737
    adpcm_encode_close,                         \
738
    NULL,                                       \
739
};
740
#else
741
#define ADPCM_ENCODER(id,name)
742
#endif
743

    
744
#ifdef CONFIG_DECODERS
745
#define ADPCM_DECODER(id,name)                  \
746
AVCodec name ## _decoder = {                    \
747
    #name,                                      \
748
    CODEC_TYPE_AUDIO,                           \
749
    id,                                         \
750
    sizeof(ADPCMContext),                       \
751
    adpcm_decode_init,                          \
752
    NULL,                                       \
753
    NULL,                                       \
754
    adpcm_decode_frame,                         \
755
};
756
#else
757
#define ADPCM_DECODER(id,name)
758
#endif
759

    
760
#define ADPCM_CODEC(id, name)                   \
761
ADPCM_ENCODER(id,name) ADPCM_DECODER(id,name)
762

    
763
ADPCM_CODEC(CODEC_ID_ADPCM_IMA_QT, adpcm_ima_qt);
764
ADPCM_CODEC(CODEC_ID_ADPCM_IMA_WAV, adpcm_ima_wav);
765
ADPCM_CODEC(CODEC_ID_ADPCM_IMA_DK3, adpcm_ima_dk3);
766
ADPCM_CODEC(CODEC_ID_ADPCM_IMA_DK4, adpcm_ima_dk4);
767
ADPCM_CODEC(CODEC_ID_ADPCM_IMA_WS, adpcm_ima_ws);
768
ADPCM_CODEC(CODEC_ID_ADPCM_MS, adpcm_ms);
769
ADPCM_CODEC(CODEC_ID_ADPCM_4XM, adpcm_4xm);
770
ADPCM_CODEC(CODEC_ID_ADPCM_XA, adpcm_xa);
771
ADPCM_CODEC(CODEC_ID_ADPCM_ADX, adpcm_adx);
772

    
773
#undef ADPCM_CODEC