Statistics
| Branch: | Revision:

ffmpeg / libavcodec / sipr.c @ 2912e87a

History | View | Annotate | Download (18 KB)

1
/*
2
 * SIPR / ACELP.NET decoder
3
 *
4
 * Copyright (c) 2008 Vladimir Voroshilov
5
 * Copyright (c) 2009 Vitor Sessak
6
 *
7
 * This file is part of Libav.
8
 *
9
 * Libav is free software; you can redistribute it and/or
10
 * modify it under the terms of the GNU Lesser General Public
11
 * License as published by the Free Software Foundation; either
12
 * version 2.1 of the License, or (at your option) any later version.
13
 *
14
 * Libav is distributed in the hope that it will be useful,
15
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
16
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
17
 * Lesser General Public License for more details.
18
 *
19
 * You should have received a copy of the GNU Lesser General Public
20
 * License along with Libav; if not, write to the Free Software
21
 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
22
 */
23

    
24
#include <math.h>
25
#include <stdint.h>
26

    
27
#include "libavutil/mathematics.h"
28
#include "avcodec.h"
29
#define ALT_BITSTREAM_READER_LE
30
#include "get_bits.h"
31
#include "dsputil.h"
32

    
33
#include "lsp.h"
34
#include "celp_math.h"
35
#include "acelp_vectors.h"
36
#include "acelp_pitch_delay.h"
37
#include "acelp_filters.h"
38
#include "celp_filters.h"
39

    
40
#define MAX_SUBFRAME_COUNT   5
41

    
42
#include "sipr.h"
43
#include "siprdata.h"
44

    
45
typedef struct {
46
    const char *mode_name;
47
    uint16_t bits_per_frame;
48
    uint8_t subframe_count;
49
    uint8_t frames_per_packet;
50
    float pitch_sharp_factor;
51

    
52
    /* bitstream parameters */
53
    uint8_t number_of_fc_indexes;
54
    uint8_t ma_predictor_bits;  ///< size in bits of the switched MA predictor
55

    
56
    /** size in bits of the i-th stage vector of quantizer */
57
    uint8_t vq_indexes_bits[5];
58

    
59
    /** size in bits of the adaptive-codebook index for every subframe */
60
    uint8_t pitch_delay_bits[5];
61

    
62
    uint8_t gp_index_bits;
63
    uint8_t fc_index_bits[10]; ///< size in bits of the fixed codebook indexes
64
    uint8_t gc_index_bits;     ///< size in bits of the gain  codebook indexes
65
} SiprModeParam;
66

    
67
static const SiprModeParam modes[MODE_COUNT] = {
68
    [MODE_16k] = {
69
        .mode_name          = "16k",
70
        .bits_per_frame     = 160,
71
        .subframe_count     = SUBFRAME_COUNT_16k,
72
        .frames_per_packet  = 1,
73
        .pitch_sharp_factor = 0.00,
74

    
75
        .number_of_fc_indexes = 10,
76
        .ma_predictor_bits    = 1,
77
        .vq_indexes_bits      = {7, 8, 7, 7, 7},
78
        .pitch_delay_bits     = {9, 6},
79
        .gp_index_bits        = 4,
80
        .fc_index_bits        = {4, 5, 4, 5, 4, 5, 4, 5, 4, 5},
81
        .gc_index_bits        = 5
82
    },
83

    
84
    [MODE_8k5] = {
85
        .mode_name          = "8k5",
86
        .bits_per_frame     = 152,
87
        .subframe_count     = 3,
88
        .frames_per_packet  = 1,
89
        .pitch_sharp_factor = 0.8,
90

    
91
        .number_of_fc_indexes = 3,
92
        .ma_predictor_bits    = 0,
93
        .vq_indexes_bits      = {6, 7, 7, 7, 5},
94
        .pitch_delay_bits     = {8, 5, 5},
95
        .gp_index_bits        = 0,
96
        .fc_index_bits        = {9, 9, 9},
97
        .gc_index_bits        = 7
98
    },
99

    
100
    [MODE_6k5] = {
101
        .mode_name          = "6k5",
102
        .bits_per_frame     = 232,
103
        .subframe_count     = 3,
104
        .frames_per_packet  = 2,
105
        .pitch_sharp_factor = 0.8,
106

    
107
        .number_of_fc_indexes = 3,
108
        .ma_predictor_bits    = 0,
109
        .vq_indexes_bits      = {6, 7, 7, 7, 5},
110
        .pitch_delay_bits     = {8, 5, 5},
111
        .gp_index_bits        = 0,
112
        .fc_index_bits        = {5, 5, 5},
113
        .gc_index_bits        = 7
114
    },
115

    
116
    [MODE_5k0] = {
117
        .mode_name          = "5k0",
118
        .bits_per_frame     = 296,
119
        .subframe_count     = 5,
120
        .frames_per_packet  = 2,
121
        .pitch_sharp_factor = 0.85,
122

    
123
        .number_of_fc_indexes = 1,
124
        .ma_predictor_bits    = 0,
125
        .vq_indexes_bits      = {6, 7, 7, 7, 5},
126
        .pitch_delay_bits     = {8, 5, 8, 5, 5},
127
        .gp_index_bits        = 0,
128
        .fc_index_bits        = {10},
129
        .gc_index_bits        = 7
130
    }
131
};
132

    
133
const float ff_pow_0_5[] = {
134
    1.0/(1 <<  1), 1.0/(1 <<  2), 1.0/(1 <<  3), 1.0/(1 <<  4),
135
    1.0/(1 <<  5), 1.0/(1 <<  6), 1.0/(1 <<  7), 1.0/(1 <<  8),
136
    1.0/(1 <<  9), 1.0/(1 << 10), 1.0/(1 << 11), 1.0/(1 << 12),
137
    1.0/(1 << 13), 1.0/(1 << 14), 1.0/(1 << 15), 1.0/(1 << 16)
138
};
139

    
140
static void dequant(float *out, const int *idx, const float *cbs[])
141
{
142
    int i;
143
    int stride  = 2;
144
    int num_vec = 5;
145

    
146
    for (i = 0; i < num_vec; i++)
147
        memcpy(out + stride*i, cbs[i] + stride*idx[i], stride*sizeof(float));
148

    
149
}
150

    
151
static void lsf_decode_fp(float *lsfnew, float *lsf_history,
152
                          const SiprParameters *parm)
153
{
154
    int i;
155
    float lsf_tmp[LP_FILTER_ORDER];
156

    
157
    dequant(lsf_tmp, parm->vq_indexes, lsf_codebooks);
158

    
159
    for (i = 0; i < LP_FILTER_ORDER; i++)
160
        lsfnew[i] = lsf_history[i] * 0.33 + lsf_tmp[i] + mean_lsf[i];
161

    
162
    ff_sort_nearly_sorted_floats(lsfnew, LP_FILTER_ORDER - 1);
163

    
164
    /* Note that a minimum distance is not enforced between the last value and
165
       the previous one, contrary to what is done in ff_acelp_reorder_lsf() */
166
    ff_set_min_dist_lsf(lsfnew, LSFQ_DIFF_MIN, LP_FILTER_ORDER - 1);
167
    lsfnew[9] = FFMIN(lsfnew[LP_FILTER_ORDER - 1], 1.3 * M_PI);
168

    
169
    memcpy(lsf_history, lsf_tmp, LP_FILTER_ORDER * sizeof(*lsf_history));
170

    
171
    for (i = 0; i < LP_FILTER_ORDER - 1; i++)
172
        lsfnew[i] = cos(lsfnew[i]);
173
    lsfnew[LP_FILTER_ORDER - 1] *= 6.153848 / M_PI;
174
}
175

    
176
/** Apply pitch lag to the fixed vector (AMR section 6.1.2). */
177
static void pitch_sharpening(int pitch_lag_int, float beta,
178
                             float *fixed_vector)
179
{
180
    int i;
181

    
182
    for (i = pitch_lag_int; i < SUBFR_SIZE; i++)
183
        fixed_vector[i] += beta * fixed_vector[i - pitch_lag_int];
184
}
185

    
186
/**
187
 * Extract decoding parameters from the input bitstream.
188
 * @param parms          parameters structure
189
 * @param pgb            pointer to initialized GetBitContext structure
190
 */
191
static void decode_parameters(SiprParameters* parms, GetBitContext *pgb,
192
                              const SiprModeParam *p)
193
{
194
    int i, j;
195

    
196
    parms->ma_pred_switch           = get_bits(pgb, p->ma_predictor_bits);
197

    
198
    for (i = 0; i < 5; i++)
199
        parms->vq_indexes[i]        = get_bits(pgb, p->vq_indexes_bits[i]);
200

    
201
    for (i = 0; i < p->subframe_count; i++) {
202
        parms->pitch_delay[i]       = get_bits(pgb, p->pitch_delay_bits[i]);
203
        parms->gp_index[i]          = get_bits(pgb, p->gp_index_bits);
204

    
205
        for (j = 0; j < p->number_of_fc_indexes; j++)
206
            parms->fc_indexes[i][j] = get_bits(pgb, p->fc_index_bits[j]);
207

    
208
        parms->gc_index[i]          = get_bits(pgb, p->gc_index_bits);
209
    }
210
}
211

    
212
static void sipr_decode_lp(float *lsfnew, const float *lsfold, float *Az,
213
                           int num_subfr)
214
{
215
    double lsfint[LP_FILTER_ORDER];
216
    int i,j;
217
    float t, t0 = 1.0 / num_subfr;
218

    
219
    t = t0 * 0.5;
220
    for (i = 0; i < num_subfr; i++) {
221
        for (j = 0; j < LP_FILTER_ORDER; j++)
222
            lsfint[j] = lsfold[j] * (1 - t) + t * lsfnew[j];
223

    
224
        ff_amrwb_lsp2lpc(lsfint, Az, LP_FILTER_ORDER);
225
        Az += LP_FILTER_ORDER;
226
        t += t0;
227
    }
228
}
229

    
230
/**
231
 * Evaluate the adaptive impulse response.
232
 */
233
static void eval_ir(const float *Az, int pitch_lag, float *freq,
234
                    float pitch_sharp_factor)
235
{
236
    float tmp1[SUBFR_SIZE+1], tmp2[LP_FILTER_ORDER+1];
237
    int i;
238

    
239
    tmp1[0] = 1.;
240
    for (i = 0; i < LP_FILTER_ORDER; i++) {
241
        tmp1[i+1] = Az[i] * ff_pow_0_55[i];
242
        tmp2[i  ] = Az[i] * ff_pow_0_7 [i];
243
    }
244
    memset(tmp1 + 11, 0, 37 * sizeof(float));
245

    
246
    ff_celp_lp_synthesis_filterf(freq, tmp2, tmp1, SUBFR_SIZE,
247
                                 LP_FILTER_ORDER);
248

    
249
    pitch_sharpening(pitch_lag, pitch_sharp_factor, freq);
250
}
251

    
252
/**
253
 * Evaluate the convolution of a vector with a sparse vector.
254
 */
255
static void convolute_with_sparse(float *out, const AMRFixed *pulses,
256
                                  const float *shape, int length)
257
{
258
    int i, j;
259

    
260
    memset(out, 0, length*sizeof(float));
261
    for (i = 0; i < pulses->n; i++)
262
        for (j = pulses->x[i]; j < length; j++)
263
            out[j] += pulses->y[i] * shape[j - pulses->x[i]];
264
}
265

    
266
/**
267
 * Apply postfilter, very similar to AMR one.
268
 */
269
static void postfilter_5k0(SiprContext *ctx, const float *lpc, float *samples)
270
{
271
    float buf[SUBFR_SIZE + LP_FILTER_ORDER];
272
    float *pole_out = buf + LP_FILTER_ORDER;
273
    float lpc_n[LP_FILTER_ORDER];
274
    float lpc_d[LP_FILTER_ORDER];
275
    int i;
276

    
277
    for (i = 0; i < LP_FILTER_ORDER; i++) {
278
        lpc_d[i] = lpc[i] * ff_pow_0_75[i];
279
        lpc_n[i] = lpc[i] * ff_pow_0_5 [i];
280
    };
281

    
282
    memcpy(pole_out - LP_FILTER_ORDER, ctx->postfilter_mem,
283
           LP_FILTER_ORDER*sizeof(float));
284

    
285
    ff_celp_lp_synthesis_filterf(pole_out, lpc_d, samples, SUBFR_SIZE,
286
                                 LP_FILTER_ORDER);
287

    
288
    memcpy(ctx->postfilter_mem, pole_out + SUBFR_SIZE - LP_FILTER_ORDER,
289
           LP_FILTER_ORDER*sizeof(float));
290

    
291
    ff_tilt_compensation(&ctx->tilt_mem, 0.4, pole_out, SUBFR_SIZE);
292

    
293
    memcpy(pole_out - LP_FILTER_ORDER, ctx->postfilter_mem5k0,
294
           LP_FILTER_ORDER*sizeof(*pole_out));
295

    
296
    memcpy(ctx->postfilter_mem5k0, pole_out + SUBFR_SIZE - LP_FILTER_ORDER,
297
           LP_FILTER_ORDER*sizeof(*pole_out));
298

    
299
    ff_celp_lp_zero_synthesis_filterf(samples, lpc_n, pole_out, SUBFR_SIZE,
300
                                      LP_FILTER_ORDER);
301

    
302
}
303

    
304
static void decode_fixed_sparse(AMRFixed *fixed_sparse, const int16_t *pulses,
305
                                SiprMode mode, int low_gain)
306
{
307
    int i;
308

    
309
    switch (mode) {
310
    case MODE_6k5:
311
        for (i = 0; i < 3; i++) {
312
            fixed_sparse->x[i] = 3 * (pulses[i] & 0xf) + i;
313
            fixed_sparse->y[i] = pulses[i] & 0x10 ? -1 : 1;
314
        }
315
        fixed_sparse->n = 3;
316
        break;
317
    case MODE_8k5:
318
        for (i = 0; i < 3; i++) {
319
            fixed_sparse->x[2*i    ] = 3 * ((pulses[i] >> 4) & 0xf) + i;
320
            fixed_sparse->x[2*i + 1] = 3 * ( pulses[i]       & 0xf) + i;
321

    
322
            fixed_sparse->y[2*i    ] = (pulses[i] & 0x100) ? -1.0: 1.0;
323

    
324
            fixed_sparse->y[2*i + 1] =
325
                (fixed_sparse->x[2*i + 1] < fixed_sparse->x[2*i]) ?
326
                -fixed_sparse->y[2*i    ] : fixed_sparse->y[2*i];
327
        }
328

    
329
        fixed_sparse->n = 6;
330
        break;
331
    case MODE_5k0:
332
    default:
333
        if (low_gain) {
334
            int offset = (pulses[0] & 0x200) ? 2 : 0;
335
            int val = pulses[0];
336

    
337
            for (i = 0; i < 3; i++) {
338
                int index = (val & 0x7) * 6 + 4 - i*2;
339

    
340
                fixed_sparse->y[i] = (offset + index) & 0x3 ? -1 : 1;
341
                fixed_sparse->x[i] = index;
342

    
343
                val >>= 3;
344
            }
345
            fixed_sparse->n = 3;
346
        } else {
347
            int pulse_subset = (pulses[0] >> 8) & 1;
348

    
349
            fixed_sparse->x[0] = ((pulses[0] >> 4) & 15) * 3 + pulse_subset;
350
            fixed_sparse->x[1] = ( pulses[0]       & 15) * 3 + pulse_subset + 1;
351

    
352
            fixed_sparse->y[0] = pulses[0] & 0x200 ? -1 : 1;
353
            fixed_sparse->y[1] = -fixed_sparse->y[0];
354
            fixed_sparse->n = 2;
355
        }
356
        break;
357
    }
358
}
359

    
360
static void decode_frame(SiprContext *ctx, SiprParameters *params,
361
                         float *out_data)
362
{
363
    int i, j;
364
    int subframe_count = modes[ctx->mode].subframe_count;
365
    int frame_size = subframe_count * SUBFR_SIZE;
366
    float Az[LP_FILTER_ORDER * MAX_SUBFRAME_COUNT];
367
    float *excitation;
368
    float ir_buf[SUBFR_SIZE + LP_FILTER_ORDER];
369
    float lsf_new[LP_FILTER_ORDER];
370
    float *impulse_response = ir_buf + LP_FILTER_ORDER;
371
    float *synth = ctx->synth_buf + 16; // 16 instead of LP_FILTER_ORDER for
372
                                        // memory alignment
373
    int t0_first = 0;
374
    AMRFixed fixed_cb;
375

    
376
    memset(ir_buf, 0, LP_FILTER_ORDER * sizeof(float));
377
    lsf_decode_fp(lsf_new, ctx->lsf_history, params);
378

    
379
    sipr_decode_lp(lsf_new, ctx->lsp_history, Az, subframe_count);
380

    
381
    memcpy(ctx->lsp_history, lsf_new, LP_FILTER_ORDER * sizeof(float));
382

    
383
    excitation = ctx->excitation + PITCH_DELAY_MAX + L_INTERPOL;
384

    
385
    for (i = 0; i < subframe_count; i++) {
386
        float *pAz = Az + i*LP_FILTER_ORDER;
387
        float fixed_vector[SUBFR_SIZE];
388
        int T0,T0_frac;
389
        float pitch_gain, gain_code, avg_energy;
390

    
391
        ff_decode_pitch_lag(&T0, &T0_frac, params->pitch_delay[i], t0_first, i,
392
                            ctx->mode == MODE_5k0, 6);
393

    
394
        if (i == 0 || (i == 2 && ctx->mode == MODE_5k0))
395
            t0_first = T0;
396

    
397
        ff_acelp_interpolatef(excitation, excitation - T0 + (T0_frac <= 0),
398
                              ff_b60_sinc, 6,
399
                              2 * ((2 + T0_frac)%3 + 1), LP_FILTER_ORDER,
400
                              SUBFR_SIZE);
401

    
402
        decode_fixed_sparse(&fixed_cb, params->fc_indexes[i], ctx->mode,
403
                            ctx->past_pitch_gain < 0.8);
404

    
405
        eval_ir(pAz, T0, impulse_response, modes[ctx->mode].pitch_sharp_factor);
406

    
407
        convolute_with_sparse(fixed_vector, &fixed_cb, impulse_response,
408
                              SUBFR_SIZE);
409

    
410
        avg_energy =
411
            (0.01 + ff_dot_productf(fixed_vector, fixed_vector, SUBFR_SIZE))/
412
                SUBFR_SIZE;
413

    
414
        ctx->past_pitch_gain = pitch_gain = gain_cb[params->gc_index[i]][0];
415

    
416
        gain_code = ff_amr_set_fixed_gain(gain_cb[params->gc_index[i]][1],
417
                                          avg_energy, ctx->energy_history,
418
                                          34 - 15.0/(0.05*M_LN10/M_LN2),
419
                                          pred);
420

    
421
        ff_weighted_vector_sumf(excitation, excitation, fixed_vector,
422
                                pitch_gain, gain_code, SUBFR_SIZE);
423

    
424
        pitch_gain *= 0.5 * pitch_gain;
425
        pitch_gain = FFMIN(pitch_gain, 0.4);
426

    
427
        ctx->gain_mem = 0.7 * ctx->gain_mem + 0.3 * pitch_gain;
428
        ctx->gain_mem = FFMIN(ctx->gain_mem, pitch_gain);
429
        gain_code *= ctx->gain_mem;
430

    
431
        for (j = 0; j < SUBFR_SIZE; j++)
432
            fixed_vector[j] = excitation[j] - gain_code * fixed_vector[j];
433

    
434
        if (ctx->mode == MODE_5k0) {
435
            postfilter_5k0(ctx, pAz, fixed_vector);
436

    
437
            ff_celp_lp_synthesis_filterf(ctx->postfilter_syn5k0 + LP_FILTER_ORDER + i*SUBFR_SIZE,
438
                                         pAz, excitation, SUBFR_SIZE,
439
                                         LP_FILTER_ORDER);
440
        }
441

    
442
        ff_celp_lp_synthesis_filterf(synth + i*SUBFR_SIZE, pAz, fixed_vector,
443
                                     SUBFR_SIZE, LP_FILTER_ORDER);
444

    
445
        excitation += SUBFR_SIZE;
446
    }
447

    
448
    memcpy(synth - LP_FILTER_ORDER, synth + frame_size - LP_FILTER_ORDER,
449
           LP_FILTER_ORDER * sizeof(float));
450

    
451
    if (ctx->mode == MODE_5k0) {
452
        for (i = 0; i < subframe_count; i++) {
453
            float energy = ff_dot_productf(ctx->postfilter_syn5k0 + LP_FILTER_ORDER + i*SUBFR_SIZE,
454
                                           ctx->postfilter_syn5k0 + LP_FILTER_ORDER + i*SUBFR_SIZE,
455
                                           SUBFR_SIZE);
456
            ff_adaptive_gain_control(&synth[i * SUBFR_SIZE],
457
                                     &synth[i * SUBFR_SIZE], energy,
458
                                     SUBFR_SIZE, 0.9, &ctx->postfilter_agc);
459
        }
460

    
461
        memcpy(ctx->postfilter_syn5k0, ctx->postfilter_syn5k0 + frame_size,
462
               LP_FILTER_ORDER*sizeof(float));
463
    }
464
    memcpy(ctx->excitation, excitation - PITCH_DELAY_MAX - L_INTERPOL,
465
           (PITCH_DELAY_MAX + L_INTERPOL) * sizeof(float));
466

    
467
    ff_acelp_apply_order_2_transfer_function(out_data, synth,
468
                                             (const float[2]) {-1.99997   , 1.000000000},
469
                                             (const float[2]) {-1.93307352, 0.935891986},
470
                                             0.939805806,
471
                                             ctx->highpass_filt_mem,
472
                                             frame_size);
473
}
474

    
475
static av_cold int sipr_decoder_init(AVCodecContext * avctx)
476
{
477
    SiprContext *ctx = avctx->priv_data;
478
    int i;
479

    
480
    if      (avctx->bit_rate > 12200) ctx->mode = MODE_16k;
481
    else if (avctx->bit_rate > 7500 ) ctx->mode = MODE_8k5;
482
    else if (avctx->bit_rate > 5750 ) ctx->mode = MODE_6k5;
483
    else                              ctx->mode = MODE_5k0;
484

    
485
    av_log(avctx, AV_LOG_DEBUG, "Mode: %s\n", modes[ctx->mode].mode_name);
486

    
487
    if (ctx->mode == MODE_16k)
488
        ff_sipr_init_16k(ctx);
489

    
490
    for (i = 0; i < LP_FILTER_ORDER; i++)
491
        ctx->lsp_history[i] = cos((i+1) * M_PI / (LP_FILTER_ORDER + 1));
492

    
493
    for (i = 0; i < 4; i++)
494
        ctx->energy_history[i] = -14;
495

    
496
    avctx->sample_fmt = AV_SAMPLE_FMT_FLT;
497

    
498
    dsputil_init(&ctx->dsp, avctx);
499

    
500
    return 0;
501
}
502

    
503
static int sipr_decode_frame(AVCodecContext *avctx, void *datap,
504
                             int *data_size, AVPacket *avpkt)
505
{
506
    SiprContext *ctx = avctx->priv_data;
507
    const uint8_t *buf=avpkt->data;
508
    SiprParameters parm;
509
    const SiprModeParam *mode_par = &modes[ctx->mode];
510
    GetBitContext gb;
511
    float *data = datap;
512
    int subframe_size = ctx->mode == MODE_16k ? L_SUBFR_16k : SUBFR_SIZE;
513
    int i;
514

    
515
    ctx->avctx = avctx;
516
    if (avpkt->size < (mode_par->bits_per_frame >> 3)) {
517
        av_log(avctx, AV_LOG_ERROR,
518
               "Error processing packet: packet size (%d) too small\n",
519
               avpkt->size);
520

    
521
        *data_size = 0;
522
        return -1;
523
    }
524
    if (*data_size < subframe_size * mode_par->subframe_count * sizeof(float)) {
525
        av_log(avctx, AV_LOG_ERROR,
526
               "Error processing packet: output buffer (%d) too small\n",
527
               *data_size);
528

    
529
        *data_size = 0;
530
        return -1;
531
    }
532

    
533
    init_get_bits(&gb, buf, mode_par->bits_per_frame);
534

    
535
    for (i = 0; i < mode_par->frames_per_packet; i++) {
536
        decode_parameters(&parm, &gb, mode_par);
537

    
538
        if (ctx->mode == MODE_16k)
539
            ff_sipr_decode_frame_16k(ctx, &parm, data);
540
        else
541
            decode_frame(ctx, &parm, data);
542

    
543
        data += subframe_size * mode_par->subframe_count;
544
    }
545

    
546
    *data_size = mode_par->frames_per_packet * subframe_size *
547
        mode_par->subframe_count * sizeof(float);
548

    
549
    return mode_par->bits_per_frame >> 3;
550
}
551

    
552
AVCodec ff_sipr_decoder = {
553
    "sipr",
554
    AVMEDIA_TYPE_AUDIO,
555
    CODEC_ID_SIPR,
556
    sizeof(SiprContext),
557
    sipr_decoder_init,
558
    NULL,
559
    NULL,
560
    sipr_decode_frame,
561
    .long_name = NULL_IF_CONFIG_SMALL("RealAudio SIPR / ACELP.NET"),
562
};