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libavcodec/sipr.c

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00001 /*
00002  * SIPR / ACELP.NET decoder
00003  *
00004  * Copyright (c) 2008 Vladimir Voroshilov
00005  * Copyright (c) 2009 Vitor Sessak
00006  *
00007  * This file is part of FFmpeg.
00008  *
00009  * FFmpeg is free software; you can redistribute it and/or
00010  * modify it under the terms of the GNU Lesser General Public
00011  * License as published by the Free Software Foundation; either
00012  * version 2.1 of the License, or (at your option) any later version.
00013  *
00014  * FFmpeg is distributed in the hope that it will be useful,
00015  * but WITHOUT ANY WARRANTY; without even the implied warranty of
00016  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
00017  * Lesser General Public License for more details.
00018  *
00019  * You should have received a copy of the GNU Lesser General Public
00020  * License along with FFmpeg; if not, write to the Free Software
00021  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
00022  */
00023 
00024 #include <math.h>
00025 #include <stdint.h>
00026 
00027 #include "libavutil/mathematics.h"
00028 #include "avcodec.h"
00029 #define ALT_BITSTREAM_READER_LE
00030 #include "get_bits.h"
00031 #include "dsputil.h"
00032 
00033 #include "lsp.h"
00034 #include "celp_math.h"
00035 #include "acelp_vectors.h"
00036 #include "acelp_pitch_delay.h"
00037 #include "acelp_filters.h"
00038 #include "celp_filters.h"
00039 
00040 #define MAX_SUBFRAME_COUNT   5
00041 
00042 #include "sipr.h"
00043 #include "siprdata.h"
00044 
00045 typedef struct {
00046     const char *mode_name;
00047     uint16_t bits_per_frame;
00048     uint8_t subframe_count;
00049     uint8_t frames_per_packet;
00050     float pitch_sharp_factor;
00051 
00052     /* bitstream parameters */
00053     uint8_t number_of_fc_indexes;
00054     uint8_t ma_predictor_bits;  
00055 
00057     uint8_t vq_indexes_bits[5];
00058 
00060     uint8_t pitch_delay_bits[5];
00061 
00062     uint8_t gp_index_bits;
00063     uint8_t fc_index_bits[10]; 
00064     uint8_t gc_index_bits;     
00065 } SiprModeParam;
00066 
00067 static const SiprModeParam modes[MODE_COUNT] = {
00068     [MODE_16k] = {
00069         .mode_name          = "16k",
00070         .bits_per_frame     = 160,
00071         .subframe_count     = SUBFRAME_COUNT_16k,
00072         .frames_per_packet  = 1,
00073         .pitch_sharp_factor = 0.00,
00074 
00075         .number_of_fc_indexes = 10,
00076         .ma_predictor_bits    = 1,
00077         .vq_indexes_bits      = {7, 8, 7, 7, 7},
00078         .pitch_delay_bits     = {9, 6},
00079         .gp_index_bits        = 4,
00080         .fc_index_bits        = {4, 5, 4, 5, 4, 5, 4, 5, 4, 5},
00081         .gc_index_bits        = 5
00082     },
00083 
00084     [MODE_8k5] = {
00085         .mode_name          = "8k5",
00086         .bits_per_frame     = 152,
00087         .subframe_count     = 3,
00088         .frames_per_packet  = 1,
00089         .pitch_sharp_factor = 0.8,
00090 
00091         .number_of_fc_indexes = 3,
00092         .ma_predictor_bits    = 0,
00093         .vq_indexes_bits      = {6, 7, 7, 7, 5},
00094         .pitch_delay_bits     = {8, 5, 5},
00095         .gp_index_bits        = 0,
00096         .fc_index_bits        = {9, 9, 9},
00097         .gc_index_bits        = 7
00098     },
00099 
00100     [MODE_6k5] = {
00101         .mode_name          = "6k5",
00102         .bits_per_frame     = 232,
00103         .subframe_count     = 3,
00104         .frames_per_packet  = 2,
00105         .pitch_sharp_factor = 0.8,
00106 
00107         .number_of_fc_indexes = 3,
00108         .ma_predictor_bits    = 0,
00109         .vq_indexes_bits      = {6, 7, 7, 7, 5},
00110         .pitch_delay_bits     = {8, 5, 5},
00111         .gp_index_bits        = 0,
00112         .fc_index_bits        = {5, 5, 5},
00113         .gc_index_bits        = 7
00114     },
00115 
00116     [MODE_5k0] = {
00117         .mode_name          = "5k0",
00118         .bits_per_frame     = 296,
00119         .subframe_count     = 5,
00120         .frames_per_packet  = 2,
00121         .pitch_sharp_factor = 0.85,
00122 
00123         .number_of_fc_indexes = 1,
00124         .ma_predictor_bits    = 0,
00125         .vq_indexes_bits      = {6, 7, 7, 7, 5},
00126         .pitch_delay_bits     = {8, 5, 8, 5, 5},
00127         .gp_index_bits        = 0,
00128         .fc_index_bits        = {10},
00129         .gc_index_bits        = 7
00130     }
00131 };
00132 
00133 const float ff_pow_0_5[] = {
00134     1.0/(1 <<  1), 1.0/(1 <<  2), 1.0/(1 <<  3), 1.0/(1 <<  4),
00135     1.0/(1 <<  5), 1.0/(1 <<  6), 1.0/(1 <<  7), 1.0/(1 <<  8),
00136     1.0/(1 <<  9), 1.0/(1 << 10), 1.0/(1 << 11), 1.0/(1 << 12),
00137     1.0/(1 << 13), 1.0/(1 << 14), 1.0/(1 << 15), 1.0/(1 << 16)
00138 };
00139 
00140 static void dequant(float *out, const int *idx, const float *cbs[])
00141 {
00142     int i;
00143     int stride  = 2;
00144     int num_vec = 5;
00145 
00146     for (i = 0; i < num_vec; i++)
00147         memcpy(out + stride*i, cbs[i] + stride*idx[i], stride*sizeof(float));
00148 
00149 }
00150 
00151 static void lsf_decode_fp(float *lsfnew, float *lsf_history,
00152                           const SiprParameters *parm)
00153 {
00154     int i;
00155     float lsf_tmp[LP_FILTER_ORDER];
00156 
00157     dequant(lsf_tmp, parm->vq_indexes, lsf_codebooks);
00158 
00159     for (i = 0; i < LP_FILTER_ORDER; i++)
00160         lsfnew[i] = lsf_history[i] * 0.33 + lsf_tmp[i] + mean_lsf[i];
00161 
00162     ff_sort_nearly_sorted_floats(lsfnew, LP_FILTER_ORDER - 1);
00163 
00164     /* Note that a minimum distance is not enforced between the last value and
00165        the previous one, contrary to what is done in ff_acelp_reorder_lsf() */
00166     ff_set_min_dist_lsf(lsfnew, LSFQ_DIFF_MIN, LP_FILTER_ORDER - 1);
00167     lsfnew[9] = FFMIN(lsfnew[LP_FILTER_ORDER - 1], 1.3 * M_PI);
00168 
00169     memcpy(lsf_history, lsf_tmp, LP_FILTER_ORDER * sizeof(*lsf_history));
00170 
00171     for (i = 0; i < LP_FILTER_ORDER - 1; i++)
00172         lsfnew[i] = cos(lsfnew[i]);
00173     lsfnew[LP_FILTER_ORDER - 1] *= 6.153848 / M_PI;
00174 }
00175 
00177 static void pitch_sharpening(int pitch_lag_int, float beta,
00178                              float *fixed_vector)
00179 {
00180     int i;
00181 
00182     for (i = pitch_lag_int; i < SUBFR_SIZE; i++)
00183         fixed_vector[i] += beta * fixed_vector[i - pitch_lag_int];
00184 }
00185 
00191 static void decode_parameters(SiprParameters* parms, GetBitContext *pgb,
00192                               const SiprModeParam *p)
00193 {
00194     int i, j;
00195 
00196     parms->ma_pred_switch           = get_bits(pgb, p->ma_predictor_bits);
00197 
00198     for (i = 0; i < 5; i++)
00199         parms->vq_indexes[i]        = get_bits(pgb, p->vq_indexes_bits[i]);
00200 
00201     for (i = 0; i < p->subframe_count; i++) {
00202         parms->pitch_delay[i]       = get_bits(pgb, p->pitch_delay_bits[i]);
00203         parms->gp_index[i]          = get_bits(pgb, p->gp_index_bits);
00204 
00205         for (j = 0; j < p->number_of_fc_indexes; j++)
00206             parms->fc_indexes[i][j] = get_bits(pgb, p->fc_index_bits[j]);
00207 
00208         parms->gc_index[i]          = get_bits(pgb, p->gc_index_bits);
00209     }
00210 }
00211 
00212 static void lsp2lpc_sipr(const double *lsp, float *Az)
00213 {
00214     int lp_half_order = LP_FILTER_ORDER >> 1;
00215     double buf[(LP_FILTER_ORDER >> 1) + 1];
00216     double pa[(LP_FILTER_ORDER >> 1) + 1];
00217     double *qa = buf + 1;
00218     int i,j;
00219 
00220     qa[-1] = 0.0;
00221 
00222     ff_lsp2polyf(lsp    , pa, lp_half_order    );
00223     ff_lsp2polyf(lsp + 1, qa, lp_half_order - 1);
00224 
00225     for (i = 1, j = LP_FILTER_ORDER - 1; i < lp_half_order; i++, j--) {
00226         double paf =  pa[i]            * (1 + lsp[LP_FILTER_ORDER - 1]);
00227         double qaf = (qa[i] - qa[i-2]) * (1 - lsp[LP_FILTER_ORDER - 1]);
00228         Az[i-1]  = (paf + qaf) * 0.5;
00229         Az[j-1]  = (paf - qaf) * 0.5;
00230     }
00231 
00232     Az[lp_half_order - 1] = (1.0 + lsp[LP_FILTER_ORDER - 1]) *
00233         pa[lp_half_order] * 0.5;
00234 
00235     Az[LP_FILTER_ORDER - 1] = lsp[LP_FILTER_ORDER - 1];
00236 }
00237 
00238 static void sipr_decode_lp(float *lsfnew, const float *lsfold, float *Az,
00239                            int num_subfr)
00240 {
00241     double lsfint[LP_FILTER_ORDER];
00242     int i,j;
00243     float t, t0 = 1.0 / num_subfr;
00244 
00245     t = t0 * 0.5;
00246     for (i = 0; i < num_subfr; i++) {
00247         for (j = 0; j < LP_FILTER_ORDER; j++)
00248             lsfint[j] = lsfold[j] * (1 - t) + t * lsfnew[j];
00249 
00250         lsp2lpc_sipr(lsfint, Az);
00251         Az += LP_FILTER_ORDER;
00252         t += t0;
00253     }
00254 }
00255 
00259 static void eval_ir(const float *Az, int pitch_lag, float *freq,
00260                     float pitch_sharp_factor)
00261 {
00262     float tmp1[SUBFR_SIZE+1], tmp2[LP_FILTER_ORDER+1];
00263     int i;
00264 
00265     tmp1[0] = 1.;
00266     for (i = 0; i < LP_FILTER_ORDER; i++) {
00267         tmp1[i+1] = Az[i] * ff_pow_0_55[i];
00268         tmp2[i  ] = Az[i] * ff_pow_0_7 [i];
00269     }
00270     memset(tmp1 + 11, 0, 37 * sizeof(float));
00271 
00272     ff_celp_lp_synthesis_filterf(freq, tmp2, tmp1, SUBFR_SIZE,
00273                                  LP_FILTER_ORDER);
00274 
00275     pitch_sharpening(pitch_lag, pitch_sharp_factor, freq);
00276 }
00277 
00281 static void convolute_with_sparse(float *out, const AMRFixed *pulses,
00282                                   const float *shape, int length)
00283 {
00284     int i, j;
00285 
00286     memset(out, 0, length*sizeof(float));
00287     for (i = 0; i < pulses->n; i++)
00288         for (j = pulses->x[i]; j < length; j++)
00289             out[j] += pulses->y[i] * shape[j - pulses->x[i]];
00290 }
00291 
00295 static void postfilter_5k0(SiprContext *ctx, const float *lpc, float *samples)
00296 {
00297     float buf[SUBFR_SIZE + LP_FILTER_ORDER];
00298     float *pole_out = buf + LP_FILTER_ORDER;
00299     float lpc_n[LP_FILTER_ORDER];
00300     float lpc_d[LP_FILTER_ORDER];
00301     int i;
00302 
00303     for (i = 0; i < LP_FILTER_ORDER; i++) {
00304         lpc_d[i] = lpc[i] * ff_pow_0_75[i];
00305         lpc_n[i] = lpc[i] * ff_pow_0_5 [i];
00306     };
00307 
00308     memcpy(pole_out - LP_FILTER_ORDER, ctx->postfilter_mem,
00309            LP_FILTER_ORDER*sizeof(float));
00310 
00311     ff_celp_lp_synthesis_filterf(pole_out, lpc_d, samples, SUBFR_SIZE,
00312                                  LP_FILTER_ORDER);
00313 
00314     memcpy(ctx->postfilter_mem, pole_out + SUBFR_SIZE - LP_FILTER_ORDER,
00315            LP_FILTER_ORDER*sizeof(float));
00316 
00317     ff_tilt_compensation(&ctx->tilt_mem, 0.4, pole_out, SUBFR_SIZE);
00318 
00319     memcpy(pole_out - LP_FILTER_ORDER, ctx->postfilter_mem5k0,
00320            LP_FILTER_ORDER*sizeof(*pole_out));
00321 
00322     memcpy(ctx->postfilter_mem5k0, pole_out + SUBFR_SIZE - LP_FILTER_ORDER,
00323            LP_FILTER_ORDER*sizeof(*pole_out));
00324 
00325     ff_celp_lp_zero_synthesis_filterf(samples, lpc_n, pole_out, SUBFR_SIZE,
00326                                       LP_FILTER_ORDER);
00327 
00328 }
00329 
00330 static void decode_fixed_sparse(AMRFixed *fixed_sparse, const int16_t *pulses,
00331                                 SiprMode mode, int low_gain)
00332 {
00333     int i;
00334 
00335     switch (mode) {
00336     case MODE_6k5:
00337         for (i = 0; i < 3; i++) {
00338             fixed_sparse->x[i] = 3 * (pulses[i] & 0xf) + i;
00339             fixed_sparse->y[i] = pulses[i] & 0x10 ? -1 : 1;
00340         }
00341         fixed_sparse->n = 3;
00342         break;
00343     case MODE_8k5:
00344         for (i = 0; i < 3; i++) {
00345             fixed_sparse->x[2*i    ] = 3 * ((pulses[i] >> 4) & 0xf) + i;
00346             fixed_sparse->x[2*i + 1] = 3 * ( pulses[i]       & 0xf) + i;
00347 
00348             fixed_sparse->y[2*i    ] = (pulses[i] & 0x100) ? -1.0: 1.0;
00349 
00350             fixed_sparse->y[2*i + 1] =
00351                 (fixed_sparse->x[2*i + 1] < fixed_sparse->x[2*i]) ?
00352                 -fixed_sparse->y[2*i    ] : fixed_sparse->y[2*i];
00353         }
00354 
00355         fixed_sparse->n = 6;
00356         break;
00357     case MODE_5k0:
00358     default:
00359         if (low_gain) {
00360             int offset = (pulses[0] & 0x200) ? 2 : 0;
00361             int val = pulses[0];
00362 
00363             for (i = 0; i < 3; i++) {
00364                 int index = (val & 0x7) * 6 + 4 - i*2;
00365 
00366                 fixed_sparse->y[i] = (offset + index) & 0x3 ? -1 : 1;
00367                 fixed_sparse->x[i] = index;
00368 
00369                 val >>= 3;
00370             }
00371             fixed_sparse->n = 3;
00372         } else {
00373             int pulse_subset = (pulses[0] >> 8) & 1;
00374 
00375             fixed_sparse->x[0] = ((pulses[0] >> 4) & 15) * 3 + pulse_subset;
00376             fixed_sparse->x[1] = ( pulses[0]       & 15) * 3 + pulse_subset + 1;
00377 
00378             fixed_sparse->y[0] = pulses[0] & 0x200 ? -1 : 1;
00379             fixed_sparse->y[1] = -fixed_sparse->y[0];
00380             fixed_sparse->n = 2;
00381         }
00382         break;
00383     }
00384 }
00385 
00386 static void decode_frame(SiprContext *ctx, SiprParameters *params,
00387                          float *out_data)
00388 {
00389     int i, j;
00390     int subframe_count = modes[ctx->mode].subframe_count;
00391     int frame_size = subframe_count * SUBFR_SIZE;
00392     float Az[LP_FILTER_ORDER * MAX_SUBFRAME_COUNT];
00393     float *excitation;
00394     float ir_buf[SUBFR_SIZE + LP_FILTER_ORDER];
00395     float lsf_new[LP_FILTER_ORDER];
00396     float *impulse_response = ir_buf + LP_FILTER_ORDER;
00397     float *synth = ctx->synth_buf + 16; // 16 instead of LP_FILTER_ORDER for
00398                                         // memory alignment
00399     int t0_first = 0;
00400     AMRFixed fixed_cb;
00401 
00402     memset(ir_buf, 0, LP_FILTER_ORDER * sizeof(float));
00403     lsf_decode_fp(lsf_new, ctx->lsf_history, params);
00404 
00405     sipr_decode_lp(lsf_new, ctx->lsp_history, Az, subframe_count);
00406 
00407     memcpy(ctx->lsp_history, lsf_new, LP_FILTER_ORDER * sizeof(float));
00408 
00409     excitation = ctx->excitation + PITCH_DELAY_MAX + L_INTERPOL;
00410 
00411     for (i = 0; i < subframe_count; i++) {
00412         float *pAz = Az + i*LP_FILTER_ORDER;
00413         float fixed_vector[SUBFR_SIZE];
00414         int T0,T0_frac;
00415         float pitch_gain, gain_code, avg_energy;
00416 
00417         ff_decode_pitch_lag(&T0, &T0_frac, params->pitch_delay[i], t0_first, i,
00418                             ctx->mode == MODE_5k0, 6);
00419 
00420         if (i == 0 || (i == 2 && ctx->mode == MODE_5k0))
00421             t0_first = T0;
00422 
00423         ff_acelp_interpolatef(excitation, excitation - T0 + (T0_frac <= 0),
00424                               ff_b60_sinc, 6,
00425                               2 * ((2 + T0_frac)%3 + 1), LP_FILTER_ORDER,
00426                               SUBFR_SIZE);
00427 
00428         decode_fixed_sparse(&fixed_cb, params->fc_indexes[i], ctx->mode,
00429                             ctx->past_pitch_gain < 0.8);
00430 
00431         eval_ir(pAz, T0, impulse_response, modes[ctx->mode].pitch_sharp_factor);
00432 
00433         convolute_with_sparse(fixed_vector, &fixed_cb, impulse_response,
00434                               SUBFR_SIZE);
00435 
00436         avg_energy =
00437             (0.01 + ff_dot_productf(fixed_vector, fixed_vector, SUBFR_SIZE))/
00438                 SUBFR_SIZE;
00439 
00440         ctx->past_pitch_gain = pitch_gain = gain_cb[params->gc_index[i]][0];
00441 
00442         gain_code = ff_amr_set_fixed_gain(gain_cb[params->gc_index[i]][1],
00443                                           avg_energy, ctx->energy_history,
00444                                           34 - 15.0/(0.05*M_LN10/M_LN2),
00445                                           pred);
00446 
00447         ff_weighted_vector_sumf(excitation, excitation, fixed_vector,
00448                                 pitch_gain, gain_code, SUBFR_SIZE);
00449 
00450         pitch_gain *= 0.5 * pitch_gain;
00451         pitch_gain = FFMIN(pitch_gain, 0.4);
00452 
00453         ctx->gain_mem = 0.7 * ctx->gain_mem + 0.3 * pitch_gain;
00454         ctx->gain_mem = FFMIN(ctx->gain_mem, pitch_gain);
00455         gain_code *= ctx->gain_mem;
00456 
00457         for (j = 0; j < SUBFR_SIZE; j++)
00458             fixed_vector[j] = excitation[j] - gain_code * fixed_vector[j];
00459 
00460         if (ctx->mode == MODE_5k0) {
00461             postfilter_5k0(ctx, pAz, fixed_vector);
00462 
00463             ff_celp_lp_synthesis_filterf(ctx->postfilter_syn5k0 + LP_FILTER_ORDER + i*SUBFR_SIZE,
00464                                          pAz, excitation, SUBFR_SIZE,
00465                                          LP_FILTER_ORDER);
00466         }
00467 
00468         ff_celp_lp_synthesis_filterf(synth + i*SUBFR_SIZE, pAz, fixed_vector,
00469                                      SUBFR_SIZE, LP_FILTER_ORDER);
00470 
00471         excitation += SUBFR_SIZE;
00472     }
00473 
00474     memcpy(synth - LP_FILTER_ORDER, synth + frame_size - LP_FILTER_ORDER,
00475            LP_FILTER_ORDER * sizeof(float));
00476 
00477     if (ctx->mode == MODE_5k0) {
00478         for (i = 0; i < subframe_count; i++) {
00479             float energy = ff_dot_productf(ctx->postfilter_syn5k0 + LP_FILTER_ORDER + i*SUBFR_SIZE,
00480                                            ctx->postfilter_syn5k0 + LP_FILTER_ORDER + i*SUBFR_SIZE,
00481                                            SUBFR_SIZE);
00482             ff_adaptive_gain_control(&synth[i * SUBFR_SIZE],
00483                                      &synth[i * SUBFR_SIZE], energy,
00484                                      SUBFR_SIZE, 0.9, &ctx->postfilter_agc);
00485         }
00486 
00487         memcpy(ctx->postfilter_syn5k0, ctx->postfilter_syn5k0 + frame_size,
00488                LP_FILTER_ORDER*sizeof(float));
00489     }
00490     memcpy(ctx->excitation, excitation - PITCH_DELAY_MAX - L_INTERPOL,
00491            (PITCH_DELAY_MAX + L_INTERPOL) * sizeof(float));
00492 
00493     ff_acelp_apply_order_2_transfer_function(out_data, synth,
00494                                              (const float[2]) {-1.99997   , 1.000000000},
00495                                              (const float[2]) {-1.93307352, 0.935891986},
00496                                              0.939805806,
00497                                              ctx->highpass_filt_mem,
00498                                              frame_size);
00499 }
00500 
00501 static av_cold int sipr_decoder_init(AVCodecContext * avctx)
00502 {
00503     SiprContext *ctx = avctx->priv_data;
00504     int i;
00505 
00506     if      (avctx->bit_rate > 12200) ctx->mode = MODE_16k;
00507     else if (avctx->bit_rate > 7500 ) ctx->mode = MODE_8k5;
00508     else if (avctx->bit_rate > 5750 ) ctx->mode = MODE_6k5;
00509     else                              ctx->mode = MODE_5k0;
00510 
00511     av_log(avctx, AV_LOG_DEBUG, "Mode: %s\n", modes[ctx->mode].mode_name);
00512 
00513     if (ctx->mode == MODE_16k)
00514         ff_sipr_init_16k(ctx);
00515 
00516     for (i = 0; i < LP_FILTER_ORDER; i++)
00517         ctx->lsp_history[i] = cos((i+1) * M_PI / (LP_FILTER_ORDER + 1));
00518 
00519     for (i = 0; i < 4; i++)
00520         ctx->energy_history[i] = -14;
00521 
00522     avctx->sample_fmt = SAMPLE_FMT_FLT;
00523 
00524     dsputil_init(&ctx->dsp, avctx);
00525 
00526     return 0;
00527 }
00528 
00529 static int sipr_decode_frame(AVCodecContext *avctx, void *datap,
00530                              int *data_size, AVPacket *avpkt)
00531 {
00532     SiprContext *ctx = avctx->priv_data;
00533     const uint8_t *buf=avpkt->data;
00534     SiprParameters parm;
00535     const SiprModeParam *mode_par = &modes[ctx->mode];
00536     GetBitContext gb;
00537     float *data = datap;
00538     int subframe_size = ctx->mode == MODE_16k ? L_SUBFR_16k : SUBFR_SIZE;
00539     int i;
00540 
00541     ctx->avctx = avctx;
00542     if (avpkt->size < (mode_par->bits_per_frame >> 3)) {
00543         av_log(avctx, AV_LOG_ERROR,
00544                "Error processing packet: packet size (%d) too small\n",
00545                avpkt->size);
00546 
00547         *data_size = 0;
00548         return -1;
00549     }
00550     if (*data_size < subframe_size * mode_par->subframe_count * sizeof(float)) {
00551         av_log(avctx, AV_LOG_ERROR,
00552                "Error processing packet: output buffer (%d) too small\n",
00553                *data_size);
00554 
00555         *data_size = 0;
00556         return -1;
00557     }
00558 
00559     init_get_bits(&gb, buf, mode_par->bits_per_frame);
00560 
00561     for (i = 0; i < mode_par->frames_per_packet; i++) {
00562         decode_parameters(&parm, &gb, mode_par);
00563 
00564         if (ctx->mode == MODE_16k)
00565             ff_sipr_decode_frame_16k(ctx, &parm, data);
00566         else
00567             decode_frame(ctx, &parm, data);
00568 
00569         data += subframe_size * mode_par->subframe_count;
00570     }
00571 
00572     *data_size = mode_par->frames_per_packet * subframe_size *
00573         mode_par->subframe_count * sizeof(float);
00574 
00575     return mode_par->bits_per_frame >> 3;
00576 };
00577 
00578 AVCodec sipr_decoder = {
00579     "sipr",
00580     AVMEDIA_TYPE_AUDIO,
00581     CODEC_ID_SIPR,
00582     sizeof(SiprContext),
00583     sipr_decoder_init,
00584     NULL,
00585     NULL,
00586     sipr_decode_frame,
00587     .long_name = NULL_IF_CONFIG_SMALL("RealAudio SIPR / ACELP.NET"),
00588 };

Generated on Fri Sep 16 2011 17:17:43 for FFmpeg by  doxygen 1.7.1