libavcodec/g723_1.c
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00001 /*
00002  * G.723.1 compatible decoder
00003  * Copyright (c) 2006 Benjamin Larsson
00004  * Copyright (c) 2010 Mohamed Naufal Basheer
00005  *
00006  * This file is part of FFmpeg.
00007  *
00008  * FFmpeg is free software; you can redistribute it and/or
00009  * modify it under the terms of the GNU Lesser General Public
00010  * License as published by the Free Software Foundation; either
00011  * version 2.1 of the License, or (at your option) any later version.
00012  *
00013  * FFmpeg is distributed in the hope that it will be useful,
00014  * but WITHOUT ANY WARRANTY; without even the implied warranty of
00015  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
00016  * Lesser General Public License for more details.
00017  *
00018  * You should have received a copy of the GNU Lesser General Public
00019  * License along with FFmpeg; if not, write to the Free Software
00020  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
00021  */
00022 
00028 #include "avcodec.h"
00029 #define BITSTREAM_READER_LE
00030 #include "get_bits.h"
00031 #include "acelp_vectors.h"
00032 #include "celp_filters.h"
00033 #include "celp_math.h"
00034 #include "lsp.h"
00035 #include "libavutil/lzo.h"
00036 #include "g723_1_data.h"
00037 
00038 typedef struct g723_1_context {
00039     AVFrame frame;
00040     G723_1_Subframe subframe[4];
00041     FrameType cur_frame_type;
00042     FrameType past_frame_type;
00043     Rate cur_rate;
00044     uint8_t lsp_index[LSP_BANDS];
00045     int pitch_lag[2];
00046     int erased_frames;
00047 
00048     int16_t prev_lsp[LPC_ORDER];
00049     int16_t prev_excitation[PITCH_MAX];
00050     int16_t excitation[PITCH_MAX + FRAME_LEN];
00051     int16_t synth_mem[LPC_ORDER];
00052     int16_t fir_mem[LPC_ORDER];
00053     int     iir_mem[LPC_ORDER];
00054 
00055     int random_seed;
00056     int interp_index;
00057     int interp_gain;
00058     int sid_gain;
00059     int cur_gain;
00060     int reflection_coef;
00061     int pf_gain;                 
00062 
00063 
00064     int16_t prev_data[HALF_FRAME_LEN];
00065     int16_t prev_weight_sig[PITCH_MAX];
00066 
00067 
00068     int16_t hpf_fir_mem;                   
00069     int     hpf_iir_mem;                   
00070     int16_t perf_fir_mem[LPC_ORDER];       
00071     int16_t perf_iir_mem[LPC_ORDER];       
00072 
00073     int16_t harmonic_mem[PITCH_MAX];
00074 } G723_1_Context;
00075 
00076 static av_cold int g723_1_decode_init(AVCodecContext *avctx)
00077 {
00078     G723_1_Context *p  = avctx->priv_data;
00079 
00080     avctx->sample_fmt  = AV_SAMPLE_FMT_S16;
00081     p->pf_gain         = 1 << 12;
00082     memcpy(p->prev_lsp, dc_lsp, LPC_ORDER * sizeof(int16_t));
00083 
00084     avcodec_get_frame_defaults(&p->frame);
00085     avctx->coded_frame = &p->frame;
00086 
00087     return 0;
00088 }
00089 
00097 static int unpack_bitstream(G723_1_Context *p, const uint8_t *buf,
00098                             int buf_size)
00099 {
00100     GetBitContext gb;
00101     int ad_cb_len;
00102     int temp, info_bits, i;
00103 
00104     init_get_bits(&gb, buf, buf_size * 8);
00105 
00106     /* Extract frame type and rate info */
00107     info_bits = get_bits(&gb, 2);
00108 
00109     if (info_bits == 3) {
00110         p->cur_frame_type = UntransmittedFrame;
00111         return 0;
00112     }
00113 
00114     /* Extract 24 bit lsp indices, 8 bit for each band */
00115     p->lsp_index[2] = get_bits(&gb, 8);
00116     p->lsp_index[1] = get_bits(&gb, 8);
00117     p->lsp_index[0] = get_bits(&gb, 8);
00118 
00119     if (info_bits == 2) {
00120         p->cur_frame_type = SIDFrame;
00121         p->subframe[0].amp_index = get_bits(&gb, 6);
00122         return 0;
00123     }
00124 
00125     /* Extract the info common to both rates */
00126     p->cur_rate       = info_bits ? Rate5k3 : Rate6k3;
00127     p->cur_frame_type = ActiveFrame;
00128 
00129     p->pitch_lag[0] = get_bits(&gb, 7);
00130     if (p->pitch_lag[0] > 123)       /* test if forbidden code */
00131         return -1;
00132     p->pitch_lag[0] += PITCH_MIN;
00133     p->subframe[1].ad_cb_lag = get_bits(&gb, 2);
00134 
00135     p->pitch_lag[1] = get_bits(&gb, 7);
00136     if (p->pitch_lag[1] > 123)
00137         return -1;
00138     p->pitch_lag[1] += PITCH_MIN;
00139     p->subframe[3].ad_cb_lag = get_bits(&gb, 2);
00140     p->subframe[0].ad_cb_lag = 1;
00141     p->subframe[2].ad_cb_lag = 1;
00142 
00143     for (i = 0; i < SUBFRAMES; i++) {
00144         /* Extract combined gain */
00145         temp = get_bits(&gb, 12);
00146         ad_cb_len = 170;
00147         p->subframe[i].dirac_train = 0;
00148         if (p->cur_rate == Rate6k3 && p->pitch_lag[i >> 1] < SUBFRAME_LEN - 2) {
00149             p->subframe[i].dirac_train = temp >> 11;
00150             temp &= 0x7ff;
00151             ad_cb_len = 85;
00152         }
00153         p->subframe[i].ad_cb_gain = FASTDIV(temp, GAIN_LEVELS);
00154         if (p->subframe[i].ad_cb_gain < ad_cb_len) {
00155             p->subframe[i].amp_index = temp - p->subframe[i].ad_cb_gain *
00156                                        GAIN_LEVELS;
00157         } else {
00158             return -1;
00159         }
00160     }
00161 
00162     p->subframe[0].grid_index = get_bits1(&gb);
00163     p->subframe[1].grid_index = get_bits1(&gb);
00164     p->subframe[2].grid_index = get_bits1(&gb);
00165     p->subframe[3].grid_index = get_bits1(&gb);
00166 
00167     if (p->cur_rate == Rate6k3) {
00168         skip_bits1(&gb);  /* skip reserved bit */
00169 
00170         /* Compute pulse_pos index using the 13-bit combined position index */
00171         temp = get_bits(&gb, 13);
00172         p->subframe[0].pulse_pos = temp / 810;
00173 
00174         temp -= p->subframe[0].pulse_pos * 810;
00175         p->subframe[1].pulse_pos = FASTDIV(temp, 90);
00176 
00177         temp -= p->subframe[1].pulse_pos * 90;
00178         p->subframe[2].pulse_pos = FASTDIV(temp, 9);
00179         p->subframe[3].pulse_pos = temp - p->subframe[2].pulse_pos * 9;
00180 
00181         p->subframe[0].pulse_pos = (p->subframe[0].pulse_pos << 16) +
00182                                    get_bits(&gb, 16);
00183         p->subframe[1].pulse_pos = (p->subframe[1].pulse_pos << 14) +
00184                                    get_bits(&gb, 14);
00185         p->subframe[2].pulse_pos = (p->subframe[2].pulse_pos << 16) +
00186                                    get_bits(&gb, 16);
00187         p->subframe[3].pulse_pos = (p->subframe[3].pulse_pos << 14) +
00188                                    get_bits(&gb, 14);
00189 
00190         p->subframe[0].pulse_sign = get_bits(&gb, 6);
00191         p->subframe[1].pulse_sign = get_bits(&gb, 5);
00192         p->subframe[2].pulse_sign = get_bits(&gb, 6);
00193         p->subframe[3].pulse_sign = get_bits(&gb, 5);
00194     } else { /* Rate5k3 */
00195         p->subframe[0].pulse_pos  = get_bits(&gb, 12);
00196         p->subframe[1].pulse_pos  = get_bits(&gb, 12);
00197         p->subframe[2].pulse_pos  = get_bits(&gb, 12);
00198         p->subframe[3].pulse_pos  = get_bits(&gb, 12);
00199 
00200         p->subframe[0].pulse_sign = get_bits(&gb, 4);
00201         p->subframe[1].pulse_sign = get_bits(&gb, 4);
00202         p->subframe[2].pulse_sign = get_bits(&gb, 4);
00203         p->subframe[3].pulse_sign = get_bits(&gb, 4);
00204     }
00205 
00206     return 0;
00207 }
00208 
00212 static int16_t square_root(int val)
00213 {
00214     return (ff_sqrt(val << 1) >> 1) & (~1);
00215 }
00216 
00223 static int normalize_bits(int num, int width)
00224 {
00225     int i = 0;
00226     int bits = (width) ? 31 : 15;
00227 
00228     if (num) {
00229         if (num == -1)
00230             return bits;
00231         if (num < 0)
00232             num = ~num;
00233         i= bits - av_log2(num) - 1;
00234         i= FFMAX(i, 0);
00235     }
00236     return i;
00237 }
00238 
00239 #define normalize_bits_int16(num) normalize_bits(num, 0)
00240 #define normalize_bits_int32(num) normalize_bits(num, 1)
00241 #define dot_product(a,b,c,d) (ff_dot_product(a,b,c)<<(d))
00242 
00246 static int scale_vector(int16_t *vector, int length)
00247 {
00248     int bits, scale, max = 0;
00249     int i;
00250 
00251     const int16_t shift_table[16] = {
00252         0x0001, 0x0002, 0x0004, 0x0008, 0x0010, 0x0020, 0x0040, 0x0080,
00253         0x0100, 0x0200, 0x0400, 0x0800, 0x1000, 0x2000, 0x4000, 0x7fff
00254     };
00255 
00256     for (i = 0; i < length; i++)
00257         max = FFMAX(max, FFABS(vector[i]));
00258 
00259     bits  = normalize_bits(max, 0);
00260     scale = shift_table[bits];
00261 
00262     for (i = 0; i < length; i++)
00263         vector[i] = (vector[i] * scale) >> 3;
00264 
00265     return bits - 3;
00266 }
00267 
00276 static void inverse_quant(int16_t *cur_lsp, int16_t *prev_lsp,
00277                           uint8_t *lsp_index, int bad_frame)
00278 {
00279     int min_dist, pred;
00280     int i, j, temp, stable;
00281 
00282     /* Check for frame erasure */
00283     if (!bad_frame) {
00284         min_dist     = 0x100;
00285         pred         = 12288;
00286     } else {
00287         min_dist     = 0x200;
00288         pred         = 23552;
00289         lsp_index[0] = lsp_index[1] = lsp_index[2] = 0;
00290     }
00291 
00292     /* Get the VQ table entry corresponding to the transmitted index */
00293     cur_lsp[0] = lsp_band0[lsp_index[0]][0];
00294     cur_lsp[1] = lsp_band0[lsp_index[0]][1];
00295     cur_lsp[2] = lsp_band0[lsp_index[0]][2];
00296     cur_lsp[3] = lsp_band1[lsp_index[1]][0];
00297     cur_lsp[4] = lsp_band1[lsp_index[1]][1];
00298     cur_lsp[5] = lsp_band1[lsp_index[1]][2];
00299     cur_lsp[6] = lsp_band2[lsp_index[2]][0];
00300     cur_lsp[7] = lsp_band2[lsp_index[2]][1];
00301     cur_lsp[8] = lsp_band2[lsp_index[2]][2];
00302     cur_lsp[9] = lsp_band2[lsp_index[2]][3];
00303 
00304     /* Add predicted vector & DC component to the previously quantized vector */
00305     for (i = 0; i < LPC_ORDER; i++) {
00306         temp        = ((prev_lsp[i] - dc_lsp[i]) * pred + (1 << 14)) >> 15;
00307         cur_lsp[i] += dc_lsp[i] + temp;
00308     }
00309 
00310     for (i = 0; i < LPC_ORDER; i++) {
00311         cur_lsp[0]             = FFMAX(cur_lsp[0],  0x180);
00312         cur_lsp[LPC_ORDER - 1] = FFMIN(cur_lsp[LPC_ORDER - 1], 0x7e00);
00313 
00314         /* Stability check */
00315         for (j = 1; j < LPC_ORDER; j++) {
00316             temp = min_dist + cur_lsp[j - 1] - cur_lsp[j];
00317             if (temp > 0) {
00318                 temp >>= 1;
00319                 cur_lsp[j - 1] -= temp;
00320                 cur_lsp[j]     += temp;
00321             }
00322         }
00323         stable = 1;
00324         for (j = 1; j < LPC_ORDER; j++) {
00325             temp = cur_lsp[j - 1] + min_dist - cur_lsp[j] - 4;
00326             if (temp > 0) {
00327                 stable = 0;
00328                 break;
00329             }
00330         }
00331         if (stable)
00332             break;
00333     }
00334     if (!stable)
00335         memcpy(cur_lsp, prev_lsp, LPC_ORDER * sizeof(int16_t));
00336 }
00337 
00344 #define MULL2(a, b) \
00345         MULL(a,b,15)
00346 
00352 static void lsp2lpc(int16_t *lpc)
00353 {
00354     int f1[LPC_ORDER / 2 + 1];
00355     int f2[LPC_ORDER / 2 + 1];
00356     int i, j;
00357 
00358     /* Calculate negative cosine */
00359     for (j = 0; j < LPC_ORDER; j++) {
00360         int index     = lpc[j] >> 7;
00361         int offset    = lpc[j] & 0x7f;
00362         int64_t temp1 = cos_tab[index] << 16;
00363         int temp2     = (cos_tab[index + 1] - cos_tab[index]) *
00364                           ((offset << 8) + 0x80) << 1;
00365 
00366         lpc[j] = -(av_clipl_int32(((temp1 + temp2) << 1) + (1 << 15)) >> 16);
00367     }
00368 
00369     /*
00370      * Compute sum and difference polynomial coefficients
00371      * (bitexact alternative to lsp2poly() in lsp.c)
00372      */
00373     /* Initialize with values in Q28 */
00374     f1[0] = 1 << 28;
00375     f1[1] = (lpc[0] << 14) + (lpc[2] << 14);
00376     f1[2] = lpc[0] * lpc[2] + (2 << 28);
00377 
00378     f2[0] = 1 << 28;
00379     f2[1] = (lpc[1] << 14) + (lpc[3] << 14);
00380     f2[2] = lpc[1] * lpc[3] + (2 << 28);
00381 
00382     /*
00383      * Calculate and scale the coefficients by 1/2 in
00384      * each iteration for a final scaling factor of Q25
00385      */
00386     for (i = 2; i < LPC_ORDER / 2; i++) {
00387         f1[i + 1] = f1[i - 1] + MULL2(f1[i], lpc[2 * i]);
00388         f2[i + 1] = f2[i - 1] + MULL2(f2[i], lpc[2 * i + 1]);
00389 
00390         for (j = i; j >= 2; j--) {
00391             f1[j] = MULL2(f1[j - 1], lpc[2 * i]) +
00392                     (f1[j] >> 1) + (f1[j - 2] >> 1);
00393             f2[j] = MULL2(f2[j - 1], lpc[2 * i + 1]) +
00394                     (f2[j] >> 1) + (f2[j - 2] >> 1);
00395         }
00396 
00397         f1[0] >>= 1;
00398         f2[0] >>= 1;
00399         f1[1] = ((lpc[2 * i]     << 16 >> i) + f1[1]) >> 1;
00400         f2[1] = ((lpc[2 * i + 1] << 16 >> i) + f2[1]) >> 1;
00401     }
00402 
00403     /* Convert polynomial coefficients to LPC coefficients */
00404     for (i = 0; i < LPC_ORDER / 2; i++) {
00405         int64_t ff1 = f1[i + 1] + f1[i];
00406         int64_t ff2 = f2[i + 1] - f2[i];
00407 
00408         lpc[i] = av_clipl_int32(((ff1 + ff2) << 3) + (1 << 15)) >> 16;
00409         lpc[LPC_ORDER - i - 1] = av_clipl_int32(((ff1 - ff2) << 3) +
00410                                                 (1 << 15)) >> 16;
00411     }
00412 }
00413 
00422 static void lsp_interpolate(int16_t *lpc, int16_t *cur_lsp, int16_t *prev_lsp)
00423 {
00424     int i;
00425     int16_t *lpc_ptr = lpc;
00426 
00427     /* cur_lsp * 0.25 + prev_lsp * 0.75 */
00428     ff_acelp_weighted_vector_sum(lpc, cur_lsp, prev_lsp,
00429                                  4096, 12288, 1 << 13, 14, LPC_ORDER);
00430     ff_acelp_weighted_vector_sum(lpc + LPC_ORDER, cur_lsp, prev_lsp,
00431                                  8192, 8192, 1 << 13, 14, LPC_ORDER);
00432     ff_acelp_weighted_vector_sum(lpc + 2 * LPC_ORDER, cur_lsp, prev_lsp,
00433                                  12288, 4096, 1 << 13, 14, LPC_ORDER);
00434     memcpy(lpc + 3 * LPC_ORDER, cur_lsp, LPC_ORDER * sizeof(int16_t));
00435 
00436     for (i = 0; i < SUBFRAMES; i++) {
00437         lsp2lpc(lpc_ptr);
00438         lpc_ptr += LPC_ORDER;
00439     }
00440 }
00441 
00445 static void gen_dirac_train(int16_t *buf, int pitch_lag)
00446 {
00447     int16_t vector[SUBFRAME_LEN];
00448     int i, j;
00449 
00450     memcpy(vector, buf, SUBFRAME_LEN * sizeof(int16_t));
00451     for (i = pitch_lag; i < SUBFRAME_LEN; i += pitch_lag) {
00452         for (j = 0; j < SUBFRAME_LEN - i; j++)
00453             buf[i + j] += vector[j];
00454     }
00455 }
00456 
00466 static void gen_fcb_excitation(int16_t *vector, G723_1_Subframe subfrm,
00467                                Rate cur_rate, int pitch_lag, int index)
00468 {
00469     int temp, i, j;
00470 
00471     memset(vector, 0, SUBFRAME_LEN * sizeof(int16_t));
00472 
00473     if (cur_rate == Rate6k3) {
00474         if (subfrm.pulse_pos >= max_pos[index])
00475             return;
00476 
00477         /* Decode amplitudes and positions */
00478         j = PULSE_MAX - pulses[index];
00479         temp = subfrm.pulse_pos;
00480         for (i = 0; i < SUBFRAME_LEN / GRID_SIZE; i++) {
00481             temp -= combinatorial_table[j][i];
00482             if (temp >= 0)
00483                 continue;
00484             temp += combinatorial_table[j++][i];
00485             if (subfrm.pulse_sign & (1 << (PULSE_MAX - j))) {
00486                 vector[subfrm.grid_index + GRID_SIZE * i] =
00487                                         -fixed_cb_gain[subfrm.amp_index];
00488             } else {
00489                 vector[subfrm.grid_index + GRID_SIZE * i] =
00490                                          fixed_cb_gain[subfrm.amp_index];
00491             }
00492             if (j == PULSE_MAX)
00493                 break;
00494         }
00495         if (subfrm.dirac_train == 1)
00496             gen_dirac_train(vector, pitch_lag);
00497     } else { /* Rate5k3 */
00498         int cb_gain  = fixed_cb_gain[subfrm.amp_index];
00499         int cb_shift = subfrm.grid_index;
00500         int cb_sign  = subfrm.pulse_sign;
00501         int cb_pos   = subfrm.pulse_pos;
00502         int offset, beta, lag;
00503 
00504         for (i = 0; i < 8; i += 2) {
00505             offset         = ((cb_pos & 7) << 3) + cb_shift + i;
00506             vector[offset] = (cb_sign & 1) ? cb_gain : -cb_gain;
00507             cb_pos  >>= 3;
00508             cb_sign >>= 1;
00509         }
00510 
00511         /* Enhance harmonic components */
00512         lag  = pitch_contrib[subfrm.ad_cb_gain << 1] + pitch_lag +
00513                subfrm.ad_cb_lag - 1;
00514         beta = pitch_contrib[(subfrm.ad_cb_gain << 1) + 1];
00515 
00516         if (lag < SUBFRAME_LEN - 2) {
00517             for (i = lag; i < SUBFRAME_LEN; i++)
00518                 vector[i] += beta * vector[i - lag] >> 15;
00519         }
00520     }
00521 }
00522 
00526 static void get_residual(int16_t *residual, int16_t *prev_excitation, int lag)
00527 {
00528     int offset = PITCH_MAX - PITCH_ORDER / 2 - lag;
00529     int i;
00530 
00531     residual[0] = prev_excitation[offset];
00532     residual[1] = prev_excitation[offset + 1];
00533 
00534     offset += 2;
00535     for (i = 2; i < SUBFRAME_LEN + PITCH_ORDER - 1; i++)
00536         residual[i] = prev_excitation[offset + (i - 2) % lag];
00537 }
00538 
00542 static void gen_acb_excitation(int16_t *vector, int16_t *prev_excitation,
00543                                int pitch_lag, G723_1_Subframe subfrm,
00544                                Rate cur_rate)
00545 {
00546     int16_t residual[SUBFRAME_LEN + PITCH_ORDER - 1];
00547     const int16_t *cb_ptr;
00548     int lag = pitch_lag + subfrm.ad_cb_lag - 1;
00549 
00550     int i;
00551     int64_t sum;
00552 
00553     get_residual(residual, prev_excitation, lag);
00554 
00555     /* Select quantization table */
00556     if (cur_rate == Rate6k3 && pitch_lag < SUBFRAME_LEN - 2) {
00557         cb_ptr = adaptive_cb_gain85;
00558     } else
00559         cb_ptr = adaptive_cb_gain170;
00560 
00561     /* Calculate adaptive vector */
00562     cb_ptr += subfrm.ad_cb_gain * 20;
00563     for (i = 0; i < SUBFRAME_LEN; i++) {
00564         sum = ff_dot_product(residual + i, cb_ptr, PITCH_ORDER);
00565         vector[i] = av_clipl_int32((sum << 2) + (1 << 15)) >> 16;
00566     }
00567 }
00568 
00579 static int autocorr_max(G723_1_Context *p, int offset, int *ccr_max,
00580                         int pitch_lag, int length, int dir)
00581 {
00582     int limit, ccr, lag = 0;
00583     int16_t *buf = p->excitation + offset;
00584     int i;
00585 
00586     pitch_lag = FFMIN(PITCH_MAX - 3, pitch_lag);
00587     limit     = FFMIN(FRAME_LEN + PITCH_MAX - offset - length, pitch_lag + 3);
00588 
00589     for (i = pitch_lag - 3; i <= limit; i++) {
00590         ccr = ff_dot_product(buf, buf + dir * i, length)<<1;
00591 
00592         if (ccr > *ccr_max) {
00593             *ccr_max = ccr;
00594             lag = i;
00595         }
00596     }
00597     return lag;
00598 }
00599 
00610 static void comp_ppf_gains(int lag, PPFParam *ppf, Rate cur_rate,
00611                            int tgt_eng, int ccr, int res_eng)
00612 {
00613     int pf_residual;     /* square of postfiltered residual */
00614     int64_t temp1, temp2;
00615 
00616     ppf->index = lag;
00617 
00618     temp1 = tgt_eng * res_eng >> 1;
00619     temp2 = ccr * ccr << 1;
00620 
00621     if (temp2 > temp1) {
00622         if (ccr >= res_eng) {
00623             ppf->opt_gain = ppf_gain_weight[cur_rate];
00624         } else {
00625             ppf->opt_gain = (ccr << 15) / res_eng *
00626                             ppf_gain_weight[cur_rate] >> 15;
00627         }
00628         /* pf_res^2 = tgt_eng + 2*ccr*gain + res_eng*gain^2 */
00629         temp1       = (tgt_eng << 15) + (ccr * ppf->opt_gain << 1);
00630         temp2       = (ppf->opt_gain * ppf->opt_gain >> 15) * res_eng;
00631         pf_residual = av_clipl_int32(temp1 + temp2 + (1 << 15)) >> 16;
00632 
00633         if (tgt_eng >= pf_residual << 1) {
00634             temp1 = 0x7fff;
00635         } else {
00636             temp1 = (tgt_eng << 14) / pf_residual;
00637         }
00638 
00639         /* scaling_gain = sqrt(tgt_eng/pf_res^2) */
00640         ppf->sc_gain = square_root(temp1 << 16);
00641     } else {
00642         ppf->opt_gain = 0;
00643         ppf->sc_gain  = 0x7fff;
00644     }
00645 
00646     ppf->opt_gain = av_clip_int16(ppf->opt_gain * ppf->sc_gain >> 15);
00647 }
00648 
00658 static void comp_ppf_coeff(G723_1_Context *p, int offset, int pitch_lag,
00659                            PPFParam *ppf, Rate cur_rate)
00660 {
00661 
00662     int16_t scale;
00663     int i;
00664     int64_t temp1, temp2;
00665 
00666     /*
00667      * 0 - target energy
00668      * 1 - forward cross-correlation
00669      * 2 - forward residual energy
00670      * 3 - backward cross-correlation
00671      * 4 - backward residual energy
00672      */
00673     int energy[5] = {0, 0, 0, 0, 0};
00674     int16_t *buf  = p->excitation + offset;
00675     int fwd_lag   = autocorr_max(p, offset, &energy[1], pitch_lag,
00676                                  SUBFRAME_LEN, 1);
00677     int back_lag  = autocorr_max(p, offset, &energy[3], pitch_lag,
00678                                  SUBFRAME_LEN, -1);
00679 
00680     ppf->index    = 0;
00681     ppf->opt_gain = 0;
00682     ppf->sc_gain  = 0x7fff;
00683 
00684     /* Case 0, Section 3.6 */
00685     if (!back_lag && !fwd_lag)
00686         return;
00687 
00688     /* Compute target energy */
00689     energy[0] = ff_dot_product(buf, buf, SUBFRAME_LEN)<<1;
00690 
00691     /* Compute forward residual energy */
00692     if (fwd_lag)
00693         energy[2] = ff_dot_product(buf + fwd_lag, buf + fwd_lag,
00694                                    SUBFRAME_LEN)<<1;
00695 
00696     /* Compute backward residual energy */
00697     if (back_lag)
00698         energy[4] = ff_dot_product(buf - back_lag, buf - back_lag,
00699                                    SUBFRAME_LEN)<<1;
00700 
00701     /* Normalize and shorten */
00702     temp1 = 0;
00703     for (i = 0; i < 5; i++)
00704         temp1 = FFMAX(energy[i], temp1);
00705 
00706     scale = normalize_bits(temp1, 1);
00707     for (i = 0; i < 5; i++)
00708         energy[i] = av_clipl_int32(energy[i] << scale) >> 16;
00709 
00710     if (fwd_lag && !back_lag) {  /* Case 1 */
00711         comp_ppf_gains(fwd_lag,  ppf, cur_rate, energy[0], energy[1],
00712                        energy[2]);
00713     } else if (!fwd_lag) {       /* Case 2 */
00714         comp_ppf_gains(-back_lag, ppf, cur_rate, energy[0], energy[3],
00715                        energy[4]);
00716     } else {                     /* Case 3 */
00717 
00718         /*
00719          * Select the largest of energy[1]^2/energy[2]
00720          * and energy[3]^2/energy[4]
00721          */
00722         temp1 = energy[4] * ((energy[1] * energy[1] + (1 << 14)) >> 15);
00723         temp2 = energy[2] * ((energy[3] * energy[3] + (1 << 14)) >> 15);
00724         if (temp1 >= temp2) {
00725             comp_ppf_gains(fwd_lag, ppf, cur_rate, energy[0], energy[1],
00726                            energy[2]);
00727         } else {
00728             comp_ppf_gains(-back_lag, ppf, cur_rate, energy[0], energy[3],
00729                            energy[4]);
00730         }
00731     }
00732 }
00733 
00744 static int comp_interp_index(G723_1_Context *p, int pitch_lag,
00745                              int *exc_eng, int *scale)
00746 {
00747     int offset = PITCH_MAX + 2 * SUBFRAME_LEN;
00748     int16_t *buf = p->excitation + offset;
00749 
00750     int index, ccr, tgt_eng, best_eng, temp;
00751 
00752     *scale = scale_vector(p->excitation, FRAME_LEN + PITCH_MAX);
00753 
00754     /* Compute maximum backward cross-correlation */
00755     ccr   = 0;
00756     index = autocorr_max(p, offset, &ccr, pitch_lag, SUBFRAME_LEN * 2, -1);
00757     ccr   = av_clipl_int32((int64_t)ccr + (1 << 15)) >> 16;
00758 
00759     /* Compute target energy */
00760     tgt_eng  = ff_dot_product(buf, buf, SUBFRAME_LEN * 2)<<1;
00761     *exc_eng = av_clipl_int32(tgt_eng + (1 << 15)) >> 16;
00762 
00763     if (ccr <= 0)
00764         return 0;
00765 
00766     /* Compute best energy */
00767     best_eng = ff_dot_product(buf - index, buf - index,
00768                               SUBFRAME_LEN * 2)<<1;
00769     best_eng = av_clipl_int32((int64_t)best_eng + (1 << 15)) >> 16;
00770 
00771     temp = best_eng * *exc_eng >> 3;
00772 
00773     if (temp < ccr * ccr) {
00774         return index;
00775     } else
00776         return 0;
00777 }
00778 
00788 static void residual_interp(int16_t *buf, int16_t *out, int lag,
00789                             int gain, int *rseed)
00790 {
00791     int i;
00792     if (lag) { /* Voiced */
00793         int16_t *vector_ptr = buf + PITCH_MAX;
00794         /* Attenuate */
00795         for (i = 0; i < lag; i++)
00796             vector_ptr[i - lag] = vector_ptr[i - lag] * 3 >> 2;
00797         av_memcpy_backptr((uint8_t*)vector_ptr, lag * sizeof(int16_t),
00798                           FRAME_LEN * sizeof(int16_t));
00799         memcpy(out, vector_ptr, FRAME_LEN * sizeof(int16_t));
00800     } else {  /* Unvoiced */
00801         for (i = 0; i < FRAME_LEN; i++) {
00802             *rseed = *rseed * 521 + 259;
00803             out[i] = gain * *rseed >> 15;
00804         }
00805         memset(buf, 0, (FRAME_LEN + PITCH_MAX) * sizeof(int16_t));
00806     }
00807 }
00808 
00818 #define iir_filter(fir_coef, iir_coef, src, dest, width)\
00819 {\
00820     int m, n;\
00821     int res_shift = 16 & ~-(width);\
00822     int in_shift  = 16 - res_shift;\
00823 \
00824     for (m = 0; m < SUBFRAME_LEN; m++) {\
00825         int64_t filter = 0;\
00826         for (n = 1; n <= LPC_ORDER; n++) {\
00827             filter -= (fir_coef)[n - 1] * (src)[m - n] -\
00828                       (iir_coef)[n - 1] * ((dest)[m - n] >> in_shift);\
00829         }\
00830 \
00831         (dest)[m] = av_clipl_int32(((src)[m] << 16) + (filter << 3) +\
00832                                    (1 << 15)) >> res_shift;\
00833     }\
00834 }
00835 
00843 static void gain_scale(G723_1_Context *p, int16_t * buf, int energy)
00844 {
00845     int num, denom, gain, bits1, bits2;
00846     int i;
00847 
00848     num   = energy;
00849     denom = 0;
00850     for (i = 0; i < SUBFRAME_LEN; i++) {
00851         int64_t temp = buf[i] >> 2;
00852         temp  = av_clipl_int32(MUL64(temp, temp) << 1);
00853         denom = av_clipl_int32(denom + temp);
00854     }
00855 
00856     if (num && denom) {
00857         bits1   = normalize_bits(num, 1);
00858         bits2   = normalize_bits(denom, 1);
00859         num     = num << bits1 >> 1;
00860         denom <<= bits2;
00861 
00862         bits2 = 5 + bits1 - bits2;
00863         bits2 = FFMAX(0, bits2);
00864 
00865         gain = (num >> 1) / (denom >> 16);
00866         gain = square_root(gain << 16 >> bits2);
00867     } else {
00868         gain = 1 << 12;
00869     }
00870 
00871     for (i = 0; i < SUBFRAME_LEN; i++) {
00872         p->pf_gain = ((p->pf_gain << 4) - p->pf_gain + gain + (1 << 3)) >> 4;
00873         buf[i]     = av_clip_int16((buf[i] * (p->pf_gain + (p->pf_gain >> 4)) +
00874                                    (1 << 10)) >> 11);
00875     }
00876 }
00877 
00885 static void formant_postfilter(G723_1_Context *p, int16_t *lpc, int16_t *buf)
00886 {
00887     int16_t filter_coef[2][LPC_ORDER], *buf_ptr;
00888     int filter_signal[LPC_ORDER + FRAME_LEN], *signal_ptr;
00889     int i, j, k;
00890 
00891     memcpy(buf, p->fir_mem, LPC_ORDER * sizeof(int16_t));
00892     memcpy(filter_signal, p->iir_mem, LPC_ORDER * sizeof(int));
00893 
00894     for (i = LPC_ORDER, j = 0; j < SUBFRAMES; i += SUBFRAME_LEN, j++) {
00895         for (k = 0; k < LPC_ORDER; k++) {
00896             filter_coef[0][k] = (-lpc[k] * postfilter_tbl[0][k] +
00897                                  (1 << 14)) >> 15;
00898             filter_coef[1][k] = (-lpc[k] * postfilter_tbl[1][k] +
00899                                  (1 << 14)) >> 15;
00900         }
00901         iir_filter(filter_coef[0], filter_coef[1], buf + i,
00902                    filter_signal + i, 1);
00903     }
00904 
00905     memcpy(p->fir_mem, buf + FRAME_LEN, LPC_ORDER * sizeof(int16_t));
00906     memcpy(p->iir_mem, filter_signal + FRAME_LEN, LPC_ORDER * sizeof(int));
00907 
00908     buf_ptr    = buf + LPC_ORDER;
00909     signal_ptr = filter_signal + LPC_ORDER;
00910     for (i = 0; i < SUBFRAMES; i++) {
00911         int16_t temp_vector[SUBFRAME_LEN];
00912         int16_t temp;
00913         int auto_corr[2];
00914         int scale, energy;
00915 
00916         /* Normalize */
00917         memcpy(temp_vector, buf_ptr, SUBFRAME_LEN * sizeof(int16_t));
00918         scale = scale_vector(temp_vector, SUBFRAME_LEN);
00919 
00920         /* Compute auto correlation coefficients */
00921         auto_corr[0] = ff_dot_product(temp_vector, temp_vector + 1,
00922                                       SUBFRAME_LEN - 1)<<1;
00923         auto_corr[1] = ff_dot_product(temp_vector, temp_vector,
00924                                       SUBFRAME_LEN)<<1;
00925 
00926         /* Compute reflection coefficient */
00927         temp = auto_corr[1] >> 16;
00928         if (temp) {
00929             temp = (auto_corr[0] >> 2) / temp;
00930         }
00931         p->reflection_coef = ((p->reflection_coef << 2) - p->reflection_coef +
00932                               temp + 2) >> 2;
00933         temp = (p->reflection_coef * 0xffffc >> 3) & 0xfffc;
00934 
00935         /* Compensation filter */
00936         for (j = 0; j < SUBFRAME_LEN; j++) {
00937             buf_ptr[j] = av_clipl_int32(signal_ptr[j] +
00938                                         ((signal_ptr[j - 1] >> 16) *
00939                                          temp << 1)) >> 16;
00940         }
00941 
00942         /* Compute normalized signal energy */
00943         temp = 2 * scale + 4;
00944         if (temp < 0) {
00945             energy = av_clipl_int32((int64_t)auto_corr[1] << -temp);
00946         } else
00947             energy = auto_corr[1] >> temp;
00948 
00949         gain_scale(p, buf_ptr, energy);
00950 
00951         buf_ptr    += SUBFRAME_LEN;
00952         signal_ptr += SUBFRAME_LEN;
00953     }
00954 }
00955 
00956 static int g723_1_decode_frame(AVCodecContext *avctx, void *data,
00957                                int *got_frame_ptr, AVPacket *avpkt)
00958 {
00959     G723_1_Context *p  = avctx->priv_data;
00960     const uint8_t *buf = avpkt->data;
00961     int buf_size       = avpkt->size;
00962     int16_t *out;
00963     int dec_mode       = buf[0] & 3;
00964 
00965     PPFParam ppf[SUBFRAMES];
00966     int16_t cur_lsp[LPC_ORDER];
00967     int16_t lpc[SUBFRAMES * LPC_ORDER];
00968     int16_t acb_vector[SUBFRAME_LEN];
00969     int16_t *vector_ptr;
00970     int bad_frame = 0, i, j, ret;
00971 
00972     if (!buf_size || buf_size < frame_size[dec_mode]) {
00973         *got_frame_ptr = 0;
00974         return buf_size;
00975     }
00976 
00977     if (unpack_bitstream(p, buf, buf_size) < 0) {
00978         bad_frame         = 1;
00979         p->cur_frame_type = p->past_frame_type == ActiveFrame ?
00980                             ActiveFrame : UntransmittedFrame;
00981     }
00982 
00983     p->frame.nb_samples = FRAME_LEN + LPC_ORDER;
00984     if ((ret = avctx->get_buffer(avctx, &p->frame)) < 0) {
00985         av_log(avctx, AV_LOG_ERROR, "get_buffer() failed\n");
00986         return ret;
00987     }
00988     out= (int16_t*)p->frame.data[0];
00989 
00990 
00991     if(p->cur_frame_type == ActiveFrame) {
00992         if (!bad_frame) {
00993             p->erased_frames = 0;
00994         } else if(p->erased_frames != 3)
00995             p->erased_frames++;
00996 
00997         inverse_quant(cur_lsp, p->prev_lsp, p->lsp_index, bad_frame);
00998         lsp_interpolate(lpc, cur_lsp, p->prev_lsp);
00999 
01000         /* Save the lsp_vector for the next frame */
01001         memcpy(p->prev_lsp, cur_lsp, LPC_ORDER * sizeof(int16_t));
01002 
01003         /* Generate the excitation for the frame */
01004         memcpy(p->excitation, p->prev_excitation, PITCH_MAX * sizeof(int16_t));
01005         vector_ptr = p->excitation + PITCH_MAX;
01006         if (!p->erased_frames) {
01007             /* Update interpolation gain memory */
01008             p->interp_gain = fixed_cb_gain[(p->subframe[2].amp_index +
01009                                             p->subframe[3].amp_index) >> 1];
01010             for (i = 0; i < SUBFRAMES; i++) {
01011                 gen_fcb_excitation(vector_ptr, p->subframe[i], p->cur_rate,
01012                                    p->pitch_lag[i >> 1], i);
01013                 gen_acb_excitation(acb_vector, &p->excitation[SUBFRAME_LEN * i],
01014                                    p->pitch_lag[i >> 1], p->subframe[i],
01015                                    p->cur_rate);
01016                 /* Get the total excitation */
01017                 for (j = 0; j < SUBFRAME_LEN; j++) {
01018                     vector_ptr[j] = av_clip_int16(vector_ptr[j] << 1);
01019                     vector_ptr[j] = av_clip_int16(vector_ptr[j] +
01020                                                   acb_vector[j]);
01021                 }
01022                 vector_ptr += SUBFRAME_LEN;
01023             }
01024 
01025             vector_ptr = p->excitation + PITCH_MAX;
01026 
01027             /* Save the excitation */
01028             memcpy(out, vector_ptr, FRAME_LEN * sizeof(int16_t));
01029 
01030             p->interp_index = comp_interp_index(p, p->pitch_lag[1],
01031                                                 &p->sid_gain, &p->cur_gain);
01032 
01033             for (i = PITCH_MAX, j = 0; j < SUBFRAMES; i += SUBFRAME_LEN, j++)
01034                 comp_ppf_coeff(p, i, p->pitch_lag[j >> 1],
01035                                ppf + j, p->cur_rate);
01036 
01037             /* Restore the original excitation */
01038             memcpy(p->excitation, p->prev_excitation,
01039                    PITCH_MAX * sizeof(int16_t));
01040             memcpy(vector_ptr, out, FRAME_LEN * sizeof(int16_t));
01041 
01042             /* Peform pitch postfiltering */
01043             for (i = 0, j = 0; j < SUBFRAMES; i += SUBFRAME_LEN, j++)
01044                 ff_acelp_weighted_vector_sum(out + LPC_ORDER + i, vector_ptr + i,
01045                                              vector_ptr + i + ppf[j].index,
01046                                              ppf[j].sc_gain, ppf[j].opt_gain,
01047                                              1 << 14, 15, SUBFRAME_LEN);
01048         } else {
01049             p->interp_gain = (p->interp_gain * 3 + 2) >> 2;
01050             if (p->erased_frames == 3) {
01051                 /* Mute output */
01052                 memset(p->excitation, 0,
01053                        (FRAME_LEN + PITCH_MAX) * sizeof(int16_t));
01054                 memset(out, 0, (FRAME_LEN + LPC_ORDER) * sizeof(int16_t));
01055             } else {
01056                 /* Regenerate frame */
01057                 residual_interp(p->excitation, out + LPC_ORDER, p->interp_index,
01058                                 p->interp_gain, &p->random_seed);
01059             }
01060         }
01061         /* Save the excitation for the next frame */
01062         memcpy(p->prev_excitation, p->excitation + FRAME_LEN,
01063                PITCH_MAX * sizeof(int16_t));
01064     } else {
01065         memset(out, 0, sizeof(int16_t)*FRAME_LEN);
01066         av_log(avctx, AV_LOG_WARNING,
01067                "G.723.1: Comfort noise generation not supported yet\n");
01068         return frame_size[dec_mode];
01069     }
01070 
01071     p->past_frame_type = p->cur_frame_type;
01072 
01073     memcpy(out, p->synth_mem, LPC_ORDER * sizeof(int16_t));
01074     for (i = LPC_ORDER, j = 0; j < SUBFRAMES; i += SUBFRAME_LEN, j++)
01075         ff_celp_lp_synthesis_filter(out + i, &lpc[j * LPC_ORDER],
01076                                     out + i, SUBFRAME_LEN, LPC_ORDER,
01077                                     0, 1, 1 << 12);
01078     memcpy(p->synth_mem, out + FRAME_LEN, LPC_ORDER * sizeof(int16_t));
01079 
01080     formant_postfilter(p, lpc, out);
01081 
01082     memmove(out, out + LPC_ORDER, sizeof(int16_t)*FRAME_LEN);
01083     p->frame.nb_samples = FRAME_LEN;
01084     *(AVFrame*)data = p->frame;
01085     *got_frame_ptr = 1;
01086 
01087     return frame_size[dec_mode];
01088 }
01089 
01090 AVCodec ff_g723_1_decoder = {
01091     .name           = "g723_1",
01092     .type           = AVMEDIA_TYPE_AUDIO,
01093     .id             = CODEC_ID_G723_1,
01094     .priv_data_size = sizeof(G723_1_Context),
01095     .init           = g723_1_decode_init,
01096     .decode         = g723_1_decode_frame,
01097     .long_name      = NULL_IF_CONFIG_SMALL("G.723.1"),
01098     .capabilities   = CODEC_CAP_SUBFRAMES,
01099 };
01100 
01101 #if CONFIG_G723_1_ENCODER
01102 #define BITSTREAM_WRITER_LE
01103 #include "put_bits.h"
01104 
01105 static av_cold int g723_1_encode_init(AVCodecContext *avctx)
01106 {
01107     G723_1_Context *p = avctx->priv_data;
01108 
01109     if (avctx->sample_rate != 8000) {
01110         av_log(avctx, AV_LOG_ERROR, "Only 8000Hz sample rate supported\n");
01111         return -1;
01112     }
01113 
01114     if (avctx->channels != 1) {
01115         av_log(avctx, AV_LOG_ERROR, "Only mono supported\n");
01116         return AVERROR(EINVAL);
01117     }
01118 
01119     if (avctx->bit_rate == 6300) {
01120         p->cur_rate = Rate6k3;
01121     } else if (avctx->bit_rate == 5300) {
01122         av_log(avctx, AV_LOG_ERROR, "Bitrate not supported yet, use 6.3k\n");
01123         return AVERROR_PATCHWELCOME;
01124     } else {
01125         av_log(avctx, AV_LOG_ERROR,
01126                "Bitrate not supported, use 6.3k\n");
01127         return AVERROR(EINVAL);
01128     }
01129     avctx->frame_size = 240;
01130     memcpy(p->prev_lsp, dc_lsp, LPC_ORDER * sizeof(int16_t));
01131 
01132     return 0;
01133 }
01134 
01142 static void highpass_filter(int16_t *buf, int16_t *fir, int *iir)
01143 {
01144     int i;
01145     for (i = 0; i < FRAME_LEN; i++) {
01146         *iir   = (buf[i] << 15) + ((-*fir) << 15) + MULL2(*iir, 0x7f00);
01147         *fir   = buf[i];
01148         buf[i] = av_clipl_int32((int64_t)*iir + (1 << 15)) >> 16;
01149     }
01150 }
01151 
01158 static void comp_autocorr(int16_t *buf, int16_t *autocorr)
01159 {
01160     int i, scale, temp;
01161     int16_t vector[LPC_FRAME];
01162 
01163     memcpy(vector, buf, LPC_FRAME * sizeof(int16_t));
01164     scale_vector(vector, LPC_FRAME);
01165 
01166     /* Apply the Hamming window */
01167     for (i = 0; i < LPC_FRAME; i++)
01168         vector[i] = (vector[i] * hamming_window[i] + (1 << 14)) >> 15;
01169 
01170     /* Compute the first autocorrelation coefficient */
01171     temp = dot_product(vector, vector, LPC_FRAME, 0);
01172 
01173     /* Apply a white noise correlation factor of (1025/1024) */
01174     temp += temp >> 10;
01175 
01176     /* Normalize */
01177     scale = normalize_bits_int32(temp);
01178     autocorr[0] = av_clipl_int32((int64_t)(temp << scale) +
01179                                  (1 << 15)) >> 16;
01180 
01181     /* Compute the remaining coefficients */
01182     if (!autocorr[0]) {
01183         memset(autocorr + 1, 0, LPC_ORDER * sizeof(int16_t));
01184     } else {
01185         for (i = 1; i <= LPC_ORDER; i++) {
01186            temp = dot_product(vector, vector + i, LPC_FRAME - i, 0);
01187            temp = MULL2((temp << scale), binomial_window[i - 1]);
01188            autocorr[i] = av_clipl_int32((int64_t)temp + (1 << 15)) >> 16;
01189         }
01190     }
01191 }
01192 
01201 static void levinson_durbin(int16_t *lpc, int16_t *autocorr, int16_t error)
01202 {
01203     int16_t vector[LPC_ORDER];
01204     int16_t partial_corr;
01205     int i, j, temp;
01206 
01207     memset(lpc, 0, LPC_ORDER * sizeof(int16_t));
01208 
01209     for (i = 0; i < LPC_ORDER; i++) {
01210         /* Compute the partial correlation coefficient */
01211         temp = 0;
01212         for (j = 0; j < i; j++)
01213             temp -= lpc[j] * autocorr[i - j - 1];
01214         temp = ((autocorr[i] << 13) + temp) << 3;
01215 
01216         if (FFABS(temp) >= (error << 16))
01217             break;
01218 
01219         partial_corr = temp / (error << 1);
01220 
01221         lpc[i] = av_clipl_int32((int64_t)(partial_corr << 14) +
01222                                 (1 << 15)) >> 16;
01223 
01224         /* Update the prediction error */
01225         temp  = MULL2(temp, partial_corr);
01226         error = av_clipl_int32((int64_t)(error << 16) - temp +
01227                                 (1 << 15)) >> 16;
01228 
01229         memcpy(vector, lpc, i * sizeof(int16_t));
01230         for (j = 0; j < i; j++) {
01231             temp = partial_corr * vector[i - j - 1] << 1;
01232             lpc[j] = av_clipl_int32((int64_t)(lpc[j] << 16) - temp +
01233                                     (1 << 15)) >> 16;
01234         }
01235     }
01236 }
01237 
01245 static void comp_lpc_coeff(int16_t *buf, int16_t *lpc)
01246 {
01247     int16_t autocorr[(LPC_ORDER + 1) * SUBFRAMES];
01248     int16_t *autocorr_ptr = autocorr;
01249     int16_t *lpc_ptr      = lpc;
01250     int i, j;
01251 
01252     for (i = 0, j = 0; j < SUBFRAMES; i += SUBFRAME_LEN, j++) {
01253         comp_autocorr(buf + i, autocorr_ptr);
01254         levinson_durbin(lpc_ptr, autocorr_ptr + 1, autocorr_ptr[0]);
01255 
01256         lpc_ptr += LPC_ORDER;
01257         autocorr_ptr += LPC_ORDER + 1;
01258     }
01259 }
01260 
01261 static void lpc2lsp(int16_t *lpc, int16_t *prev_lsp, int16_t *lsp)
01262 {
01263     int f[LPC_ORDER + 2]; 
01264 
01265 
01266 
01267     int max, shift, cur_val, prev_val, count, p;
01268     int i, j;
01269     int64_t temp;
01270 
01271     /* Initialize f1[0] and f2[0] to 1 in Q25 */
01272     for (i = 0; i < LPC_ORDER; i++)
01273         lsp[i] = (lpc[i] * bandwidth_expand[i] + (1 << 14)) >> 15;
01274 
01275     /* Apply bandwidth expansion on the LPC coefficients */
01276     f[0] = f[1] = 1 << 25;
01277 
01278     /* Compute the remaining coefficients */
01279     for (i = 0; i < LPC_ORDER / 2; i++) {
01280         /* f1 */
01281         f[2 * i + 2] = -f[2 * i] - ((lsp[i] + lsp[LPC_ORDER - 1 - i]) << 12);
01282         /* f2 */
01283         f[2 * i + 3] = f[2 * i + 1] - ((lsp[i] - lsp[LPC_ORDER - 1 - i]) << 12);
01284     }
01285 
01286     /* Divide f1[5] and f2[5] by 2 for use in polynomial evaluation */
01287     f[LPC_ORDER] >>= 1;
01288     f[LPC_ORDER + 1] >>= 1;
01289 
01290     /* Normalize and shorten */
01291     max = FFABS(f[0]);
01292     for (i = 1; i < LPC_ORDER + 2; i++)
01293         max = FFMAX(max, FFABS(f[i]));
01294 
01295     shift = normalize_bits_int32(max);
01296 
01297     for (i = 0; i < LPC_ORDER + 2; i++)
01298         f[i] = av_clipl_int32((int64_t)(f[i] << shift) + (1 << 15)) >> 16;
01299 
01304     p    = 0;
01305     temp = 0;
01306     for (i = 0; i <= LPC_ORDER / 2; i++)
01307         temp += f[2 * i] * cos_tab[0];
01308     prev_val = av_clipl_int32(temp << 1);
01309     count    = 0;
01310     for ( i = 1; i < COS_TBL_SIZE / 2; i++) {
01311         /* Evaluate */
01312         temp = 0;
01313         for (j = 0; j <= LPC_ORDER / 2; j++)
01314             temp += f[LPC_ORDER - 2 * j + p] * cos_tab[i * j % COS_TBL_SIZE];
01315         cur_val = av_clipl_int32(temp << 1);
01316 
01317         /* Check for sign change, indicating a zero crossing */
01318         if ((cur_val ^ prev_val) < 0) {
01319             int abs_cur  = FFABS(cur_val);
01320             int abs_prev = FFABS(prev_val);
01321             int sum      = abs_cur + abs_prev;
01322 
01323             shift        = normalize_bits_int32(sum);
01324             sum          <<= shift;
01325             abs_prev     = abs_prev << shift >> 8;
01326             lsp[count++] = ((i - 1) << 7) + (abs_prev >> 1) / (sum >> 16);
01327 
01328             if (count == LPC_ORDER)
01329                 break;
01330 
01331             /* Switch between sum and difference polynomials */
01332             p ^= 1;
01333 
01334             /* Evaluate */
01335             temp = 0;
01336             for (j = 0; j <= LPC_ORDER / 2; j++){
01337                 temp += f[LPC_ORDER - 2 * j + p] *
01338                         cos_tab[i * j % COS_TBL_SIZE];
01339             }
01340             cur_val = av_clipl_int32(temp<<1);
01341         }
01342         prev_val = cur_val;
01343     }
01344 
01345     if (count != LPC_ORDER)
01346         memcpy(lsp, prev_lsp, LPC_ORDER * sizeof(int16_t));
01347 }
01348 
01356 #define get_index(num, offset, size) \
01357 {\
01358     int error, max = -1;\
01359     int16_t temp[4];\
01360     int i, j;\
01361     for (i = 0; i < LSP_CB_SIZE; i++) {\
01362         for (j = 0; j < size; j++){\
01363             temp[j] = (weight[j + (offset)] * lsp_band##num[i][j] +\
01364                       (1 << 14)) >> 15;\
01365         }\
01366         error =  dot_product(lsp + (offset), temp, size, 1) << 1;\
01367         error -= dot_product(lsp_band##num[i], temp, size, 1);\
01368         if (error > max) {\
01369             max = error;\
01370             lsp_index[num] = i;\
01371         }\
01372     }\
01373 }
01374 
01381 static void lsp_quantize(uint8_t *lsp_index, int16_t *lsp, int16_t *prev_lsp)
01382 {
01383     int16_t weight[LPC_ORDER];
01384     int16_t min, max;
01385     int shift, i;
01386 
01387     /* Calculate the VQ weighting vector */
01388     weight[0] = (1 << 20) / (lsp[1] - lsp[0]);
01389     weight[LPC_ORDER - 1] = (1 << 20) /
01390                             (lsp[LPC_ORDER - 1] - lsp[LPC_ORDER - 2]);
01391 
01392     for (i = 1; i < LPC_ORDER - 1; i++) {
01393         min  = FFMIN(lsp[i] - lsp[i - 1], lsp[i + 1] - lsp[i]);
01394         if (min > 0x20)
01395             weight[i] = (1 << 20) / min;
01396         else
01397             weight[i] = INT16_MAX;
01398     }
01399 
01400     /* Normalize */
01401     max = 0;
01402     for (i = 0; i < LPC_ORDER; i++)
01403         max = FFMAX(weight[i], max);
01404 
01405     shift = normalize_bits_int16(max);
01406     for (i = 0; i < LPC_ORDER; i++) {
01407         weight[i] <<= shift;
01408     }
01409 
01410     /* Compute the VQ target vector */
01411     for (i = 0; i < LPC_ORDER; i++) {
01412         lsp[i] -= dc_lsp[i] +
01413                   (((prev_lsp[i] - dc_lsp[i]) * 12288 + (1 << 14)) >> 15);
01414     }
01415 
01416     get_index(0, 0, 3);
01417     get_index(1, 3, 3);
01418     get_index(2, 6, 4);
01419 }
01420 
01427 static void perceptual_filter(G723_1_Context *p, int16_t *flt_coef,
01428                               int16_t *unq_lpc, int16_t *buf)
01429 {
01430     int16_t vector[FRAME_LEN + LPC_ORDER];
01431     int i, j, k, l = 0;
01432 
01433     memcpy(buf, p->iir_mem, sizeof(int16_t) * LPC_ORDER);
01434     memcpy(vector, p->fir_mem, sizeof(int16_t) * LPC_ORDER);
01435     memcpy(vector + LPC_ORDER, buf + LPC_ORDER, sizeof(int16_t) * FRAME_LEN);
01436 
01437     for (i = LPC_ORDER, j = 0; j < SUBFRAMES; i += SUBFRAME_LEN, j++) {
01438         for (k = 0; k < LPC_ORDER; k++) {
01439             flt_coef[k + 2 * l] = (unq_lpc[k + l] * percept_flt_tbl[0][k] +
01440                                   (1 << 14)) >> 15;
01441             flt_coef[k + 2 * l + LPC_ORDER] = (unq_lpc[k + l] *
01442                                              percept_flt_tbl[1][k] +
01443                                              (1 << 14)) >> 15;
01444         }
01445         iir_filter(flt_coef + 2 * l, flt_coef + 2 * l + LPC_ORDER, vector + i,
01446                    buf + i, 0);
01447         l += LPC_ORDER;
01448     }
01449     memcpy(p->iir_mem, buf + FRAME_LEN, sizeof(int16_t) * LPC_ORDER);
01450     memcpy(p->fir_mem, vector + FRAME_LEN, sizeof(int16_t) * LPC_ORDER);
01451 }
01452 
01459 static int estimate_pitch(int16_t *buf, int start)
01460 {
01461     int max_exp = 32;
01462     int max_ccr = 0x4000;
01463     int max_eng = 0x7fff;
01464     int index   = PITCH_MIN;
01465     int offset  = start - PITCH_MIN + 1;
01466 
01467     int ccr, eng, orig_eng, ccr_eng, exp;
01468     int diff, temp;
01469 
01470     int i;
01471 
01472     orig_eng = dot_product(buf + offset, buf + offset, HALF_FRAME_LEN, 0);
01473 
01474     for (i = PITCH_MIN; i <= PITCH_MAX - 3; i++) {
01475         offset--;
01476 
01477         /* Update energy and compute correlation */
01478         orig_eng += buf[offset] * buf[offset] -
01479                     buf[offset + HALF_FRAME_LEN] * buf[offset + HALF_FRAME_LEN];
01480         ccr      =  dot_product(buf + start, buf + offset, HALF_FRAME_LEN, 0);
01481         if (ccr <= 0)
01482             continue;
01483 
01484         /* Split into mantissa and exponent to maintain precision */
01485         exp  =   normalize_bits_int32(ccr);
01486         ccr  =   av_clipl_int32((int64_t)(ccr << exp) + (1 << 15)) >> 16;
01487         exp  <<= 1;
01488         ccr  *=  ccr;
01489         temp =   normalize_bits_int32(ccr);
01490         ccr  =   ccr << temp >> 16;
01491         exp  +=  temp;
01492 
01493         temp =   normalize_bits_int32(orig_eng);
01494         eng  =   av_clipl_int32((int64_t)(orig_eng << temp) + (1 << 15)) >> 16;
01495         exp  -=  temp;
01496 
01497         if (ccr >= eng) {
01498             exp--;
01499             ccr >>= 1;
01500         }
01501         if (exp > max_exp)
01502             continue;
01503 
01504         if (exp + 1 < max_exp)
01505             goto update;
01506 
01507         /* Equalize exponents before comparison */
01508         if (exp + 1 == max_exp)
01509             temp = max_ccr >> 1;
01510         else
01511             temp = max_ccr;
01512         ccr_eng = ccr * max_eng;
01513         diff    = ccr_eng - eng * temp;
01514         if (diff > 0 && (i - index < PITCH_MIN || diff > ccr_eng >> 2)) {
01515 update:
01516             index   = i;
01517             max_exp = exp;
01518             max_ccr = ccr;
01519             max_eng = eng;
01520         }
01521     }
01522     return index;
01523 }
01524 
01532 static void comp_harmonic_coeff(int16_t *buf, int16_t pitch_lag, HFParam *hf)
01533 {
01534     int ccr, eng, max_ccr, max_eng;
01535     int exp, max, diff;
01536     int energy[15];
01537     int i, j;
01538 
01539     for (i = 0, j = pitch_lag - 3; j <= pitch_lag + 3; i++, j++) {
01540         /* Compute residual energy */
01541         energy[i << 1] = dot_product(buf - j, buf - j, SUBFRAME_LEN, 0);
01542         /* Compute correlation */
01543         energy[(i << 1) + 1] = dot_product(buf, buf - j, SUBFRAME_LEN, 0);
01544     }
01545 
01546     /* Compute target energy */
01547     energy[14] = dot_product(buf, buf, SUBFRAME_LEN, 0);
01548 
01549     /* Normalize */
01550     max = 0;
01551     for (i = 0; i < 15; i++)
01552         max = FFMAX(max, FFABS(energy[i]));
01553 
01554     exp = normalize_bits_int32(max);
01555     for (i = 0; i < 15; i++) {
01556         energy[i] = av_clipl_int32((int64_t)(energy[i] << exp) +
01557                                    (1 << 15)) >> 16;
01558     }
01559 
01560     hf->index = -1;
01561     hf->gain  =  0;
01562     max_ccr   =  1;
01563     max_eng   =  0x7fff;
01564 
01565     for (i = 0; i <= 6; i++) {
01566         eng = energy[i << 1];
01567         ccr = energy[(i << 1) + 1];
01568 
01569         if (ccr <= 0)
01570             continue;
01571 
01572         ccr  = (ccr * ccr + (1 << 14)) >> 15;
01573         diff = ccr * max_eng - eng * max_ccr;
01574         if (diff > 0) {
01575             max_ccr   = ccr;
01576             max_eng   = eng;
01577             hf->index = i;
01578         }
01579     }
01580 
01581     if (hf->index == -1) {
01582         hf->index = pitch_lag;
01583         return;
01584     }
01585 
01586     eng = energy[14] * max_eng;
01587     eng = (eng >> 2) + (eng >> 3);
01588     ccr = energy[(hf->index << 1) + 1] * energy[(hf->index << 1) + 1];
01589     if (eng < ccr) {
01590         eng = energy[(hf->index << 1) + 1];
01591 
01592         if (eng >= max_eng)
01593             hf->gain = 0x2800;
01594         else
01595             hf->gain = ((eng << 15) / max_eng * 0x2800 + (1 << 14)) >> 15;
01596     }
01597     hf->index += pitch_lag - 3;
01598 }
01599 
01605 static void harmonic_filter(HFParam *hf, int16_t *src, int16_t *dest)
01606 {
01607     int i;
01608 
01609     for (i = 0; i < SUBFRAME_LEN; i++) {
01610         int64_t temp = hf->gain * src[i - hf->index] << 1;
01611         dest[i] = av_clipl_int32((src[i] << 16) - temp + (1 << 15)) >> 16;
01612     }
01613 }
01614 
01615 static void harmonic_noise_sub(HFParam *hf, int16_t *src, int16_t *dest)
01616 {
01617     int i;
01618     for (i = 0; i < SUBFRAME_LEN; i++) {
01619         int64_t temp = hf->gain * src[i - hf->index] << 1;
01620         dest[i] = av_clipl_int32(((dest[i] - src[i]) << 16) + temp +
01621                                  (1 << 15)) >> 16;
01622 
01623     }
01624 }
01625 
01635 static void synth_percept_filter(int16_t *qnt_lpc, int16_t *perf_lpc,
01636                                  int16_t *perf_fir, int16_t *perf_iir,
01637                                  int16_t *src, int16_t *dest, int scale)
01638 {
01639     int i, j;
01640     int16_t buf_16[SUBFRAME_LEN + LPC_ORDER];
01641     int64_t buf[SUBFRAME_LEN];
01642 
01643     int16_t *bptr_16 = buf_16 + LPC_ORDER;
01644 
01645     memcpy(buf_16, perf_fir, sizeof(int16_t) * LPC_ORDER);
01646     memcpy(dest - LPC_ORDER, perf_iir, sizeof(int16_t) * LPC_ORDER);
01647 
01648     for (i = 0; i < SUBFRAME_LEN; i++) {
01649         int64_t temp = 0;
01650         for (j = 1; j <= LPC_ORDER; j++)
01651             temp -= qnt_lpc[j - 1] * bptr_16[i - j];
01652 
01653         buf[i]     = (src[i] << 15) + (temp << 3);
01654         bptr_16[i] = av_clipl_int32(buf[i] + (1 << 15)) >> 16;
01655     }
01656 
01657     for (i = 0; i < SUBFRAME_LEN; i++) {
01658         int64_t fir = 0, iir = 0;
01659         for (j = 1; j <= LPC_ORDER; j++) {
01660             fir -= perf_lpc[j - 1] * bptr_16[i - j];
01661             iir += perf_lpc[j + LPC_ORDER - 1] * dest[i - j];
01662         }
01663         dest[i] = av_clipl_int32(((buf[i] + (fir << 3)) << scale) + (iir << 3) +
01664                                  (1 << 15)) >> 16;
01665     }
01666     memcpy(perf_fir, buf_16 + SUBFRAME_LEN, sizeof(int16_t) * LPC_ORDER);
01667     memcpy(perf_iir, dest + SUBFRAME_LEN - LPC_ORDER,
01668            sizeof(int16_t) * LPC_ORDER);
01669 }
01670 
01677 static void acb_search(G723_1_Context *p, int16_t *residual,
01678                        int16_t *impulse_resp, int16_t *buf,
01679                        int index)
01680 {
01681 
01682     int16_t flt_buf[PITCH_ORDER][SUBFRAME_LEN];
01683 
01684     const int16_t *cb_tbl = adaptive_cb_gain85;
01685 
01686     int ccr_buf[PITCH_ORDER * SUBFRAMES << 2];
01687 
01688     int pitch_lag = p->pitch_lag[index >> 1];
01689     int acb_lag   = 1;
01690     int acb_gain  = 0;
01691     int odd_frame = index & 1;
01692     int iter      = 3 + odd_frame;
01693     int count     = 0;
01694     int tbl_size  = 85;
01695 
01696     int i, j, k, l, max;
01697     int64_t temp;
01698 
01699     if (!odd_frame) {
01700         if (pitch_lag == PITCH_MIN)
01701             pitch_lag++;
01702         else
01703             pitch_lag = FFMIN(pitch_lag, PITCH_MAX - 5);
01704     }
01705 
01706     for (i = 0; i < iter; i++) {
01707         get_residual(residual, p->prev_excitation, pitch_lag + i - 1);
01708 
01709         for (j = 0; j < SUBFRAME_LEN; j++) {
01710             temp = 0;
01711             for (k = 0; k <= j; k++)
01712                 temp += residual[PITCH_ORDER - 1 + k] * impulse_resp[j - k];
01713             flt_buf[PITCH_ORDER - 1][j] = av_clipl_int32((temp << 1) +
01714                                                          (1 << 15)) >> 16;
01715         }
01716 
01717         for (j = PITCH_ORDER - 2; j >= 0; j--) {
01718             flt_buf[j][0] = ((residual[j] << 13) + (1 << 14)) >> 15;
01719             for (k = 1; k < SUBFRAME_LEN; k++) {
01720                 temp = (flt_buf[j + 1][k - 1] << 15) +
01721                        residual[j] * impulse_resp[k];
01722                 flt_buf[j][k] = av_clipl_int32((temp << 1) + (1 << 15)) >> 16;
01723             }
01724         }
01725 
01726         /* Compute crosscorrelation with the signal */
01727         for (j = 0; j < PITCH_ORDER; j++) {
01728             temp = dot_product(buf, flt_buf[j], SUBFRAME_LEN, 0);
01729             ccr_buf[count++] = av_clipl_int32(temp << 1);
01730         }
01731 
01732         /* Compute energies */
01733         for (j = 0; j < PITCH_ORDER; j++) {
01734             ccr_buf[count++] = dot_product(flt_buf[j], flt_buf[j],
01735                                            SUBFRAME_LEN, 1);
01736         }
01737 
01738         for (j = 1; j < PITCH_ORDER; j++) {
01739             for (k = 0; k < j; k++) {
01740                 temp = dot_product(flt_buf[j], flt_buf[k], SUBFRAME_LEN, 0);
01741                 ccr_buf[count++] = av_clipl_int32(temp<<2);
01742             }
01743         }
01744     }
01745 
01746     /* Normalize and shorten */
01747     max = 0;
01748     for (i = 0; i < 20 * iter; i++)
01749         max = FFMAX(max, FFABS(ccr_buf[i]));
01750 
01751     temp = normalize_bits_int32(max);
01752 
01753     for (i = 0; i < 20 * iter; i++){
01754         ccr_buf[i] = av_clipl_int32((int64_t)(ccr_buf[i] << temp) +
01755                                     (1 << 15)) >> 16;
01756     }
01757 
01758     max = 0;
01759     for (i = 0; i < iter; i++) {
01760         /* Select quantization table */
01761         if (!odd_frame && pitch_lag + i - 1 >= SUBFRAME_LEN - 2 ||
01762             odd_frame && pitch_lag >= SUBFRAME_LEN - 2) {
01763             cb_tbl = adaptive_cb_gain170;
01764             tbl_size = 170;
01765         }
01766 
01767         for (j = 0, k = 0; j < tbl_size; j++, k += 20) {
01768             temp = 0;
01769             for (l = 0; l < 20; l++)
01770                 temp += ccr_buf[20 * i + l] * cb_tbl[k + l];
01771             temp =  av_clipl_int32(temp);
01772 
01773             if (temp > max) {
01774                 max      = temp;
01775                 acb_gain = j;
01776                 acb_lag  = i;
01777             }
01778         }
01779     }
01780 
01781     if (!odd_frame) {
01782         pitch_lag += acb_lag - 1;
01783         acb_lag   =  1;
01784     }
01785 
01786     p->pitch_lag[index >> 1]      = pitch_lag;
01787     p->subframe[index].ad_cb_lag  = acb_lag;
01788     p->subframe[index].ad_cb_gain = acb_gain;
01789 }
01790 
01797 static void sub_acb_contrib(int16_t *residual, int16_t *impulse_resp,
01798                             int16_t *buf)
01799 {
01800     int i, j;
01801     /* Subtract adaptive CB contribution to obtain the residual */
01802     for (i = 0; i < SUBFRAME_LEN; i++) {
01803         int64_t temp = buf[i] << 14;
01804         for (j = 0; j <= i; j++)
01805             temp -= residual[j] * impulse_resp[i - j];
01806 
01807         buf[i] = av_clipl_int32((temp << 2) + (1 << 15)) >> 16;
01808     }
01809 }
01810 
01817 static void get_fcb_param(FCBParam *optim, int16_t *impulse_resp,
01818                           int16_t *buf, int pulse_cnt, int pitch_lag)
01819 {
01820     FCBParam param;
01821     int16_t impulse_r[SUBFRAME_LEN];
01822     int16_t temp_corr[SUBFRAME_LEN];
01823     int16_t impulse_corr[SUBFRAME_LEN];
01824 
01825     int ccr1[SUBFRAME_LEN];
01826     int ccr2[SUBFRAME_LEN];
01827     int amp, err, max, max_amp_index, min, scale, i, j, k, l;
01828 
01829     int64_t temp;
01830 
01831     /* Update impulse response */
01832     memcpy(impulse_r, impulse_resp, sizeof(int16_t) * SUBFRAME_LEN);
01833     param.dirac_train = 0;
01834     if (pitch_lag < SUBFRAME_LEN - 2) {
01835         param.dirac_train = 1;
01836         gen_dirac_train(impulse_r, pitch_lag);
01837     }
01838 
01839     for (i = 0; i < SUBFRAME_LEN; i++)
01840         temp_corr[i] = impulse_r[i] >> 1;
01841 
01842     /* Compute impulse response autocorrelation */
01843     temp = dot_product(temp_corr, temp_corr, SUBFRAME_LEN, 1);
01844 
01845     scale = normalize_bits_int32(temp);
01846     impulse_corr[0] = av_clipl_int32((temp << scale) + (1 << 15)) >> 16;
01847 
01848     for (i = 1; i < SUBFRAME_LEN; i++) {
01849         temp = dot_product(temp_corr + i, temp_corr, SUBFRAME_LEN - i, 1);
01850         impulse_corr[i] = av_clipl_int32((temp << scale) + (1 << 15)) >> 16;
01851     }
01852 
01853     /* Compute crosscorrelation of impulse response with residual signal */
01854     scale -= 4;
01855     for (i = 0; i < SUBFRAME_LEN; i++){
01856         temp = dot_product(buf + i, impulse_r, SUBFRAME_LEN - i, 1);
01857         if (scale < 0)
01858             ccr1[i] = temp >> -scale;
01859         else
01860             ccr1[i] = av_clipl_int32(temp << scale);
01861     }
01862 
01863     /* Search loop */
01864     for (i = 0; i < GRID_SIZE; i++) {
01865         /* Maximize the crosscorrelation */
01866         max = 0;
01867         for (j = i; j < SUBFRAME_LEN; j += GRID_SIZE) {
01868             temp = FFABS(ccr1[j]);
01869             if (temp >= max) {
01870                 max = temp;
01871                 param.pulse_pos[0] = j;
01872             }
01873         }
01874 
01875         /* Quantize the gain (max crosscorrelation/impulse_corr[0]) */
01876         amp = max;
01877         min = 1 << 30;
01878         max_amp_index = GAIN_LEVELS - 2;
01879         for (j = max_amp_index; j >= 2; j--) {
01880             temp = av_clipl_int32((int64_t)fixed_cb_gain[j] *
01881                                   impulse_corr[0] << 1);
01882             temp = FFABS(temp - amp);
01883             if (temp < min) {
01884                 min = temp;
01885                 max_amp_index = j;
01886             }
01887         }
01888 
01889         max_amp_index--;
01890         /* Select additional gain values */
01891         for (j = 1; j < 5; j++) {
01892             for (k = i; k < SUBFRAME_LEN; k += GRID_SIZE) {
01893                 temp_corr[k] = 0;
01894                 ccr2[k]      = ccr1[k];
01895             }
01896             param.amp_index = max_amp_index + j - 2;
01897             amp = fixed_cb_gain[param.amp_index];
01898 
01899             param.pulse_sign[0] = (ccr2[param.pulse_pos[0]] < 0) ? -amp : amp;
01900             temp_corr[param.pulse_pos[0]] = 1;
01901 
01902             for (k = 1; k < pulse_cnt; k++) {
01903                 max = -1 << 30;
01904                 for (l = i; l < SUBFRAME_LEN; l += GRID_SIZE) {
01905                     if (temp_corr[l])
01906                         continue;
01907                     temp = impulse_corr[FFABS(l - param.pulse_pos[k - 1])];
01908                     temp = av_clipl_int32((int64_t)temp *
01909                                           param.pulse_sign[k - 1] << 1);
01910                     ccr2[l] -= temp;
01911                     temp = FFABS(ccr2[l]);
01912                     if (temp > max) {
01913                         max = temp;
01914                         param.pulse_pos[k] = l;
01915                     }
01916                 }
01917 
01918                 param.pulse_sign[k] = (ccr2[param.pulse_pos[k]] < 0) ?
01919                                       -amp : amp;
01920                 temp_corr[param.pulse_pos[k]] = 1;
01921             }
01922 
01923             /* Create the error vector */
01924             memset(temp_corr, 0, sizeof(int16_t) * SUBFRAME_LEN);
01925 
01926             for (k = 0; k < pulse_cnt; k++)
01927                 temp_corr[param.pulse_pos[k]] = param.pulse_sign[k];
01928 
01929             for (k = SUBFRAME_LEN - 1; k >= 0; k--) {
01930                 temp = 0;
01931                 for (l = 0; l <= k; l++) {
01932                     int prod = av_clipl_int32((int64_t)temp_corr[l] *
01933                                               impulse_r[k - l] << 1);
01934                     temp     = av_clipl_int32(temp + prod);
01935                 }
01936                 temp_corr[k] = temp << 2 >> 16;
01937             }
01938 
01939             /* Compute square of error */
01940             err = 0;
01941             for (k = 0; k < SUBFRAME_LEN; k++) {
01942                 int64_t prod;
01943                 prod = av_clipl_int32((int64_t)buf[k] * temp_corr[k] << 1);
01944                 err  = av_clipl_int32(err - prod);
01945                 prod = av_clipl_int32((int64_t)temp_corr[k] * temp_corr[k]);
01946                 err  = av_clipl_int32(err + prod);
01947             }
01948 
01949             /* Minimize */
01950             if (err < optim->min_err) {
01951                 optim->min_err     = err;
01952                 optim->grid_index  = i;
01953                 optim->amp_index   = param.amp_index;
01954                 optim->dirac_train = param.dirac_train;
01955 
01956                 for (k = 0; k < pulse_cnt; k++) {
01957                     optim->pulse_sign[k] = param.pulse_sign[k];
01958                     optim->pulse_pos[k]  = param.pulse_pos[k];
01959                 }
01960             }
01961         }
01962     }
01963 }
01964 
01971 static void pack_fcb_param(G723_1_Subframe *subfrm, FCBParam *optim,
01972                            int16_t *buf, int pulse_cnt)
01973 {
01974     int i, j;
01975 
01976     j = PULSE_MAX - pulse_cnt;
01977 
01978     subfrm->pulse_sign = 0;
01979     subfrm->pulse_pos  = 0;
01980 
01981     for (i = 0; i < SUBFRAME_LEN >> 1; i++) {
01982         int val = buf[optim->grid_index + (i << 1)];
01983         if (!val) {
01984             subfrm->pulse_pos += combinatorial_table[j][i];
01985         } else {
01986             subfrm->pulse_sign <<= 1;
01987             if (val < 0) subfrm->pulse_sign++;
01988             j++;
01989 
01990             if (j == PULSE_MAX) break;
01991         }
01992     }
01993     subfrm->amp_index   = optim->amp_index;
01994     subfrm->grid_index  = optim->grid_index;
01995     subfrm->dirac_train = optim->dirac_train;
01996 }
01997 
02004 static void fcb_search(G723_1_Context *p, int16_t *impulse_resp,
02005                        int16_t *buf, int index)
02006 {
02007     FCBParam optim;
02008     int pulse_cnt = pulses[index];
02009     int i;
02010 
02011     optim.min_err = 1 << 30;
02012     get_fcb_param(&optim, impulse_resp, buf, pulse_cnt, SUBFRAME_LEN);
02013 
02014     if (p->pitch_lag[index >> 1] < SUBFRAME_LEN - 2) {
02015         get_fcb_param(&optim, impulse_resp, buf, pulse_cnt,
02016                       p->pitch_lag[index >> 1]);
02017     }
02018 
02019     /* Reconstruct the excitation */
02020     memset(buf, 0, sizeof(int16_t) * SUBFRAME_LEN);
02021     for (i = 0; i < pulse_cnt; i++)
02022         buf[optim.pulse_pos[i]] = optim.pulse_sign[i];
02023 
02024     pack_fcb_param(&p->subframe[index], &optim, buf, pulse_cnt);
02025 
02026     if (optim.dirac_train)
02027         gen_dirac_train(buf, p->pitch_lag[index >> 1]);
02028 }
02029 
02036 static int pack_bitstream(G723_1_Context *p, unsigned char *frame, int size)
02037 {
02038     PutBitContext pb;
02039     int info_bits, i, temp;
02040 
02041     init_put_bits(&pb, frame, size);
02042 
02043     if (p->cur_rate == Rate6k3) {
02044         info_bits = 0;
02045         put_bits(&pb, 2, info_bits);
02046     }
02047 
02048     put_bits(&pb, 8, p->lsp_index[2]);
02049     put_bits(&pb, 8, p->lsp_index[1]);
02050     put_bits(&pb, 8, p->lsp_index[0]);
02051 
02052     put_bits(&pb, 7, p->pitch_lag[0] - PITCH_MIN);
02053     put_bits(&pb, 2, p->subframe[1].ad_cb_lag);
02054     put_bits(&pb, 7, p->pitch_lag[1] - PITCH_MIN);
02055     put_bits(&pb, 2, p->subframe[3].ad_cb_lag);
02056 
02057     /* Write 12 bit combined gain */
02058     for (i = 0; i < SUBFRAMES; i++) {
02059         temp = p->subframe[i].ad_cb_gain * GAIN_LEVELS +
02060                p->subframe[i].amp_index;
02061         if (p->cur_rate ==  Rate6k3)
02062             temp += p->subframe[i].dirac_train << 11;
02063         put_bits(&pb, 12, temp);
02064     }
02065 
02066     put_bits(&pb, 1, p->subframe[0].grid_index);
02067     put_bits(&pb, 1, p->subframe[1].grid_index);
02068     put_bits(&pb, 1, p->subframe[2].grid_index);
02069     put_bits(&pb, 1, p->subframe[3].grid_index);
02070 
02071     if (p->cur_rate == Rate6k3) {
02072         skip_put_bits(&pb, 1); /* reserved bit */
02073 
02074         /* Write 13 bit combined position index */
02075         temp = (p->subframe[0].pulse_pos >> 16) * 810 +
02076                (p->subframe[1].pulse_pos >> 14) *  90 +
02077                (p->subframe[2].pulse_pos >> 16) *   9 +
02078                (p->subframe[3].pulse_pos >> 14);
02079         put_bits(&pb, 13, temp);
02080 
02081         put_bits(&pb, 16, p->subframe[0].pulse_pos & 0xffff);
02082         put_bits(&pb, 14, p->subframe[1].pulse_pos & 0x3fff);
02083         put_bits(&pb, 16, p->subframe[2].pulse_pos & 0xffff);
02084         put_bits(&pb, 14, p->subframe[3].pulse_pos & 0x3fff);
02085 
02086         put_bits(&pb, 6, p->subframe[0].pulse_sign);
02087         put_bits(&pb, 5, p->subframe[1].pulse_sign);
02088         put_bits(&pb, 6, p->subframe[2].pulse_sign);
02089         put_bits(&pb, 5, p->subframe[3].pulse_sign);
02090     }
02091 
02092     flush_put_bits(&pb);
02093     return frame_size[info_bits];
02094 }
02095 
02096 static int g723_1_encode_frame(AVCodecContext *avctx, unsigned char *buf,
02097                                int buf_size, void *data)
02098 {
02099     G723_1_Context *p = avctx->priv_data;
02100     int16_t unq_lpc[LPC_ORDER * SUBFRAMES];
02101     int16_t qnt_lpc[LPC_ORDER * SUBFRAMES];
02102     int16_t cur_lsp[LPC_ORDER];
02103     int16_t weighted_lpc[LPC_ORDER * SUBFRAMES << 1];
02104     int16_t vector[FRAME_LEN + PITCH_MAX];
02105     int offset;
02106     int16_t *in = data;
02107 
02108     HFParam hf[4];
02109     int i, j;
02110 
02111     highpass_filter(in, &p->hpf_fir_mem, &p->hpf_iir_mem);
02112 
02113     memcpy(vector, p->prev_data, HALF_FRAME_LEN * sizeof(int16_t));
02114     memcpy(vector + HALF_FRAME_LEN, in, FRAME_LEN * sizeof(int16_t));
02115 
02116     comp_lpc_coeff(vector, unq_lpc);
02117     lpc2lsp(&unq_lpc[LPC_ORDER * 3], p->prev_lsp, cur_lsp);
02118     lsp_quantize(p->lsp_index, cur_lsp, p->prev_lsp);
02119 
02120     /* Update memory */
02121     memcpy(vector + LPC_ORDER, p->prev_data + SUBFRAME_LEN,
02122            sizeof(int16_t) * SUBFRAME_LEN);
02123     memcpy(vector + LPC_ORDER + SUBFRAME_LEN, in,
02124            sizeof(int16_t) * (HALF_FRAME_LEN + SUBFRAME_LEN));
02125     memcpy(p->prev_data, in + HALF_FRAME_LEN,
02126            sizeof(int16_t) * HALF_FRAME_LEN);
02127     memcpy(in, vector + LPC_ORDER, sizeof(int16_t) * FRAME_LEN);
02128 
02129     perceptual_filter(p, weighted_lpc, unq_lpc, vector);
02130 
02131     memcpy(in, vector + LPC_ORDER, sizeof(int16_t) * FRAME_LEN);
02132     memcpy(vector, p->prev_weight_sig, sizeof(int16_t) * PITCH_MAX);
02133     memcpy(vector + PITCH_MAX, in, sizeof(int16_t) * FRAME_LEN);
02134 
02135     scale_vector(vector, FRAME_LEN + PITCH_MAX);
02136 
02137     p->pitch_lag[0] = estimate_pitch(vector, PITCH_MAX);
02138     p->pitch_lag[1] = estimate_pitch(vector, PITCH_MAX + HALF_FRAME_LEN);
02139 
02140     for (i = PITCH_MAX, j = 0; j < SUBFRAMES; i += SUBFRAME_LEN, j++)
02141         comp_harmonic_coeff(vector + i, p->pitch_lag[j >> 1], hf + j);
02142 
02143     memcpy(vector, p->prev_weight_sig, sizeof(int16_t) * PITCH_MAX);
02144     memcpy(vector + PITCH_MAX, in, sizeof(int16_t) * FRAME_LEN);
02145     memcpy(p->prev_weight_sig, vector + FRAME_LEN, sizeof(int16_t) * PITCH_MAX);
02146 
02147     for (i = 0, j = 0; j < SUBFRAMES; i += SUBFRAME_LEN, j++)
02148         harmonic_filter(hf + j, vector + PITCH_MAX + i, in + i);
02149 
02150     inverse_quant(cur_lsp, p->prev_lsp, p->lsp_index, 0);
02151     lsp_interpolate(qnt_lpc, cur_lsp, p->prev_lsp);
02152 
02153     memcpy(p->prev_lsp, cur_lsp, sizeof(int16_t) * LPC_ORDER);
02154 
02155     offset = 0;
02156     for (i = 0; i < SUBFRAMES; i++) {
02157         int16_t impulse_resp[SUBFRAME_LEN];
02158         int16_t residual[SUBFRAME_LEN + PITCH_ORDER - 1];
02159         int16_t flt_in[SUBFRAME_LEN];
02160         int16_t zero[LPC_ORDER], fir[LPC_ORDER], iir[LPC_ORDER];
02161 
02166         memset(zero, 0, sizeof(int16_t) * LPC_ORDER);
02167         memset(vector, 0, sizeof(int16_t) * PITCH_MAX);
02168         memset(flt_in, 0, sizeof(int16_t) * SUBFRAME_LEN);
02169 
02170         flt_in[0] = 1 << 13; /* Unit impulse */
02171         synth_percept_filter(qnt_lpc + offset, weighted_lpc + (offset << 1),
02172                              zero, zero, flt_in, vector + PITCH_MAX, 1);
02173         harmonic_filter(hf + i, vector + PITCH_MAX, impulse_resp);
02174 
02175          /* Compute the combined zero input response */
02176         flt_in[0] = 0;
02177         memcpy(fir, p->perf_fir_mem, sizeof(int16_t) * LPC_ORDER);
02178         memcpy(iir, p->perf_iir_mem, sizeof(int16_t) * LPC_ORDER);
02179 
02180         synth_percept_filter(qnt_lpc + offset, weighted_lpc + (offset << 1),
02181                              fir, iir, flt_in, vector + PITCH_MAX, 0);
02182         memcpy(vector, p->harmonic_mem, sizeof(int16_t) * PITCH_MAX);
02183         harmonic_noise_sub(hf + i, vector + PITCH_MAX, in);
02184 
02185         acb_search(p, residual, impulse_resp, in, i);
02186         gen_acb_excitation(residual, p->prev_excitation,p->pitch_lag[i >> 1],
02187                            p->subframe[i], p->cur_rate);
02188         sub_acb_contrib(residual, impulse_resp, in);
02189 
02190         fcb_search(p, impulse_resp, in, i);
02191 
02192         /* Reconstruct the excitation */
02193         gen_acb_excitation(impulse_resp, p->prev_excitation, p->pitch_lag[i >> 1],
02194                            p->subframe[i], Rate6k3);
02195 
02196         memmove(p->prev_excitation, p->prev_excitation + SUBFRAME_LEN,
02197                sizeof(int16_t) * (PITCH_MAX - SUBFRAME_LEN));
02198         for (j = 0; j < SUBFRAME_LEN; j++)
02199             in[j] = av_clip_int16((in[j] << 1) + impulse_resp[j]);
02200         memcpy(p->prev_excitation + PITCH_MAX - SUBFRAME_LEN, in,
02201                sizeof(int16_t) * SUBFRAME_LEN);
02202 
02203         /* Update filter memories */
02204         synth_percept_filter(qnt_lpc + offset, weighted_lpc + (offset << 1),
02205                              p->perf_fir_mem, p->perf_iir_mem,
02206                              in, vector + PITCH_MAX, 0);
02207         memmove(p->harmonic_mem, p->harmonic_mem + SUBFRAME_LEN,
02208                 sizeof(int16_t) * (PITCH_MAX - SUBFRAME_LEN));
02209         memcpy(p->harmonic_mem + PITCH_MAX - SUBFRAME_LEN, vector + PITCH_MAX,
02210                sizeof(int16_t) * SUBFRAME_LEN);
02211 
02212         in += SUBFRAME_LEN;
02213         offset += LPC_ORDER;
02214     }
02215 
02216     return pack_bitstream(p, buf, buf_size);
02217 }
02218 
02219 AVCodec ff_g723_1_encoder = {
02220     .name           = "g723_1",
02221     .type           = AVMEDIA_TYPE_AUDIO,
02222     .id             = CODEC_ID_G723_1,
02223     .priv_data_size = sizeof(G723_1_Context),
02224     .init           = g723_1_encode_init,
02225     .encode         = g723_1_encode_frame,
02226     .long_name      = NULL_IF_CONFIG_SMALL("G.723.1"),
02227     .sample_fmts    = (const enum SampleFormat[]){AV_SAMPLE_FMT_S16,
02228                                                   AV_SAMPLE_FMT_NONE},
02229 };
02230 #endif