SIPR16k decoder

Originally committed as revision 21234 to svn://svn.ffmpeg.org/ffmpeg/trunk

1 files changed, 274 insertions, 0 deletions

diff --git a/libavcodec/sipr16k.c b/libavcodec/sipr16k.c
new file mode 100644
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+++ b/libavcodec/sipr16k.c
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+/*
+ * SIPR decoder for the 16k mode
+ *
+ * Copyright (c) 2008 Vladimir Voroshilov
+ * Copyright (c) 2009 Vitor Sessak
+ *
+ * This file is part of FFmpeg.
+ *
+ * FFmpeg is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU Lesser General Public
+ * License as published by the Free Software Foundation; either
+ * version 2.1 of the License, or (at your option) any later version.
+ *
+ * FFmpeg is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public
+ * License along with FFmpeg; if not, write to the Free Software
+ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
+ */
+
+#include <math.h>
+
+#include "sipr.h"
+#include "libavutil/mathematics.h"
+#include "lsp.h"
+#include "celp_math.h"
+#include "acelp_vectors.h"
+#include "acelp_pitch_delay.h"
+#include "acelp_filters.h"
+#include "celp_filters.h"
+
+#include "sipr16kdata.h"
+
+/**
+ * Convert an lsf vector into an lsp vector.
+ *
+ * @param lsf               input lsf vector
+ * @param lsp               output lsp vector
+ */
+static void lsf2lsp(const float *lsf, double *lsp)
+{
+    int i;
+
+    for (i = 0; i < LP_FILTER_ORDER_16k; i++)
+        lsp[i] = cosf(lsf[i]);
+}
+
+static void dequant(float *out, const int *idx, const float *cbs[])
+{
+    int i;
+
+    for (i = 0; i < 4; i++)
+        memcpy(out + 3*i, cbs[i] + 3*idx[i], 3*sizeof(float));
+
+    memcpy(out + 12, cbs[4] + 4*idx[4], 4*sizeof(float));
+}
+
+static void lsf_decode_fp_16k(float* lsf_history, float* isp_new,
+                              const int* parm, int ma_pred)
+{
+    int i;
+    float isp_q[LP_FILTER_ORDER_16k];
+
+    dequant(isp_q, parm, lsf_codebooks_16k);
+
+    for (i = 0; i < LP_FILTER_ORDER_16k; i++) {
+        isp_new[i] = (1 - qu[ma_pred]) * isp_q[i]
+                    +     qu[ma_pred]  * lsf_history[i]
+                    + mean_lsf_16k[i];
+    }
+
+    memcpy(lsf_history, isp_q, LP_FILTER_ORDER_16k * sizeof(float));
+}
+
+static int dec_delay3_1st(int index)
+{
+    if (index < 390) {
+        return index + 88;
+    } else
+        return 3 * index - 690;
+}
+
+static int dec_delay3_2nd(int index, int pit_min, int pit_max,
+                          int pitch_lag_prev)
+{
+    if (index < 62) {
+        int pitch_delay_min = av_clip(pitch_lag_prev - 10,
+                                      pit_min, pit_max - 19);
+        return 3 * pitch_delay_min + index - 2;
+    } else
+        return 3 * pitch_lag_prev;
+}
+
+static void postfilter(float* synth, float* iir_mem, float* filt_mem[2],
+                       float* mem_preemph)
+{
+    float buf[30 + LP_FILTER_ORDER_16k];
+    float *tmpbuf = buf + LP_FILTER_ORDER_16k;
+    float s;
+    int i;
+
+    for (i = 0; i < LP_FILTER_ORDER_16k; i++)
+        filt_mem[0][i] = iir_mem[i] * ff_pow_0_5[i];
+
+    memcpy(tmpbuf - LP_FILTER_ORDER_16k, mem_preemph,
+           LP_FILTER_ORDER_16k*sizeof(*buf));
+
+    ff_celp_lp_synthesis_filterf(tmpbuf, filt_mem[1], synth, 30,
+                                 LP_FILTER_ORDER_16k);
+
+    memcpy(synth - LP_FILTER_ORDER_16k, mem_preemph,
+           LP_FILTER_ORDER_16k * sizeof(*synth));
+
+    ff_celp_lp_synthesis_filterf(synth, filt_mem[0], synth, 2*L_SUBFR_16k,
+                                 LP_FILTER_ORDER_16k);
+
+    memcpy(mem_preemph, synth + 2*L_SUBFR_16k - LP_FILTER_ORDER_16k,
+           LP_FILTER_ORDER_16k * sizeof(*synth));
+
+    FFSWAP(float *, filt_mem[0], filt_mem[1]);
+    for (i = 0, s = 0; i < 30; i++, s += 1.0/30)
+        synth[i] = tmpbuf[i] + s * (synth[i] - tmpbuf[i]);
+}
+
+/**
+ * Floating point version of ff_acelp_lp_decode().
+ */
+static void acelp_lp_decodef(float *lp_1st, float *lp_2nd,
+                             const double *lsp_2nd, const double *lsp_prev)
+{
+    double lsp_1st[LP_FILTER_ORDER_16k];
+    int i;
+
+    /* LSP values for first subframe (3.2.5 of G.729, Equation 24) */
+    for (i = 0; i < LP_FILTER_ORDER_16k; i++)
+        lsp_1st[i] = (lsp_2nd[i] + lsp_prev[i]) * 0.5;
+
+    ff_acelp_lspd2lpc(lsp_1st, lp_1st, LP_FILTER_ORDER_16k >> 1);
+
+    /* LSP values for second subframe (3.2.5 of G.729) */
+    ff_acelp_lspd2lpc(lsp_2nd, lp_2nd, LP_FILTER_ORDER_16k >> 1);
+}
+
+/**
+ * Floating point version of ff_acelp_decode_gain_code().
+ */
+static float acelp_decode_gain_codef(float gain_corr_factor, const float *fc_v,
+                                     float mr_energy, const float *quant_energy,
+                                     const float *ma_prediction_coeff,
+                                     int subframe_size, int ma_pred_order)
+{
+    mr_energy +=
+        ff_dot_productf(quant_energy, ma_prediction_coeff, ma_pred_order);
+
+    mr_energy = gain_corr_factor * exp(M_LN10 / 20. * mr_energy) /
+        sqrt((0.01 + ff_dot_productf(fc_v, fc_v, subframe_size)));
+    return mr_energy;
+}
+
+#define DIVIDE_BY_3(x) ((x) * 10923 >> 15)
+
+void ff_sipr_decode_frame_16k(SiprContext *ctx, SiprParameters *params,
+                              float *out_data)
+{
+    int frame_size = SUBFRAME_COUNT_16k * L_SUBFR_16k;
+    float *synth = ctx->synth_buf + LP_FILTER_ORDER_16k;
+    float lsf_new[LP_FILTER_ORDER_16k];
+    double lsp_new[LP_FILTER_ORDER_16k];
+    float Az[2][LP_FILTER_ORDER_16k];
+    float fixed_vector[L_SUBFR_16k];
+    float pitch_fac, gain_code;
+
+    int i;
+    int pitch_delay_3x;
+
+    float *excitation = ctx->excitation + 292;
+
+    lsf_decode_fp_16k(ctx->lsf_history, lsf_new, params->vq_indexes,
+                      params->ma_pred_switch);
+
+    ff_set_min_dist_lsf(lsf_new, LSFQ_DIFF_MIN / 2, LP_FILTER_ORDER_16k);
+
+    lsf2lsp(lsf_new, lsp_new);
+
+    acelp_lp_decodef(Az[0], Az[1], lsp_new, ctx->lsp_history_16k);
+
+    memcpy(ctx->lsp_history_16k, lsp_new, LP_FILTER_ORDER_16k * sizeof(double));
+
+    memcpy(synth - LP_FILTER_ORDER_16k, ctx->synth,
+           LP_FILTER_ORDER_16k * sizeof(*synth));
+
+    for (i = 0; i < SUBFRAME_COUNT_16k; i++) {
+        int i_subfr = i * L_SUBFR_16k;
+        AMRFixed f;
+        float gain_corr_factor;
+        int pitch_delay_int;
+        int pitch_delay_frac;
+
+        if (!i) {
+            pitch_delay_3x = dec_delay3_1st(params->pitch_delay[i]);
+        } else
+            pitch_delay_3x = dec_delay3_2nd(params->pitch_delay[i],
+                                            PITCH_MIN, PITCH_MAX,
+                                            ctx->pitch_lag_prev);
+
+        pitch_fac = gain_pitch_cb_16k[params->gp_index[i]];
+        f.pitch_fac = FFMIN(pitch_fac, 1.0);
+        f.pitch_lag = DIVIDE_BY_3(pitch_delay_3x+1);
+        ctx->pitch_lag_prev = f.pitch_lag;
+
+        pitch_delay_int  = DIVIDE_BY_3(pitch_delay_3x + 2);
+        pitch_delay_frac = pitch_delay_3x + 2 - 3*pitch_delay_int;
+
+        ff_acelp_interpolatef(&excitation[i_subfr],
+                              &excitation[i_subfr] - pitch_delay_int + 1,
+                              sinc_win, 3, pitch_delay_frac + 1,
+                              LP_FILTER_ORDER, L_SUBFR_16k);
+
+
+        memset(fixed_vector, 0, sizeof(fixed_vector));
+
+        ff_decode_10_pulses_35bits(params->fc_indexes[i], &f,
+                                   ff_fc_4pulses_8bits_tracks_13, 5, 4);
+
+        ff_set_fixed_vector(fixed_vector, &f, 1.0, L_SUBFR_16k);
+
+        gain_corr_factor = gain_cb_16k[params->gc_index[i]];
+        gain_code = gain_corr_factor *
+            acelp_decode_gain_codef(sqrt(L_SUBFR_16k), fixed_vector,
+                                    19.0 - 15.0/(0.05*M_LN10/M_LN2),
+                                    pred_16k, ctx->energy_history,
+                                    L_SUBFR_16k, 2);
+
+        ctx->energy_history[1] = ctx->energy_history[0];
+        ctx->energy_history[0] = 20.0 * log10f(gain_corr_factor);
+
+        ff_weighted_vector_sumf(&excitation[i_subfr], &excitation[i_subfr],
+                                fixed_vector, pitch_fac,
+                                gain_code, L_SUBFR_16k);
+
+        ff_celp_lp_synthesis_filterf(synth + i_subfr, Az[i],
+                                     &excitation[i_subfr], L_SUBFR_16k,
+                                     LP_FILTER_ORDER_16k);
+
+    }
+    memcpy(ctx->synth, synth + frame_size - LP_FILTER_ORDER_16k,
+           LP_FILTER_ORDER_16k * sizeof(*synth));
+
+    memmove(ctx->excitation, ctx->excitation + 2 * L_SUBFR_16k,
+            (L_INTERPOL+PITCH_MAX) * sizeof(float));
+
+    postfilter(synth, ctx->iir_mem, ctx->filt_mem, ctx->mem_preemph);
+
+    memcpy(ctx->iir_mem, Az[1], LP_FILTER_ORDER_16k * sizeof(float));
+
+    ctx->dsp.vector_clipf(out_data, synth, -1, 32767./(1<<15), frame_size);
+
+}
+
+void ff_sipr_init_16k(SiprContext *ctx)
+{
+    int i;
+
+    for (i = 0; i < LP_FILTER_ORDER_16k; i++)
+        ctx->lsp_history_16k[i] = cos((i + 1) * M_PI/(LP_FILTER_ORDER_16k + 1));
+
+    ctx->filt_mem[0] = ctx->filt_buf[0];
+    ctx->filt_mem[1] = ctx->filt_buf[1];
+
+    ctx->pitch_lag_prev = 180;
+}