merge FAAD2 - the GPL AAC decoder library.

xine_decoder.c is working, but demux_qt must send some needed
initialization data. currently it's hardcoded to play my test stream, so
it's not usable yet.

CVS patchset: 2267
CVS date: 2002/07/14 23:43:01

1 files changed, 180 insertions, 0 deletions

diff --git a/src/libfaad/ic_predict.c b/src/libfaad/ic_predict.c
new file mode 100644
index 000000000..28f5a2d0a
--- /dev/null
+++ b/src/libfaad/ic_predict.c
@@ -0,0 +1,180 @@
+/*
+** FAAD - Freeware Advanced Audio Decoder
+** Copyright (C) 2002 M. Bakker
+**  
+** This program is free software; you can redistribute it and/or modify
+** it under the terms of the GNU General Public License as published by
+** the Free Software Foundation; either version 2 of the License, or
+** (at your option) any later version.
+** 
+** This program 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 General Public License for more details.
+** 
+** You should have received a copy of the GNU General Public License
+** along with this program; if not, write to the Free Software 
+** Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
+**
+** $Id: ic_predict.c,v 1.1 2002/07/14 23:43:01 miguelfreitas Exp $
+**/
+
+#include "common.h"
+
+#ifdef MAIN_DEC
+
+#include "syntax.h"
+#include "ic_predict.h"
+#include "pns.h"
+
+static void flt_round_inf(real_t *pf)
+{
+    int32_t flg;
+    uint32_t tmp;
+    real_t *pt = (real_t *)&tmp;
+
+    *pt = *pf;
+    flg = tmp & (uint32_t)0x00008000;
+    tmp &= (uint32_t)0xffff0000;
+    *pf = *pt;
+
+    /* round 1/2 lsb toward infinity */
+    if (flg)
+    {
+        tmp &= (uint32_t)0xff800000; /* extract exponent and sign */
+        tmp |= (uint32_t)0x00010000; /* insert 1 lsb */
+        *pf += *pt;                  /* add 1 lsb and elided one */
+        tmp &= (uint32_t)0xff800000; /* extract exponent and sign */
+        *pf -= *pt;                  /* subtract elided one */
+    }
+}
+
+static void ic_predict(pred_state *state, real_t input, real_t *output, uint8_t pred)
+{
+    real_t dr1, predictedvalue;
+    real_t e0, e1;
+    real_t k1, k2;
+
+    real_t *r;
+    real_t *KOR;
+    real_t *VAR;
+
+    r   = state->r;   /* delay elements */
+    KOR = state->KOR; /* correlations */
+    VAR = state->VAR; /* variances */
+
+    k1 = KOR[0]/VAR[0]*B;
+
+    if (pred)
+    {
+        /* only needed for the actual predicted value, k1 is always needed */
+        k2 = KOR[1]/VAR[1]*B;
+
+        predictedvalue = MUL(k1, r[0]) + MUL(k2, r[1]);
+        flt_round_inf(&predictedvalue);
+
+        *output = input + predictedvalue;
+    } else {
+        *output = input;
+    }
+
+    /* calculate new state data */
+    e0 = *output;
+    e1 = e0 - MUL(k1, r[0]);
+
+    dr1 = k1 * e0;
+
+    VAR[0] = MUL(ALPHA, VAR[0]) + (0.5f) * (MUL(r[0], r[0]) + MUL(e0, e0));
+    KOR[0] = MUL(ALPHA, KOR[0]) + MUL(r[0], e0);
+    VAR[1] = MUL(ALPHA, VAR[1]) + (0.5f) * (MUL(r[1], r[1]) + MUL(e1, e1));
+    KOR[1] = MUL(ALPHA, KOR[1]) + MUL(r[1], e1);
+
+    r[1] = MUL(A, (r[0]-dr1));
+    r[0] = MUL(A, e0);
+}
+
+static void reset_pred_state(pred_state *state)
+{
+    state->r[0]   = 0.0f;
+    state->r[1]   = 0.0f;
+    state->KOR[0] = 0.0f;
+    state->KOR[1] = 0.0f;
+    state->VAR[0] = 1.0f;
+    state->VAR[1] = 1.0f;
+}
+
+void pns_reset_pred_state(ic_stream *ics, pred_state *state)
+{
+    uint8_t sfb, g, b;
+    uint16_t i, offs, offs2;
+
+    /* prediction only for long blocks */
+    if (ics->window_sequence == EIGHT_SHORT_SEQUENCE)
+        return;
+
+    for (g = 0; g < ics->num_window_groups; g++)
+    {
+        for (b = 0; b < ics->window_group_length[g]; b++)
+        {
+            for (sfb = 0; sfb < ics->max_sfb; sfb++)
+            {
+                if (is_noise(ics, g, sfb))
+                {
+                    offs = ics->swb_offset[sfb];
+                    offs2 = ics->swb_offset[sfb+1];
+
+                    for (i = offs; i < offs2; i++)
+                        reset_pred_state(&state[i]);
+                }
+            }
+        }
+    }
+}
+
+void reset_all_predictors(pred_state *state, uint16_t frame_len)
+{
+    uint16_t i;
+
+    for (i = 0; i < frame_len; i++)
+        reset_pred_state(&state[i]);
+}
+
+/* intra channel prediction */
+void ic_prediction(ic_stream *ics, real_t *spec, pred_state *state,
+                   uint16_t frame_len)
+{
+    uint8_t sfb;
+    uint16_t bin;
+
+    if (ics->window_sequence == EIGHT_SHORT_SEQUENCE)
+    {
+        reset_all_predictors(state, frame_len);
+    } else {
+        for (sfb = 0; sfb < ics->pred.limit; sfb++)
+        {
+            uint16_t low  = ics->swb_offset[sfb];
+            uint16_t high = ics->swb_offset[sfb+1];
+
+            for (bin = low; bin < high; bin++)
+            {
+                ic_predict(&state[bin], spec[bin], &spec[bin],
+                    (ics->predictor_data_present &&
+                    ics->pred.prediction_used[sfb]));
+            }
+        }
+
+        if (ics->predictor_data_present)
+        {
+            if (ics->pred.predictor_reset)
+            {
+                for (bin = ics->pred.predictor_reset_group_number - 1;
+                     bin < frame_len; bin += 30)
+                {
+                    reset_pred_state(&state[bin]);
+                }
+            }
+        }
+    }
+}
+
+#endif