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authorarpi <arpi@b3059339-0415-0410-9bf9-f77b7e298cf2>2003-08-30 22:30:28 +0000
committerarpi <arpi@b3059339-0415-0410-9bf9-f77b7e298cf2>2003-08-30 22:30:28 +0000
commit32063c433915b8dddd143a951ad90ae901ac1b38 (patch)
tree88aaee983b0885b5bb22d870476f7afdaa8a7010 /libfaad2/lt_predict.c
parent264633eec589baddfdcd79dde08fd7f1f47fba51 (diff)
downloadmpv-32063c433915b8dddd143a951ad90ae901ac1b38.tar.bz2
mpv-32063c433915b8dddd143a951ad90ae901ac1b38.tar.xz
libfaad2 v2.0rc1 imported
git-svn-id: svn://svn.mplayerhq.hu/mplayer/trunk@10726 b3059339-0415-0410-9bf9-f77b7e298cf2
Diffstat (limited to 'libfaad2/lt_predict.c')
-rw-r--r--libfaad2/lt_predict.c146
1 files changed, 146 insertions, 0 deletions
diff --git a/libfaad2/lt_predict.c b/libfaad2/lt_predict.c
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+/*
+** FAAD2 - Freeware Advanced Audio (AAC) Decoder including SBR decoding
+** Copyright (C) 2003 M. Bakker, Ahead Software AG, http://www.nero.com
+**
+** 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.
+**
+** Any non-GPL usage of this software or parts of this software is strictly
+** forbidden.
+**
+** Commercial non-GPL licensing of this software is possible.
+** For more info contact Ahead Software through Mpeg4AAClicense@nero.com.
+**
+** $Id: lt_predict.c,v 1.11 2003/07/29 08:20:12 menno Exp $
+**/
+
+#include "common.h"
+#include "structs.h"
+
+#ifdef LTP_DEC
+
+#include <stdlib.h>
+#include "syntax.h"
+#include "lt_predict.h"
+#include "filtbank.h"
+#include "tns.h"
+
+static real_t codebook[8] =
+{
+ COEF_CONST(0.570829),
+ COEF_CONST(0.696616),
+ COEF_CONST(0.813004),
+ COEF_CONST(0.911304),
+ COEF_CONST(0.984900),
+ COEF_CONST(1.067894),
+ COEF_CONST(1.194601),
+ COEF_CONST(1.369533)
+};
+
+void lt_prediction(ic_stream *ics, ltp_info *ltp, real_t *spec,
+ real_t *lt_pred_stat, fb_info *fb, uint8_t win_shape,
+ uint8_t win_shape_prev, uint8_t sr_index,
+ uint8_t object_type, uint16_t frame_len)
+{
+ uint8_t sfb;
+ uint16_t bin, i, num_samples;
+ real_t *x_est;
+ real_t *X_est;
+
+ if (ics->window_sequence != EIGHT_SHORT_SEQUENCE)
+ {
+ if (ltp->data_present)
+ {
+ num_samples = frame_len << 1;
+
+ x_est = (real_t*)malloc(num_samples*sizeof(real_t));
+ X_est = (real_t*)malloc(num_samples*sizeof(real_t));
+
+ for(i = 0; i < num_samples; i++)
+ {
+ /* The extra lookback M (N/2 for LD, 0 for LTP) is handled
+ in the buffer updating */
+ x_est[i] = MUL_R_C(lt_pred_stat[num_samples + i - ltp->lag],
+ codebook[ltp->coef]);
+ }
+
+ filter_bank_ltp(fb, ics->window_sequence, win_shape, win_shape_prev,
+ x_est, X_est, object_type, frame_len);
+
+ tns_encode_frame(ics, &(ics->tns), sr_index, object_type, X_est,
+ frame_len);
+
+ for (sfb = 0; sfb < ltp->last_band; sfb++)
+ {
+ if (ltp->long_used[sfb])
+ {
+ uint16_t low = ics->swb_offset[sfb];
+ uint16_t high = ics->swb_offset[sfb+1];
+
+ for (bin = low; bin < high; bin++)
+ {
+ spec[bin] += X_est[bin];
+ }
+ }
+ }
+
+ free(x_est);
+ free(X_est);
+ }
+ }
+}
+
+void lt_update_state(real_t *lt_pred_stat, real_t *time, real_t *overlap,
+ uint16_t frame_len, uint8_t object_type)
+{
+ uint16_t i;
+
+ /*
+ * The reference point for index i and the content of the buffer
+ * lt_pred_stat are arranged so that lt_pred_stat(0 ... N/2 - 1) contains the
+ * last aliased half window from the IMDCT, and lt_pred_stat(N/2 ... N-1)
+ * is always all zeros. The rest of lt_pred_stat (i<0) contains the previous
+ * fully reconstructed time domain samples, i.e., output of the decoder.
+ *
+ * These values are shifted up by N*2 to avoid (i<0)
+ *
+ * For the LD object type an extra 512 samples lookback is accomodated here.
+ */
+#ifdef LD_DEC
+ if (object_type == LD)
+ {
+ for (i = 0; i < frame_len; i++)
+ {
+ lt_pred_stat[i] /* extra 512 */ = lt_pred_stat[i + frame_len];
+ lt_pred_stat[frame_len + i] = lt_pred_stat[i + (frame_len * 2)];
+ lt_pred_stat[(frame_len * 2) + i] = time[i];
+ lt_pred_stat[(frame_len * 3) + i] = overlap[i];
+ }
+ } else {
+#endif
+ for (i = 0; i < frame_len; i++)
+ {
+ lt_pred_stat[i] = lt_pred_stat[i + frame_len];
+ lt_pred_stat[frame_len + i] = time[i];
+ lt_pred_stat[(frame_len * 2) + i] = overlap[i];
+#if 0 /* set to zero once upon initialisation */
+ lt_pred_stat[(frame_len * 3) + i] = 0;
+#endif
+ }
+#ifdef LD_DEC
+ }
+#endif
+}
+
+#endif