MP3: Support decode mp3 by FFmpeg natively. (#296) (#3340)

2025-03-09 15:49:59 +00:00 · 2022-12-26 13:23:39 +08:00 · 2022-12-26 13:23:39 +08:00 · 1c5788c638
commit 1c5788c638
parent fe3502e6ad
29 changed files with 6001 additions and 0 deletions
--- a/trunk/3rdparty/ffmpeg-4-fit/libavcodec/mpegaudiotab.h
+++ b/trunk/3rdparty/ffmpeg-4-fit/libavcodec/mpegaudiotab.h
@ -0,0 +1,102 @@
+/*
+ * mpeg audio layer 2 tables. Most of them come from the mpeg audio
+ * specification.
+ *
+ * Copyright (c) 2000, 2001 Fabrice Bellard
+ *
+ * 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
+ */
+
+/**
+ * @file
+ * mpeg audio layer 2 tables.
+ * Most of them come from the mpeg audio specification.
+ */
+
+#ifndef AVCODEC_MPEGAUDIOTAB_H
+#define AVCODEC_MPEGAUDIOTAB_H
+
+#include <stdint.h>
+#include "mpegaudio.h"
+
+static const int costab32[30] = {
+    FIX(0.54119610014619701222),
+    FIX(1.3065629648763763537),
+
+    FIX(0.50979557910415917998),
+    FIX(2.5629154477415054814),
+    FIX(0.89997622313641556513),
+    FIX(0.60134488693504528634),
+
+    FIX(0.5024192861881556782),
+    FIX(5.1011486186891552563),
+    FIX(0.78815462345125020249),
+    FIX(0.64682178335999007679),
+    FIX(0.56694403481635768927),
+    FIX(1.0606776859903470633),
+    FIX(1.7224470982383341955),
+    FIX(0.52249861493968885462),
+
+    FIX(10.19000812354803287),
+    FIX(0.674808341455005678),
+    FIX(1.1694399334328846596),
+    FIX(0.53104259108978413284),
+    FIX(2.0577810099534108446),
+    FIX(0.58293496820613388554),
+    FIX(0.83934964541552681272),
+    FIX(0.50547095989754364798),
+    FIX(3.4076084184687189804),
+    FIX(0.62250412303566482475),
+    FIX(0.97256823786196078263),
+    FIX(0.51544730992262455249),
+    FIX(1.4841646163141661852),
+    FIX(0.5531038960344445421),
+    FIX(0.74453627100229857749),
+    FIX(0.5006029982351962726),
+};
+
+static const int bitinv32[32] = {
+    0,  16,  8, 24,  4,  20,  12,  28,
+    2,  18, 10, 26,  6,  22,  14,  30,
+    1,  17,  9, 25,  5,  21,  13,  29,
+    3,  19, 11, 27,  7,  23,  15,  31
+};
+
+
+/* signal to noise ratio of each quantification step (could be
+   computed from quant_steps[]). The values are dB multiplied by 10
+*/
+static const unsigned short quant_snr[17] = {
+     70, 110, 160, 208,
+    253, 316, 378, 439,
+    499, 559, 620, 680,
+    740, 800, 861, 920,
+    980
+};
+
+/* fixed psycho acoustic model. Values of SNR taken from the 'toolame'
+   project */
+static const float fixed_smr[SBLIMIT] =  {
+    30, 17, 16, 10, 3, 12, 8, 2.5,
+    5, 5, 6, 6, 5, 6, 10, 6,
+    -4, -10, -21, -30, -42, -55, -68, -75,
+    -75, -75, -75, -75, -91, -107, -110, -108
+};
+
+static const unsigned char nb_scale_factors[4] = { 3, 2, 1, 2 };
+
+#endif /* AVCODEC_MPEGAUDIOTAB_H */