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mpegaudio.c
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1 /*
2  * MPEG Audio common code
3  * Copyright (c) 2001, 2002 Fabrice Bellard
4  *
5  * This file is part of FFmpeg.
6  *
7  * FFmpeg is free software; you can redistribute it and/or
8  * modify it under the terms of the GNU Lesser General Public
9  * License as published by the Free Software Foundation; either
10  * version 2.1 of the License, or (at your option) any later version.
11  *
12  * FFmpeg is distributed in the hope that it will be useful,
13  * but WITHOUT ANY WARRANTY; without even the implied warranty of
14  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
15  * Lesser General Public License for more details.
16  *
17  * You should have received a copy of the GNU Lesser General Public
18  * License along with FFmpeg; if not, write to the Free Software
19  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
20  */
21 
22 /**
23  * @file
24  * MPEG Audio common code.
25  */
26 
27 #include "mpegaudio.h"
28 
29 
30 /* bitrate is in kb/s */
31 int ff_mpa_l2_select_table(int bitrate, int nb_channels, int freq, int lsf)
32 {
33  int ch_bitrate, table;
34 
35  ch_bitrate = bitrate / nb_channels;
36  if (!lsf) {
37  if ((freq == 48000 && ch_bitrate >= 56) ||
38  (ch_bitrate >= 56 && ch_bitrate <= 80))
39  table = 0;
40  else if (freq != 48000 && ch_bitrate >= 96)
41  table = 1;
42  else if (freq != 32000 && ch_bitrate <= 48)
43  table = 2;
44  else
45  table = 3;
46  } else {
47  table = 4;
48  }
49  return table;
50 }
static const uint16_t table[]
Definition: prosumer.c:205
int64_t bitrate
Definition: h264_levels.c:89
mpeg audio declarations for both encoder and decoder.
int ff_mpa_l2_select_table(int bitrate, int nb_channels, int freq, int lsf)
Definition: mpegaudio.c:31
int nb_channels