blob: cba52992ef3130fb09c92889002e7f056ac3a5b7
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 | } |
51 |