/src/ffmpeg/libavcodec/wma_common.c
Line | Count | Source |
1 | | /* |
2 | | * common code shared by all WMA variants |
3 | | * |
4 | | * This file is part of FFmpeg. |
5 | | * |
6 | | * FFmpeg is free software; you can redistribute it and/or |
7 | | * modify it under the terms of the GNU Lesser General Public |
8 | | * License as published by the Free Software Foundation; either |
9 | | * version 2.1 of the License, or (at your option) any later version. |
10 | | * |
11 | | * FFmpeg is distributed in the hope that it will be useful, |
12 | | * but WITHOUT ANY WARRANTY; without even the implied warranty of |
13 | | * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU |
14 | | * Lesser General Public License for more details. |
15 | | * |
16 | | * You should have received a copy of the GNU Lesser General Public |
17 | | * License along with FFmpeg; if not, write to the Free Software |
18 | | * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA |
19 | | */ |
20 | | |
21 | | #include "libavutil/attributes.h" |
22 | | |
23 | | #include "wma_common.h" |
24 | | |
25 | | /** |
26 | | *@brief Get the samples per frame for this stream. |
27 | | *@param sample_rate output sample_rate |
28 | | *@param version wma version |
29 | | *@param decode_flags codec compression features |
30 | | *@return log2 of the number of output samples per frame |
31 | | */ |
32 | | av_cold int ff_wma_get_frame_len_bits(int sample_rate, int version, |
33 | | unsigned int decode_flags) |
34 | 4.53k | { |
35 | 4.53k | int frame_len_bits; |
36 | | |
37 | 4.53k | if (sample_rate <= 16000) |
38 | 1.45k | frame_len_bits = 9; |
39 | 3.07k | else if (sample_rate <= 22050 || (sample_rate <= 32000 && version == 1)) |
40 | 490 | frame_len_bits = 10; |
41 | 2.58k | else if (sample_rate <= 48000 || version < 3) |
42 | 961 | frame_len_bits = 11; |
43 | 1.62k | else if (sample_rate <= 96000) |
44 | 206 | frame_len_bits = 12; |
45 | 1.41k | else |
46 | 1.41k | frame_len_bits = 13; |
47 | | |
48 | 4.53k | if (version == 3) { |
49 | 2.38k | int tmp = decode_flags & 0x6; |
50 | 2.38k | if (tmp == 0x2) |
51 | 85 | ++frame_len_bits; |
52 | 2.30k | else if (tmp == 0x4) |
53 | 748 | --frame_len_bits; |
54 | 1.55k | else if (tmp == 0x6) |
55 | 451 | frame_len_bits -= 2; |
56 | 2.38k | } |
57 | | |
58 | 4.53k | return frame_len_bits; |
59 | 4.53k | } |