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 */
32av_cold int ff_wma_get_frame_len_bits(int sample_rate, int version,
33                                      unsigned int decode_flags)
34{
35    int frame_len_bits;
36
37    if (sample_rate <= 16000)
38        frame_len_bits = 9;
39    else if (sample_rate <= 22050 || (sample_rate <= 32000 && version == 1))
40        frame_len_bits = 10;
41    else if (sample_rate <= 48000 || version < 3)
42        frame_len_bits = 11;
43    else if (sample_rate <= 96000)
44        frame_len_bits = 12;
45    else
46        frame_len_bits = 13;
47
48    if (version == 3) {
49        int tmp = decode_flags & 0x6;
50        if (tmp == 0x2)
51            ++frame_len_bits;
52        else if (tmp == 0x4)
53            --frame_len_bits;
54        else if (tmp == 0x6)
55            frame_len_bits -= 2;
56    }
57
58    return frame_len_bits;
59}
60