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atrac1data.h
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1 /*
2  * ATRAC 1 compatible decoder data
3  * Copyright (c) 2009 Maxim Poliakovski
4  * Copyright (c) 2009 Benjamin Larsson
5  *
6  * This file is part of FFmpeg.
7  *
8  * FFmpeg is free software; you can redistribute it and/or
9  * modify it under the terms of the GNU Lesser General Public
10  * License as published by the Free Software Foundation; either
11  * version 2.1 of the License, or (at your option) any later version.
12  *
13  * FFmpeg is distributed in the hope that it will be useful,
14  * but WITHOUT ANY WARRANTY; without even the implied warranty of
15  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
16  * Lesser General Public License for more details.
17  *
18  * You should have received a copy of the GNU Lesser General Public
19  * License along with FFmpeg; if not, write to the Free Software
20  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
21  */
22 
23 /**
24  * @file
25  * ATRAC1 compatible decoder data
26  */
27 
28 #ifndef AVCODEC_ATRAC1DATA_H
29 #define AVCODEC_ATRAC1DATA_H
30 
31 #include <stdint.h>
32 
33 static const uint8_t bfu_amount_tab1[8] = {20, 28, 32, 36, 40, 44, 48, 52};
34 static const uint8_t bfu_amount_tab2[4] = { 0, 112, 176, 208};
35 static const uint8_t bfu_amount_tab3[8] = { 0, 24, 36, 48, 72, 108, 132, 156};
36 
37 /** number of BFUs in each QMF band */
38 static const uint8_t bfu_bands_t[4] = {0, 20, 36, 52};
39 
40 /** number of spectral lines in each BFU
41  * block floating unit = group of spectral frequencies having the
42  * same quantization parameters like word length and scale factor
43  */
44 static const uint8_t specs_per_bfu[52] = {
45  8, 8, 8, 8, 4, 4, 4, 4, 8, 8, 8, 8, 6, 6, 6, 6, 6, 6, 6, 6, // low band
46  6, 6, 6, 6, 7, 7, 7, 7, 9, 9, 9, 9, 10, 10, 10, 10, // middle band
47  12, 12, 12, 12, 12, 12, 12, 12, 20, 20, 20, 20, 20, 20, 20, 20 // high band
48 };
49 
50 /** start position of each BFU in the MDCT spectrum for the long mode */
51 static const uint16_t bfu_start_long[52] = {
52  0, 8, 16, 24, 32, 36, 40, 44, 48, 56, 64, 72, 80, 86, 92, 98, 104, 110, 116, 122,
53  128, 134, 140, 146, 152, 159, 166, 173, 180, 189, 198, 207, 216, 226, 236, 246,
54  256, 268, 280, 292, 304, 316, 328, 340, 352, 372, 392, 412, 432, 452, 472, 492,
55 };
56 
57 /** start position of each BFU in the MDCT spectrum for the short mode */
58 static const uint16_t bfu_start_short[52] = {
59  0, 32, 64, 96, 8, 40, 72, 104, 12, 44, 76, 108, 20, 52, 84, 116, 26, 58, 90, 122,
60  128, 160, 192, 224, 134, 166, 198, 230, 141, 173, 205, 237, 150, 182, 214, 246,
61  256, 288, 320, 352, 384, 416, 448, 480, 268, 300, 332, 364, 396, 428, 460, 492
62 };
63 
64 #endif /* AVCODEC_ATRAC1DATA_H */