Mercurial > SDL_sound_CoreAudio
comparison decoders/mpglib/tabinit.c @ 261:9b6e82f7c853
Initial add.
author | Ryan C. Gordon <icculus@icculus.org> |
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date | Thu, 21 Feb 2002 19:46:09 +0000 |
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260:44a4730a1e6f | 261:9b6e82f7c853 |
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1 | |
2 #include <stdlib.h> | |
3 | |
4 #include "mpg123_sdlsound.h" | |
5 | |
6 real decwin[512+32]; | |
7 static real cos64[16],cos32[8],cos16[4],cos8[2],cos4[1]; | |
8 real *pnts[] = { cos64,cos32,cos16,cos8,cos4 }; | |
9 | |
10 #if 0 | |
11 static unsigned char *conv16to8_buf = NULL; | |
12 unsigned char *conv16to8; | |
13 #endif | |
14 | |
15 static long intwinbase[] = { | |
16 0, -1, -1, -1, -1, -1, -1, -2, -2, -2, | |
17 -2, -3, -3, -4, -4, -5, -5, -6, -7, -7, | |
18 -8, -9, -10, -11, -13, -14, -16, -17, -19, -21, | |
19 -24, -26, -29, -31, -35, -38, -41, -45, -49, -53, | |
20 -58, -63, -68, -73, -79, -85, -91, -97, -104, -111, | |
21 -117, -125, -132, -139, -147, -154, -161, -169, -176, -183, | |
22 -190, -196, -202, -208, -213, -218, -222, -225, -227, -228, | |
23 -228, -227, -224, -221, -215, -208, -200, -189, -177, -163, | |
24 -146, -127, -106, -83, -57, -29, 2, 36, 72, 111, | |
25 153, 197, 244, 294, 347, 401, 459, 519, 581, 645, | |
26 711, 779, 848, 919, 991, 1064, 1137, 1210, 1283, 1356, | |
27 1428, 1498, 1567, 1634, 1698, 1759, 1817, 1870, 1919, 1962, | |
28 2001, 2032, 2057, 2075, 2085, 2087, 2080, 2063, 2037, 2000, | |
29 1952, 1893, 1822, 1739, 1644, 1535, 1414, 1280, 1131, 970, | |
30 794, 605, 402, 185, -45, -288, -545, -814, -1095, -1388, | |
31 -1692, -2006, -2330, -2663, -3004, -3351, -3705, -4063, -4425, -4788, | |
32 -5153, -5517, -5879, -6237, -6589, -6935, -7271, -7597, -7910, -8209, | |
33 -8491, -8755, -8998, -9219, -9416, -9585, -9727, -9838, -9916, -9959, | |
34 -9966, -9935, -9863, -9750, -9592, -9389, -9139, -8840, -8492, -8092, | |
35 -7640, -7134, -6574, -5959, -5288, -4561, -3776, -2935, -2037, -1082, | |
36 -70, 998, 2122, 3300, 4533, 5818, 7154, 8540, 9975, 11455, | |
37 12980, 14548, 16155, 17799, 19478, 21189, 22929, 24694, 26482, 28289, | |
38 30112, 31947, 33791, 35640, 37489, 39336, 41176, 43006, 44821, 46617, | |
39 48390, 50137, 51853, 53534, 55178, 56778, 58333, 59838, 61289, 62684, | |
40 64019, 65290, 66494, 67629, 68692, 69679, 70590, 71420, 72169, 72835, | |
41 73415, 73908, 74313, 74630, 74856, 74992, 75038 }; | |
42 | |
43 void make_decode_tables(long scaleval) | |
44 { | |
45 int i,j,k,kr,divv; | |
46 real *table,*costab; | |
47 | |
48 | |
49 for(i=0;i<5;i++) | |
50 { | |
51 kr=0x10>>i; divv=0x40>>i; | |
52 costab = pnts[i]; | |
53 for(k=0;k<kr;k++) | |
54 costab[k] = 1.0 / (2.0 * cos(M_PI * ((double) k * 2.0 + 1.0) / (double) divv)); | |
55 } | |
56 | |
57 table = decwin; | |
58 scaleval = -scaleval; | |
59 for(i=0,j=0;i<256;i++,j++,table+=32) | |
60 { | |
61 if(table < decwin+512+16) | |
62 table[16] = table[0] = (double) intwinbase[j] / 65536.0 * (double) scaleval; | |
63 if(i % 32 == 31) | |
64 table -= 1023; | |
65 if(i % 64 == 63) | |
66 scaleval = - scaleval; | |
67 } | |
68 | |
69 for( /* i=256 */ ;i<512;i++,j--,table+=32) | |
70 { | |
71 if(table < decwin+512+16) | |
72 table[16] = table[0] = (double) intwinbase[j] / 65536.0 * (double) scaleval; | |
73 if(i % 32 == 31) | |
74 table -= 1023; | |
75 if(i % 64 == 63) | |
76 scaleval = - scaleval; | |
77 } | |
78 } | |
79 | |
80 |