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author | Sean Bartell <wingedtachikoma@gmail.com> | 2011-06-25 21:32:25 -0400 |
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committer | Nils Wallménius <nils@rockbox.org> | 2012-04-25 22:13:20 +0200 |
commit | f40bfc9267b13b54e6379dfe7539447662879d24 (patch) | |
tree | 9b20069d5e62809ff434061ad730096836f916f2 /lib/rbcodec/codecs/libwma/wmafixed.c | |
parent | a0009907de7a0107d49040d8a180f140e2eff299 (diff) | |
download | rockbox-f40bfc9267b13b54e6379dfe7539447662879d24.tar.gz rockbox-f40bfc9267b13b54e6379dfe7539447662879d24.zip |
Add codecs to librbcodec.
Change-Id: Id7f4717d51ed02d67cb9f9cb3c0ada4a81843f97
Reviewed-on: http://gerrit.rockbox.org/137
Reviewed-by: Nils Wallménius <nils@rockbox.org>
Tested-by: Nils Wallménius <nils@rockbox.org>
Diffstat (limited to 'lib/rbcodec/codecs/libwma/wmafixed.c')
-rw-r--r-- | lib/rbcodec/codecs/libwma/wmafixed.c | 223 |
1 files changed, 223 insertions, 0 deletions
diff --git a/lib/rbcodec/codecs/libwma/wmafixed.c b/lib/rbcodec/codecs/libwma/wmafixed.c new file mode 100644 index 0000000000..bdf87a548b --- /dev/null +++ b/lib/rbcodec/codecs/libwma/wmafixed.c | |||
@@ -0,0 +1,223 @@ | |||
1 | /**************************************************************************** | ||
2 | * __________ __ ___. | ||
3 | * Open \______ \ ____ ____ | | _\_ |__ _______ ___ | ||
4 | * Source | _// _ \_/ ___\| |/ /| __ \ / _ \ \/ / | ||
5 | * Jukebox | | ( <_> ) \___| < | \_\ ( <_> > < < | ||
6 | * Firmware |____|_ /\____/ \___ >__|_ \|___ /\____/__/\_ \ | ||
7 | * \/ \/ \/ \/ \/ | ||
8 | * | ||
9 | * Copyright (C) 2007 Michael Giacomelli | ||
10 | * | ||
11 | * This program is free software; you can redistribute it and/or | ||
12 | * modify it under the terms of the GNU General Public License | ||
13 | * as published by the Free Software Foundation; either version 2 | ||
14 | * of the License, or (at your option) any later version. | ||
15 | * | ||
16 | * This software is distributed on an "AS IS" basis, WITHOUT WARRANTY OF ANY | ||
17 | * KIND, either express or implied. | ||
18 | * | ||
19 | ****************************************************************************/ | ||
20 | |||
21 | #include "wmadec.h" | ||
22 | #include "wmafixed.h" | ||
23 | #include <codecs.h> | ||
24 | |||
25 | fixed64 IntTo64(int x){ | ||
26 | fixed64 res = 0; | ||
27 | unsigned char *p = (unsigned char *)&res; | ||
28 | |||
29 | #ifdef ROCKBOX_BIG_ENDIAN | ||
30 | p[5] = x & 0xff; | ||
31 | p[4] = (x & 0xff00)>>8; | ||
32 | p[3] = (x & 0xff0000)>>16; | ||
33 | p[2] = (x & 0xff000000)>>24; | ||
34 | #else | ||
35 | p[2] = x & 0xff; | ||
36 | p[3] = (x & 0xff00)>>8; | ||
37 | p[4] = (x & 0xff0000)>>16; | ||
38 | p[5] = (x & 0xff000000)>>24; | ||
39 | #endif | ||
40 | return res; | ||
41 | } | ||
42 | |||
43 | int IntFrom64(fixed64 x) | ||
44 | { | ||
45 | int res = 0; | ||
46 | unsigned char *p = (unsigned char *)&x; | ||
47 | |||
48 | #ifdef ROCKBOX_BIG_ENDIAN | ||
49 | res = p[5] | (p[4]<<8) | (p[3]<<16) | (p[2]<<24); | ||
50 | #else | ||
51 | res = p[2] | (p[3]<<8) | (p[4]<<16) | (p[5]<<24); | ||
52 | #endif | ||
53 | return res; | ||
54 | } | ||
55 | |||
56 | fixed32 Fixed32From64(fixed64 x) | ||
57 | { | ||
58 | return x & 0xFFFFFFFF; | ||
59 | } | ||
60 | |||
61 | fixed64 Fixed32To64(fixed32 x) | ||
62 | { | ||
63 | return (fixed64)x; | ||
64 | } | ||
65 | |||
66 | /* | ||
67 | Not performance senstitive code here | ||
68 | |||
69 | */ | ||
70 | |||
71 | fixed32 fixdiv32(fixed32 x, fixed32 y) | ||
72 | { | ||
73 | fixed64 temp; | ||
74 | |||
75 | if(x == 0) | ||
76 | return 0; | ||
77 | if(y == 0) | ||
78 | return 0x7fffffff; | ||
79 | temp = x; | ||
80 | temp <<= PRECISION; | ||
81 | return (fixed32)(temp / y); | ||
82 | } | ||
83 | |||
84 | fixed64 fixdiv64(fixed64 x, fixed64 y) | ||
85 | { | ||
86 | fixed64 temp; | ||
87 | |||
88 | if(x == 0) | ||
89 | return 0; | ||
90 | if(y == 0) | ||
91 | return 0x07ffffffffffffffLL; | ||
92 | temp = x; | ||
93 | temp <<= PRECISION64; | ||
94 | return (fixed64)(temp / y); | ||
95 | } | ||
96 | |||
97 | fixed32 fixsqrt32(fixed32 x) | ||
98 | { | ||
99 | |||
100 | unsigned long r = 0, s, v = (unsigned long)x; | ||
101 | |||
102 | #define STEP(k) s = r + (1 << k * 2); r >>= 1; \ | ||
103 | if (s <= v) { v -= s; r |= (1 << k * 2); } | ||
104 | |||
105 | STEP(15); | ||
106 | STEP(14); | ||
107 | STEP(13); | ||
108 | STEP(12); | ||
109 | STEP(11); | ||
110 | STEP(10); | ||
111 | STEP(9); | ||
112 | STEP(8); | ||
113 | STEP(7); | ||
114 | STEP(6); | ||
115 | STEP(5); | ||
116 | STEP(4); | ||
117 | STEP(3); | ||
118 | STEP(2); | ||
119 | STEP(1); | ||
120 | STEP(0); | ||
121 | |||
122 | return (fixed32)(r << (PRECISION / 2)); | ||
123 | } | ||
124 | |||
125 | |||
126 | static const long cordic_circular_gain = 0xb2458939; /* 0.607252929 */ | ||
127 | |||
128 | /* Table of values of atan(2^-i) in 0.32 format fractions of pi where pi = 0xffffffff / 2 */ | ||
129 | static const unsigned long atan_table[] = { | ||
130 | 0x1fffffff, /* +0.785398163 (or pi/4) */ | ||
131 | 0x12e4051d, /* +0.463647609 */ | ||
132 | 0x09fb385b, /* +0.244978663 */ | ||
133 | 0x051111d4, /* +0.124354995 */ | ||
134 | 0x028b0d43, /* +0.062418810 */ | ||
135 | 0x0145d7e1, /* +0.031239833 */ | ||
136 | 0x00a2f61e, /* +0.015623729 */ | ||
137 | 0x00517c55, /* +0.007812341 */ | ||
138 | 0x0028be53, /* +0.003906230 */ | ||
139 | 0x00145f2e, /* +0.001953123 */ | ||
140 | 0x000a2f98, /* +0.000976562 */ | ||
141 | 0x000517cc, /* +0.000488281 */ | ||
142 | 0x00028be6, /* +0.000244141 */ | ||
143 | 0x000145f3, /* +0.000122070 */ | ||
144 | 0x0000a2f9, /* +0.000061035 */ | ||
145 | 0x0000517c, /* +0.000030518 */ | ||
146 | 0x000028be, /* +0.000015259 */ | ||
147 | 0x0000145f, /* +0.000007629 */ | ||
148 | 0x00000a2f, /* +0.000003815 */ | ||
149 | 0x00000517, /* +0.000001907 */ | ||
150 | 0x0000028b, /* +0.000000954 */ | ||
151 | 0x00000145, /* +0.000000477 */ | ||
152 | 0x000000a2, /* +0.000000238 */ | ||
153 | 0x00000051, /* +0.000000119 */ | ||
154 | 0x00000028, /* +0.000000060 */ | ||
155 | 0x00000014, /* +0.000000030 */ | ||
156 | 0x0000000a, /* +0.000000015 */ | ||
157 | 0x00000005, /* +0.000000007 */ | ||
158 | 0x00000002, /* +0.000000004 */ | ||
159 | 0x00000001, /* +0.000000002 */ | ||
160 | 0x00000000, /* +0.000000001 */ | ||
161 | 0x00000000, /* +0.000000000 */ | ||
162 | }; | ||
163 | |||
164 | /** | ||
165 | * Implements sin and cos using CORDIC rotation. | ||
166 | * | ||
167 | * @param phase has range from 0 to 0xffffffff, representing 0 and | ||
168 | * 2*pi respectively. | ||
169 | * @param cos return address for cos | ||
170 | * @return sin of phase, value is a signed value from LONG_MIN to LONG_MAX, | ||
171 | * representing -1 and 1 respectively. | ||
172 | * | ||
173 | * Gives at least 24 bits precision (last 2-8 bits or so are probably off) | ||
174 | */ | ||
175 | |||
176 | long fsincos(unsigned long phase, fixed32 *cos) | ||
177 | { | ||
178 | int32_t x, x1, y, y1; | ||
179 | unsigned long z, z1; | ||
180 | int i; | ||
181 | |||
182 | /* Setup initial vector */ | ||
183 | x = cordic_circular_gain; | ||
184 | y = 0; | ||
185 | z = phase; | ||
186 | |||
187 | /* The phase has to be somewhere between 0..pi for this to work right */ | ||
188 | if (z < 0xffffffff / 4) { | ||
189 | /* z in first quadrant, z += pi/2 to correct */ | ||
190 | x = -x; | ||
191 | z += 0xffffffff / 4; | ||
192 | } else if (z < 3 * (0xffffffff / 4)) { | ||
193 | /* z in third quadrant, z -= pi/2 to correct */ | ||
194 | z -= 0xffffffff / 4; | ||
195 | } else { | ||
196 | /* z in fourth quadrant, z -= 3pi/2 to correct */ | ||
197 | x = -x; | ||
198 | z -= 3 * (0xffffffff / 4); | ||
199 | } | ||
200 | |||
201 | /* Each iteration adds roughly 1-bit of extra precision */ | ||
202 | for (i = 0; i < 31; i++) { | ||
203 | x1 = x >> i; | ||
204 | y1 = y >> i; | ||
205 | z1 = atan_table[i]; | ||
206 | |||
207 | /* Decided which direction to rotate vector. Pivot point is pi/2 */ | ||
208 | if (z >= 0xffffffff / 4) { | ||
209 | x -= y1; | ||
210 | y += x1; | ||
211 | z -= z1; | ||
212 | } else { | ||
213 | x += y1; | ||
214 | y -= x1; | ||
215 | z += z1; | ||
216 | } | ||
217 | } | ||
218 | |||
219 | if (cos) | ||
220 | *cos = x; | ||
221 | |||
222 | return y; | ||
223 | } | ||