diff options
Diffstat (limited to 'apps/replaygain.c')
-rw-r--r-- | apps/replaygain.c | 181 |
1 files changed, 2 insertions, 179 deletions
diff --git a/apps/replaygain.c b/apps/replaygain.c index 90944f91d0..b398afc294 100644 --- a/apps/replaygain.c +++ b/apps/replaygain.c | |||
@@ -30,188 +30,11 @@ | |||
30 | #include "metadata.h" | 30 | #include "metadata.h" |
31 | #include "debug.h" | 31 | #include "debug.h" |
32 | #include "replaygain.h" | 32 | #include "replaygain.h" |
33 | 33 | #include "fixedpoint.h" | |
34 | /* The fixed point math routines (with the exception of fp_atof) are based | ||
35 | * on oMathFP by Dan Carter (http://orbisstudios.com). | ||
36 | */ | ||
37 | |||
38 | /* 12 bits of precision gives fairly accurate result, but still allows a | ||
39 | * compact implementation. The math code supports up to 13... | ||
40 | */ | ||
41 | 34 | ||
42 | #define FP_BITS (12) | 35 | #define FP_BITS (12) |
43 | #define FP_MASK ((1 << FP_BITS) - 1) | ||
44 | #define FP_ONE (1 << FP_BITS) | 36 | #define FP_ONE (1 << FP_BITS) |
45 | #define FP_TWO (2 << FP_BITS) | ||
46 | #define FP_HALF (1 << (FP_BITS - 1)) | ||
47 | #define FP_LN2 ( 45426 >> (16 - FP_BITS)) | ||
48 | #define FP_LN2_INV ( 94548 >> (16 - FP_BITS)) | ||
49 | #define FP_EXP_ZERO ( 10922 >> (16 - FP_BITS)) | ||
50 | #define FP_EXP_ONE ( -182 >> (16 - FP_BITS)) | ||
51 | #define FP_EXP_TWO ( 4 >> (16 - FP_BITS)) | ||
52 | #define FP_INF (0x7fffffff) | ||
53 | #define FP_LN10 (150902 >> (16 - FP_BITS)) | ||
54 | |||
55 | #define FP_MAX_DIGITS (4) | ||
56 | #define FP_MAX_DIGITS_INT (10000) | ||
57 | |||
58 | #define FP_FAST_MUL_DIV | ||
59 | |||
60 | #ifdef FP_FAST_MUL_DIV | ||
61 | |||
62 | /* These macros can easily overflow, but they are good enough for our uses, | ||
63 | * and saves some code. | ||
64 | */ | ||
65 | #define fp_mul(x, y) (((x) * (y)) >> FP_BITS) | ||
66 | #define fp_div(x, y) (((x) << FP_BITS) / (y)) | ||
67 | |||
68 | #else | ||
69 | |||
70 | static long fp_mul(long x, long y) | ||
71 | { | ||
72 | long x_neg = 0; | ||
73 | long y_neg = 0; | ||
74 | long rc; | ||
75 | |||
76 | if ((x == 0) || (y == 0)) | ||
77 | { | ||
78 | return 0; | ||
79 | } | ||
80 | |||
81 | if (x < 0) | ||
82 | { | ||
83 | x_neg = 1; | ||
84 | x = -x; | ||
85 | } | ||
86 | |||
87 | if (y < 0) | ||
88 | { | ||
89 | y_neg = 1; | ||
90 | y = -y; | ||
91 | } | ||
92 | |||
93 | rc = (((x >> FP_BITS) * (y >> FP_BITS)) << FP_BITS) | ||
94 | + (((x & FP_MASK) * (y & FP_MASK)) >> FP_BITS) | ||
95 | + ((x & FP_MASK) * (y >> FP_BITS)) | ||
96 | + ((x >> FP_BITS) * (y & FP_MASK)); | ||
97 | |||
98 | if ((x_neg ^ y_neg) == 1) | ||
99 | { | ||
100 | rc = -rc; | ||
101 | } | ||
102 | |||
103 | return rc; | ||
104 | } | ||
105 | |||
106 | static long fp_div(long x, long y) | ||
107 | { | ||
108 | long x_neg = 0; | ||
109 | long y_neg = 0; | ||
110 | long shifty; | ||
111 | long rc; | ||
112 | int msb = 0; | ||
113 | int lsb = 0; | ||
114 | |||
115 | if (x == 0) | ||
116 | { | ||
117 | return 0; | ||
118 | } | ||
119 | |||
120 | if (y == 0) | ||
121 | { | ||
122 | return (x < 0) ? -FP_INF : FP_INF; | ||
123 | } | ||
124 | |||
125 | if (x < 0) | ||
126 | { | ||
127 | x_neg = 1; | ||
128 | x = -x; | ||
129 | } | ||
130 | |||
131 | if (y < 0) | ||
132 | { | ||
133 | y_neg = 1; | ||
134 | y = -y; | ||
135 | } | ||
136 | |||
137 | while ((x & BIT_N(30 - msb)) == 0) | ||
138 | { | ||
139 | msb++; | ||
140 | } | ||
141 | |||
142 | while ((y & BIT_N(lsb)) == 0) | ||
143 | { | ||
144 | lsb++; | ||
145 | } | ||
146 | |||
147 | shifty = FP_BITS - (msb + lsb); | ||
148 | rc = ((x << msb) / (y >> lsb)); | ||
149 | 37 | ||
150 | if (shifty > 0) | ||
151 | { | ||
152 | rc <<= shifty; | ||
153 | } | ||
154 | else | ||
155 | { | ||
156 | rc >>= -shifty; | ||
157 | } | ||
158 | |||
159 | if ((x_neg ^ y_neg) == 1) | ||
160 | { | ||
161 | rc = -rc; | ||
162 | } | ||
163 | |||
164 | return rc; | ||
165 | } | ||
166 | |||
167 | #endif /* FP_FAST_MUL_DIV */ | ||
168 | |||
169 | static long fp_exp(long x) | ||
170 | { | ||
171 | long k; | ||
172 | long z; | ||
173 | long R; | ||
174 | long xp; | ||
175 | |||
176 | if (x == 0) | ||
177 | { | ||
178 | return FP_ONE; | ||
179 | } | ||
180 | |||
181 | k = (fp_mul(abs(x), FP_LN2_INV) + FP_HALF) & ~FP_MASK; | ||
182 | |||
183 | if (x < 0) | ||
184 | { | ||
185 | k = -k; | ||
186 | } | ||
187 | |||
188 | x -= fp_mul(k, FP_LN2); | ||
189 | z = fp_mul(x, x); | ||
190 | R = FP_TWO + fp_mul(z, FP_EXP_ZERO + fp_mul(z, FP_EXP_ONE | ||
191 | + fp_mul(z, FP_EXP_TWO))); | ||
192 | xp = FP_ONE + fp_div(fp_mul(FP_TWO, x), R - x); | ||
193 | |||
194 | if (k < 0) | ||
195 | { | ||
196 | k = FP_ONE >> (-k >> FP_BITS); | ||
197 | } | ||
198 | else | ||
199 | { | ||
200 | k = FP_ONE << (k >> FP_BITS); | ||
201 | } | ||
202 | |||
203 | return fp_mul(k, xp); | ||
204 | } | ||
205 | |||
206 | static long fp_exp10(long x) | ||
207 | { | ||
208 | if (x == 0) | ||
209 | { | ||
210 | return FP_ONE; | ||
211 | } | ||
212 | |||
213 | return fp_exp(fp_mul(FP_LN10, x)); | ||
214 | } | ||
215 | 38 | ||
216 | static long fp_atof(const char* s, int precision) | 39 | static long fp_atof(const char* s, int precision) |
217 | { | 40 | { |
@@ -300,7 +123,7 @@ static long convert_gain(long gain) | |||
300 | gain = 17 * FP_ONE; | 123 | gain = 17 * FP_ONE; |
301 | } | 124 | } |
302 | 125 | ||
303 | gain = fp_exp10(gain / 20) << (24 - FP_BITS); | 126 | gain = fp_factor(gain, FP_BITS) << (24 - FP_BITS); |
304 | 127 | ||
305 | return gain; | 128 | return gain; |
306 | } | 129 | } |