diff options
Diffstat (limited to 'lib/rbcodec/codecs/libopus/celt/celt_lpc.c')
-rw-r--r-- | lib/rbcodec/codecs/libopus/celt/celt_lpc.c | 188 |
1 files changed, 188 insertions, 0 deletions
diff --git a/lib/rbcodec/codecs/libopus/celt/celt_lpc.c b/lib/rbcodec/codecs/libopus/celt/celt_lpc.c new file mode 100644 index 0000000000..66aed1de09 --- /dev/null +++ b/lib/rbcodec/codecs/libopus/celt/celt_lpc.c | |||
@@ -0,0 +1,188 @@ | |||
1 | /* Copyright (c) 2009-2010 Xiph.Org Foundation | ||
2 | Written by Jean-Marc Valin */ | ||
3 | /* | ||
4 | Redistribution and use in source and binary forms, with or without | ||
5 | modification, are permitted provided that the following conditions | ||
6 | are met: | ||
7 | |||
8 | - Redistributions of source code must retain the above copyright | ||
9 | notice, this list of conditions and the following disclaimer. | ||
10 | |||
11 | - Redistributions in binary form must reproduce the above copyright | ||
12 | notice, this list of conditions and the following disclaimer in the | ||
13 | documentation and/or other materials provided with the distribution. | ||
14 | |||
15 | THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS | ||
16 | ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT | ||
17 | LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR | ||
18 | A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER | ||
19 | OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, | ||
20 | EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, | ||
21 | PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR | ||
22 | PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF | ||
23 | LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING | ||
24 | NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS | ||
25 | SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. | ||
26 | */ | ||
27 | |||
28 | #ifdef HAVE_CONFIG_H | ||
29 | #include "opus_config.h" | ||
30 | #endif | ||
31 | |||
32 | #include "celt_lpc.h" | ||
33 | #include "stack_alloc.h" | ||
34 | #include "mathops.h" | ||
35 | |||
36 | void _celt_lpc( | ||
37 | opus_val16 *_lpc, /* out: [0...p-1] LPC coefficients */ | ||
38 | const opus_val32 *ac, /* in: [0...p] autocorrelation values */ | ||
39 | int p | ||
40 | ) | ||
41 | { | ||
42 | int i, j; | ||
43 | opus_val32 r; | ||
44 | opus_val32 error = ac[0]; | ||
45 | #ifdef FIXED_POINT | ||
46 | opus_val32 lpc[LPC_ORDER]; | ||
47 | #else | ||
48 | float *lpc = _lpc; | ||
49 | #endif | ||
50 | |||
51 | for (i = 0; i < p; i++) | ||
52 | lpc[i] = 0; | ||
53 | if (ac[0] != 0) | ||
54 | { | ||
55 | for (i = 0; i < p; i++) { | ||
56 | /* Sum up this iteration's reflection coefficient */ | ||
57 | opus_val32 rr = 0; | ||
58 | for (j = 0; j < i; j++) | ||
59 | rr += MULT32_32_Q31(lpc[j],ac[i - j]); | ||
60 | rr += SHR32(ac[i + 1],3); | ||
61 | r = -frac_div32(SHL32(rr,3), error); | ||
62 | /* Update LPC coefficients and total error */ | ||
63 | lpc[i] = SHR32(r,3); | ||
64 | for (j = 0; j < (i+1)>>1; j++) | ||
65 | { | ||
66 | opus_val32 tmp1, tmp2; | ||
67 | tmp1 = lpc[j]; | ||
68 | tmp2 = lpc[i-1-j]; | ||
69 | lpc[j] = tmp1 + MULT32_32_Q31(r,tmp2); | ||
70 | lpc[i-1-j] = tmp2 + MULT32_32_Q31(r,tmp1); | ||
71 | } | ||
72 | |||
73 | error = error - MULT32_32_Q31(MULT32_32_Q31(r,r),error); | ||
74 | /* Bail out once we get 30 dB gain */ | ||
75 | #ifdef FIXED_POINT | ||
76 | if (error<SHR32(ac[0],10)) | ||
77 | break; | ||
78 | #else | ||
79 | if (error<.001f*ac[0]) | ||
80 | break; | ||
81 | #endif | ||
82 | } | ||
83 | } | ||
84 | #ifdef FIXED_POINT | ||
85 | for (i=0;i<p;i++) | ||
86 | _lpc[i] = ROUND16(lpc[i],16); | ||
87 | #endif | ||
88 | } | ||
89 | |||
90 | void celt_fir(const opus_val16 *x, | ||
91 | const opus_val16 *num, | ||
92 | opus_val16 *y, | ||
93 | int N, | ||
94 | int ord, | ||
95 | opus_val16 *mem) | ||
96 | { | ||
97 | int i,j; | ||
98 | |||
99 | for (i=0;i<N;i++) | ||
100 | { | ||
101 | opus_val32 sum = SHL32(EXTEND32(x[i]), SIG_SHIFT); | ||
102 | for (j=0;j<ord;j++) | ||
103 | { | ||
104 | sum += MULT16_16(num[j],mem[j]); | ||
105 | } | ||
106 | for (j=ord-1;j>=1;j--) | ||
107 | { | ||
108 | mem[j]=mem[j-1]; | ||
109 | } | ||
110 | mem[0] = x[i]; | ||
111 | y[i] = ROUND16(sum, SIG_SHIFT); | ||
112 | } | ||
113 | } | ||
114 | |||
115 | void celt_iir(const opus_val32 *x, | ||
116 | const opus_val16 *den, | ||
117 | opus_val32 *y, | ||
118 | int N, | ||
119 | int ord, | ||
120 | opus_val16 *mem) | ||
121 | { | ||
122 | int i,j; | ||
123 | for (i=0;i<N;i++) | ||
124 | { | ||
125 | opus_val32 sum = x[i]; | ||
126 | for (j=0;j<ord;j++) | ||
127 | { | ||
128 | sum -= MULT16_16(den[j],mem[j]); | ||
129 | } | ||
130 | for (j=ord-1;j>=1;j--) | ||
131 | { | ||
132 | mem[j]=mem[j-1]; | ||
133 | } | ||
134 | mem[0] = ROUND16(sum,SIG_SHIFT); | ||
135 | y[i] = sum; | ||
136 | } | ||
137 | } | ||
138 | |||
139 | void _celt_autocorr( | ||
140 | const opus_val16 *x, /* in: [0...n-1] samples x */ | ||
141 | opus_val32 *ac, /* out: [0...lag-1] ac values */ | ||
142 | const opus_val16 *window, | ||
143 | int overlap, | ||
144 | int lag, | ||
145 | int n | ||
146 | ) | ||
147 | { | ||
148 | opus_val32 d; | ||
149 | int i; | ||
150 | VARDECL(opus_val16, xx); | ||
151 | SAVE_STACK; | ||
152 | ALLOC(xx, n, opus_val16); | ||
153 | celt_assert(n>0); | ||
154 | celt_assert(overlap>=0); | ||
155 | for (i=0;i<n;i++) | ||
156 | xx[i] = x[i]; | ||
157 | for (i=0;i<overlap;i++) | ||
158 | { | ||
159 | xx[i] = MULT16_16_Q15(x[i],window[i]); | ||
160 | xx[n-i-1] = MULT16_16_Q15(x[n-i-1],window[i]); | ||
161 | } | ||
162 | #ifdef FIXED_POINT | ||
163 | { | ||
164 | opus_val32 ac0=0; | ||
165 | int shift; | ||
166 | for(i=0;i<n;i++) | ||
167 | ac0 += SHR32(MULT16_16(xx[i],xx[i]),9); | ||
168 | ac0 += 1+n; | ||
169 | |||
170 | shift = celt_ilog2(ac0)-30+10; | ||
171 | shift = (shift+1)/2; | ||
172 | for(i=0;i<n;i++) | ||
173 | xx[i] = VSHR32(xx[i], shift); | ||
174 | } | ||
175 | #endif | ||
176 | while (lag>=0) | ||
177 | { | ||
178 | for (i = lag, d = 0; i < n; i++) | ||
179 | d += xx[i] * xx[i-lag]; | ||
180 | ac[lag] = d; | ||
181 | /*printf ("%f ", ac[lag]);*/ | ||
182 | lag--; | ||
183 | } | ||
184 | /*printf ("\n");*/ | ||
185 | ac[0] += 10; | ||
186 | |||
187 | RESTORE_STACK; | ||
188 | } | ||