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author | Frederik M J Vestre <freqmod@gmail.com> | 2012-07-26 14:38:32 +0200 |
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committer | Bertrik Sikken <bertrik@sikken.nl> | 2012-09-20 20:47:44 +0200 |
commit | 1b8e3801b2444f6e466e1b7c09cfc51605e80fb3 (patch) | |
tree | bd1d6fe08452d388d0d160ec02e03963f3f9525d /lib/rbcodec/codecs/libopus/silk/NLSF2A.c | |
parent | 72ebcbf73b4db911d517a66c820fdceccb8ec798 (diff) | |
download | rockbox-1b8e3801b2444f6e466e1b7c09cfc51605e80fb3.tar.gz rockbox-1b8e3801b2444f6e466e1b7c09cfc51605e80fb3.zip |
Initial opus codec support
Synchronised with opus repo on github (https://github.com/freqmod/rockbox-opus)
Status:
* Seeking ported from speex, but fails on some cases (e.g. seek to granule 0)
* ReplayGain parsing needs to be reworked, we do vorbis-style replaygain now.
http://wiki.xiph.org/OggOpus#Comment_Header explicitly forbids these in
favour of R128_TRACK_GAIN tag.
* No optimisation yet, source files still nearly identical to opus upstream
* Multi-stream opus files may not be parsed correctly
Change-Id: Ia66f1027dc1d288083e3c57b2816700078376f9a
Reviewed-on: http://gerrit.rockbox.org/300
Reviewed-by: Bertrik Sikken <bertrik@sikken.nl>
Tested-by: Bertrik Sikken <bertrik@sikken.nl>
Diffstat (limited to 'lib/rbcodec/codecs/libopus/silk/NLSF2A.c')
-rw-r--r-- | lib/rbcodec/codecs/libopus/silk/NLSF2A.c | 178 |
1 files changed, 178 insertions, 0 deletions
diff --git a/lib/rbcodec/codecs/libopus/silk/NLSF2A.c b/lib/rbcodec/codecs/libopus/silk/NLSF2A.c new file mode 100644 index 0000000000..ffc2a96939 --- /dev/null +++ b/lib/rbcodec/codecs/libopus/silk/NLSF2A.c | |||
@@ -0,0 +1,178 @@ | |||
1 | /*********************************************************************** | ||
2 | Copyright (c) 2006-2011, Skype Limited. All rights reserved. | ||
3 | Redistribution and use in source and binary forms, with or without | ||
4 | modification, are permitted provided that the following conditions | ||
5 | are met: | ||
6 | - Redistributions of source code must retain the above copyright notice, | ||
7 | this list of conditions and the following disclaimer. | ||
8 | - Redistributions in binary form must reproduce the above copyright | ||
9 | notice, this list of conditions and the following disclaimer in the | ||
10 | documentation and/or other materials provided with the distribution. | ||
11 | - Neither the name of Internet Society, IETF or IETF Trust, nor the | ||
12 | names of specific contributors, may be used to endorse or promote | ||
13 | products derived from this software without specific prior written | ||
14 | permission. | ||
15 | THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS “AS IS” | ||
16 | AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE | ||
17 | IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE | ||
18 | ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE | ||
19 | LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR | ||
20 | CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF | ||
21 | SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS | ||
22 | INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN | ||
23 | CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) | ||
24 | ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE | ||
25 | POSSIBILITY OF SUCH DAMAGE. | ||
26 | ***********************************************************************/ | ||
27 | |||
28 | #ifdef HAVE_CONFIG_H | ||
29 | #include "opus_config.h" | ||
30 | #endif | ||
31 | |||
32 | /* conversion between prediction filter coefficients and LSFs */ | ||
33 | /* order should be even */ | ||
34 | /* a piecewise linear approximation maps LSF <-> cos(LSF) */ | ||
35 | /* therefore the result is not accurate LSFs, but the two */ | ||
36 | /* functions are accurate inverses of each other */ | ||
37 | |||
38 | #include "SigProc_FIX.h" | ||
39 | #include "tables.h" | ||
40 | |||
41 | #define QA 16 | ||
42 | |||
43 | /* helper function for NLSF2A(..) */ | ||
44 | static inline void silk_NLSF2A_find_poly( | ||
45 | opus_int32 *out, /* O intermediate polynomial, QA [dd+1] */ | ||
46 | const opus_int32 *cLSF, /* I vector of interleaved 2*cos(LSFs), QA [d] */ | ||
47 | opus_int dd /* I polynomial order (= 1/2 * filter order) */ | ||
48 | ) | ||
49 | { | ||
50 | opus_int k, n; | ||
51 | opus_int32 ftmp; | ||
52 | |||
53 | out[0] = silk_LSHIFT( 1, QA ); | ||
54 | out[1] = -cLSF[0]; | ||
55 | for( k = 1; k < dd; k++ ) { | ||
56 | ftmp = cLSF[2*k]; /* QA*/ | ||
57 | out[k+1] = silk_LSHIFT( out[k-1], 1 ) - (opus_int32)silk_RSHIFT_ROUND64( silk_SMULL( ftmp, out[k] ), QA ); | ||
58 | for( n = k; n > 1; n-- ) { | ||
59 | out[n] += out[n-2] - (opus_int32)silk_RSHIFT_ROUND64( silk_SMULL( ftmp, out[n-1] ), QA ); | ||
60 | } | ||
61 | out[1] -= ftmp; | ||
62 | } | ||
63 | } | ||
64 | |||
65 | /* compute whitening filter coefficients from normalized line spectral frequencies */ | ||
66 | void silk_NLSF2A( | ||
67 | opus_int16 *a_Q12, /* O monic whitening filter coefficients in Q12, [ d ] */ | ||
68 | const opus_int16 *NLSF, /* I normalized line spectral frequencies in Q15, [ d ] */ | ||
69 | const opus_int d /* I filter order (should be even) */ | ||
70 | ) | ||
71 | { | ||
72 | /* This ordering was found to maximize quality. It improves numerical accuracy of | ||
73 | silk_NLSF2A_find_poly() compared to "standard" ordering. */ | ||
74 | static const unsigned char ordering16[16] = { | ||
75 | 0, 15, 8, 7, 4, 11, 12, 3, 2, 13, 10, 5, 6, 9, 14, 1 | ||
76 | }; | ||
77 | static const unsigned char ordering10[10] = { | ||
78 | 0, 9, 6, 3, 4, 5, 8, 1, 2, 7 | ||
79 | }; | ||
80 | const unsigned char *ordering; | ||
81 | opus_int k, i, dd; | ||
82 | opus_int32 cos_LSF_QA[ SILK_MAX_ORDER_LPC ]; | ||
83 | opus_int32 P[ SILK_MAX_ORDER_LPC / 2 + 1 ], Q[ SILK_MAX_ORDER_LPC / 2 + 1 ]; | ||
84 | opus_int32 Ptmp, Qtmp, f_int, f_frac, cos_val, delta; | ||
85 | opus_int32 a32_QA1[ SILK_MAX_ORDER_LPC ]; | ||
86 | opus_int32 maxabs, absval, idx=0, sc_Q16; | ||
87 | |||
88 | silk_assert( LSF_COS_TAB_SZ_FIX == 128 ); | ||
89 | silk_assert( d==10||d==16 ); | ||
90 | |||
91 | /* convert LSFs to 2*cos(LSF), using piecewise linear curve from table */ | ||
92 | ordering = d == 16 ? ordering16 : ordering10; | ||
93 | for( k = 0; k < d; k++ ) { | ||
94 | silk_assert(NLSF[k] >= 0 ); | ||
95 | |||
96 | /* f_int on a scale 0-127 (rounded down) */ | ||
97 | f_int = silk_RSHIFT( NLSF[k], 15 - 7 ); | ||
98 | |||
99 | /* f_frac, range: 0..255 */ | ||
100 | f_frac = NLSF[k] - silk_LSHIFT( f_int, 15 - 7 ); | ||
101 | |||
102 | silk_assert(f_int >= 0); | ||
103 | silk_assert(f_int < LSF_COS_TAB_SZ_FIX ); | ||
104 | |||
105 | /* Read start and end value from table */ | ||
106 | cos_val = silk_LSFCosTab_FIX_Q12[ f_int ]; /* Q12 */ | ||
107 | delta = silk_LSFCosTab_FIX_Q12[ f_int + 1 ] - cos_val; /* Q12, with a range of 0..200 */ | ||
108 | |||
109 | /* Linear interpolation */ | ||
110 | cos_LSF_QA[ordering[k]] = silk_RSHIFT_ROUND( silk_LSHIFT( cos_val, 8 ) + silk_MUL( delta, f_frac ), 20 - QA ); /* QA */ | ||
111 | } | ||
112 | |||
113 | dd = silk_RSHIFT( d, 1 ); | ||
114 | |||
115 | /* generate even and odd polynomials using convolution */ | ||
116 | silk_NLSF2A_find_poly( P, &cos_LSF_QA[ 0 ], dd ); | ||
117 | silk_NLSF2A_find_poly( Q, &cos_LSF_QA[ 1 ], dd ); | ||
118 | |||
119 | /* convert even and odd polynomials to opus_int32 Q12 filter coefs */ | ||
120 | for( k = 0; k < dd; k++ ) { | ||
121 | Ptmp = P[ k+1 ] + P[ k ]; | ||
122 | Qtmp = Q[ k+1 ] - Q[ k ]; | ||
123 | |||
124 | /* the Ptmp and Qtmp values at this stage need to fit in int32 */ | ||
125 | a32_QA1[ k ] = -Qtmp - Ptmp; /* QA+1 */ | ||
126 | a32_QA1[ d-k-1 ] = Qtmp - Ptmp; /* QA+1 */ | ||
127 | } | ||
128 | |||
129 | /* Limit the maximum absolute value of the prediction coefficients, so that they'll fit in int16 */ | ||
130 | for( i = 0; i < 10; i++ ) { | ||
131 | /* Find maximum absolute value and its index */ | ||
132 | maxabs = 0; | ||
133 | for( k = 0; k < d; k++ ) { | ||
134 | absval = silk_abs( a32_QA1[k] ); | ||
135 | if( absval > maxabs ) { | ||
136 | maxabs = absval; | ||
137 | idx = k; | ||
138 | } | ||
139 | } | ||
140 | maxabs = silk_RSHIFT_ROUND( maxabs, QA + 1 - 12 ); /* QA+1 -> Q12 */ | ||
141 | |||
142 | if( maxabs > silk_int16_MAX ) { | ||
143 | /* Reduce magnitude of prediction coefficients */ | ||
144 | maxabs = silk_min( maxabs, 163838 ); /* ( silk_int32_MAX >> 14 ) + silk_int16_MAX = 163838 */ | ||
145 | sc_Q16 = SILK_FIX_CONST( 0.999, 16 ) - silk_DIV32( silk_LSHIFT( maxabs - silk_int16_MAX, 14 ), | ||
146 | silk_RSHIFT32( silk_MUL( maxabs, idx + 1), 2 ) ); | ||
147 | silk_bwexpander_32( a32_QA1, d, sc_Q16 ); | ||
148 | } else { | ||
149 | break; | ||
150 | } | ||
151 | } | ||
152 | |||
153 | if( i == 10 ) { | ||
154 | /* Reached the last iteration, clip the coefficients */ | ||
155 | for( k = 0; k < d; k++ ) { | ||
156 | a_Q12[ k ] = (opus_int16)silk_SAT16( silk_RSHIFT_ROUND( a32_QA1[ k ], QA + 1 - 12 ) ); /* QA+1 -> Q12 */ | ||
157 | a32_QA1[ k ] = silk_LSHIFT( (opus_int32)a_Q12[ k ], QA + 1 - 12 ); | ||
158 | } | ||
159 | } else { | ||
160 | for( k = 0; k < d; k++ ) { | ||
161 | a_Q12[ k ] = (opus_int16)silk_RSHIFT_ROUND( a32_QA1[ k ], QA + 1 - 12 ); /* QA+1 -> Q12 */ | ||
162 | } | ||
163 | } | ||
164 | |||
165 | for( i = 0; i < MAX_LPC_STABILIZE_ITERATIONS; i++ ) { | ||
166 | if( silk_LPC_inverse_pred_gain( a_Q12, d ) < SILK_FIX_CONST( 1.0 / MAX_PREDICTION_POWER_GAIN, 30 ) ) { | ||
167 | /* Prediction coefficients are (too close to) unstable; apply bandwidth expansion */ | ||
168 | /* on the unscaled coefficients, convert to Q12 and measure again */ | ||
169 | silk_bwexpander_32( a32_QA1, d, 65536 - silk_LSHIFT( 2, i ) ); | ||
170 | for( k = 0; k < d; k++ ) { | ||
171 | a_Q12[ k ] = (opus_int16)silk_RSHIFT_ROUND( a32_QA1[ k ], QA + 1 - 12 ); /* QA+1 -> Q12 */ | ||
172 | } | ||
173 | } else { | ||
174 | break; | ||
175 | } | ||
176 | } | ||
177 | } | ||
178 | |||