diff options
Diffstat (limited to 'lib/rbcodec/codecs/libopus/silk/fixed/find_LPC_FIX.c')
-rw-r--r-- | lib/rbcodec/codecs/libopus/silk/fixed/find_LPC_FIX.c | 151 |
1 files changed, 151 insertions, 0 deletions
diff --git a/lib/rbcodec/codecs/libopus/silk/fixed/find_LPC_FIX.c b/lib/rbcodec/codecs/libopus/silk/fixed/find_LPC_FIX.c new file mode 100644 index 0000000000..c762a0f2a2 --- /dev/null +++ b/lib/rbcodec/codecs/libopus/silk/fixed/find_LPC_FIX.c | |||
@@ -0,0 +1,151 @@ | |||
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 "config.h" | ||
30 | #endif | ||
31 | |||
32 | #include "main_FIX.h" | ||
33 | #include "stack_alloc.h" | ||
34 | #include "tuning_parameters.h" | ||
35 | |||
36 | /* Finds LPC vector from correlations, and converts to NLSF */ | ||
37 | void silk_find_LPC_FIX( | ||
38 | silk_encoder_state *psEncC, /* I/O Encoder state */ | ||
39 | opus_int16 NLSF_Q15[], /* O NLSFs */ | ||
40 | const opus_int16 x[], /* I Input signal */ | ||
41 | const opus_int32 minInvGain_Q30 /* I Inverse of max prediction gain */ | ||
42 | ) | ||
43 | { | ||
44 | opus_int k, subfr_length; | ||
45 | opus_int32 a_Q16[ MAX_LPC_ORDER ]; | ||
46 | opus_int isInterpLower, shift; | ||
47 | opus_int32 res_nrg0, res_nrg1; | ||
48 | opus_int rshift0, rshift1; | ||
49 | |||
50 | /* Used only for LSF interpolation */ | ||
51 | opus_int32 a_tmp_Q16[ MAX_LPC_ORDER ], res_nrg_interp, res_nrg, res_tmp_nrg; | ||
52 | opus_int res_nrg_interp_Q, res_nrg_Q, res_tmp_nrg_Q; | ||
53 | opus_int16 a_tmp_Q12[ MAX_LPC_ORDER ]; | ||
54 | opus_int16 NLSF0_Q15[ MAX_LPC_ORDER ]; | ||
55 | SAVE_STACK; | ||
56 | |||
57 | subfr_length = psEncC->subfr_length + psEncC->predictLPCOrder; | ||
58 | |||
59 | /* Default: no interpolation */ | ||
60 | psEncC->indices.NLSFInterpCoef_Q2 = 4; | ||
61 | |||
62 | /* Burg AR analysis for the full frame */ | ||
63 | silk_burg_modified( &res_nrg, &res_nrg_Q, a_Q16, x, minInvGain_Q30, subfr_length, psEncC->nb_subfr, psEncC->predictLPCOrder, psEncC->arch ); | ||
64 | |||
65 | if( psEncC->useInterpolatedNLSFs && !psEncC->first_frame_after_reset && psEncC->nb_subfr == MAX_NB_SUBFR ) { | ||
66 | VARDECL( opus_int16, LPC_res ); | ||
67 | |||
68 | /* Optimal solution for last 10 ms */ | ||
69 | silk_burg_modified( &res_tmp_nrg, &res_tmp_nrg_Q, a_tmp_Q16, x + 2 * subfr_length, minInvGain_Q30, subfr_length, 2, psEncC->predictLPCOrder, psEncC->arch ); | ||
70 | |||
71 | /* subtract residual energy here, as that's easier than adding it to the */ | ||
72 | /* residual energy of the first 10 ms in each iteration of the search below */ | ||
73 | shift = res_tmp_nrg_Q - res_nrg_Q; | ||
74 | if( shift >= 0 ) { | ||
75 | if( shift < 32 ) { | ||
76 | res_nrg = res_nrg - silk_RSHIFT( res_tmp_nrg, shift ); | ||
77 | } | ||
78 | } else { | ||
79 | silk_assert( shift > -32 ); | ||
80 | res_nrg = silk_RSHIFT( res_nrg, -shift ) - res_tmp_nrg; | ||
81 | res_nrg_Q = res_tmp_nrg_Q; | ||
82 | } | ||
83 | |||
84 | /* Convert to NLSFs */ | ||
85 | silk_A2NLSF( NLSF_Q15, a_tmp_Q16, psEncC->predictLPCOrder ); | ||
86 | |||
87 | ALLOC( LPC_res, 2 * subfr_length, opus_int16 ); | ||
88 | |||
89 | /* Search over interpolation indices to find the one with lowest residual energy */ | ||
90 | for( k = 3; k >= 0; k-- ) { | ||
91 | /* Interpolate NLSFs for first half */ | ||
92 | silk_interpolate( NLSF0_Q15, psEncC->prev_NLSFq_Q15, NLSF_Q15, k, psEncC->predictLPCOrder ); | ||
93 | |||
94 | /* Convert to LPC for residual energy evaluation */ | ||
95 | silk_NLSF2A( a_tmp_Q12, NLSF0_Q15, psEncC->predictLPCOrder, psEncC->arch ); | ||
96 | |||
97 | /* Calculate residual energy with NLSF interpolation */ | ||
98 | silk_LPC_analysis_filter( LPC_res, x, a_tmp_Q12, 2 * subfr_length, psEncC->predictLPCOrder, psEncC->arch ); | ||
99 | |||
100 | silk_sum_sqr_shift( &res_nrg0, &rshift0, LPC_res + psEncC->predictLPCOrder, subfr_length - psEncC->predictLPCOrder ); | ||
101 | silk_sum_sqr_shift( &res_nrg1, &rshift1, LPC_res + psEncC->predictLPCOrder + subfr_length, subfr_length - psEncC->predictLPCOrder ); | ||
102 | |||
103 | /* Add subframe energies from first half frame */ | ||
104 | shift = rshift0 - rshift1; | ||
105 | if( shift >= 0 ) { | ||
106 | res_nrg1 = silk_RSHIFT( res_nrg1, shift ); | ||
107 | res_nrg_interp_Q = -rshift0; | ||
108 | } else { | ||
109 | res_nrg0 = silk_RSHIFT( res_nrg0, -shift ); | ||
110 | res_nrg_interp_Q = -rshift1; | ||
111 | } | ||
112 | res_nrg_interp = silk_ADD32( res_nrg0, res_nrg1 ); | ||
113 | |||
114 | /* Compare with first half energy without NLSF interpolation, or best interpolated value so far */ | ||
115 | shift = res_nrg_interp_Q - res_nrg_Q; | ||
116 | if( shift >= 0 ) { | ||
117 | if( silk_RSHIFT( res_nrg_interp, shift ) < res_nrg ) { | ||
118 | isInterpLower = silk_TRUE; | ||
119 | } else { | ||
120 | isInterpLower = silk_FALSE; | ||
121 | } | ||
122 | } else { | ||
123 | if( -shift < 32 ) { | ||
124 | if( res_nrg_interp < silk_RSHIFT( res_nrg, -shift ) ) { | ||
125 | isInterpLower = silk_TRUE; | ||
126 | } else { | ||
127 | isInterpLower = silk_FALSE; | ||
128 | } | ||
129 | } else { | ||
130 | isInterpLower = silk_FALSE; | ||
131 | } | ||
132 | } | ||
133 | |||
134 | /* Determine whether current interpolated NLSFs are best so far */ | ||
135 | if( isInterpLower == silk_TRUE ) { | ||
136 | /* Interpolation has lower residual energy */ | ||
137 | res_nrg = res_nrg_interp; | ||
138 | res_nrg_Q = res_nrg_interp_Q; | ||
139 | psEncC->indices.NLSFInterpCoef_Q2 = (opus_int8)k; | ||
140 | } | ||
141 | } | ||
142 | } | ||
143 | |||
144 | if( psEncC->indices.NLSFInterpCoef_Q2 == 4 ) { | ||
145 | /* NLSF interpolation is currently inactive, calculate NLSFs from full frame AR coefficients */ | ||
146 | silk_A2NLSF( NLSF_Q15, a_Q16, psEncC->predictLPCOrder ); | ||
147 | } | ||
148 | |||
149 | celt_assert( psEncC->indices.NLSFInterpCoef_Q2 == 4 || ( psEncC->useInterpolatedNLSFs && !psEncC->first_frame_after_reset && psEncC->nb_subfr == MAX_NB_SUBFR ) ); | ||
150 | RESTORE_STACK; | ||
151 | } | ||