diff options
Diffstat (limited to 'lib/rbcodec/codecs/libopus/silk/fixed/schur64_FIX.c')
-rw-r--r-- | lib/rbcodec/codecs/libopus/silk/fixed/schur64_FIX.c | 93 |
1 files changed, 93 insertions, 0 deletions
diff --git a/lib/rbcodec/codecs/libopus/silk/fixed/schur64_FIX.c b/lib/rbcodec/codecs/libopus/silk/fixed/schur64_FIX.c new file mode 100644 index 0000000000..4b7e19ea59 --- /dev/null +++ b/lib/rbcodec/codecs/libopus/silk/fixed/schur64_FIX.c | |||
@@ -0,0 +1,93 @@ | |||
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 "SigProc_FIX.h" | ||
33 | |||
34 | /* Slower than schur(), but more accurate. */ | ||
35 | /* Uses SMULL(), available on armv4 */ | ||
36 | opus_int32 silk_schur64( /* O returns residual energy */ | ||
37 | opus_int32 rc_Q16[], /* O Reflection coefficients [order] Q16 */ | ||
38 | const opus_int32 c[], /* I Correlations [order+1] */ | ||
39 | opus_int32 order /* I Prediction order */ | ||
40 | ) | ||
41 | { | ||
42 | opus_int k, n; | ||
43 | opus_int32 C[ SILK_MAX_ORDER_LPC + 1 ][ 2 ]; | ||
44 | opus_int32 Ctmp1_Q30, Ctmp2_Q30, rc_tmp_Q31; | ||
45 | |||
46 | celt_assert( order >= 0 && order <= SILK_MAX_ORDER_LPC ); | ||
47 | |||
48 | /* Check for invalid input */ | ||
49 | if( c[ 0 ] <= 0 ) { | ||
50 | silk_memset( rc_Q16, 0, order * sizeof( opus_int32 ) ); | ||
51 | return 0; | ||
52 | } | ||
53 | |||
54 | k = 0; | ||
55 | do { | ||
56 | C[ k ][ 0 ] = C[ k ][ 1 ] = c[ k ]; | ||
57 | } while( ++k <= order ); | ||
58 | |||
59 | for( k = 0; k < order; k++ ) { | ||
60 | /* Check that we won't be getting an unstable rc, otherwise stop here. */ | ||
61 | if (silk_abs_int32(C[ k + 1 ][ 0 ]) >= C[ 0 ][ 1 ]) { | ||
62 | if ( C[ k + 1 ][ 0 ] > 0 ) { | ||
63 | rc_Q16[ k ] = -SILK_FIX_CONST( .99f, 16 ); | ||
64 | } else { | ||
65 | rc_Q16[ k ] = SILK_FIX_CONST( .99f, 16 ); | ||
66 | } | ||
67 | k++; | ||
68 | break; | ||
69 | } | ||
70 | |||
71 | /* Get reflection coefficient: divide two Q30 values and get result in Q31 */ | ||
72 | rc_tmp_Q31 = silk_DIV32_varQ( -C[ k + 1 ][ 0 ], C[ 0 ][ 1 ], 31 ); | ||
73 | |||
74 | /* Save the output */ | ||
75 | rc_Q16[ k ] = silk_RSHIFT_ROUND( rc_tmp_Q31, 15 ); | ||
76 | |||
77 | /* Update correlations */ | ||
78 | for( n = 0; n < order - k; n++ ) { | ||
79 | Ctmp1_Q30 = C[ n + k + 1 ][ 0 ]; | ||
80 | Ctmp2_Q30 = C[ n ][ 1 ]; | ||
81 | |||
82 | /* Multiply and add the highest int32 */ | ||
83 | C[ n + k + 1 ][ 0 ] = Ctmp1_Q30 + silk_SMMUL( silk_LSHIFT( Ctmp2_Q30, 1 ), rc_tmp_Q31 ); | ||
84 | C[ n ][ 1 ] = Ctmp2_Q30 + silk_SMMUL( silk_LSHIFT( Ctmp1_Q30, 1 ), rc_tmp_Q31 ); | ||
85 | } | ||
86 | } | ||
87 | |||
88 | for(; k < order; k++ ) { | ||
89 | rc_Q16[ k ] = 0; | ||
90 | } | ||
91 | |||
92 | return silk_max_32( 1, C[ 0 ][ 1 ] ); | ||
93 | } | ||