diff options
Diffstat (limited to 'lib/rbcodec/codecs/libopus/silk/fixed/apply_sine_window_FIX.c')
-rw-r--r-- | lib/rbcodec/codecs/libopus/silk/fixed/apply_sine_window_FIX.c | 101 |
1 files changed, 101 insertions, 0 deletions
diff --git a/lib/rbcodec/codecs/libopus/silk/fixed/apply_sine_window_FIX.c b/lib/rbcodec/codecs/libopus/silk/fixed/apply_sine_window_FIX.c new file mode 100644 index 0000000000..03e088a6de --- /dev/null +++ b/lib/rbcodec/codecs/libopus/silk/fixed/apply_sine_window_FIX.c | |||
@@ -0,0 +1,101 @@ | |||
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 | /* Apply sine window to signal vector. */ | ||
35 | /* Window types: */ | ||
36 | /* 1 -> sine window from 0 to pi/2 */ | ||
37 | /* 2 -> sine window from pi/2 to pi */ | ||
38 | /* Every other sample is linearly interpolated, for speed. */ | ||
39 | /* Window length must be between 16 and 120 (incl) and a multiple of 4. */ | ||
40 | |||
41 | /* Matlab code for table: | ||
42 | for k=16:9*4:16+2*9*4, fprintf(' %7.d,', -round(65536*pi ./ (k:4:k+8*4))); fprintf('\n'); end | ||
43 | */ | ||
44 | static const opus_int16 freq_table_Q16[ 27 ] = { | ||
45 | 12111, 9804, 8235, 7100, 6239, 5565, 5022, 4575, 4202, | ||
46 | 3885, 3612, 3375, 3167, 2984, 2820, 2674, 2542, 2422, | ||
47 | 2313, 2214, 2123, 2038, 1961, 1889, 1822, 1760, 1702, | ||
48 | }; | ||
49 | |||
50 | void silk_apply_sine_window( | ||
51 | opus_int16 px_win[], /* O Pointer to windowed signal */ | ||
52 | const opus_int16 px[], /* I Pointer to input signal */ | ||
53 | const opus_int win_type, /* I Selects a window type */ | ||
54 | const opus_int length /* I Window length, multiple of 4 */ | ||
55 | ) | ||
56 | { | ||
57 | opus_int k, f_Q16, c_Q16; | ||
58 | opus_int32 S0_Q16, S1_Q16; | ||
59 | |||
60 | celt_assert( win_type == 1 || win_type == 2 ); | ||
61 | |||
62 | /* Length must be in a range from 16 to 120 and a multiple of 4 */ | ||
63 | celt_assert( length >= 16 && length <= 120 ); | ||
64 | celt_assert( ( length & 3 ) == 0 ); | ||
65 | |||
66 | /* Frequency */ | ||
67 | k = ( length >> 2 ) - 4; | ||
68 | celt_assert( k >= 0 && k <= 26 ); | ||
69 | f_Q16 = (opus_int)freq_table_Q16[ k ]; | ||
70 | |||
71 | /* Factor used for cosine approximation */ | ||
72 | c_Q16 = silk_SMULWB( (opus_int32)f_Q16, -f_Q16 ); | ||
73 | silk_assert( c_Q16 >= -32768 ); | ||
74 | |||
75 | /* initialize state */ | ||
76 | if( win_type == 1 ) { | ||
77 | /* start from 0 */ | ||
78 | S0_Q16 = 0; | ||
79 | /* approximation of sin(f) */ | ||
80 | S1_Q16 = f_Q16 + silk_RSHIFT( length, 3 ); | ||
81 | } else { | ||
82 | /* start from 1 */ | ||
83 | S0_Q16 = ( (opus_int32)1 << 16 ); | ||
84 | /* approximation of cos(f) */ | ||
85 | S1_Q16 = ( (opus_int32)1 << 16 ) + silk_RSHIFT( c_Q16, 1 ) + silk_RSHIFT( length, 4 ); | ||
86 | } | ||
87 | |||
88 | /* Uses the recursive equation: sin(n*f) = 2 * cos(f) * sin((n-1)*f) - sin((n-2)*f) */ | ||
89 | /* 4 samples at a time */ | ||
90 | for( k = 0; k < length; k += 4 ) { | ||
91 | px_win[ k ] = (opus_int16)silk_SMULWB( silk_RSHIFT( S0_Q16 + S1_Q16, 1 ), px[ k ] ); | ||
92 | px_win[ k + 1 ] = (opus_int16)silk_SMULWB( S1_Q16, px[ k + 1] ); | ||
93 | S0_Q16 = silk_SMULWB( S1_Q16, c_Q16 ) + silk_LSHIFT( S1_Q16, 1 ) - S0_Q16 + 1; | ||
94 | S0_Q16 = silk_min( S0_Q16, ( (opus_int32)1 << 16 ) ); | ||
95 | |||
96 | px_win[ k + 2 ] = (opus_int16)silk_SMULWB( silk_RSHIFT( S0_Q16 + S1_Q16, 1 ), px[ k + 2] ); | ||
97 | px_win[ k + 3 ] = (opus_int16)silk_SMULWB( S0_Q16, px[ k + 3 ] ); | ||
98 | S1_Q16 = silk_SMULWB( S0_Q16, c_Q16 ) + silk_LSHIFT( S0_Q16, 1 ) - S1_Q16; | ||
99 | S1_Q16 = silk_min( S1_Q16, ( (opus_int32)1 << 16 ) ); | ||
100 | } | ||
101 | } | ||