|
Chris@69
|
1 /***********************************************************************
|
|
Chris@69
|
2 Copyright (c) 2006-2011, Skype Limited. All rights reserved.
|
|
Chris@69
|
3 Redistribution and use in source and binary forms, with or without
|
|
Chris@69
|
4 modification, are permitted provided that the following conditions
|
|
Chris@69
|
5 are met:
|
|
Chris@69
|
6 - Redistributions of source code must retain the above copyright notice,
|
|
Chris@69
|
7 this list of conditions and the following disclaimer.
|
|
Chris@69
|
8 - Redistributions in binary form must reproduce the above copyright
|
|
Chris@69
|
9 notice, this list of conditions and the following disclaimer in the
|
|
Chris@69
|
10 documentation and/or other materials provided with the distribution.
|
|
Chris@69
|
11 - Neither the name of Internet Society, IETF or IETF Trust, nor the
|
|
Chris@69
|
12 names of specific contributors, may be used to endorse or promote
|
|
Chris@69
|
13 products derived from this software without specific prior written
|
|
Chris@69
|
14 permission.
|
|
Chris@69
|
15 THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
|
|
Chris@69
|
16 AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
|
|
Chris@69
|
17 IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
|
|
Chris@69
|
18 ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
|
|
Chris@69
|
19 LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
|
|
Chris@69
|
20 CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
|
|
Chris@69
|
21 SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
|
|
Chris@69
|
22 INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
|
|
Chris@69
|
23 CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
|
|
Chris@69
|
24 ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
|
|
Chris@69
|
25 POSSIBILITY OF SUCH DAMAGE.
|
|
Chris@69
|
26 ***********************************************************************/
|
|
Chris@69
|
27
|
|
Chris@69
|
28 #ifdef HAVE_CONFIG_H
|
|
Chris@69
|
29 #include "config.h"
|
|
Chris@69
|
30 #endif
|
|
Chris@69
|
31
|
|
Chris@69
|
32 #include "SigProc_FIX.h"
|
|
Chris@69
|
33
|
|
Chris@69
|
34 /* Compute number of bits to right shift the sum of squares of a vector */
|
|
Chris@69
|
35 /* of int16s to make it fit in an int32 */
|
|
Chris@69
|
36 void silk_sum_sqr_shift(
|
|
Chris@69
|
37 opus_int32 *energy, /* O Energy of x, after shifting to the right */
|
|
Chris@69
|
38 opus_int *shift, /* O Number of bits right shift applied to energy */
|
|
Chris@69
|
39 const opus_int16 *x, /* I Input vector */
|
|
Chris@69
|
40 opus_int len /* I Length of input vector */
|
|
Chris@69
|
41 )
|
|
Chris@69
|
42 {
|
|
Chris@69
|
43 opus_int i, shft;
|
|
Chris@69
|
44 opus_uint32 nrg_tmp;
|
|
Chris@69
|
45 opus_int32 nrg;
|
|
Chris@69
|
46
|
|
Chris@69
|
47 /* Do a first run with the maximum shift we could have. */
|
|
Chris@69
|
48 shft = 31-silk_CLZ32(len);
|
|
Chris@69
|
49 /* Let's be conservative with rounding and start with nrg=len. */
|
|
Chris@69
|
50 nrg = len;
|
|
Chris@69
|
51 for( i = 0; i < len - 1; i += 2 ) {
|
|
Chris@69
|
52 nrg_tmp = silk_SMULBB( x[ i ], x[ i ] );
|
|
Chris@69
|
53 nrg_tmp = silk_SMLABB_ovflw( nrg_tmp, x[ i + 1 ], x[ i + 1 ] );
|
|
Chris@69
|
54 nrg = (opus_int32)silk_ADD_RSHIFT_uint( nrg, nrg_tmp, shft );
|
|
Chris@69
|
55 }
|
|
Chris@69
|
56 if( i < len ) {
|
|
Chris@69
|
57 /* One sample left to process */
|
|
Chris@69
|
58 nrg_tmp = silk_SMULBB( x[ i ], x[ i ] );
|
|
Chris@69
|
59 nrg = (opus_int32)silk_ADD_RSHIFT_uint( nrg, nrg_tmp, shft );
|
|
Chris@69
|
60 }
|
|
Chris@69
|
61 silk_assert( nrg >= 0 );
|
|
Chris@69
|
62 /* Make sure the result will fit in a 32-bit signed integer with two bits
|
|
Chris@69
|
63 of headroom. */
|
|
Chris@69
|
64 shft = silk_max_32(0, shft+3 - silk_CLZ32(nrg));
|
|
Chris@69
|
65 nrg = 0;
|
|
Chris@69
|
66 for( i = 0 ; i < len - 1; i += 2 ) {
|
|
Chris@69
|
67 nrg_tmp = silk_SMULBB( x[ i ], x[ i ] );
|
|
Chris@69
|
68 nrg_tmp = silk_SMLABB_ovflw( nrg_tmp, x[ i + 1 ], x[ i + 1 ] );
|
|
Chris@69
|
69 nrg = (opus_int32)silk_ADD_RSHIFT_uint( nrg, nrg_tmp, shft );
|
|
Chris@69
|
70 }
|
|
Chris@69
|
71 if( i < len ) {
|
|
Chris@69
|
72 /* One sample left to process */
|
|
Chris@69
|
73 nrg_tmp = silk_SMULBB( x[ i ], x[ i ] );
|
|
Chris@69
|
74 nrg = (opus_int32)silk_ADD_RSHIFT_uint( nrg, nrg_tmp, shft );
|
|
Chris@69
|
75 }
|
|
Chris@69
|
76
|
|
Chris@69
|
77 silk_assert( nrg >= 0 );
|
|
Chris@69
|
78
|
|
Chris@69
|
79 /* Output arguments */
|
|
Chris@69
|
80 *shift = shft;
|
|
Chris@69
|
81 *energy = nrg;
|
|
Chris@69
|
82 }
|
|
Chris@69
|
83
|
