1.1 --- /dev/null Thu Jan 01 00:00:00 1970 +0000
1.2 +++ b/media/libopus/silk/Inlines.h Wed Dec 31 06:09:35 2014 +0100
1.3 @@ -0,0 +1,188 @@
1.4 +/***********************************************************************
1.5 +Copyright (c) 2006-2011, Skype Limited. All rights reserved.
1.6 +Redistribution and use in source and binary forms, with or without
1.7 +modification, are permitted provided that the following conditions
1.8 +are met:
1.9 +- Redistributions of source code must retain the above copyright notice,
1.10 +this list of conditions and the following disclaimer.
1.11 +- Redistributions in binary form must reproduce the above copyright
1.12 +notice, this list of conditions and the following disclaimer in the
1.13 +documentation and/or other materials provided with the distribution.
1.14 +- Neither the name of Internet Society, IETF or IETF Trust, nor the
1.15 +names of specific contributors, may be used to endorse or promote
1.16 +products derived from this software without specific prior written
1.17 +permission.
1.18 +THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
1.19 +AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
1.20 +IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
1.21 +ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
1.22 +LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
1.23 +CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
1.24 +SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
1.25 +INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
1.26 +CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
1.27 +ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
1.28 +POSSIBILITY OF SUCH DAMAGE.
1.29 +***********************************************************************/
1.30 +
1.31 +/*! \file silk_Inlines.h
1.32 + * \brief silk_Inlines.h defines OPUS_INLINE signal processing functions.
1.33 + */
1.34 +
1.35 +#ifndef SILK_FIX_INLINES_H
1.36 +#define SILK_FIX_INLINES_H
1.37 +
1.38 +#ifdef __cplusplus
1.39 +extern "C"
1.40 +{
1.41 +#endif
1.42 +
1.43 +/* count leading zeros of opus_int64 */
1.44 +static OPUS_INLINE opus_int32 silk_CLZ64( opus_int64 in )
1.45 +{
1.46 + opus_int32 in_upper;
1.47 +
1.48 + in_upper = (opus_int32)silk_RSHIFT64(in, 32);
1.49 + if (in_upper == 0) {
1.50 + /* Search in the lower 32 bits */
1.51 + return 32 + silk_CLZ32( (opus_int32) in );
1.52 + } else {
1.53 + /* Search in the upper 32 bits */
1.54 + return silk_CLZ32( in_upper );
1.55 + }
1.56 +}
1.57 +
1.58 +/* get number of leading zeros and fractional part (the bits right after the leading one */
1.59 +static OPUS_INLINE void silk_CLZ_FRAC(
1.60 + opus_int32 in, /* I input */
1.61 + opus_int32 *lz, /* O number of leading zeros */
1.62 + opus_int32 *frac_Q7 /* O the 7 bits right after the leading one */
1.63 +)
1.64 +{
1.65 + opus_int32 lzeros = silk_CLZ32(in);
1.66 +
1.67 + * lz = lzeros;
1.68 + * frac_Q7 = silk_ROR32(in, 24 - lzeros) & 0x7f;
1.69 +}
1.70 +
1.71 +/* Approximation of square root */
1.72 +/* Accuracy: < +/- 10% for output values > 15 */
1.73 +/* < +/- 2.5% for output values > 120 */
1.74 +static OPUS_INLINE opus_int32 silk_SQRT_APPROX( opus_int32 x )
1.75 +{
1.76 + opus_int32 y, lz, frac_Q7;
1.77 +
1.78 + if( x <= 0 ) {
1.79 + return 0;
1.80 + }
1.81 +
1.82 + silk_CLZ_FRAC(x, &lz, &frac_Q7);
1.83 +
1.84 + if( lz & 1 ) {
1.85 + y = 32768;
1.86 + } else {
1.87 + y = 46214; /* 46214 = sqrt(2) * 32768 */
1.88 + }
1.89 +
1.90 + /* get scaling right */
1.91 + y >>= silk_RSHIFT(lz, 1);
1.92 +
1.93 + /* increment using fractional part of input */
1.94 + y = silk_SMLAWB(y, y, silk_SMULBB(213, frac_Q7));
1.95 +
1.96 + return y;
1.97 +}
1.98 +
1.99 +/* Divide two int32 values and return result as int32 in a given Q-domain */
1.100 +static OPUS_INLINE opus_int32 silk_DIV32_varQ( /* O returns a good approximation of "(a32 << Qres) / b32" */
1.101 + const opus_int32 a32, /* I numerator (Q0) */
1.102 + const opus_int32 b32, /* I denominator (Q0) */
1.103 + const opus_int Qres /* I Q-domain of result (>= 0) */
1.104 +)
1.105 +{
1.106 + opus_int a_headrm, b_headrm, lshift;
1.107 + opus_int32 b32_inv, a32_nrm, b32_nrm, result;
1.108 +
1.109 + silk_assert( b32 != 0 );
1.110 + silk_assert( Qres >= 0 );
1.111 +
1.112 + /* Compute number of bits head room and normalize inputs */
1.113 + a_headrm = silk_CLZ32( silk_abs(a32) ) - 1;
1.114 + a32_nrm = silk_LSHIFT(a32, a_headrm); /* Q: a_headrm */
1.115 + b_headrm = silk_CLZ32( silk_abs(b32) ) - 1;
1.116 + b32_nrm = silk_LSHIFT(b32, b_headrm); /* Q: b_headrm */
1.117 +
1.118 + /* Inverse of b32, with 14 bits of precision */
1.119 + b32_inv = silk_DIV32_16( silk_int32_MAX >> 2, silk_RSHIFT(b32_nrm, 16) ); /* Q: 29 + 16 - b_headrm */
1.120 +
1.121 + /* First approximation */
1.122 + result = silk_SMULWB(a32_nrm, b32_inv); /* Q: 29 + a_headrm - b_headrm */
1.123 +
1.124 + /* Compute residual by subtracting product of denominator and first approximation */
1.125 + /* It's OK to overflow because the final value of a32_nrm should always be small */
1.126 + a32_nrm = silk_SUB32_ovflw(a32_nrm, silk_LSHIFT_ovflw( silk_SMMUL(b32_nrm, result), 3 )); /* Q: a_headrm */
1.127 +
1.128 + /* Refinement */
1.129 + result = silk_SMLAWB(result, a32_nrm, b32_inv); /* Q: 29 + a_headrm - b_headrm */
1.130 +
1.131 + /* Convert to Qres domain */
1.132 + lshift = 29 + a_headrm - b_headrm - Qres;
1.133 + if( lshift < 0 ) {
1.134 + return silk_LSHIFT_SAT32(result, -lshift);
1.135 + } else {
1.136 + if( lshift < 32){
1.137 + return silk_RSHIFT(result, lshift);
1.138 + } else {
1.139 + /* Avoid undefined result */
1.140 + return 0;
1.141 + }
1.142 + }
1.143 +}
1.144 +
1.145 +/* Invert int32 value and return result as int32 in a given Q-domain */
1.146 +static OPUS_INLINE opus_int32 silk_INVERSE32_varQ( /* O returns a good approximation of "(1 << Qres) / b32" */
1.147 + const opus_int32 b32, /* I denominator (Q0) */
1.148 + const opus_int Qres /* I Q-domain of result (> 0) */
1.149 +)
1.150 +{
1.151 + opus_int b_headrm, lshift;
1.152 + opus_int32 b32_inv, b32_nrm, err_Q32, result;
1.153 +
1.154 + silk_assert( b32 != 0 );
1.155 + silk_assert( Qres > 0 );
1.156 +
1.157 + /* Compute number of bits head room and normalize input */
1.158 + b_headrm = silk_CLZ32( silk_abs(b32) ) - 1;
1.159 + b32_nrm = silk_LSHIFT(b32, b_headrm); /* Q: b_headrm */
1.160 +
1.161 + /* Inverse of b32, with 14 bits of precision */
1.162 + b32_inv = silk_DIV32_16( silk_int32_MAX >> 2, silk_RSHIFT(b32_nrm, 16) ); /* Q: 29 + 16 - b_headrm */
1.163 +
1.164 + /* First approximation */
1.165 + result = silk_LSHIFT(b32_inv, 16); /* Q: 61 - b_headrm */
1.166 +
1.167 + /* Compute residual by subtracting product of denominator and first approximation from one */
1.168 + err_Q32 = silk_LSHIFT( ((opus_int32)1<<29) - silk_SMULWB(b32_nrm, b32_inv), 3 ); /* Q32 */
1.169 +
1.170 + /* Refinement */
1.171 + result = silk_SMLAWW(result, err_Q32, b32_inv); /* Q: 61 - b_headrm */
1.172 +
1.173 + /* Convert to Qres domain */
1.174 + lshift = 61 - b_headrm - Qres;
1.175 + if( lshift <= 0 ) {
1.176 + return silk_LSHIFT_SAT32(result, -lshift);
1.177 + } else {
1.178 + if( lshift < 32){
1.179 + return silk_RSHIFT(result, lshift);
1.180 + }else{
1.181 + /* Avoid undefined result */
1.182 + return 0;
1.183 + }
1.184 + }
1.185 +}
1.186 +
1.187 +#ifdef __cplusplus
1.188 +}
1.189 +#endif
1.190 +
1.191 +#endif /* SILK_FIX_INLINES_H */
