mbed official / mbed-dsp

CMSIS DSP library

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cmsis_dsp/TransformFunctions/arm_cfft_q31.c@5:3762170b6d4d, 2015-11-20 (annotated)

Committer:
mbed_official
Date:
Fri Nov 20 08:45:18 2015 +0000
Revision:
5:3762170b6d4d
Synchronized with git revision 2eb940b9a73af188d3004a2575fdfbb05febe62b



Full URL: https://github.com/mbedmicro/mbed/commit/2eb940b9a73af188d3004a2575fdfbb05febe62b/



Added option to build rpc library. closes #1426

Who changed what in which revision?

UserRevisionLine numberNew contents of line
mbed_official 5:3762170b6d4d 1 /* ----------------------------------------------------------------------
mbed_official 5:3762170b6d4d 2 * Copyright (C) 2010-2014 ARM Limited. All rights reserved.
mbed_official 5:3762170b6d4d 3 *
mbed_official 5:3762170b6d4d 4 * $Date: 19. March 2015
mbed_official 5:3762170b6d4d 5 * $Revision: V.1.4.5
mbed_official 5:3762170b6d4d 6 *
mbed_official 5:3762170b6d4d 7 * Project: CMSIS DSP Library
mbed_official 5:3762170b6d4d 8 * Title: arm_cfft_q31.c
mbed_official 5:3762170b6d4d 9 *
mbed_official 5:3762170b6d4d 10 * Description: Combined Radix Decimation in Frequency CFFT fixed point processing function
mbed_official 5:3762170b6d4d 11 *
mbed_official 5:3762170b6d4d 12 * Target Processor: Cortex-M4/Cortex-M3/Cortex-M0
mbed_official 5:3762170b6d4d 13 *
mbed_official 5:3762170b6d4d 14 * Redistribution and use in source and binary forms, with or without
mbed_official 5:3762170b6d4d 15 * modification, are permitted provided that the following conditions
mbed_official 5:3762170b6d4d 16 * are met:
mbed_official 5:3762170b6d4d 17 * - Redistributions of source code must retain the above copyright
mbed_official 5:3762170b6d4d 18 * notice, this list of conditions and the following disclaimer.
mbed_official 5:3762170b6d4d 19 * - Redistributions in binary form must reproduce the above copyright
mbed_official 5:3762170b6d4d 20 * notice, this list of conditions and the following disclaimer in
mbed_official 5:3762170b6d4d 21 * the documentation and/or other materials provided with the
mbed_official 5:3762170b6d4d 22 * distribution.
mbed_official 5:3762170b6d4d 23 * - Neither the name of ARM LIMITED nor the names of its contributors
mbed_official 5:3762170b6d4d 24 * may be used to endorse or promote products derived from this
mbed_official 5:3762170b6d4d 25 * software without specific prior written permission.
mbed_official 5:3762170b6d4d 26 *
mbed_official 5:3762170b6d4d 27 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
mbed_official 5:3762170b6d4d 28 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
mbed_official 5:3762170b6d4d 29 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
mbed_official 5:3762170b6d4d 30 * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
mbed_official 5:3762170b6d4d 31 * COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
mbed_official 5:3762170b6d4d 32 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
mbed_official 5:3762170b6d4d 33 * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
mbed_official 5:3762170b6d4d 34 * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
mbed_official 5:3762170b6d4d 35 * CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
mbed_official 5:3762170b6d4d 36 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN
mbed_official 5:3762170b6d4d 37 * ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
mbed_official 5:3762170b6d4d 38 * POSSIBILITY OF SUCH DAMAGE.
mbed_official 5:3762170b6d4d 39 * -------------------------------------------------------------------- */
mbed_official 5:3762170b6d4d 40
mbed_official 5:3762170b6d4d 41 #include "arm_math.h"
mbed_official 5:3762170b6d4d 42
mbed_official 5:3762170b6d4d 43 extern void arm_radix4_butterfly_q31(
mbed_official 5:3762170b6d4d 44 q31_t * pSrc,
mbed_official 5:3762170b6d4d 45 uint32_t fftLen,
mbed_official 5:3762170b6d4d 46 q31_t * pCoef,
mbed_official 5:3762170b6d4d 47 uint32_t twidCoefModifier);
mbed_official 5:3762170b6d4d 48
mbed_official 5:3762170b6d4d 49 extern void arm_radix4_butterfly_inverse_q31(
mbed_official 5:3762170b6d4d 50 q31_t * pSrc,
mbed_official 5:3762170b6d4d 51 uint32_t fftLen,
mbed_official 5:3762170b6d4d 52 q31_t * pCoef,
mbed_official 5:3762170b6d4d 53 uint32_t twidCoefModifier);
mbed_official 5:3762170b6d4d 54
mbed_official 5:3762170b6d4d 55 extern void arm_bitreversal_32(
mbed_official 5:3762170b6d4d 56 uint32_t * pSrc,
mbed_official 5:3762170b6d4d 57 const uint16_t bitRevLen,
mbed_official 5:3762170b6d4d 58 const uint16_t * pBitRevTable);
mbed_official 5:3762170b6d4d 59
mbed_official 5:3762170b6d4d 60 void arm_cfft_radix4by2_q31(
mbed_official 5:3762170b6d4d 61 q31_t * pSrc,
mbed_official 5:3762170b6d4d 62 uint32_t fftLen,
mbed_official 5:3762170b6d4d 63 const q31_t * pCoef);
mbed_official 5:3762170b6d4d 64
mbed_official 5:3762170b6d4d 65 void arm_cfft_radix4by2_inverse_q31(
mbed_official 5:3762170b6d4d 66 q31_t * pSrc,
mbed_official 5:3762170b6d4d 67 uint32_t fftLen,
mbed_official 5:3762170b6d4d 68 const q31_t * pCoef);
mbed_official 5:3762170b6d4d 69
mbed_official 5:3762170b6d4d 70 /**
mbed_official 5:3762170b6d4d 71 * @ingroup groupTransforms
mbed_official 5:3762170b6d4d 72 */
mbed_official 5:3762170b6d4d 73
mbed_official 5:3762170b6d4d 74 /**
mbed_official 5:3762170b6d4d 75 * @addtogroup ComplexFFT
mbed_official 5:3762170b6d4d 76 * @{
mbed_official 5:3762170b6d4d 77 */
mbed_official 5:3762170b6d4d 78
mbed_official 5:3762170b6d4d 79 /**
mbed_official 5:3762170b6d4d 80 * @details
mbed_official 5:3762170b6d4d 81 * @brief Processing function for the fixed-point complex FFT in Q31 format.
mbed_official 5:3762170b6d4d 82 * @param[in] *S points to an instance of the fixed-point CFFT structure.
mbed_official 5:3762170b6d4d 83 * @param[in, out] *p1 points to the complex data buffer of size <code>2*fftLen</code>. Processing occurs in-place.
mbed_official 5:3762170b6d4d 84 * @param[in] ifftFlag flag that selects forward (ifftFlag=0) or inverse (ifftFlag=1) transform.
mbed_official 5:3762170b6d4d 85 * @param[in] bitReverseFlag flag that enables (bitReverseFlag=1) or disables (bitReverseFlag=0) bit reversal of output.
mbed_official 5:3762170b6d4d 86 * @return none.
mbed_official 5:3762170b6d4d 87 */
mbed_official 5:3762170b6d4d 88
mbed_official 5:3762170b6d4d 89 void arm_cfft_q31(
mbed_official 5:3762170b6d4d 90 const arm_cfft_instance_q31 * S,
mbed_official 5:3762170b6d4d 91 q31_t * p1,
mbed_official 5:3762170b6d4d 92 uint8_t ifftFlag,
mbed_official 5:3762170b6d4d 93 uint8_t bitReverseFlag)
mbed_official 5:3762170b6d4d 94 {
mbed_official 5:3762170b6d4d 95 uint32_t L = S->fftLen;
mbed_official 5:3762170b6d4d 96
mbed_official 5:3762170b6d4d 97 if(ifftFlag == 1u)
mbed_official 5:3762170b6d4d 98 {
mbed_official 5:3762170b6d4d 99 switch (L)
mbed_official 5:3762170b6d4d 100 {
mbed_official 5:3762170b6d4d 101 case 16:
mbed_official 5:3762170b6d4d 102 case 64:
mbed_official 5:3762170b6d4d 103 case 256:
mbed_official 5:3762170b6d4d 104 case 1024:
mbed_official 5:3762170b6d4d 105 case 4096:
mbed_official 5:3762170b6d4d 106 arm_radix4_butterfly_inverse_q31 ( p1, L, (q31_t*)S->pTwiddle, 1 );
mbed_official 5:3762170b6d4d 107 break;
mbed_official 5:3762170b6d4d 108
mbed_official 5:3762170b6d4d 109 case 32:
mbed_official 5:3762170b6d4d 110 case 128:
mbed_official 5:3762170b6d4d 111 case 512:
mbed_official 5:3762170b6d4d 112 case 2048:
mbed_official 5:3762170b6d4d 113 arm_cfft_radix4by2_inverse_q31 ( p1, L, S->pTwiddle );
mbed_official 5:3762170b6d4d 114 break;
mbed_official 5:3762170b6d4d 115 }
mbed_official 5:3762170b6d4d 116 }
mbed_official 5:3762170b6d4d 117 else
mbed_official 5:3762170b6d4d 118 {
mbed_official 5:3762170b6d4d 119 switch (L)
mbed_official 5:3762170b6d4d 120 {
mbed_official 5:3762170b6d4d 121 case 16:
mbed_official 5:3762170b6d4d 122 case 64:
mbed_official 5:3762170b6d4d 123 case 256:
mbed_official 5:3762170b6d4d 124 case 1024:
mbed_official 5:3762170b6d4d 125 case 4096:
mbed_official 5:3762170b6d4d 126 arm_radix4_butterfly_q31 ( p1, L, (q31_t*)S->pTwiddle, 1 );
mbed_official 5:3762170b6d4d 127 break;
mbed_official 5:3762170b6d4d 128
mbed_official 5:3762170b6d4d 129 case 32:
mbed_official 5:3762170b6d4d 130 case 128:
mbed_official 5:3762170b6d4d 131 case 512:
mbed_official 5:3762170b6d4d 132 case 2048:
mbed_official 5:3762170b6d4d 133 arm_cfft_radix4by2_q31 ( p1, L, S->pTwiddle );
mbed_official 5:3762170b6d4d 134 break;
mbed_official 5:3762170b6d4d 135 }
mbed_official 5:3762170b6d4d 136 }
mbed_official 5:3762170b6d4d 137
mbed_official 5:3762170b6d4d 138 if( bitReverseFlag )
mbed_official 5:3762170b6d4d 139 arm_bitreversal_32((uint32_t*)p1,S->bitRevLength,S->pBitRevTable);
mbed_official 5:3762170b6d4d 140 }
mbed_official 5:3762170b6d4d 141
mbed_official 5:3762170b6d4d 142 /**
mbed_official 5:3762170b6d4d 143 * @} end of ComplexFFT group
mbed_official 5:3762170b6d4d 144 */
mbed_official 5:3762170b6d4d 145
mbed_official 5:3762170b6d4d 146 void arm_cfft_radix4by2_q31(
mbed_official 5:3762170b6d4d 147 q31_t * pSrc,
mbed_official 5:3762170b6d4d 148 uint32_t fftLen,
mbed_official 5:3762170b6d4d 149 const q31_t * pCoef)
mbed_official 5:3762170b6d4d 150 {
mbed_official 5:3762170b6d4d 151 uint32_t i, l;
mbed_official 5:3762170b6d4d 152 uint32_t n2, ia;
mbed_official 5:3762170b6d4d 153 q31_t xt, yt, cosVal, sinVal;
mbed_official 5:3762170b6d4d 154 q31_t p0, p1;
mbed_official 5:3762170b6d4d 155
mbed_official 5:3762170b6d4d 156 n2 = fftLen >> 1;
mbed_official 5:3762170b6d4d 157 ia = 0;
mbed_official 5:3762170b6d4d 158 for (i = 0; i < n2; i++)
mbed_official 5:3762170b6d4d 159 {
mbed_official 5:3762170b6d4d 160 cosVal = pCoef[2*ia];
mbed_official 5:3762170b6d4d 161 sinVal = pCoef[2*ia + 1];
mbed_official 5:3762170b6d4d 162 ia++;
mbed_official 5:3762170b6d4d 163
mbed_official 5:3762170b6d4d 164 l = i + n2;
mbed_official 5:3762170b6d4d 165 xt = (pSrc[2 * i] >> 2) - (pSrc[2 * l] >> 2);
mbed_official 5:3762170b6d4d 166 pSrc[2 * i] = (pSrc[2 * i] >> 2) + (pSrc[2 * l] >> 2);
mbed_official 5:3762170b6d4d 167
mbed_official 5:3762170b6d4d 168 yt = (pSrc[2 * i + 1] >> 2) - (pSrc[2 * l + 1] >> 2);
mbed_official 5:3762170b6d4d 169 pSrc[2 * i + 1] = (pSrc[2 * l + 1] >> 2) + (pSrc[2 * i + 1] >> 2);
mbed_official 5:3762170b6d4d 170
mbed_official 5:3762170b6d4d 171 mult_32x32_keep32_R(p0, xt, cosVal);
mbed_official 5:3762170b6d4d 172 mult_32x32_keep32_R(p1, yt, cosVal);
mbed_official 5:3762170b6d4d 173 multAcc_32x32_keep32_R(p0, yt, sinVal);
mbed_official 5:3762170b6d4d 174 multSub_32x32_keep32_R(p1, xt, sinVal);
mbed_official 5:3762170b6d4d 175
mbed_official 5:3762170b6d4d 176 pSrc[2u * l] = p0 << 1;
mbed_official 5:3762170b6d4d 177 pSrc[2u * l + 1u] = p1 << 1;
mbed_official 5:3762170b6d4d 178
mbed_official 5:3762170b6d4d 179 }
mbed_official 5:3762170b6d4d 180
mbed_official 5:3762170b6d4d 181 // first col
mbed_official 5:3762170b6d4d 182 arm_radix4_butterfly_q31( pSrc, n2, (q31_t*)pCoef, 2u);
mbed_official 5:3762170b6d4d 183 // second col
mbed_official 5:3762170b6d4d 184 arm_radix4_butterfly_q31( pSrc + fftLen, n2, (q31_t*)pCoef, 2u);
mbed_official 5:3762170b6d4d 185
mbed_official 5:3762170b6d4d 186 for (i = 0; i < fftLen >> 1; i++)
mbed_official 5:3762170b6d4d 187 {
mbed_official 5:3762170b6d4d 188 p0 = pSrc[4*i+0];
mbed_official 5:3762170b6d4d 189 p1 = pSrc[4*i+1];
mbed_official 5:3762170b6d4d 190 xt = pSrc[4*i+2];
mbed_official 5:3762170b6d4d 191 yt = pSrc[4*i+3];
mbed_official 5:3762170b6d4d 192
mbed_official 5:3762170b6d4d 193 p0 <<= 1;
mbed_official 5:3762170b6d4d 194 p1 <<= 1;
mbed_official 5:3762170b6d4d 195 xt <<= 1;
mbed_official 5:3762170b6d4d 196 yt <<= 1;
mbed_official 5:3762170b6d4d 197
mbed_official 5:3762170b6d4d 198 pSrc[4*i+0] = p0;
mbed_official 5:3762170b6d4d 199 pSrc[4*i+1] = p1;
mbed_official 5:3762170b6d4d 200 pSrc[4*i+2] = xt;
mbed_official 5:3762170b6d4d 201 pSrc[4*i+3] = yt;
mbed_official 5:3762170b6d4d 202 }
mbed_official 5:3762170b6d4d 203
mbed_official 5:3762170b6d4d 204 }
mbed_official 5:3762170b6d4d 205
mbed_official 5:3762170b6d4d 206 void arm_cfft_radix4by2_inverse_q31(
mbed_official 5:3762170b6d4d 207 q31_t * pSrc,
mbed_official 5:3762170b6d4d 208 uint32_t fftLen,
mbed_official 5:3762170b6d4d 209 const q31_t * pCoef)
mbed_official 5:3762170b6d4d 210 {
mbed_official 5:3762170b6d4d 211 uint32_t i, l;
mbed_official 5:3762170b6d4d 212 uint32_t n2, ia;
mbed_official 5:3762170b6d4d 213 q31_t xt, yt, cosVal, sinVal;
mbed_official 5:3762170b6d4d 214 q31_t p0, p1;
mbed_official 5:3762170b6d4d 215
mbed_official 5:3762170b6d4d 216 n2 = fftLen >> 1;
mbed_official 5:3762170b6d4d 217 ia = 0;
mbed_official 5:3762170b6d4d 218 for (i = 0; i < n2; i++)
mbed_official 5:3762170b6d4d 219 {
mbed_official 5:3762170b6d4d 220 cosVal = pCoef[2*ia];
mbed_official 5:3762170b6d4d 221 sinVal = pCoef[2*ia + 1];
mbed_official 5:3762170b6d4d 222 ia++;
mbed_official 5:3762170b6d4d 223
mbed_official 5:3762170b6d4d 224 l = i + n2;
mbed_official 5:3762170b6d4d 225 xt = (pSrc[2 * i] >> 2) - (pSrc[2 * l] >> 2);
mbed_official 5:3762170b6d4d 226 pSrc[2 * i] = (pSrc[2 * i] >> 2) + (pSrc[2 * l] >> 2);
mbed_official 5:3762170b6d4d 227
mbed_official 5:3762170b6d4d 228 yt = (pSrc[2 * i + 1] >> 2) - (pSrc[2 * l + 1] >> 2);
mbed_official 5:3762170b6d4d 229 pSrc[2 * i + 1] = (pSrc[2 * l + 1] >> 2) + (pSrc[2 * i + 1] >> 2);
mbed_official 5:3762170b6d4d 230
mbed_official 5:3762170b6d4d 231 mult_32x32_keep32_R(p0, xt, cosVal);
mbed_official 5:3762170b6d4d 232 mult_32x32_keep32_R(p1, yt, cosVal);
mbed_official 5:3762170b6d4d 233 multSub_32x32_keep32_R(p0, yt, sinVal);
mbed_official 5:3762170b6d4d 234 multAcc_32x32_keep32_R(p1, xt, sinVal);
mbed_official 5:3762170b6d4d 235
mbed_official 5:3762170b6d4d 236 pSrc[2u * l] = p0 << 1;
mbed_official 5:3762170b6d4d 237 pSrc[2u * l + 1u] = p1 << 1;
mbed_official 5:3762170b6d4d 238
mbed_official 5:3762170b6d4d 239 }
mbed_official 5:3762170b6d4d 240
mbed_official 5:3762170b6d4d 241 // first col
mbed_official 5:3762170b6d4d 242 arm_radix4_butterfly_inverse_q31( pSrc, n2, (q31_t*)pCoef, 2u);
mbed_official 5:3762170b6d4d 243 // second col
mbed_official 5:3762170b6d4d 244 arm_radix4_butterfly_inverse_q31( pSrc + fftLen, n2, (q31_t*)pCoef, 2u);
mbed_official 5:3762170b6d4d 245
mbed_official 5:3762170b6d4d 246 for (i = 0; i < fftLen >> 1; i++)
mbed_official 5:3762170b6d4d 247 {
mbed_official 5:3762170b6d4d 248 p0 = pSrc[4*i+0];
mbed_official 5:3762170b6d4d 249 p1 = pSrc[4*i+1];
mbed_official 5:3762170b6d4d 250 xt = pSrc[4*i+2];
mbed_official 5:3762170b6d4d 251 yt = pSrc[4*i+3];
mbed_official 5:3762170b6d4d 252
mbed_official 5:3762170b6d4d 253 p0 <<= 1;
mbed_official 5:3762170b6d4d 254 p1 <<= 1;
mbed_official 5:3762170b6d4d 255 xt <<= 1;
mbed_official 5:3762170b6d4d 256 yt <<= 1;
mbed_official 5:3762170b6d4d 257
mbed_official 5:3762170b6d4d 258 pSrc[4*i+0] = p0;
mbed_official 5:3762170b6d4d 259 pSrc[4*i+1] = p1;
mbed_official 5:3762170b6d4d 260 pSrc[4*i+2] = xt;
mbed_official 5:3762170b6d4d 261 pSrc[4*i+3] = yt;
mbed_official 5:3762170b6d4d 262 }
mbed_official 5:3762170b6d4d 263 }
mbed_official 5:3762170b6d4d 264