1 /* 2 * Copyright (c) 2011 The WebRTC project authors. All Rights Reserved. 3 * 4 * Use of this source code is governed by a BSD-style license 5 * that can be found in the LICENSE file in the root of the source 6 * tree. An additional intellectual property rights grant can be found 7 * in the file PATENTS. All contributing project authors may 8 * be found in the AUTHORS file in the root of the source tree. 9 */ 10 11 /* 12 * WebRtcIsacfix_kTransform.c 13 * 14 * Transform functions 15 * 16 */ 17 18 #include "webrtc/modules/audio_coding/codecs/isac/fix/source/codec.h" 19 #include "webrtc/modules/audio_coding/codecs/isac/fix/source/fft.h" 20 #include "webrtc/modules/audio_coding/codecs/isac/fix/source/settings.h" 21 22 /* Tables are defined in transform_tables.c file or ARM assembly files. */ 23 /* Cosine table 1 in Q14 */ 24 extern const int16_t WebRtcIsacfix_kCosTab1[FRAMESAMPLES/2]; 25 /* Sine table 1 in Q14 */ 26 extern const int16_t WebRtcIsacfix_kSinTab1[FRAMESAMPLES/2]; 27 /* Sine table 2 in Q14 */ 28 extern const int16_t WebRtcIsacfix_kSinTab2[FRAMESAMPLES/4]; 29 30 void WebRtcIsacfix_Time2SpecC(int16_t *inre1Q9, 31 int16_t *inre2Q9, 32 int16_t *outreQ7, 33 int16_t *outimQ7) 34 { 35 36 int k; 37 int32_t tmpreQ16[FRAMESAMPLES/2], tmpimQ16[FRAMESAMPLES/2]; 38 int16_t tmp1rQ14, tmp1iQ14; 39 int32_t xrQ16, xiQ16, yrQ16, yiQ16; 40 int32_t v1Q16, v2Q16; 41 int16_t factQ19, sh; 42 43 /* Multiply with complex exponentials and combine into one complex vector */ 44 factQ19 = 16921; // 0.5/sqrt(240) in Q19 is round(.5/sqrt(240)*(2^19)) = 16921 45 for (k = 0; k < FRAMESAMPLES/2; k++) { 46 tmp1rQ14 = WebRtcIsacfix_kCosTab1[k]; 47 tmp1iQ14 = WebRtcIsacfix_kSinTab1[k]; 48 xrQ16 = WEBRTC_SPL_RSHIFT_W32(WEBRTC_SPL_MUL_16_16(tmp1rQ14, inre1Q9[k]) + WEBRTC_SPL_MUL_16_16(tmp1iQ14, inre2Q9[k]), 7); 49 xiQ16 = WEBRTC_SPL_RSHIFT_W32(WEBRTC_SPL_MUL_16_16(tmp1rQ14, inre2Q9[k]) - WEBRTC_SPL_MUL_16_16(tmp1iQ14, inre1Q9[k]), 7); 50 tmpreQ16[k] = WEBRTC_SPL_RSHIFT_W32(WEBRTC_SPL_MUL_16_32_RSFT16(factQ19, xrQ16)+4, 3); // (Q16*Q19>>16)>>3 = Q16 51 tmpimQ16[k] = WEBRTC_SPL_RSHIFT_W32(WEBRTC_SPL_MUL_16_32_RSFT16(factQ19, xiQ16)+4, 3); // (Q16*Q19>>16)>>3 = Q16 52 } 53 54 55 xrQ16 = WebRtcSpl_MaxAbsValueW32(tmpreQ16, FRAMESAMPLES/2); 56 yrQ16 = WebRtcSpl_MaxAbsValueW32(tmpimQ16, FRAMESAMPLES/2); 57 if (yrQ16>xrQ16) { 58 xrQ16 = yrQ16; 59 } 60 61 sh = WebRtcSpl_NormW32(xrQ16); 62 sh = sh-24; //if sh becomes >=0, then we should shift sh steps to the left, and the domain will become Q(16+sh) 63 //if sh becomes <0, then we should shift -sh steps to the right, and the domain will become Q(16+sh) 64 65 //"Fastest" vectors 66 if (sh>=0) { 67 for (k=0; k<FRAMESAMPLES/2; k++) { 68 inre1Q9[k] = (int16_t) WEBRTC_SPL_LSHIFT_W32(tmpreQ16[k], sh); //Q(16+sh) 69 inre2Q9[k] = (int16_t) WEBRTC_SPL_LSHIFT_W32(tmpimQ16[k], sh); //Q(16+sh) 70 } 71 } else { 72 int32_t round = WEBRTC_SPL_LSHIFT_W32((int32_t)1, -sh-1); 73 for (k=0; k<FRAMESAMPLES/2; k++) { 74 inre1Q9[k] = (int16_t) WEBRTC_SPL_RSHIFT_W32(tmpreQ16[k]+round, -sh); //Q(16+sh) 75 inre2Q9[k] = (int16_t) WEBRTC_SPL_RSHIFT_W32(tmpimQ16[k]+round, -sh); //Q(16+sh) 76 } 77 } 78 79 /* Get DFT */ 80 WebRtcIsacfix_FftRadix16Fastest(inre1Q9, inre2Q9, -1); // real call 81 82 //"Fastest" vectors 83 if (sh>=0) { 84 for (k=0; k<FRAMESAMPLES/2; k++) { 85 tmpreQ16[k] = WEBRTC_SPL_RSHIFT_W32((int32_t)inre1Q9[k], sh); //Q(16+sh) -> Q16 86 tmpimQ16[k] = WEBRTC_SPL_RSHIFT_W32((int32_t)inre2Q9[k], sh); //Q(16+sh) -> Q16 87 } 88 } else { 89 for (k=0; k<FRAMESAMPLES/2; k++) { 90 tmpreQ16[k] = WEBRTC_SPL_LSHIFT_W32((int32_t)inre1Q9[k], -sh); //Q(16+sh) -> Q16 91 tmpimQ16[k] = WEBRTC_SPL_LSHIFT_W32((int32_t)inre2Q9[k], -sh); //Q(16+sh) -> Q16 92 } 93 } 94 95 96 /* Use symmetry to separate into two complex vectors and center frames in time around zero */ 97 for (k = 0; k < FRAMESAMPLES/4; k++) { 98 xrQ16 = tmpreQ16[k] + tmpreQ16[FRAMESAMPLES/2 - 1 - k]; 99 yiQ16 = -tmpreQ16[k] + tmpreQ16[FRAMESAMPLES/2 - 1 - k]; 100 xiQ16 = tmpimQ16[k] - tmpimQ16[FRAMESAMPLES/2 - 1 - k]; 101 yrQ16 = tmpimQ16[k] + tmpimQ16[FRAMESAMPLES/2 - 1 - k]; 102 tmp1rQ14 = -WebRtcIsacfix_kSinTab2[FRAMESAMPLES/4 - 1 - k]; 103 tmp1iQ14 = WebRtcIsacfix_kSinTab2[k]; 104 v1Q16 = WEBRTC_SPL_MUL_16_32_RSFT14(tmp1rQ14, xrQ16) - WEBRTC_SPL_MUL_16_32_RSFT14(tmp1iQ14, xiQ16); 105 v2Q16 = WEBRTC_SPL_MUL_16_32_RSFT14(tmp1iQ14, xrQ16) + WEBRTC_SPL_MUL_16_32_RSFT14(tmp1rQ14, xiQ16); 106 outreQ7[k] = (int16_t) WEBRTC_SPL_RSHIFT_W32(v1Q16, 9); 107 outimQ7[k] = (int16_t) WEBRTC_SPL_RSHIFT_W32(v2Q16, 9); 108 v1Q16 = -WEBRTC_SPL_MUL_16_32_RSFT14(tmp1iQ14, yrQ16) - WEBRTC_SPL_MUL_16_32_RSFT14(tmp1rQ14, yiQ16); 109 v2Q16 = -WEBRTC_SPL_MUL_16_32_RSFT14(tmp1rQ14, yrQ16) + WEBRTC_SPL_MUL_16_32_RSFT14(tmp1iQ14, yiQ16); 110 outreQ7[FRAMESAMPLES/2 - 1 - k] = (int16_t)WEBRTC_SPL_RSHIFT_W32(v1Q16, 9); //CalcLrIntQ(v1Q16, 9); 111 outimQ7[FRAMESAMPLES/2 - 1 - k] = (int16_t)WEBRTC_SPL_RSHIFT_W32(v2Q16, 9); //CalcLrIntQ(v2Q16, 9); 112 113 } 114 } 115 116 117 void WebRtcIsacfix_Spec2TimeC(int16_t *inreQ7, int16_t *inimQ7, int32_t *outre1Q16, int32_t *outre2Q16) 118 { 119 120 int k; 121 int16_t tmp1rQ14, tmp1iQ14; 122 int32_t xrQ16, xiQ16, yrQ16, yiQ16; 123 int32_t tmpInRe, tmpInIm, tmpInRe2, tmpInIm2; 124 int16_t factQ11; 125 int16_t sh; 126 127 for (k = 0; k < FRAMESAMPLES/4; k++) { 128 /* Move zero in time to beginning of frames */ 129 tmp1rQ14 = -WebRtcIsacfix_kSinTab2[FRAMESAMPLES/4 - 1 - k]; 130 tmp1iQ14 = WebRtcIsacfix_kSinTab2[k]; 131 132 tmpInRe = WEBRTC_SPL_LSHIFT_W32((int32_t) inreQ7[k], 9); // Q7 -> Q16 133 tmpInIm = WEBRTC_SPL_LSHIFT_W32((int32_t) inimQ7[k], 9); // Q7 -> Q16 134 tmpInRe2 = WEBRTC_SPL_LSHIFT_W32((int32_t) inreQ7[FRAMESAMPLES/2 - 1 - k], 9); // Q7 -> Q16 135 tmpInIm2 = WEBRTC_SPL_LSHIFT_W32((int32_t) inimQ7[FRAMESAMPLES/2 - 1 - k], 9); // Q7 -> Q16 136 137 xrQ16 = WEBRTC_SPL_MUL_16_32_RSFT14(tmp1rQ14, tmpInRe) + WEBRTC_SPL_MUL_16_32_RSFT14(tmp1iQ14, tmpInIm); 138 xiQ16 = WEBRTC_SPL_MUL_16_32_RSFT14(tmp1rQ14, tmpInIm) - WEBRTC_SPL_MUL_16_32_RSFT14(tmp1iQ14, tmpInRe); 139 yrQ16 = -WEBRTC_SPL_MUL_16_32_RSFT14(tmp1rQ14, tmpInIm2) - WEBRTC_SPL_MUL_16_32_RSFT14(tmp1iQ14, tmpInRe2); 140 yiQ16 = -WEBRTC_SPL_MUL_16_32_RSFT14(tmp1rQ14, tmpInRe2) + WEBRTC_SPL_MUL_16_32_RSFT14(tmp1iQ14, tmpInIm2); 141 142 /* Combine into one vector, z = x + j * y */ 143 outre1Q16[k] = xrQ16 - yiQ16; 144 outre1Q16[FRAMESAMPLES/2 - 1 - k] = xrQ16 + yiQ16; 145 outre2Q16[k] = xiQ16 + yrQ16; 146 outre2Q16[FRAMESAMPLES/2 - 1 - k] = -xiQ16 + yrQ16; 147 } 148 149 /* Get IDFT */ 150 tmpInRe = WebRtcSpl_MaxAbsValueW32(outre1Q16, 240); 151 tmpInIm = WebRtcSpl_MaxAbsValueW32(outre2Q16, 240); 152 if (tmpInIm>tmpInRe) { 153 tmpInRe = tmpInIm; 154 } 155 156 sh = WebRtcSpl_NormW32(tmpInRe); 157 sh = sh-24; //if sh becomes >=0, then we should shift sh steps to the left, and the domain will become Q(16+sh) 158 //if sh becomes <0, then we should shift -sh steps to the right, and the domain will become Q(16+sh) 159 160 //"Fastest" vectors 161 if (sh>=0) { 162 for (k=0; k<240; k++) { 163 inreQ7[k] = (int16_t) WEBRTC_SPL_LSHIFT_W32(outre1Q16[k], sh); //Q(16+sh) 164 inimQ7[k] = (int16_t) WEBRTC_SPL_LSHIFT_W32(outre2Q16[k], sh); //Q(16+sh) 165 } 166 } else { 167 int32_t round = WEBRTC_SPL_LSHIFT_W32((int32_t)1, -sh-1); 168 for (k=0; k<240; k++) { 169 inreQ7[k] = (int16_t) WEBRTC_SPL_RSHIFT_W32(outre1Q16[k]+round, -sh); //Q(16+sh) 170 inimQ7[k] = (int16_t) WEBRTC_SPL_RSHIFT_W32(outre2Q16[k]+round, -sh); //Q(16+sh) 171 } 172 } 173 174 WebRtcIsacfix_FftRadix16Fastest(inreQ7, inimQ7, 1); // real call 175 176 //"Fastest" vectors 177 if (sh>=0) { 178 for (k=0; k<240; k++) { 179 outre1Q16[k] = WEBRTC_SPL_RSHIFT_W32((int32_t)inreQ7[k], sh); //Q(16+sh) -> Q16 180 outre2Q16[k] = WEBRTC_SPL_RSHIFT_W32((int32_t)inimQ7[k], sh); //Q(16+sh) -> Q16 181 } 182 } else { 183 for (k=0; k<240; k++) { 184 outre1Q16[k] = WEBRTC_SPL_LSHIFT_W32((int32_t)inreQ7[k], -sh); //Q(16+sh) -> Q16 185 outre2Q16[k] = WEBRTC_SPL_LSHIFT_W32((int32_t)inimQ7[k], -sh); //Q(16+sh) -> Q16 186 } 187 } 188 189 /* Divide through by the normalizing constant: */ 190 /* scale all values with 1/240, i.e. with 273 in Q16 */ 191 /* 273/65536 ~= 0.0041656 */ 192 /* 1/240 ~= 0.0041666 */ 193 for (k=0; k<240; k++) { 194 outre1Q16[k] = WEBRTC_SPL_MUL_16_32_RSFT16(273, outre1Q16[k]); 195 outre2Q16[k] = WEBRTC_SPL_MUL_16_32_RSFT16(273, outre2Q16[k]); 196 } 197 198 /* Demodulate and separate */ 199 factQ11 = 31727; // sqrt(240) in Q11 is round(15.49193338482967*2048) = 31727 200 for (k = 0; k < FRAMESAMPLES/2; k++) { 201 tmp1rQ14 = WebRtcIsacfix_kCosTab1[k]; 202 tmp1iQ14 = WebRtcIsacfix_kSinTab1[k]; 203 xrQ16 = WEBRTC_SPL_MUL_16_32_RSFT14(tmp1rQ14, outre1Q16[k]) - WEBRTC_SPL_MUL_16_32_RSFT14(tmp1iQ14, outre2Q16[k]); 204 xiQ16 = WEBRTC_SPL_MUL_16_32_RSFT14(tmp1rQ14, outre2Q16[k]) + WEBRTC_SPL_MUL_16_32_RSFT14(tmp1iQ14, outre1Q16[k]); 205 xrQ16 = WEBRTC_SPL_MUL_16_32_RSFT11(factQ11, xrQ16); 206 xiQ16 = WEBRTC_SPL_MUL_16_32_RSFT11(factQ11, xiQ16); 207 outre2Q16[k] = xiQ16; 208 outre1Q16[k] = xrQ16; 209 } 210 } 211
