1 /* 2 * Copyright (c) 2013 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 #include "dl/api/omxtypes.h" 13 14 void x86SP_FFT_CToC_FC32_Fwd_Radix4_fs( 15 const OMX_F32 *in, 16 OMX_F32 *out, 17 OMX_INT n) { 18 OMX_INT i; 19 OMX_INT n_by_4 = n >> 2; 20 21 // Transform from interleaved format to split format. 22 for (i = 0; i < n; i++) { 23 out[i] = in[i << 1]; 24 out[i + n] = in[(i << 1) + 1]; 25 } 26 27 // As we have already moved data from [in] to [out], 28 // next calculation will be produced in in-place mode. 29 for (i = 0; i < n_by_4; i++) { 30 OMX_F32 *out0 = out + i; 31 OMX_F32 *out1 = out0 + n_by_4; 32 OMX_F32 *out2 = out1 + n_by_4; 33 OMX_F32 *out3 = out2 + n_by_4; 34 35 OMX_FC32 t0; 36 OMX_FC32 t1; 37 OMX_FC32 t2; 38 OMX_FC32 t3; 39 40 // CADD t0, out0, out2 41 t0.Re = out0[0] + out2[0]; 42 t0.Im = out0[n] + out2[n]; 43 44 // CSUB t1, out0, out2 45 t1.Re = out0[0] - out2[0]; 46 t1.Im = out0[n] - out2[n]; 47 48 // CADD t2, out1, out3 49 t2.Re = out1[0] + out3[0]; 50 t2.Im = out1[n] + out3[n]; 51 52 // CSUB t3, out1, out3 53 t3.Re = out1[0] - out3[0]; 54 t3.Im = out1[n] - out3[n]; 55 56 // CADD out0, t0, t2 57 out0[0] = t0.Re + t2.Re; 58 out0[n] = t0.Im + t2.Im; 59 60 // CSUB out2, t0, t2 61 out2[0] = t0.Re - t2.Re; 62 out2[n] = t0.Im - t2.Im; 63 64 // CADD_SUB_X out1, t1, t3 65 out1[0] = t1.Re + t3.Im; 66 out1[n] = t1.Im - t3.Re; 67 68 // CSUB_ADD_X out3, t1, t3 69 out3[0] = t1.Re - t3.Im; 70 out3[n] = t1.Im + t3.Re; 71 } 72 } 73
