annotate libtwamr/r_fft.c @ 478:936a08cc73ce

doc/AMR-library-API: describe the decoder
author Mychaela Falconia <falcon@freecalypso.org>
date Sun, 19 May 2024 21:32:31 +0000
parents 810ac4b99025
children
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810ac4b99025 libtwamr: integrate VAD2 r_fft.c
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1 /*
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2 *****************************************************************************
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3 *
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4 * GSM AMR-NB speech codec R98 Version 7.6.0 December 12, 2001
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5 * R99 Version 3.3.0
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6 * REL-4 Version 4.1.0
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7 *
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8 *****************************************************************************
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9 *
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10 * File : r_fft.c
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11 * Purpose : Fast Fourier Transform (FFT) algorithm
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12 *
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13 *****************************************************************************
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14 */
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15
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16 /*****************************************************************
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17 *
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18 * This is an implementation of decimation-in-time FFT algorithm for
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19 * real sequences. The techniques used here can be found in several
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20 * books, e.g., i) Proakis and Manolakis, "Digital Signal Processing",
810ac4b99025 libtwamr: integrate VAD2 r_fft.c
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21 * 2nd Edition, Chapter 9, and ii) W.H. Press et. al., "Numerical
810ac4b99025 libtwamr: integrate VAD2 r_fft.c
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22 * Recipes in C", 2nd Ediiton, Chapter 12.
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23 *
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24 * Input - There is one input to this function:
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25 *
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26 * 1) An integer pointer to the input data array
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27 *
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28 * Output - There is no return value.
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29 * The input data are replaced with transformed data. If the
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30 * input is a real time domain sequence, it is replaced with
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31 * the complex FFT for positive frequencies. The FFT value
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32 * for DC and the foldover frequency are combined to form the
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33 * first complex number in the array. The remaining complex
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34 * numbers correspond to increasing frequencies. If the input
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35 * is a complex frequency domain sequence arranged as above,
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36 * it is replaced with the corresponding time domain sequence.
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37 *
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38 * Notes:
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39 *
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40 * 1) This function is designed to be a part of a VAD
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41 * algorithm that requires 128-point FFT of real
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42 * sequences. This is achieved here through a 64-point
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43 * complex FFT. Consequently, the FFT size information is
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44 * not transmitted explicitly. However, some flexibility
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45 * is provided in the function to change the size of the
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46 * FFT by specifying the size information through "define"
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47 * statements.
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48 *
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49 * 2) The values of the complex sinusoids used in the FFT
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50 * algorithm are stored in a ROM table.
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51 *
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52 * 3) In the c_fft function, the FFT values are divided by
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53 * 2 after each stage of computation thus dividing the
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54 * final FFT values by 64. This is somewhat different
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55 * from the usual definition of FFT where the factor 1/N,
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56 * i.e., 1/64, used for the IFFT and not the FFT. No factor
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57 * is used in the r_fft function.
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58 *
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59 *****************************************************************/
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60
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61 #include "tw_amr.h"
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62 #include "namespace.h"
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63 #include "typedef.h"
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64 #include "cnst.h"
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65 #include "basic_op.h"
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66 #include "oper_32b.h"
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67 #include "no_count.h"
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68 #include "vad2.h"
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69
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70 #define SIZE 128
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71 #define SIZE_BY_TWO 64
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72 #define NUM_STAGE 6
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73 #define TRUE 1
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74 #define FALSE 0
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75
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76 static const Word16 phs_tbl[] =
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77 {
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78
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79 32767, 0, 32729, -1608, 32610, -3212, 32413, -4808,
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80 32138, -6393, 31786, -7962, 31357, -9512, 30853, -11039,
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81 30274, -12540, 29622, -14010, 28899, -15447, 28106, -16846,
810ac4b99025 libtwamr: integrate VAD2 r_fft.c
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82 27246, -18205, 26320, -19520, 25330, -20788, 24279, -22006,
810ac4b99025 libtwamr: integrate VAD2 r_fft.c
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83 23170, -23170, 22006, -24279, 20788, -25330, 19520, -26320,
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84 18205, -27246, 16846, -28106, 15447, -28899, 14010, -29622,
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85 12540, -30274, 11039, -30853, 9512, -31357, 7962, -31786,
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86 6393, -32138, 4808, -32413, 3212, -32610, 1608, -32729,
810ac4b99025 libtwamr: integrate VAD2 r_fft.c
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87 0, -32768, -1608, -32729, -3212, -32610, -4808, -32413,
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88 -6393, -32138, -7962, -31786, -9512, -31357, -11039, -30853,
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89 -12540, -30274, -14010, -29622, -15447, -28899, -16846, -28106,
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90 -18205, -27246, -19520, -26320, -20788, -25330, -22006, -24279,
810ac4b99025 libtwamr: integrate VAD2 r_fft.c
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91 -23170, -23170, -24279, -22006, -25330, -20788, -26320, -19520,
810ac4b99025 libtwamr: integrate VAD2 r_fft.c
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92 -27246, -18205, -28106, -16846, -28899, -15447, -29622, -14010,
810ac4b99025 libtwamr: integrate VAD2 r_fft.c
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93 -30274, -12540, -30853, -11039, -31357, -9512, -31786, -7962,
810ac4b99025 libtwamr: integrate VAD2 r_fft.c
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94 -32138, -6393, -32413, -4808, -32610, -3212, -32729, -1608
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95
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96 };
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97
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98 static const Word16 ii_table[] =
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99 {SIZE / 2, SIZE / 4, SIZE / 8, SIZE / 16, SIZE / 32, SIZE / 64};
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100
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101 /* FFT function for complex sequences */
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102
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103 /*
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104 * The decimation-in-time complex FFT is implemented below.
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105 * The input complex numbers are presented as real part followed by
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106 * imaginary part for each sample. The counters are therefore
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107 * incremented by two to access the complex valued samples.
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108 */
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109
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110 static void c_fft(Word16 * farray_ptr)
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111 {
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112
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113 Word16 i, j, k, ii, jj, kk, ji, kj, ii2;
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114 Word32 ftmp, ftmp_real, ftmp_imag;
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115 Word16 tmp, tmp1, tmp2;
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116
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117 /* Rearrange the input array in bit reversed order */
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118 for (i = 0, j = 0; i < SIZE - 2; i = i + 2)
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119 { test();
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120 if (sub(j, i) > 0)
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121 {
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122 ftmp = *(farray_ptr + i); move16();
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123 *(farray_ptr + i) = *(farray_ptr + j); move16();
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124 *(farray_ptr + j) = ftmp; move16();
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Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
125
810ac4b99025 libtwamr: integrate VAD2 r_fft.c
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
126 ftmp = *(farray_ptr + i + 1); move16();
810ac4b99025 libtwamr: integrate VAD2 r_fft.c
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
127 *(farray_ptr + i + 1) = *(farray_ptr + j + 1); move16();
810ac4b99025 libtwamr: integrate VAD2 r_fft.c
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
128 *(farray_ptr + j + 1) = ftmp; move16();
810ac4b99025 libtwamr: integrate VAD2 r_fft.c
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
129 }
810ac4b99025 libtwamr: integrate VAD2 r_fft.c
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
130
810ac4b99025 libtwamr: integrate VAD2 r_fft.c
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
131 k = SIZE_BY_TWO; move16();
810ac4b99025 libtwamr: integrate VAD2 r_fft.c
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
132 test();
810ac4b99025 libtwamr: integrate VAD2 r_fft.c
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
133 while (sub(j, k) >= 0)
810ac4b99025 libtwamr: integrate VAD2 r_fft.c
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
134 {
810ac4b99025 libtwamr: integrate VAD2 r_fft.c
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
135 j = sub(j, k);
810ac4b99025 libtwamr: integrate VAD2 r_fft.c
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
136 k = shr(k, 1);
810ac4b99025 libtwamr: integrate VAD2 r_fft.c
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
137 }
810ac4b99025 libtwamr: integrate VAD2 r_fft.c
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
138 j = add(j, k);
810ac4b99025 libtwamr: integrate VAD2 r_fft.c
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
139 }
810ac4b99025 libtwamr: integrate VAD2 r_fft.c
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
140
810ac4b99025 libtwamr: integrate VAD2 r_fft.c
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
141 /* The FFT part */
810ac4b99025 libtwamr: integrate VAD2 r_fft.c
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
142 for (i = 0; i < NUM_STAGE; i++)
810ac4b99025 libtwamr: integrate VAD2 r_fft.c
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
143 { /* i is stage counter */
810ac4b99025 libtwamr: integrate VAD2 r_fft.c
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
144 jj = shl(2, i); /* FFT size */
810ac4b99025 libtwamr: integrate VAD2 r_fft.c
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
145 kk = shl(jj, 1); /* 2 * FFT size */
810ac4b99025 libtwamr: integrate VAD2 r_fft.c
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
146 ii = ii_table[i]; /* 2 * number of FFT's */ move16();
810ac4b99025 libtwamr: integrate VAD2 r_fft.c
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
147 ii2 = shl(ii, 1);
810ac4b99025 libtwamr: integrate VAD2 r_fft.c
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
148 ji = 0; /* ji is phase table index */ move16();
810ac4b99025 libtwamr: integrate VAD2 r_fft.c
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
149
810ac4b99025 libtwamr: integrate VAD2 r_fft.c
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
150 for (j = 0; j < jj; j = j + 2)
810ac4b99025 libtwamr: integrate VAD2 r_fft.c
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
151 { /* j is sample counter */
810ac4b99025 libtwamr: integrate VAD2 r_fft.c
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
152
810ac4b99025 libtwamr: integrate VAD2 r_fft.c
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
153 for (k = j; k < SIZE; k = k + kk)
810ac4b99025 libtwamr: integrate VAD2 r_fft.c
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
154 { /* k is butterfly top */
810ac4b99025 libtwamr: integrate VAD2 r_fft.c
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
155 kj = add(k, jj); /* kj is butterfly bottom */
810ac4b99025 libtwamr: integrate VAD2 r_fft.c
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
156
810ac4b99025 libtwamr: integrate VAD2 r_fft.c
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
157 /* Butterfly computations */
810ac4b99025 libtwamr: integrate VAD2 r_fft.c
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
158 ftmp_real = L_mult(*(farray_ptr + kj), phs_tbl[ji]);
810ac4b99025 libtwamr: integrate VAD2 r_fft.c
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
159 ftmp_real = L_msu(ftmp_real, *(farray_ptr + kj + 1), phs_tbl[ji + 1]);
810ac4b99025 libtwamr: integrate VAD2 r_fft.c
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
160
810ac4b99025 libtwamr: integrate VAD2 r_fft.c
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
161 ftmp_imag = L_mult(*(farray_ptr + kj + 1), phs_tbl[ji]);
810ac4b99025 libtwamr: integrate VAD2 r_fft.c
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
162 ftmp_imag = L_mac(ftmp_imag, *(farray_ptr + kj), phs_tbl[ji + 1]);
810ac4b99025 libtwamr: integrate VAD2 r_fft.c
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
163
810ac4b99025 libtwamr: integrate VAD2 r_fft.c
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
164 tmp1 = round(ftmp_real);
810ac4b99025 libtwamr: integrate VAD2 r_fft.c
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
165 tmp2 = round(ftmp_imag);
810ac4b99025 libtwamr: integrate VAD2 r_fft.c
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
166
810ac4b99025 libtwamr: integrate VAD2 r_fft.c
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
167 tmp = sub(*(farray_ptr + k), tmp1);
810ac4b99025 libtwamr: integrate VAD2 r_fft.c
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
168 *(farray_ptr + kj) = shr(tmp, 1); move16();
810ac4b99025 libtwamr: integrate VAD2 r_fft.c
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
169
810ac4b99025 libtwamr: integrate VAD2 r_fft.c
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
170 tmp = sub(*(farray_ptr + k + 1), tmp2);
810ac4b99025 libtwamr: integrate VAD2 r_fft.c
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
171 *(farray_ptr + kj + 1) = shr(tmp, 1); move16();
810ac4b99025 libtwamr: integrate VAD2 r_fft.c
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
172
810ac4b99025 libtwamr: integrate VAD2 r_fft.c
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
173 tmp = add(*(farray_ptr + k), tmp1);
810ac4b99025 libtwamr: integrate VAD2 r_fft.c
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
174 *(farray_ptr + k) = shr(tmp, 1); move16();
810ac4b99025 libtwamr: integrate VAD2 r_fft.c
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
175
810ac4b99025 libtwamr: integrate VAD2 r_fft.c
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
176 tmp = add(*(farray_ptr + k + 1), tmp2);
810ac4b99025 libtwamr: integrate VAD2 r_fft.c
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
177 *(farray_ptr + k + 1) = shr(tmp, 1); move16();
810ac4b99025 libtwamr: integrate VAD2 r_fft.c
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
178 }
810ac4b99025 libtwamr: integrate VAD2 r_fft.c
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
179
810ac4b99025 libtwamr: integrate VAD2 r_fft.c
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
180 ji = add(ji, ii2);
810ac4b99025 libtwamr: integrate VAD2 r_fft.c
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
181 }
810ac4b99025 libtwamr: integrate VAD2 r_fft.c
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
182 }
810ac4b99025 libtwamr: integrate VAD2 r_fft.c
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
183 } /* end of c_fft () */
810ac4b99025 libtwamr: integrate VAD2 r_fft.c
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
184
810ac4b99025 libtwamr: integrate VAD2 r_fft.c
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
185
810ac4b99025 libtwamr: integrate VAD2 r_fft.c
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
186
810ac4b99025 libtwamr: integrate VAD2 r_fft.c
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
187 void r_fft(Word16 * farray_ptr)
810ac4b99025 libtwamr: integrate VAD2 r_fft.c
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
188 {
810ac4b99025 libtwamr: integrate VAD2 r_fft.c
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
189
810ac4b99025 libtwamr: integrate VAD2 r_fft.c
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
190 Word16 ftmp1_real, ftmp1_imag, ftmp2_real, ftmp2_imag;
810ac4b99025 libtwamr: integrate VAD2 r_fft.c
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
191 Word32 Lftmp1_real, Lftmp1_imag;
810ac4b99025 libtwamr: integrate VAD2 r_fft.c
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
192 Word16 i, j;
810ac4b99025 libtwamr: integrate VAD2 r_fft.c
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
193 Word32 Ltmp1;
810ac4b99025 libtwamr: integrate VAD2 r_fft.c
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
194
810ac4b99025 libtwamr: integrate VAD2 r_fft.c
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
195 /* Perform the complex FFT */
810ac4b99025 libtwamr: integrate VAD2 r_fft.c
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
196 c_fft(farray_ptr);
810ac4b99025 libtwamr: integrate VAD2 r_fft.c
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
197
810ac4b99025 libtwamr: integrate VAD2 r_fft.c
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
198 /* First, handle the DC and foldover frequencies */
810ac4b99025 libtwamr: integrate VAD2 r_fft.c
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
199 ftmp1_real = *farray_ptr; move16();
810ac4b99025 libtwamr: integrate VAD2 r_fft.c
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
200 ftmp2_real = *(farray_ptr + 1); move16();
810ac4b99025 libtwamr: integrate VAD2 r_fft.c
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
201 *farray_ptr = add(ftmp1_real, ftmp2_real); move16();
810ac4b99025 libtwamr: integrate VAD2 r_fft.c
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
202 *(farray_ptr + 1) = sub(ftmp1_real, ftmp2_real); move16();
810ac4b99025 libtwamr: integrate VAD2 r_fft.c
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
203
810ac4b99025 libtwamr: integrate VAD2 r_fft.c
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
204 /* Now, handle the remaining positive frequencies */
810ac4b99025 libtwamr: integrate VAD2 r_fft.c
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
205 for (i = 2, j = SIZE - i; i <= SIZE_BY_TWO; i = i + 2, j = SIZE - i)
810ac4b99025 libtwamr: integrate VAD2 r_fft.c
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
206 {
810ac4b99025 libtwamr: integrate VAD2 r_fft.c
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
207 ftmp1_real = add(*(farray_ptr + i), *(farray_ptr + j));
810ac4b99025 libtwamr: integrate VAD2 r_fft.c
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
208 ftmp1_imag = sub(*(farray_ptr + i + 1), *(farray_ptr + j + 1));
810ac4b99025 libtwamr: integrate VAD2 r_fft.c
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
209 ftmp2_real = add(*(farray_ptr + i + 1), *(farray_ptr + j + 1));
810ac4b99025 libtwamr: integrate VAD2 r_fft.c
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
210 ftmp2_imag = sub(*(farray_ptr + j), *(farray_ptr + i));
810ac4b99025 libtwamr: integrate VAD2 r_fft.c
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
211
810ac4b99025 libtwamr: integrate VAD2 r_fft.c
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
212 Lftmp1_real = L_deposit_h(ftmp1_real);
810ac4b99025 libtwamr: integrate VAD2 r_fft.c
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
213 Lftmp1_imag = L_deposit_h(ftmp1_imag);
810ac4b99025 libtwamr: integrate VAD2 r_fft.c
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
214
810ac4b99025 libtwamr: integrate VAD2 r_fft.c
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
215 Ltmp1 = L_mac(Lftmp1_real, ftmp2_real, phs_tbl[i]);
810ac4b99025 libtwamr: integrate VAD2 r_fft.c
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
216 Ltmp1 = L_msu(Ltmp1, ftmp2_imag, phs_tbl[i + 1]);
810ac4b99025 libtwamr: integrate VAD2 r_fft.c
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
217 *(farray_ptr + i) = round(L_shr(Ltmp1, 1)); move16();
810ac4b99025 libtwamr: integrate VAD2 r_fft.c
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
218
810ac4b99025 libtwamr: integrate VAD2 r_fft.c
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
219 Ltmp1 = L_mac(Lftmp1_imag, ftmp2_imag, phs_tbl[i]);
810ac4b99025 libtwamr: integrate VAD2 r_fft.c
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
220 Ltmp1 = L_mac(Ltmp1, ftmp2_real, phs_tbl[i + 1]);
810ac4b99025 libtwamr: integrate VAD2 r_fft.c
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
221 *(farray_ptr + i + 1) = round(L_shr(Ltmp1, 1)); move16();
810ac4b99025 libtwamr: integrate VAD2 r_fft.c
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
222
810ac4b99025 libtwamr: integrate VAD2 r_fft.c
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
223 Ltmp1 = L_mac(Lftmp1_real, ftmp2_real, phs_tbl[j]);
810ac4b99025 libtwamr: integrate VAD2 r_fft.c
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
224 Ltmp1 = L_mac(Ltmp1, ftmp2_imag, phs_tbl[j + 1]);
810ac4b99025 libtwamr: integrate VAD2 r_fft.c
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
225 *(farray_ptr + j) = round(L_shr(Ltmp1, 1)); move16();
810ac4b99025 libtwamr: integrate VAD2 r_fft.c
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
226
810ac4b99025 libtwamr: integrate VAD2 r_fft.c
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
227 Ltmp1 = L_negate(Lftmp1_imag);
810ac4b99025 libtwamr: integrate VAD2 r_fft.c
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
228 Ltmp1 = L_msu(Ltmp1, ftmp2_imag, phs_tbl[j]);
810ac4b99025 libtwamr: integrate VAD2 r_fft.c
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
229 Ltmp1 = L_mac(Ltmp1, ftmp2_real, phs_tbl[j + 1]);
810ac4b99025 libtwamr: integrate VAD2 r_fft.c
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
230 *(farray_ptr + j + 1) = round(L_shr(Ltmp1, 1)); move16();
810ac4b99025 libtwamr: integrate VAD2 r_fft.c
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
231
810ac4b99025 libtwamr: integrate VAD2 r_fft.c
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
232 }
810ac4b99025 libtwamr: integrate VAD2 r_fft.c
Mychaela Falconia <falcon@freecalypso.org>
parents:
diff changeset
233 } /* end r_fft () */