1mlib_SignalFFT_2(3MLIB) mediaLib Library Functions mlib_SignalFFT_2(3MLIB)
2
6 mlib_SignalFFT_2, mlib_SignalFFT_2_S16_S16, mlib_SignalFFT_2_S16C_S16C,
7 mlib_SignalFFT_2_S16C_S16, mlib_SignalFFT_2_S16, mlib_SignalFFT_2_S16C,
8 mlib_SignalFFT_2_F32_F32, mlib_SignalFFT_2_F32C_F32C, mlib_Sig‐
9 nalFFT_2_F32C_F32, mlib_SignalFFT_2_F32, mlib_SignalFFT_2_F32C,
10 mlib_SignalFFT_2_D64_D64, mlib_SignalFFT_2_D64C_D64C, mlib_Sig‐
11 nalFFT_2_D64C_D64, mlib_SignalFFT_2_D64, mlib_SignalFFT_2_D64C - signal
12 Fast Fourier Transform (FFT)
13
15 cc [ flag... ] file... -lmlib [ library... ]
16 #include <mlib.h>
17 mlib_status mlib_SignalFFT_2_S16_S16(mlib_s16 *dstr, mlib_s16 *dsti,
19 const mlib_s16 *srcr, const mlib_s16 *srci, mlib_s32 order);
20 mlib_status mlib_SignalFFT_2_S16C_S16C(mlib_s16 *dstc,
23 const mlib_s16 *srcc,
24 mlib_s32 order);
25 mlib_status mlib_SignalFFT_2_S16C_S16(mlib_s16 *dstc, const mlib_s16 *srcr,
28 mlib_s32 order);
29 mlib_status mlib_SignalFFT_2_S16(mlib_s16 *srcdstr, mlib_s16 *srcdsti,
32 mlib_s32 order);
33 mlib_status mlib_SignalFFT_2_S16C(mlib_s16 *srcdstc, mlib_s32 order);
36 mlib_status mlib_SignalFFT_2_F32_F32(mlib_f32 *dstr,
39 mlib_f32 *dsti,const mlib_f32 *srcr,
40 const mlib_f32 *srci,
41 mlib_s32 order);
42 mlib_status mlib_SignalFFT_2_F32C_F32C(mlib_f32 *dstc,
45 const mlib_f32 *srcc,
46 mlib_s32 order);
47 mlib_status mlib_SignalFFT_2_F32C_F32(mlib_f32 *dstc, const mlib_f32 *srcr,
50 mlib_s32 order);
51 mlib_status mlib_SignalFFT_2_F32(mlib_f32 *srcdstr, mlib_f32 *srcdsti,
54 mlib_s32 order);
55 mlib_status mlib_SignalFFT_2_F32C(mlib_f32 *srcdstc, mlib_s32 order);
58 mlib_status mlib_SignalFFT_2_D64_D64(mlib_d64 *dstr, mlib_d64 *dsti,
61 const mlib_d64 *srcr, const mlib_d64 *srci, mlib_s32 order);
62 mlib_status mlib_SignalFFT_2_D64C_D64C(mlib_d64 *dstc,
65 const mlib_d64 *srcc,mlib_s32 order);
66 mlib_status mlib_SignalFFT_2_D64C_D64(mlib_d64 *dstc, const mlib_d64 *srcr,
69 mlib_s32 order);
70 mlib_status mlib_SignalFFT_2_D64(mlib_d64 *srcdstr, mlib_d64 *srcdsti,
73 mlib_s32 order);
74 mlib_status mlib_SignalFFT_2_D64C(mlib_d64 *srcdstc, mlib_s32 order);
77
80 Each of the functions in this group performs Fast Fourier Transform
81 (FFT).
82 The following equation is used for forward FFT:
85 1 N-1
87 dst[k] = ---- SUM {src[n] * exp(-j2*PI*n*k/N)}
88 C1 n=0
89 and the following equation is used for inverse FFT (IFFT):
93 1 N-1
95 dst[n] = ---- SUM {src[k] * exp(j2*PI*n*k/N)}
96 C2 k=0
97 where
101 k = 0, 1, ..., (N - 1)
103 n = 0, 1, ..., (N - 1)
104 N = 2**order
105 The signal FFT/IFFT functions can be categorized into four groups
109 according to the ScaleMode in the function names in the following form:
110 mlib_Signal[FFT|IFFT]_ScaleMode_OutType_InType_OpMode()
112 mlib_Signal[FFT|IFFT]_ScaleMode_DataType_OpMode()
113 The scaling factors C1 and C2 used in the equations are defined as fol‐
117 lows:
118 o For ScaleMode = 1, C1 = 1 and C2 = 2**order.
120 o For ScaleMode = 2, C1 = 2**order and C2 = 1.
122 o For ScaleMode = 3, C1 = C2 = 2**(order/2) when order is
124 even, or C1 = 2**((order+1)/2) and C2 = 2**((order-1)/2)
125 when order is odd.
126 o For ScaleMode = 4, C1 = 2**P and C2 = 2**Q, where P and Q
128 are adaptive scaling factors and are generated by the func‐
129 tions.
130 For functions with only real parts for the source signal, the imaginary
133 parts are assumed to be all zero. For functions with only real parts
134 for the destination signal, the imaginary parts are discarded. The
135 functions with only one data type in their names perform the operation
136 in place.
137
139 Each function takes some of the following arguments:
140 dstr Destination signal array that contains the real parts.
142 dsti Destination signal array that contains the imaginary parts.
145 srcr Source signal array that contains the real parts.
148 srci Source signal array that contains the imaginary parts.
151 dstc Complex destination signal array. dstc[2*i] contains the
154 real parts, and dstc[2*i+1] contains the imaginary parts.
155 srcc Complex source signal array. srcc[2*i] contains the real
158 parts, and srcc[2*i+1] contains the imaginary parts.
159 srcdstr Source and destination signal array that contains the real
162 parts.
163 srcdsti Source and destination signal array that contains the imagi‐
166 nary parts.
167 srcdstc Complex source and destination signal array. srcdstc[2*i]
170 contains the real parts, and srcdstc[2*i+1] contains the
171 imaginary parts.
172 order Order of the transformation. The base-2 logarithm of the
175 number of data samples.
176
179 The function returns MLIB_SUCCESS if successful. Otherwise it returns
180 MLIB_FAILURE.
181
183 See attributes(5) for descriptions of the following attributes:
184 ┌─────────────────────────────┬─────────────────────────────┐
189 │ ATTRIBUTE TYPE │ ATTRIBUTE VALUE │
190 ├─────────────────────────────┼─────────────────────────────┤
191 │Interface Stability │Committed │
192 ├─────────────────────────────┼─────────────────────────────┤
193 │MT-Level │MT-Safe │
194 └─────────────────────────────┴─────────────────────────────┘
195
197 mlib_SignalFFT_1(3MLIB), mlib_SignalFFT_3(3MLIB), mlib_Sig‐
198 nalFFT_4(3MLIB), mlib_SignalIFFT_1(3MLIB), mlib_SignalIFFT_2(3MLIB),
199 mlib_SignalIFFT_3(3MLIB), mlib_SignalIFFT_4(3MLIB), attributes(5)
200SunOS 5.11 2 Mar 2007 mlib_SignalFFT_2(3MLIB)