xref: /aosp_15_r20/external/libxaac/encoder/iusace_fft.h (revision 15dc779a375ca8b5125643b829a8aa4b70d7f451)
1 /******************************************************************************
2  *                                                                            *
3  * Copyright (C) 2023 The Android Open Source Project
4  *
5  * Licensed under the Apache License, Version 2.0 (the "License");
6  * you may not use this file except in compliance with the License.
7  * You may obtain a copy of the License at:
8  *
9  * http://www.apache.org/licenses/LICENSE-2.0
10  *
11  * Unless required by applicable law or agreed to in writing, software
12  * distributed under the License is distributed on an "AS IS" BASIS,
13  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
14  * See the License for the specific language governing permissions and
15  * limitations under the License.
16  *
17  *****************************************************************************
18  * Originally developed and contributed by Ittiam Systems Pvt. Ltd, Bangalore
19  */
20 
21 #pragma once
22 
23 #define C70 (-0.1666667014f)  //(cos(u) + cos(2 * u) + cos(3 * u)) / 3;
24 #define C71 (0.7901564837f)   //(2 * cos(u) - cos(2 * u) - cos(3 * u)) / 3;
25 #define C72 (0.0558542535f)   //(cos(u) - 2 * cos(2 * u) + cos(3 * u)) / 3;
26 #define C73 (0.7343022227f)   //(cos(u) + cos(2 * u) - 2 * cos(3 * u)) / 3;
27 #define C74 (-0.4409585893f)  //(sin(u) + sin(2 * u) - sin(3 * u)) / 3;
28 #define C75 (-0.3408728838f)  //(2 * sin(u) - sin(2 * u) + sin(3 * u)) / 3;
29 #define C76 (0.5339693427f)   //(sin(u) - 2 * sin(2 * u) - sin(3 * u)) / 3;
30 #define C77 (-0.8748422265f)  //(sin(u) + sin(2 * u) + 2 * sin(3 * u)) / 3;
31 
32 #define CPLX_MPY_FFT(re, im, a, b, c, d) \
33   {                                      \
34     re = ((a * c) - (b * d));            \
35     im = ((a * d) + (b * c));            \
36   }
37 
38 IA_ERRORCODE iusace_fft_based_mdct(FLOAT64 *ptr_in, FLOAT64 *ptr_out, WORD32 npoints,
39                                    const WORD32 tx_flag, iusace_scratch_mem *pstr_scratch);
40 
41 VOID iusace_complex_fft(FLOAT32 *data, WORD32 nlength, iusace_scratch_mem *pstr_scratch);
42