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fft-internal.h
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1 /*
2  * This file is part of FFmpeg.
3  *
4  * FFmpeg is free software; you can redistribute it and/or
5  * modify it under the terms of the GNU Lesser General Public
6  * License as published by the Free Software Foundation; either
7  * version 2.1 of the License, or (at your option) any later version.
8  *
9  * FFmpeg is distributed in the hope that it will be useful,
10  * but WITHOUT ANY WARRANTY; without even the implied warranty of
11  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
12  * Lesser General Public License for more details.
13  *
14  * You should have received a copy of the GNU Lesser General Public
15  * License along with FFmpeg; if not, write to the Free Software
16  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
17  */
18 
19 #ifndef AVCODEC_FFT_INTERNAL_H
20 #define AVCODEC_FFT_INTERNAL_H
21 
22 #if CONFIG_FFT_FLOAT
23 
24 #define FIX15(v) (v)
25 #define sqrthalf (float)M_SQRT1_2
26 
27 #define BF(x, y, a, b) do { \
28  x = a - b; \
29  y = a + b; \
30  } while (0)
31 
32 #define CMUL(dre, dim, are, aim, bre, bim) do { \
33  (dre) = (are) * (bre) - (aim) * (bim); \
34  (dim) = (are) * (bim) + (aim) * (bre); \
35  } while (0)
36 
37 #else
38 
39 #include "libavutil/intmath.h"
40 #include "mathops.h"
41 
42 void ff_mdct_calcw_c(FFTContext *s, FFTDouble *output, const FFTSample *input);
43 
44 #define SCALE_FLOAT(a, bits) lrint((a) * (double)(1 << (bits)))
45 #define FIX15(a) av_clip(SCALE_FLOAT(a, 15), -32767, 32767)
46 
47 #define sqrthalf ((int16_t)((1<<15)*M_SQRT1_2))
48 
49 #define BF(x, y, a, b) do { \
50  x = (a - b) >> 1; \
51  y = (a + b) >> 1; \
52  } while (0)
53 
54 #define CMULS(dre, dim, are, aim, bre, bim, sh) do { \
55  (dre) = (MUL16(are, bre) - MUL16(aim, bim)) >> sh; \
56  (dim) = (MUL16(are, bim) + MUL16(aim, bre)) >> sh; \
57  } while (0)
58 
59 #define CMUL(dre, dim, are, aim, bre, bim) \
60  CMULS(dre, dim, are, aim, bre, bim, 15)
61 
62 #define CMULL(dre, dim, are, aim, bre, bim) \
63  CMULS(dre, dim, are, aim, bre, bim, 0)
64 
65 #endif /* CONFIG_FFT_FLOAT */
66 
67 #define ff_imdct_calc_c FFT_NAME(ff_imdct_calc_c)
68 #define ff_imdct_half_c FFT_NAME(ff_imdct_half_c)
69 #define ff_mdct_calc_c FFT_NAME(ff_mdct_calc_c)
70 
71 void ff_imdct_calc_c(FFTContext *s, FFTSample *output, const FFTSample *input);
72 void ff_imdct_half_c(FFTContext *s, FFTSample *output, const FFTSample *input);
73 void ff_mdct_calc_c(FFTContext *s, FFTSample *output, const FFTSample *input);
74 
75 #endif /* AVCODEC_FFT_INTERNAL_H */