avfft.h (4081B)
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_AVFFT_H 20 #define AVCODEC_AVFFT_H 21 22 #include "libavutil/attributes.h" 23 #include "version_major.h" 24 #if FF_API_AVFFT 25 26 /** 27 * @file 28 * @ingroup lavc_fft 29 * FFT functions 30 */ 31 32 /** 33 * @defgroup lavc_fft FFT functions 34 * @ingroup lavc_misc 35 * 36 * @{ 37 */ 38 39 typedef float FFTSample; 40 41 typedef struct FFTComplex { 42 FFTSample re, im; 43 } FFTComplex; 44 45 typedef struct FFTContext FFTContext; 46 47 /** 48 * Set up a complex FFT. 49 * @param nbits log2 of the length of the input array 50 * @param inverse if 0 perform the forward transform, if 1 perform the inverse 51 * @deprecated use av_tx_init from libavutil/tx.h with a type of AV_TX_FLOAT_FFT 52 */ 53 attribute_deprecated 54 FFTContext *av_fft_init(int nbits, int inverse); 55 56 /** 57 * Do the permutation needed BEFORE calling ff_fft_calc(). 58 * @deprecated without replacement 59 */ 60 attribute_deprecated 61 void av_fft_permute(FFTContext *s, FFTComplex *z); 62 63 /** 64 * Do a complex FFT with the parameters defined in av_fft_init(). The 65 * input data must be permuted before. No 1.0/sqrt(n) normalization is done. 66 * @deprecated use the av_tx_fn value returned by av_tx_init, which also does permutation 67 */ 68 attribute_deprecated 69 void av_fft_calc(FFTContext *s, FFTComplex *z); 70 71 attribute_deprecated 72 void av_fft_end(FFTContext *s); 73 74 /** 75 * @deprecated use av_tx_init from libavutil/tx.h with a type of AV_TX_FLOAT_MDCT, 76 * with a flag of AV_TX_FULL_IMDCT for a replacement to av_imdct_calc. 77 */ 78 attribute_deprecated 79 FFTContext *av_mdct_init(int nbits, int inverse, double scale); 80 attribute_deprecated 81 void av_imdct_calc(FFTContext *s, FFTSample *output, const FFTSample *input); 82 attribute_deprecated 83 void av_imdct_half(FFTContext *s, FFTSample *output, const FFTSample *input); 84 attribute_deprecated 85 void av_mdct_calc(FFTContext *s, FFTSample *output, const FFTSample *input); 86 attribute_deprecated 87 void av_mdct_end(FFTContext *s); 88 89 /* Real Discrete Fourier Transform */ 90 91 enum RDFTransformType { 92 DFT_R2C, 93 IDFT_C2R, 94 IDFT_R2C, 95 DFT_C2R, 96 }; 97 98 typedef struct RDFTContext RDFTContext; 99 100 /** 101 * Set up a real FFT. 102 * @param nbits log2 of the length of the input array 103 * @param trans the type of transform 104 * 105 * @deprecated use av_tx_init from libavutil/tx.h with a type of AV_TX_FLOAT_RDFT 106 */ 107 attribute_deprecated 108 RDFTContext *av_rdft_init(int nbits, enum RDFTransformType trans); 109 attribute_deprecated 110 void av_rdft_calc(RDFTContext *s, FFTSample *data); 111 attribute_deprecated 112 void av_rdft_end(RDFTContext *s); 113 114 /* Discrete Cosine Transform */ 115 116 typedef struct DCTContext DCTContext; 117 118 enum DCTTransformType { 119 DCT_II = 0, 120 DCT_III, 121 DCT_I, 122 DST_I, 123 }; 124 125 /** 126 * Set up DCT. 127 * 128 * @param nbits size of the input array: 129 * (1 << nbits) for DCT-II, DCT-III and DST-I 130 * (1 << nbits) + 1 for DCT-I 131 * @param type the type of transform 132 * 133 * @note the first element of the input of DST-I is ignored 134 * 135 * @deprecated use av_tx_init from libavutil/tx.h with an appropriate type of AV_TX_FLOAT_DCT 136 */ 137 attribute_deprecated 138 DCTContext *av_dct_init(int nbits, enum DCTTransformType type); 139 attribute_deprecated 140 void av_dct_calc(DCTContext *s, FFTSample *data); 141 attribute_deprecated 142 void av_dct_end (DCTContext *s); 143 144 /** 145 * @} 146 */ 147 148 #endif /* FF_API_AVFFT */ 149 #endif /* AVCODEC_AVFFT_H */