| /* | |
| * This file is part of FFmpeg. | |
| * | |
| * FFmpeg is free software; you can redistribute it and/or | |
| * modify it under the terms of the GNU Lesser General Public | |
| * License as published by the Free Software Foundation; either | |
| * version 2.1 of the License, or (at your option) any later version. | |
| * | |
| * FFmpeg is distributed in the hope that it will be useful, | |
| * but WITHOUT ANY WARRANTY; without even the implied warranty of | |
| * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU | |
| * Lesser General Public License for more details. | |
| * | |
| * You should have received a copy of the GNU Lesser General Public | |
| * License along with FFmpeg; if not, write to the Free Software | |
| * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA | |
| */ | |
| /** | |
| * @file | |
| * @ingroup lavc_fft | |
| * FFT functions | |
| */ | |
| /** | |
| * @defgroup lavc_fft FFT functions | |
| * @ingroup lavc_misc | |
| * | |
| * @{ | |
| */ | |
| typedef float FFTSample; | |
| typedef struct FFTComplex { | |
| FFTSample re, im; | |
| } FFTComplex; | |
| typedef struct FFTContext FFTContext; | |
| /** | |
| * Set up a complex FFT. | |
| * @param nbits log2 of the length of the input array | |
| * @param inverse if 0 perform the forward transform, if 1 perform the inverse | |
| * @deprecated use av_tx_init from libavutil/tx.h with a type of AV_TX_FLOAT_FFT | |
| */ | |
| attribute_deprecated | |
| FFTContext *av_fft_init(int nbits, int inverse); | |
| /** | |
| * Do the permutation needed BEFORE calling ff_fft_calc(). | |
| * @deprecated without replacement | |
| */ | |
| attribute_deprecated | |
| void av_fft_permute(FFTContext *s, FFTComplex *z); | |
| /** | |
| * Do a complex FFT with the parameters defined in av_fft_init(). The | |
| * input data must be permuted before. No 1.0/sqrt(n) normalization is done. | |
| * @deprecated use the av_tx_fn value returned by av_tx_init, which also does permutation | |
| */ | |
| attribute_deprecated | |
| void av_fft_calc(FFTContext *s, FFTComplex *z); | |
| attribute_deprecated | |
| void av_fft_end(FFTContext *s); | |
| /** | |
| * @deprecated use av_tx_init from libavutil/tx.h with a type of AV_TX_FLOAT_MDCT, | |
| * with a flag of AV_TX_FULL_IMDCT for a replacement to av_imdct_calc. | |
| */ | |
| attribute_deprecated | |
| FFTContext *av_mdct_init(int nbits, int inverse, double scale); | |
| attribute_deprecated | |
| void av_imdct_calc(FFTContext *s, FFTSample *output, const FFTSample *input); | |
| attribute_deprecated | |
| void av_imdct_half(FFTContext *s, FFTSample *output, const FFTSample *input); | |
| attribute_deprecated | |
| void av_mdct_calc(FFTContext *s, FFTSample *output, const FFTSample *input); | |
| attribute_deprecated | |
| void av_mdct_end(FFTContext *s); | |
| /* Real Discrete Fourier Transform */ | |
| enum RDFTransformType { | |
| DFT_R2C, | |
| IDFT_C2R, | |
| IDFT_R2C, | |
| DFT_C2R, | |
| }; | |
| typedef struct RDFTContext RDFTContext; | |
| /** | |
| * Set up a real FFT. | |
| * @param nbits log2 of the length of the input array | |
| * @param trans the type of transform | |
| * | |
| * @deprecated use av_tx_init from libavutil/tx.h with a type of AV_TX_FLOAT_RDFT | |
| */ | |
| attribute_deprecated | |
| RDFTContext *av_rdft_init(int nbits, enum RDFTransformType trans); | |
| attribute_deprecated | |
| void av_rdft_calc(RDFTContext *s, FFTSample *data); | |
| attribute_deprecated | |
| void av_rdft_end(RDFTContext *s); | |
| /* Discrete Cosine Transform */ | |
| typedef struct DCTContext DCTContext; | |
| enum DCTTransformType { | |
| DCT_II = 0, | |
| DCT_III, | |
| DCT_I, | |
| DST_I, | |
| }; | |
| /** | |
| * Set up DCT. | |
| * | |
| * @param nbits size of the input array: | |
| * (1 << nbits) for DCT-II, DCT-III and DST-I | |
| * (1 << nbits) + 1 for DCT-I | |
| * @param type the type of transform | |
| * | |
| * @note the first element of the input of DST-I is ignored | |
| * | |
| * @deprecated use av_tx_init from libavutil/tx.h with an appropriate type of AV_TX_FLOAT_DCT | |
| */ | |
| attribute_deprecated | |
| DCTContext *av_dct_init(int nbits, enum DCTTransformType type); | |
| attribute_deprecated | |
| void av_dct_calc(DCTContext *s, FFTSample *data); | |
| attribute_deprecated | |
| void av_dct_end (DCTContext *s); | |
| /** | |
| * @} | |
| */ | |