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Diffstat (limited to 'dom/media/platforms/ffmpeg/ffmpeg58/include/libavcodec/avfft.h')
-rw-r--r-- | dom/media/platforms/ffmpeg/ffmpeg58/include/libavcodec/avfft.h | 118 |
1 files changed, 118 insertions, 0 deletions
diff --git a/dom/media/platforms/ffmpeg/ffmpeg58/include/libavcodec/avfft.h b/dom/media/platforms/ffmpeg/ffmpeg58/include/libavcodec/avfft.h new file mode 100644 index 000000000..0c0f9b8d8 --- /dev/null +++ b/dom/media/platforms/ffmpeg/ffmpeg58/include/libavcodec/avfft.h @@ -0,0 +1,118 @@ +/* + * 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 + */ + +#ifndef AVCODEC_AVFFT_H +#define AVCODEC_AVFFT_H + +/** + * @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 + */ +FFTContext *av_fft_init(int nbits, int inverse); + +/** + * Do the permutation needed BEFORE calling ff_fft_calc(). + */ +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. + */ +void av_fft_calc(FFTContext *s, FFTComplex *z); + +void av_fft_end(FFTContext *s); + +FFTContext *av_mdct_init(int nbits, int inverse, double scale); +void av_imdct_calc(FFTContext *s, FFTSample *output, const FFTSample *input); +void av_imdct_half(FFTContext *s, FFTSample *output, const FFTSample *input); +void av_mdct_calc(FFTContext *s, FFTSample *output, const FFTSample *input); +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 + */ +RDFTContext *av_rdft_init(int nbits, enum RDFTransformType trans); +void av_rdft_calc(RDFTContext *s, FFTSample *data); +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 + */ +DCTContext *av_dct_init(int nbits, enum DCTTransformType type); +void av_dct_calc(DCTContext *s, FFTSample *data); +void av_dct_end (DCTContext *s); + +/** + * @} + */ + +#endif /* AVCODEC_AVFFT_H */ |