/* * 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 AVUTIL_TX_H #define AVUTIL_TX_H #include <stdint.h> #include <stddef.h> typedef struct AVTXContext AVTXContext; typedef struct AVComplexFloat { float re, im; } AVComplexFloat; enum AVTXType { /** * Standard complex to complex FFT with sample data type AVComplexFloat. * Scaling currently unsupported */ AV_TX_FLOAT_FFT = 0, /** * Standard MDCT with sample data type of float and a scale type of * float. Length is the frame size, not the window size (which is 2x frame) */ AV_TX_FLOAT_MDCT = 1, }; /** * Function pointer to a function to perform the transform. * * @note Using a different context than the one allocated during av_tx_init() * is not allowed. * * @param s the transform context * @param out the output array * @param in the input array * @param stride the input or output stride (depending on transform direction) * in bytes, currently implemented for all MDCT transforms */ typedef void (*av_tx_fn)(AVTXContext *s, void *out, void *in, ptrdiff_t stride); /** * Initialize a transform context with the given configuration * Currently power of two lengths from 4 to 131072 are supported, along with * any length decomposable to a power of two and either 3, 5 or 15. * * @param ctx the context to allocate, will be NULL on error * @param tx pointer to the transform function pointer to set * @param type type the type of transform * @param inv whether to do an inverse or a forward transform * @param len the size of the transform in samples * @param scale pointer to the value to scale the output if supported by type * @param flags currently unused * * @return 0 on success, negative error code on failure */ int av_tx_init(AVTXContext **ctx, av_tx_fn *tx, enum AVTXType type, int inv, int len, const void *scale, uint64_t flags); /** * Frees a context and sets ctx to NULL, does nothing when ctx == NULL */ void av_tx_uninit(AVTXContext **ctx); #endif /* AVUTIL_TX_H */