/*
  * 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 */