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diff --git a/dependencies/include/libavutil/tx.h b/dependencies/include/libavutil/tx.h
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+/*
+ * 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;
+
+typedef struct AVComplexDouble {
+    double re, im;
+} AVComplexDouble;
+
+typedef struct AVComplexInt32 {
+    int32_t re, im;
+} AVComplexInt32;
+
+enum AVTXType {
+    /**
+     * Standard complex to complex FFT with sample data type of AVComplexFloat,
+     * AVComplexDouble or AVComplexInt32, for each respective variant.
+     *
+     * Output is not 1/len normalized. Scaling currently unsupported.
+     * The stride parameter must be set to the size of a single sample in bytes.
+     */
+    AV_TX_FLOAT_FFT  = 0,
+    AV_TX_DOUBLE_FFT = 2,
+    AV_TX_INT32_FFT  = 4,
+
+    /**
+     * Standard MDCT with a sample data type of float, double or int32_t,
+     * respecively. For the float and int32 variants, the scale type is
+     * 'float', while for the double variant, it's 'double'.
+     * If scale is NULL, 1.0 will be used as a default.
+     *
+     * Length is the frame size, not the window size (which is 2x frame).
+     * For forward transforms, the stride specifies the spacing between each
+     * sample in the output array in bytes. The input must be a flat array.
+     *
+     * For inverse transforms, the stride specifies the spacing between each
+     * sample in the input array in bytes. The output must be a flat array.
+     *
+     * NOTE: the inverse transform is half-length, meaning the output will not
+     * contain redundant data. This is what most codecs work with. To do a full
+     * inverse transform, set the AV_TX_FULL_IMDCT flag on init.
+     */
+    AV_TX_FLOAT_MDCT  = 1,
+    AV_TX_DOUBLE_MDCT = 3,
+    AV_TX_INT32_MDCT  = 5,
+
+    /**
+     * Real to complex and complex to real DFTs.
+     * For the float and int32 variants, the scale type is 'float', while for
+     * the double variant, it's a 'double'. If scale is NULL, 1.0 will be used
+     * as a default.
+     *
+     * For forward transforms (R2C), stride must be the spacing between two
+     * samples in bytes. For inverse transforms, the stride must be set
+     * to the spacing between two complex values in bytes.
+     *
+     * The forward transform performs a real-to-complex DFT of N samples to
+     * N/2+1 complex values.
+     *
+     * The inverse transform performs a complex-to-real DFT of N/2+1 complex
+     * values to N real samples. The output is not normalized, but can be
+     * made so by setting the scale value to 1.0/len.
+     * NOTE: the inverse transform always overwrites the input.
+     */
+    AV_TX_FLOAT_RDFT  = 6,
+    AV_TX_DOUBLE_RDFT = 7,
+    AV_TX_INT32_RDFT  = 8,
+
+    /**
+     * Real to real (DCT) transforms.
+     *
+     * The forward transform is a DCT-II.
+     * The inverse transform is a DCT-III.
+     *
+     * The input array is always overwritten. DCT-III requires that the
+     * input be padded with 2 extra samples. Stride must be set to the
+     * spacing between two samples in bytes.
+     */
+    AV_TX_FLOAT_DCT  = 9,
+    AV_TX_DOUBLE_DCT = 10,
+    AV_TX_INT32_DCT  = 11,
+
+    /* Not part of the API, do not use */
+    AV_TX_NB,
+};
+
+/**
+ * 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 in bytes
+ *
+ * The out and in arrays must be aligned to the maximum required by the CPU
+ * architecture unless the AV_TX_UNALIGNED flag was set in av_tx_init().
+ * The stride must follow the constraints the transform type has specified.
+ */
+typedef void (*av_tx_fn)(AVTXContext *s, void *out, void *in, ptrdiff_t stride);
+
+/**
+ * Flags for av_tx_init()
+ */
+enum AVTXFlags {
+    /**
+     * Allows for in-place transformations, where input == output.
+     * May be unsupported or slower for some transform types.
+     */
+    AV_TX_INPLACE = 1ULL << 0,
+
+    /**
+     * Relaxes alignment requirement for the in and out arrays of av_tx_fn().
+     * May be slower with certain transform types.
+     */
+    AV_TX_UNALIGNED = 1ULL << 1,
+
+    /**
+     * Performs a full inverse MDCT rather than leaving out samples that can be
+     * derived through symmetry. Requires an output array of 'len' floats,
+     * rather than the usual 'len/2' floats.
+     * Ignored for all transforms but inverse MDCTs.
+     */
+    AV_TX_FULL_IMDCT = 1ULL << 2,
+};
+
+/**
+ * Initialize a transform context with the given configuration
+ * (i)MDCTs with an odd length are currently not supported.
+ *
+ * @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 a bitmask of AVTXFlags or 0
+ *
+ * @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 */