Rename ffmpeg-4.2-fit to ffmpeg-4-fit

trunk/3rdparty/ffmpeg-4-fit/libavutil/tx.h

@@ -0,0 +1,81 @@
+/*
+ * 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 */