Move FFT parts from dsputil.h to fft.h

Originally committed as revision 22235 to svn://svn.ffmpeg.org/ffmpeg/trunk

1 files changed, 244 insertions, 0 deletions

diff --git a/libavcodec/fft.h b/libavcodec/fft.h
new file mode 100644
index 0000000000..f3e7d7aa4e
--- /dev/null
+++ b/libavcodec/fft.h
@@ -0,0 +1,244 @@
+/*
+ * Copyright (c) 2000, 2001, 2002 Fabrice Bellard
+ * Copyright (c) 2002-2004 Michael Niedermayer <michaelni@gmx.at>
+ *
+ * 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_FFT_H
+#define AVCODEC_FFT_H
+
+#include <stdint.h>
+#include "config.h"
+#include "libavutil/mem.h"
+
+/* FFT computation */
+
+/* NOTE: soon integer code will be added, so you must use the
+   FFTSample type */
+typedef float FFTSample;
+
+typedef struct FFTComplex {
+    FFTSample re, im;
+} FFTComplex;
+
+typedef struct FFTContext {
+    int nbits;
+    int inverse;
+    uint16_t *revtab;
+    FFTComplex *exptab;
+    FFTComplex *exptab1; /* only used by SSE code */
+    FFTComplex *tmp_buf;
+    int mdct_size; /* size of MDCT (i.e. number of input data * 2) */
+    int mdct_bits; /* n = 2^nbits */
+    /* pre/post rotation tables */
+    FFTSample *tcos;
+    FFTSample *tsin;
+    void (*fft_permute)(struct FFTContext *s, FFTComplex *z);
+    void (*fft_calc)(struct FFTContext *s, FFTComplex *z);
+    void (*imdct_calc)(struct FFTContext *s, FFTSample *output, const FFTSample *input);
+    void (*imdct_half)(struct FFTContext *s, FFTSample *output, const FFTSample *input);
+    void (*mdct_calc)(struct FFTContext *s, FFTSample *output, const FFTSample *input);
+    int split_radix;
+    int permutation;
+#define FF_MDCT_PERM_NONE       0
+#define FF_MDCT_PERM_INTERLEAVE 1
+} FFTContext;
+
+#if CONFIG_HARDCODED_TABLES
+#define COSTABLE_CONST const
+#define SINTABLE_CONST const
+#define SINETABLE_CONST const
+#else
+#define COSTABLE_CONST
+#define SINTABLE_CONST
+#define SINETABLE_CONST
+#endif
+
+#define COSTABLE(size) \
+    COSTABLE_CONST DECLARE_ALIGNED(16, FFTSample, ff_cos_##size)[size/2]
+#define SINTABLE(size) \
+    SINTABLE_CONST DECLARE_ALIGNED(16, FFTSample, ff_sin_##size)[size/2]
+#define SINETABLE(size) \
+    SINETABLE_CONST DECLARE_ALIGNED(16, float, ff_sine_##size)[size]
+extern COSTABLE(16);
+extern COSTABLE(32);
+extern COSTABLE(64);
+extern COSTABLE(128);
+extern COSTABLE(256);
+extern COSTABLE(512);
+extern COSTABLE(1024);
+extern COSTABLE(2048);
+extern COSTABLE(4096);
+extern COSTABLE(8192);
+extern COSTABLE(16384);
+extern COSTABLE(32768);
+extern COSTABLE(65536);
+extern COSTABLE_CONST FFTSample* const ff_cos_tabs[17];
+
+/**
+ * Initializes the cosine table in ff_cos_tabs[index]
+ * \param index index in ff_cos_tabs array of the table to initialize
+ */
+void ff_init_ff_cos_tabs(int index);
+
+extern SINTABLE(16);
+extern SINTABLE(32);
+extern SINTABLE(64);
+extern SINTABLE(128);
+extern SINTABLE(256);
+extern SINTABLE(512);
+extern SINTABLE(1024);
+extern SINTABLE(2048);
+extern SINTABLE(4096);
+extern SINTABLE(8192);
+extern SINTABLE(16384);
+extern SINTABLE(32768);
+extern SINTABLE(65536);
+
+/**
+ * Sets 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
+ */
+int ff_fft_init(FFTContext *s, int nbits, int inverse);
+void ff_fft_permute_c(FFTContext *s, FFTComplex *z);
+void ff_fft_calc_c(FFTContext *s, FFTComplex *z);
+
+void ff_fft_init_altivec(FFTContext *s);
+void ff_fft_init_mmx(FFTContext *s);
+void ff_fft_init_arm(FFTContext *s);
+
+/**
+ * Do the permutation needed BEFORE calling ff_fft_calc().
+ */
+static inline void ff_fft_permute(FFTContext *s, FFTComplex *z)
+{
+    s->fft_permute(s, z);
+}
+/**
+ * Do a complex FFT with the parameters defined in ff_fft_init(). The
+ * input data must be permuted before. No 1.0/sqrt(n) normalization is done.
+ */
+static inline void ff_fft_calc(FFTContext *s, FFTComplex *z)
+{
+    s->fft_calc(s, z);
+}
+void ff_fft_end(FFTContext *s);
+
+/* MDCT computation */
+
+static inline void ff_imdct_calc(FFTContext *s, FFTSample *output, const FFTSample *input)
+{
+    s->imdct_calc(s, output, input);
+}
+static inline void ff_imdct_half(FFTContext *s, FFTSample *output, const FFTSample *input)
+{
+    s->imdct_half(s, output, input);
+}
+
+static inline void ff_mdct_calc(FFTContext *s, FFTSample *output,
+                                const FFTSample *input)
+{
+    s->mdct_calc(s, output, input);
+}
+
+/**
+ * Generate a Kaiser-Bessel Derived Window.
+ * @param   window  pointer to half window
+ * @param   alpha   determines window shape
+ * @param   n       size of half window
+ */
+void ff_kbd_window_init(float *window, float alpha, int n);
+
+/**
+ * Generate a sine window.
+ * @param   window  pointer to half window
+ * @param   n       size of half window
+ */
+void ff_sine_window_init(float *window, int n);
+
+/**
+ * initialize the specified entry of ff_sine_windows
+ */
+void ff_init_ff_sine_windows(int index);
+extern SINETABLE(  32);
+extern SINETABLE(  64);
+extern SINETABLE( 128);
+extern SINETABLE( 256);
+extern SINETABLE( 512);
+extern SINETABLE(1024);
+extern SINETABLE(2048);
+extern SINETABLE(4096);
+extern SINETABLE_CONST float * const ff_sine_windows[13];
+
+int ff_mdct_init(FFTContext *s, int nbits, int inverse, double scale);
+void ff_imdct_calc_c(FFTContext *s, FFTSample *output, const FFTSample *input);
+void ff_imdct_half_c(FFTContext *s, FFTSample *output, const FFTSample *input);
+void ff_mdct_calc_c(FFTContext *s, FFTSample *output, const FFTSample *input);
+void ff_mdct_end(FFTContext *s);
+
+/* Real Discrete Fourier Transform */
+
+enum RDFTransformType {
+    RDFT,
+    IRDFT,
+    RIDFT,
+    IRIDFT,
+};
+
+typedef struct {
+    int nbits;
+    int inverse;
+    int sign_convention;
+
+    /* pre/post rotation tables */
+    const FFTSample *tcos;
+    SINTABLE_CONST FFTSample *tsin;
+    FFTContext fft;
+} RDFTContext;
+
+/**
+ * Sets up a real FFT.
+ * @param nbits           log2 of the length of the input array
+ * @param trans           the type of transform
+ */
+int ff_rdft_init(RDFTContext *s, int nbits, enum RDFTransformType trans);
+void ff_rdft_calc(RDFTContext *s, FFTSample *data);
+void ff_rdft_end(RDFTContext *s);
+
+/* Discrete Cosine Transform */
+
+typedef struct {
+    int nbits;
+    int inverse;
+    FFTSample *data;
+    RDFTContext rdft;
+    const float *costab;
+    FFTSample *csc2;
+} DCTContext;
+
+/**
+ * Sets up (Inverse)DCT.
+ * @param nbits           log2 of the length of the input array
+ * @param inverse         >0 forward transform, <0 inverse transform
+ */
+int  ff_dct_init(DCTContext *s, int nbits, int inverse);
+void ff_dct_calc(DCTContext *s, FFTSample *data);
+void ff_dct_end (DCTContext *s);
+
+#endif /* AVCODEC_FFT_H */