/* Copyright (c) 2007-2008 CSIRO | |

Copyright (c) 2007-2008 Xiph.Org Foundation | |

Written by Jean-Marc Valin */ | |

/* | |

Redistribution and use in source and binary forms, with or without | |

modification, are permitted provided that the following conditions | |

are met: | |

- Redistributions of source code must retain the above copyright | |

notice, this list of conditions and the following disclaimer. | |

- Redistributions in binary form must reproduce the above copyright | |

notice, this list of conditions and the following disclaimer in the | |

documentation and/or other materials provided with the distribution. | |

THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS | |

``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT | |

LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR | |

A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER | |

OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, | |

EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, | |

PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR | |

PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF | |

LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING | |

NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS | |

SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. | |

*/ | |

/* This is a simple MDCT implementation that uses a N/4 complex FFT | |

to do most of the work. It should be relatively straightforward to | |

plug in pretty much and FFT here. | |

This replaces the Vorbis FFT (and uses the exact same API), which | |

was a bit too messy and that was ending up duplicating code | |

(might as well use the same FFT everywhere). | |

The algorithm is similar to (and inspired from) Fabrice Bellard's | |

MDCT implementation in FFMPEG, but has differences in signs, ordering | |

and scaling in many places. | |

*/ | |

#ifndef MDCT_H | |

#define MDCT_H | |

#include "opus_defines.h" | |

#include "kiss_fft.h" | |

#include "arch.h" | |

typedef struct { | |

int n; | |

int maxshift; | |

const kiss_fft_state *kfft[4]; | |

const kiss_twiddle_scalar * OPUS_RESTRICT trig; | |

} mdct_lookup; | |

#if defined(HAVE_ARM_NE10) | |

#include "arm/mdct_arm.h" | |

#endif | |

int clt_mdct_init(mdct_lookup *l,int N, int maxshift, int arch); | |

void clt_mdct_clear(mdct_lookup *l, int arch); | |

/** Compute a forward MDCT and scale by 4/N, trashes the input array */ | |

void clt_mdct_forward_c(const mdct_lookup *l, kiss_fft_scalar *in, | |

kiss_fft_scalar * OPUS_RESTRICT out, | |

const opus_val16 *window, int overlap, | |

int shift, int stride, int arch); | |

/** Compute a backward MDCT (no scaling) and performs weighted overlap-add | |

(scales implicitly by 1/2) */ | |

void clt_mdct_backward_c(const mdct_lookup *l, kiss_fft_scalar *in, | |

kiss_fft_scalar * OPUS_RESTRICT out, | |

const opus_val16 * OPUS_RESTRICT window, | |

int overlap, int shift, int stride, int arch); | |

#if !defined(OVERRIDE_OPUS_MDCT) | |

/* Is run-time CPU detection enabled on this platform? */ | |

#if defined(OPUS_HAVE_RTCD) && defined(HAVE_ARM_NE10) | |

extern void (*const CLT_MDCT_FORWARD_IMPL[OPUS_ARCHMASK+1])( | |

const mdct_lookup *l, kiss_fft_scalar *in, | |

kiss_fft_scalar * OPUS_RESTRICT out, const opus_val16 *window, | |

int overlap, int shift, int stride, int arch); | |

#define clt_mdct_forward(_l, _in, _out, _window, _overlap, _shift, _stride, _arch) \ | |

((*CLT_MDCT_FORWARD_IMPL[(arch)&OPUS_ARCHMASK])(_l, _in, _out, \ | |

_window, _overlap, _shift, \ | |

_stride, _arch)) | |

extern void (*const CLT_MDCT_BACKWARD_IMPL[OPUS_ARCHMASK+1])( | |

const mdct_lookup *l, kiss_fft_scalar *in, | |

kiss_fft_scalar * OPUS_RESTRICT out, const opus_val16 *window, | |

int overlap, int shift, int stride, int arch); | |

#define clt_mdct_backward(_l, _in, _out, _window, _overlap, _shift, _stride, _arch) \ | |

(*CLT_MDCT_BACKWARD_IMPL[(arch)&OPUS_ARCHMASK])(_l, _in, _out, \ | |

_window, _overlap, _shift, \ | |

_stride, _arch) | |

#else /* if defined(OPUS_HAVE_RTCD) && defined(HAVE_ARM_NE10) */ | |

#define clt_mdct_forward(_l, _in, _out, _window, _overlap, _shift, _stride, _arch) \ | |

clt_mdct_forward_c(_l, _in, _out, _window, _overlap, _shift, _stride, _arch) | |

#define clt_mdct_backward(_l, _in, _out, _window, _overlap, _shift, _stride, _arch) \ | |

clt_mdct_backward_c(_l, _in, _out, _window, _overlap, _shift, _stride, _arch) | |

#endif /* end if defined(OPUS_HAVE_RTCD) && defined(HAVE_ARM_NE10) && !defined(FIXED_POINT) */ | |

#endif /* end if !defined(OVERRIDE_OPUS_MDCT) */ | |

#endif |