Chris@69: /* Copyright (c) 2007-2008 CSIRO
Chris@69:    Copyright (c) 2007-2008 Xiph.Org Foundation
Chris@69:    Written by Jean-Marc Valin */
Chris@69: /*
Chris@69:    Redistribution and use in source and binary forms, with or without
Chris@69:    modification, are permitted provided that the following conditions
Chris@69:    are met:
Chris@69: 
Chris@69:    - Redistributions of source code must retain the above copyright
Chris@69:    notice, this list of conditions and the following disclaimer.
Chris@69: 
Chris@69:    - Redistributions in binary form must reproduce the above copyright
Chris@69:    notice, this list of conditions and the following disclaimer in the
Chris@69:    documentation and/or other materials provided with the distribution.
Chris@69: 
Chris@69:    THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
Chris@69:    ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
Chris@69:    LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
Chris@69:    A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER
Chris@69:    OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
Chris@69:    EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
Chris@69:    PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
Chris@69:    PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
Chris@69:    LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
Chris@69:    NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
Chris@69:    SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
Chris@69: */
Chris@69: 
Chris@69: /* This is a simple MDCT implementation that uses a N/4 complex FFT
Chris@69:    to do most of the work. It should be relatively straightforward to
Chris@69:    plug in pretty much and FFT here.
Chris@69: 
Chris@69:    This replaces the Vorbis FFT (and uses the exact same API), which
Chris@69:    was a bit too messy and that was ending up duplicating code
Chris@69:    (might as well use the same FFT everywhere).
Chris@69: 
Chris@69:    The algorithm is similar to (and inspired from) Fabrice Bellard's
Chris@69:    MDCT implementation in FFMPEG, but has differences in signs, ordering
Chris@69:    and scaling in many places.
Chris@69: */
Chris@69: 
Chris@69: #ifndef MDCT_H
Chris@69: #define MDCT_H
Chris@69: 
Chris@69: #include "opus_defines.h"
Chris@69: #include "kiss_fft.h"
Chris@69: #include "arch.h"
Chris@69: 
Chris@69: typedef struct {
Chris@69:    int n;
Chris@69:    int maxshift;
Chris@69:    const kiss_fft_state *kfft[4];
Chris@69:    const kiss_twiddle_scalar * OPUS_RESTRICT trig;
Chris@69: } mdct_lookup;
Chris@69: 
Chris@69: #if defined(HAVE_ARM_NE10)
Chris@69: #include "arm/mdct_arm.h"
Chris@69: #endif
Chris@69: 
Chris@69: 
Chris@69: int clt_mdct_init(mdct_lookup *l,int N, int maxshift, int arch);
Chris@69: void clt_mdct_clear(mdct_lookup *l, int arch);
Chris@69: 
Chris@69: /** Compute a forward MDCT and scale by 4/N, trashes the input array */
Chris@69: void clt_mdct_forward_c(const mdct_lookup *l, kiss_fft_scalar *in,
Chris@69:                         kiss_fft_scalar * OPUS_RESTRICT out,
Chris@69:                         const opus_val16 *window, int overlap,
Chris@69:                         int shift, int stride, int arch);
Chris@69: 
Chris@69: /** Compute a backward MDCT (no scaling) and performs weighted overlap-add
Chris@69:     (scales implicitly by 1/2) */
Chris@69: void clt_mdct_backward_c(const mdct_lookup *l, kiss_fft_scalar *in,
Chris@69:       kiss_fft_scalar * OPUS_RESTRICT out,
Chris@69:       const opus_val16 * OPUS_RESTRICT window,
Chris@69:       int overlap, int shift, int stride, int arch);
Chris@69: 
Chris@69: #if !defined(OVERRIDE_OPUS_MDCT)
Chris@69: /* Is run-time CPU detection enabled on this platform? */
Chris@69: #if defined(OPUS_HAVE_RTCD) && defined(HAVE_ARM_NE10)
Chris@69: 
Chris@69: extern void (*const CLT_MDCT_FORWARD_IMPL[OPUS_ARCHMASK+1])(
Chris@69:       const mdct_lookup *l, kiss_fft_scalar *in,
Chris@69:       kiss_fft_scalar * OPUS_RESTRICT out, const opus_val16 *window,
Chris@69:       int overlap, int shift, int stride, int arch);
Chris@69: 
Chris@69: #define clt_mdct_forward(_l, _in, _out, _window, _overlap, _shift, _stride, _arch) \
Chris@69:    ((*CLT_MDCT_FORWARD_IMPL[(arch)&OPUS_ARCHMASK])(_l, _in, _out, \
Chris@69:                                                    _window, _overlap, _shift, \
Chris@69:                                                    _stride, _arch))
Chris@69: 
Chris@69: extern void (*const CLT_MDCT_BACKWARD_IMPL[OPUS_ARCHMASK+1])(
Chris@69:       const mdct_lookup *l, kiss_fft_scalar *in,
Chris@69:       kiss_fft_scalar * OPUS_RESTRICT out, const opus_val16 *window,
Chris@69:       int overlap, int shift, int stride, int arch);
Chris@69: 
Chris@69: #define clt_mdct_backward(_l, _in, _out, _window, _overlap, _shift, _stride, _arch) \
Chris@69:    (*CLT_MDCT_BACKWARD_IMPL[(arch)&OPUS_ARCHMASK])(_l, _in, _out, \
Chris@69:                                                    _window, _overlap, _shift, \
Chris@69:                                                    _stride, _arch)
Chris@69: 
Chris@69: #else /* if defined(OPUS_HAVE_RTCD) && defined(HAVE_ARM_NE10) */
Chris@69: 
Chris@69: #define clt_mdct_forward(_l, _in, _out, _window, _overlap, _shift, _stride, _arch) \
Chris@69:    clt_mdct_forward_c(_l, _in, _out, _window, _overlap, _shift, _stride, _arch)
Chris@69: 
Chris@69: #define clt_mdct_backward(_l, _in, _out, _window, _overlap, _shift, _stride, _arch) \
Chris@69:    clt_mdct_backward_c(_l, _in, _out, _window, _overlap, _shift, _stride, _arch)
Chris@69: 
Chris@69: #endif /* end if defined(OPUS_HAVE_RTCD) && defined(HAVE_ARM_NE10) && !defined(FIXED_POINT) */
Chris@69: #endif /* end if !defined(OVERRIDE_OPUS_MDCT) */
Chris@69: 
Chris@69: #endif