chromium/third_party/opus/src/celt/bands.c

/* Copyright (c) 2007-2008 CSIRO
   Copyright (c) 2007-2009 Xiph.Org Foundation
   Copyright (c) 2008-2009 Gregory Maxwell
   Written by Jean-Marc Valin and Gregory Maxwell */
/*
   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.
*/

#ifdef HAVE_CONFIG_H
#include "config.h"
#endif

#include <math.h>
#include "bands.h"
#include "modes.h"
#include "vq.h"
#include "cwrs.h"
#include "stack_alloc.h"
#include "os_support.h"
#include "mathops.h"
#include "rate.h"
#include "quant_bands.h"
#include "pitch.h"

int hysteresis_decision(opus_val16 val, const opus_val16 *thresholds, const opus_val16 *hysteresis, int N, int prev)
{ … }

opus_uint32 celt_lcg_rand(opus_uint32 seed)
{ … }

/* This is a cos() approximation designed to be bit-exact on any platform. Bit exactness
   with this approximation is important because it has an impact on the bit allocation */
opus_int16 bitexact_cos(opus_int16 x)
{ … }

int bitexact_log2tan(int isin,int icos)
{ … }

#ifdef FIXED_POINT
/* Compute the amplitude (sqrt energy) in each of the bands */
void compute_band_energies(const CELTMode *m, const celt_sig *X, celt_ener *bandE, int end, int C, int LM, int arch)
{
   int i, c, N;
   const opus_int16 *eBands = m->eBands;
   (void)arch;
   N = m->shortMdctSize<<LM;
   c=0; do {
      for (i=0;i<end;i++)
      {
         int j;
         opus_val32 maxval=0;
         opus_val32 sum = 0;

         maxval = celt_maxabs32(&X[c*N+(eBands[i]<<LM)], (eBands[i+1]-eBands[i])<<LM);
         if (maxval > 0)
         {
            int shift = celt_ilog2(maxval) - 14 + (((m->logN[i]>>BITRES)+LM+1)>>1);
            j=eBands[i]<<LM;
            if (shift>0)
            {
               do {
                  sum = MAC16_16(sum, EXTRACT16(SHR32(X[j+c*N],shift)),
                        EXTRACT16(SHR32(X[j+c*N],shift)));
               } while (++j<eBands[i+1]<<LM);
            } else {
               do {
                  sum = MAC16_16(sum, EXTRACT16(SHL32(X[j+c*N],-shift)),
                        EXTRACT16(SHL32(X[j+c*N],-shift)));
               } while (++j<eBands[i+1]<<LM);
            }
            /* We're adding one here to ensure the normalized band isn't larger than unity norm */
            bandE[i+c*m->nbEBands] = EPSILON+VSHR32(EXTEND32(celt_sqrt(sum)),-shift);
         } else {
            bandE[i+c*m->nbEBands] = EPSILON;
         }
         /*printf ("%f ", bandE[i+c*m->nbEBands]);*/
      }
   } while (++c<C);
   /*printf ("\n");*/
}

/* Normalise each band such that the energy is one. */
void normalise_bands(const CELTMode *m, const celt_sig * OPUS_RESTRICT freq, celt_norm * OPUS_RESTRICT X, const celt_ener *bandE, int end, int C, int M)
{
   int i, c, N;
   const opus_int16 *eBands = m->eBands;
   N = M*m->shortMdctSize;
   c=0; do {
      i=0; do {
         opus_val16 g;
         int j,shift;
         opus_val16 E;
         shift = celt_zlog2(bandE[i+c*m->nbEBands])-13;
         E = VSHR32(bandE[i+c*m->nbEBands], shift);
         g = EXTRACT16(celt_rcp(SHL32(E,3)));
         j=M*eBands[i]; do {
            X[j+c*N] = MULT16_16_Q15(VSHR32(freq[j+c*N],shift-1),g);
         } while (++j<M*eBands[i+1]);
      } while (++i<end);
   } while (++c<C);
}

#else /* FIXED_POINT */
/* Compute the amplitude (sqrt energy) in each of the bands */
void compute_band_energies(const CELTMode *m, const celt_sig *X, celt_ener *bandE, int end, int C, int LM, int arch)
{ … }

/* Normalise each band such that the energy is one. */
void normalise_bands(const CELTMode *m, const celt_sig * OPUS_RESTRICT freq, celt_norm * OPUS_RESTRICT X, const celt_ener *bandE, int end, int C, int M)
{ … }

#endif /* FIXED_POINT */

/* De-normalise the energy to produce the synthesis from the unit-energy bands */
void denormalise_bands(const CELTMode *m, const celt_norm * OPUS_RESTRICT X,
      celt_sig * OPUS_RESTRICT freq, const opus_val16 *bandLogE, int start,
      int end, int M, int downsample, int silence)
{ … }

/* This prevents energy collapse for transients with multiple short MDCTs */
void anti_collapse(const CELTMode *m, celt_norm *X_, unsigned char *collapse_masks, int LM, int C, int size,
      int start, int end, const opus_val16 *logE, const opus_val16 *prev1logE,
      const opus_val16 *prev2logE, const int *pulses, opus_uint32 seed, int arch)
{ … }

/* Compute the weights to use for optimizing normalized distortion across
   channels. We use the amplitude to weight square distortion, which means
   that we use the square root of the value we would have been using if we
   wanted to minimize the MSE in the non-normalized domain. This roughly
   corresponds to some quick-and-dirty perceptual experiments I ran to
   measure inter-aural masking (there doesn't seem to be any published data
   on the topic). */
static void compute_channel_weights(celt_ener Ex, celt_ener Ey, opus_val16 w[2])
{ … }

static void intensity_stereo(const CELTMode *m, celt_norm * OPUS_RESTRICT X, const celt_norm * OPUS_RESTRICT Y, const celt_ener *bandE, int bandID, int N)
{ … }

static void stereo_split(celt_norm * OPUS_RESTRICT X, celt_norm * OPUS_RESTRICT Y, int N)
{ … }

static void stereo_merge(celt_norm * OPUS_RESTRICT X, celt_norm * OPUS_RESTRICT Y, opus_val16 mid, int N, int arch)
{ … }

/* Decide whether we should spread the pulses in the current frame */
int spreading_decision(const CELTMode *m, const celt_norm *X, int *average,
      int last_decision, int *hf_average, int *tapset_decision, int update_hf,
      int end, int C, int M, const int *spread_weight)
{ … }

/* Indexing table for converting from natural Hadamard to ordery Hadamard
   This is essentially a bit-reversed Gray, on top of which we've added
   an inversion of the order because we want the DC at the end rather than
   the beginning. The lines are for N=2, 4, 8, 16 */
static const int ordery_table[] = …;

static void deinterleave_hadamard(celt_norm *X, int N0, int stride, int hadamard)
{ … }

static void interleave_hadamard(celt_norm *X, int N0, int stride, int hadamard)
{ … }

void haar1(celt_norm *X, int N0, int stride)
{ … }

static int compute_qn(int N, int b, int offset, int pulse_cap, int stereo)
{ … }

struct band_ctx { … };

struct split_ctx { … };

static void compute_theta(struct band_ctx *ctx, struct split_ctx *sctx,
      celt_norm *X, celt_norm *Y, int N, int *b, int B, int B0,
      int LM,
      int stereo, int *fill)
{ … }
static unsigned quant_band_n1(struct band_ctx *ctx, celt_norm *X, celt_norm *Y,
      celt_norm *lowband_out)
{ … }

/* This function is responsible for encoding and decoding a mono partition.
   It can split the band in two and transmit the energy difference with
   the two half-bands. It can be called recursively so bands can end up being
   split in 8 parts. */
static unsigned quant_partition(struct band_ctx *ctx, celt_norm *X,
      int N, int b, int B, celt_norm *lowband,
      int LM,
      opus_val16 gain, int fill)
{ … }


/* This function is responsible for encoding and decoding a band for the mono case. */
static unsigned quant_band(struct band_ctx *ctx, celt_norm *X,
      int N, int b, int B, celt_norm *lowband,
      int LM, celt_norm *lowband_out,
      opus_val16 gain, celt_norm *lowband_scratch, int fill)
{ … }


/* This function is responsible for encoding and decoding a band for the stereo case. */
static unsigned quant_band_stereo(struct band_ctx *ctx, celt_norm *X, celt_norm *Y,
      int N, int b, int B, celt_norm *lowband,
      int LM, celt_norm *lowband_out,
      celt_norm *lowband_scratch, int fill)
{ … }

#ifndef DISABLE_UPDATE_DRAFT
static void special_hybrid_folding(const CELTMode *m, celt_norm *norm, celt_norm *norm2, int start, int M, int dual_stereo)
{ … }
#endif

void quant_all_bands(int encode, const CELTMode *m, int start, int end,
      celt_norm *X_, celt_norm *Y_, unsigned char *collapse_masks,
      const celt_ener *bandE, int *pulses, int shortBlocks, int spread,
      int dual_stereo, int intensity, int *tf_res, opus_int32 total_bits,
      opus_int32 balance, ec_ctx *ec, int LM, int codedBands,
      opus_uint32 *seed, int complexity, int arch, int disable_inv)
{ … }