scal_dec_frame.c

语音压缩算法

/**********************************************************************
MPEG-4 Audio VM
Bit stream module



This software module was originally developed by

Bodo Teichmann (FhG)

and edited by

Bernhard Grill (University of Erlangen)
Takashi koike (Sony Corporation)

in the course of development of the MPEG-2 NBC/MPEG-4 Audio standard
ISO/IEC 13818-7, 14496-1,2 and 3. This software module is an
implementation of a part of one or more MPEG-2 NBC/MPEG-4 Audio tools
as specified by the MPEG-2 NBC/MPEG-4 Audio standard. ISO/IEC gives
users of the MPEG-2 NBC/MPEG-4 Audio standards free license to this
software module or modifications thereof for use in hardware or
software products claiming conformance to the MPEG-2 NBC/ MPEG-4 Audio
standards. Those intending to use this software module in hardware or
software products are advised that this use may infringe existing
patents. The original developer of this software module and his/her
company, the subsequent editors and their companies, and ISO/IEC have
no liability for use of this software module or modifications thereof
in an implementation. Copyright is not released for non MPEG-2
NBC/MPEG-4 Audio conforming products. The original developer retains
full right to use the code for his/her own purpose, assign or donate
the code to a third party and to inhibit third party from using the
code for non MPEG-2 NBC/MPEG-4 Audio conforming products. This
copyright notice must be included in all copies or derivative works.

Copyright (c) 1997.

*/

#include <memory.h>
#include <math.h>
#include <stdio.h>
#include <string.h>
#include <assert.h>

#include "block.h"               /* handler, defines, enums */
#include "buffersHandle.h"       /* handler, defines, enums */
#include "concealmentHandle.h"   /* handler, defines, enums */
#include "mod_bufHandle.h"       /* handler, defines, enums */
#include "monopredHandle.h"      /* handler, defines, enums */
#include "reorderspecHandle.h"   /* handler, defines, enums */
#include "resilienceHandle.h"    /* handler, defines, enums */
#include "tf_mainHandle.h"       /* handler, defines, enums */

#include "all.h"                 /* structs */
#include "bitstreamStruct.h"     /* structs */
#include "monopredStruct.h"      /* structs */
#include "nok_ltp_common.h"      /* structs */
#include "nok_prediction.h"      /* structs */
#include "obj_descr.h"           /* structs */
#include "tf_mainStruct.h"       /* structs */
#include "tns.h"                 /* structs */

#include "dec_lpc.h"


#include "mod_buf.h"
#include "port.h"
#include "flex_mux.h"
#include "lpc_common.h"
#include "dec_tf.h"
#include "bitstream.h"
#include "common_m4a.h"
/* ---  AAC --- */
#include "aac.h"
#include "huffdec2.h"
#include "nok_lt_prediction.h"
#include "scal_dec.h"
#include "plotmtv.h"
#include "util.h"
#include "flex_mux.h"
#include "ntt_conf.h"
#include "ntt_scale_conf.h"
#include "plotmtv.h"
#include "interface.h"
#include "buffers.h"
#include "mp4_tf.h"
/* ***************************************************************************/
/* scalable decoding : bitstream has 3 subframes (called granules) per frame */

static void vcopy( double src[], double dest[], int inc_src, int inc_dest, int vlen )
{
  int i;

  for( i=0; i<vlen-1; i++ ) {
    *dest = *src;
    dest += inc_dest;
    src  += inc_src;
  }
  if (vlen) /* just for bounds-checkers sake */
    *dest = *src;

}

/* compute scalar product of two vectors */
static double scalprod( double src1[], double src2[], 
                        int inc_src1, int inc_src2, int vlen)
{
  int i;
  double sum=0.0;

  for (i=0;i<vlen; i++) {
    sum += (*src1)*(*src2);
    src1 += inc_src1;
    src2 += inc_src2;
  }
  return (sum);
}

static void vmult( double src1[], double src2[], double dest[], 
                   int inc_src1, int inc_src2, int inc_dest, int vlen )
{
  int i;

  for( i=0; i<vlen-1; i++ ) {
    *dest = *src1 * *src2;
    dest += inc_dest;
    src1 += inc_src1;
    src2 += inc_src2;
  }
  if (i<vlen)
    *dest = *src1 * *src2;

}


static void vadd( double src1[], double src2[], double dest[], 
                  int inc_src1, int inc_src2, int inc_dest, int vlen )
{
  int i;

  for( i=0; i<vlen; i++ ) {
    *dest = *src1 + *src2;
    dest += inc_dest;
    src1 += inc_src1;
    src2 += inc_src2;
  }
}

static void vsub( double src1[], double src2[], double dest[], 
                  int inc_src1, int inc_src2, int inc_dest, int vlen )
{
  int i;

  for( i=0; i<vlen; i++ ) {
    *dest = *src1 - *src2;
    dest += inc_dest;
    src1 += inc_src1;
    src2 += inc_src2;
  }
}

static void dec_lowpass(double spectrum[], int lopLong,
                        int lopShort, int maxLine, int iblen, 
                        int windowSequence, int nr_of_sbk)
{
  int bl, block_len, lop, i;
  float slope;
  double zero = 0.0;

  if (windowSequence != EIGHT_SHORT_SEQUENCE) {
    lop = lopLong;
  }
  else {
    lop = lopShort;
  }
    
  block_len = iblen /nr_of_sbk;
  if (lop > maxLine) {
    lop = maxLine;
  }
  slope = (1.0F /(float)lop);
  for (bl=0;bl<nr_of_sbk;bl++){
    vcopy( &zero, &spectrum[bl*block_len+maxLine], 0, 1, block_len - maxLine);
    for (i=1; i<lop; i++) {
      spectrum[bl*block_len+maxLine-i] *= (i*slope);
    }
  }
}

/* get_tns_vm does exactly the same as get_tns in huffdec2.c. Just the
   VM bitstream handling functions replace the AAC-type functions */

static void doInverseMsMatrix(
                       Info       *p_sb_info,
                       double *p_l_spec,
                       double *p_r_spec,
                       int msMask[8][60]
                       )
{
  int sb, win;
  int sfbw; 
  double  tmp_buffer[1024];
  for( win=0; win<p_sb_info->nsbk; win++ ) {
    int sboffs   = win*p_sb_info->bins_per_sbk[win];

    for( sb=0; sb<p_sb_info->sfb_per_sbk[win]; sb++ ) {
      if (p_sb_info->islong==0){
        sfbw = p_sb_info->sfb_width_short[sb];
      }else {
        if (sb==0)
          sfbw = p_sb_info->bk_sfb_top[sb];
        else 
          sfbw = p_sb_info->bk_sfb_top[sb]-p_sb_info->bk_sfb_top[sb-1];        
      }

      if(msMask[win][sb] != 0  ) {
        vadd( &p_l_spec[sboffs], &p_r_spec[sboffs], &tmp_buffer[sboffs],        1, 1, 1, sfbw );  /* -> L */
        vsub( &p_l_spec[sboffs], &p_r_spec[sboffs], &p_r_spec[sboffs], 1, 1, 1, sfbw );  /* -> R */
        vcopy(&tmp_buffer[sboffs], &p_l_spec[sboffs], 1, 1, sfbw );
      }

      sboffs += sfbw;
    }
  }

}

void doMsMatrix(Info *p_sb_info, double *p_l_spec, double *p_r_spec, int msMask[8][60])
{
  int sb, win, i;
  int sfbw;
  double sum[1024];
  double diff[1024];
  for( win=0; win<p_sb_info->nsbk; win++ ) {
    int sboffs   = win*p_sb_info->bins_per_sbk[win];
    
    for( sb=0; sb<p_sb_info->sfb_per_sbk[win]; sb++ ) {
      if (p_sb_info->islong==0){
        sfbw = p_sb_info->sfb_width_short[sb];
      }else {
        if (sb==0)
          sfbw = p_sb_info->bk_sfb_top[sb];
        else 
          sfbw = p_sb_info->bk_sfb_top[sb]-p_sb_info->bk_sfb_top[sb-1];        
      }

      if(msMask[win][sb] != 0  ) {
	vadd(&p_l_spec[sboffs], &p_r_spec[sboffs], &sum[sboffs], 1, 1, 1, sfbw);
	for(i = 0; i < sfbw; i++)
	  p_l_spec[sboffs + i] = 0.5 * sum[sboffs + i];
        
        vsub(&p_l_spec[sboffs], &p_r_spec[sboffs], &diff[sboffs], 1, 1, 1, sfbw);
	for(i = 0; i < sfbw; i++)
	  p_r_spec[sboffs + i] = 0.5 * diff[sboffs + i];
      }
      
      sboffs += sfbw;
    }
  }
  
}

static void  multCoreSpecMsFac(
                        Info       *p_sb_info,
                        int msMask[8][60],
                        double *core_spec,
                        double *out_spec
                        )
{
  int sb, win;
  int sfbw;
  double ms_fac=2;
  for( win=0; win<p_sb_info->nsbk; win++ ) {
    int sboffs   = win*p_sb_info->bins_per_sbk[win];

    for( sb=0; sb<p_sb_info->sfb_per_sbk[win]; sb++ ) {
      if (p_sb_info->islong==0){
        sfbw = p_sb_info->sfb_width_short[sb];
      }else {
        if (sb==0)
          sfbw = p_sb_info->bk_sfb_top[sb];
        else 
          sfbw = p_sb_info->bk_sfb_top[sb]-p_sb_info->bk_sfb_top[sb-1];        
      }
      if( msMask[win][sb] == 0  ) {
        vmult( &core_spec[sboffs], &ms_fac,&out_spec[sboffs] ,1, 0, 1, sfbw );  /* if no ms core = core * fac */
      }else{
        vcopy( &core_spec[sboffs],&out_spec[sboffs] ,1, 1, sfbw );  /* if ms core = core */
      }
      sboffs += sfbw;
    }
  }

}

static int get_tns_vm( BsBitStream *fixed_stream, Info *info, TNS_frame_info *tns_frame_info,int* decoded_bits )
{
  int                       f, t, top, res, res2, compress;
  int                       short_flag, s;
  short                     *sp, tmp, s_mask, n_mask;
  TNSfilt                   *tns_filt;
  TNSinfo                   *tns_info;
  static short              sgn_mask[] = { 
    0x2, 0x4, 0x8     };
  static short              neg_mask[] = { 
    (short) 0xfffc, (short)0xfff8, (short)0xfff0     };
  unsigned long ultmp, numBits;

  short_flag = (!info->islong);
  tns_frame_info->n_subblocks = info->nsbk;

  for (s=0; s<tns_frame_info->n_subblocks; s++) {
    tns_info = &tns_frame_info->info[s];
    numBits = (short_flag ? 1 : 2);
    BsGetBit( fixed_stream, &ultmp,numBits   );
    *decoded_bits += numBits; 
    if (!(tns_info->n_filt = ultmp) )
      continue;     
    BsGetBit( fixed_stream, &ultmp, 1 );
    *decoded_bits += 1; 
    tns_info -> coef_res = res = ultmp + 3;
    top = info->sfb_per_sbk[s];
    tns_filt = &tns_info->filt[ 0 ];
    for (f=tns_info->n_filt; f>0; f--)  {
      tns_filt->stop_band = top;
      numBits = ( short_flag ? 4 : 6);
      BsGetBit( fixed_stream, &ultmp,numBits );
      *decoded_bits += numBits; 
      top = tns_filt->start_band = top - ultmp;

      numBits = ( short_flag ? 3 : 5);
      BsGetBit( fixed_stream, &ultmp, numBits );
      *decoded_bits += numBits; 

      tns_filt->order = ultmp;

      if (tns_filt->order)  {
        BsGetBit( fixed_stream, &ultmp, 1 );
        *decoded_bits += 1; 

        tns_filt->direction = ultmp;
        BsGetBit( fixed_stream, &ultmp, 1 );
        *decoded_bits += 1; 

        compress = ultmp;

        res2 = res - compress;
        s_mask = sgn_mask[ res2 - 2 ];
        n_mask = neg_mask[ res2 - 2 ];

        sp = tns_filt -> coef;
        for (t=tns_filt->order; t>0; t--)  {
          BsGetBit( fixed_stream, &ultmp, res2 );
          *decoded_bits += res2; 
          tmp = ultmp;
          *sp++ = (tmp & s_mask) ? (tmp | n_mask) : tmp;
        }
      }
      tns_filt++;
    }
  }   /* subblock loop */
  return 1;
}

static BsBitBuffer *dynBitBuf;
static int         gran;
static BsBitStream *dyn_stream_read;
int testDebug=0;

void aacScaleableDecodeInit( void )
{
 
  dynBitBuf  = BsAllocBuffer( 64000 );     /* just some large number. For AAC: required ca. 6000 */
  gran = 0;

  dyn_stream_read = BsOpenBufferRead( dynBitBuf );


}

  
static void FSSwitch(
              double  p_core[],
              double  p_rest[], 
              double  p_out[],