ComposerDesktopProject/dev/modify/granula1.c

/*
 * Copyright (c) 1983-2013 Trevor Wishart and Composers Desktop Project Ltd
 * http://www.trevorwishart.co.uk
 * http://www.composersdesktop.com
 *
 This file is part of the CDP System.

    The CDP System 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.

    The CDP System 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 the CDP System; if not, write to the Free Software
    Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
    02111-1307 USA
 *
 */



/*
 *  ABOUT THIS PROCESS
 *
 *  There are (up to) 5 buffers invloved here.....
 *  GRS_SBUF into which the input data is read  from the file.
 *  GRS_BUF  into which the input data is mixed down to mono, where necessary. Otherwise, initial reads go directly to this buffer.
 *      This buffer has an overflow sector of GRS_BUF_SMPXS samples.
 *      The 1st read fills the buffer and the overflow.
 *      After the first read these overflow samples are copied to the bufstart, and a new input buffer start is marked, overflow-samples into the GRS_BUF..
 *  GRS_IBUF is then the point at which further samples are read into the input buffer.
 *  GRS_LBUF is buffer into which grains are copied for processing to the output, (they are timestretched, pshifted or and spliced).
 *  GRS_OBUF is the buffer into which the finished grains are copied ready for output.
 *
 *  GRS_INCHANS is the number of channels in the input grains i.e. after they have (or have not) been mixed down to mono.
 *  GRS_OUTCHANS is the number of channels in the output, which can be
 *      Mono, where no spatial processing takes place, and the input is mono
 *      Multichannel, where spatial processing takes place and the input, is
 *          (a) Mono
 *          (b) A selected (mono) channel from a multichannel input.
 *          (c) A mix down of a multichannel input into a mono source.
 *      Multichannel, where the input is multichannel, and no spatialisation is requested.
 */

/* floatsam version */
#include <stdio.h>
#include <stdlib.h>
#include <limits.h>
#include <string.h>
#include <structures.h>
#include <tkglobals.h>
#include <globcon.h>
#include <processno.h>
#include <modeno.h>
#include <arrays.h>
#include <filetype.h>
#include <modify.h>
#include <cdpmain.h>

#include <sfsys.h>
#include <osbind.h>

//#ifdef unix 
#define round(x) lround((x))
//#endif

#define SAUS_SBUF       (0)
#define SAUS_OBUF       (1)
#define SAUS_BUF(x)     (((x)*2)+2)
#define SAUS_IBUF(x)    (((x)*2)+3)

static int    read_samps_granula(int firsttime,dataptr dz);
static int    granulate(int *thissnd,long *aipc,long *aopc,float **iiiiptr,float **LLLLptr,
                double inv_sr,long *samptotal,float **maxwrite,int *nctr,dataptr dz);
static int    read_a_large_buf(dataptr dz);
static int    read_a_normal_buf_with_wraparound(dataptr dz);
static int    baktrak_granula(long samptotal,int absiicnt_per_chan,float **iiptr,dataptr dz);
static int    reset_granula(int resetskip,dataptr dz);
static int    make_grain(float *b,float **iiptr,float aamp,int gsize_per_chan,double *transpos,dataptr dz);
static int    make_stereo_grain(float *b,float **iiptr,float aamp,int gsize_per_chan,double *transpos,dataptr dz);
static int    write_grain(float **maxwrite,float **Fptr, float **FFptr,int gsize_per_chan,int *nctr,dataptr dz);
static int    write_stereo_grain(double rpos,float **maxwrite,float **Fptr,float **FFptr,
                int gsize_per_chan,int *nctr,dataptr dz);
static double dehole(double pos);
static int    write_samps_granula(long k,int *nctr,dataptr dz);
static void   do_splices(int gsize_per_chan,int bspl,int espl,dataptr dz);
static void   do_btab_splice(dataptr dz);
static void   do_bsplice(int gsize_per_chan,dataptr dz,int bspl);
static void   do_etab_splice(int gsize_per_chan,dataptr dz);
static void   do_esplice(int gsize_per_chan,dataptr dz,int espl);
static void   do_stereo_splices(int gsize_per_chan,int bspl,int espl,dataptr dz);
static void   do_stereo_btab_splice(dataptr dz);
static void   do_stereo_bsplice(int gsize_per_chan,dataptr dz,int bspl);
static void   do_stereo_etab_splice(int gsize_per_chan,dataptr dz);
static void   do_stereo_esplice(int gsize_per_chan,dataptr dz,int espl);
static float  interp_gval_with_amp(float *s,double flcnt_frac,int chans,float ampp);
static float  interp_gval(float *s,double flcnt_frac,int chans);
static int    set_instep(int ostep_per_chan,dataptr dz);
static int    set_outstep(int gsize_per_chan,dataptr dz);
static int    set_range(int absiicnt,dataptr dz);
static long   do_scatter(int ostep_per_chan,dataptr dz);
static int    set_ivalue(int flag,int paramno,int hparamno,int rangeno,dataptr dz);
static double set_dvalue(int flag,int paramno,int hparamno,int rangeno,dataptr dz);
static int    renormalise(int nctr,dataptr dz);

static int  read_samps_sausage(int firsttime,dataptr dz);
static int  read_a_specific_large_buf(int k,dataptr dz);
static int  read_a_specific_normal_buf_with_wraparound(int k,dataptr dz);
static int  baktrak_sausage(int thissnd,long samptotal,int absiicnt_per_chan,float **iiptr,dataptr dz);
static int  reset_sausage(int thissnd,int resetskip,dataptr dz);
static int  get_next_insnd(dataptr dz);
static void perm_sausage(int cnt,dataptr dz);
static void insert(int n,int t,int cnt_less_one,dataptr dz);
static void prefix(int n,int cnt_less_one,dataptr dz);
static void shuflup(int k,int cnt_less_one,dataptr dz);

static int grab_an_appropriate_block_of_sausage_memory(long *this_bloksize,long standard_block,int bufdivisor,dataptr dz);

#ifdef MULTICHAN

static int make_multichan_grain(float *b,float **iiptr,float aamp,int gsize_per_chan,double *transpos,dataptr dz);
static void do_multichan_splices(int gsize_per_chan,int bspl,int espl,dataptr dz);
static void do_multichan_btab_splice(dataptr dz);
static void do_multichan_bsplice(int gsize_per_chan,dataptr dz,int bspl);
static void do_multichan_etab_splice(int gsize_per_chan,dataptr dz);
static void do_multichan_esplice(int gsize_per_chan,dataptr dz,int espl);
static int write_multichan_grain(double rpos,int chan, int chanb,float **maxwrite,float **Fptr,float **FFptr,int gsize_per_chan,int *nctr,dataptr dz);

#endif

/********************************* GRANULA_PROCESS *************************************/

int granula_process(dataptr dz)
{
    int    exit_status;
    int    firsttime = TRUE, thissnd = 0;
    int    nctr = 0;     /* normalisation vals counter */
    long   absicnt_per_chan = 0, absocnt_per_chan = 0;
    float  *iptr = NULL;
    float   *Fptr = dz->fptr[GRS_LBUF];
    long   vals_to_write, total_ssampsread;
    double sr = (double)dz->infile->srate;
    double inverse_sr = 1.0/sr;
    float   *maxwrite = dz->fptr[GRS_LBUF]; /* pointer to last sample created */
//TW AGREED DELETIONS

    if(sloom)
        dz->total_samps_read = 0;
    dz->itemcnt = 0;
    switch(dz->process) {
    case(SAUSAGE):
        if((exit_status = read_samps_sausage(firsttime,dz))<0)
            return(exit_status);
        iptr = dz->sampbuf[SAUS_BUF(thissnd)];
        break;
    case(BRASSAGE):
        if((exit_status = read_samps_granula(firsttime,dz))<0)
            return(exit_status);
        iptr = dz->sampbuf[GRS_BUF];
        break;
    }
    total_ssampsread = dz->ssampsread;  
    display_virtual_time(0L,dz);
    do {
        if((exit_status = granulate(&thissnd,&absicnt_per_chan,&absocnt_per_chan,&iptr,&Fptr,
                                    inverse_sr,&total_ssampsread,&maxwrite,&nctr,dz))<0)
            return(exit_status);
    } while(exit_status==CONTINUE);

    vals_to_write = maxwrite - dz->fptr[GRS_LBUF];
    while(vals_to_write > dz->iparam[GRS_LONGS_BUFLEN]) {
// TW REVISED July 2004
//      if((exit_status = write_samps_granula(dz->buflen,&nctr,dz))<0)
        if((exit_status = write_samps_granula(dz->iparam[GRS_LONGS_BUFLEN],&nctr,dz))<0)
            return(exit_status);
        memmove((char *)dz->fptr[GRS_LBUF],(char *)dz->fptr[GRS_LBUFEND],
            dz->iparam[GRS_LBUF_SMPXS] * sizeof(float));
        memset((char *)dz->fptr[GRS_LBUFMID],0,dz->iparam[GRS_LONGS_BUFLEN] * sizeof(float));
        vals_to_write -= dz->iparam[GRS_LONGS_BUFLEN];
    }
    if(vals_to_write > 0) {
        if((exit_status = write_samps_granula(vals_to_write,&nctr,dz))<0)
            return(exit_status);
    }
    if(dz->total_samps_written <= 0) {
        sprintf(errstr,"SOURCE POSSIBLY TOO SHORT FOR THIS OPTION: Try 'Full Monty'\n");
        return(GOAL_FAILED);
    }
    display_virtual_time(0,dz);
#ifdef MULTICHAN
    dz->infile->channels = dz->iparam[GRS_OUTCHANS];    // setup ONLY NOW for headwrite
#endif
    return renormalise(nctr,dz);
}

/******************************* READ_SAMPS_GRANULA *******************************/

int read_samps_granula(int firsttime,dataptr dz)
{
    int exit_status;
    if(firsttime) {
        if((exit_status = read_a_large_buf(dz))<0)
            return(exit_status);
    } else {
        if((exit_status = read_a_normal_buf_with_wraparound(dz))<0)
            return(exit_status);
    }
    if(firsttime)
        dz->iparam[SAMPS_IN_INBUF] = dz->ssampsread;
    else
        dz->iparam[SAMPS_IN_INBUF] = dz->ssampsread + dz->iparam[GRS_BUF_SMPXS];

    return(FINISHED);
}

/*  INPUT BUFFER :-     
 *
 *  |-----------BUFLEN-----------|
 *
 *  buf      ibuf          bufend
 *  |_________|__________________|buf_smpxs|
 *                              /
 *  |buf_smpxs|            <<-COPY_________/
 *
 *            |-----------BUFLEN-----------|
 */

/***************************** RENORMALISE ****************************
 *
 * (1)  Find smallest normalising factor S (creating gretest level reduction).
 * (2)  For each normalising factor N, find value which will bring it
 *  down to S. That is S/N. Reinsert these values in the normalising
 *  factor array.
 *  REnormalising with these factors, will ensure whole file is normalised
 *  using same factor (S), which is also the smallest factor required.
 * (3)  Seek to start of outfile.
 * (4)  Set infile pointer to same as outfile pointer, so that read_samps()
 *  now reads from OUTFILE.
 * (5)  Reset samps_read counter.
 * (6)  Size of buffers we read depends on whether we output a stereo
 *  file or a mono file.
 * (7)  Reset normalisation-factor array pointer (m).
 *  While we still have a complete buffer to read..
 * (8)  Read samps into output buffer (as, if output is stereo, this
 *  may be larger than ibuf, and will accomodate the data).
 * (9)  Renormalise all values.
 * (10) Increment pointer to normalisation factors.
 * (11) Seek to start of current buffer, in file.
 * (12) Overwrite data in file.
 * (13) Re-seek to end of current buffer, in file.
 * (14) Calcualte how many samps left over at end, and if any...
 * (16) Read last (short) buffer.
 * (17) Set buffer size to actual number of samps left.
 * (18) Renormalise.
 * (19) Seek to start of ACTUAL buffer in file.
 * (20) Write the real number of samps left in buffer.
 * (21) Check the arithmetic.
 * (22) Restore pointer to original infile, so finish() works correctly.
 */
  
int renormalise(int nctr,dataptr dz)
{
    int exit_status;
    long n, m = 0;
//    long total_samps_read = 0;
    long samp_total = dz->total_samps_written, samps_remaining/* , last_total_samps_read*/;
    double min_norm  = dz->parray[GRS_NORMFACT][0]; /* 1 */
    float  *s = NULL;
    double nf;
    long   cnt;

    /* RWD Nov 2 2010: hack to avoid crash! */
    SFPROPS inprops;
    int inchans = 0;
    if(snd_headread(dz->ifd[0],&inprops)){
        inchans = inprops.chans;
    }
    else {
        sprintf(errstr, "WARNING: Can't read infile properties for normalization.\n");
        return SYSTEM_ERROR;
    }
    
//TW NEW MECHANISM writes renormalised vals from original file created (tempfile) into true outfile
    if(sndcloseEx(dz->ifd[0]) < 0) {
        sprintf(errstr, "WARNING: Can't close input soundfile\n");
        return(SYSTEM_ERROR);
    }
    if(sndcloseEx(dz->ofd) < 0) {
        sprintf(errstr, "WARNING: Can't close output soundfile\n");
        return(SYSTEM_ERROR);
    }
    if((dz->ifd[0] = sndopenEx(dz->outfilename,0,CDP_OPEN_RDWR)) < 0) {    /*RWD Nov 2003 need RDWR to enable sndunlink to work */
        sprintf(errstr,"Failure to reopen file %s for renormalisation.\n",dz->outfilename);
        return(SYSTEM_ERROR);
    }
    sndseekEx(dz->ifd[0],0,0);
//  if(!sloom)
//      dz->wordstor[0][strlen(dz->wordstor[0]) -9] = ENDOFSTR;
    if((exit_status = create_sized_outfile(dz->wordstor[0],dz))<0) {
        sprintf(errstr,"Failure to create file %s for renormalisation.\n",dz->wordstor[0]);
        return(exit_status);
    }
    if((exit_status = reset_peak_finder(dz))<0)
        return(exit_status);
    switch(dz->process) {
    case(BRASSAGE): s = dz->sampbuf[GRS_OBUF];  break;
    case(SAUSAGE):  s = dz->sampbuf[SAUS_OBUF]; break;
    }
    dz->total_samps_written = 0;
    for(m=1;m<nctr;m++) {
        if((dz->parray[GRS_NORMFACT])[m] < min_norm)
            min_norm  = (dz->parray[GRS_NORMFACT])[m];
    }

    if(min_norm < 1.0) {
        sprintf(errstr,"Renormalising by %lf\n",min_norm);
        print_outmessage_flush(errstr);
        for(m=0;m<nctr;m++)                             /* 2 */
            (dz->parray[GRS_NORMFACT])[m] = min_norm/(dz->parray[GRS_NORMFACT])[m];
    }
//TW new mechanism: lines not needed
    dz->total_samps_read = 0;                       /* 5 */
    display_virtual_time(0L,dz);                    /* works on dz->total_samps_read here, so param irrelevant */
/* RWD nov 2010 hack, part 2: do this multipLy only if infile is mono */
    if(inchans ==1)
        dz->buflen *= dz->iparam[GRS_OUTCHANS];         /* 6 */
    m = 0;                                          /* 7 */
    cnt = dz->buflen;
    while(dz->total_samps_read + dz->buflen < samp_total) {
        if((exit_status = read_samps(s,dz))<0) {
            close_and_delete_tempfile(dz->outfilename,dz);
            return(exit_status);
        }                                           /* 8 */
 //       total_samps_read += dz->ssampsread;
        if(min_norm < 1.0) {
            nf  = (dz->parray[GRS_NORMFACT])[m];
            for(n=0;n<cnt;n++)                          /* 9 */
                s[n] = /*round*/ (float)((double)s[n] * nf);
            m++;                                        /* 10 */
        }
        if((exit_status = write_samps(s,dz->buflen,dz))<0) {
            close_and_delete_tempfile(dz->outfilename,dz);
            return(exit_status);                    /* 12 */
        }
    }                                               /* 14 */
    if((samps_remaining = samp_total - dz->total_samps_read)>0) {
//        last_total_samps_read =  dz->total_samps_read;
        if((exit_status = read_samps(s,dz))<0) {
            close_and_delete_tempfile(dz->outfilename,dz);
            return(exit_status);                    /* 16 */
        }
        dz->buflen = samps_remaining;   /* 17 */
        if(min_norm < 1.0) {
            nf  = (dz->parray[GRS_NORMFACT])[m];
            for(n=0;n<dz->buflen;n++)                   /* 18 */
                s[n] = /*round*/(float) ((double)s[n] * nf);
        }
        if(samps_remaining > 0) {
            if((exit_status = write_samps(s,samps_remaining,dz))<0) {
                close_and_delete_tempfile(dz->outfilename,dz);
                return(exit_status);                    /* 20 */
            }
        }
    }
    if(dz->total_samps_written != samp_total) {     /* 21 */
        sprintf(errstr,"ccounting problem: Renormalise()\n");
        close_and_delete_tempfile(dz->outfilename,dz);
        return(PROGRAM_ERROR);
    }
    close_and_delete_tempfile(dz->outfilename,dz);
    return(FINISHED);
}

/*************************** GRANULATE *********************************
 * iptr     = advancing base-pointer in input buffer.
 * iiptr    = true read-pointer in input buffer.
 * absicnt_per_chan  = advancing-base-counter in input stream, counting TOTAL samps.
 * absiicnt_per_chan = true counter in input stream, counting TOTAL samps to write pos.
 * Fptr     = advancing base-pointer in output buffer.
 * FFptr    = true write pointer in output buffer.
 * absocnt_per_chan  = advancing-base-counter in output stream, measuring OUTsize.
 */

/* rwd: some major changes here to clear bugs */
/* tw:  some more major changes here to clear implementation errors */

//TW removed redundant 'sr' parameter
int granulate(int *thissnd,long *aipc,long *aopc,float **iiiiptr,float **LLLLptr,
        double inv_sr,long *samptotal,float **maxwrite,int *nctr,dataptr dz)
{
    int exit_status;
    long  absicnt_per_chan = *aipc, absocnt_per_chan = *aopc;
    float *iiptr, *iptr = *iiiiptr, *endbufptr = NULL, *startbufptr = NULL, *thisbuf = NULL;
    float  *FFptr, *Fptr = *LLLLptr;
    long  isauspos, iisauspos;
    float   aamp = -1;
    int   bspl = 0, espl = 0, lastsnd;
    int   firsttime = FALSE;
    int   gsize_per_chan, ostep_per_chan, istep_per_chan, absiicnt_per_chan, rang_per_chan;
    long  smpscat_per_chan;
    int   resetskip = 0;
    double  time = (double)absicnt_per_chan * inv_sr;
    double  transpos = 1.0, position;
    long saved_total_samps_read = 0;
#ifdef MULTICHAN
    int chana, chanb;
#endif
    if((exit_status = read_values_from_all_existing_brktables(time,dz))<0)
        return(exit_status);

    gsize_per_chan = set_ivalue(dz->iparray[GRS_FLAGS][G_GRAINSIZE_FLAG],GRS_GRAINSIZE,GRS_HGRAINSIZE,GRS_GRANGE,dz);

    if(absicnt_per_chan + gsize_per_chan >= dz->iparam[ORIG_SMPSIZE])
        return(FINISHED);

    ostep_per_chan = set_outstep(gsize_per_chan,dz);

    if(dz->iparam[GRS_OUTLEN]>0 && (absocnt_per_chan>=dz->iparam[GRS_OUTLEN]))
        return(FINISHED);   /* IF outfile LENGTH SPECIFIED HAS BEEN MADE: EXIT */

    FFptr = Fptr;
    if(dz->iparray[GRS_FLAGS][G_SCATTER_FLAG])  { /* If grains scattered, scatter FFptr */
        smpscat_per_chan = do_scatter(ostep_per_chan,dz);   
        FFptr += (smpscat_per_chan * dz->iparam[GRS_OUTCHANS]); 
    }
    if(FFptr < dz->fptr[GRS_LBUF]) {
        sprintf(errstr,"Array overrun 1: granula()\n");
        return(PROGRAM_ERROR); /* FFptr can be outside the Lbuffer because Fptr is outside it */
    }
    if(FFptr >= dz->fptr[GRS_LTAILEND]) {
        if((exit_status = write_samps_granula(dz->iparam[GRS_LONGS_BUFLEN],nctr,dz))<0)
            return(exit_status);
/* IF CURRENT POINTER AT END OF LBUF WRITE SAMPS, WRAP AROUND POINTERS */
        memmove((char *)dz->fptr[GRS_LBUF],(char *)dz->fptr[GRS_LBUFEND],
            dz->iparam[GRS_LBUF_SMPXS] * sizeof(float));
        memset((char *)dz->fptr[GRS_LBUFMID],0,dz->iparam[GRS_LONGS_BUFLEN] * sizeof(float));
        FFptr    -= dz->iparam[GRS_LONGS_BUFLEN];   
        if((Fptr -= dz->iparam[GRS_LONGS_BUFLEN])  < dz->fptr[GRS_LBUF]) {
            sprintf(errstr,"Array overrun 2: granula()\n");
            return(PROGRAM_ERROR);
        }
        *maxwrite -= dz->iparam[GRS_LONGS_BUFLEN];
    }

    istep_per_chan    = set_instep(ostep_per_chan,dz);
    if(istep_per_chan==0 && dz->iparam[GRS_OUTLEN]==0) {
        sprintf(errstr,"velocity or instep has become so small that file will be infinitely long!!\n"
                       "Try slightly increasing your very small values.\n");
        return(GOAL_FAILED);
    }
    iiptr    = iptr;

    if(dz->process==SAUSAGE) {
        lastsnd   = *thissnd;
        isauspos  = iptr  - dz->sampbuf[SAUS_BUF(lastsnd)];
        iisauspos = iiptr - dz->sampbuf[SAUS_BUF(lastsnd)];
        *thissnd  = get_next_insnd(dz);
        iiptr     = dz->sampbuf[SAUS_BUF(*thissnd)] + iisauspos;
        iptr      = dz->sampbuf[SAUS_BUF(*thissnd)] + isauspos;
    }

    absiicnt_per_chan = absicnt_per_chan;
    if(dz->iparray[GRS_FLAGS][G_RANGE_FLAG]) {
        rang_per_chan      = set_range(absiicnt_per_chan,dz);       /* RESET iiptr etc WITHIN SEARCHRANGE */
        absiicnt_per_chan -= rang_per_chan;
        iiptr             -= rang_per_chan * dz->iparam[GRS_INCHANS];
    }
    switch(dz->process) {
    case(BRASSAGE):
        endbufptr   = dz->sbufptr[GRS_BUF];
        startbufptr = dz->sampbuf[GRS_BUF];
        break;
    case(SAUSAGE):
        endbufptr   = dz->sbufptr[SAUS_BUF(*thissnd)];
        startbufptr = dz->sampbuf[SAUS_BUF(*thissnd)];
        break;
    }
    if(iiptr >= endbufptr) {
        while(iiptr >= endbufptr) {
            switch(dz->process) {
            case(BRASSAGE):
                if((read_samps_granula(firsttime,dz))<0)                    /* IF iiptr OFF END OF IBUF */
                    return(exit_status);
                break;
            case(SAUSAGE):
                if((read_samps_sausage(firsttime,dz))<0)                    /* IF iiptr OFF END OF IBUF */
                    return(exit_status);
                break;
            }
            *samptotal += dz->ssampsread;
            if(dz->ssampsread<=0)
                return(FINISHED);
                    /* READ SAMPS, WRAP BACK POINTER */
            iiptr -= dz->buflen;
            iptr  -= dz->buflen;
        }
    } else if(iiptr < startbufptr) {                                /* IF RANGE TAKES US BAK OUT OF THIS BUF, */

        if(sloom)
            saved_total_samps_read = dz->total_samps_read;  /* saved so display_virtual_time() works during baktrak!! */
        if((resetskip = *samptotal - dz->iparam[SAMPS_IN_INBUF])<0) {   /* SET RESETSKIP TO START OF CURRENT BUFFER */
            sprintf(errstr,"Error in baktraking: granula()\n");
            return(PROGRAM_ERROR);
        }
        switch(dz->process) {
        case(BRASSAGE):
            if((exit_status = baktrak_granula(*samptotal,absiicnt_per_chan,&iiptr,dz))<0)
                return(exit_status);                                    /* SEEK BACKWDS, & RESET iiptr In NEW BUF */
            break;
        case(SAUSAGE):
            if((exit_status = baktrak_sausage(*thissnd,*samptotal,absiicnt_per_chan,&iiptr,dz))<0)
                return(exit_status);                                    /* SEEK BACKWDS, & RESET iiptr In NEW BUF */
            break;
        }
        if(sloom)
            dz->total_samps_read = saved_total_samps_read;      /* restore so its not changed by the baktraking!! */
    }
    if(dz->iparray[GRS_FLAGS][G_AMP_FLAG])
        /* RWD was set_ivalue*/
        aamp = (float) set_dvalue(dz->iparray[GRS_FLAGS][G_AMP_FLAG],GRS_AMP,GRS_HAMP,GRS_ARANGE,dz);
                                    /* GET SPLICE VALUES */
    bspl = set_ivalue(dz->iparray[GRS_FLAGS][G_BSPLICE_FLAG],GRS_BSPLICE,GRS_HBSPLICE,GRS_BRANGE,dz);
    espl = set_ivalue(dz->iparray[GRS_FLAGS][G_ESPLICE_FLAG],GRS_ESPLICE,GRS_HESPLICE,GRS_ERANGE,dz);
    switch(dz->process) {
    case(BRASSAGE): thisbuf = dz->sampbuf[GRS_BUF];                 break;
    case(SAUSAGE):  thisbuf = dz->sampbuf[SAUS_BUF(*thissnd)];      break;
    }

#ifndef MULTICHAN

    switch(dz->iparam[GRS_INCHANS]) {
    case(1):
        if(!make_grain(thisbuf,&iiptr,aamp,gsize_per_chan,&transpos,dz))    
            return(FINISHED);                                       /* COPYGRAIN TO GRAINBUF,INCLUDING ANY PSHIFT */
        do_splices(gsize_per_chan,bspl,espl,dz);                    /* DO SPLICES IN GRAINBUF */
        break;
    case(2):
        if(!make_stereo_grain(thisbuf,&iiptr,aamp,gsize_per_chan,&transpos,dz)) 
            return(FINISHED);                                       /* COPYGRAIN TO GRAINBUF,INCLUDING ANY PSHIFT */
        do_stereo_splices(gsize_per_chan,bspl,espl,dz);             /* DO SPLICES IN GRAINBUF */
        break;
    }
#else

    if(!make_multichan_grain(thisbuf,&iiptr,aamp,gsize_per_chan,&transpos,dz))  
        return(FINISHED);                                           /* COPYGRAIN TO GRAINBUF,INCLUDING ANY PSHIFT */
        do_multichan_splices(gsize_per_chan,bspl,espl,dz);          /* DO SPLICES IN GRAINBUF */

#endif

    if(dz->iparray[GRS_FLAGS][G_SPACE_FLAG]) {      /* IF SPATIAL INFO, GET IT,WRITE STEREO GRAIN */
        position = set_dvalue(dz->iparray[GRS_FLAGS][G_SPACE_FLAG],GRS_SPACE,GRS_HSPACE,GRS_SPRANGE,dz);
#ifndef MULTICHAN
        if((exit_status = write_stereo_grain(position,maxwrite,&Fptr,&FFptr,gsize_per_chan,nctr,dz))<0)
            return(exit_status);
#else
        if(dz->out_chans > 2) {
            chana = (int)floor(position);
            position  -= (double)chana; //  position is relative position between 2 adjacent out-chans
            chanb = chana + 1;          //  chanb is adjacent to chana
            if(chana > dz->out_chans)   //  chana beyond last lspkr wraps around to 1st lspkr
                chana = 1;
            else if(chana < 1)          //  chana below 1st loudspeaker wraps around to last-lspkr
                chana = dz->out_chans;
            if((exit_status = write_multichan_grain(position,chana,chanb,maxwrite,&Fptr,&FFptr,gsize_per_chan,nctr,dz))<0)
                return(exit_status);
        } else {
            if((exit_status = write_stereo_grain(position,maxwrite,&Fptr,&FFptr,gsize_per_chan,nctr,dz))<0)
                return(exit_status);
        }
#endif
    } else {            /* WRITE GRAIN */
        if((exit_status = write_grain(maxwrite,&Fptr,&FFptr,gsize_per_chan,nctr,dz))<0)
            return(exit_status);
    }
    if(sloom)
        saved_total_samps_read = dz->total_samps_read;  /* saved so not disturbed by restoring of baktrakd-from buffer */

    switch(dz->process) {
    case(BRASSAGE):                                             /* IF BAKTRAKD : RESTORE ORIGINAL BUFFER */
        if(resetskip && (exit_status = reset_granula(resetskip,dz))<0)  
            return(exit_status);
        break;
    case(SAUSAGE):
        if(resetskip && (exit_status = reset_sausage(*thissnd,resetskip,dz))<0)
            return(exit_status);
        break;
    }
    if(sloom)
        dz->total_samps_read = saved_total_samps_read;
#ifndef MULTICHAN
    iptr    += istep_per_chan;      /* MOVE FORWARD IN INFILE */
    if(dz->iparam[GRS_INCHANS]==STEREO)
        iptr    += istep_per_chan;          /* move further if using STEREO INPUT DATA */
#else
    iptr += (istep_per_chan * dz->iparam[GRS_INCHANS]);     /* MOVE FORWARD IN postmixdown input-buffer, which is either MONO or multichannel */
#endif
    absicnt_per_chan += istep_per_chan;     /* rwd: moved here from top of input section */

#ifndef MULTICHAN
    Fptr    += ostep_per_chan;              /* Fptr may still be outside (bottom of) Lbuf */
    if(dz->iparray[GRS_FLAGS][G_SPACE_FLAG] || dz->iparam[GRS_INCHANS]==STEREO)
        Fptr += ostep_per_chan; /* Advance by stereo step, for STEREO OUTPUT */
#else
    Fptr += ostep_per_chan * dz->iparam[GRS_OUTCHANS];  /* Move forward in output buffer, which can be mono, spatialised-stereo or multichannel */
#endif

    /*      so we don't lose first grain */
    absocnt_per_chan += ostep_per_chan;

    *aipc = absicnt_per_chan;   /* RETURN VALUES OF RETAINED VARIABLES */
    *aopc = absocnt_per_chan;
    *iiiiptr = iptr;
    *LLLLptr = Fptr;
    return(CONTINUE);
}

/*************************** BAKTRAK_GRANULA ******************************
 *
 *     <------------ baktrak(b) ---------------->
 *
 *     <--(b-x)-->
 *                <------------ x -------------->
 *               |-------- current bufer --------|
 *
 *     |-------- new buffer --------|
 *      <------------x------------->
 *              
 */

#ifndef MULTICHAN

int baktrak_granula(long samptotal,int absiicnt_per_chan,float **iiptr,dataptr dz)
{
    int  exit_status;
    long bktrk, new_position;
    unsigned long reset_size = dz->buflen + dz->iparam[GRS_BUF_SMPXS];

    bktrk = samptotal - (absiicnt_per_chan * dz->iparam[GRS_INCHANS]);
//TW I agree, this is FINE!!, and, with sndseekEx, algo is more efficient
//  whenever the search-range is relatively small (and equally efficient otherwise)
    *iiptr      = dz->sampbuf[GRS_BUF];

    if((new_position = samptotal - bktrk)<0) {
        fprintf(stdout,"WARNING: Non-fatal program error:\nRange arithmetic problem - 2, in baktraking.\n");
        fflush(stdout);
        new_position = 0;
        *iiptr = dz->sampbuf[GRS_BUF];
    }
    if(dz->iparam[GRS_CHAN_TO_XTRACT])   /* IF we've converted from STEREO file */
        new_position *= 2;
    if(sndseekEx(dz->ifd[0],new_position,0)<0) {
        sprintf(errstr,"sndseekEx error: baktrak_granula()\n");
        return(SYSTEM_ERROR);
    }
    memset((char *)dz->sampbuf[GRS_BUF],0,reset_size * sizeof(float));
    if(dz->iparam[GRS_CHAN_TO_XTRACT]) {
        reset_size *= 2;
        memset((char *)dz->sampbuf[GRS_SBUF],0,reset_size * sizeof(float));
    }
    if((exit_status = read_a_large_buf(dz))<0)
        return(exit_status);
    dz->iparam[SAMPS_IN_INBUF] = dz->ssampsread;
    return(FINISHED);
}

#else

int baktrak_granula(long samptotal,int absiicnt_per_chan,float **iiptr,dataptr dz)
{
    int  exit_status,  chans = dz->infile->channels;
    long bktrk, new_position;
    unsigned long reset_size = dz->buflen + dz->iparam[GRS_BUF_SMPXS];

    bktrk = samptotal - (absiicnt_per_chan * dz->iparam[GRS_INCHANS]);
//TW I agree, this is FINE!!, and, with sndseekEx, algo is more efficient
//  whenever the search-range is relatively small (and equally efficient otherwise)
    *iiptr      = dz->sampbuf[GRS_BUF];

    if((new_position = samptotal - bktrk)<0) {
        fprintf(stdout,"WARNING: Non-fatal program error:\nRange arithmetic problem - 2, in baktraking.\n");
        fflush(stdout);
        new_position = 0;
        *iiptr = dz->sampbuf[GRS_BUF];
    }
    if(dz->iparam[GRS_CHAN_TO_XTRACT])   /* IF we've converted from STEREO file */
        new_position *= chans;
    if(sndseekEx(dz->ifd[0],new_position,0)<0) {
        sprintf(errstr,"sndseekEx error: baktrak_granula()\n");
        return(SYSTEM_ERROR);
    }
    memset((char *)dz->sampbuf[GRS_BUF],0,reset_size * sizeof(float));
    if(dz->iparam[GRS_CHAN_TO_XTRACT]) {
        reset_size *= chans;
        memset((char *)dz->sampbuf[GRS_SBUF],0,reset_size * sizeof(float));
    }
    if((exit_status = read_a_large_buf(dz))<0)
        return(exit_status);
    dz->iparam[SAMPS_IN_INBUF] = dz->ssampsread;
    return(FINISHED);
}

#endif

/*************************** READ_A_LARGE_BUF ******************************/

#ifndef MULTICHAN

int read_a_large_buf(dataptr dz)
{
    int exit_status;
    long n, m, k;
    dz->buflen += dz->iparam[GRS_BUF_SMPXS];
    if(dz->iparam[GRS_CHAN_TO_XTRACT]) {
        dz->buflen *= 2;
        if((exit_status = read_samps(dz->sampbuf[GRS_SBUF],dz))<0)
            return(exit_status);
        dz->buflen /= 2;
        dz->ssampsread /= 2;
        switch(dz->iparam[GRS_CHAN_TO_XTRACT]) {
        case(1):
            for(n=0,m=0;n<dz->ssampsread;n++,m+=2)
            (dz->sampbuf[GRS_BUF])[n] = (dz->sampbuf[GRS_SBUF])[m];
            break;
        case(2):
            for(n=0,m=1;n<dz->ssampsread;n++,m+=2)
                (dz->sampbuf[GRS_BUF])[n] = (dz->sampbuf[GRS_SBUF])[m];
            break;
        case(BOTH_CHANNELS):
            for(n=0,m=0,k=1;n<dz->ssampsread;n++,m+=2,k+=2)
                (dz->sampbuf[GRS_BUF])[n] = (float)(((dz->sampbuf[GRS_SBUF])[m] + (dz->sampbuf[GRS_SBUF])[k]) * 0.5f);
            break;
        }
    } else {
        if((exit_status = read_samps(dz->sampbuf[GRS_BUF],dz))<0)
            return(exit_status);
    }
    dz->buflen -= dz->iparam[GRS_BUF_SMPXS];
    return(FINISHED);
}

#else

int read_a_large_buf(dataptr dz)
{
    int exit_status;
    long n, m, ibufcnt;
    int chans = dz->infile->channels;
    double sum;
    if(dz->iparam[GRS_CHAN_TO_XTRACT]) {
        dz->buflen += dz->iparam[GRS_BUF_SMPXS];
        dz->buflen *= chans;
        if((exit_status = read_samps(dz->sampbuf[GRS_SBUF],dz))<0)
            return(exit_status);
        dz->buflen /= chans;
        dz->buflen -= dz->iparam[GRS_BUF_SMPXS];
        dz->ssampsread /= chans;
        switch(dz->iparam[GRS_CHAN_TO_XTRACT]) {
        case(ALL_CHANNELS):
            ibufcnt = 0;
            for(n=0;n<dz->ssampsread;n++) {
                sum = 0.0;
                for(m=0;m<chans;m++)
                    sum += dz->sampbuf[GRS_SBUF][ibufcnt++];
                dz->sampbuf[GRS_BUF][n] = (float)(sum/(double)chans);
            }
            break;
        default:
            for(n=0,m=dz->iparam[GRS_CHAN_TO_XTRACT];n<dz->ssampsread;n++,m+=chans)
                dz->sampbuf[GRS_BUF][n] = dz->sampbuf[GRS_SBUF][m];
            break;
        }
    } else {
        dz->buflen += dz->iparam[GRS_BUF_SMPXS];
        if((exit_status = read_samps(dz->sampbuf[GRS_BUF],dz))<0)
            return(exit_status);
        dz->buflen -= dz->iparam[GRS_BUF_SMPXS];
    }
    return(FINISHED);
}

#endif

/*************************** READ_A_NORMAL_BUF_WITH_WRAPAROUND ******************************/

#ifndef MULTICHAN

int read_a_normal_buf_with_wraparound(dataptr dz)
{
    int exit_status;
    long n,m,k;
    memmove((char *)dz->sampbuf[GRS_BUF],(char *)(dz->sbufptr[GRS_BUF]),
        dz->iparam[GRS_BUF_SMPXS] * sizeof(float));
    if(dz->iparam[GRS_CHAN_TO_XTRACT]) {
        dz->buflen *= 2;
        if((exit_status = read_samps(dz->sampbuf[GRS_SBUF],dz))<0)
            return(exit_status);
        dz->buflen /= 2;
        dz->ssampsread  /= 2;
        switch(dz->iparam[GRS_CHAN_TO_XTRACT]) {
        case(1):
            for(n=0,m=0;n<dz->ssampsread;n++,m+=2)
                (dz->sampbuf[GRS_IBUF])[n] = (dz->sampbuf[GRS_SBUF])[m];
            break;
        case(2):
            for(n=0,m=1;n<dz->ssampsread;n++,m+=2)
                (dz->sampbuf[GRS_IBUF])[n] = (dz->sampbuf[GRS_SBUF])[m];
            break;
        case(BOTH_CHANNELS):
            for(n=0,m=0,k=1;n<dz->ssampsread;n++,m+=2,k+=2)
                (dz->sampbuf[GRS_IBUF])[n] = (float)(((dz->sampbuf[GRS_SBUF])[m] + (dz->sampbuf[GRS_SBUF])[k]) * 0.5f);
            break;
        }
    } else {
        if((exit_status = read_samps(dz->sampbuf[GRS_IBUF],dz))<0)
            return(exit_status);
    }
    return(FINISHED);
}

#else

int read_a_normal_buf_with_wraparound(dataptr dz)
{
    int exit_status;
    long n,m,ibufcnt;
    double sum;
    int chans = dz->infile->channels;
    memmove((char *)dz->sampbuf[GRS_BUF],(char *)(dz->sbufptr[GRS_BUF]),
        dz->iparam[GRS_BUF_SMPXS] * sizeof(float));
    if(dz->iparam[GRS_CHAN_TO_XTRACT]) {
        dz->buflen *= chans;
        if((exit_status = read_samps(dz->sampbuf[GRS_SBUF],dz))<0)
            return(exit_status);
        dz->buflen /= chans;
        dz->ssampsread  /= chans;
        switch(dz->iparam[GRS_CHAN_TO_XTRACT]) {
        case(ALL_CHANNELS):
            ibufcnt = 0;
            for(n=0;n<dz->ssampsread;n++) {
                sum = 0.0;
                for(m=0;m<chans;m++)
                    sum += dz->sampbuf[GRS_SBUF][ibufcnt++];
                dz->sampbuf[GRS_IBUF][n] = (float)(sum/(double)chans);
            }
            break;
        default:
            for(n=0,m=dz->iparam[GRS_CHAN_TO_XTRACT];n<dz->ssampsread;n++,m+=chans)
                dz->sampbuf[GRS_IBUF][n] = dz->sampbuf[GRS_SBUF][m];
            break;
        }
    } else {
        if((exit_status = read_samps(dz->sampbuf[GRS_IBUF],dz))<0)
            return(exit_status);
    }
    return(FINISHED);
}

#endif

/****************************** RESET_GRANULA *******************************/

#ifndef MULTICHAN

int reset_granula(int resetskip,dataptr dz)
{
    unsigned long reset_size = dz->buflen + dz->iparam[GRS_BUF_SMPXS];

    memset((char *)dz->sampbuf[GRS_BUF],0,reset_size * sizeof(float));
    if(dz->iparam[GRS_CHAN_TO_XTRACT]) {
        reset_size *= 2;
        memset((char *)dz->sampbuf[GRS_SBUF],0,reset_size * sizeof(float));
    }
    if(dz->iparam[GRS_CHAN_TO_XTRACT]) /* If we've converted from a multichannel file */
        resetskip *= 2;
    if(sndseekEx(dz->ifd[0],resetskip,0)<0) {
        sprintf(errstr,"sndseek error: reset_granula()\n");
        return(SYSTEM_ERROR);
    }
    return read_a_large_buf(dz);
}

#else

int reset_granula(int resetskip,dataptr dz)
{
    unsigned long reset_size = dz->buflen + dz->iparam[GRS_BUF_SMPXS];

    memset((char *)dz->sampbuf[GRS_BUF],0,reset_size * sizeof(float));
    if(dz->iparam[GRS_CHAN_TO_XTRACT]) {
        reset_size *= dz->infile->channels;
        memset((char *)dz->sampbuf[GRS_SBUF],0,reset_size * sizeof(float));
    }
    if(dz->iparam[GRS_CHAN_TO_XTRACT]) /* If we've converted from a multichannel file */
        resetskip *= dz->infile->channels;
    if(sndseekEx(dz->ifd[0],resetskip,0)<0) {
        sprintf(errstr,"sndseek error: reset_granula()\n");
        return(SYSTEM_ERROR);
    }
    return read_a_large_buf(dz);
}

#endif

/************************** DO_SPLICES *****************************/

void do_splices(int gsize_per_chan,int bspl,int espl,dataptr dz)
{
    if(dz->iparam[GRS_IS_BTAB] && (dz->iparam[GRS_BSPLICE] < gsize_per_chan/2))
        do_btab_splice(dz);
    else
        do_bsplice(gsize_per_chan,dz,bspl);
    if(dz->iparam[GRS_IS_ETAB] && (dz->iparam[GRS_ESPLICE] < gsize_per_chan/2))
        do_etab_splice(gsize_per_chan,dz);
    else
        do_esplice(gsize_per_chan,dz,espl);
}

/************************** DO_BTAB_SPLICE ****************************/

void do_btab_splice(dataptr dz)
{
    long n, k = dz->iparam[GRS_BSPLICE];
    double *d;
    float *gbufptr = dz->extrabuf[GRS_GBUF];   
    if(k==0)
        return;
    d = dz->parray[GRS_BSPLICETAB];
    for(n=0;n<k;n++) {
        *gbufptr = (float)/*round*/(*gbufptr * *d); 
        gbufptr++;
        d++;
    }
}

/************************** DO_BSPLICE ****************************
 *
 * rwd: changed to avoid f/p division, added exponential option
 */
void do_bsplice(int gsize_per_chan,dataptr dz,int bspl)
{
    double dif,val,lastval,length,newsum,lastsum,twodif;
    long n, k = min(bspl,gsize_per_chan);
    float *gbufptr = dz->extrabuf[GRS_GBUF];
    if(k==0)
        return;
    val = 0.0;
    length = (double)k;
    if(!dz->vflag[GRS_EXPON]){
        dif = 1.0/length;
        lastval = dif;
        *gbufptr++ = (float)val;
        *gbufptr = (float)/*round*/(*gbufptr * lastval);
        gbufptr++;   
        for(n=2;n<k;n++) {
            val = lastval + dif;
            lastval = val;
            *gbufptr = (float) /*round*/(*gbufptr * val);
            gbufptr++;
        }
    } else {            /* fast quasi-exponential */
        dif = 1.0/(length*length);
        twodif = dif * 2.0;
        lastsum = 0.0;
        lastval = dif;
        *gbufptr++ = (float)val;
        *gbufptr = (float) /*round*/(*gbufptr * lastval);   
        gbufptr++;
        for(n=2;n<k;n++) {
            newsum = lastsum + twodif;
            val = lastval + newsum + dif;
            *gbufptr = (float) /*round*/(*gbufptr * val);
            gbufptr++;
            lastval = val;
            lastsum = newsum;
        }
    }
}

/************************** DO_ETAB_SPLICE ****************************/

void do_etab_splice(int gsize_per_chan,dataptr dz)
{
    long n, k = (long)dz->iparam[GRS_ESPLICE];
    double *d;
    float *gbufptr = dz->extrabuf[GRS_GBUF] + gsize_per_chan - k;   
    if(k==0)
        return;
    d = dz->parray[GRS_ESPLICETAB];
    for(n=0;n<k;n++) {
        *gbufptr = (float) /*round*/(*gbufptr * *d); 
        gbufptr++;
        d++;
    }
}

/************************** DO_ESPLICE ****************************/
/* rwd: changed to avoid f/p division, added exponential option */

void do_esplice(int gsize_per_chan,dataptr dz,int espl)
{
    double dif,val,lastval,length,newsum,lastsum,twodif;
    long n, k = min(espl,gsize_per_chan);
    float *gbufptr = dz->extrabuf[GRS_GBUF] + gsize_per_chan;
    if(k==0)
        return;
    val = 0.0;
    length = (double) k;
    if(!dz->vflag[GRS_EXPON]) {
        dif = 1.0/length;
        lastsum = dif;
        *--gbufptr = (float)val;
        gbufptr--;
        *gbufptr = (float) /*round*/(*gbufptr * lastsum);
        for(n=k-3;n>=0;n--) {
            val = lastsum + dif;
            lastsum = val;
            gbufptr--;
            *gbufptr = (float) /*round*/(*gbufptr * val);
        }
    } else {            /* fast quasi-exponential */ 
        dif = 1.0/(length * length);
        twodif = dif * 2.0;
        lastsum = 0.0;
        lastval = dif;
        *--gbufptr = (float)val;
        gbufptr--;
        *gbufptr = (float) /*round*/(*gbufptr * lastval);
        for(n=k-3;n>=0;n--) {
            newsum =lastsum + twodif;
            val = lastval + newsum + dif;
            gbufptr--;
            *gbufptr = (float) /*round*/ (*gbufptr * val);
            lastval = val;
            lastsum = newsum;
        }
    }
}

/***************************** MAKE_GRAIN ***************************
 * iicnt = RELATIVE read-pointer in input buffer.
 */

int make_grain(float *b,float **iiptr,float aamp,int gsize_per_chan,double *transpos,dataptr dz)
{                       /* rwd: added interpolation option */
    long n,real_gsize = gsize_per_chan;
    double flcnt;
    long iicnt;
    double flcnt_frac;
    float *s = *iiptr, *gbufptr = dz->extrabuf[GRS_GBUF];

    if(aamp>=0) {
        if(!dz->iparray[GRS_FLAGS][G_PITCH_FLAG]) {
            if(real_gsize >= (long)dz->iparam[SAMPS_IN_INBUF])    /* JUNE 1996 */
                return(0);
            for(n=0;n<real_gsize;n++)  /* COPY GRAIN TO GRAINBUF & RE-LEVEL ETC */
                *gbufptr++ = (float)(*s++ * aamp);
        } else {
            iicnt = s - b;
            *transpos = set_dvalue(dz->iparray[GRS_FLAGS][G_PITCH_FLAG],GRS_PITCH,GRS_HPITCH,GRS_PRANGE,dz);
            *transpos = pow(2.0,*transpos);
            if((int)(real_gsize * (*transpos))+1+iicnt >= dz->iparam[SAMPS_IN_INBUF])     /* JUNE 1996 */
                return(0);
            flcnt = (double)iicnt;
            if(!dz->vflag[GRS_NO_INTERP]){
                flcnt_frac = flcnt - (double)iicnt;
                for(n=0;n<real_gsize;n++) {
                    *gbufptr++ = interp_gval_with_amp(s,flcnt_frac,dz->iparam[GRS_INCHANS],aamp);
                    flcnt += *transpos;  
                    iicnt = (long)flcnt;
                    s = b + iicnt;
                    flcnt_frac = flcnt - (double) iicnt;
                }
            } else {            /* do truncate as originally */
                for(n=0;n<real_gsize;n++){
                    *gbufptr++ = (float)(*s * aamp);
                    flcnt += *transpos;
                    iicnt = round(flcnt);
                    s     = b + iicnt;
                }
            }   
        }
    } else {        /* NO CHANGE IN AMPLITUDE */
        if(!dz->iparray[GRS_FLAGS][G_PITCH_FLAG]) {
            if(real_gsize >= dz->iparam[SAMPS_IN_INBUF])      /* JUNE 1996 */
                return(0);
            for(n=0;n<real_gsize;n++)
                *gbufptr++ = *s++;
        } else {
            iicnt = s - b;
            *transpos = set_dvalue(dz->iparray[GRS_FLAGS][G_PITCH_FLAG],GRS_PITCH,GRS_HPITCH,GRS_PRANGE,dz);
            *transpos = pow(2.0,*transpos);
            if((int)(real_gsize * (*transpos))+1+iicnt >= dz->iparam[SAMPS_IN_INBUF])     /* JUNE 1996 */
                return(0);
            flcnt = (double)iicnt;
            if(dz->vflag[GRS_NO_INTERP]){     /* do truncate as originally */
                for(n=0;n<gsize_per_chan;n++){
                    *gbufptr++ = *s;
                    flcnt += *transpos;
                    iicnt = round(flcnt);
                    s = b + iicnt;
                }
            } else {            
                flcnt_frac = flcnt - (double)iicnt;
                for(n=0;n<real_gsize;n++) {
                    *gbufptr++ = interp_gval(s,flcnt_frac,dz->iparam[GRS_INCHANS]);
                    flcnt += *transpos;  
                    iicnt = (long)flcnt;
                    s = b + iicnt;
                    flcnt_frac = flcnt - (double)iicnt;
                }
            }   
        }
    }
    *iiptr = s;
    return(1);
}

/***************************** MAKE_STEREO_GRAIN ***************************
 * iicnt = RELATIVE read-pointer in input buffer (starts at 0).
 */

int make_stereo_grain(float *b,float **iiptr,float aamp,int gsize_per_chan,double *transpos,dataptr dz)
{
    long n;
    double flcnt;
    long iicnt, real_gsize = gsize_per_chan * 2;
    double flcnt_frac;
    float *s = *iiptr, *gbufptr = dz->extrabuf[GRS_GBUF];
    if(aamp>=0) {
        if(!dz->iparray[GRS_FLAGS][G_PITCH_FLAG]) {
            if(real_gsize >= dz->iparam[SAMPS_IN_INBUF])      /* JUNE 1996 */
                return(0);
            for(n=0;n<real_gsize;n++)   /* COPY GRAIN TO GRAINBUF & RE-LEVEL ETC */
                *gbufptr++ = (*s++ * aamp);
        } else {
            iicnt = (s - b)/2;
            *transpos = set_dvalue(dz->iparray[GRS_FLAGS][G_PITCH_FLAG],GRS_PITCH,GRS_HPITCH,GRS_PRANGE,dz);
            *transpos = pow(2.0,*transpos);
            if((((int)(gsize_per_chan * *transpos)+1) + iicnt) * 2 >= dz->iparam[SAMPS_IN_INBUF])     /* JUNE 1996 */
                return(0);
            flcnt = (double)iicnt;
            if(dz->vflag[GRS_NO_INTERP]){  /* do truncate as originally */
                for(n=0;n<gsize_per_chan;n++){
                    *gbufptr++ = (*s * aamp);
                    s++;
                    *gbufptr++ = (*s * aamp);
                    flcnt += *transpos;
                    iicnt = round(flcnt);
                    s = b + (iicnt * 2);
                }
            } else {
                flcnt_frac = flcnt - (double)iicnt;
                for(n=0;n<gsize_per_chan;n++) {
                    *gbufptr++ = interp_gval_with_amp(s,flcnt_frac,dz->iparam[GRS_INCHANS],aamp);
                    s++;
                    *gbufptr++ = interp_gval_with_amp(s,flcnt_frac,dz->iparam[GRS_INCHANS],aamp);
                    flcnt += *transpos;  
                    iicnt = (long)flcnt;
                    s = b + (iicnt * 2);
                    flcnt_frac = flcnt - (double) iicnt;
                }
            }
        }
    } else {        /* NO CHANGE IN AMPLITUDE */
        if(!dz->iparray[GRS_FLAGS][G_PITCH_FLAG]) {
            if(real_gsize >= dz->iparam[SAMPS_IN_INBUF])      /* JUNE 1996 */
                return(0);
            for(n=0;n<real_gsize;n++)
                *gbufptr++ = *s++;
        } else {
            iicnt = (s - b)/2;
            *transpos = set_dvalue(dz->iparray[GRS_FLAGS][G_PITCH_FLAG],GRS_PITCH,GRS_HPITCH,GRS_PRANGE,dz);
            *transpos = pow(2.0,*transpos);
            if((((int)(gsize_per_chan * *transpos)+1) + iicnt) * 2 >= dz->iparam[SAMPS_IN_INBUF])     /* JUNE 1996 */
                return(0);
            flcnt = (double)iicnt;
            if(!dz->vflag[GRS_NO_INTERP]){
                flcnt_frac = flcnt - (double)iicnt;
                for(n=0;n<gsize_per_chan;n++) {
                    *gbufptr++ = interp_gval(s,flcnt_frac,dz->iparam[GRS_INCHANS]);
                    s++;
                    *gbufptr++ = interp_gval(s,flcnt_frac,dz->iparam[GRS_INCHANS]);
                    flcnt += *transpos;  
                    iicnt = (long)flcnt;
                    s = b + (iicnt * 2);
                    flcnt_frac = flcnt - (double)iicnt;
                }
            } else {            /* do truncate as originally */
                for(n=0;n<gsize_per_chan;n++){
                    *gbufptr++ = *s++;
                    *gbufptr++ = *s;
                    flcnt += *transpos;
                    iicnt = round(flcnt);
                    s = b + (iicnt * 2);
                }   
            }
        }
    }
    *iiptr = s;
    return(1);
}

/***************************** MAKE_MULTICHAN_GRAIN ***************************
 * iicnt = RELATIVE read-pointer in input buffer (starts at 0).
 */

int make_multichan_grain(float *b,float **iiptr,float aamp,int gsize_per_chan,double *transpos,dataptr dz)
{
    long n, k;
    int chans = dz->iparam[GRS_INCHANS];        // GRS_INCHANS = no of chans in input grain, i.e. mono if its been mixed down to mono
    double flcnt;                               //  but = dz->infile->channels, if not
    long iicnt, real_gsize = gsize_per_chan * chans;
    double flcnt_frac;
    float *s = *iiptr, *gbufptr = dz->extrabuf[GRS_GBUF];
    if(aamp>=0) {
        if(!dz->iparray[GRS_FLAGS][G_PITCH_FLAG]) {
            if(real_gsize >= dz->iparam[SAMPS_IN_INBUF])      /* JUNE 1996 */
                return(0);
            for(n=0;n<real_gsize;n++)   /* COPY GRAIN TO GRAINBUF & RE-LEVEL ETC */
                *gbufptr++ = (*s++ * aamp);
        } else {            
            iicnt = (s - b)/chans;
            *transpos = set_dvalue(dz->iparray[GRS_FLAGS][G_PITCH_FLAG],GRS_PITCH,GRS_HPITCH,GRS_PRANGE,dz);
            *transpos = pow(2.0,*transpos);
            if((((int)(gsize_per_chan * *transpos)+1) + iicnt) * chans >= dz->iparam[SAMPS_IN_INBUF])     /* JUNE 1996 */
                return(0);
            flcnt = (double)iicnt;
            if(dz->vflag[GRS_NO_INTERP]){  /* do truncate as originally */
                for(n=0;n<gsize_per_chan;n++){
                    for(k = 0; k < chans;k++) {
                        *gbufptr++ = (*s * aamp);
                        s++;
                    }
                    flcnt += *transpos;
                    iicnt = round(flcnt);
                    s = b + (iicnt * chans);
                }
            } else {            
                flcnt_frac = flcnt - (double)iicnt;
                for(n=0;n<gsize_per_chan;n++) {
                    for(k = 0; k < chans;k++) {
                        *gbufptr++ = interp_gval_with_amp(s,flcnt_frac,dz->iparam[GRS_INCHANS],aamp);
                        s++;
                    }
                    flcnt += *transpos;
                    iicnt = (long)flcnt;
                    s = b + (iicnt * chans);
                    flcnt_frac = flcnt - (double) iicnt;
                }
            }
        }
    } else {        /* NO CHANGE IN AMPLITUDE */
        if(!dz->iparray[GRS_FLAGS][G_PITCH_FLAG]) {
            if(real_gsize >= dz->iparam[SAMPS_IN_INBUF])      /* JUNE 1996 */
                return(0);
            for(n=0;n<real_gsize;n++)
                *gbufptr++ = *s++;
        } else {
            iicnt = (s - b)/chans;
            *transpos = set_dvalue(dz->iparray[GRS_FLAGS][G_PITCH_FLAG],GRS_PITCH,GRS_HPITCH,GRS_PRANGE,dz);
            *transpos = pow(2.0,*transpos);
            if((((int)(gsize_per_chan * *transpos)+1) + iicnt) * chans >= dz->iparam[SAMPS_IN_INBUF])     /* JUNE 1996 */
                return(0);
            flcnt = (double)iicnt;
            if(!dz->vflag[GRS_NO_INTERP]){
                flcnt_frac = flcnt - (double)iicnt;
                for(n=0;n<gsize_per_chan;n++) {
                    for(k=0;k < chans;k++) {
                        *gbufptr++ = interp_gval(s,flcnt_frac,dz->iparam[GRS_INCHANS]);
                        s++;
                    }
                    flcnt += *transpos;
                    iicnt = (long)flcnt;
                    s = b + (iicnt * chans);
                    flcnt_frac = flcnt - (double)iicnt;
                }
            } else {            /* do truncate as originally */
                for(n=0;n<gsize_per_chan;n++){
                    for(k=0;k < chans;k++)
                        *gbufptr++ = *s++;
                    flcnt += *transpos;
                    iicnt = round(flcnt);
                    s = b + (iicnt * chans);
                }   
            }
        }
    }
    *iiptr = s;
    return(1);
}

/************************* WRITE_GRAIN ****************************/

int write_grain(float **maxwrite,float **Fptr, float **FFptr,int gsize_per_chan,int *nctr,dataptr dz)
{
    int exit_status;
    long n, to_doo, exess;
    float *writend;
    long real_gsize = gsize_per_chan * dz->iparam[GRS_INCHANS];
    float *fptr = *Fptr, *ffptr = *FFptr;
    float *gbufptr = dz->extrabuf[GRS_GBUF];
    if((writend = (ffptr + real_gsize)) > *maxwrite)
        *maxwrite = writend;
    if(ffptr + real_gsize > dz->fptr[GRS_LTAILEND]) {
        to_doo = dz->fptr[GRS_LTAILEND] - ffptr;
        if((exess  = real_gsize - to_doo) >= dz->buflen) {
            sprintf(errstr,"Array overflow:write_grain().\n");
            return(PROGRAM_ERROR);
        }
        for(n = 0; n < to_doo; n++)
            *ffptr++ += *gbufptr++;
        if((exit_status = write_samps_granula(dz->buflen,nctr,dz))<0)
            return(exit_status);
        memmove((char *)dz->fptr[GRS_LBUF],(char *)dz->fptr[GRS_LBUFEND],
            (size_t)dz->iparam[GRS_LBUF_SMPXS] * sizeof(float));
        memset((char *)dz->fptr[GRS_LBUFMID],0,dz->iparam[GRS_LONGS_BUFLEN] * sizeof(float));
        ffptr -= dz->iparam[GRS_LONGS_BUFLEN];
        fptr  -= dz->iparam[GRS_LONGS_BUFLEN];
        *maxwrite -= dz->iparam[GRS_LONGS_BUFLEN];  /* APRIL 1996 */
        for(n = 0; n < exess; n++)
            *ffptr++ += *gbufptr++;
        *Fptr  = fptr;
        *FFptr = ffptr;
        return(FINISHED);
    }
    for(n=0;n<real_gsize;n++)
        *ffptr++ += *gbufptr++;
    *Fptr  = fptr;
    *FFptr = ffptr;
    return(FINISHED);
}

/************************* WRITE_STEREO_GRAIN ****************************/

int write_stereo_grain(double rpos,float **maxwrite,float **Fptr,float **FFptr,int gsize_per_chan,int *nctr,dataptr dz)
{
    int exit_status;
    long   n, to_doo, exess;
    long   /**writend,*/ real_gsize = gsize_per_chan * STEREO;
    double lpos;
    double adjust = dehole(rpos);
    float  *writend, *fptr = *Fptr, *ffptr = *FFptr;
    float  *gbufptr = dz->extrabuf[GRS_GBUF];
    lpos  = (1.0 - rpos) * adjust;
    rpos *= adjust;
    if((writend = (ffptr + real_gsize)) > *maxwrite)
        *maxwrite = writend;
    if(ffptr + real_gsize >= dz->fptr[GRS_LTAILEND]) {
        to_doo = dz->fptr[GRS_LTAILEND] - ffptr;
        if((exess  = real_gsize - to_doo) >= dz->iparam[GRS_LONGS_BUFLEN]) {
            sprintf(errstr,"Array overflow: write_stereo_grain()\n");
            return(PROGRAM_ERROR);
        }
        to_doo /= 2;
        for(n = 0; n < to_doo; n++) {
            *ffptr++ += (float) (*gbufptr * lpos);
            *ffptr++ += (float) (*gbufptr++ * rpos);
        }
        if((exit_status = write_samps_granula(dz->iparam[GRS_LONGS_BUFLEN],nctr,dz))<0)
            return(exit_status);
        memmove((char *)dz->fptr[GRS_LBUF],(char *)dz->fptr[GRS_LBUFEND],
            (size_t)dz->iparam[GRS_LBUF_SMPXS] * sizeof(float));
        memset((char *)dz->fptr[GRS_LBUFMID],0,dz->iparam[GRS_LONGS_BUFLEN] * sizeof(float));
        ffptr -= dz->iparam[GRS_LONGS_BUFLEN];
        fptr  -= dz->iparam[GRS_LONGS_BUFLEN];
        *maxwrite -= dz->buflen; /* APR 1996 */
        exess /= 2;
        for(n = 0; n < exess; n++) {
            *ffptr++ += /*round*/(float)(*gbufptr * lpos);
            *ffptr++ += /*round*/(float)(*gbufptr++ * rpos);
        }
        *Fptr  = fptr;
        *FFptr = ffptr;
        return(FINISHED);
    }
    for(n=0;n<gsize_per_chan;n++) {
        *ffptr++ += /*round*/(float)(*gbufptr   * lpos); /*rwd: was *gbuf */
        *ffptr++ += /*round*/(float)(*gbufptr++ * rpos);
    }
    *Fptr  = fptr;
    *FFptr = ffptr;
    return(FINISHED);
}

/****************************** DEHOLE ************************/

#define NONLIN  0.5
#define DEVIATE 0.25

double dehole(double pos)
{
    double comp = 1.0 - (fabs((pos * 2.0) - 1.0));  /* 1 */
    comp = pow(comp,NONLIN);                        /* 2 */
    comp *= DEVIATE;                                /* 3 */
    comp += (1.0 - DEVIATE);                        /* 4 */
    return(comp);
}


/**************************** DO_SCATTER *****************************
 *  scatter forward by fraction of randpart of 1 event separation.
 *
 *        Possible scatter  |       |-------------->|     
 *          Range selected  |       |------>        |   
 *  Random choice within range  |       |--->       |   
 */

long do_scatter(int ostep_per_chan,dataptr dz)
{
    double scat  = dz->param[GRS_SCATTER] * drand48();
    long   smpscat_per_chan = round((double)ostep_per_chan * scat);
    return(smpscat_per_chan);
}               

/******************************** WRITE_SAMPS_GRANULA ****************************
 *
 * Normalise each buffer before writing to obuf, then to file.
 * Save the normalisation factor in array normfact[].
 */

int write_samps_granula(long k,int *nctr,dataptr dz)
{
    int exit_status;
    /*long*/double val = 0.0 /*0L, max_long = 0L*/;
    long n;
    double thisnorm = 1.0, max_double = 0.0;
    float *s = NULL;
    float  *l = dz->fptr[GRS_LBUF];
    switch(dz->process) {
    case(BRASSAGE): s = dz->sampbuf[GRS_OBUF];  break;
    case(SAUSAGE):  s = dz->sampbuf[SAUS_OBUF]; break;
    }
    for(n=0;n<k;n++) {
        if((val = fabs(l[n])) > max_double)
            max_double = val;
    }
    if(/*max_long*/max_double > F_MAXSAMP) {
        thisnorm = (double)F_MAXSAMP/max_double;
        for(n=0;n<k;n++)
            s[n] =  /*round*/(float) ((double)(l[n]) * thisnorm);
    } else {
        for(n=0;n<k;n++)
            s[n] =  l[n];
    }
    if((exit_status = write_samps(s,k,dz))<0)
        return(exit_status);
    (dz->parray[GRS_NORMFACT])[(*nctr)++] = thisnorm;
    if(*nctr >= dz->iparam[GRS_ARRAYSIZE]) {
        dz->iparam[GRS_ARRAYSIZE] += BIGARRAY;
        if((dz->parray[GRS_NORMFACT] = 
        (double *)realloc((char *)(dz->parray[GRS_NORMFACT]),dz->iparam[GRS_ARRAYSIZE]*sizeof(double)))==NULL) {
            sprintf(errstr,"INSUFFICIENT MEMORY to reallocate normalisation array.\n");
            return(MEMORY_ERROR);
        }
    }
    return(FINISHED);
}

#ifndef MULTICHAN

/************************** DO_STEREO_SPLICES *****************************/

void do_stereo_splices(int gsize_per_chan,int bspl,int espl,dataptr dz)
{
    if(dz->iparam[GRS_IS_BTAB] && (dz->iparam[GRS_BSPLICE] < gsize_per_chan/2))
        do_stereo_btab_splice(dz);
    else
        do_stereo_bsplice(gsize_per_chan,dz,bspl);
    if(dz->iparam[GRS_IS_ETAB] && (dz->iparam[GRS_ESPLICE] < gsize_per_chan/2))
        do_stereo_etab_splice(gsize_per_chan,dz);
    else
        do_stereo_esplice(gsize_per_chan,dz,espl);
}

/************************** DO_STEREO_BTAB_SPLICE ****************************/

void do_stereo_btab_splice(dataptr dz)
{
    long n, k = dz->iparam[GRS_BSPLICE];
    double *d;
    float *gbufptr = dz->extrabuf[GRS_GBUF];   
    if(k==0)
        return;
    d = dz->parray[GRS_BSPLICETAB];
    for(n=0;n<k;n++) {
        *gbufptr = (float)/*round*/(*gbufptr * *d); 
        gbufptr++;
        *gbufptr = (float)/*round*/(*gbufptr * *d); 
        gbufptr++;
        d++;
    }
}

/************************** DO_STEREO_BSPLICE ****************************
 *
 * rwd: changed to avoid f/p division, added exponential option
 */
void do_stereo_bsplice(int gsize_per_chan,dataptr dz,int bspl)
{
    double dif,val,lastval,length,newsum,lastsum,twodif;
    long n, k = min(bspl,gsize_per_chan);
    float *gbufptr = dz->extrabuf[GRS_GBUF];
    if(k==0)
        return;
    val = 0.0;
    length = (double)k;
    if(!dz->vflag[GRS_EXPON]){
        dif = 1.0/length;
        lastval = dif;
        *gbufptr++ = (float)val;
        *gbufptr++ = (float)val;
        *gbufptr = (float)/*round*/(*gbufptr * lastval);
        gbufptr++;   
        *gbufptr = (float) /*round*/(*gbufptr * lastval);
        gbufptr++;   
        for(n=2;n<k;n++) {
            val = lastval + dif;
            lastval = val;
            *gbufptr = (float) /*round*/(*gbufptr * val);
            gbufptr++;
            *gbufptr = (float) /*round*/(*gbufptr * val);
            gbufptr++;
        }
    }  else {           /* fast quasi-exponential */
        dif = 1.0/(length*length);
        twodif = dif * 2.0;
        lastsum = 0.0;
        lastval = dif;
        *gbufptr++ = (float)val;/* mca - round or truncate? */
        *gbufptr++ = (float)val;/* mca - round or truncate? */
        *gbufptr = (float) /*round*/(*gbufptr * lastval);    /*** fixed MAY 1998 ***/
        gbufptr++;
        *gbufptr = (float) /*round*/(*gbufptr * lastval);    /*** fixed MAY 1998 ***/
        gbufptr++;
        for(n=2;n<k;n++) {
            newsum = lastsum + twodif;
            val = lastval + newsum + dif;
            *gbufptr = (float) /*round*/(*gbufptr * val);
            gbufptr++;
            *gbufptr = (float) /*round*/(*gbufptr * val);
            gbufptr++;
            lastval = val;
            lastsum = newsum;
        }
    }
}

/************************** DO_STEREO_ETAB_SPLICE ****************************/

void do_stereo_etab_splice(int gsize_per_chan,dataptr dz)
{
    long n, k = dz->iparam[GRS_ESPLICE];
    double *d;
    float *gbufptr = dz->extrabuf[GRS_GBUF] + ((gsize_per_chan - k) * 2);
    if(k==0)
        return;
    d = dz->parray[GRS_ESPLICETAB];
    for(n=0;n<k;n++) {
        *gbufptr = (float) /*round*/(*gbufptr * *d);
        gbufptr++;
        *gbufptr = (float) /*round*/(*gbufptr * *d);
        gbufptr++;
        d++;
    }
}

/************************** DO_STEREO_ESPLICE ****************************/
/* rwd: changed to avoid f/p division, added exponential option */

void do_stereo_esplice(int gsize_per_chan,dataptr dz,int espl)
{
    double dif,val,lastval,length,newsum,lastsum,twodif;
    long n, k = min(espl,gsize_per_chan);
    long real_gsize = gsize_per_chan * 2;
    float *gbufptr = dz->extrabuf[GRS_GBUF] + real_gsize;
    if(k==0)
        return;
    val = 0.0;
    length = (double) k;
    if(!dz->vflag[GRS_EXPON]) {
        dif = 1.0/length;
        lastsum = dif;
        gbufptr--;
        *gbufptr = (float)val;
        gbufptr--;
        *gbufptr = (float)val;
        gbufptr--;
        *gbufptr = (float) /*round*/(*gbufptr * lastsum);
        gbufptr--;
        *gbufptr = (float) /*round*/(*gbufptr * lastsum);
        for(n=k-3;n>=0;n--) {
            val = lastsum + dif;
            lastsum = val;
            gbufptr--;
            *gbufptr = (float) /*round*/(*gbufptr * val);
            gbufptr--;
            *gbufptr = (float) /*round*/(*gbufptr * val);
        }
    } else {            /* fast quasi-exponential */ 
        dif = 1.0/(length * length);
        twodif = dif * 2.0;
        lastsum = 0.0;
        lastval = dif;
        gbufptr--;
        *gbufptr = (float)val;
        gbufptr--;
        *gbufptr = (float)val;
        gbufptr--;
        *gbufptr = (float) /*round*/(*gbufptr * lastval);
        gbufptr--;
        *gbufptr = (float)/*round*/(*gbufptr * lastval);
        for(n=k-3;n>=0;n--) {
            newsum =lastsum + twodif;
            val = lastval + newsum + dif;
            gbufptr--;
            *gbufptr = (float)/*round*/(*gbufptr * val);
            gbufptr--;
            *gbufptr = (float)/*round*/(*gbufptr * val);
            lastval = val;
            lastsum = newsum;
        }
    }
}

#else

/************************** DO_MULTICHAN_SPLICES *****************************/

void do_multichan_splices(int gsize_per_chan,int bspl,int espl,dataptr dz)
{
    if(dz->iparam[GRS_IS_BTAB] && (dz->iparam[GRS_BSPLICE] < gsize_per_chan/2))
        do_multichan_btab_splice(dz);
    else
        do_multichan_bsplice(gsize_per_chan,dz,bspl);
    if(dz->iparam[GRS_IS_ETAB] && (dz->iparam[GRS_ESPLICE] < gsize_per_chan/2))
        do_multichan_etab_splice(gsize_per_chan,dz);
    else
        do_multichan_esplice(gsize_per_chan,dz,espl);
}

/************************** DO_MULTICHAN_BTAB_SPLICE ****************************/

void do_multichan_btab_splice(dataptr dz)
{
    long n, j, k = dz->iparam[GRS_BSPLICE];
    double *d;
    float *gbufptr = dz->extrabuf[GRS_GBUF];
    
    if(k==0)
        return;
    d = dz->parray[GRS_BSPLICETAB];
    for(n=0;n<k;n++) {
        for(j=0;j<dz->iparam[GRS_INCHANS];j++) {
            *gbufptr = (float)/*round*/(*gbufptr * *d);
            gbufptr++;
        }
        d++;
    }
}

/************************** DO_MULTICHAN_BSPLICE ****************************
 *
 * rwd: changed to avoid f/p division, added exponential option
 */
void do_multichan_bsplice(int gsize_per_chan,dataptr dz,int bspl)
{
    double dif,val,lastval,length,newsum,lastsum,twodif;
    long n, j, k = min(bspl,gsize_per_chan);
    float *gbufptr = dz->extrabuf[GRS_GBUF];
    int chans = dz->iparam[GRS_INCHANS];
    if(k==0)
        return;
    val = 0.0;
    length = (double)k;
    if(!dz->vflag[GRS_EXPON]){
        dif = 1.0/length;
        lastval = dif;
        for(j= 0; j<chans;j++)
            *gbufptr++ = (float)val;
        for(j= 0; j<chans;j++) {
            *gbufptr = (float)/*round*/(*gbufptr * lastval);
            gbufptr++;   
        }
        for(n=2;n<k;n++) {
            val = lastval + dif;
            lastval = val;
            for(j= 0; j<chans;j++) {
                *gbufptr = (float) /*round*/(*gbufptr * val);
                gbufptr++;
            }
        }
    }  else {           /* fast quasi-exponential */
        dif = 1.0/(length*length);
        twodif = dif * 2.0;
        lastsum = 0.0;
        lastval = dif;
        for(j=0;j<chans;j++)
            *gbufptr++ = (float)val;/* mca - round or truncate? */
        for(j=0;j<chans;j++) {
            *gbufptr = (float) /*round*/(*gbufptr * lastval);    /*** fixed MAY 1998 ***/
            gbufptr++;
        }
        for(n=2;n<k;n++) {
            newsum = lastsum + twodif;
            val = lastval + newsum + dif;
            for(j=0;j<chans;j++) {
                *gbufptr = (float) /*round*/(*gbufptr * val);
                gbufptr++;
            }
            lastval = val;
            lastsum = newsum;
        }
    }
}

/************************** DO_MULTICHAN_ETAB_SPLICE ****************************/

void do_multichan_etab_splice(int gsize_per_chan,dataptr dz)
{
    long n, j, k = dz->iparam[GRS_ESPLICE];
    double *d;
    int chans = dz->iparam[GRS_INCHANS];
    float *gbufptr = dz->extrabuf[GRS_GBUF] + ((gsize_per_chan - k) * chans);
    if(k==0)
        return;
    d = dz->parray[GRS_ESPLICETAB];
    for(n=0;n<k;n++) {
        for(j=0;j<chans;j++) {
            *gbufptr = (float) /*round*/(*gbufptr * *d); 
            gbufptr++;
        }
        d++;
    }
}

/************************** DO_MULTICHAN_ESPLICE ****************************/
/* rwd: changed to avoid f/p division, added exponential option */

void do_multichan_esplice(int gsize_per_chan,dataptr dz,int espl)
{
    double dif,val,lastval,length,newsum,lastsum,twodif;
    long n, j, k = min(espl,gsize_per_chan);
    int chans = dz->iparam[GRS_INCHANS];
    long real_gsize = gsize_per_chan * chans;
    float *gbufptr = dz->extrabuf[GRS_GBUF] + real_gsize;
    if(k==0)
        return;
    val = 0.0;
    length = (double) k;
    if(!dz->vflag[GRS_EXPON]) {
        dif = 1.0/length;
        lastsum = dif;
        for(j=0;j<chans;j++) {
            gbufptr--;
            *gbufptr = (float)val;
        }
        for(j=0;j<chans;j++) {
            gbufptr--;
            *gbufptr = (float) /*round*/(*gbufptr * lastsum);
        }
        for(n=k-3;n>=0;n--) {
            val = lastsum + dif;
            lastsum = val;
            for(j=0;j<chans;j++) {
                gbufptr--;
                *gbufptr = (float) /*round*/(*gbufptr * val);
            }
        }
    } else {            /* fast quasi-exponential */ 
        dif = 1.0/(length * length);
        twodif = dif * 2.0;
        lastsum = 0.0;
        lastval = dif;
        for(j=0;j<chans;j++) {
            gbufptr--;
            *gbufptr = (float)val;
        }
        for(j=0;j<chans;j++) {
            gbufptr--;
            *gbufptr = (float) /*round*/(*gbufptr * lastval);
        }
        for(n=k-3;n>=0;n--) {
            newsum =lastsum + twodif;
            val = lastval + newsum + dif;
            for(j=0;j<chans;j++) {
                gbufptr--;
                *gbufptr = (float)/*round*/(*gbufptr * val);
            }
            lastval = val;
            lastsum = newsum;
        }
    }
}

#endif

/************************** INTERP_GVAL_WITH_AMP ****************************/

float interp_gval_with_amp(float *s,double flcnt_frac,int chans,float ampp)
{
    /*long*/float tthis = /*(long)*/ *s * ampp;
    /*long*/float next = /*(long)*/ *(s+chans) * ampp;
    //long val  = this + round((double)(next-this) * flcnt_frac);
    //return(short)((val+TWO_POW_14) >> 15);
    return (float) (tthis + ((next-tthis) * flcnt_frac));
}

/************************** INTERP_GVAL ****************************/

float interp_gval(float *s,double flcnt_frac,int chans)
{
    float tthis = *s;
    float next = *(s+chans);
    float val  = (float)(tthis + /*round*/((double)(next-tthis) * flcnt_frac));
    return(val);
}
    
/*************************** SET_RANGE ******************************/

int set_range(int absiicnt,dataptr dz)
{
    long val;
    val = min(dz->iparam[GRS_SRCHRANGE],absiicnt);
    val = round((double)val * drand48());
    return(val);
}

/*************************** SET_OUTSTEP ******************************/

int set_outstep(int gsize_per_chan,dataptr dz)
{
    double dens;
    int val = 0;
    /* TW 4 :2002 */
    switch(dz->process){
    case(BRASSAGE):
        switch(dz->mode) {
        case(GRS_BRASSAGE):
        case(GRS_FULL_MONTY):
        case(GRS_REVERB):
        case(GRS_GRANULATE):
            dens = set_dvalue(dz->iparray[GRS_FLAGS][G_DENSITY_FLAG],GRS_DENSITY,GRS_HDENSITY,GRS_DRANGE,dz);
            val  = round((double)gsize_per_chan/(double)dens);
            break;
        default:
            val  = round((double)gsize_per_chan/(double)GRS_DEFAULT_DENSITY);
        }
        break;

    case(SAUSAGE):
        dens = set_dvalue(dz->iparray[GRS_FLAGS][G_DENSITY_FLAG],GRS_DENSITY,GRS_HDENSITY,GRS_DRANGE,dz);
        val  = round((double)gsize_per_chan/(double)dens);
        break;
    }
    return(val);
}

/*************************** SET_INSTEP ******************************/

int set_instep(int ostep_per_chan,dataptr dz)
{                                               /* rwd: added range error traps */
    double velocity;
    int istep_per_chan = 0;
    switch(dz->process) {        /* TW 4:2002 */
    case(BRASSAGE):
        switch(dz->mode) {
        case(GRS_BRASSAGE):
        case(GRS_FULL_MONTY):
        case(GRS_TIMESTRETCH):
            velocity = set_dvalue(dz->iparray[GRS_FLAGS][G_VELOCITY_FLAG],GRS_VELOCITY,GRS_HVELOCITY,GRS_VRANGE,dz);
            istep_per_chan =  round(velocity * (double)ostep_per_chan);
            break;
        default:
            istep_per_chan =  ostep_per_chan;   /* default velocity is 1.0 */
            break;
        }
        break;
    case(SAUSAGE):
        velocity = set_dvalue(dz->iparray[GRS_FLAGS][G_VELOCITY_FLAG],GRS_VELOCITY,GRS_HVELOCITY,GRS_VRANGE,dz);
        istep_per_chan =  round(velocity * (double)ostep_per_chan);
        break;
    }
    return(istep_per_chan);
}

/*************************** SET_IVALUE ******************************/

int set_ivalue(int flag,int paramno,int hparamno,int rangeno,dataptr dz)
{
    int val = 0;
    switch(flag) {
    case(NOT_SET):
    case(FIXED):
    case(VARIABLE):
        val = dz->iparam[paramno];
        break;
    case(RANGE_VLO):
    case(RANGE_VHI):
    case(RANGE_VHILO):
        dz->iparam[rangeno] = dz->iparam[hparamno] - dz->iparam[paramno];
        /* fall thro */
    case(RANGED):
        val = round((drand48() * dz->iparam[rangeno]) + (double)dz->iparam[paramno]);
        break;
    }    
    return(val);
}

/*************************** SET_DVALUE ******************************/

double set_dvalue(int flag,int paramno,int hparamno,int rangeno,dataptr dz)
{
    double val = 0;
    switch(flag) {
    case(NOT_SET):
    case(FIXED):
    case(VARIABLE):
        val = dz->param[paramno];
        break;
    case(RANGE_VLO):
    case(RANGE_VHI):
    case(RANGE_VHILO):
        dz->param[rangeno] = dz->param[hparamno] - dz->param[paramno];
        /* fall thro */
    case(RANGED):
        val = (drand48() * dz->param[rangeno]) + dz->param[paramno];
        break;
    }    
    return(val);
}

/******************************* READ_SAMPS_SAUSAGE *******************************/

int read_samps_sausage(int firsttime,dataptr dz)
{
    int exit_status, n;
    int samps_read = INT_MAX;   /* i.e. larger than possible */
    for(n=0;n<dz->infilecnt;n++) {
        if(firsttime) {
            if((exit_status = read_a_specific_large_buf(n,dz))<0)
                return(exit_status);
            samps_read = min(samps_read,dz->ssampsread);
        } else {
            if((exit_status = read_a_specific_normal_buf_with_wraparound(n,dz))<0)
                return(exit_status);
            samps_read = min(samps_read,dz->ssampsread);
        }
    }
    if(samps_read==INT_MAX) {           // RWD 06-2019 was LONG_MAX
        sprintf(errstr,"Problem reading sound buffers.\n");
        return(PROGRAM_ERROR);
    }
    if(firsttime)
        dz->iparam[SAMPS_IN_INBUF] = dz->ssampsread;
    else
        dz->iparam[SAMPS_IN_INBUF] = dz->ssampsread + dz->iparam[GRS_BUF_SMPXS];
    return(FINISHED);
}

/*************************** READ_A_SPECIFIC_LARGE_BUF ******************************/

#ifndef MULTICHAN

int read_a_specific_large_buf(int j,dataptr dz)
{
    long bigbufsize = dz->buflen;      /* RWD odd one, this... */
    long n, m, k, samps_read;
    int bufno = SAUS_BUF(j);
    bigbufsize += dz->iparam[GRS_BUF_SMPXS];
    if(dz->iparam[GRS_CHAN_TO_XTRACT]) {
        bigbufsize *= 2;
        if((samps_read = fgetfbufEx(dz->sampbuf[SAUS_SBUF],bigbufsize,dz->ifd[j],0))<0) {
            sprintf(errstr,"Failed to read samps from file %d.\n",j+1);
            return(SYSTEM_ERROR);
        }
        dz->ssampsread = samps_read;
        bigbufsize /= 2;               /* RWD still in samps...buflen + smpxs */
        dz->ssampsread /= 2;
        switch(dz->iparam[GRS_CHAN_TO_XTRACT]) {
        case(1):
            for(n=0,m=0;n<dz->ssampsread;n++,m+=2)
                (dz->sampbuf[bufno])[n] = (dz->sampbuf[SAUS_SBUF])[m];
            break;
        case(2):
            for(n=0,m=1;n<dz->ssampsread;n++,m+=2)
                (dz->sampbuf[bufno])[n] = (dz->sampbuf[SAUS_SBUF])[m];
            break;
        case(BOTH_CHANNELS):
            for(n=0,m=0,k=1;n<dz->ssampsread;n++,m+=2,k+=2)
                (dz->sampbuf[bufno])[n] = (float)(((dz->sampbuf[SAUS_SBUF])[m] + (dz->sampbuf[SAUS_SBUF])[k])* 0.5f);
            break;
        }
    } else {
        if((samps_read = fgetfbufEx(dz->sampbuf[bufno],bigbufsize,dz->ifd[j],0))<0) {
            sprintf(errstr,"Failed to read samps from file %d.\n",j+1);
            return(SYSTEM_ERROR);
        }
        dz->ssampsread = samps_read;
    }
    /* dz->bigbufsize -= dz->iparam[GRS_BUF_XS]; */ /* leaves dz->buflen unchanged, which is fine */
    return(FINISHED);
}

#else

int read_a_specific_large_buf(int j,dataptr dz)
{
    long bigbufsize = dz->buflen;      /* RWD odd one, this... */
    long n, m, samps_read, ibufcnt;
    int bufno = SAUS_BUF(j), chans = dz->infile->channels;
    double sum;
    bigbufsize += dz->iparam[GRS_BUF_SMPXS];
    if(dz->iparam[GRS_CHAN_TO_XTRACT]) {
        bigbufsize *= chans;
        if((samps_read = fgetfbufEx(dz->sampbuf[SAUS_SBUF],bigbufsize,dz->ifd[j],0))<0) {
            sprintf(errstr,"Failed to read samps from file %d.\n",j+1);
            return(SYSTEM_ERROR);
        }
        dz->ssampsread = samps_read;
        bigbufsize /= chans;               /* RWD still in samps...buflen + smpxs */
        dz->ssampsread /= chans;
        switch(dz->iparam[GRS_CHAN_TO_XTRACT]) {
        case(ALL_CHANNELS):
            ibufcnt = 0;
            for(n=0;n<dz->ssampsread;n++) {
                sum = 0.0;
                for(m=0;m<chans;m++)
                    sum += dz->sampbuf[GRS_SBUF][ibufcnt++];
                dz->sampbuf[bufno][n] = (float)(sum/(double)chans);
            }
            break;
        default:
            for(n=0,m=dz->iparam[GRS_CHAN_TO_XTRACT];n<dz->ssampsread;n++,m+=chans)
                dz->sampbuf[bufno][n] = dz->sampbuf[GRS_SBUF][m];
            break;
        }
    } else {
        if((samps_read = fgetfbufEx(dz->sampbuf[bufno],bigbufsize,dz->ifd[j],0))<0) {
            sprintf(errstr,"Failed to read samps from file %d.\n",j+1);
            return(SYSTEM_ERROR);
        }
        dz->ssampsread = samps_read;
    }
    return(FINISHED);
}

#endif

/*************************** READ_A_SPECIFIC_NORMAL_BUF_WITH_WRAPAROUND ******************************/

#ifndef MULTICHAN

int read_a_specific_normal_buf_with_wraparound(int j,dataptr dz)
{
    long bigbufsize = dz->buflen;
    long n,m,k,samps_read;
    int bufno  = SAUS_BUF(j);
    int ibufno = SAUS_IBUF(j);
    memmove((char *)dz->sampbuf[bufno],(char *)(dz->sbufptr[bufno]),
        dz->iparam[GRS_BUF_SMPXS] * sizeof(float));
    if(dz->iparam[GRS_CHAN_TO_XTRACT]) {
        bigbufsize *= 2;
        if((samps_read = fgetfbufEx(dz->sampbuf[SAUS_SBUF],bigbufsize,dz->ifd[j],0))<0) {
            sprintf(errstr,"Failed to read from file %d.\n",j+1);
            return(SYSTEM_ERROR);
        }
        dz->ssampsread = samps_read;
        bigbufsize /= 2;
        dz->ssampsread /= 2;
        switch(dz->iparam[GRS_CHAN_TO_XTRACT]) {
        case(1):
            for(n=0,m=0;n<dz->ssampsread;n++,m+=2)
                (dz->sampbuf[ibufno])[n] = (dz->sampbuf[GRS_SBUF])[m];
            break;
        case(2):
            for(n=0,m=1;n<dz->ssampsread;n++,m+=2)
                (dz->sampbuf[ibufno])[n] = (dz->sampbuf[GRS_SBUF])[m];
            break;
        case(BOTH_CHANNELS):
            for(n=0,m=0,k=1;n<dz->ssampsread;n++,m+=2,k+=2)
                (dz->sampbuf[ibufno])[n] = (float)(((dz->sampbuf[GRS_SBUF])[m] + (dz->sampbuf[GRS_SBUF])[k])* 0.5f);
            break;
        }
    } else {
        if((samps_read = fgetfbufEx(dz->sampbuf[ibufno],bigbufsize,dz->ifd[j],0))<0) {
            sprintf(errstr,"Failed to read from file %d.\n",j+1);
            return(SYSTEM_ERROR);
        }
        dz->ssampsread = samps_read;
    }
    return(FINISHED);
}

#else

int read_a_specific_normal_buf_with_wraparound(int j,dataptr dz)
{
    long bigbufsize = dz->buflen;
    long n,m,samps_read, ibufcnt;
    double sum;
    int bufno  = SAUS_BUF(j);
    int ibufno = SAUS_IBUF(j), chans = dz->infile->channels;
    memmove((char *)dz->sampbuf[bufno],(char *)(dz->sbufptr[bufno]),dz->iparam[GRS_BUF_SMPXS] * sizeof(float));
    if(dz->iparam[GRS_CHAN_TO_XTRACT]) {
        bigbufsize *= chans;
        if((samps_read = fgetfbufEx(dz->sampbuf[SAUS_SBUF],bigbufsize,dz->ifd[j],0))<0) {
            sprintf(errstr,"Failed to read from file %d.\n",j+1);
            return(SYSTEM_ERROR);
        }
        dz->ssampsread = samps_read;
        bigbufsize /= chans;
        dz->ssampsread /= chans;
        switch(dz->iparam[GRS_CHAN_TO_XTRACT]) {
        case(ALL_CHANNELS):
            ibufcnt = 0;
            for(n=0;n<dz->ssampsread;n++) {
                sum = 0.0;
                for(m=0;m<chans;m++)
                    sum += dz->sampbuf[GRS_SBUF][ibufcnt++];
                dz->sampbuf[ibufno][n] = (float)(sum/(double)chans);
            }
            break;
        default:
            for(n=0,m=dz->iparam[GRS_CHAN_TO_XTRACT];n<dz->ssampsread;n++,m+=chans)
                dz->sampbuf[ibufno][n] = dz->sampbuf[GRS_SBUF][m];
            break;
        }
    } else {
        if((samps_read = fgetfbufEx(dz->sampbuf[ibufno],bigbufsize,dz->ifd[j],0))<0) {
            sprintf(errstr,"Failed to read from file %d.\n",j+1);
            return(SYSTEM_ERROR);
        }
        dz->ssampsread = samps_read;
    }
    return(FINISHED);
}

#endif

/*************************** BAKTRAK_SAUSAGE ******************************
 *
 *     <------------ baktrak(b) ---------------->
 *
 *     <--(b-x)-->
 *                <------------ x -------------->
 *               |-------- current bufer --------|
 *
 *     |-------- new buffer --------|
 *      <------------x------------->
 *              
 */

#ifndef MULTICHAN

int baktrak_sausage(int thissnd,long samptotal,int absiicnt_per_chan,float **iiptr,dataptr dz)
{
    int  exit_status;
    long bktrk, new_position;
    unsigned long reset_size = dz->buflen + dz->iparam[GRS_BUF_SMPXS];
//TW I agree, this is FINE!!, and, with sndseekEx, algo is more efficient
//  whenever the search-range is relatively small (and equally efficient otherwise)
    bktrk = samptotal - (absiicnt_per_chan * dz->iparam[GRS_INCHANS]);
    *iiptr      = dz->sampbuf[SAUS_BUF(thissnd)];

    if((new_position = samptotal - bktrk)<0) {
        fprintf(stdout,"WARNING: Non-fatal program error:\nRange arithmetic problem - 2, in baktraking.\n");
        fflush(stdout);
        new_position = 0;
        *iiptr = dz->sampbuf[SAUS_BUF(thissnd)];
    }
    if(dz->iparam[GRS_CHAN_TO_XTRACT])   /* IF we've converted from STEREO file */
        new_position *= 2;
    if(sndseekEx(dz->ifd[thissnd],new_position,0)<0) {
        sprintf(errstr,"sndseek error: baktrak_sausage()\n");
        return(SYSTEM_ERROR);
    }
    memset((char *)dz->sampbuf[SAUS_BUF(thissnd)],0,reset_size * sizeof(float));
    if(dz->iparam[GRS_CHAN_TO_XTRACT]) {
        reset_size *= 2;
        memset((char *)dz->sampbuf[SAUS_SBUF],0,reset_size * sizeof(float));
    }
    if((exit_status = read_a_specific_large_buf(thissnd,dz))<0)
        return(exit_status);
    dz->iparam[SAMPS_IN_INBUF] = dz->ssampsread;
    return(FINISHED);
}

#else

int baktrak_sausage(int thissnd,long samptotal,int absiicnt_per_chan,float **iiptr,dataptr dz)
{
    int  exit_status,  chans = dz->infile->channels;
    long bktrk, new_position;
    unsigned long reset_size = dz->buflen + dz->iparam[GRS_BUF_SMPXS];
    bktrk = samptotal - (absiicnt_per_chan * dz->iparam[GRS_INCHANS]);
    *iiptr      = dz->sampbuf[SAUS_BUF(thissnd)];

    if((new_position = samptotal - bktrk)<0) {
        fprintf(stdout,"WARNING: Non-fatal program error:\nRange arithmetic problem - 2, in baktraking.\n");
        fflush(stdout);
        new_position = 0;
        *iiptr = dz->sampbuf[SAUS_BUF(thissnd)];
    }
    if(dz->iparam[GRS_CHAN_TO_XTRACT])   /* IF we've converted from MULTICHAN file */
        new_position *= chans;
    if(sndseekEx(dz->ifd[thissnd],new_position,0)<0) {
        sprintf(errstr,"sndseek error: baktrak_sausage()\n");
        return(SYSTEM_ERROR);
    }
    memset((char *)dz->sampbuf[SAUS_BUF(thissnd)],0,reset_size * sizeof(float));
    if(dz->iparam[GRS_CHAN_TO_XTRACT]) {
        reset_size *= chans;
        memset((char *)dz->sampbuf[SAUS_SBUF],0,reset_size * sizeof(float));
    }
    if((exit_status = read_a_specific_large_buf(thissnd,dz))<0)
        return(exit_status);
    dz->iparam[SAMPS_IN_INBUF] = dz->ssampsread;
    return(FINISHED);
}

#endif

/****************************** RESET_SAUSAGE *******************************/

#ifndef MULTICHAN

int reset_sausage(int thissnd,int resetskip,dataptr dz)
{
    int exit_status;
    unsigned long reset_size = dz->buflen + dz->iparam[GRS_BUF_SMPXS];

    memset((char *)dz->sampbuf[SAUS_BUF(thissnd)],0,reset_size * sizeof(float));
    if(dz->iparam[GRS_CHAN_TO_XTRACT]) {
        reset_size *= 2;
        memset((char *)dz->sampbuf[SAUS_SBUF],0,reset_size * sizeof(float));
    }
    if(dz->iparam[GRS_CHAN_TO_XTRACT]) /* If we've converted from a stereo file */
        resetskip *= 2;
    if(sndseekEx(dz->ifd[thissnd],resetskip,0)<0) {
        sprintf(errstr,"sndseek error: reset_sausage()\n");
        return(SYSTEM_ERROR);
    }
    if((exit_status = read_a_specific_large_buf(thissnd,dz))<0)
        return(exit_status);
    dz->iparam[SAMPS_IN_INBUF] = dz->ssampsread;  
    return(FINISHED);
}

#else

int reset_sausage(int thissnd,int resetskip,dataptr dz)
{
    int exit_status, chans = dz->infile->channels;
    unsigned long reset_size = dz->buflen + dz->iparam[GRS_BUF_SMPXS];

    memset((char *)dz->sampbuf[SAUS_BUF(thissnd)],0,reset_size * sizeof(float));
    if(dz->iparam[GRS_CHAN_TO_XTRACT]) {
        reset_size *= chans;
        memset((char *)dz->sampbuf[SAUS_SBUF],0,reset_size * sizeof(float));
    }
    if(dz->iparam[GRS_CHAN_TO_XTRACT]) /* If we've converted from a stereo file */
        resetskip *= chans;
    if(sndseekEx(dz->ifd[thissnd],resetskip,0)<0) {
        sprintf(errstr,"sndseek error: reset_sausage()\n");
        return(SYSTEM_ERROR);
    }
    if((exit_status = read_a_specific_large_buf(thissnd,dz))<0)
        return(exit_status);
    dz->iparam[SAMPS_IN_INBUF] = dz->ssampsread;  
    return(FINISHED);
}

#endif

/****************************** GET_NEXT_INSND *******************************/

int get_next_insnd(dataptr dz)
{
    if(dz->itemcnt <= 0) {
        perm_sausage(dz->infilecnt,dz);
        dz->itemcnt = dz->infilecnt;
    }
    dz->itemcnt--;
    return(dz->iparray[SAUS_PERM][dz->itemcnt]);
}

/****************************** PERM_SAUSAGE *******************************/

void perm_sausage(int cnt,dataptr dz)
{
    int n, t;
    for(n=0;n<cnt;n++) {
        t = (int)(drand48() * (double)(n+1));    /* TRUNCATE */
        if(t==n)
            prefix(n,cnt-1,dz);
        else
            insert(n,t,cnt-1,dz);
    }
}

/****************************** INSERT ****************************/

void insert(int n,int t,int cnt_less_one,dataptr dz)
{   
    shuflup(t+1,cnt_less_one,dz);
    dz->iparray[SAUS_PERM][t+1] = n;
}

/****************************** PREFIX ****************************/

void prefix(int n,int cnt_less_one,dataptr dz)
{   
    shuflup(0,cnt_less_one,dz);
    dz->iparray[SAUS_PERM][0] = n;
}

/****************************** SHUFLUP ****************************/

void shuflup(int k,int cnt_less_one,dataptr dz)
{   
    int n;
    for(n = cnt_less_one; n > k; n--)
        dz->iparray[SAUS_PERM][n] = dz->iparray[SAUS_PERM][n-1];
}

/****************************** SAUSAGE_PREPROCESS ****************************/

int sausage_preprocess(dataptr dz)
{
    if((dz->iparray[SAUS_PERM] = (int *)malloc(dz->infilecnt * sizeof(int)))==NULL) {
        sprintf(errstr,"INSUFFICIENT MEMORY for permutation array for sausage.\n");
        return(MEMORY_ERROR);
    }
    dz->iparray[SAUS_PERM][0] = dz->infilecnt + 1;  /* impossible value to initialise perm */

    return create_sized_outfile(dz->outfilename,dz);
    /*return(FINISHED);*/
}

/*************************** CREATE_SAUSAGE_BUFFERS **************************/

#ifndef MULTICHAN

int create_sausage_buffers(dataptr dz)
{   
    long standard_block = (long)Malloc(-1);
    long this_bloksize;
    int   exit_status, n;
    int   convert_to_stereo = FALSE, overall_size, bufdivisor = 0;
    float *tailend;
    long  stereo_buflen = 0, stereo_bufxs = 0, outbuflen;
//TW All buffers are in floats, so this not needed
//  int   lfactor = sizeof(long)/sizeof(float), n;
    if(dz->iparray[GRS_FLAGS][G_SPACE_FLAG])
        convert_to_stereo = TRUE;                           
    if((dz->extrabuf[GRS_GBUF] = (float *)malloc(dz->iparam[GRS_GLBUF_SMPXS] * sizeof(float)))==NULL) {
        sprintf(errstr,"INSUFFICIENT MEMORY to create grain buffer.\n");     /* GRAIN BUFFER */
        return(MEMORY_ERROR);
    }
                /* CALCULATE NUMBER OF BUFFER CHUNKS REQUIRED : bufdivisor */

    if(dz->iparam[GRS_CHANNELS]>0)
        bufdivisor += 2;                            /* 2 for stereo-infile, before reducing to mono */
//TW All buffers are in floats
//  bufdivisor += dz->infilecnt + 1 + lfactor;      /* infilecnt IN mono, 1 OUT,   1 long OUT  */
    bufdivisor += dz->infilecnt + 2;                /* infilecnt IN mono, 1 OUT,   1 LBUF OUT  */
    if(convert_to_stereo)
//TW All buffers are in floats
//      bufdivisor += 1 + lfactor;                  /*                    2nd OUT, 2nd long OUT */
        bufdivisor += 2;                            /*                    2nd OUT, 2nd LBUF OUT */

    this_bloksize = standard_block;
    for(;;) {
        if((exit_status = grab_an_appropriate_block_of_sausage_memory(&this_bloksize,standard_block,bufdivisor,dz))<0)
            return(exit_status);

                    /* CALCULATE AND ALLOCATE TOTAL MEMORY REQUIRED : overall_size */
    
        overall_size = (dz->buflen * bufdivisor) + (dz->iparam[GRS_BUF_SMPXS] * dz->infilecnt) + dz->iparam[GRS_LBUF_SMPXS];
        if(dz->iparam[GRS_CHANNELS])                
            overall_size += 2 * dz->iparam[GRS_BUF_SMPXS];                  /* IF stereo, also allow for bufxs in stereo inbuf */

//TW    if(overall_size<0) 
        if(overall_size * sizeof(float)<0) {
            sprintf(errstr,"INSUFFICIENT MEMORY for sound buffers.\n"); /* arithmetic overflow */
            return(MEMORY_ERROR);
        }
        if((dz->bigbuf=(float *)malloc(overall_size * sizeof(float)))==NULL) {
            sprintf(errstr,"INSUFFICIENT MEMORY to create sound buffers.\n");
            return(MEMORY_ERROR);
        }
                    /* SET SIZE OF inbuf, outbuf, AND Lbuf (FOR CALCS) */
        outbuflen   = dz->buflen;
        if(convert_to_stereo)                               /* For stereo out, outbuflen is double length of inbuf */
            outbuflen *= 2;
        if(dz->iparam[GRS_CHANNELS]) {
            stereo_buflen = dz->buflen * 2;
            stereo_bufxs  = dz->iparam[GRS_BUF_SMPXS] * 2;
        }                                        
        dz->iparam[GRS_LONGS_BUFLEN] = outbuflen;           /* Longs buffer is same size as obuf */
        if(dz->iparam[GRS_LBUF_SMPXS] > dz->iparam[GRS_LONGS_BUFLEN])
            continue;
        break;
    }
                /* DIVIDE UP ALLOCATED MEMORY IN SPECIALISED BUFFERS */
    if(dz->iparam[GRS_CHANNELS]) {                                  /* sbuf : extra stereo input buffer, if required */
        dz->sampbuf[SAUS_SBUF]   = dz->bigbuf;
        dz->sampbuf[SAUS_BUF(0)] = dz->sampbuf[SAUS_SBUF] + stereo_buflen + stereo_bufxs;
    } else
        dz->sampbuf[SAUS_BUF(0)] = dz->bigbuf;
    dz->sbufptr[SAUS_BUF(0)]  = dz->sampbuf[SAUS_BUF(0)] + dz->buflen;
    dz->sampbuf[SAUS_IBUF(0)] = dz->sampbuf[SAUS_BUF(0)] + dz->iparam[GRS_BUF_SMPXS];
    tailend                   = dz->sbufptr[SAUS_BUF(0)] + dz->iparam[GRS_BUF_SMPXS];
    for(n=1;n<dz->infilecnt;n++) {
        dz->sampbuf[SAUS_BUF(n)]  = tailend;                                   /* Lbuf: buffer for calculations */
        dz->sbufptr[SAUS_BUF(n)]  = dz->sampbuf[SAUS_BUF(n)] + dz->buflen;  
        dz->sampbuf[SAUS_IBUF(n)] = dz->sampbuf[SAUS_BUF(n)] + dz->iparam[GRS_BUF_SMPXS];
        tailend                   = dz->sbufptr[SAUS_BUF(n)] + dz->iparam[GRS_BUF_SMPXS];
    }
    dz->fptr[GRS_LBUF]     = tailend;
    dz->fptr[GRS_LBUFEND]  = dz->fptr[GRS_LBUF] + dz->iparam[GRS_LONGS_BUFLEN];
    dz->fptr[GRS_LTAILEND] = dz->fptr[GRS_LBUFEND] + dz->iparam[GRS_LBUF_SMPXS];
    dz->fptr[GRS_LBUFMID]  = dz->fptr[GRS_LBUF]    + dz->iparam[GRS_LBUF_SMPXS];
    dz->sampbuf[SAUS_OBUF]  = /*(short *)*/(dz->fptr[GRS_LTAILEND]);

                                /* INITIALISE BUFFERS */

    memset((char *)dz->bigbuf,0,overall_size * sizeof(float));
    return(FINISHED);
}

#else

int create_sausage_buffers(dataptr dz)
{
    long standard_block = (long)Malloc(-1);
    long this_bloksize;
    int   exit_status, n, chans = dz->infile->channels;
    int   overall_size, bufdivisor = 0;
    float *tailend;
    long  multichan_buflen = 0, multichan_bufxs = 0, outbuflen;
    if((dz->extrabuf[GRS_GBUF] = (float *)malloc(dz->iparam[GRS_GLBUF_SMPXS] * sizeof(float)))==NULL) {
        sprintf(errstr,"INSUFFICIENT MEMORY to create grain buffer.\n");     /* GRAIN BUFFER */
        return(MEMORY_ERROR);
    }
                /* CALCULATE NUMBER OF BUFFER CHUNKS REQUIRED : bufdivisor */

    if(dz->iparam[GRS_CHANNELS]>0)
        bufdivisor += chans;                            /* chans for multichan-infile, before reducing to mono */
    bufdivisor += dz->infilecnt;                        /* infilecnt IN mono, 1 OUT,   1 LBUF OUT  */
    for(n=0;n<dz->outfile->channels;n++)
        bufdivisor += 1 + sizeof(long)/sizeof(float);   /* 1 float and 1 long buf for each input channel */
    this_bloksize = standard_block;
    for(;;) {
        if((exit_status = grab_an_appropriate_block_of_sausage_memory(&this_bloksize,standard_block,bufdivisor,dz))<0)
            return(exit_status);

                    /* CALCULATE AND ALLOCATE TOTAL MEMORY REQUIRED : overall_size */
    
        overall_size = (dz->buflen * bufdivisor) + (dz->iparam[GRS_BUF_SMPXS] * dz->infilecnt) + dz->iparam[GRS_LBUF_SMPXS];
        if(dz->iparam[GRS_CHANNELS])                
            overall_size += chans * dz->iparam[GRS_BUF_SMPXS];                  /* IF multichan, also allow for bufxs in multichan inbuf */

        if(overall_size * sizeof(float)<0) {
            sprintf(errstr,"INSUFFICIENT MEMORY for sound buffers.\n"); /* arithmetic overflow */
            return(MEMORY_ERROR);
        }
        if((dz->bigbuf=(float *)malloc(overall_size * sizeof(float)))==NULL) {
            sprintf(errstr,"INSUFFICIENT MEMORY to create sound buffers.\n");
            return(MEMORY_ERROR);
        }
                    /* SET SIZE OF inbuf, outbuf, AND Lbuf (FOR CALCS) */
        outbuflen = dz->buflen;

        outbuflen *= dz->out_chans;
        if(dz->iparam[GRS_CHANNELS]) {
            multichan_buflen = dz->buflen * chans;
            multichan_bufxs  = dz->iparam[GRS_BUF_SMPXS] * chans;
        }
        dz->iparam[GRS_LONGS_BUFLEN] = outbuflen;           /* Longs buffer is same size as obuf */
        if(dz->iparam[GRS_LBUF_SMPXS] > dz->iparam[GRS_LONGS_BUFLEN])
            continue;
        break;
    }
                /* DIVIDE UP ALLOCATED MEMORY IN SPECIALISED BUFFERS */
    if(dz->iparam[GRS_CHANNELS]) {                                  /* sbuf : extra stereo input buffer, if required */
        dz->sampbuf[SAUS_SBUF]   = dz->bigbuf;
        dz->sampbuf[SAUS_BUF(0)] = dz->sampbuf[SAUS_SBUF] + multichan_buflen + multichan_bufxs;
    } else
        dz->sampbuf[SAUS_BUF(0)] = dz->bigbuf;
    dz->sbufptr[SAUS_BUF(0)]  = dz->sampbuf[SAUS_BUF(0)] + dz->buflen;
    dz->sampbuf[SAUS_IBUF(0)] = dz->sampbuf[SAUS_BUF(0)] + dz->iparam[GRS_BUF_SMPXS];
    tailend                   = dz->sbufptr[SAUS_BUF(0)] + dz->iparam[GRS_BUF_SMPXS];
    for(n=1;n<dz->infilecnt;n++) {
        dz->sampbuf[SAUS_BUF(n)]  = tailend;                                   /* Lbuf: buffer for calculations */
        dz->sbufptr[SAUS_BUF(n)]  = dz->sampbuf[SAUS_BUF(n)] + dz->buflen;
        dz->sampbuf[SAUS_IBUF(n)] = dz->sampbuf[SAUS_BUF(n)] + dz->iparam[GRS_BUF_SMPXS];
        tailend                   = dz->sbufptr[SAUS_BUF(n)] + dz->iparam[GRS_BUF_SMPXS];
    }
    dz->fptr[GRS_LBUF]     = tailend;
    dz->fptr[GRS_LBUFEND]  = dz->fptr[GRS_LBUF] + dz->iparam[GRS_LONGS_BUFLEN];
    dz->fptr[GRS_LTAILEND] = dz->fptr[GRS_LBUFEND] + dz->iparam[GRS_LBUF_SMPXS];
    dz->fptr[GRS_LBUFMID]  = dz->fptr[GRS_LBUF]    + dz->iparam[GRS_LBUF_SMPXS];
    dz->sampbuf[SAUS_OBUF]  = /*(short *)*/(dz->fptr[GRS_LTAILEND]);

                                /* INITIALISE BUFFERS */

    memset((char *)dz->bigbuf,0,overall_size * sizeof(float));
    return(FINISHED);
}

#endif

/*  INPUT BUFFERS :-
 *
 *  |-----------BUFLEN-----------|
 *
 *  buf      ibuf          bufend    tailend
 *  |_________|__________________|buf_smpxs|  ..... (obuf->)
 *                               /
 *  |buf_smpxs|           <<-COPY_________/
 *
 *            |-----------BUFLEN-----------|
 *
 *
 *
 *  OUTPUT LONGS BUFFER:-
 *
 *  Lbuf       Lbufmid    Lbufend
 *  |____________|_______________|_Lbuf_smpxs_|
 *                               /
 *  |_Lbuf_smpxs_|         <<-COPY___________/
 *
 */

/*************************** GRAB_AN_APPROPRIATE_BLOCK_OF_SAUSAGE_MEMORY **************************/

#ifndef MULTICHAN

int grab_an_appropriate_block_of_sausage_memory(long *this_bloksize,long standard_block,int bufdivisor,dataptr dz)
{
    /*int  sector_blok;*/
    do {
//TW    if((dz->buflen = *this_bloksize)< 0) {  /* arithmetic overflow */
        if((dz->buflen = *this_bloksize) * sizeof(float) < 0) { /* arithmetic overflow */
            sprintf(errstr,"INSUFFICIENT MEMORY for sound buffers.\n");
            return(MEMORY_ERROR);
        }
        *this_bloksize += standard_block;
                /* CALCULATE SIZE OF BUFFER REQUIRED : dz->bigbufsize */

        dz->buflen -= (dz->infilecnt * dz->iparam[GRS_BUF_SMPXS]) + dz->iparam[GRS_LBUF_SMPXS]; 
                                                            /* Allow for overflow areas */
        if(dz->iparam[GRS_CHANNELS])                
            dz->buflen -= 2 * dz->iparam[GRS_BUF_SMPXS];    /* Allow for overflow space in additional stereo inbuf */
        dz->buflen /= bufdivisor;                       /* get unit buffersize */
    /*  sector_blok = SECSIZE;  */                          /* Read and write buf sizes must be multiples of SECSIZE */
        if(dz->iparam[GRS_CHANNELS])                        /* If reading stereo: 2* SECSIZE reduces to single mono SECSIZE */
    /*      sector_blok *= 2;       */                      /* So dz->bigbufsize must be a multiple of (2 * SECSIZE) */
            dz->buflen = (dz->buflen / STEREO) * STEREO;       /*RWD: */
    
    /*  dz->buflen = (dz->bigbufsize/sector_blok) * sector_blok;*/
    } while(dz->buflen <= 0);
    return(FINISHED);
}

#else

int grab_an_appropriate_block_of_sausage_memory(long *this_bloksize,long standard_block,int bufdivisor,dataptr dz)
{
    do {
        if((dz->buflen = *this_bloksize) * sizeof(float) < 0) { /* arithmetic overflow */
            sprintf(errstr,"INSUFFICIENT MEMORY for sound buffers.\n");
            return(MEMORY_ERROR);
        }
        *this_bloksize += standard_block;
        dz->buflen -= (dz->infilecnt * dz->iparam[GRS_BUF_SMPXS]) + dz->iparam[GRS_LBUF_SMPXS]; 
                                                            /* Allow for overflow areas */
        if(dz->iparam[GRS_CHANNELS])                
            dz->buflen -= dz->infile->channels * dz->iparam[GRS_BUF_SMPXS]; /* Allow for overflow space in additional multichan inbuf */
        dz->buflen /= bufdivisor;                           /* get unit buffersize */
        if(dz->iparam[GRS_CHANNELS])                        /* If reading multichano: chans * SECSIZE reduces to single mono SECSIZE */
            dz->buflen = (dz->buflen / dz->infile->channels) * dz->infile->channels;
    } while(dz->buflen <= 0);
    return(FINISHED);
}

#endif


#ifdef MULTICHAN

/************************* WRITE_MULTICHAN_GRAIN ****************************/

int write_multichan_grain(double rpos,int chana,int chanb,float **maxwrite,float **Fptr,float **FFptr,int gsize_per_chan,int *nctr,dataptr dz)
{
    int exit_status;
    long   n, to_doo, exess;
    long   real_gsize = gsize_per_chan * dz->out_chans;
    double lpos;
    double adjust = dehole(rpos);
    float  *writend, *fptr = *Fptr, *ffptr = *FFptr;
    float  *gbufptr = dz->extrabuf[GRS_GBUF];
    lpos  = (1.0 - rpos) * adjust;
    rpos *= adjust;
    chana--;
    chanb--;
    if((writend = (ffptr + real_gsize)) > *maxwrite)
        *maxwrite = writend;
    if(ffptr + real_gsize >= dz->fptr[GRS_LTAILEND]) {
        to_doo = dz->fptr[GRS_LTAILEND] - ffptr;
        if((exess  = real_gsize - to_doo) >= dz->iparam[GRS_LONGS_BUFLEN]) {
            sprintf(errstr,"Array overflow: write_stereo_grain()\n");
            return(PROGRAM_ERROR);
        }
        to_doo /= dz->out_chans;
        for(n = 0; n < to_doo; n++) {
            *(ffptr + chana) += (float) (*gbufptr * lpos);
            *(ffptr + chanb) += (float) (*gbufptr * rpos);
            gbufptr++;
            ffptr += dz->out_chans;
        }
        if((exit_status = write_samps_granula(dz->iparam[GRS_LONGS_BUFLEN],nctr,dz))<0)
            return(exit_status);
        memmove((char *)dz->fptr[GRS_LBUF],(char *)dz->fptr[GRS_LBUFEND],
            (size_t)dz->iparam[GRS_LBUF_SMPXS] * sizeof(float));
        memset((char *)dz->fptr[GRS_LBUFMID],0,dz->iparam[GRS_LONGS_BUFLEN] * sizeof(float));
        ffptr -= dz->iparam[GRS_LONGS_BUFLEN];
        fptr  -= dz->iparam[GRS_LONGS_BUFLEN];
        *maxwrite -= dz->buflen; /* APR 1996 */
        exess /= dz->out_chans;
        for(n = 0; n < exess; n++) {
            *(ffptr + chana) += (float) (*gbufptr * lpos);
            *(ffptr + chanb) += (float) (*gbufptr * rpos);
            gbufptr++;
            ffptr += dz->out_chans;
        }
        *Fptr  = fptr;
        *FFptr = ffptr;
        return(FINISHED);
    }
    for(n=0;n<gsize_per_chan;n++) {
        *(ffptr + chana) += (float) (*gbufptr * lpos);
        *(ffptr + chanb) += (float) (*gbufptr * rpos);
        gbufptr++;
        ffptr += dz->out_chans;
    }
    *Fptr  = fptr;
    *FFptr = ffptr;
    return(FINISHED);
}

#endif