pvcompand~.c

/* FFTease for Pd */

#include "fftease.h"

static t_class *pvcompand_class;

#define OBJECT_NAME "pvcompand~"

typedef struct _pvcompand
{
    t_object x_obj;
    t_float x_f;
    t_fftease *fft;
    t_float rescale;
    t_float *curthresh;
    t_float *atten;
    t_float *thresh;
    int count;
    t_float thresh_interval;
    t_float max_atten;
    t_float atten_interval;
    t_float tstep;
    t_float gstep;
    t_float last_max_atten;
    short norml;
    short mute;
} t_pvcompand;

static void pvcompand_dsp(t_pvcompand *x, t_signal **sp);
static t_int *pvcompand_perform(t_int *w);
static void *pvcompand_new(t_symbol *s, int argc, t_atom *argv);
static void update_thresholds(t_pvcompand *x);
static void pvcompand_normalize(t_pvcompand *x, t_floatarg val);
static void pvcompand_free(t_pvcompand *x);
static t_float pvcompand_ampdb(t_float db);
static void pvcompand_init(t_pvcompand *x);
static void pvcompand_mute(t_pvcompand *x, t_floatarg f);

void pvcompand_tilde_setup(void)
{
    t_class *c;
    c = class_new(gensym("pvcompand~"), (t_newmethod)pvcompand_new,
                  (t_method)pvcompand_free,sizeof(t_pvcompand), 0,A_GIMME,0);
    CLASS_MAINSIGNALIN(c, t_pvcompand, x_f);
    class_addmethod(c,(t_method)pvcompand_dsp,gensym("dsp"), A_CANT, 0);
    class_addmethod(c,(t_method)pvcompand_mute,gensym("mute"),A_FLOAT,0);
    class_addmethod(c,(t_method)pvcompand_normalize,gensym("normalize"), A_FLOAT, 0);
    pvcompand_class = c;
    fftease_announce(OBJECT_NAME);
}

void pvcompand_mute(t_pvcompand *x, t_floatarg f)
{
    x->mute = (short)f;
}


void pvcompand_free( t_pvcompand *x ){
    if(x->fft->initialized){
        free(x->curthresh);
        free(x->atten);
        free(x->thresh);
    }
    fftease_free(x->fft);
    free(x->fft);
}

void *pvcompand_new(t_symbol *s, int argc, t_atom *argv)
{
    t_fftease *fft;
    t_pvcompand *x = (t_pvcompand *)pd_new(pvcompand_class);
    inlet_new(&x->x_obj, &x->x_obj.ob_pd,gensym("signal"), gensym("signal"));
    outlet_new(&x->x_obj, gensym("signal"));
    x->fft = (t_fftease *) calloc(1,sizeof(t_fftease));
    fft = x->fft;
    fft->initialized = 0;
    x->max_atten = -6.0;
    fft->N = FFTEASE_DEFAULT_FFTSIZE;
    fft->overlap = FFTEASE_DEFAULT_OVERLAP;
    fft->winfac = FFTEASE_DEFAULT_WINFAC;
    if(argc > 0){ fft->N = (int) atom_getfloatarg(0, argc, argv); }
    if(argc > 1){ fft->overlap = (int) atom_getfloatarg(1, argc, argv); }
    return x;
}

void pvcompand_init(t_pvcompand *x)
{
    t_fftease  *fft = x->fft;
    short initialized = x->fft->initialized;

    fftease_init(fft);

    if(!initialized){
        x->norml = 0;
        x->mute = 0;
        x->thresh_interval = 1.0;
        x->last_max_atten =  x->max_atten;
        x->atten_interval = 2.0 ;
        x->tstep = 1.0 ;
        x->gstep = 2.0 ;
        x->thresh = (t_float *) calloc((fft->N), sizeof(t_float));
        x->atten = (t_float *) calloc(fft->N, sizeof(t_float) );
        x->curthresh = (t_float *) calloc(fft->N, sizeof(t_float) );
    } else if(initialized == 1) {
        x->thresh = (t_float *) realloc(x->thresh, fft->N * sizeof(t_float));
        x->atten = (t_float *) realloc(x->atten, fft->N * sizeof(t_float));
        x->curthresh = (t_float *) realloc(x->curthresh, fft->N * sizeof(t_float));
    }
    update_thresholds(x);
}

void update_thresholds( t_pvcompand *x ) {
    int i;
    t_float nowamp = x->max_atten ;
    t_float nowthresh = 0.0 ;
    int N = x->fft->N;
    x->count = 0;
    if( nowamp < 0.0 ){
        while( nowamp < 0.0 ){
            x->atten[x->count] = pvcompand_ampdb( nowamp );
            nowamp += x->gstep ;
            ++(x->count);
            if(x->count >= N){
                pd_error(0, "count exceeds %d",N);
                x->count = N - 1;
                break;
            }
        }
    }
    else if( nowamp > 0.0 ){
        while( nowamp > 0.0 ){
            x->atten[x->count] = pvcompand_ampdb( nowamp );
            nowamp -= x->gstep ;
            ++(x->count);
            if(x->count >= N){
                pd_error(0, "count exceeds %d",N);
                x->count = N - 1;
                break;
            }
        }
    }
    for( i = 0; i < x->count; i++){
        x->thresh[i] = pvcompand_ampdb( nowthresh );
        nowthresh -= x->tstep ;
    }
}

void pvcompand_normalize(t_pvcompand *x, t_floatarg val)
{
    x->norml = (short)val;
}

static void do_pvcompand(t_pvcompand *x)
{
    t_fftease *fft = x->fft;
    t_float *channel = fft->channel;
    int N = fft->N;
    t_float *curthresh = x->curthresh;
    t_float *thresh = x->thresh;
    t_float *atten = x->atten;
    int count = x->count;
    t_float max_atten = x->max_atten;
    int i,j;
    t_float maxamp ;
    t_float cutoff;
    t_float avr, new_avr, rescale;

    fftease_fold(fft);
    fftease_rdft(fft,FFT_FORWARD);
    fftease_leanconvert(fft);

    maxamp = 0.;
    avr = 0;
    for( i = 0; i < N; i+= 2 ){
        avr += channel[i];
        if( maxamp < channel[i] ){
            maxamp = channel[i] ;
        }
    }
    if(count <= 1){
        //  post("count too low!");
        count = 1;
    }
    for( i = 0; i < count; i++ ){
        curthresh[i] = thresh[i]*maxamp ;
    }
    cutoff = curthresh[count-1];
    new_avr = 0;
    for( i = 0; i < N; i += 2){
        if( channel[i] > cutoff ){
            j = count-1;
            while( channel[i] > curthresh[j] ){
                j--;
                if( j < 0 ){
                    j = 0;
                    break;
                }
            }
            channel[i] *= atten[j];
        }
        new_avr += channel[i] ;
    }

    if( x->norml ) {
        if( new_avr <= 0 ){
            new_avr = .0001;
        }
        rescale =  avr / new_avr ;

    } else {
        rescale = pvcompand_ampdb( max_atten * -.5);
    }
    for( i = 0; i < N; i += 2){
        channel[i] *= rescale;
    }

    fftease_leanunconvert(fft);
    fftease_rdft(fft, FFT_INVERSE);
    fftease_overlapadd(fft);
}

t_int *pvcompand_perform(t_int *w)
{
    int i,j;
    t_pvcompand *x = (t_pvcompand *) (w[1]);
    t_float *MSPInputVector = (t_float *)(w[2]);
    t_float *in2 = (t_float *)(w[3]);
    t_float *MSPOutputVector = (t_float *)(w[4]);
    t_fftease *fft = x->fft;
    int D = fft->D;
    int Nw = fft->Nw;
    t_float *input = fft->input;
    t_float *output = fft->output;
    t_float mult = fft->mult;
    int MSPVectorSize = fft->MSPVectorSize;
    t_float *internalInputVector = fft->internalInputVector;
    t_float *internalOutputVector = fft->internalOutputVector;
    int operationRepeat = fft->operationRepeat;
    int operationCount = fft->operationCount;

    if(x->mute){
        for(i=0; i < MSPVectorSize; i++){ MSPOutputVector[i] = 0.0; }
        return w+5;
    }

    x->max_atten = *in2;
    if(x->max_atten != x->last_max_atten) {
        x->last_max_atten = x->max_atten;
        update_thresholds(x);
    }

    if( fft->bufferStatus == EQUAL_TO_MSP_VECTOR ){
        memcpy(input, input + D, (Nw - D) * sizeof(t_float));
        memcpy(input + (Nw - D), MSPInputVector, D * sizeof(t_float));

        do_pvcompand(x);

        for ( j = 0; j < D; j++ ){ *MSPOutputVector++ = output[j] * mult; }
        memcpy(output, output + D, (Nw-D) * sizeof(t_float));
        for(j = (Nw-D); j < Nw; j++){ output[j] = 0.0; }
    }
    else if( fft->bufferStatus == SMALLER_THAN_MSP_VECTOR ) {
        for( i = 0; i < operationRepeat; i++ ){
            memcpy(input, input + D, (Nw - D) * sizeof(t_float));
            memcpy(input + (Nw-D), MSPInputVector + (D*i), D * sizeof(t_float));

            do_pvcompand(x);

            for ( j = 0; j < D; j++ ){ *MSPOutputVector++ = output[j] * mult; }
            memcpy(output, output + D, (Nw-D) * sizeof(t_float));
            for(j = (Nw-D); j < Nw; j++){ output[j] = 0.0; }
        }
    }
    else if( fft->bufferStatus == BIGGER_THAN_MSP_VECTOR ) {
        memcpy(internalInputVector + (operationCount * MSPVectorSize), MSPInputVector,MSPVectorSize * sizeof(t_float));
        memcpy(MSPOutputVector, internalOutputVector + (operationCount * MSPVectorSize),MSPVectorSize * sizeof(t_float));
        operationCount = (operationCount + 1) % operationRepeat;

        if( operationCount == 0 ) {
            memcpy(input, input + D, (Nw - D) * sizeof(t_float));
            memcpy(input + (Nw - D), internalInputVector, D * sizeof(t_float));

            do_pvcompand(x);

            for ( j = 0; j < D; j++ ){ internalOutputVector[j] = output[j] * mult; }
            memcpy(output, output + D, (Nw - D) * sizeof(t_float));
            for(j = (Nw-D); j < Nw; j++){ output[j] = 0.0; }
        }
        fft->operationCount = operationCount;
    }
    return w+5;
}

t_float pvcompand_ampdb(t_float db)
{
    t_float amp;
    amp = pow((t_float)10.0, (t_float)(db/20.0)) ;
    return(amp);
}

void pvcompand_dsp(t_pvcompand *x, t_signal **sp)
{
    int reset_required = 0;
    int maxvectorsize = sp[0]->s_n;
    int samplerate = sp[0]->s_sr;

    if(!samplerate)
        return;
    t_fftease *fft = x->fft;
    if(fft->R != samplerate || fft->MSPVectorSize != maxvectorsize || fft->initialized == 0){
        reset_required = 1;
    }
    if(fft->MSPVectorSize != maxvectorsize){
        fft->MSPVectorSize = maxvectorsize;
        fftease_set_fft_buffers(fft);
    }
    if(fft->R != samplerate){
        fft->R = samplerate;
    }
    if(reset_required){
        pvcompand_init(x);
    }
    if(fftease_msp_sanity_check(fft,OBJECT_NAME)) {
        dsp_add(pvcompand_perform, 4, x, sp[0]->s_vec, sp[1]->s_vec, sp[2]->s_vec);
    }
}