shithub: sox

ref: b7c61db0a37cbc49d9195233143c640aad1b01d9
dir: /src/stat.c/

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/*
 * July 5, 1991
 * Copyright 1991 Lance Norskog And Sundry Contributors
 * This source code is freely redistributable and may be used for
 * any purpose.  This copyright notice must be maintained. 
 * Lance Norskog And Sundry Contributors are not responsible for 
 * the consequences of using this software.
 */

/*
 * Sound Tools statistics "effect" file.
 *
 * Build various statistics on file and print them.
 *
 * Output is unmodified from input.
 *
 */

#include <math.h>
#include <string.h>
#include "st_i.h"

/* Private data for STAT effect */
typedef struct statstuff {
	double	min, max, mid;
	double	asum;
	double	sum1, sum2;	/* amplitudes */
	double	dmin, dmax;
	double	dsum1, dsum2;	/* deltas */
	double	scale;		/* scale-factor    */
	double	last;		/* previous sample */
	ULONG	read;		/* samples processed */
	int	volume;
	int	srms;
	int	fft;
	ULONG   bin[4];
	double  *re;
	double  *im;
	ULONG   fft_bits;
	ULONG   fft_size;
	ULONG   fft_offset;
} *stat_t;


/*
 * Process options
 */
int st_stat_getopts(eff_t effp, int n, char **argv) 
{
	stat_t stat = (stat_t) effp->priv;

	stat->scale = MAXLONG;
	stat->volume = 0;
	stat->srms = 0;
	stat->fft = 0;

	while (n>0)
	{
		if (!(strcmp(argv[0], "-v"))) 
		{
			stat->volume = 1;
		}
		else if (!(strcmp(argv[0], "-s"))) 
		{
			double scale;

			if (n <= 1) 
			{
			  st_fail("-s option: invalid argument");
			  return (ST_EOF);
			}
			if (!sscanf(argv[1], "%lf", &scale))
			{
			  st_fail("-s option: invalid argument");
			  return (ST_EOF);
			}
			stat->scale = scale;

			/* Two option argument.  Account for this */
	                --n; ++argv;
		}
		else if (!(strcmp(argv[0], "-rms"))) 
		{
			stat->srms = 1;
		}
		else if (!(strcmp(argv[0], "-freq"))) 
		{
			stat->fft = 1;
		}
		else if (!(strcmp(argv[0], "-d"))) {
			stat->volume = 2;
		}
		else
		{
			st_fail("Summary effect: unknown option");
			return(ST_EOF);
		}
	        --n; ++argv;
	}
	return (ST_SUCCESS);
}

/*
 * Prepare processing.
 */
int st_stat_start(eff_t effp)
{
	stat_t stat = (stat_t) effp->priv;
	int i;
	LONG  bitmask;

	stat->min = stat->max = stat->mid = 0;
	stat->asum = 0;
	stat->sum1 = stat->sum2 = 0;

	stat->dmin = stat->dmax = 0;
	stat->dsum1 = stat->dsum2 = 0;

	stat->last = 0;
	stat->read = 0;

	for (i = 0; i < 4; i++)
		stat->bin[i] = 0;

	stat->fft_size = 4096;
	stat->re = 0;
	stat->im = 0;

	if (stat->fft)
	{
	    bitmask = 0x80000000L;
	    stat->fft_bits = 31;
	    stat->fft_offset = 0;
	    while (bitmask && !(stat->fft_size & bitmask))
	    {
		bitmask = bitmask >> 1;
		stat->fft_bits--;
	    }

	    if (bitmask && (stat->fft_size & ~bitmask))
	    {
		st_fail("FFT can only use sample buffers of 2^n. Buffer size used is %ld\n",stat->fft_size);
		return(ST_EOF);
	    }

	    stat->re = malloc(sizeof(double) * stat->fft_size);
	    stat->im = malloc(sizeof(double) * stat->fft_size);

	    if (!stat->re || !stat->im)
	    {
		st_fail("Unable to allocate memory for FFT buffers.\n");
		return (ST_EOF);
	    }
	}

	return (ST_SUCCESS);
}

/*
 * Processed signed long samples from ibuf to obuf.
 * Return number of samples processed.
 */

extern int FFT(short dir,long m,double *x,double *y);

int st_stat_flow(eff_t effp, st_sample_t *ibuf, st_sample_t *obuf, 
                 st_size_t *isamp, st_size_t *osamp)
{
	stat_t stat = (stat_t) effp->priv;
	int len, done, x, x1;
	short count;
        float magnitude;
        float ffa;

	count = 0;
	len = ((*isamp > *osamp) ? *osamp : *isamp);
	if (len==0) return (ST_SUCCESS);

	if (stat->read == 0)	/* 1st sample */
		stat->min = stat->max = stat->mid = stat->last = (*ibuf)/stat->scale;

	if (stat->fft)
	{
            for (x = 0; x < len; x++)
            {
		stat->re[stat->fft_offset] = ibuf[x];
		stat->im[stat->fft_offset++] = 0;

		if (stat->fft_offset >= stat->fft_size)
		{
		    stat->fft_offset = 0;
	            FFT(1,stat->fft_bits,stat->re,stat->im);
	            ffa = (float)effp->ininfo.rate/stat->fft_size;
	            for (x1= 0; x1 < stat->fft_size/2; x1++)
	            {
	                if (x1 == 0 || x1 == 1)
	                {
		            magnitude = 0.0; /* no DC */
	                }
	                else
	                {
		            magnitude = sqrt(stat->re[x1]*stat->re[x1] + stat->im[x1]*stat->im[x1]);
		            if (x1 == (stat->fft_size/2) - 1)
		                magnitude *= 2.0;
	                }
	                fprintf(stderr,"%f  %f\n",ffa*x1, magnitude);
	            }
		}

	    }
	}


	for(done = 0; done < len; done++) {
		long lsamp;
		double samp, delta;
		/* work in scaled levels for both sample and delta */
		lsamp = *ibuf++;
		samp = (double)lsamp/stat->scale;
		stat->bin[RIGHT(lsamp,30)+2]++;
		*obuf++ = lsamp;


		if (stat->volume == 2)
		{
		    fprintf(stderr,"%08lx ",lsamp);
		    if (count++ == 5)
		    {
			fprintf(stderr,"\n");
			count = 0;
		    }
		}

		/* update min/max */
		if (stat->min > samp)
			stat->min = samp;
		else if (stat->max < samp)
			stat->max = samp;
		stat->mid = stat->min / 2 + stat->max / 2;

		stat->sum1 += samp;
		stat->sum2 += samp*samp;
		stat->asum += fabs(samp);
		
		delta = fabs(samp - stat->last);
		if (delta < stat->dmin)
			stat->dmin = delta;
		else if (delta > stat->dmax)
			stat->dmax = delta;

		stat->dsum1 += delta;
		stat->dsum2 += delta*delta;

		stat->last = samp;
	}
	stat->read += len;
	*isamp = *osamp = len;
	/* Process all samples */
	return (ST_SUCCESS);
}

/*
 * Process tail of input samples.
 */
int st_stat_drain(eff_t effp, st_sample_t *obuf, st_size_t *osamp)
{
    stat_t stat = (stat_t) effp->priv;
    int x;
    float magnitude;
    float ffa;

    /* When we run out of samples, then we need to pad buffer with
     * zeros and then run FFT one last time.  Only perform this
     * operation if there are at least 1 sample in the buffer.
     */

    if (stat->fft && stat->fft_offset)
    {
	/* When we run out of samples, then we need to pad buffer with
	 * zeros and then run FFT one last time.  Only perform this
	 * operation if there are at least 1 sample in the buffer.
	 */
        for (x = stat->fft_offset; x < stat->fft_size; x++)
        {
	    stat->re[x] = 0;
	    stat->im[x] = 0;
        }
        FFT(1,stat->fft_bits,stat->re,stat->im);
	ffa = (float)effp->ininfo.rate/stat->fft_size;
	for (x=0; x < stat->fft_size/2; x++)
	{
	    if (x == 0 || x == 1)
	    {
		magnitude = 0.0; /* no DC */
	    }
	    else
	    {
		magnitude = sqrt(stat->re[x]*stat->re[x] + stat->im[x]*stat->im[x]);
		if (x != (stat->fft_size/2) - 1)
		    magnitude *= 2.0;
	    }
	    fprintf(stderr, "%f  %f\n",ffa*x, magnitude);
	}
    }

    *osamp = 0;
    return (ST_SUCCESS);
}

/*
 * Do anything required when you stop reading samples.  
 * Don't close input file! 
 */
int st_stat_stop(eff_t effp)
{
	stat_t stat = (stat_t) effp->priv;
	double amp, scale, rms = 0, freq;
	double x, ct;

	ct = stat->read;

	if (stat->srms) {  /* adjust results to units of rms */
		double f;
		rms = sqrt(stat->sum2/ct);
		f = 1.0/rms;
		stat->max *= f;
		stat->min *= f;
		stat->mid *= f;
		stat->asum *= f;
		stat->sum1 *= f;
		stat->sum2 *= f*f;
		stat->dmax *= f;
		stat->dmin *= f;
		stat->dsum1 *= f;
		stat->dsum2 *= f*f;
		stat->scale *= rms;
	}

	scale = stat->scale;

	amp = -stat->min;
	if (amp < stat->max)
		amp = stat->max;

	/* Just print the volume adjustment */
	if (stat->volume == 1 && amp > 0) {
		fprintf(stderr, "%.3f\n", MAXLONG/(amp*scale));
		return (ST_SUCCESS);
	}
	if (stat->volume == 2) {
		fprintf(stderr, "\n\n");
	}
	/* print out the info */
	fprintf(stderr, "Samples read:      %12lu\n", stat->read);
	fprintf(stderr, "Length (seconds):  %12.6f\n", (double)stat->read/effp->ininfo.rate/effp->ininfo.channels);
	if (stat->srms)
		fprintf(stderr, "Scaled by rms:     %12.6f\n", rms);
	else
		fprintf(stderr, "Scaled by:         %12.1f\n", scale);
	fprintf(stderr, "Maximum amplitude: %12.6f\n", stat->max);
	fprintf(stderr, "Minimum amplitude: %12.6f\n", stat->min);
	fprintf(stderr, "Midline amplitude: %12.6f\n", stat->mid);
	fprintf(stderr, "Mean    norm:      %12.6f\n", stat->asum/ct);
	fprintf(stderr, "Mean    amplitude: %12.6f\n", stat->sum1/ct);
	fprintf(stderr, "RMS     amplitude: %12.6f\n", sqrt(stat->sum2/ct));

	fprintf(stderr, "Maximum delta:     %12.6f\n", stat->dmax);
	fprintf(stderr, "Minimum delta:     %12.6f\n", stat->dmin);
	fprintf(stderr, "Mean    delta:     %12.6f\n", stat->dsum1/(ct-1));
	fprintf(stderr, "RMS     delta:     %12.6f\n", sqrt(stat->dsum2/(ct-1)));
	freq = sqrt(stat->dsum2/stat->sum2)*effp->ininfo.rate/(M_PI*2);
	fprintf(stderr, "Rough   frequency: %12d\n", (int)freq);

	if (amp>0) fprintf(stderr, "Volume adjustment: %12.3f\n", MAXLONG/(amp*scale));

        if (stat->bin[2] == 0 && stat->bin[3] == 0)
                fprintf(stderr, "\nProbably text, not sound\n");
        else {

                x = (float)(stat->bin[0] + stat->bin[3]) / (float)(stat->bin[1] + stat->bin[2]);

                if (x >= 3.0)                  /* use opposite encoding */
		{
                        if (effp->ininfo.encoding == ST_ENCODING_UNSIGNED)
			{
                                fprintf (stderr,"\nTry: -t raw -b -s \n");
			}
                        else
			{
                                fprintf (stderr,"\nTry: -t raw -b -u \n");
			}

		}
                else if (x <= 1.0/3.0)
		{ 
		    ;;              /* correctly decoded */
		}
                else if (x >= 0.5 && x <= 2.0)       /* use ULAW */
		{
                        if (effp->ininfo.encoding == ST_ENCODING_ULAW)
			{
                                fprintf (stderr,"\nTry: -t raw -b -u \n");
			}
                        else
			{
                                fprintf (stderr,"\nTry: -t raw -b -U \n");
			}
		}
                else    
		{
                        fprintf (stderr, "\nCan't guess the type\n");
		}
        }

	/* Release FFT memory if allocated */
	if (stat->re)
	    free((void *)stat->re);
	if (stat->im)
	    free((void *)stat->im);

	return (ST_SUCCESS);

}


/*
   This computes an in-place complex-to-complex FFT 
   x and y are the real and imaginary arrays of 2^(m-1) points.
   dir =  1 gives forward transform
   dir = -1 gives reverse transform 
*/
int FFT(dir,m,re,im)
short dir;
long m;
double *re,*im;
{
   long n,i,i1,j,k,i2,l,l1,l2;
   double c1,c2,tre,tim,t1,t2,u1,u2,z;

   /* Calculate the number of points */
   n = 1;
   for (i=0;i<m;i++) 
      n *= 2;

   /* Do the bit reversal */
   i2 = n >> 1;

   j = 0;

   for (i=0;i<n-1;i++) {
      if (i < j) {
         tre = re[i];
         tim = im[i];
         re[i] = re[j];
         im[i] = im[j];
         re[j] = tre;
         im[j] = tim;
      }
      k = i2;
      while (k <= j) {
         j -= k;
         k >>= 1;
      }
      j += k;
   }

   /* Compute the FFT */
   c1 = -1.0; 
   c2 = 0.0;
   l2 = 1;
   for (l=0;l<m;l++) {
      l1 = l2;
      l2 <<= 1;
      u1 = 1.0; 
      u2 = 0.0;
      for (j=0;j<l1;j++) {
         for (i=j;i<n;i+=l2) {
            i1 = i + l1;
            t1 = u1 * re[i1] - u2 * im[i1];
            t2 = u1 * im[i1] + u2 * re[i1];
            re[i1] = re[i] - t1; 
            im[i1] = im[i] - t2;
            re[i] += t1;
            im[i] += t2;
         }
         z =  u1 * c1 - u2 * c2;
         u2 = u1 * c2 + u2 * c1;
         u1 = z;
      }
      c2 = sqrt((1.0 - c1) / 2.0);
      if (dir == 1) 
         c2 = -c2;
      c1 = sqrt((1.0 + c1) / 2.0);
   }

   /* Scaling for forward transform */
   if (dir == 1) {
      for (i=0;i<n;i++) {
         re[i] /= n;
         im[i] /= n;
      }
   }

   return ST_SUCCESS;
}