Category : C Source Code
Archive   : SOX.ZIP
Filename : STAT.C

 
Output of file : STAT.C contained in archive : SOX.ZIP

/*
* 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.
* No output.
*/

#include "st.h"

/* Private data for STAT effect */
typedef struct statstuff {
long min, max, mean; /* amplitudes */
long dmin, dmax, dmean; /* deltas */
long last; /* previous sample */
int first;
int total;
int volume;
unsigned long bin[4];
} *stat_t;

#define abs(val) (((val) < 0) ? -(val) : (val))

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

stat->volume = 0;
if (n)
if (strcmp(argv[0], "-V"))
stat->volume = 1;
else
fail("Summary effect takes no options.");
}

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

stat->min = stat->dmin = 0x7fffffff;
stat->max = stat->dmax = 0x80000000;
stat->first = 1;

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

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

stat_flow(effp, ibuf, obuf, isamp, osamp)
eff_t effp;
long *ibuf, *obuf;
int *isamp, *osamp;
{
stat_t stat = (stat_t) effp->priv;
int len, done;
long samp, delta;

len = ((*isamp > *osamp) ? *osamp : *isamp);
for(done = 0; done < len; done++) {
/* work in absolute levels for both sample and delta */
samp = *ibuf++;
*obuf++ = samp;

stat->bin[RIGHT(samp,30)+2]++;

samp = abs(samp);
if (samp < stat->min)
stat->min = samp;
if (samp > stat->max)
stat->max = samp;
if (stat->first) {
stat->first = 0;
stat->mean = samp;
stat->dmean = 0;
} else {
/* overflow avoidance */
if ((stat->mean > 0x20000000) || (samp > 0x20000000))
stat->mean = stat->mean/2 + samp/2;
else
stat->mean = (stat->mean + samp)/2;

delta = abs(samp - stat->last);
if (delta < stat->dmin)
stat->dmin = delta;
if (delta > stat->dmax)
stat->dmax = delta;
/* overflow avoidance */
if ((delta > 0x20000000) || (stat->dmean > 0x20000000))
stat->dmean = stat->dmean/2 + delta/2;
else
stat->dmean = (stat->dmean + delta)/2;
}
stat->last = samp;
}
/* Process all samples */
}

/*
* Do anything required when you stop reading samples.
* Don't close input file!
*/
void
stat_stop(effp)
eff_t effp;
{
stat_t stat = (stat_t) effp->priv;
double amp, range;
int i;
float x;

stat->min = RIGHT(stat->min, 16);
stat->max = RIGHT(stat->max, 16);
stat->mean = RIGHT(stat->mean, 16);
stat->dmin = RIGHT(stat->dmin, 16);
stat->dmax = RIGHT(stat->dmax, 16);
stat->dmean = RIGHT(stat->dmean, 16);

range = 32767.0;

amp = - stat->min;
if (amp < stat->max)
amp = stat->max;
/* Just print the volume adjustment */
if (stat->volume) {
fprintf(stderr, "%.3f\n", 32767.0/amp);
return;
}
/* print them out */
fprintf(stderr, "Maximum amplitude: %.3f\n", stat->max/range);
fprintf(stderr, "Minimum amplitude: %.3f\n", stat->min/range);
fprintf(stderr, "Mean amplitude: %.3f\n", stat->mean/range);

fprintf(stderr, "Maximum delta: %.3f\n", stat->dmax/range);
fprintf(stderr, "Minimum delta: %.3f\n", stat->dmin/range);
fprintf(stderr, "Mean delta: %.3f\n", stat->dmean/range);

fprintf(stderr, "Volume adjustment: %.3f\n", 32767.0/amp);

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 style */
if (effp->ininfo.style == UNSIGNED)
printf ("\nTry: -t raw -b -s \n");
else
printf ("\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.style == ULAW)
printf ("\nTry: -t raw -b -u \n");
else
printf ("\nTry: -t raw -b -U \n");

else
fprintf (stderr, "\nCan't guess the type\n");
}

}



  3 Responses to “Category : C Source Code
Archive   : SOX.ZIP
Filename : STAT.C

  1. Very nice! Thank you for this wonderful archive. I wonder why I found it only now. Long live the BBS file archives!

  2. This is so awesome! 😀 I’d be cool if you could download an entire archive of this at once, though.

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