view tools/convert.c @ 0:5242703e91d3 tip

Initial checkin for AIM92 aimR8.2 (last updated May 1997).

/*
 convert.c
-----------
Convert <number><units> to new units given by the "to" option.
<units> are:
	p       sample points
	s       time in seconds
	ms      time in millisecs
	Hz      frequency in Hz
	kHz     frequency in kHz

Time in seconds or miliseconds is converted to and from sample points using
the given samplerate. Time (in seconds, miliseconds or samples) is converted
to and from frequency by reciprocal.

Example:

Convert 100 samples to time in ms, and the 10ms to a number of samples, both
at the default sample-rate of 20kHz. Then at a sample-rate of 10kHz print
the number of samples in 32ms.

    convert to=ms 100p to=p 10ms samplerate=10kHz to=p 32ms

Convert 0.1 seconds to sample points.

    convert -topoints 0.1sec
*/

#include <stdio.h>
#include <math.h>
#include "options.h"
#include "units.h"
#include "strmatch.h"

char applic[] = "Convert units: frequency, time, and sample numbers." ;
char usage[]  = "convert [options] arguments " ;

static char *helpstr, *debugstr, *sampstr, *tostr ;

static Options option[] = {
    {   "help"      ,   "off"       ,  &helpstr     ,   "help"                          , DEBUG   },
    {   "debug"     ,   "off"       ,  &debugstr    ,   "debugging switch"              , DEBUG   },
    {   "samplerate",   "20kHz"     ,  &sampstr     ,   "samplerate "                   , VAL     },
    {   "to"        ,   "points"    ,  &tostr       ,   "convert to <units>"            , VAL     },
   ( char * ) 0 } ;


int  samplerate ;

main(argc, argv)
int   argc ;
char *argv[] ;
{
    int  i, helpunits() ;

    i = argc ;
    while ( i > 0 ) {

	if ( i == argc )        /* first time, to account for prog name */
	    i = getopts( option, i, &argv[argc-i] ) ;
	else                    /* subsequent times */
	    i = getopts( option, i+1, &argv[argc-i-1] ) ;
	if ( !isoff( helpstr ) )
	    helpopts2( helpstr, argv[0], applic, usage, option, helpunits ) ;

	samplerate = to_Hz( sampstr, 0 ) ;

	for(  ; i > 0 && !isopt( argv[argc-i] ) ; --i )
	    convert( argv[argc-i] ) ;
    }
}


convert( s )
char *s ;
{
    switch ( listindex( units, tostr ) ) {
	case (-2) : fprintf(stderr,"ambiguous units [%s]\n", tostr ) ;
		    exit( 1 ) ;
	case (-1) : fprintf(stderr,"unknown units [%s]\n", tostr ) ;
		    exit( 1 ) ;
	case   0  : /* to points */
		    printf( "%dp\n"   , (int)to_p( s, samplerate  ) ) ;
		    break ;
	case   1  : /* to seconds */
		    printf( "%.3fs\n"   , to_s( s, samplerate  ) ) ;
		    break ;
	case   2  : /* to ms */
		    printf( "%.3fms\n"  , to_ms( s, samplerate ) ) ;
		    break ;
	case   3  : /* to Hz */
		    printf( "%.3fHz\n"  , to_Hz( s, samplerate   ) ) ;
		    break ;
	case   4  : /* to kHz */
		    printf( "%.3fkHz\n" , to_kHz( s, samplerate  ) ) ;
		    break ;
	case   5  : /* to ERB */
		    printf( "%.3ferb\n" , to_erb( s ) ) ;
		    break ;
    }
}


helpunits()
{
    fprintf(stderr,"\nunits: \n");
    fprintf(stderr,"            points      sample points     \n");
    fprintf(stderr,"            seconds     time in seconds   \n");
    fprintf(stderr,"            ms          time in millisecs \n");
    fprintf(stderr,"            Hz          frequency in Hz   \n");
    fprintf(stderr,"            kHz         frequency in kHz  \n");
    exit( 1 ) ;
}