comparison tools/ftos.c @ 0:5242703e91d3 tip

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

+/*
+  ftos.c        binary float-to-short conversion.
+ --------
+
+*/
+
+#include <stdio.h>
+#include <math.h>
+#include "options.h"
+
+char applic[]     = "float to short data-type conversion." ;
+
+static char *helpstr, *errstr ;
+
+static Options option[] = {
+    {   "help"      ,   "off"       ,  &helpstr     ,   "help"          ,  DEBUG     },
+    {   "error"     ,   "off"       ,  &errstr      ,   "print overflow and quantization errors"  ,  VAL  },
+   ( char * ) 0 } ;
+
+
+#define MAX           32767.
+#define MIN        ( -32767. )
+
+main(argc, argv)
+int   argc ;
+char *argv[] ;
+{
+    FILE  *fp ;
+    float  X  ;
+    short  Y  ;
+    int    i  ;
+    float  min = MAX, fmin ;
+    float  max = MIN, fmax ;
+    float  quant, maxquant, sumquant=0 ;
+
+    fp = openopts( option,argc,argv ) ;
+    if ( !isoff( helpstr ) )
+	helpopts( helpstr, argv[0], applic, option ) ;
+
+    if ( isoff( errstr ) ) {
+
+	while ( fread( &X, sizeof(float), 1, fp ) ) {
+	    Y = (short)X ;
+	    fwrite( &Y, sizeof(short), 1, stdout);
+	}
+    }
+
+    else {
+
+	for ( i = 0 ; fread( &X, sizeof(float), 1, fp ) ; i++ ) {
+	    if ( X > max ) max = X ;
+	    if ( X < min ) min = X ;
+	    quant = ( X - (int)X ) / (int)( 1 + X ) ;
+	    sumquant += quant ;
+	    if ( quant > maxquant ) maxquant = quant ;
+	    Y = (short)X ;
+	    fwrite( &Y, sizeof(short), 1, stdout);
+	}
+
+	if ( max > MAX || min < MIN ) {
+
+	    if ( max > MAX )  fmax = MAX / max ;
+	    if ( min < MIN )  fmin = MIN / min ;
+
+	    if ( fmax < fmin ) fprintf( stderr, "16-bit overflow  (scale down by a factor < %f\n", fmax ) ;
+	    else               fprintf( stderr, "16-bit underflow  (scale down by a factor < %f\n", fmin ) ;
+	}
+	fprintf( stderr, "max  quantization error = %f\n", maxquant   ) ;
+	fprintf( stderr, "mean quantization error = %f\n", sumquant/i ) ;
+    }
+
+    fclose(fp);
+    exit(0);
+}
+
+