ref: 98267de439714fcdff94c9588f34fb8a67df70c1
dir: /sound2sun.c/
/************************************************************************/
/* Copyright 1989 by Rich Gopstein and Harris Corporation */
/* */
/* Permission to use, copy, modify, and distribute this software */
/* and its documentation for any purpose and without fee is */
/* hereby granted, provided that the above copyright notice */
/* appears in all copies and that both that copyright notice and */
/* this permission notice appear in supporting documentation, and */
/* that the name of Rich Gopstein and Harris Corporation not be */
/* used in advertising or publicity pertaining to distribution */
/* of the software without specific, written prior permission. */
/* Rich Gopstein and Harris Corporation make no representations */
/* about the suitability of this software for any purpose. It */
/* provided "as is" without express or implied warranty. */
/************************************************************************/
/************************************************************************/
/* sound2sun.c - Convert sampled audio files into uLAW format for the */
/* Sparcstation 1. */
/* Send comments to ..!rutgers!soleil!gopstein */
/************************************************************************/
/* */
/* Modified November 27, 1989 to convert to 8000 samples/sec */
/* (contrary to man page) */
/* Modified December 13, 1992 to write standard Sun .au header with */
/* unspecified length. Also made miscellaneous changes for */
/* VMS port. (K. S. Kubo, ken@hmcvax.claremont.edu) */
/* Fixed Bug with converting slow sample speeds */
/* */
/************************************************************************/
#include <stdio.h>
#define DEFAULT_FREQUENCY 11000
#ifdef VAXC
#define READ_OPEN "r", "mbf=16", "shr=get"
#define WR_OPEN "w", "mbf=16"
#else
#define READ_OPEN "r"
#define WR_OPEN "w"
#endif
FILE *infile, *outfile;
/* convert two's complement ch into uLAW format */
unsigned int cvt(ch)
int ch;
{
int mask;
if (ch < 0) {
ch = -ch;
mask = 0x7f;
} else {
mask = 0xff;
}
if (ch < 32) {
ch = 0xF0 | 15 - (ch / 2);
} else if (ch < 96) {
ch = 0xE0 | 15 - (ch - 32) / 4;
} else if (ch < 224) {
ch = 0xD0 | 15 - (ch - 96) / 8;
} else if (ch < 480) {
ch = 0xC0 | 15 - (ch - 224) / 16;
} else if (ch < 992) {
ch = 0xB0 | 15 - (ch - 480) / 32;
} else if (ch < 2016) {
ch = 0xA0 | 15 - (ch - 992) / 64;
} else if (ch < 4064) {
ch = 0x90 | 15 - (ch - 2016) / 128;
} else if (ch < 8160) {
ch = 0x80 | 15 - (ch - 4064) / 256;
} else {
ch = 0x80;
}
return (mask & ch);
}
/* write a "standard" sun header with an unspecified length */
#define wrulong(fp, ul) putc((ul >> 24) & 0xff, fp); \
putc((ul >> 16) & 0xff, fp); putc((ul >> 8) & 0xff, fp); \
putc(ul & 0xff, fp);
static void
wr_header(optr)
FILE *optr;
{
wrulong(optr, 0x2e736e64); /* Sun magic */
wrulong(optr, 24); /* header size in bytes */
wrulong(optr, ((unsigned)(~0))); /* unspecified data size */
wrulong(optr, 1); /* Sun uLaw format */
wrulong(optr, 8000); /* sample rate by definition :-) */
wrulong(optr, 1); /* single channel */
}
/*******************************************************
/* */
/* Usage is "sound2sun [-f frequency] infile outfile" */
/* */
/* "frequency" is the samples per second of the infile */
/* the outfile is always 8000 samples per second. */
/* */
/*******************************************************/
/***********************************************************************/
/* */
/* The input file is expected to be a stream of one-byte excess-128 */
/* samples. Each sample is converted to 2's complement by subtracting */
/* 128, then converted to uLAW and output. We calculate the proper */
/* number of input bytes to skip in order to make the sample frequency */
/* convert to 8000/sec properly. Interpolation could be added, but it */
/* doesn't appear to be necessary. */
/* */
/***********************************************************************/
main(argc, argv)
int argc;
char *argv[];
{
float sum = 0;
float frequency, increment;
unsigned char ch;
unsigned char ulaw;
int chr;
if ((argc != 3) && (argc != 5)) {
fprintf(stderr,"Usage: sound2sun [-f frequency] infile outfile\n");
exit(1);
}
if (argc == 5) {
if (strcmp(argv[1], "-f") != 0) {
fprintf(stderr, "Usage: sound2sun [-f frequency] infile outfile\n");
exit(1);
} else {
frequency = atoi(argv[2]);
}
} else {
frequency = DEFAULT_FREQUENCY;
}
if ((infile = fopen(argv[argc-2], READ_OPEN)) == NULL) {
perror("Error opening infile");
exit(0);
}
if ((outfile = fopen(argv[argc-1], WR_OPEN)) == NULL) {
perror("Error opening outfile");
exit(0);
}
wr_header(outfile);
/* increment is the number of bytes to read each time */
increment = frequency / 8000;
ch = fgetc(infile);
while (!feof(infile)) {
/* convert the excess 128 to two's complement */
chr = 0x80 - ch;
/* increase the volume */
/* convert to uLAW */
ulaw = cvt(chr * 16);
/* output it */
fputc((char) ulaw, outfile);
/* skip enough input bytes to compensate for sampling frequency diff */
sum += increment;
while(sum > 0) {
if (!feof(infile)) ch = fgetc(infile);
sum--;
}
}
fclose(infile);
fclose(outfile);
}
/* DEC/CMS REPLACEMENT HISTORY, Element SOUND2SUN.C */
/* *1 14-DEC-1992 17:46:37 CENYDD "main program" */
/* DEC/CMS REPLACEMENT HISTORY, Element SOUND2SUN.C */