ref: 22782a3553d1cbba3978f141a694c68b8d79e1b0
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 */