guido@cwi.nl (Guido van Rossum) (07/27/90)
We just discovered /dev/audio in IRIX 3.2 for the PI, but there seem to be no standard programs to use it. Anybody got interesting software to apply this? Or even pointers? Guido van Rossum, Centre for Mathematics and Computer Science (CWI), Amsterdam guido@cwi.nl or ..!hp4nl!cwi.nl!guido or guido%cwi.nl@uunet.uu.net "He used to be a euphemism, now he's just a friend"
" ratcliffe) (07/28/90)
In article <guido.649079335@piring.cwi.nl> guido@cwi.nl (Guido van Rossum) writes: >We just discovered /dev/audio in IRIX 3.2 for the PI, but there seem to >be no standard programs to use it. Anybody got interesting software to >apply this? Or even pointers? in 3.3.1 (coming "soon" to your town) we've got 1 (sorry, only 1 for now...) audio prog down in /usr/people/4Dgifts/examples/audio. to tide you over, the Makefile, README, and audio.c files follow: *************** /usr/people/4Dgifts/examples/audio/Makefile: SHELL = /bin/sh PROGS=audio CFLAGS= -O -s all: $(PROGS) clean: rm -f *.o $(PROGS) .c: $(CC) $(CFLAGS) -o $@ $< $(LDFLAGS) *************** /usr/people/4Dgifts/examples/audio/README: README for audio programming examples The capability for audio input/output currently only exists on 4D/2* machines (i.e. Personal IRIS machines ONLY). Admittedly, information about this functionality is sparse, but things WILL be improving fairly soon now. At this stage, a little bit of source code example is better than none... audio.c: demos how to digitally record microphone input to a Personal IRIS (4D/20 or 4D/25) and place the data into a file, as well as playing back the sounds already recorded. *************** /usr/people/4Dgifts/examples/audio/audio.c: /* * audio.c: * * This test program was initially written to demonstrate how one would * digitally record microphone input to a Personal Iris and place the data * into a file (execute "audio -i -opts"). Alternately, you can play back * the sounds or voice that you have recorded (execute "audio -o -opts"). * All that is needed to use this program is an 8 ohm speaker connected to * the audio output and a 600 ohm microphone connected to the microphone * input. The other audio input may be used to connect a higher level audio * signal that doesn't require pre-amplification. * * resusitated by (& hats off to) Frank Demcak -- February, 1990 */ #include <stdio.h> #include <fcntl.h> #include <sys/audio.h> main(argc, argv) int argc; char *argv[]; { int size, gain=100, rate=2, iflag, oflag, gflag, sflag, fflag,rflag; char *file, *buffer; int in, out, audio,i; if ( argc == 1 ) { usage: fprintf(stderr,"usage: %s -i [-g (0-255)gain] ", argv[0]); fprintf(stderr,"[-r (0-3)rate] -f file [-s size]\n"); fprintf(stderr," %s -o [-g (0-255)gain] ", argv[0]); fprintf(stderr,"[-r (0-3)rate] -f file [-s size]\n"); exit(1); } /* Parse the record/playback options */ for ( i = 1; i < argc; i++ ) { if ( !strcmp(argv[i],"-i") ) iflag++; else if ( !strcmp(argv[i],"-o") ) oflag++; else if ( !strcmp(argv[i],"-g") ) { gflag++; gain = atoi(argv[++i]); } else if ( !strcmp(argv[i],"-r") ) { rflag++; rate = atoi(argv[++i]); } else if ( !strcmp(argv[i],"-f") ) { fflag++; file = argv[++i]; } else if ( !strcmp(argv[i],"-s") ) { sflag++; size = atoi(argv[++i]); } else goto usage; } /* Open input or output file for record/playback */ if ( iflag ) { if (fflag) { /* Create a Read Write file and set permissions */ out = open(file, O_CREAT|O_RDWR); chmod (file,00666); } else out = 1; } else if ( oflag ) { if (fflag) /* Just open file for reading */ in = open(file, O_RDONLY); else in = 0; } else { fprintf(stderr, "must specify one of -o or -i\n"); exit(1); } /* printf test diag statements printf("iflag=%i\n",iflag); printf("oflag=%i\n",oflag); printf("gflag=%i\n",gflag); printf(" gain =%d\n",gain); printf("rflag=%i\n",rflag); printf(" rate =%d\n",rate); printf("fflag=%i\n",fflag); printf(" file Name=%s\n",file); printf("sflag=%i\n",sflag); printf(" file size=%d\n",size); */ /* Open audio port as a character device */ audio = open( "/dev/audio", O_RDWR ); /* This part doesn't seem to work as advertised */ /* Investigating how to turn off output while input is being recorded */ if ( gflag ) if ( iflag ) { ioctl(audio, AUDIOCSETINGAIN, gain); ioctl(audio, AUDIOCSETOUTGAIN, 0); } else { ioctl(audio, AUDIOCSETINGAIN, 0); ioctl(audio, AUDIOCSETOUTGAIN, gain); } /* set audio sampling rate 0=none?,1=8k,2=16k,3=32k samples per sec */ if ( rflag ) ioctl(audio, AUDIOCSETRATE, rate); if ( iflag ) { if ( ! sflag ) { fprintf(stderr,"must set a size for input\n"); exit (1); } buffer = (char *)malloc( size ); if ( ! buffer ) { fprintf(stderr,"unable to get %d byte buffer\n",size); exit(1); } read(audio,buffer,size); write(out,buffer,size); } else { /* Assume this is an sound output request */ /* Default buffer size = 16k if nothing is specified */ if ( ! sflag ) size = 16536; buffer = (char *)malloc( size ); if ( ! buffer ) { fprintf(stderr,"unable to get %d byte buffer\n",size); exit(1); } /* Write to audio port the contents of specified file until EOF This can be improved for simultaneous read/writes Insert user customization for specific file or usr needs i.e. while (read(in,buffer,size)!=EOF) write (audio,buffer,size); */ read (in,buffer,size); write(audio,buffer,size); } close(file); }