This is perso_b.c in view mode; [Download] [Up]
//Written by J. Laroche at the Center for Music Experiment at UCSD, San Diego //California. December 1990.
// An example of how to play a sound through the DSP. We pass the sample using
// a non DMA protocol, which may cause drop outs to occur, especially if the
// sound file is 44100 stereo.
// To improve it, we can set-up more buffers in the driver (16 instead of just
// 4), at the cost of real time (there will be a longer delay between the time
// the first samples were sent and the time you'll hear them.)
// If the sound is mono, we pass a host command to the DSP to tell it to
// duplicate every sample, since the stream to the DACs has to be stereo.
#import <sound/sound.h>
#import <sound/sounddriver.h>
#import <mach.h>
#import <stdio.h>
#define Error(A,B) if((A)) {fprintf(stderr,"%s %s\n",B, SNDSoundError((A)));\
mach_error(B,(A)); }
#define DMASIZE 2048
static void read_completed(void *arg, int ta)
{
fprintf(stderr,"playing completed \n");
exit(0);
}
static void read_started(void *arg, int tag)
{
fprintf(stderr,"Playing Started \n");
}
void main (int argc, char *argv[])
{
int i;
static port_t dev_port, owner_port;
static port_t reply_port, write_port,cmd_port;
kern_return_t k_err;
snddriver_handlers_t handlers = { 0, 0,
read_started,read_completed,0,0,0, 0, 0};
msg_header_t *reply_msg;
SNDSoundStruct *sound;
SNDSoundStruct *dspStruct;
short *location;
int low_water = 48*1024;
int high_water = 64*1024;
int WRITE_TAG = 1;
int length,protocol;
int low_SR = 0;
int stereo = 0;
if(argc == 1) { printf("I need a 16bit linear sound file...\n");
exit(1);}
k_err = SNDAcquire(SND_ACCESS_OUT|SND_ACCESS_DSP,0,0,0,
NULL_NEGOTIATION_FUN,0,&dev_port,&owner_port);
Error(k_err,"SND acquisition ");
k_err = port_allocate(task_self(),&reply_port);
k_err = snddriver_get_dsp_cmd_port(dev_port,owner_port,&cmd_port);
// To give us more headroom, we can force the driver to set-up more buffers.
k_err = snddriver_set_sndout_bufcount(dev_port,owner_port,16);
Error(k_err,"Buff count ");
k_err = SNDReadSoundfile(argv[1], &sound);
Error(k_err,argv[1]);
low_SR = (sound->samplingRate == SND_RATE_LOW);
stereo = (sound->channelCount == 2);
printf("Playing at %d Hz %s\n",((low_SR)?22050:44100),((stereo)?
"stereo":"mono"));
k_err = SNDGetDataPointer(sound,(char**)&location,&length,&i);
Error(k_err,"Data Pointer");
protocol = SNDDRIVER_DSP_PROTO_RAW;
k_err = snddriver_stream_setup(dev_port, owner_port,((low_SR) ?
SNDDRIVER_STREAM_THROUGH_DSP_TO_SNDOUT_22:
SNDDRIVER_STREAM_THROUGH_DSP_TO_SNDOUT_44),
DMASIZE, 2,
low_water, high_water,
&protocol, &write_port);
Error(k_err,"Stream ");
k_err = snddriver_dsp_protocol(dev_port, owner_port, protocol);
Error(k_err,"Protocol");
k_err = SNDReadDSPfile("perso_b.lod", &dspStruct, NULL);
Error(k_err,"DSP file");
k_err = SNDBootDSP(dev_port, owner_port, dspStruct);
Error(k_err,"DSP BOOT");
if(!stereo)
k_err = snddriver_dsp_host_cmd(cmd_port,20,SNDDRIVER_LOW_PRIORITY);
k_err = snddriver_stream_start_writing(write_port,location,
length, WRITE_TAG,0,0,1,1,0,0,0,0, reply_port);
Error(k_err,"Write Command ");
reply_msg = (msg_header_t *)malloc(MSG_SIZE_MAX);
while (1)
{
reply_msg->msg_size = MSG_SIZE_MAX;
reply_msg->msg_local_port = reply_port;
k_err = msg_receive(reply_msg, MSG_OPTION_NONE, 0);
if(!k_err) snddriver_reply_handler(reply_msg,&handlers);
}
}
These are the contents of the former NiCE NeXT User Group NeXTSTEP/OpenStep software archive, currently hosted by Netfuture.ch.