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#include <stdio.h>
#include <stdlib.h>
#include <unistd.h>
#include "portmidi.h"
#include "porttime.h"
#include "pminternal.h"
#define LATENCY 0
#define NUM_ECHOES 10
int
main()
{
int i = 0;
int n = 0;
PmStream *midi_in;
PmStream *midi_out;
PmError err;
char line[80];
PmEvent buffer[NUM_ECHOES];
int transpose;
int delay;
int status, data1, data2;
int statusprefix;
/* always start the timer before you start midi */
Pt_Start(1, 0, 0); /* start a timer with millisecond accuracy */
for (i = 0; i < Pm_CountDevices(); i++) {
const PmDeviceInfo *info = Pm_GetDeviceInfo(i);
printf("%d: %s, %s", i, info->interf, info->name);
if (info->input) printf(" (input)");
if (info->output) printf(" (output)");
printf("\n");
}
/* OPEN INPUT DEVICE */
printf("Type input number: ");
while (n != 1) {
n = scanf("%d", &i);
gets(line);
}
err = Pm_OpenInput(&midi_in, i, NULL, 100, NULL, NULL, NULL);
if (err) {
printf("could not open midi device: %s\n", Pm_GetErrorText(err));
exit(1);
}
printf("Midi Input opened.\n");
/* OPEN OUTPUT DEVICE */
printf("Type output number: ");
n = 0;
while (n != 1) {
n = scanf("%d", &i);
gets(line);
}
err = Pm_OpenOutput(&midi_out, i, NULL, 0, NULL, NULL, LATENCY);
if (err) {
printf("could not open midi device: %s\n", Pm_GetErrorText(err));
exit(1);
}
printf("Midi Output opened with %d ms latency.\n", LATENCY);
/* Get input from user for parameters */
printf("Type number of milliseconds for echoes: ");
n = 0;
while (n != 1) {
n = scanf("%d", &delay);
gets(line);
}
printf("Type number of semitones to transpose up: ");
n = 0;
while (n != 1) {
n = scanf("%d", &transpose);
gets(line);
}
/* loop, echoing input back transposed with multiple taps */
printf("Press C2 on the keyboard (2 octaves below middle C) to quit.\nWaiting for MIDI input...\n");
do {
err = Pm_Read(midi_in, buffer, 1);
if (err == 0) continue; /* no bytes read. */
/* print a hash mark for each event read. */
printf("#");
fflush(stdout);
status = Pm_MessageStatus(buffer[0].message);
data1 = Pm_MessageData1(buffer[0].message);
data2 = Pm_MessageData2(buffer[0].message);
statusprefix = status >> 4;
/* ignore messages other than key-down and key-up */
if ((statusprefix != 0x9) && (statusprefix != 0x8)) continue;
printf("\nReceived key message = %X %X %X, at time %ld\n", status, data1, data2, buffer[0].timestamp);
fflush(stdout);
/* immediately send the echoes to PortMIDI */
for (i = 1; i < NUM_ECHOES; i++) {
buffer[i].message = Pm_Message(status, data1 + transpose, data2 >> i);
buffer[i].timestamp = buffer[0].timestamp + (i * delay);
}
Pm_Write(midi_out, buffer, NUM_ECHOES);
} while (data1 != 36); /* quit when C2 is pressed */
printf("Key C2 pressed. Exiting...\n");
fflush(stdout);
/* Give the echoes time to finish before quitting. */
sleep(((NUM_ECHOES * delay) / 1000) + 1);
Pm_Close(midi_in);
Pm_Close(midi_out);
printf("Done.\n");
return 0;
}
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