mirror of
https://github.com/cookiengineer/audacity
synced 2025-05-05 14:18:53 +02:00
130 lines
2.7 KiB
C++
130 lines
2.7 KiB
C++
/******************************************/
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/*
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play_saw.c
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by Gary P. Scavone, 2001
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Play sawtooth waveforms of distinct frequency.
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Takes number of channels and sample rate as
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input arguments. Uses blocking functionality.
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*/
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/******************************************/
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#include "RtAudio.h"
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#include <iostream>
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/*
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typedef signed long MY_TYPE;
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#define FORMAT RTAUDIO_SINT24
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#define SCALE 2147483647.0
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typedef char MY_TYPE;
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#define FORMAT RTAUDIO_SINT8
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#define SCALE 127.0
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*/
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typedef signed short MY_TYPE;
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#define FORMAT RTAUDIO_SINT16
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#define SCALE 32767.0
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/*
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typedef signed long MY_TYPE;
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#define FORMAT RTAUDIO_SINT32
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#define SCALE 2147483647.0
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typedef float MY_TYPE;
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#define FORMAT RTAUDIO_FLOAT32
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#define SCALE 1.0
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typedef double MY_TYPE;
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#define FORMAT RTAUDIO_FLOAT64
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#define SCALE 1.0
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*/
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#define BASE_RATE 0.005
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#define TIME 4.0
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void usage(void) {
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// Error function in case of incorrect command-line
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// argument specifications.
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std::cout << "\nuseage: play_saw N fs <device>\n";
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std::cout << " where N = number of channels,\n";
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std::cout << " fs = the sample rate,\n";
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std::cout << " and device = the device to use (default = 0).\n\n";
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exit(0);
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}
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int main(int argc, char *argv[])
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{
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int chans, fs, buffer_size, device = 0;
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long frames, counter = 0, i, j;
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MY_TYPE *buffer;
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RtAudio *audio;
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double *data = 0;
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// minimal command-line checking
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if (argc != 3 && argc != 4 ) usage();
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chans = (int) atoi(argv[1]);
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fs = (int) atoi(argv[2]);
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if ( argc == 4 )
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device = (int) atoi(argv[3]);
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// Open the realtime output device
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buffer_size = 512;
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try {
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audio = new RtAudio(device, chans, 0, 0,
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FORMAT, fs, &buffer_size, 4);
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}
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catch (RtError &error) {
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error.printMessage();
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exit(EXIT_FAILURE);
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}
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frames = (long) (fs * TIME);
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data = (double *) calloc(chans, sizeof(double));
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try {
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buffer = (MY_TYPE *) audio->getStreamBuffer();
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audio->startStream();
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}
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catch (RtError &error) {
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error.printMessage();
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goto cleanup;
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}
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std::cout << "\nPlaying for " << TIME << " seconds ... buffer size = " << buffer_size << "." << std::endl;
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while (counter < frames) {
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for (i=0; i<buffer_size; i++) {
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for (j=0; j<chans; j++) {
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buffer[i*chans+j] = (MY_TYPE) (data[j] * SCALE);
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data[j] += BASE_RATE * (j+1+(j*0.1));
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if (data[j] >= 1.0) data[j] -= 2.0;
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}
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}
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try {
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audio->tickStream();
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}
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catch (RtError &error) {
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error.printMessage();
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goto cleanup;
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}
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counter += buffer_size;
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}
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try {
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audio->stopStream();
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}
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catch (RtError &error) {
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error.printMessage();
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}
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cleanup:
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audio->closeStream();
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delete audio;
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if (data) free(data);
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return 0;
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}
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