Musical scale: Difference between revisions

=={{header|Sparkling}}==

The following Sparkling program generates a WAVE audio file named "notes.wav" that can be played in order to achieve the required effect:

<lang Sparkling>

var sampleRate = 44100.0;

var duration = 8.0;

var dataLength = round(sampleRate * duration); // 1 second of data

var dataLength_b0 = dataLength >> 0 & 0xff;

var dataLength_b1 = dataLength >> 8 & 0xff;

var dataLength_b2 = dataLength >> 16 & 0xff;

var dataLength_b3 = dataLength >> 24 & 0xff;

const adjustedHdrSize = 36;

var len = dataLength - adjustedHdrSize;

var len_b0 = len >> 0 & 0xff;

var len_b1 = len >> 8 & 0xff;

var len_b2 = len >> 16 & 0xff;

var len_b3 = len >> 24 & 0xff;

// WAV header

var wavhdr = "RIFF";

wavhdr ..= fmtstr("%c%c%c%c", len_b0, len_b1, len_b2, len_b3);

wavhdr ..= "WAVE";

wavhdr ..= "fmt ";

wavhdr ..= "\x10\x00\x00\x00";

wavhdr ..= "\x01\x00";

wavhdr ..= "\x01\x00";

wavhdr ..= "\x44\xac\x00\x00";

wavhdr ..= "\x44\xac\x00\x00";

wavhdr ..= "\x01\x00";

wavhdr ..= "\x08\x00";

wavhdr ..= "data";

wavhdr ..= fmtstr("%c%c%c%c", dataLength_b0, dataLength_b1, dataLength_b2, dataLength_b3);

// write wav header

var f = fopen("notes.wav", "w");

fwrite(f, wavhdr);

// compute and write actual data

var frequs = { 261.6, 293.6, 329.6, 349.2, 392.0, 440.0, 493.9, 523.3 };

for var j = 0; j < duration; j++ {

var frequ = frequs[j];

var omega = 2 * M_PI * frequ;

for var i = 0; i < dataLength / 8; i++ {

var y = 32 * sin(omega * i / sampleRate);

var byte = fmtstr("%c", round(y));

fwrite(f, byte);

}

}

fclose(f);</lang>