1
0
Fork 0
mirror of https://github.com/ninjamuffin99/Funkin.git synced 2024-12-25 14:46:43 +00:00
Funkin/source/funkin/audio/visualize/VisShit.hx
2024-07-29 17:26:49 -04:00

143 lines
3.7 KiB
Haxe

package funkin.audio.visualize;
import flixel.math.FlxMath;
import flixel.sound.FlxSound;
import funkin.audio.visualize.dsp.FFT;
import lime.utils.Int16Array;
import funkin.util.MathUtil;
using Lambda;
class VisShit
{
public var snd:FlxSound;
public var setBuffer:Bool = false;
public var audioData:Int16Array;
public var sampleRate:Int = 44100; // default, ez?
public var numSamples:Int = 0;
public function new(snd:FlxSound)
{
this.snd = snd;
}
public function funnyFFT(samples:Array<Float>, ?skipped:Int = 1):Array<Array<Float>>
{
// nab multiple samples at once in while / for loops?
var fs:Float = 44100 / skipped; // sample rate shit?
final fftN = 1024;
final halfN = Std.int(fftN / 2);
final overlap = 0.5;
final hop = Std.int(fftN * (1 - overlap));
// window function to compensate for overlapping
final a0 = 0.5; // => Hann(ing) window
final window = (n:Int) -> a0 - (1 - a0) * Math.cos(2 * Math.PI * n / fftN);
// NOTE TO SELF FOR WHEN I WAKE UP
// helpers, note that spectrum indexes suppose non-negative frequencies
final binSize = fs / fftN;
final indexToFreq = function(k:Int) {
var powShit:Float = FlxMath.remapToRange(k, 0, halfN, 0, MathUtil.logBase(10, halfN)); // 4.3 is almost the log of 20Khz or so. Close enuf lol
return 1.0 * (Math.pow(10, powShit)); // we need the `1.0` to avoid overflows
};
// "melodic" band-pass filter
final minFreq = 20.70;
final maxFreq = 4000.01;
final melodicBandPass = function(k:Int, s:Float) {
final freq = indexToFreq(k);
final filter = freq > minFreq - binSize && freq < maxFreq + binSize ? 1 : 0;
return s;
};
var freqOutput:Array<Array<Float>> = [];
var c = 0; // index where each chunk begins
var indexOfArray:Int = 0;
while (c < samples.length)
{
// take a chunk (zero-padded if needed) and apply the window
final chunk = [
for (n in 0...fftN)
(c + n < samples.length ? samples[c + n] : 0.0) * window(n)
];
// compute positive spectrum with sampling correction and BP filter
final freqs = FFT.rfft(chunk).map(z -> z.scale(1 / fftN).magnitude).mapi(melodicBandPass);
freqOutput.push([]);
// find spectral peaks and their instantaneous frequencies
for (k => s in freqs)
{
final time = c / fs;
final freq = indexToFreq(k);
final power = s * s;
if (FlxG.keys.justPressed.I)
{
trace(k);
haxe.Log.trace('${time};${freq};${power}', null);
}
if (freq < maxFreq) freqOutput[indexOfArray].push(power);
//
}
indexOfArray++;
// move to next (overlapping) chunk
c += hop;
}
if (FlxG.keys.justPressed.C) trace(freqOutput.length);
return freqOutput;
}
public static function getCurAud(aud:Int16Array, index:Int):CurAudioInfo
{
var left = aud[index] / 32767;
var right = aud[index + 2] / 32767;
var balanced = (left + right) / 2;
var funny:CurAudioInfo = {left: left, right: right, balanced: balanced};
return funny;
}
public function checkAndSetBuffer()
{
if (snd != null && snd.playing)
{
if (!setBuffer)
{
// Math.pow3
@:privateAccess
var buf = snd._channel.__audioSource.buffer;
// @:privateAccess
audioData = cast buf.data; // jank and hacky lol! kinda busted on HTML5 also!!
sampleRate = buf.sampleRate;
trace('got audio buffer shit');
trace(sampleRate);
trace(buf.bitsPerSample);
setBuffer = true;
numSamples = Std.int(audioData.length / 2);
}
}
}
}
typedef CurAudioInfo =
{
var left:Float;
var right:Float;
var balanced:Float;
}