forked from: Simple spectrum analyzer (SiON FFT module + FP10.1 microphone)

/**
 * Copyright ohisama ( http://wonderfl.net/user/ohisama )
 * MIT License ( http://www.opensource.org/licenses/mit-license.php )
 * Downloaded from: http://wonderfl.net/c/3eKd
 */

// forked from keim_at_Si's Simple spectrum analyzer (SiON FFT module + FP10.1 microphone)
// forked from keno42's FP10.1用 マイク録音&再生
// SiON FFT module で 声紋解析 (Hamming窓＋時間分解能11ms)
package 
{
    import flash.display.*;
    import flash.events.*;
    import flash.media.*;
    import flash.text.*;
    import flash.utils.ByteArray;
    import org.si.utils.FFT;
    import frocessing.color.ColorLerp;
    import com.bit101.components.*;
    public class main extends Sprite 
    {
        private var voicePrint : BitmapData = new BitmapData(465, 256, false, 0);
        private var mic : Microphone, scaler : HSlider;
        public function main() 
        {
            _initFFT();
            with (addChild(new Bitmap(voicePrint)))
            { 
                y = 100; 
            }
            (scaler = new HSlider(this, 100, 370, _onScalerChanged)).setSize(264, 20);
            scaler.value = 25;
            mic = Microphone.getMicrophone();
            mic.rate = 44;
            mic.setSilenceLevel(0);
            mic.setLoopBack();
            mic.addEventListener("sampleData", _in);
        }        
        private function _onScalerChanged(e : Event) : void 
        { 
            scale = scaler.value;
        }        
        private function _in(e : SampleDataEvent) : void 
        {
            for (e.data.position = 0; e.data.bytesAvailable > 0;) 
            {
                _execFFT(e.data);
                _updateImage();
            }
        }        
        private function _updateImage() : void 
        {
            voicePrint.scroll(-4, 0);
            for (var i : int = 0; i < 256; i++) 
            {
                voicePrint.setPixel(461, 255 - i, grad[frm[3][i]]);
                voicePrint.setPixel(462, 255 - i, grad[frm[2][i]]);
                voicePrint.setPixel(463, 255 - i, grad[frm[1][i]]);
                voicePrint.setPixel(464, 255 - i, grad[frm[0][i]]);
            }
        }
        private var src : Vector.<Vector.<Number>> = new Vector.<Vector.<Number>>(4);
        private var dst : Vector.<Vector.<Number>> = new Vector.<Vector.<Number>>(4);
        private var amp : Vector.<Vector.<Number>> = new Vector.<Vector.<Number>>(4);
        private var frm : Vector.<Vector.<int>> = new Vector.<Vector.<int>>(4);
        private var hamm : Vector.<Number> = new Vector.<Number>(2048);
        private var fft : FFT = new FFT(2048);
        private var grad : Array, scale : Number;
        private function _initFFT() : void 
        {
            var i : int;
            for (i = 0; i < 4; i++) 
            {
                src[i] = new Vector.<Number>(2048);
                dst[i] = new Vector.<Number>(2048);
                amp[i] = new Vector.<Number>(1024);
                frm[i] = new Vector.<int>(256);
            }
            for (i = 0; i < 2048; i++) 
            {              
                hamm[i] = 0.54 - Math.cos(i * 0.00306796) * 0.46;
            }
            ColorLerp.mode = "hsv";
            grad = ColorLerp.gradient(0x000040, 0xffff00, 256);
            scale = 25;
        } 
        private function _execFFT(data : ByteArray) : void 
        {
            var index : int, i : int, j : int, n : Number, 
                f : Vector.<int>, a : Vector.<Number>,
                s0 : Vector.<Number> = src[0],
                s1 : Vector.<Number> = src[1],
                s2 : Vector.<Number> = src[2],
                s3 : Vector.<Number> = src[3];
            for (index = 3; index >= 0; --index) 
            {
                for (i = 0; i < 512; i++) 
                {
                    n = data.readFloat();
                    j = i;     
                    s0[j] = n * hamm[j];
                    j += 512;  
                    s1[j] = n * hamm[j];
                    j += 512;  
                    s2[j] = n * hamm[j];
                    j += 512;  
                    s3[j] = n * hamm[j];
                }
                a = amp[index];
                f = frm[index];
                fft.setData(s3).calcDCT().getMagnitude(a)
                for (i = 0; i < 256; i++) 
                {
                    // from 86Hz to 5.6kHz
                    n = Math.log(a[i + 4] * scale);
                    f[i] = int(((n < 0) ? 0 : (n > 1) ? 1 : n) * 255);
                }
                s3 = s2;
                s2 = s1;
                s1 = s0;
                s0 = src[index];
            }
        }
    }   
}