Sound Demo 3

Aus ProgrammingWiki

javax.sound.sampled.AudioFormat audioFormat; javax.sound.sampled.AudioInputStream audioInputStream; javax.sound.sampled.SourceDataLine sourceDataLine; float sampleRate = 16000.0F; int sampleSizeInBits = 16; int channels = 1; boolean signed = true; boolean bigEndian = true; audioData = new byte[16000*16]; void fillBuffer(double startat,double freq) { java.nio.ByteBuffer byteBuffer; java.nio.ShortBuffer shortBuffer; int byteLength; byteBuffer = java.nio.ByteBuffer.wrap(audioData); shortBuffer = byteBuffer.asShortBuffer(); byteLength = audioData.length; channels = 1;//Java allows 1 or 2 int bytesPerSamp = 2; int sampLength = byteLength / bytesPerSamp; for (int cnt = 0; cnt < sampLength; cnt++) { double time = cnt / sampleRate; double sinValue = playFunction(startat/2+time,freq); shortBuffer.put((short)(16000 * sinValue)); } } void draw(double dauer, double start,double freq){ dauer = dauer * 2; canvas.clear(); double oldy = 100; canvas.setColor(200,200,200); canvas.line(0,100,600,100); canvas.setColor(0,0,0); for(int x=0; x< 600; x++) { double newy = 100+100*playFunction(start/2+((double)dauer/2/600*x),freq); if(start/2+(double)dauer/2/600*x == 0){ canvas.setColor(200,200,200); canvas.line(x,0,x,200); canvas.setColor(0,0,0); } canvas.line((x-1),(int)(oldy),x,(int)(newy)); oldy = newy; } } void play(double dauer, double startat,double freq){ dauer = dauer * 2; audioData = new byte[16000*dauer]; try{ fillBuffer(startat,freq); InputStream byteArrayInputStream = new ByteArrayInputStream(audioData); audioFormat = new javax.sound.sampled.AudioFormat(sampleRate, sampleSizeInBits, channels, signed, bigEndian); audioInputStream = new javax.sound.sampled.AudioInputStream(byteArrayInputStream, audioFormat, audioData.length / audioFormat.getFrameSize()); javax.sound.sampled.DataLine.Info dataLineInfo = new javax.sound.sampled.DataLine.Info(javax.sound.sampled.SourceDataLine.class, audioFormat); sourceDataLine = (javax.sound.sampled.SourceDataLine)javax.sound.sampled.AudioSystem.getLine(dataLineInfo); sourceDataLine.open(audioFormat); sourceDataLine.start(); playBuffer = new byte[16384]; int cnt; while ((cnt = audioInputStream.read(playBuffer, 0,playBuffer.length))!= -1) if (cnt > 0) sourceDataLine.write(playBuffer, 0, cnt); sourceDataLine.drain(); sourceDataLine.stop(); sourceDataLine.close(); } catch (Exception e){e.printStackTrace();System.exit(0);} }

Mit diesem Beispiel kann man Funktionen hörbar machen. In diesem Beispiel werden 3 Sinuskurven zu einem Ton zusammengefügt. Gleichzeitig wird mit gain ein Abklingen des Tones simuliert.

// erzeugt eine Art Glockenschlag double playFunction(double x, double freq){ double gain = 1.0-Math.log(x+1)/1.8; if(gain < 0) gain = 0; double sinValue = (Math.sin(2*Math.PI*freq*x) + Math.sin(2*Math.PI*(freq/1.8)*x) + Math.sin(2*Math.PI*(freq/1.5)*x))/3.0; return (sinValue)*gain; } draw(5,0,500.0); // 5 Sekunden diese Funktion spielen und mit x=0 beginnen play(5,0,500.0); // Frequenz von 500 Herz

ausführen

void fillToneBuffer(byte[] a, double startat,double freq) { java.nio.ByteBuffer byteBuffer; java.nio.ShortBuffer shortBuffer; int byteLength; byteBuffer = java.nio.ByteBuffer.wrap(a); shortBuffer = byteBuffer.asShortBuffer(); byteLength = a.length; channels = 1;//Java allows 1 or 2 int bytesPerSamp = 2; int sampLength = byteLength / bytesPerSamp; for (int cnt = 0; cnt < sampLength; cnt++) { double time = cnt / sampleRate; double sinValue = ToneFunction(startat/2+time,freq); shortBuffer.put((short)(16000 * sinValue)); } } Vector tones = new Vector(); void fillTones() { tones = new Vector(); for(int i=0; i < 8; i++){ tempBuffer = new byte[16000*1]; // 0.5 sekunden double f = 0; if(i == 0) f = 264.0; if(i == 1) f = 297.0; if(i == 2) f = 330.0; if(i == 3) f = 352.0; if(i == 4) f = 396.0; if(i == 5) f = 440.0; if(i == 6) f = 495.0; if(i == 7) f = 528.0; fillToneBuffer(tempBuffer,0,f); tones.add(tempBuffer); } } void playTone(int t) { try{ audioData = (byte[]) tones.get(t); InputStream byteArrayInputStream = new ByteArrayInputStream(audioData); audioFormat = new javax.sound.sampled.AudioFormat(sampleRate, sampleSizeInBits, channels, signed, bigEndian); audioInputStream = new javax.sound.sampled.AudioInputStream(byteArrayInputStream, audioFormat, audioData.length / audioFormat.getFrameSize()); javax.sound.sampled.DataLine.Info dataLineInfo = new javax.sound.sampled.DataLine.Info(javax.sound.sampled.SourceDataLine.class, audioFormat); sourceDataLine = (javax.sound.sampled.SourceDataLine)javax.sound.sampled.AudioSystem.getLine(dataLineInfo); sourceDataLine.open(audioFormat); sourceDataLine.start(); playBuffer = new byte[16384]; int cnt; while ((cnt = audioInputStream.read(playBuffer, 0,playBuffer.length))!= -1) if (cnt > 0) sourceDataLine.write(playBuffer, 0, cnt); sourceDataLine.drain(); sourceDataLine.stop(); sourceDataLine.close(); } catch (Exception e){e.printStackTrace();System.exit(0);} } void playTones(String s) { s = s.toLowerCase(); for(int i=0; i < s.length(); i++){ if(s.charAt(i) == 'c') playTone(0); if(s.charAt(i) == 'd') playTone(1); if(s.charAt(i) == 'e') playTone(2); if(s.charAt(i) == 'f') playTone(3); if(s.charAt(i) == 'g') playTone(4); if(s.charAt(i) == 'a') playTone(5); if(s.charAt(i) == 'h') playTone(6); } }

In diesem Beispiel werden zunächst die Grundtöne C,D,E,F,G,A und H in einem Vector durch die Funktion fillTones() vor berechnet. Anschließend wird eine Tonfolge ausgegeben. Sie können diese Zeichenkette und die ToneFunction beliebig anpassen.

double ToneFunction(double x, double freq){ double gain = 1.0-Math.log(x+1)/0.6; if(gain < 0) gain = 0; double sinValue = (Math.sin(2*Math.PI*freq*x) + Math.sin(2*Math.PI*(freq/1.8)*x) + Math.sin(2*Math.PI*(freq/1.5)*x))/3.0; return (sinValue)*gain; } fillTones(); playTones("E E F G G F E D C C D E E D D"); // spielt eine Tonfolge ab.

ausführen