新手菜鸟视频捕捉实验遇到的疑问

[fengenjoy]

新人刚开始研究processing，之前是graphic design背景，没有怎么接触过，现在以自学为主，书本结合学习他人代码开始。
我现在想完成一个小的实验，目的是想用摄像头捕捉动态，然后根据捕捉动态的坐标移动，获取该移动位置的颜色参数，用这些参数产生频率，进而发出声音。
我在openprocessing上面看到一个sketch，是类似的概念，但是他只是读取静态图片的颜色数据，捕捉方式是鼠标移动。我用了他的这个原理，加入了摄像头捕捉，数据都可以获得，并且print出是数据都在变化，但是有minim error报错，求大侠指点。

报错：=== Minim Error ===
=== Likely buffer underrun in AudioOutput.

下面这个是我参考的code：

程序代码

import ddf.minim.*;
import ddf.minim.signals.*;
 
Minim minim;
AudioOutput out;
SineWave sine;
PImage a;
int[] aPixels;
int direction = 1;
boolean onetime = true;
float signal;
 
void setup()
{
  size(800, 535);
  aPixels = new int[width*height];
  noFill();
  stroke(255);
  frameRate(50);
  a = loadImage("test4.jpg");
  for(int i=0; i<width*height; i++) {
    aPixels[i] = a.pixels[i];
  }
   
   
  minim = new Minim(this);
  // get a line out from Minim, default bufferSize is 1024, default sample rate is 44100, bit depth is 16
  out = minim.getLineOut(Minim.STEREO);
  // create a sine wave Oscillator, set to 440 Hz, at 0.5 amplitude, sample rate from line out
  sine = new SineWave(440, 0.5, out.sampleRate());
  // set the portamento speed on the oscillator to 200 milliseconds
  sine.portamento(10);
  // add the oscillator to the line out
  out.addSignal(sine);
}
 
void draw()
{
  if (signal > width*height-1 ||
      signal < 0) {
    direction = direction * -1;
  }
 
  if(mousePressed) {
    if(mouseY > height-1) {
      mouseY = height-1;
    }
    if(mouseY < 0) {
      mouseY = 0;
    }
    signal = mouseY*width+mouseX;
  } else {
    signal += (0.33*direction); 
  }
   
   
    loadPixels();
    for (int i=0; i<width*height; i++) {
      pixels[i] = aPixels[i]; 
    }
    updatePixels();
    rect(signal%width-5, int(signal/width)-5, 10, 10);
    point(signal%width, int(signal/width));
    
  // with portamento on the frequency will change smoothly
  float freq = map(hue(aPixels[int(signal)]), 0, 255, 261.63, 523.25);
  //aPixels[int(signal)];
  sine.setFreq(freq);
  // pan always changes smoothly to avoid crackles getting into the signal
  // note that we could call setPan on out, instead of on sine
  // this would sound the same, but the waveforms in out would not reflect the panning
  float pan = map(pixels[int(signal)], 0, width, -1, 1);
  sine.setPan(pan);
   
  print ("\n Brillo= " + brightness (aPixels[int(signal)]) + "   hue= " + hue (aPixels[int(signal)]) + "  Freq= " + freq);
}

下面这个是我结合和修改的code（比较乱，我直接复制来了 ：）：

程序代码

import processing.video.*;
 import ddf.minim.*;
import ddf.minim.signals.*;

Capture video;
 
PImage prevFrame;
 
float threshold = 150;

Minim minim;
AudioOutput out;
SineWave sine;
PImage a;
float signal;

int[] aPixels;

int Mx = 0;
int My = 0;
int ave = 0;
 
int ballX = width/2;
int ballY = height/2;
int rsp = 25;
 
void setup() 
{
  size(800, 535);
 // aPixels = new int[width*height];
  //noFill();
  //stroke(255);
  //frameRate(50);
  //a = loadImage("test4.jpg");
  aPixels = new int[width*height];
  video = new Capture(this, width, height, 30);
  
  prevFrame = createImage(video.width,video.height,RGB);
  for(int i=0; i<width*height; i++) {
    a = prevFrame;
    aPixels[i] = a.pixels[i];
  }

}
 // print ("chech point 3");
  
void draw() {
   
 
  if (video.available()) {
     
    prevFrame.copy(video,0,0,video.width,video.height,0,0,video.width,video.height);
    prevFrame.updatePixels();
    video.read();
     for(int i=0; i<width*height; i++) {
    a = prevFrame;
    aPixels[i] = a.pixels[i];
  }

  }
   
  loadPixels();
  video.loadPixels();
  prevFrame.loadPixels();
   
  Mx = 0;
  My = 0;
  ave = 0;
   
  
  for (int x = 0; x < video.width; x ++ ) {
    for (int y = 0; y < video.height; y ++ ) {
       
      int loc = x + y*video.width;           
      color current = video.pixels[loc];     
      color previous = prevFrame.pixels[loc];
       
      
      float r1 = red(current); float g1 = green(current); float b1 = blue(current);
      float r2 = red(previous); float g2 = green(previous); float b2 = blue(previous);
      float diff = dist(r1,g1,b1,r2,g2,b2);
       
       
      if (diff > threshold) {
        pixels[loc] = video.pixels[loc];
        Mx += x;
        My += y;
        ave++;
      } else {
         
        pixels[loc] = video.pixels[loc];
      }
    }
  }
  
   //print ("chech point 2");
   
  fill(255);
  rect(0,0, width, height);
  if(ave != 0){
    Mx = Mx/ave;
    My = My/ave;
  }
  if (Mx > ballX + rsp/2 && Mx > 50){
    ballX+= rsp;
  }else if (Mx < ballX - rsp/2 && Mx > 50){
    ballX-= rsp;
  }
  if (My > ballY + rsp/2 && My > 50){
    ballY+= rsp;
  }else if (My < ballY - rsp/2 && My > 50){
    ballY-= rsp;
  }
     
   // updatePixels();
    //print ("chech point 1");
    
     minim = new Minim(this);
  // get a line out from Minim, default bufferSize is 1024, default sample rate is 44100, bit depth is 16
  out = minim.getLineOut(Minim.STEREO);
  // create a sine wave Oscillator, set to 440 Hz, at 0.5 amplitude, sample rate from line out
  sine = new SineWave(440, 0.5, out.sampleRate());
  // set the portamento speed on the oscillator to 200 milliseconds
  sine.portamento(10);
  // add the oscillator to the line out
  out.addSignal(sine);
  
  signal = ballY*width+ballX;
 
  
  float freq = map(hue(aPixels[int(signal)]), 0, 255, 261.63, 987.77)/2 ;
  
  //aPixels[int(signal)];
  sine.setFreq(freq);
  // pan always changes smoothly to avoid crackles getting into the signal
  // note that we could call setPan on out, instead of on sine
  // this would sound the same, but the waveforms in out would not reflect the panning
  float pan = map(pixels[int(signal)], 0, width, -1, 1);
  sine.setPan(pan);
  
  print ("\n Brillo= " + brightness (aPixels[int(signal)]) + "   hue= " + hue (aPixels[int(signal)]) + "  Freq= " + freq);
  //print ("ballX = "+ ballX  +  " ballY =" + ballY);
  //print("signal =" + signal);
  //print("freq =" + freq);
  
    updatePixels();
    noFill();
    //noStroke();
    //fill(0,0,0);
    ellipse(ballX, ballY, 25, 25);
     
   
}

[Contra]

请这样引用代码，编辑工具里的“#”

程序代码

import ddf.minim.*;
import ddf.minim.signals.*;
 
Minim minim;
AudioOutput out;
SineWave sine;
PImage a;

[vinjn]

如果报错，请帖错误信息
大于10行的代码我是肯定不会看的
请尊重帮你解答问题的人

[fengenjoy]

如果报错，请帖错误信息
大于10行的代码我是肯定不会看的
请尊重帮你解答问题的人

谢谢，是报错，将下面的错误信息贴上来吗？

[fengenjoy]

请这样引用代码，编辑工具里的“#”

程序代码

import ddf.minim.*;
import ddf.minim.signals.*;
 
Minim minim;
AudioOutput out;
SineWave sine;
PImage a;

哦，不好意思，之前不了解。

[fengenjoy]

如果报错，请帖错误信息
大于10行的代码我是肯定不会看的
请尊重帮你解答问题的人

不好意思，我把报错贴上来啦，谢谢