onPreviewFrame不会改变数据

这是我第一次在Android上编程，更多的我不是那么熟悉java的programmation。我试图通过互联网找到我的问题的答案，但没有找到任何解决方案。我希望你们中的一个能够帮助我。我想要做的是实时应用一些图像处理到摄像机并显示它。这就是为什么我使用onPreviewFrame函数在显示结果之前进行一些图像处理的原因。请告诉我，如果这不是最好的方法。我的问题是，当我尝试修改数据数组时，屏幕上没有任何更改。从我看到的调试器中调用该函数。所有这些都是用2.1 API完成的。onPreviewFrame不会改变数据

有人知道为什么吗？我该如何解决这个问题？

帮助，这里是我的代码：

import android.app.Activity; 
import android.content.Context; 
import android.hardware.Camera; 
import android.os.Bundle; 
import android.view.SurfaceHolder; 
import android.view.SurfaceView; 
import android.view.Window; 
import java.io.IOException; 

// ---------------------------------------------------------------------- 

public class CameraPreview extends Activity {  
    private Preview mPreview; 

    @Override 
    protected void onCreate(Bundle savedInstanceState) { 
     super.onCreate(savedInstanceState); 

     // Hide the window title. 
     requestWindowFeature(Window.FEATURE_NO_TITLE); 

     // Create our Preview view and set it as the content of our activity. 
     mPreview = new Preview(this); 
     setContentView(mPreview); 
    } 

} 

// ---------------------------------------------------------------------- 

class Preview extends SurfaceView implements SurfaceHolder.Callback, Camera.PreviewCallback { 
    SurfaceHolder mHolder; 
    Camera mCamera; 

    Preview(Context context) { 
     super(context); 

     // Install a SurfaceHolder.Callback so we get notified when the 
     // underlying surface is created and destroyed. 
     mHolder = getHolder(); 
     mHolder.addCallback(this); 
     mHolder.setType(SurfaceHolder.SURFACE_TYPE_PUSH_BUFFERS); 
    } 

    public void surfaceCreated(SurfaceHolder holder) { 
     // The Surface has been created, acquire the camera and tell it where 
     // to draw. 

     mCamera = Camera.open(); 
     try { 
      mCamera.setPreviewDisplay(holder);  
      mCamera.setPreviewCallback(this); 

     } catch (IOException e) { 
      // TODO Auto-generated catch block 
      e.printStackTrace(); 
     } 


    } 


    public void onPreviewFrame(byte[] data, Camera camera) { 
     if (data != null) { 
      for(int i=0;i<data.length;i++){ 
       data[i] = 0; 
      } 
     } 

    } 


    public void surfaceDestroyed(SurfaceHolder holder) { 
     // Surface will be destroyed when we return, so stop the preview. 
     // Because the CameraDevice object is not a shared resource, it's very 
     // important to release it when the activity is paused. 
     mCamera.stopPreview(); 
     mCamera.release(); 
     mCamera = null; 
    } 

    public void surfaceChanged(SurfaceHolder holder, int format, int w, int h) { 
     // Now that the size is known, set up the camera parameters and begin 
     // the preview. 
     Camera.Parameters parameters = mCamera.getParameters(); 
     parameters.setPreviewSize(w, h); 
     mCamera.setParameters(parameters); 
     mCamera.startPreview(); 
    } 

}

谢谢你的帮助，摩根科米尔

来源

2011-04-28 MorganCormier