jwebcamplayer.java

嵌入式linux下的摄像头控制程序. 在arm-linux3.4.1下测试通过.

                                    //r = in.read(buffer, n, HDLREN + siz - n);
                                    r = in.read(buffer, n, buffer.length - n);
                                }   
                                catch(Exception e)
                                {
                                    e.printStackTrace();
                                }

                                n += r;

                                if (DEBUGGING)
                                    System.out.println(" chunk read, size="+Integer.toString(r)+" total="+Integer.toString(n));

                                /*if (r<=0) 
                                {
                                    n = r;
                                    break;
                                }*/
                            }
                            while(n<(siz+HDRLEN));
                        }

                        if (DEBUGGING)
                            System.out.println("jpeg read, size="+Integer.toString(n));
                    }
                 
                    byte [] buffer2 = new byte [n];
                    
                    for(int i=0; i<n; i++)
                        buffer2[i] = buffer[i+HDRLEN];

										
										try{
											BufferedImage image = ImageIO.read(new ByteArrayInputStream(buffer2));																					
											if(do_overlay) {
												Graphics2D g = image.createGraphics();
												g.drawImage(image, 0, 0, null);
												g.setComposite(AlphaComposite.getInstance(AlphaComposite.SRC_OVER, 0.4f));
												g.drawImage(overlay, 0, 0, null);
												g.dispose();
											}
																						
											ImageIcon ii = new ImageIcon(image);

//                    ImageIcon ii = new ImageIcon(Toolkit.getDefaultToolkit().createImage(buffer2));
	
											if (ii.getIconHeight()<=1 || ii.getIconWidth()<=1)
											{
													if (DEBUGGING)
															System.out.println("--invalid image got");
													continue;
											}
											else 
											{    
													if (DEBUGGING)
															System.out.println("--VALID image got");
											}
	
											m_label.setIcon(ii);
										}	
										catch (IOException e) {}
                }//while
                
                try {
                  connection.close();
                      // (Alternatively, you might depend on the server
                      //  to close the connection.)
                }
                catch (IOException e) {
                }

                m_label.setIcon(null);
                m_label.setText("JWebcamPlayer - Connection closed");
                
                if (DEBUGGING)
                {
                    if (m_stop)
                        System.out.println("** worker ending (m_stop==true)");
                    else    
                        System.out.println("** worker ending (m_stop==false)");
                }                          
                        
                m_stop = true;
                
                return null;
            }
        };
       
        m_worker.start();  //required for SwingWorker 3
    }
    
    public void stop()
    {
        if (DEBUGGING)
            System.out.println("--stopping worker (applet stop)");
        
        m_stop = true;
    }
 
    // This method returns true if the specified image has transparent pixels
    public static boolean hasAlpha(Image image) {
			// If buffered image, the color model is readily available
      if (image instanceof BufferedImage) {
      	BufferedImage bimage = (BufferedImage)image;
        return bimage.getColorModel().hasAlpha();
      }
    
      // Use a pixel grabber to retrieve the image's color model;
      // grabbing a single pixel is usually sufficient
      PixelGrabber pg = new PixelGrabber(image, 0, 0, 1, 1, false);
      try {
      	 pg.grabPixels();
      } catch (InterruptedException e) { }
    
      // Get the image's color model
      ColorModel cm = pg.getColorModel();
      return cm.hasAlpha();
    }

    // This method returns a buffered image with the contents of an image
    public static BufferedImage toBufferedImage(Image image) {
        if (image instanceof BufferedImage) {
            return (BufferedImage)image;
        }
    
        // This code ensures that all the pixels in the image are loaded
        image = new ImageIcon(image).getImage();
    
        // Determine if the image has transparent pixels; for this method's
        // implementation, see e661 Determining If an Image Has Transparent Pixels
        boolean hasAlpha = hasAlpha(image);
    
        // Create a buffered image with a format that's compatible with the screen
        BufferedImage bimage = null;
        GraphicsEnvironment ge = GraphicsEnvironment.getLocalGraphicsEnvironment();
        try {
            // Determine the type of transparency of the new buffered image
            int transparency = Transparency.OPAQUE;
            if (hasAlpha) {
                transparency = Transparency.BITMASK;
            }
    
            // Create the buffered image
            GraphicsDevice gs = ge.getDefaultScreenDevice();
            GraphicsConfiguration gc = gs.getDefaultConfiguration();
            bimage = gc.createCompatibleImage(
                image.getWidth(null), image.getHeight(null), transparency);
        } catch (HeadlessException e) {
            // The system does not have a screen
        }
    
        if (bimage == null) {
            // Create a buffered image using the default color model
            int type = BufferedImage.TYPE_INT_RGB;
            if (hasAlpha) {
                type = BufferedImage.TYPE_INT_ARGB;
            }
            bimage = new BufferedImage(image.getWidth(null), image.getHeight(null), type);
        }
    
        // Copy image to buffered image
        Graphics g = bimage.createGraphics();
    
        // Paint the image onto the buffered image
        g.drawImage(image, 0, 0, null);
        g.dispose();
    
        return bimage;
    }
		
   	public void mouseClicked(MouseEvent evt) {
		
      int x = evt.getX();  // Location where user clicked.
      int y = evt.getY();
			
			System.out.println("x="+Integer.toString(x)+" y="+Integer.toString(y));
			
			if(do_overlay) {
				//base check
				if(x>0 && x<42 && y>0 && y<42) {
					if(y>2 && y<18) {								//contrast
						
						if(x>0 && x<10) {								//decrement
							System.out.println("c -");
							contrast_down = true;
						}
						else if(x > 30 && x < 40) {			//increment
							System.out.println("c +");
							contrast_up = true;
						}
					} else if(y > 22 && y < 40) {		//brightness
						
						if(x>0 && x<10) {								//decrement
							System.out.println("b -");
							bright_down = true;
						}
						else if(x > 30 && x < 40) {			//increment
							System.out.println("b +");
							bright_up = true;
						}
					}		
				} else {
					do_overlay=false;
				}
			} else {
			 do_overlay=true;
			}
		
		
		}

		
		public void mousePressed(MouseEvent evt) { }
		public void mouseReleased(MouseEvent evt) { }
		public void mouseDragged(MouseEvent evt) { }
   	public void mouseMoved(MouseEvent evt) { }
   	public void mouseEntered(MouseEvent evt) { }
   	public void mouseExited(MouseEvent evt) { }

		   
    private final int HDRLEN = 50;
    private final int SZOFS = 29;
		private BufferedImage overlay = null;
		private boolean do_overlay = false;
    private JLabel m_label = null;
    private String m_strServer = null;
    private String m_strPort = null;
    private String m_strColor = null;
    private boolean m_stop = false;
    private SwingWorker m_worker = null;
		private boolean bright_up = false;
		private boolean bright_down = false;
		private boolean contrast_up = false;
		private boolean contrast_down = false;
		

}