smartdashboard/src/edu/wpi/first/smartdashboard/gui/elements/VideoStreamViewerExtension.java

   1 package edu.wpi.first.smartdashboard.gui.elements;
   2
   3 import edu.wpi.first.smartdashboard.gui.DashboardPrefs;
   4 import edu.wpi.first.smartdashboard.gui.StaticWidget;
   5 import edu.wpi.first.smartdashboard.properties.IntegerProperty;
   6 import edu.wpi.first.smartdashboard.properties.Property;
   7 import edu.wpi.first.smartdashboard.properties.StringProperty;
   8
   9 import java.awt.Color;
  10 import java.awt.Dimension;
  11 import java.awt.Graphics;
  12 import java.awt.Graphics2D;
  13 import java.awt.geom.AffineTransform;
  14 import java.awt.image.BufferedImage;
  15 import java.io.ByteArrayInputStream;
  16 import java.io.ByteArrayOutputStream;
  17 import java.io.InputStream;
  18 import java.net.URL;
  19 import java.net.URLConnection;
  20
  21 import javax.imageio.ImageIO;
  22
  23 /**
  24  *
  25  * @author Greg Granito
  26  */
  27 public class VideoStreamViewerExtension extends StaticWidget {
  28
  29     public static final String NAME = "Simple Camera Viewer";
  30
  31
  32     private static final int[] START_BYTES = new int[]{0xFF, 0xD8};
  33     private static final int[] END_BYTES = new int[]{0xFF, 0xD9};
  34
  35     private boolean ipChanged = true;
  36     private String ipString = null;
  37     private double rotateAngleRad = 0;
  38     private long lastFPSCheck = 0;
  39     private int lastFPS = 0;
  40     private int fpsCounter = 0;
  41     public class BGThread extends Thread {
  42
  43         boolean destroyed = false;
  44
  45         public BGThread() {
  46             super("Camera Viewer Background");
  47         }
  48
  49         long lastRepaint = 0;
  50         @Override
  51         public void run() {
  52             URLConnection connection = null;
  53             InputStream stream = null;
  54             ByteArrayOutputStream imageBuffer = new ByteArrayOutputStream();
  55             while (!destroyed) {
  56                 try{
  57                     System.out.println("Connecting to camera");
  58                     ipChanged = false;
  59                     URL url = new URL("http://"+ipString+"/mjpg/video.mjpg");
  60                     connection = url.openConnection();
  61                     connection.setReadTimeout(250);
  62                     stream = connection.getInputStream();
  63
  64                     while(!destroyed && !ipChanged){
  65                         while(System.currentTimeMillis()-lastRepaint<10){
  66                             stream.skip(stream.available());
  67                             Thread.sleep(1);
  68                         }
  69                         stream.skip(stream.available());
  70
  71                         imageBuffer.reset();
  72                         for(int i = 0; i<START_BYTES.length;){
  73                             int b = stream.read();
  74                             if(b==START_BYTES[i])
  75                                 i++;
  76                             else
  77                                 i = 0;
  78                         }
  79                         for(int i = 0; i<START_BYTES.length;++i)
  80                             imageBuffer.write(START_BYTES[i]);
  81
  82                         for(int i = 0; i<END_BYTES.length;){
  83                             int b = stream.read();
  84                             imageBuffer.write(b);
  85                             if(b==END_BYTES[i])
  86                                 i++;
  87                             else
  88                                 i = 0;
  89                         }
  90
  91                         fpsCounter++;
  92                         if(System.currentTimeMillis()-lastFPSCheck>500){
  93                             lastFPSCheck = System.currentTimeMillis();
  94                             lastFPS = fpsCounter*2;
  95                             fpsCounter = 0;
  96                         }
  97
  98                         lastRepaint = System.currentTimeMillis();
  99                         ByteArrayInputStream tmpStream = new ByteArrayInputStream(imageBuffer.toByteArray());
 100                         imageToDraw = ImageIO.read(tmpStream);
 101                         System.out.println(System.currentTimeMillis()-lastRepaint);
 102                         repaint();
 103                     }
 104
 105                 } catch(Exception e){
 106                     imageToDraw = null;
 107                     repaint();
 108                     e.printStackTrace();
 109                 }
 110
 111                 if(!ipChanged){
 112                     try {
 113                         Thread.sleep(500);
 114                     } catch (InterruptedException ex) {}
 115                 }
 116             }
 117
 118         }
 119
 120         @Override
 121         public void destroy() {
 122             destroyed = true;
 123         }
 124     }
 125     private BufferedImage imageToDraw;
 126     private BGThread bgThread = new BGThread();
 127     public final StringProperty ipProperty = new StringProperty(this, "Camera IP Address or mDNS name", "axis-camera.local");
 128     public final IntegerProperty rotateProperty = new IntegerProperty(this, "Degrees Rotation", 0);
 129
 130     @Override
 131     public void init() {
 132         setPreferredSize(new Dimension(100, 100));
 133         ipString = ipProperty.getSaveValue();
 134         rotateAngleRad = Math.toRadians(rotateProperty.getValue());
 135         bgThread.start();
 136         revalidate();
 137         repaint();
 138     }
 139
 140     @Override
 141     public void propertyChanged(Property property) {
 142         if (property == ipProperty) {
 143             ipString = ipProperty.getSaveValue();
 144             ipChanged = true;
 145         }
 146         if (property == rotateProperty) {
 147             rotateAngleRad = Math.toRadians(rotateProperty.getValue());
 148         }
 149
 150     }
 151
 152     @Override
 153     public void disconnect() {
 154         bgThread.destroy();
 155         super.disconnect();
 156     }
 157
 158     @Override
 159     protected void paintComponent(Graphics g) {
 160         BufferedImage drawnImage = imageToDraw;
 161
 162         if (drawnImage != null) {
 163                 // cast the Graphics context into a Graphics2D
 164             Graphics2D g2d = (Graphics2D)g;
 165
 166             // get the existing Graphics transform and copy it so that we can perform scaling and rotation
 167             AffineTransform origXform = g2d.getTransform();
 168             AffineTransform newXform = (AffineTransform)(origXform.clone());
 169
 170             // find the center of the original image
 171             int origImageWidth = drawnImage.getWidth();
 172             int origImageHeight = drawnImage.getHeight();
 173             int imageCenterX = origImageWidth/2;
 174             int imageCenterY = origImageHeight/2;
 175
 176             // perform the desired scaling
 177             double panelWidth = getBounds().width;
 178             double panelHeight = getBounds().height;
 179             double panelCenterX = panelWidth/2.0;
 180             double panelCenterY = panelHeight/2.0;
 181             double rotatedImageWidth = origImageWidth * Math.abs(Math.cos(rotateAngleRad)) + origImageHeight * Math.abs(Math.sin(rotateAngleRad));
 182             double rotatedImageHeight = origImageWidth * Math.abs(Math.sin(rotateAngleRad)) + origImageHeight * Math.abs(Math.cos(rotateAngleRad));
 183
 184             // compute scaling needed
 185             double scale = Math.min(panelWidth / rotatedImageWidth, panelHeight / rotatedImageHeight);
 186
 187             // set the transform before drawing the image
 188             // 1 - translate the origin to the center of the panel
 189             // 2 - perform the desired rotation (rotation will be about origin)
 190             // 3 - perform the desired scaling (will scale centered about origin)
 191             newXform.translate(panelCenterX,  panelCenterY);
 192             newXform.rotate(rotateAngleRad);
 193             newXform.scale(scale, scale);
 194             g2d.setTransform(newXform);
 195
 196             // draw image so that the center of the image is at the "origin"; the transform will take care of the rotation and scaling
 197             g2d.drawImage(drawnImage, -imageCenterX, -imageCenterY, null);
 198
 199             // restore the original transform
 200             g2d.setTransform(origXform);
 201
 202             g.setColor(Color.PINK);
 203             g.drawString("FPS: "+lastFPS, 10, 10);
 204         } else {
 205             g.setColor(Color.PINK);
 206             g.fillRect(0, 0, getBounds().width, getBounds().height);
 207             g.setColor(Color.BLACK);
 208             g.drawString("NO CONNECTION", 10, 10);
 209         }
 210     }
 211 }