Changeset 11715

Timestamp:

2006-04-26T16:55:49+12:00 (18 years ago)

Author:

kjdon

Message:

committed Shaoquns version of the applet for the branch - version 1.7

Location:

branches/gsdl-2_70-distribution-branch/gsdl/src/java/org/nzdl/gsdl/GsdlCollageApplet

Files:

• DisplayImages.java (modified) (15 diffs)
• DownloadUrls.java (modified) (15 diffs)

branches/gsdl-2_70-distribution-branch/gsdl/src/java/org/nzdl/gsdl/GsdlCollageApplet/DisplayImages.java

@@ -12 +12 @@
  *
  *  Retrieves images from the download thread, determines an appropriate position
- *  for these images onscreen ensuring maximum whitespace coverage and minimal overlap
+ *  for thes  images onscreen ensuring maximum whitespace coverage and minimal overlap
  *  when possible. Draws images using advanced image processing techniques when applicable,
  *  such as fading the edges of an image and discolouring backgrounds. Also re-uses images
@@ -19 +19 @@
 public class DisplayImages extends Thread {
 
-    /** Decrements the alpha value between adjacent rows on the edge of an image<br>
-     *  Used to fade the edges faster than the rest of the image <br>
-     *  Only used when java2 parameter is true and advanced image processing
-     *  techniques may be applied */
-    static final int FADEVALUE = 3;
-    /** Defines the number of shades of white used to colour the backgrounds of white images <br>
-     *  These colours are used because when several white images appear in the collage
-     *  simultaneously it is difficult to distinguish their edges<br>
-     *  Only used when java2 parameter is true and advanced image processing
-     *  techniques may be applied */
-    static final int NO_OF_COLORS = 7;
 
     /** Will fire a removal operation when 4 images in the collage overlap a single area */
@@ -60 +49 @@
     protected boolean is_java2_     = false;
 
-    /** Holds images currently on display in the applet */
-    protected  Vector inuse_ready_    = null;
-
+  
     /** Holds images currently on display in the applet */
     protected Vector inuse_    = null;
     
+     /** Holds images ready to be used */
+    protected Vector inuse_ready_    = null;
+
     /** Holds previously displayed images for re-use */
     protected Vector notinuse_ = null;
@@ -87 +77 @@
     public static int [] [] used_space = null;
     
-    /** Defines the shades of white used to colour the backgrounds of white images <br>
-     *  These colours are used because when several white images appear in the collage
-     *  simultaneously it is difficult to distinguish their edges<br>
-     *  Only used when java2 parameter is true and advanced image processing
-     *  techniques may be applied */
-    int colorMask [] = {0xF8FFFF, 0xFFF8FF, 0xFFFFF8, 0xF8F8FF, 0xFFF8F8, 0xF8FFF8, 0xFAFAFA};
-
+  
     /**
      *  Starts the display images thread. Initialises variables using parameters and
@@ -114 +98 @@
 
     inuse_    = new Vector();
-        inuse_ready_   = new Vector();  
-    notinuse_ = new Vector();
+        notinuse_ = new Vector();
+        inuse_ready_ = new Vector();
     download_images_ = download_images;
     // sets width and height
@@ -146 +130 @@
         next_frame_ =  new Thread(new Runnable(){
                 public void run() {
-            try {
-
-            Thread curr_thread = Thread.currentThread();
-        
-            while (curr_thread == next_frame_) {
+          
+            Thread curr_thread = Thread.currentThread();
+            
+            while (curr_thread == next_frame_) {
+            try {       
+                Runtime rt = Runtime.getRuntime();
+                //System.out.println("total: "+rt.totalMemory());
+                //System.out.println("free:  "+rt.freeMemory());
+                rt.gc();             
+                        //System.out.println("**************next frame...");
                 next_frame();
-                
                 Thread.sleep(app_. refreshDelay_);
+               
                 curr_thread = Thread.currentThread();
+            } catch (Exception e) {
+                            e.printStackTrace(); 
+                break;
             }
-
-        
-            } catch (Exception e) {
-            e.printStackTrace();
-            }
+            }
+                    
+           
         }
 
@@ -166 +156 @@
         });
 
-       next_frame_.start();
+     next_frame_.start();
 
 
@@ -175 +165 @@
      *  @param y the y co-ordinate of the mouse
      *  @return the image that the user has clicked on or null if the user has clicked whitespace */
-   public synchronized CollageImage clickedOnImage(int x, int y)
+   public CollageImage clickedOnImage(int x, int y)
     {
     if (app_.verbosity() > 1)
@@ -182 +172 @@
     }
 
-    int no_images = inuse_.size() - 1;
+    
     // checks from last image down, as last images place will be at the top of the collage
-    for (int i= no_images; i >= 0; i--)
+    for (int i= inuse_.size() - 1; i >= 0; i--)
     {
         CollageImage collage_image = (CollageImage)inuse_.elementAt(i);
@@ -211 +201 @@
     public  void display_collage() 
     {
-
-        // get the number of images currently in the collage
-    final int no_images = inuse_.size();
-    
-
+    
     // if there is nothing new to add
-    if (no_images==0) return;
-    
+    if (inuse_.size()==0) return;
     
     // otherwise need to re-generate images
     if (app_.verbosity() >= 2)
-    {
-        System.err.println("Regenerating images: " +no_images);
-    }
+        {
+        //system.err.println("Regenerating images");
+        }
     
     // get each image currently onscreen inturn
-    for (int i=0; i<inuse_.size(); i++)
-    {
-        CollageImage collage_image = (CollageImage)inuse_.elementAt(i);
-       
-        Image image = collage_image.image_;
-        // images x and y dimensions
-        int image_x_dim = image.getWidth(app_);
-        int image_y_dim = image.getHeight(app_);
-
-        //int status = app_.checkImage(image,app_);
-
-        if ((image_x_dim>0) && (image_y_dim>0))
+    for (int i=0; i<inuse_.size();)
         {
+        CollageImage collage_image = (CollageImage)inuse_.elementAt(i);
+  
+                if (!collage_image.isValid()){
+            continue;
+        }       
+
+                int[] pixels = null;
         // the first time the image is painted, determine its position and size
         if (collage_image.fresh == true)
             {
-            // first time => randomly place doc
-            collage_image.setDimensions(image_x_dim,image_y_dim);
-            
-            // places and sizes the image
-            MyAffineTransform af = new MyAffineTransform(image_x_dim,image_y_dim);
-        
-            // sets location & size of collage image
-            collage_image.setAffineTransform(af, is_java2_);
-            
-             if (is_java2_) {
-                collage_image.image_ 
-                 = restoreAlpha(collage_image.image_, 0, 0, 
-                           collage_image.image_x_dim_, collage_image.image_y_dim_); 
-               
-            }
-            
-            
+            collage_image.process();
             }
         
         // advanced image processing may be used
         if (is_java2_)
-        {
-              
- 
-            // conducts fading and colouring of image
-            Image img = handlepixels(collage_image.image_, 0, 0, collage_image.image_x_dim_, 
-                        collage_image.image_y_dim_, i, collage_image.fresh ); 
-            collage_image.image_ = img;
+            {
+            // conducts fading and colouring of image
+            pixels = collage_image.handlepixels(inuse_.size()-i); 
+            }
         
- 
-        }
-
         if (collage_image.fresh) {
             collage_image.fresh = false;
         }
-           
-        }
-        else {
-        if (app_.verbosity()>=3) {
-            System.err.println("  Image ["+i+"] not ready yet!");
-        }
-        }
-        //finished_graphic_.drawImage(screen_buffer_,0,0,app_);
-    
-    }   
-    
-    // draws the finished image onscreen
-    finished_graphic_.drawImage(screen_buffer_,0,0,app_);
-    remove_old_images();
-    }
-
-
- /** loops through removing oldest images and reduces number of images if excessive overlap is occuring */
-    void remove_old_images() {
-   
-    // loops through removing oldest images that have almost faded completely
-    // and restricting the size of a simple collage to 25 images
-    int i=0;
-    while (i<inuse_.size())
-    {
-        CollageImage collage_image = (CollageImage)inuse_.elementAt(i);
-        
-        // if we remove when images have faded too much
-        if (is_java2_) {
-        if (checkFaded(collage_image.image_, 0, 0, collage_image.image_x_dim_, collage_image.image_y_dim_) || overlap)
-            {
+        
+        
+        // if we remove when images have faded too much
+        if (is_java2_) {
+            if (collage_image.checkFaded(pixels)|| overlap)
+            {
+                overlap = false;
+                
+                CollageImage removed_image = (CollageImage)inuse_.elementAt(i);
+                //System.out.println(removed_image.name_ + "is removed");
+                inuse_.remove(i);
+                // indicates space for this image is no longer used
+                for (int n = removed_image.xl_; n < (removed_image.xl_ + removed_image.image_x_dim_); n++)
+                for (int m = removed_image.yt_; m < (removed_image.yt_ + removed_image.image_y_dim_); m++)
+                    if(used_space[n][m] != 0) {
+                    used_space[n][m]--;
+                    if (used_space[n][m] > NO_IMAGES_OF_OVERLAP)
+                        overlap = true;
+                    }
+                
+                // sets the image as fresh and adds it to the vector of images previously seen
+                removed_image.fresh = true;
+                notinuse_.addElement(removed_image);
+            }
+            else{
+            i++;
+            }
+        }
+        else 
+            if (inuse_.size() > 25 || overlap) {
             overlap = false;
-
+            
             CollageImage removed_image = (CollageImage)inuse_.elementAt(i);
             inuse_.remove(i);
-
-            // restores alpha channel to represent a solid image
-            Image img = restoreAlpha(removed_image.image_, 0, 0, removed_image.image_x_dim_, removed_image.image_y_dim_); 
             
             // indicates space for this image is no longer used
@@ -322 +277 @@
                 if(used_space[n][m] != 0) {
                     used_space[n][m]--;
-                    if (used_space[n][m] > NO_IMAGES_OF_OVERLAP)
-                    overlap = true;
+                if (used_space[n][m] > NO_IMAGES_OF_OVERLAP)
+                    overlap = true;
                 }
-
+            
             // sets the image as fresh and adds it to the vector of images previously seen
-            removed_image.image_ = img;
             removed_image.fresh = true;
             notinuse_.addElement(removed_image);
             }
-        else {
-            i++;
-        }
-        }
-        // if we remove to prevent too many images being displayed simultaneously
-        else {
-        if (inuse_.size() > 25 || overlap) {
-            overlap = false;
-
-            CollageImage removed_image = (CollageImage)inuse_.elementAt(i);
-            inuse_.remove(i);
-
-            // indicates space for this image is no longer used
-            for (int n = removed_image.xl_; n < (removed_image.xl_ + removed_image.image_x_dim_); n++)
-            for (int m = removed_image.yt_; m < (removed_image.yt_ + removed_image.image_y_dim_); m++)
-                if(used_space[n][m] != 0) {
-                used_space[n][m]--;
-                if (used_space[n][m] > NO_IMAGES_OF_OVERLAP)
-                    overlap = true;
-                }
-            
-            // sets the image as fresh and adds it to the vector of images previously seen
-            removed_image.fresh = true;
-            notinuse_.addElement(removed_image);
-        }
-        else {
-            i++;
-        }
-        }
-    }
-     
-     
-    }
-
+            else{
+            i++;
+            }    
+        
+        }
+    }
+    
   
     /** Alters the images currently on display in the applet <br>
@@ -379 +306 @@
     {
     double random = Math.random();
-              
-
-    if (inuse_ready_.size() > 0){
+    
+     
+     if (inuse_ready_.size() > 0){
         int pos = (int) ((inuse_ready_.size() - 1) * random);
-        inuse_.addElement(inuse_ready_.remove(pos));
-    }
-        else if (notinuse_.size()>0)
-        {
-        int position = (int) ((notinuse_.size() - 1) * random);
-        Image image;
-        
-        CollageImage collage_image = (CollageImage)notinuse_.elementAt(position);
-        notinuse_.remove(position);
-        inuse_.addElement(collage_image);
-        
-        if (app_.verbosity()>3)
+        CollageImage collage_image = (CollageImage) inuse_ready_.remove(pos);
+        inuse_.addElement(collage_image);
+    }
+    else if (notinuse_.size()>0)
+        {
+            int position = (int) ((notinuse_.size() - 1) * random);
+            
+            CollageImage collage_image = (CollageImage)notinuse_.elementAt(position);
+            notinuse_.remove(position);
+            inuse_.addElement(collage_image);
+            
+            if (app_.verbosity()>3)
             {
             System.err.println("Re-using an image not on screen");
             }
-        }
-    // otherwise repaint the first image as the last image
-//  else if (inuse_.size() > 0){
-//      CollageImage removed_image = (CollageImage)inuse_.elementAt(0);
-        
-//      // empty the picture from the grid
-//      for (int n = removed_image.xl_; n < (removed_image.xl_ + removed_image.image_x_dim_); n++)
-//      for (int m = removed_image.yt_; m < (removed_image.yt_ + removed_image.image_y_dim_); m++)
-//          used_space[n][m]--;
-        
-//      // reset the alpha and add it
-//      removed_image.fresh = true;
-        
-//       if (is_java2_) {
-//      removed_image.image_ = restoreAlpha(removed_image.image_, 0, 0, 
-//                          removed_image.image_x_dim_, removed_image.image_y_dim_); 
-//      }
-        
-//      notinuse_.addElement(removed_image);
-//      inuse_.remove(0);
-//      if (app_.verbosity()>=4){
-//      System.err.println("Removing oldest image");
-//      }
-//  }
-    else{
-        if (app_.verbosity()>=4)
-        System.err.println("No images in download area");
-    }
-          display_collage();
-    
-    }
-    
-    /** Adjusts the colour and alpha value of an individual pixel <br>
-     *  If the image is being drawn for the first time, the RGB values are
-     *  extracted. If the pixel is close to white (RGB > 250) then an offwhite
-     *  colour is applied to this pixel.
-     *  This is done because when several white images appear in the collage
-     *  simultaneously it is difficult to distinguish their edges. <br>
-     *  This function also fades the alpha value of the pixel as the image ages.
-     *  The alpha value is more heavily decremented as pixels get closer to the
-     *  edge of the image
-     *
-     *  @param pixel the pixel to manipulate
-     *  @param p the position of the image in collage (representative of age)
-     *  @param fresh indicates whether or not the image is being drawn for the first time
-     *  @param edge indicates whether or not this pixel is near the edge of the image
-     *  @param fade the amount by which to fade this pixel
-     *  @return the adjusted pixel as an int */
-    public int handlesinglepixel(int pixel, int p, boolean fresh, boolean edge, int fade) {
-    
-    int newpixel = 0;
-
-        //changes the colour of the picture, only when first drawn
-    //and only if the pixel is close to white
-    if (fresh) {
-        
-        int red   = (pixel >> 16) & 0xff;
-        int green = (pixel >>  8) & 0xff;
-        int blue  = (pixel      ) & 0xff;
-        
-        if (red >= 250 && green >= 250 && blue >= 250) {
-        
-        int c = colorMask[((int) (p%NO_OF_COLORS))];
-
-        red = (c >> 16) & 0xff;
-        green = (c >> 8) & 0xff;
-        blue  = (c) & 0xff;
-        }
-
-        newpixel |= (red << 16) & 0x00ff0000;
-        newpixel |= (green << 8) & 0x0000ff00;
-        newpixel |= blue & 0x000000ff;
-    }
-
-    else {
-        newpixel |= pixel & 0x00ffffff;
-    }
-
-    int alpha = (pixel >> 24) & 0xff;
-
-    if (edge) {
-        // fade the edges more...
-        alpha = fade;
-    }
-    else if (alpha > 10 && !fresh) {
-        alpha -= 10;
-    }
-
-    newpixel |= (alpha << 24) & 0xff000000;
-    
-    return (newpixel);
-    }
-    
-    /** Fades and colours the image on a pixel-by-pixel basis <br>
-     *  First it grabs the pixels of the entire image and stores them in a 2D array.
-     *  Then a bound is calculated to indicate the point from which edge
-     *  fading should occur. The position of the bound will change in proportion
-     *  to the age of the image so that older images have a larger faded edge.
-     *  The area within the bounds, that forms the center of the image, is processed
-     *  first and faded by a standard alpha value. Then each edge of the image
-     *  is processed separately, creating a gradient fade from the true edge to the
-     *  position of the bound. <br>
-     *  The faded pixel array is then turned into a new image a returned.
-     *
-     *  @param img the image that requires processing
-     *  @param x the x co-ordinate of the image
-     *  @param y the y co-ordinate of the image
-     *  @param w the width of the image
-     *  @param h the height of the image
-     *  @param p the position of the image in the applet (indicates age)
-     *  @param fresh whether the image is being processed for the first time */
-
-    public  Image handlepixels(Image img, int x, int y, int w, int h, int p, boolean fresh) {
-    
-    // declare an array to hold the pixels
-    int[] pixels = new int[w * h];
-
-    // get the pixels of the image into the pixels array
-    PixelGrabber pg = new PixelGrabber(img, x, y, w, h, pixels, 0, w);
-    try {
-        pg.grabPixels();
-    
-    } catch (InterruptedException e) {
-        System.err.println("interrupted waiting for pixels!");
-        return img;
-    }
-    // check for any failures
-    if ((pg.getStatus() & ImageObserver.ABORT) != 0) {
-        System.err.println("image fetch aborted or errored");
-        return img;
-    }
-
-    // calculates the bound from which fading should begin
-    double bound = (inuse_.size() - p) * 0.01;
-    if (w > h)
-        bound *= w;
-    else
-        bound *= h;
-    int upperboundheight = h - (int) bound;
-    int upperboundwidth = w - (int) bound;
-    int lowerbound = (int) bound;
-
-    // loop through every pixel in the picture and handle it
-    for (int j = lowerbound; j < upperboundheight; j++) {
-        for (int i = lowerbound; i < upperboundwidth; i++) {
-        // width and height: x+i y+j
-        pixels[j * w + i] = handlesinglepixel(pixels[j * w + i], p, fresh, false, 255);
-        }
-    }
-
-    int fade = 0;
-    int fader = 0;
-    int corealpha = (pixels[(h/2) * w + (w/2)] >> 24) & 0xff;
-    
-    // top edge
-    for (int n = lowerbound; n >= 0; n--) {
-        fader = corealpha - fade;
-        if (fader < 0)
-        fader = 0;
-        
-        for (int m = 0; m < w; m++)
-        pixels[n * w + m] = handlesinglepixel(pixels[n * w + m], p, fresh, true, fader);
-        
-        fade+= FADEVALUE;
-    }
-
-    // bottom edge
-    fade = 0;
-    for (int n = upperboundheight; n < h; n++) {
-        fader = corealpha - fade;
-        if (fader < 0)
-        fader = 0;
-        for (int m = 0; m < w; m++)
-        pixels[n * w + m] = handlesinglepixel(pixels[n * w + m], p, fresh, true, fader);
-        
-        fade += FADEVALUE;
-    }
-
-    // left edge
-    fade = 0;
-    for (int n = lowerbound; n >= 0; n--) {
-        fader = corealpha - fade;
-        if (fader < 0)
-        fader = 0;
-        for (int m = 0; m < h; m++) {
-        if ( m < lowerbound && n > m);
-        else if ( m > upperboundheight && n > (h - m));
-        else 
-            pixels[m * w + n] = handlesinglepixel(pixels[m * w + n], p, fresh, true, fader);
-        }
-        fade += FADEVALUE;    
-    }
-    
-    // right edge
-    fade = 0;
-    for (int n = upperboundwidth; n < w; n++) {
-        fader = corealpha - fade;
-        if (fader < 0)
-        fader = 0;
-        for (int m = 0; m < h; m++) {
-        if ( m < lowerbound && (w - n) > m);
-        else if ( m > upperboundheight && (w - n) > (h - m));
-        else 
-            pixels[m * w + n] = handlesinglepixel(pixels[m * w + n], p, fresh, true, fader);
-        }
-        
-        fade += FADEVALUE;
-    }
-   
-    // set the pixels of the whole picture to the pixels array
-    pg.setPixels(0, 0, w, h, pg.getColorModel(), pixels, 0, w);
-
-    // create the new image and return it
-    return( app_.createImage(new MemoryImageSource(w, h, pixels, 0, w)) );
-    
-    }
-
-    /** Resets the alpha channel of an image so that it appears solid
-     *
-     *  @param img the image to restore
-     *  @param x the x co-ordinate of the image
-     *  @param y the y co-ordinate of the image
-     *  @param w the width of the image
-     *  @param h the height of the image */
-    public Image restoreAlpha(Image img, int x, int y, int w, int h) {
-      
-    // declare an array to hold the pixels
-    int[] pixels = new int[w * h];
-
-    // get the pixels of the image into the pixels array
-    PixelGrabber pg = new PixelGrabber(img, x, y, w, h, pixels, 0, w);
-
-    try {
-      
-        pg.grabPixels();
-          
-    } catch (InterruptedException e) {
-        System.err.println("interrupted waiting for pixels!");
-        return img;
-    }
-
-      
-    // check for any failures
-    if ((pg.getStatus() & ImageObserver.ABORT) != 0) {
-        System.err.println("image fetch aborted or errored");
-        return img;
-    }
-
-    // loop through every pixel in the picture and handle it
-    for (int j = 0; j < h; j++) {
-        for (int i = 0; i < w; i++) {
-        pixels[j * w + i] |= (255 << 24) & 0xff000000;
-        }
-    }
-
-    // set the pixels of the whole picture to the pixels array
-    pg.setPixels(0, 0, w, h, pg.getColorModel(), pixels, 0, w);
-
-    // create the new image and return it
-    return( app_.createImage(new MemoryImageSource(w, h, pixels, 0, w)) );
-    
-    }
-
-    /** Checks whether an image has faded to the point where it must be removed
-     *  from the collage.
-     *
-     *  @param img the image to restore
-     *  @param x the x co-ordinate of the image
-     *  @param y the y co-ordinate of the image
-     *  @param w the width of the image
-     *  @param h the height of the image */
-    public boolean checkFaded (Image img, int x, int y, int w, int h) {
-     if (w == 0 || h == 0) 
-         return false;
-    
-    // declare an array to hold the pixels
-    int[] pixels = new int[w * h];
-
-    // get the pixels of the image into the pixels array
-    PixelGrabber pg = new PixelGrabber(img, x, y, w, h, pixels, 0, w);
-    try {
-        pg.grabPixels();
-    
-    } catch (InterruptedException e) {
-        System.err.println("interrupted waiting for pixels!");
-        return false;
-    }
-    // check for any failures
-    if ((pg.getStatus() & ImageObserver.ABORT) != 0) {
-        System.err.println("image fetch aborted or errored");
-        return false;
-    }
-
-    // get the alpha value of the middle pixel of the image
-    int corealpha = (pixels[(h/2) * w + (w/2)] >> 24) & 0xff;
-    
-    if (corealpha < 2)
-        return true;
-
-    return false;
-    
-    }
+        }
+        else{
+        if (app_.verbosity()>=4)
+            System.err.println("No images in download area");
+        }
+
+    display_collage();
+    
+    }
+  
+  
 
     /** Paints the applet on the screen */
@@ -725 +361 @@
         if (collage_image.fresh) {
           if (app_.verbosity()>=1) {
-            System.err.println("doing nothing...  images in use is fresh.");
+            System.err.println("doing nothing...  "+ collage_image.name_ +" is fresh.");
            }
         }
@@ -742 +378 @@
         // simple image collage
         else
-            {
-            // add the image to the collage
+            {           // add the image to the collage
             
             screen_graphic_.drawImage(collage_image.image_, 
@@ -779 +414 @@
         
         while (curr_thread == this) {
-        CollageImage collage_image  = download_images_.getCollageImage();
-            if (collage_image !=null){
-                inuse_ready_.addElement(collage_image); 
-            }
-            else{
-                break;
-            }
-           curr_thread = Thread.currentThread();
-        }
-
-       
-        
+        if (inuse_ready_.size() >= 1){
+            Thread.sleep(1000);         
+            continue;
+        }    
+        CollageImage collage_image = download_images_.getCollageImage();
+    
+        if (collage_image !=null){
+            inuse_ready_.addElement(collage_image); 
+        }
+        curr_thread = Thread.currentThread();
+        }
+            
     } catch (Exception e) {
-        //e.printStackTrace();
+       e.printStackTrace();
            System.out.println("Display images thread is interrupted");
     }

branches/gsdl-2_70-distribution-branch/gsdl/src/java/org/nzdl/gsdl/GsdlCollageApplet/DownloadUrls.java

@@ -65 +65 @@
     int verbosity_ = 0;
 
-    protected boolean busy_ = false;
-    
+     /** Records all images which have already been examined */
+    Hashtable visited_images_  = null;
+        
     MediaTracker tracker;
 
@@ -99 +100 @@
     System.err.println("starting_url_ "  + starting_url +"\n"+
                        "href_musthave_ " +  href_musthave +"\n"+
-               "image_mustnothave_" + image_mustnothave+"\n"+
+               "image_mustnothave_ " + image_mustnothave+"\n"+
                "image_ignore_ "+  image_ignore+"\n"+
                "image_type_ "+ image_type+"\n"+
@@ -110 +111 @@
     }
 
-      public boolean getStatus(){
-    return busy_;
-
-    } 
-
+  
     /** Determines whether or not a url has already been examined
      *
@@ -128 +125 @@
      }
 
-    // if the url has been visited before, return true
+        // if the url has been visited before, return true
     if (visited_url_.containsKey(url_string))
     {
@@ -142 +139 @@
     return false;
     }
+
+  /** Determines whether or not an images or its screenview has been visited)
+     *  has already been examined
+     *
+     *  @param url_string the url to check
+     *  @param img_name the image to check
+     *  @return true if the url has been visited, false if not */
+    public boolean image_visited(String url_string, String img_name)
+    {
+    String hash_dir = url_string.substring(0,url_string.lastIndexOf("/"));  
+    
+    if ( visited_images_.containsKey(hash_dir)){
+        Hashtable hashed_images = (Hashtable)visited_images_.get(hash_dir);   
+       
+            if (img_name.startsWith("screenview")){
+        return true;
+        }
+
+        if (hashed_images.containsKey(img_name)){
+        return true;
+        }
+         
+            Enumeration enu = hashed_images.keys();
+            for(;enu.hasMoreElements();){
+        String name = (String)enu.nextElement();
+        if(name.startsWith("screenview")){
+            return true;
+        }
+        }
+    
+            hashed_images.put(img_name,"visited");           
+    }
+    else{
+        Hashtable hashed_images = new Hashtable();
+        hashed_images.put(img_name,"visited");
+        visited_images_.put(hash_dir,hashed_images);        
+    }
+         
+    return false;
+    }
+
+   
+
+
 
     /** Restricts the type of images that can be included in the collage
@@ -325 +366 @@
         // get the image from the url
         if (verbosity_>=2) {
-        //System.err.println("  ****Downloading image URL: " + url.toString());
-        }
+        System.err.println("  Downloading image URL: " + url.toString());
+        }
+            
+           if (image_visited(url.toString(),img_name)) return;
 
        int size = download_images_.downloadImage(tracker,url, from_url, img_name);
@@ -354 +397 @@
     public void rec_add_images(String new_url, int depth)
     {
-
+   
     if (already_visited(new_url)) return;
 
@@ -377 +420 @@
         // get all the <code><img src=</code> links into a vector
         Vector src_links = curl.getSrcLinks();
-        
+
+                
         if (verbosity_ >= 2) {
         System.err.println("  Got src links... there are " + src_links.size() + " of them.");
@@ -386 +430 @@
         URL url = (URL)src_links.get(i);
         String url_string  = url.toString();
-                
+            
         //System.err.println(" source links " + i + " ["  + url_string +"]");
 
@@ -440 +484 @@
         for (int i = 0; i < href_links.size(); i++) 
         {
+           
             URL url = (URL)href_links.get(i);
             String url_string  = url.toString();
-
-            //System.err.println(" href links " + i + "["  + url_string +"]");
-                    
+            //System.err.println(" href links " + i + "["  + url_string +"]");      
 
             if (image_file_extension(url_string))
             {
-                                      
+                                  
                 if (filter_image(url_string))
 
                 {
+                                        
                     img_name = url_string.substring(url_string.lastIndexOf("/") + 1, url_string.length());
 
@@ -471 +515 @@
                 if (filter_href(url_string,new_url,depth))
                 {
+        
                     rec_add_images(url_string,depth+1);
                     
@@ -493 +538 @@
     public void externalLinks() {
     external_links_ = null;
-
     try {
 
-        if (starting_url_.indexOf(document_root_) >= 0 ){ 
+        if (starting_url_ == null || (document_root_ != null && starting_url_.indexOf(document_root_) >= 0) ){ 
         return;
         }
@@ -510 +554 @@
         // split the line of the space, first part is the image, second part the link
         while (l != null) {
-
+    
         String tmp1 = new String();
         String tmp2 = new String();
@@ -523 +567 @@
             
             if (tmp2 != null) {
+            
             external_links_.put(tmp1, tmp2);
             //System.err.println(tmp1 + " " + tmp2);
@@ -543 +588 @@
     System.err.println("Starting download thread.");
     visited_url_ = new Hashtable();
-    
+    visited_images_ = new Hashtable();
+
         rec_add_images(starting_url_,1);
     download_images_.stopDownload();