diff --git a/pixelflut.py b/pixelflut.py
index 078a28e..ba5359d 100755
--- a/pixelflut.py
+++ b/pixelflut.py
@@ -5,16 +5,16 @@ from PIL import Image, ImageColor
 import argparse
 import threading
 
-sizex = 800
+sizex = 800    
 sizey = 600
 
+
 XSPLIT = 5
 YSPLIT = 5
 
 threads = []
 
-effectivex = sizex
-effectivey = sizey
+dirtybox = (0,0,sizex,sizey)
 
 old_framebuffer = Image.new("RGBA", (sizex, sizey), None)
 framebuffer = Image.new("RGBA", (sizex, sizey), (0,0,0,0))
@@ -48,8 +48,9 @@ class DrawThread(threading.Thread):
         global framebuffer
         for x in range(xfrom,xto):
             for y in range(yfrom,yto):
-                value = b"%02X%02X%02X%02X"%framebuffer.getpixel((x,y))
-                buf += b"PX %b %b %b\n"%(bytes(str(x), "ascii"),bytes(str(y+args.yoffset), "ascii"),value)
+                if framebuffer.getpixel((x,y))[3] != 0:
+                    value = b"%02X%02X%02X%02X"%framebuffer.getpixel((x,y))
+                    buf += b"PX %d %d %b\n"%(x,y,value)
 
         s.send(buf)
         while args.repeat:
@@ -65,34 +66,41 @@ def draw():
 
     threads = []
 
-    chunkxsize = effectivex//XSPLIT
-    chunkysize = effectivey//YSPLIT
+    dirtysizex = (dirtybox[2]-dirtybox[0])
+    dirtysizey = (dirtybox[3]-dirtybox[1])
 
-    remainderx = effectivex % XSPLIT
-    remaindery = effectivey % YSPLIT
+    chunkxsize = dirtysizex//XSPLIT
+    chunkysize = dirtysizey//YSPLIT
+
+    remainderx = dirtysizex % XSPLIT
+    remaindery = dirtysizey % YSPLIT
+
+    offsetx = dirtybox[0]
+    offsety = dirtybox[1]
 
     xchunks = []
     ychunks = []
-    remainingx = effectivex
-    remainingy = effectivey
 
-    while remainingx > remainderx:
-        start = effectivex - remainingx
-        remainingx -= chunkxsize
-        stop = effectivex - remainingx
-        xchunks.append((start, stop))
+    allocatedx = 0
+
+    remainingx = (dirtybox[2]-dirtybox[0])
+    remainingy = (dirtybox[3]-dirtybox[0])
+
+    for i in range(dirtysizex//chunkxsize):
+        start = offsetx + (i*chunkxsize)
+        stop = offsetx + ((i+1)*chunkxsize)
+        xchunks.append((start,stop))
 
     if remainderx != 0:
-        xchunks.append((effectivex-remainingx, effectivex))
+        xchunks.append(((offsetx+dirtysizex)-remainderx, offsetx+remainderx))
 
-    while remainingy > remaindery:
-        start = effectivey - remainingy
-        remainingy -= chunkysize
-        stop = effectivey - remainingy
-        ychunks.append((start, stop))
+    for i in range(dirtysizey//chunkysize):
+        start = offsety + (i*chunkysize)
+        stop = offsety + ((i+1)*chunkysize)
+        ychunks.append((start,stop))
 
     if remaindery != 0:
-        ychunks.append((effectivey-remainingy, effectivey))
+        ychunks.append(((offsety+dirtysizey)-remaindery, offsety+remaindery))
 
     for xchunk in xchunks:
         for ychunk in ychunks:
@@ -109,12 +117,16 @@ elif args.image:
     coordinates = (0,0)
     image = Image.open(str(args.image))
     framebuffer.paste(image)
-    if not args.animate:
-        effectivex = min(image.size[0], sizex)
-        effectivey = min(image.size[1], sizey)
+    if args.animate:
+        dirtybox = (*coordinates, min(image.size[0]+coordinates[0], sizex), min(image.size[1]+coordinates[1], sizey))
+    else:
+        dirtybox = (0,0,min(image.size[0], sizex),min(image.size[1], sizey))
     draw()
     while args.animate:
         coordinates = (coordinates[0] + 5, coordinates[1] + 5)
+        if coordinates[0] >= sizex or coordinates[1] >= sizey:
+            break
+        dirtybox = (*coordinates, min(image.size[0]+coordinates[0], sizex), min(image.size[1]+coordinates[1], sizey))
         framebuffer = Image.new("RGBA", (sizex, sizey), (0,0,0,0))
         framebuffer.paste(image, coordinates)
         draw()