diff --git a/HiSprite.py b/HiSprite.py
index 7880bc4..ff7a539 100755
--- a/HiSprite.py
+++ b/HiSprite.py
@@ -167,7 +167,7 @@ class Listing(object):
 
 
 class Sprite(Listing):
-    def __init__(self, pngfile, assembler, screen, xdraw=False, processor="any"):
+    def __init__(self, pngfile, assembler, screen, xdraw=False, processor="any", name=""):
         Listing.__init__(self, assembler)
         self.screen = screen
 
@@ -176,7 +176,9 @@ class Sprite(Listing):
 
         self.xdraw = xdraw
         self.processor = processor
-        self.niceName = slugify(os.path.splitext(pngfile)[0])
+        if not name:
+            name = os.path.splitext(pngfile)[0]
+        self.niceName = slugify(name)
         self.width = pngdata[0]
         self.height = pngdata[1]
         self.pixelData = list(pngdata[2])
@@ -627,6 +629,7 @@ if __name__ == "__main__":
     parser.add_argument("-a", "--assembler", default="cc65", choices=["cc65","mac65"], help="Assembler syntax (default: %(default)s)")
     parser.add_argument("-p", "--processor", default="any", choices=["any","6502", "65C02"], help="Processor type (default: %(default)s)")
     parser.add_argument("-s", "--screen", default="hgrcolor", choices=["hgrcolor","hgrbw"], help="Screen format (default: %(default)s)")
+    parser.add_argument("-n", "--name", default="", help="Name for generated assembly function (default: based on image filename)")
     parser.add_argument("files", metavar="IMAGE", nargs="*", help="a PNG image [or a list of them]. PNG files must not have an alpha channel!")
     options, extra_args = parser.parse_known_args()
 
@@ -652,7 +655,7 @@ if __name__ == "__main__":
 
     for pngfile in options.files:
         try:
-            listings.append(Sprite(pngfile, assembler, screen, options.xdraw, options.processor))
+            listings.append(Sprite(pngfile, assembler, screen, options.xdraw, options.processor, options.name))
         except RuntimeError, e:
             print "%s: %s" % (pngfile, e)
             sys.exit(1)
diff --git a/Makefile.rob b/Makefile.rob
index c82f243..bc240bf 100644
--- a/Makefile.rob
+++ b/Makefile.rob
@@ -1,12 +1,15 @@
+COLORSPRITE = apple.png
+BWSPRITE = apple.png
+
 all: bwtest.dsk colortest.dsk
 
-bwtest.dsk:
-	python HiSprite.py -a mac65 -p 6502 -s hgrbw apple.png -t -c -r > apple.s
+bwtest.dsk: HiSprite.py bwtest.s $(BWSPRITE)
+	python HiSprite.py -a mac65 -p 6502 -s hgrbw $(BWSPRITE) -n bwsprite -t -c -r > bwsprite.s
 	atasm -obwtest.xex bwtest.s -Lbwtest.var -gbwtest.lst
 	atrcopy bwtest.dsk boot -b bwtest.xex --brun 6000 -f
 
-colortest.dsk: colortest.s boxw_mix.png
-	python HiSprite.py -a mac65 -p 6502 -s hgrcolor boxw_mix.png -t -c -r > boxw_mix.s
+colortest.dsk: HiSprite.py colortest.s $(COLORSPRITE)
+	python HiSprite.py -a mac65 -p 6502 -s hgrcolor $(COLORSPRITE) -n colorsprite -t -c -r > colorsprite.s
 	atasm -ocolortest.xex colortest.s -Lcolortest.var -gcolortest.lst
 	atrcopy colortest.dsk boot -b colortest.xex --brun 6000 -f
 
diff --git a/bwtest.s b/bwtest.s
index a367f37..e9b097d 100644
--- a/bwtest.s
+++ b/bwtest.s
@@ -47,7 +47,7 @@ draw
     lda #100
     sta PARAM0 ; x coord
 
-    jsr APPLE
+    jsr BWSPRITE
 
 wait
     jmp wait
@@ -71,4 +71,4 @@ clr1
     bcc clr1
     rts
 
-    .include apple.s
+    .include bwsprite.s
diff --git a/colortest.s b/colortest.s
index e94eae7..8db1764 100644
--- a/colortest.s
+++ b/colortest.s
@@ -47,7 +47,7 @@ draw
     lda #100
     sta PARAM0 ; x coord
 
-    jsr BOXW_MIX
+    jsr COLORSPRITE
 
 wait
     jmp wait
@@ -71,4 +71,4 @@ clr1
     bcc clr1
     rts
 
-    .include boxw_mix.s
+    .include colorsprite.s