win32 platform

Scripts/thresholder.py

@@ -0,0 +1,74 @@
+#!e:\oml-win32\local_platform\bin\python.exe
+#
+# The Python Imaging Library
+# $Id$
+#
+# this demo script illustrates how a 1-bit BitmapImage can be used
+# as a dynamically updated overlay
+#
+
+try:
+    from tkinter import *
+except ImportError:
+    from Tkinter import *
+
+from PIL import Image, ImageTk
+import sys
+
+#
+# an image viewer
+
+
+class UI(Frame):
+    def __init__(self, master, im, value=128):
+        Frame.__init__(self, master)
+
+        self.image = im
+        self.value = value
+
+        self.canvas = Canvas(self, width=im.size[0], height=im.size[1])
+        self.backdrop = ImageTk.PhotoImage(im)
+        self.canvas.create_image(0, 0, image=self.backdrop, anchor=NW)
+        self.canvas.pack()
+
+        scale = Scale(self, orient=HORIZONTAL, from_=0, to=255,
+                      resolution=1, command=self.update_scale, length=256)
+        scale.set(value)
+        scale.bind("<ButtonRelease-1>", self.redraw)
+        scale.pack()
+
+        # uncomment the following line for instant feedback (might
+        # be too slow on some platforms)
+        # self.redraw()
+
+    def update_scale(self, value):
+        self.value = eval(value)
+
+        self.redraw()
+
+    def redraw(self, event=None):
+
+        # create overlay (note the explicit conversion to mode "1")
+        im = self.image.point(lambda v, t=self.value: v >= t, "1")
+        self.overlay = ImageTk.BitmapImage(im, foreground="green")
+
+        # update canvas
+        self.canvas.delete("overlay")
+        self.canvas.create_image(0, 0, image=self.overlay, anchor=NW,
+                                 tags="overlay")
+
+# --------------------------------------------------------------------
+# main
+
+root = Tk()
+
+im = Image.open(sys.argv[1])
+
+if im.mode != "L":
+    im = im.convert("L")
+
+# im.thumbnail((320,200))
+
+UI(root, im).pack()
+
+root.mainloop()