# HG changeset patch
# User Paul Boddie <paul@boddie.org.uk>
# Date 1444488526 -7200
# Node ID be170b4cfcde3c59c95db456707050402e816344
# Parent  7f5faa940ac985dc0703bb75e5651a0de577d9e0
Moved image previewing into the extension module.

diff -r 7f5faa940ac9 -r be170b4cfcde optimiser.py
--- a/optimiser.py	Sat Oct 10 16:41:10 2015 +0200
+++ b/optimiser.py	Sat Oct 10 16:48:46 2015 +0200
@@ -72,26 +72,6 @@
 
     return im.resize((width, height))
 
-def preview_image(pim, half_resolution_preview=False):
-
-    "Return a preview copy of image 'pim'."
-
-    width, height = pim.size
-    imp = pim.copy()
-    im = SimpleImage(list(pim.getdata()), pim.size)
-    step = half_resolution_preview and 2 or 1
-
-    for y in range(0, height):
-        for x in range(0, width, step):
-            rgb = im.getpixel((x, y))
-            value = get_value(rgb)
-            im.putpixel((x, y), value)
-            if half_resolution_preview:
-                im.putpixel((x+1, y), value)
-
-    imp.putdata(im.getdata())
-    return imp
-
 def convert_image(pim):
 
     "Convert image 'pim' to an appropriate output representation."
@@ -219,7 +199,11 @@
     # Generate a preview if requested.
 
     if preview:
-        preview_image(im, half_resolution_preview).save(preview_filename)
+        imp = im.copy()
+        sim = SimpleImage(list(im.getdata()), im.size)
+        simp = preview_image(sim, half_resolution_preview)
+        imp.putdata(simp.getdata())
+        imp.save(preview_filename)
 
     # Generate an output image if requested.
 
diff -r 7f5faa940ac9 -r be170b4cfcde optimiserlib.py
--- a/optimiserlib.py	Sat Oct 10 16:41:10 2015 +0200
+++ b/optimiserlib.py	Sat Oct 10 16:48:46 2015 +0200
@@ -249,6 +249,27 @@
                     rgb = amplify_rgb(rgb, brighten and 0.5 / brighten or 2 * darken)
                 im.putpixel((x, y), rgb)
 
+def preview_image(im, half_resolution_preview=False):
+
+    "Return a preview copy of image 'im'."
+
+    width, height = im.size
+    imp = im.copy()
+    if half_resolution_preview:
+        step = 2
+    else:
+        step = 1
+
+    for y in range(0, height):
+        for x in range(0, width, step):
+            rgb = im.getpixel((x, y))
+            value = get_value(rgb)
+            imp.putpixel((x, y), value)
+            if half_resolution_preview:
+                imp.putpixel((x+1, y), value)
+
+    return imp
+
 class SimpleImage:
 
     "An image behaving like PIL.Image."
@@ -294,5 +315,6 @@
     count_colours(im, 4)
 
     process_image(im, 1.0, 0.0, 1.0, 0.0)
+    preview_image(im, False)
 
 # vim: tabstop=4 expandtab shiftwidth=4