Adding script to generate a bunch of filled scantrons.

scantron.py

@@ -35,9 +35,9 @@ def scan(self, data, path):
             shape = sub_img.shape
 
             ratio = float(shape[0]) / float(shape[1])
-            brightness = float(num_ones)/float(num_all)
+            darkness = float(num_ones)/float(num_all)
 
-            if brightness > 0.95 and abs(ratio - 1.0) < 0.1 and shape[0] > 14:
+            if darkness > 0.95 and abs(ratio - 1.0) < 0.1 and shape[0] > 14:
                 x1, x2 = slices[i][1].start, slices[i][1].stop
                 y1, y2 = slices[i][0].start, slices[i][0].stop
 
@@ -64,8 +64,6 @@ def scan(self, data, path):
         rotation = math.atan2(bl[1] - tl[1], bl[0] - tl[0])
         print('rotation: ' + str(rotation))
 
-        #img.show()
-
 
 class Scantron:
     def __init__(self, filename, spacing=0.3*inch):

testcase.py

@@ -0,0 +1,51 @@
+#!/usr/bin/env python2
+
+from scantron import *
+import PythonMagick
+from pyPdf import PdfFileReader
+from PIL import Image
+
+data = [
+    Field('foo', 'Foo foo foo', int),
+    Field('bar', 'Bar bar bar', int),
+    Field('baz', 'Baz baz baz', int),
+    Field('laber', 'Laber laber', bool),
+]
+
+# Generate PDF
+st = Scantron('test.pdf')
+st.set_box_sizes(box_size=0.2*inch, box_spacing=0.3*inch)
+st.populate(data, matches=1, collate='no')
+st.save()
+
+# Convert PDF to a series of pictures
+pages = []
+
+pdf = PdfFileReader(file('test.pdf', 'rb'))
+
+for page in range(pdf.getNumPages()):
+    #page += 1
+    name = 'test_image_%d.png' % page
+
+    im = PythonMagick.Image()
+    im.density('200')
+    im.read('test.pdf[%d]' % page)
+    im.write(name)
+
+    pages.append(name)
+
+# Create a series of transformations to apply
+transformations = [
+    lambda x: x.rotate(10, expand=False),
+    lambda x: x.rotate(-10, expand=False),
+]
+
+tf = 0
+
+# Take all pictures and modify them in different ways
+for page in pages:
+    im = Image.open(page).convert('L')
+    im = transformations[tf](im)
+    im.save(page)
+
+    tf = (tf + 1) % len(transformations)