Use img2pdf in test case because it does a better job

ocrmypdf/test/test_pageinfo.py

@@ -10,6 +10,7 @@ import os
 import sys
 import shutil
 import pytest
+import img2pdf
 from pkg_resources import Requirement, resource_filename
 
 req = Requirement.parse('ocrmypdf')
@@ -47,16 +48,16 @@ def test_single_page_text():
 
 def test_single_page_image():
     filename = os.path.join(TEST_OUTPUT, 'image-mono.pdf')
-    pdf = Canvas(filename, pagesize=(72, 72))
+
     with NamedTemporaryFile() as im_tmp:
         im = Image.new('1', (8, 8), 0)
         for n in range(8):
             im.putpixel((n, n), 1)
         im.save(im_tmp.name, format='PNG')
-        # Draw image in a 72x72 pt or 1"x1" area
-        pdf.drawImage(im_tmp.name, 0, 0, width=72, height=72)
-        pdf.showPage()
-        pdf.save()
+
+        pdf_bytes = img2pdf.convert([im_tmp.name], dpi=8)
+        with open(filename, 'wb') as pdf:
+            pdf.write(pdf_bytes)
 
     pdfinfo = pageinfo.pdf_get_all_pageinfo(filename)
 
@@ -68,7 +69,7 @@ def test_single_page_image():
 
     pdfimage = page['images'][0]
     assert pdfimage['width'] == 8
-    # assert pdfimage['color'] == 'gray'
+    assert pdfimage['color'] == 'gray'
 
     # While unexpected, this is correct
     # PDF spec says /FlateDecode image must have /BitsPerComponent 8

setup.py

@@ -204,6 +204,10 @@ setup(
         'reportlab>=3.1.44',
         'PyPDF2>=1.25.1'
     ],
+    test_requires=[
+        'img2pdf>=0.1.5',
+        'pytest>=2.7.2'
+    ],
     entry_points={
         'console_scripts': [
             'ocrmypdf = ocrmypdf.main:run_pipeline'