Add some pageinfo test cases; found problem with inline images

.gitignore

@@ -8,4 +8,5 @@ tests/output/
 build/
 dist/
 *.egg-info/
-venv/
+venv/
+*/test/output

ocrmypdf/test/test_pageinfo.py

@@ -0,0 +1,111 @@
+#!/usr/bin/env python3
+
+from ocrmypdf import pageinfo
+from reportlab.pdfgen.canvas import Canvas
+from PIL import Image
+from tempfile import NamedTemporaryFile
+from contextlib import suppress
+import os
+import sys
+import shutil
+
+
+TEST_OUTPUT = os.path.join(os.path.dirname(__file__), 'output')
+
+
+def setup_module():
+    with suppress(FileNotFoundError):
+        shutil.rmtree(TEST_OUTPUT)
+    with suppress(FileExistsError):
+        os.mkdir(TEST_OUTPUT)
+
+
+def test_single_page_text():
+    filename = os.path.join(TEST_OUTPUT, 'text.pdf')
+    pdf = Canvas(filename, pagesize=(8*72, 6*72))
+    text = pdf.beginText()
+    text.setFont('Helvetica', 12)
+    text.setTextOrigin(4*72, 3*72)
+    text.textLine("Methink’st thou art a general offence and every"
+                  " man should beat thee.")
+    pdf.drawText(text)
+    pdf.showPage()
+    pdf.save()
+
+    pdfinfo = pageinfo.pdf_get_all_pageinfo(filename)
+
+    assert len(pdfinfo) == 1
+    page = pdfinfo[0]
+
+    assert page['has_text']
+    assert len(page['images']) == 0
+
+
+def test_single_page_image():
+    filename = os.path.join(TEST_OUTPUT, 'image-mono.pdf')
+    pdf = Canvas(filename, pagesize=(8*72, 6*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()
+
+    pdfinfo = pageinfo.pdf_get_all_pageinfo(filename)
+
+    assert len(pdfinfo) == 1
+    page = pdfinfo[0]
+
+    assert not page['has_text']
+    assert len(page['images']) == 1
+
+    pdfimage = page['images'][0]
+    assert pdfimage['width'] == 8
+    assert pdfimage['color'] == 'gray'
+
+    # While unexpected, this is correct
+    # PDF spec says /FlateDecode image must have /BitsPerComponent 8
+    # So mono images get upgraded to 8-bit
+    assert pdfimage['bpc'] == 8
+
+    # DPI in a 1"x1" is the image width
+    assert pdfimage['dpi_w'] == 8
+    assert pdfimage['dpi_h'] == 8
+
+
+def test_single_page_inline_image():
+    filename = os.path.join(TEST_OUTPUT, 'image-mono-inline.pdf')
+    pdf = Canvas(filename, pagesize=(8*72, 6*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.drawInlineImage(im_tmp.name, 0, 0, width=72, height=72)
+        pdf.showPage()
+        pdf.save()
+
+    pdfinfo = pageinfo.pdf_get_all_pageinfo(filename)
+
+    assert len(pdfinfo) == 1
+    page = pdfinfo[0]
+
+    assert not page['has_text']
+    assert len(page['images']) == 1
+
+    pdfimage = page['images'][0]
+    assert pdfimage['width'] == 8
+    assert pdfimage['color'] == 'gray'
+
+    # While unexpected, this is correct
+    # PDF spec says /FlateDecode image must have /BitsPerComponent 8
+    # So mono images get upgraded to 8-bit
+    assert pdfimage['bpc'] == 8
+
+    # DPI in a 1"x1" is the image width
+    assert pdfimage['dpi_w'] == 8
+    assert pdfimage['dpi_h'] == 8

tests/resources/NOTE.md

@@ -1,8 +0,0 @@
-All test resources must come from free public domain sources for copyright reasons.
-
-Test files do not necessarily produce perfect (or even good) OCR results.
-
-File 				| Source
---------------------|---------
-graph.pdf           | Wikimedia
-c02-22.pdf          | Project Gutenberg: https://www.gutenberg.org/files/76/76-h/images/c02-22.jpg

tests/resources/NOTE.rst

@@ -0,0 +1,13 @@
+All test resources must come from free public domain sources for
+copyright reasons.
+
+Test files do not necessarily produce perfect (or even good) OCR
+results.
+
++--------------+--------------------------------------------------------------------------------+
+| File         | Source                                                                         |
++==============+================================================================================+
+| graph.pdf    | Wikimedia                                                                      |
++--------------+--------------------------------------------------------------------------------+
+| c02-22.pdf   | Project Gutenberg: https://www.gutenberg.org/files/76/76-h/images/c02-22.jpg   |
++--------------+--------------------------------------------------------------------------------+