Pillow/Tests/test_file_gif.py
Jon Dufresne 4de5477b61 Remove unnecessary unittest.main() boilerplate from test files
With the introduction and use of pytest, it is simple and easy to
execute specific tests in isolation through documented command line
arguments. Either by specifying the module path or through the `-k
EXPRESSION` argument. There is no longer any need to provide the
boilerplate:

    if __name__ == '__main__':
        unittest.main()

To every test file. It is simply noise.

The pattern remains in test files that aren't named with `test_*` as
those files are not discovered and executed by pytest by default.
2019-02-03 10:10:16 -08:00

657 lines
21 KiB
Python

from .helper import unittest, PillowTestCase, hopper, netpbm_available
from PIL import Image, ImagePalette, GifImagePlugin
from io import BytesIO
try:
from PIL import _webp
HAVE_WEBP = True
except ImportError:
HAVE_WEBP = False
codecs = dir(Image.core)
# sample gif stream
TEST_GIF = "Tests/images/hopper.gif"
with open(TEST_GIF, "rb") as f:
data = f.read()
class TestFileGif(PillowTestCase):
def setUp(self):
if "gif_encoder" not in codecs or "gif_decoder" not in codecs:
self.skipTest("gif support not available") # can this happen?
def test_sanity(self):
im = Image.open(TEST_GIF)
im.load()
self.assertEqual(im.mode, "P")
self.assertEqual(im.size, (128, 128))
self.assertEqual(im.format, "GIF")
self.assertEqual(im.info["version"], b"GIF89a")
def test_unclosed_file(self):
def open():
im = Image.open(TEST_GIF)
im.load()
self.assert_warning(None, open)
def test_invalid_file(self):
invalid_file = "Tests/images/flower.jpg"
self.assertRaises(SyntaxError,
GifImagePlugin.GifImageFile, invalid_file)
def test_optimize(self):
def test_grayscale(optimize):
im = Image.new("L", (1, 1), 0)
filename = BytesIO()
im.save(filename, "GIF", optimize=optimize)
return len(filename.getvalue())
def test_bilevel(optimize):
im = Image.new("1", (1, 1), 0)
test_file = BytesIO()
im.save(test_file, "GIF", optimize=optimize)
return len(test_file.getvalue())
self.assertEqual(test_grayscale(0), 800)
self.assertEqual(test_grayscale(1), 38)
self.assertEqual(test_bilevel(0), 800)
self.assertEqual(test_bilevel(1), 800)
def test_optimize_correctness(self):
# 256 color Palette image, posterize to > 128 and < 128 levels
# Size bigger and smaller than 512x512
# Check the palette for number of colors allocated.
# Check for correctness after conversion back to RGB
def check(colors, size, expected_palette_length):
# make an image with empty colors in the start of the palette range
im = Image.frombytes('P', (colors, colors),
bytes(bytearray(range(256-colors, 256))*colors))
im = im.resize((size, size))
outfile = BytesIO()
im.save(outfile, 'GIF')
outfile.seek(0)
reloaded = Image.open(outfile)
# check palette length
palette_length = max(i+1 for i, v in enumerate(reloaded.histogram()) if v)
self.assertEqual(expected_palette_length, palette_length)
self.assert_image_equal(im.convert('RGB'), reloaded.convert('RGB'))
# These do optimize the palette
check(128, 511, 128)
check(64, 511, 64)
check(4, 511, 4)
# These don't optimize the palette
check(128, 513, 256)
check(64, 513, 256)
check(4, 513, 256)
# other limits that don't optimize the palette
check(129, 511, 256)
check(255, 511, 256)
check(256, 511, 256)
def test_optimize_full_l(self):
im = Image.frombytes("L", (16, 16), bytes(bytearray(range(256))))
test_file = BytesIO()
im.save(test_file, "GIF", optimize=True)
self.assertEqual(im.mode, "L")
def test_roundtrip(self):
out = self.tempfile('temp.gif')
im = hopper()
im.save(out)
reread = Image.open(out)
self.assert_image_similar(reread.convert('RGB'), im, 50)
def test_roundtrip2(self):
# see https://github.com/python-pillow/Pillow/issues/403
out = self.tempfile('temp.gif')
im = Image.open(TEST_GIF)
im2 = im.copy()
im2.save(out)
reread = Image.open(out)
self.assert_image_similar(reread.convert('RGB'), hopper(), 50)
def test_roundtrip_save_all(self):
# Single frame image
out = self.tempfile('temp.gif')
im = hopper()
im.save(out, save_all=True)
reread = Image.open(out)
self.assert_image_similar(reread.convert('RGB'), im, 50)
# Multiframe image
im = Image.open("Tests/images/dispose_bgnd.gif")
out = self.tempfile('temp.gif')
im.save(out, save_all=True)
reread = Image.open(out)
self.assertEqual(reread.n_frames, 5)
def test_headers_saving_for_animated_gifs(self):
important_headers = ['background', 'version', 'duration', 'loop']
# Multiframe image
im = Image.open("Tests/images/dispose_bgnd.gif")
info = im.info.copy()
out = self.tempfile('temp.gif')
im.save(out, save_all=True)
reread = Image.open(out)
for header in important_headers:
self.assertEqual(
info[header],
reread.info[header]
)
def test_palette_handling(self):
# see https://github.com/python-pillow/Pillow/issues/513
im = Image.open(TEST_GIF)
im = im.convert('RGB')
im = im.resize((100, 100), Image.LANCZOS)
im2 = im.convert('P', palette=Image.ADAPTIVE, colors=256)
f = self.tempfile('temp.gif')
im2.save(f, optimize=True)
reloaded = Image.open(f)
self.assert_image_similar(im, reloaded.convert('RGB'), 10)
def test_palette_434(self):
# see https://github.com/python-pillow/Pillow/issues/434
def roundtrip(im, *args, **kwargs):
out = self.tempfile('temp.gif')
im.copy().save(out, *args, **kwargs)
reloaded = Image.open(out)
return reloaded
orig = "Tests/images/test.colors.gif"
im = Image.open(orig)
self.assert_image_similar(im, roundtrip(im), 1)
self.assert_image_similar(im, roundtrip(im, optimize=True), 1)
im = im.convert("RGB")
# check automatic P conversion
reloaded = roundtrip(im).convert('RGB')
self.assert_image_equal(im, reloaded)
@unittest.skipUnless(netpbm_available(), "netpbm not available")
def test_save_netpbm_bmp_mode(self):
img = Image.open(TEST_GIF).convert("RGB")
tempfile = self.tempfile("temp.gif")
GifImagePlugin._save_netpbm(img, 0, tempfile)
self.assert_image_similar(img, Image.open(tempfile).convert("RGB"), 0)
@unittest.skipUnless(netpbm_available(), "netpbm not available")
def test_save_netpbm_l_mode(self):
img = Image.open(TEST_GIF).convert("L")
tempfile = self.tempfile("temp.gif")
GifImagePlugin._save_netpbm(img, 0, tempfile)
self.assert_image_similar(img, Image.open(tempfile).convert("L"), 0)
def test_seek(self):
img = Image.open("Tests/images/dispose_none.gif")
framecount = 0
try:
while True:
framecount += 1
img.seek(img.tell() + 1)
except EOFError:
self.assertEqual(framecount, 5)
def test_seek_info(self):
im = Image.open("Tests/images/iss634.gif")
info = im.info.copy()
im.seek(1)
im.seek(0)
self.assertEqual(im.info, info)
def test_n_frames(self):
for path, n_frames in [
[TEST_GIF, 1],
['Tests/images/iss634.gif', 42]
]:
# Test is_animated before n_frames
im = Image.open(path)
self.assertEqual(im.is_animated, n_frames != 1)
# Test is_animated after n_frames
im = Image.open(path)
self.assertEqual(im.n_frames, n_frames)
self.assertEqual(im.is_animated, n_frames != 1)
def test_eoferror(self):
im = Image.open(TEST_GIF)
n_frames = im.n_frames
# Test seeking past the last frame
self.assertRaises(EOFError, im.seek, n_frames)
self.assertLess(im.tell(), n_frames)
# Test that seeking to the last frame does not raise an error
im.seek(n_frames-1)
def test_dispose_none(self):
img = Image.open("Tests/images/dispose_none.gif")
try:
while True:
img.seek(img.tell() + 1)
self.assertEqual(img.disposal_method, 1)
except EOFError:
pass
def test_dispose_background(self):
img = Image.open("Tests/images/dispose_bgnd.gif")
try:
while True:
img.seek(img.tell() + 1)
self.assertEqual(img.disposal_method, 2)
except EOFError:
pass
def test_dispose_previous(self):
img = Image.open("Tests/images/dispose_prev.gif")
try:
while True:
img.seek(img.tell() + 1)
self.assertEqual(img.disposal_method, 3)
except EOFError:
pass
def test_save_dispose(self):
out = self.tempfile('temp.gif')
im_list = [
Image.new('L', (100, 100), '#000'),
Image.new('L', (100, 100), '#111'),
Image.new('L', (100, 100), '#222'),
]
for method in range(0, 4):
im_list[0].save(
out,
save_all=True,
append_images=im_list[1:],
disposal=method
)
img = Image.open(out)
for _ in range(2):
img.seek(img.tell() + 1)
self.assertEqual(img.disposal_method, method)
# check per frame disposal
im_list[0].save(
out,
save_all=True,
append_images=im_list[1:],
disposal=tuple(range(len(im_list)))
)
img = Image.open(out)
for i in range(2):
img.seek(img.tell() + 1)
self.assertEqual(img.disposal_method, i+1)
def test_iss634(self):
img = Image.open("Tests/images/iss634.gif")
# seek to the second frame
img.seek(img.tell() + 1)
# all transparent pixels should be replaced with the color from the
# first frame
self.assertEqual(img.histogram()[img.info['transparency']], 0)
def test_duration(self):
duration = 1000
out = self.tempfile('temp.gif')
im = Image.new('L', (100, 100), '#000')
# Check that the argument has priority over the info settings
im.info['duration'] = 100
im.save(out, duration=duration)
reread = Image.open(out)
self.assertEqual(reread.info['duration'], duration)
def test_multiple_duration(self):
duration_list = [1000, 2000, 3000]
out = self.tempfile('temp.gif')
im_list = [
Image.new('L', (100, 100), '#000'),
Image.new('L', (100, 100), '#111'),
Image.new('L', (100, 100), '#222')
]
# duration as list
im_list[0].save(
out,
save_all=True,
append_images=im_list[1:],
duration=duration_list
)
reread = Image.open(out)
for duration in duration_list:
self.assertEqual(reread.info['duration'], duration)
try:
reread.seek(reread.tell() + 1)
except EOFError:
pass
# duration as tuple
im_list[0].save(
out,
save_all=True,
append_images=im_list[1:],
duration=tuple(duration_list)
)
reread = Image.open(out)
for duration in duration_list:
self.assertEqual(reread.info['duration'], duration)
try:
reread.seek(reread.tell() + 1)
except EOFError:
pass
def test_identical_frames(self):
duration_list = [1000, 1500, 2000, 4000]
out = self.tempfile('temp.gif')
im_list = [
Image.new('L', (100, 100), '#000'),
Image.new('L', (100, 100), '#000'),
Image.new('L', (100, 100), '#000'),
Image.new('L', (100, 100), '#111')
]
# duration as list
im_list[0].save(
out,
save_all=True,
append_images=im_list[1:],
duration=duration_list
)
reread = Image.open(out)
# Assert that the first three frames were combined
self.assertEqual(reread.n_frames, 2)
# Assert that the new duration is the total of the identical frames
self.assertEqual(reread.info['duration'], 4500)
def test_number_of_loops(self):
number_of_loops = 2
out = self.tempfile('temp.gif')
im = Image.new('L', (100, 100), '#000')
im.save(out, loop=number_of_loops)
reread = Image.open(out)
self.assertEqual(reread.info['loop'], number_of_loops)
def test_background(self):
out = self.tempfile('temp.gif')
im = Image.new('L', (100, 100), '#000')
im.info['background'] = 1
im.save(out)
reread = Image.open(out)
self.assertEqual(reread.info['background'], im.info['background'])
if HAVE_WEBP and _webp.HAVE_WEBPANIM:
im = Image.open("Tests/images/hopper.webp")
self.assertIsInstance(im.info['background'], tuple)
im.save(out)
def test_comment(self):
im = Image.open(TEST_GIF)
self.assertEqual(im.info['comment'],
b"File written by Adobe Photoshop\xa8 4.0")
out = self.tempfile('temp.gif')
im = Image.new('L', (100, 100), '#000')
im.info['comment'] = b"Test comment text"
im.save(out)
reread = Image.open(out)
self.assertEqual(reread.info['comment'], im.info['comment'])
def test_comment_over_255(self):
out = self.tempfile('temp.gif')
im = Image.new('L', (100, 100), '#000')
comment = b"Test comment text"
while len(comment) < 256:
comment += comment
im.info['comment'] = comment
im.save(out)
reread = Image.open(out)
self.assertEqual(reread.info['comment'], comment)
def test_zero_comment_subblocks(self):
im = Image.open('Tests/images/hopper_zero_comment_subblocks.gif')
expected = Image.open(TEST_GIF)
self.assert_image_equal(im, expected)
def test_version(self):
out = self.tempfile('temp.gif')
def assertVersionAfterSave(im, version):
im.save(out)
reread = Image.open(out)
self.assertEqual(reread.info["version"], version)
# Test that GIF87a is used by default
im = Image.new('L', (100, 100), '#000')
assertVersionAfterSave(im, b"GIF87a")
# Test setting the version to 89a
im = Image.new('L', (100, 100), '#000')
im.info["version"] = b"89a"
assertVersionAfterSave(im, b"GIF89a")
# Test that adding a GIF89a feature changes the version
im.info["transparency"] = 1
assertVersionAfterSave(im, b"GIF89a")
# Test that a GIF87a image is also saved in that format
im = Image.open("Tests/images/test.colors.gif")
assertVersionAfterSave(im, b"GIF87a")
# Test that a GIF89a image is also saved in that format
im.info["version"] = b"GIF89a"
assertVersionAfterSave(im, b"GIF87a")
def test_append_images(self):
out = self.tempfile('temp.gif')
# Test appending single frame images
im = Image.new('RGB', (100, 100), '#f00')
ims = [Image.new('RGB', (100, 100), color) for color
in ['#0f0', '#00f']]
im.copy().save(out, save_all=True, append_images=ims)
reread = Image.open(out)
self.assertEqual(reread.n_frames, 3)
# Tests appending using a generator
def imGenerator(ims):
for im in ims:
yield im
im.save(out, save_all=True, append_images=imGenerator(ims))
reread = Image.open(out)
self.assertEqual(reread.n_frames, 3)
# Tests appending single and multiple frame images
im = Image.open("Tests/images/dispose_none.gif")
ims = [Image.open("Tests/images/dispose_prev.gif")]
im.save(out, save_all=True, append_images=ims)
reread = Image.open(out)
self.assertEqual(reread.n_frames, 10)
def test_transparent_optimize(self):
# from issue #2195, if the transparent color is incorrectly
# optimized out, gif loses transparency
# Need a palette that isn't using the 0 color, and one
# that's > 128 items where the transparent color is actually
# the top palette entry to trigger the bug.
data = bytes(bytearray(range(1, 254)))
palette = ImagePalette.ImagePalette("RGB", list(range(256))*3)
im = Image.new('L', (253, 1))
im.frombytes(data)
im.putpalette(palette)
out = self.tempfile('temp.gif')
im.save(out, transparency=253)
reloaded = Image.open(out)
self.assertEqual(reloaded.info['transparency'], 253)
def test_rgb_transparency(self):
out = self.tempfile('temp.gif')
# Single frame
im = Image.new('RGB', (1, 1))
im.info['transparency'] = (255, 0, 0)
self.assert_warning(UserWarning, im.save, out)
reloaded = Image.open(out)
self.assertNotIn('transparency', reloaded.info)
# Multiple frames
im = Image.new('RGB', (1, 1))
im.info['transparency'] = b""
ims = [Image.new('RGB', (1, 1))]
self.assert_warning(UserWarning,
im.save, out, save_all=True, append_images=ims)
reloaded = Image.open(out)
self.assertNotIn('transparency', reloaded.info)
def test_bbox(self):
out = self.tempfile('temp.gif')
im = Image.new('RGB', (100, 100), '#fff')
ims = [Image.new("RGB", (100, 100), '#000')]
im.save(out, save_all=True, append_images=ims)
reread = Image.open(out)
self.assertEqual(reread.n_frames, 2)
def test_palette_save_L(self):
# generate an L mode image with a separate palette
im = hopper('P')
im_l = Image.frombytes('L', im.size, im.tobytes())
palette = bytes(bytearray(im.getpalette()))
out = self.tempfile('temp.gif')
im_l.save(out, palette=palette)
reloaded = Image.open(out)
self.assert_image_equal(reloaded.convert('RGB'), im.convert('RGB'))
def test_palette_save_P(self):
# pass in a different palette, then construct what the image
# would look like.
# Forcing a non-straight grayscale palette.
im = hopper('P')
palette = bytes(bytearray([255-i//3 for i in range(768)]))
out = self.tempfile('temp.gif')
im.save(out, palette=palette)
reloaded = Image.open(out)
im.putpalette(palette)
self.assert_image_equal(reloaded, im)
def test_palette_save_ImagePalette(self):
# pass in a different palette, as an ImagePalette.ImagePalette
# effectively the same as test_palette_save_P
im = hopper('P')
palette = ImagePalette.ImagePalette('RGB', list(range(256))[::-1]*3)
out = self.tempfile('temp.gif')
im.save(out, palette=palette)
reloaded = Image.open(out)
im.putpalette(palette)
self.assert_image_equal(reloaded, im)
def test_save_I(self):
# Test saving something that would trigger the auto-convert to 'L'
im = hopper('I')
out = self.tempfile('temp.gif')
im.save(out)
reloaded = Image.open(out)
self.assert_image_equal(reloaded.convert('L'), im.convert('L'))
def test_getdata(self):
# test getheader/getdata against legacy values
# Create a 'P' image with holes in the palette
im = Image._wedge().resize((16, 16))
im.putpalette(ImagePalette.ImagePalette('RGB'))
im.info = {'background': 0}
passed_palette = bytes(bytearray([255-i//3 for i in range(768)]))
GifImagePlugin._FORCE_OPTIMIZE = True
try:
h = GifImagePlugin.getheader(im, passed_palette)
d = GifImagePlugin.getdata(im)
import pickle
# Enable to get target values on pre-refactor version
# with open('Tests/images/gif_header_data.pkl', 'wb') as f:
# pickle.dump((h, d), f, 1)
with open('Tests/images/gif_header_data.pkl', 'rb') as f:
(h_target, d_target) = pickle.load(f)
self.assertEqual(h, h_target)
self.assertEqual(d, d_target)
finally:
GifImagePlugin._FORCE_OPTIMIZE = False
def test_lzw_bits(self):
# see https://github.com/python-pillow/Pillow/issues/2811
im = Image.open('Tests/images/issue_2811.gif')
self.assertEqual(im.tile[0][3][0], 11) # LZW bits
# codec error prepatch
im.load()