Pillow/Tests/test_file_gif.py
2019-06-13 18:53:42 +03:00

656 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_seek_rewind(self):
im = Image.open("Tests/images/iss634.gif")
im.seek(2)
im.seek(1)
expected = Image.open("Tests/images/iss634.gif")
expected.seek(1)
self.assert_image_equal(im, expected)
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()
def test_extents(self):
im = Image.open("Tests/images/test_extents.gif")
self.assertEqual(im.size, (100, 100))
im.seek(1)
self.assertEqual(im.size, (150, 150))