607
.venv/lib/python3.9/site-packages/PIL/ImageOps.py
Normal file
607
.venv/lib/python3.9/site-packages/PIL/ImageOps.py
Normal file
@@ -0,0 +1,607 @@
|
||||
#
|
||||
# The Python Imaging Library.
|
||||
# $Id$
|
||||
#
|
||||
# standard image operations
|
||||
#
|
||||
# History:
|
||||
# 2001-10-20 fl Created
|
||||
# 2001-10-23 fl Added autocontrast operator
|
||||
# 2001-12-18 fl Added Kevin's fit operator
|
||||
# 2004-03-14 fl Fixed potential division by zero in equalize
|
||||
# 2005-05-05 fl Fixed equalize for low number of values
|
||||
#
|
||||
# Copyright (c) 2001-2004 by Secret Labs AB
|
||||
# Copyright (c) 2001-2004 by Fredrik Lundh
|
||||
#
|
||||
# See the README file for information on usage and redistribution.
|
||||
#
|
||||
|
||||
import functools
|
||||
import operator
|
||||
import re
|
||||
|
||||
from . import Image, ImageDraw
|
||||
|
||||
#
|
||||
# helpers
|
||||
|
||||
|
||||
def _border(border):
|
||||
if isinstance(border, tuple):
|
||||
if len(border) == 2:
|
||||
left, top = right, bottom = border
|
||||
elif len(border) == 4:
|
||||
left, top, right, bottom = border
|
||||
else:
|
||||
left = top = right = bottom = border
|
||||
return left, top, right, bottom
|
||||
|
||||
|
||||
def _color(color, mode):
|
||||
if isinstance(color, str):
|
||||
from . import ImageColor
|
||||
|
||||
color = ImageColor.getcolor(color, mode)
|
||||
return color
|
||||
|
||||
|
||||
def _lut(image, lut):
|
||||
if image.mode == "P":
|
||||
# FIXME: apply to lookup table, not image data
|
||||
raise NotImplementedError("mode P support coming soon")
|
||||
elif image.mode in ("L", "RGB"):
|
||||
if image.mode == "RGB" and len(lut) == 256:
|
||||
lut = lut + lut + lut
|
||||
return image.point(lut)
|
||||
else:
|
||||
raise OSError("not supported for this image mode")
|
||||
|
||||
|
||||
#
|
||||
# actions
|
||||
|
||||
|
||||
def autocontrast(image, cutoff=0, ignore=None, mask=None, preserve_tone=False):
|
||||
"""
|
||||
Maximize (normalize) image contrast. This function calculates a
|
||||
histogram of the input image (or mask region), removes ``cutoff`` percent of the
|
||||
lightest and darkest pixels from the histogram, and remaps the image
|
||||
so that the darkest pixel becomes black (0), and the lightest
|
||||
becomes white (255).
|
||||
|
||||
:param image: The image to process.
|
||||
:param cutoff: The percent to cut off from the histogram on the low and
|
||||
high ends. Either a tuple of (low, high), or a single
|
||||
number for both.
|
||||
:param ignore: The background pixel value (use None for no background).
|
||||
:param mask: Histogram used in contrast operation is computed using pixels
|
||||
within the mask. If no mask is given the entire image is used
|
||||
for histogram computation.
|
||||
:param preserve_tone: Preserve image tone in Photoshop-like style autocontrast.
|
||||
|
||||
.. versionadded:: 8.2.0
|
||||
|
||||
:return: An image.
|
||||
"""
|
||||
if preserve_tone:
|
||||
histogram = image.convert("L").histogram(mask)
|
||||
else:
|
||||
histogram = image.histogram(mask)
|
||||
|
||||
lut = []
|
||||
for layer in range(0, len(histogram), 256):
|
||||
h = histogram[layer : layer + 256]
|
||||
if ignore is not None:
|
||||
# get rid of outliers
|
||||
try:
|
||||
h[ignore] = 0
|
||||
except TypeError:
|
||||
# assume sequence
|
||||
for ix in ignore:
|
||||
h[ix] = 0
|
||||
if cutoff:
|
||||
# cut off pixels from both ends of the histogram
|
||||
if not isinstance(cutoff, tuple):
|
||||
cutoff = (cutoff, cutoff)
|
||||
# get number of pixels
|
||||
n = 0
|
||||
for ix in range(256):
|
||||
n = n + h[ix]
|
||||
# remove cutoff% pixels from the low end
|
||||
cut = n * cutoff[0] // 100
|
||||
for lo in range(256):
|
||||
if cut > h[lo]:
|
||||
cut = cut - h[lo]
|
||||
h[lo] = 0
|
||||
else:
|
||||
h[lo] -= cut
|
||||
cut = 0
|
||||
if cut <= 0:
|
||||
break
|
||||
# remove cutoff% samples from the high end
|
||||
cut = n * cutoff[1] // 100
|
||||
for hi in range(255, -1, -1):
|
||||
if cut > h[hi]:
|
||||
cut = cut - h[hi]
|
||||
h[hi] = 0
|
||||
else:
|
||||
h[hi] -= cut
|
||||
cut = 0
|
||||
if cut <= 0:
|
||||
break
|
||||
# find lowest/highest samples after preprocessing
|
||||
for lo in range(256):
|
||||
if h[lo]:
|
||||
break
|
||||
for hi in range(255, -1, -1):
|
||||
if h[hi]:
|
||||
break
|
||||
if hi <= lo:
|
||||
# don't bother
|
||||
lut.extend(list(range(256)))
|
||||
else:
|
||||
scale = 255.0 / (hi - lo)
|
||||
offset = -lo * scale
|
||||
for ix in range(256):
|
||||
ix = int(ix * scale + offset)
|
||||
if ix < 0:
|
||||
ix = 0
|
||||
elif ix > 255:
|
||||
ix = 255
|
||||
lut.append(ix)
|
||||
return _lut(image, lut)
|
||||
|
||||
|
||||
def colorize(image, black, white, mid=None, blackpoint=0, whitepoint=255, midpoint=127):
|
||||
"""
|
||||
Colorize grayscale image.
|
||||
This function calculates a color wedge which maps all black pixels in
|
||||
the source image to the first color and all white pixels to the
|
||||
second color. If ``mid`` is specified, it uses three-color mapping.
|
||||
The ``black`` and ``white`` arguments should be RGB tuples or color names;
|
||||
optionally you can use three-color mapping by also specifying ``mid``.
|
||||
Mapping positions for any of the colors can be specified
|
||||
(e.g. ``blackpoint``), where these parameters are the integer
|
||||
value corresponding to where the corresponding color should be mapped.
|
||||
These parameters must have logical order, such that
|
||||
``blackpoint <= midpoint <= whitepoint`` (if ``mid`` is specified).
|
||||
|
||||
:param image: The image to colorize.
|
||||
:param black: The color to use for black input pixels.
|
||||
:param white: The color to use for white input pixels.
|
||||
:param mid: The color to use for midtone input pixels.
|
||||
:param blackpoint: an int value [0, 255] for the black mapping.
|
||||
:param whitepoint: an int value [0, 255] for the white mapping.
|
||||
:param midpoint: an int value [0, 255] for the midtone mapping.
|
||||
:return: An image.
|
||||
"""
|
||||
|
||||
# Initial asserts
|
||||
assert image.mode == "L"
|
||||
if mid is None:
|
||||
assert 0 <= blackpoint <= whitepoint <= 255
|
||||
else:
|
||||
assert 0 <= blackpoint <= midpoint <= whitepoint <= 255
|
||||
|
||||
# Define colors from arguments
|
||||
black = _color(black, "RGB")
|
||||
white = _color(white, "RGB")
|
||||
if mid is not None:
|
||||
mid = _color(mid, "RGB")
|
||||
|
||||
# Empty lists for the mapping
|
||||
red = []
|
||||
green = []
|
||||
blue = []
|
||||
|
||||
# Create the low-end values
|
||||
for i in range(0, blackpoint):
|
||||
red.append(black[0])
|
||||
green.append(black[1])
|
||||
blue.append(black[2])
|
||||
|
||||
# Create the mapping (2-color)
|
||||
if mid is None:
|
||||
|
||||
range_map = range(0, whitepoint - blackpoint)
|
||||
|
||||
for i in range_map:
|
||||
red.append(black[0] + i * (white[0] - black[0]) // len(range_map))
|
||||
green.append(black[1] + i * (white[1] - black[1]) // len(range_map))
|
||||
blue.append(black[2] + i * (white[2] - black[2]) // len(range_map))
|
||||
|
||||
# Create the mapping (3-color)
|
||||
else:
|
||||
|
||||
range_map1 = range(0, midpoint - blackpoint)
|
||||
range_map2 = range(0, whitepoint - midpoint)
|
||||
|
||||
for i in range_map1:
|
||||
red.append(black[0] + i * (mid[0] - black[0]) // len(range_map1))
|
||||
green.append(black[1] + i * (mid[1] - black[1]) // len(range_map1))
|
||||
blue.append(black[2] + i * (mid[2] - black[2]) // len(range_map1))
|
||||
for i in range_map2:
|
||||
red.append(mid[0] + i * (white[0] - mid[0]) // len(range_map2))
|
||||
green.append(mid[1] + i * (white[1] - mid[1]) // len(range_map2))
|
||||
blue.append(mid[2] + i * (white[2] - mid[2]) // len(range_map2))
|
||||
|
||||
# Create the high-end values
|
||||
for i in range(0, 256 - whitepoint):
|
||||
red.append(white[0])
|
||||
green.append(white[1])
|
||||
blue.append(white[2])
|
||||
|
||||
# Return converted image
|
||||
image = image.convert("RGB")
|
||||
return _lut(image, red + green + blue)
|
||||
|
||||
|
||||
def contain(image, size, method=Image.BICUBIC):
|
||||
"""
|
||||
Returns a resized version of the image, set to the maximum width and height
|
||||
within the requested size, while maintaining the original aspect ratio.
|
||||
|
||||
:param image: The image to resize and crop.
|
||||
:param size: The requested output size in pixels, given as a
|
||||
(width, height) tuple.
|
||||
:param method: Resampling method to use. Default is
|
||||
:py:attr:`PIL.Image.BICUBIC`. See :ref:`concept-filters`.
|
||||
:return: An image.
|
||||
"""
|
||||
|
||||
im_ratio = image.width / image.height
|
||||
dest_ratio = size[0] / size[1]
|
||||
|
||||
if im_ratio != dest_ratio:
|
||||
if im_ratio > dest_ratio:
|
||||
new_height = int(image.height / image.width * size[0])
|
||||
if new_height != size[1]:
|
||||
size = (size[0], new_height)
|
||||
else:
|
||||
new_width = int(image.width / image.height * size[1])
|
||||
if new_width != size[0]:
|
||||
size = (new_width, size[1])
|
||||
return image.resize(size, resample=method)
|
||||
|
||||
|
||||
def pad(image, size, method=Image.BICUBIC, color=None, centering=(0.5, 0.5)):
|
||||
"""
|
||||
Returns a resized and padded version of the image, expanded to fill the
|
||||
requested aspect ratio and size.
|
||||
|
||||
:param image: The image to resize and crop.
|
||||
:param size: The requested output size in pixels, given as a
|
||||
(width, height) tuple.
|
||||
:param method: Resampling method to use. Default is
|
||||
:py:attr:`PIL.Image.BICUBIC`. See :ref:`concept-filters`.
|
||||
:param color: The background color of the padded image.
|
||||
:param centering: Control the position of the original image within the
|
||||
padded version.
|
||||
|
||||
(0.5, 0.5) will keep the image centered
|
||||
(0, 0) will keep the image aligned to the top left
|
||||
(1, 1) will keep the image aligned to the bottom
|
||||
right
|
||||
:return: An image.
|
||||
"""
|
||||
|
||||
resized = contain(image, size, method)
|
||||
if resized.size == size:
|
||||
out = resized
|
||||
else:
|
||||
out = Image.new(image.mode, size, color)
|
||||
if resized.width != size[0]:
|
||||
x = int((size[0] - resized.width) * max(0, min(centering[0], 1)))
|
||||
out.paste(resized, (x, 0))
|
||||
else:
|
||||
y = int((size[1] - resized.height) * max(0, min(centering[1], 1)))
|
||||
out.paste(resized, (0, y))
|
||||
return out
|
||||
|
||||
|
||||
def crop(image, border=0):
|
||||
"""
|
||||
Remove border from image. The same amount of pixels are removed
|
||||
from all four sides. This function works on all image modes.
|
||||
|
||||
.. seealso:: :py:meth:`~PIL.Image.Image.crop`
|
||||
|
||||
:param image: The image to crop.
|
||||
:param border: The number of pixels to remove.
|
||||
:return: An image.
|
||||
"""
|
||||
left, top, right, bottom = _border(border)
|
||||
return image.crop((left, top, image.size[0] - right, image.size[1] - bottom))
|
||||
|
||||
|
||||
def scale(image, factor, resample=Image.BICUBIC):
|
||||
"""
|
||||
Returns a rescaled image by a specific factor given in parameter.
|
||||
A factor greater than 1 expands the image, between 0 and 1 contracts the
|
||||
image.
|
||||
|
||||
:param image: The image to rescale.
|
||||
:param factor: The expansion factor, as a float.
|
||||
:param resample: Resampling method to use. Default is
|
||||
:py:attr:`PIL.Image.BICUBIC`. See :ref:`concept-filters`.
|
||||
:returns: An :py:class:`~PIL.Image.Image` object.
|
||||
"""
|
||||
if factor == 1:
|
||||
return image.copy()
|
||||
elif factor <= 0:
|
||||
raise ValueError("the factor must be greater than 0")
|
||||
else:
|
||||
size = (round(factor * image.width), round(factor * image.height))
|
||||
return image.resize(size, resample)
|
||||
|
||||
|
||||
def deform(image, deformer, resample=Image.BILINEAR):
|
||||
"""
|
||||
Deform the image.
|
||||
|
||||
:param image: The image to deform.
|
||||
:param deformer: A deformer object. Any object that implements a
|
||||
``getmesh`` method can be used.
|
||||
:param resample: An optional resampling filter. Same values possible as
|
||||
in the PIL.Image.transform function.
|
||||
:return: An image.
|
||||
"""
|
||||
return image.transform(image.size, Image.MESH, deformer.getmesh(image), resample)
|
||||
|
||||
|
||||
def equalize(image, mask=None):
|
||||
"""
|
||||
Equalize the image histogram. This function applies a non-linear
|
||||
mapping to the input image, in order to create a uniform
|
||||
distribution of grayscale values in the output image.
|
||||
|
||||
:param image: The image to equalize.
|
||||
:param mask: An optional mask. If given, only the pixels selected by
|
||||
the mask are included in the analysis.
|
||||
:return: An image.
|
||||
"""
|
||||
if image.mode == "P":
|
||||
image = image.convert("RGB")
|
||||
h = image.histogram(mask)
|
||||
lut = []
|
||||
for b in range(0, len(h), 256):
|
||||
histo = [_f for _f in h[b : b + 256] if _f]
|
||||
if len(histo) <= 1:
|
||||
lut.extend(list(range(256)))
|
||||
else:
|
||||
step = (functools.reduce(operator.add, histo) - histo[-1]) // 255
|
||||
if not step:
|
||||
lut.extend(list(range(256)))
|
||||
else:
|
||||
n = step // 2
|
||||
for i in range(256):
|
||||
lut.append(n // step)
|
||||
n = n + h[i + b]
|
||||
return _lut(image, lut)
|
||||
|
||||
|
||||
def expand(image, border=0, fill=0):
|
||||
"""
|
||||
Add border to the image
|
||||
|
||||
:param image: The image to expand.
|
||||
:param border: Border width, in pixels.
|
||||
:param fill: Pixel fill value (a color value). Default is 0 (black).
|
||||
:return: An image.
|
||||
"""
|
||||
left, top, right, bottom = _border(border)
|
||||
width = left + image.size[0] + right
|
||||
height = top + image.size[1] + bottom
|
||||
color = _color(fill, image.mode)
|
||||
if image.mode == "P" and image.palette:
|
||||
out = Image.new(image.mode, (width, height))
|
||||
out.putpalette(image.palette)
|
||||
out.paste(image, (left, top))
|
||||
|
||||
draw = ImageDraw.Draw(out)
|
||||
draw.rectangle((0, 0, width - 1, height - 1), outline=color, width=border)
|
||||
else:
|
||||
out = Image.new(image.mode, (width, height), color)
|
||||
out.paste(image, (left, top))
|
||||
return out
|
||||
|
||||
|
||||
def fit(image, size, method=Image.BICUBIC, bleed=0.0, centering=(0.5, 0.5)):
|
||||
"""
|
||||
Returns a resized and cropped version of the image, cropped to the
|
||||
requested aspect ratio and size.
|
||||
|
||||
This function was contributed by Kevin Cazabon.
|
||||
|
||||
:param image: The image to resize and crop.
|
||||
:param size: The requested output size in pixels, given as a
|
||||
(width, height) tuple.
|
||||
:param method: Resampling method to use. Default is
|
||||
:py:attr:`PIL.Image.BICUBIC`. See :ref:`concept-filters`.
|
||||
:param bleed: Remove a border around the outside of the image from all
|
||||
four edges. The value is a decimal percentage (use 0.01 for
|
||||
one percent). The default value is 0 (no border).
|
||||
Cannot be greater than or equal to 0.5.
|
||||
:param centering: Control the cropping position. Use (0.5, 0.5) for
|
||||
center cropping (e.g. if cropping the width, take 50% off
|
||||
of the left side, and therefore 50% off the right side).
|
||||
(0.0, 0.0) will crop from the top left corner (i.e. if
|
||||
cropping the width, take all of the crop off of the right
|
||||
side, and if cropping the height, take all of it off the
|
||||
bottom). (1.0, 0.0) will crop from the bottom left
|
||||
corner, etc. (i.e. if cropping the width, take all of the
|
||||
crop off the left side, and if cropping the height take
|
||||
none from the top, and therefore all off the bottom).
|
||||
:return: An image.
|
||||
"""
|
||||
|
||||
# by Kevin Cazabon, Feb 17/2000
|
||||
# kevin@cazabon.com
|
||||
# http://www.cazabon.com
|
||||
|
||||
# ensure centering is mutable
|
||||
centering = list(centering)
|
||||
|
||||
if not 0.0 <= centering[0] <= 1.0:
|
||||
centering[0] = 0.5
|
||||
if not 0.0 <= centering[1] <= 1.0:
|
||||
centering[1] = 0.5
|
||||
|
||||
if not 0.0 <= bleed < 0.5:
|
||||
bleed = 0.0
|
||||
|
||||
# calculate the area to use for resizing and cropping, subtracting
|
||||
# the 'bleed' around the edges
|
||||
|
||||
# number of pixels to trim off on Top and Bottom, Left and Right
|
||||
bleed_pixels = (bleed * image.size[0], bleed * image.size[1])
|
||||
|
||||
live_size = (
|
||||
image.size[0] - bleed_pixels[0] * 2,
|
||||
image.size[1] - bleed_pixels[1] * 2,
|
||||
)
|
||||
|
||||
# calculate the aspect ratio of the live_size
|
||||
live_size_ratio = live_size[0] / live_size[1]
|
||||
|
||||
# calculate the aspect ratio of the output image
|
||||
output_ratio = size[0] / size[1]
|
||||
|
||||
# figure out if the sides or top/bottom will be cropped off
|
||||
if live_size_ratio == output_ratio:
|
||||
# live_size is already the needed ratio
|
||||
crop_width = live_size[0]
|
||||
crop_height = live_size[1]
|
||||
elif live_size_ratio >= output_ratio:
|
||||
# live_size is wider than what's needed, crop the sides
|
||||
crop_width = output_ratio * live_size[1]
|
||||
crop_height = live_size[1]
|
||||
else:
|
||||
# live_size is taller than what's needed, crop the top and bottom
|
||||
crop_width = live_size[0]
|
||||
crop_height = live_size[0] / output_ratio
|
||||
|
||||
# make the crop
|
||||
crop_left = bleed_pixels[0] + (live_size[0] - crop_width) * centering[0]
|
||||
crop_top = bleed_pixels[1] + (live_size[1] - crop_height) * centering[1]
|
||||
|
||||
crop = (crop_left, crop_top, crop_left + crop_width, crop_top + crop_height)
|
||||
|
||||
# resize the image and return it
|
||||
return image.resize(size, method, box=crop)
|
||||
|
||||
|
||||
def flip(image):
|
||||
"""
|
||||
Flip the image vertically (top to bottom).
|
||||
|
||||
:param image: The image to flip.
|
||||
:return: An image.
|
||||
"""
|
||||
return image.transpose(Image.FLIP_TOP_BOTTOM)
|
||||
|
||||
|
||||
def grayscale(image):
|
||||
"""
|
||||
Convert the image to grayscale.
|
||||
|
||||
:param image: The image to convert.
|
||||
:return: An image.
|
||||
"""
|
||||
return image.convert("L")
|
||||
|
||||
|
||||
def invert(image):
|
||||
"""
|
||||
Invert (negate) the image.
|
||||
|
||||
:param image: The image to invert.
|
||||
:return: An image.
|
||||
"""
|
||||
lut = []
|
||||
for i in range(256):
|
||||
lut.append(255 - i)
|
||||
return _lut(image, lut)
|
||||
|
||||
|
||||
def mirror(image):
|
||||
"""
|
||||
Flip image horizontally (left to right).
|
||||
|
||||
:param image: The image to mirror.
|
||||
:return: An image.
|
||||
"""
|
||||
return image.transpose(Image.FLIP_LEFT_RIGHT)
|
||||
|
||||
|
||||
def posterize(image, bits):
|
||||
"""
|
||||
Reduce the number of bits for each color channel.
|
||||
|
||||
:param image: The image to posterize.
|
||||
:param bits: The number of bits to keep for each channel (1-8).
|
||||
:return: An image.
|
||||
"""
|
||||
lut = []
|
||||
mask = ~(2 ** (8 - bits) - 1)
|
||||
for i in range(256):
|
||||
lut.append(i & mask)
|
||||
return _lut(image, lut)
|
||||
|
||||
|
||||
def solarize(image, threshold=128):
|
||||
"""
|
||||
Invert all pixel values above a threshold.
|
||||
|
||||
:param image: The image to solarize.
|
||||
:param threshold: All pixels above this greyscale level are inverted.
|
||||
:return: An image.
|
||||
"""
|
||||
lut = []
|
||||
for i in range(256):
|
||||
if i < threshold:
|
||||
lut.append(i)
|
||||
else:
|
||||
lut.append(255 - i)
|
||||
return _lut(image, lut)
|
||||
|
||||
|
||||
def exif_transpose(image):
|
||||
"""
|
||||
If an image has an EXIF Orientation tag, return a new image that is
|
||||
transposed accordingly. Otherwise, return a copy of the image.
|
||||
|
||||
:param image: The image to transpose.
|
||||
:return: An image.
|
||||
"""
|
||||
exif = image.getexif()
|
||||
orientation = exif.get(0x0112)
|
||||
method = {
|
||||
2: Image.FLIP_LEFT_RIGHT,
|
||||
3: Image.ROTATE_180,
|
||||
4: Image.FLIP_TOP_BOTTOM,
|
||||
5: Image.TRANSPOSE,
|
||||
6: Image.ROTATE_270,
|
||||
7: Image.TRANSVERSE,
|
||||
8: Image.ROTATE_90,
|
||||
}.get(orientation)
|
||||
if method is not None:
|
||||
transposed_image = image.transpose(method)
|
||||
transposed_exif = transposed_image.getexif()
|
||||
if 0x0112 in transposed_exif:
|
||||
del transposed_exif[0x0112]
|
||||
if "exif" in transposed_image.info:
|
||||
transposed_image.info["exif"] = transposed_exif.tobytes()
|
||||
elif "Raw profile type exif" in transposed_image.info:
|
||||
transposed_image.info[
|
||||
"Raw profile type exif"
|
||||
] = transposed_exif.tobytes().hex()
|
||||
elif "XML:com.adobe.xmp" in transposed_image.info:
|
||||
transposed_image.info["XML:com.adobe.xmp"] = re.sub(
|
||||
r'tiff:Orientation="([0-9])"',
|
||||
"",
|
||||
transposed_image.info["XML:com.adobe.xmp"],
|
||||
)
|
||||
return transposed_image
|
||||
return image.copy()
|
Reference in New Issue
Block a user