565 lines
19 KiB
Python
565 lines
19 KiB
Python
|
#
|
||
|
|
# The Python Imaging Library
|
||
|
|
# $Id$
|
||
|
|
#
|
||
|
|
# drawing interface operations
|
||
|
|
#
|
||
|
|
# History:
|
||
|
|
# 1996-04-13 fl Created (experimental)
|
||
|
|
# 1996-08-07 fl Filled polygons, ellipses.
|
||
|
|
# 1996-08-13 fl Added text support
|
||
|
|
# 1998-06-28 fl Handle I and F images
|
||
|
|
# 1998-12-29 fl Added arc; use arc primitive to draw ellipses
|
||
|
|
# 1999-01-10 fl Added shape stuff (experimental)
|
||
|
|
# 1999-02-06 fl Added bitmap support
|
||
|
|
# 1999-02-11 fl Changed all primitives to take options
|
||
|
|
# 1999-02-20 fl Fixed backwards compatibility
|
||
|
|
# 2000-10-12 fl Copy on write, when necessary
|
||
|
|
# 2001-02-18 fl Use default ink for bitmap/text also in fill mode
|
||
|
|
# 2002-10-24 fl Added support for CSS-style color strings
|
||
|
|
# 2002-12-10 fl Added experimental support for RGBA-on-RGB drawing
|
||
|
|
# 2002-12-11 fl Refactored low-level drawing API (work in progress)
|
||
|
|
# 2004-08-26 fl Made Draw() a factory function, added getdraw() support
|
||
|
|
# 2004-09-04 fl Added width support to line primitive
|
||
|
|
# 2004-09-10 fl Added font mode handling
|
||
|
|
# 2006-06-19 fl Added font bearing support (getmask2)
|
||
|
|
#
|
||
|
|
# Copyright (c) 1997-2006 by Secret Labs AB
|
||
|
|
# Copyright (c) 1996-2006 by Fredrik Lundh
|
||
|
|
#
|
||
|
|
# See the README file for information on usage and redistribution.
|
||
|
|
#
|
||
|
|
|
||
|
|
import math
|
||
|
|
import numbers
|
||
|
|
|
||
|
|
from . import Image, ImageColor
|
||
|
|
|
||
|
|
|
||
|
|
"""
|
||
|
|
A simple 2D drawing interface for PIL images.
|
||
|
|
<p>
|
||
|
|
Application code should use the <b>Draw</b> factory, instead of
|
||
|
|
directly.
|
||
|
|
"""
|
||
|
|
|
||
|
|
|
||
|
|
class ImageDraw:
|
||
|
|
def __init__(self, im, mode=None):
|
||
|
|
"""
|
||
|
|
Create a drawing instance.
|
||
|
|
|
||
|
|
:param im: The image to draw in.
|
||
|
|
:param mode: Optional mode to use for color values. For RGB
|
||
|
|
images, this argument can be RGB or RGBA (to blend the
|
||
|
|
drawing into the image). For all other modes, this argument
|
||
|
|
must be the same as the image mode. If omitted, the mode
|
||
|
|
defaults to the mode of the image.
|
||
|
|
"""
|
||
|
|
im.load()
|
||
|
|
if im.readonly:
|
||
|
|
im._copy() # make it writeable
|
||
|
|
blend = 0
|
||
|
|
if mode is None:
|
||
|
|
mode = im.mode
|
||
|
|
if mode != im.mode:
|
||
|
|
if mode == "RGBA" and im.mode == "RGB":
|
||
|
|
blend = 1
|
||
|
|
else:
|
||
|
|
raise ValueError("mode mismatch")
|
||
|
|
if mode == "P":
|
||
|
|
self.palette = im.palette
|
||
|
|
else:
|
||
|
|
self.palette = None
|
||
|
|
self.im = im.im
|
||
|
|
self.draw = Image.core.draw(self.im, blend)
|
||
|
|
self.mode = mode
|
||
|
|
if mode in ("I", "F"):
|
||
|
|
self.ink = self.draw.draw_ink(1)
|
||
|
|
else:
|
||
|
|
self.ink = self.draw.draw_ink(-1)
|
||
|
|
if mode in ("1", "P", "I", "F"):
|
||
|
|
# FIXME: fix Fill2 to properly support matte for I+F images
|
||
|
|
self.fontmode = "1"
|
||
|
|
else:
|
||
|
|
self.fontmode = "L" # aliasing is okay for other modes
|
||
|
|
self.fill = 0
|
||
|
|
self.font = None
|
||
|
|
|
||
|
|
def getfont(self):
|
||
|
|
"""
|
||
|
|
Get the current default font.
|
||
|
|
|
||
|
|
:returns: An image font."""
|
||
|
|
if not self.font:
|
||
|
|
# FIXME: should add a font repository
|
||
|
|
from . import ImageFont
|
||
|
|
|
||
|
|
self.font = ImageFont.load_default()
|
||
|
|
return self.font
|
||
|
|
|
||
|
|
def _getink(self, ink, fill=None):
|
||
|
|
if ink is None and fill is None:
|
||
|
|
if self.fill:
|
||
|
|
fill = self.ink
|
||
|
|
else:
|
||
|
|
ink = self.ink
|
||
|
|
else:
|
||
|
|
if ink is not None:
|
||
|
|
if isinstance(ink, str):
|
||
|
|
ink = ImageColor.getcolor(ink, self.mode)
|
||
|
|
if self.palette and not isinstance(ink, numbers.Number):
|
||
|
|
ink = self.palette.getcolor(ink)
|
||
|
|
ink = self.draw.draw_ink(ink)
|
||
|
|
if fill is not None:
|
||
|
|
if isinstance(fill, str):
|
||
|
|
fill = ImageColor.getcolor(fill, self.mode)
|
||
|
|
if self.palette and not isinstance(fill, numbers.Number):
|
||
|
|
fill = self.palette.getcolor(fill)
|
||
|
|
fill = self.draw.draw_ink(fill)
|
||
|
|
return ink, fill
|
||
|
|
|
||
|
|
def arc(self, xy, start, end, fill=None, width=0):
|
||
|
|
"""Draw an arc."""
|
||
|
|
ink, fill = self._getink(fill)
|
||
|
|
if ink is not None:
|
||
|
|
self.draw.draw_arc(xy, start, end, ink, width)
|
||
|
|
|
||
|
|
def bitmap(self, xy, bitmap, fill=None):
|
||
|
|
"""Draw a bitmap."""
|
||
|
|
bitmap.load()
|
||
|
|
ink, fill = self._getink(fill)
|
||
|
|
if ink is None:
|
||
|
|
ink = fill
|
||
|
|
if ink is not None:
|
||
|
|
self.draw.draw_bitmap(xy, bitmap.im, ink)
|
||
|
|
|
||
|
|
def chord(self, xy, start, end, fill=None, outline=None, width=0):
|
||
|
|
"""Draw a chord."""
|
||
|
|
ink, fill = self._getink(outline, fill)
|
||
|
|
if fill is not None:
|
||
|
|
self.draw.draw_chord(xy, start, end, fill, 1)
|
||
|
|
if ink is not None and ink != fill:
|
||
|
|
self.draw.draw_chord(xy, start, end, ink, 0, width)
|
||
|
|
|
||
|
|
def ellipse(self, xy, fill=None, outline=None, width=0):
|
||
|
|
"""Draw an ellipse."""
|
||
|
|
ink, fill = self._getink(outline, fill)
|
||
|
|
if fill is not None:
|
||
|
|
self.draw.draw_ellipse(xy, fill, 1)
|
||
|
|
if ink is not None and ink != fill:
|
||
|
|
self.draw.draw_ellipse(xy, ink, 0, width)
|
||
|
|
|
||
|
|
def line(self, xy, fill=None, width=0, joint=None):
|
||
|
|
"""Draw a line, or a connected sequence of line segments."""
|
||
|
|
ink = self._getink(fill)[0]
|
||
|
|
if ink is not None:
|
||
|
|
self.draw.draw_lines(xy, ink, width)
|
||
|
|
if joint == "curve" and width > 4:
|
||
|
|
for i in range(1, len(xy) - 1):
|
||
|
|
point = xy[i]
|
||
|
|
angles = [
|
||
|
|
math.degrees(math.atan2(end[0] - start[0], start[1] - end[1]))
|
||
|
|
% 360
|
||
|
|
for start, end in ((xy[i - 1], point), (point, xy[i + 1]))
|
||
|
|
]
|
||
|
|
if angles[0] == angles[1]:
|
||
|
|
# This is a straight line, so no joint is required
|
||
|
|
continue
|
||
|
|
|
||
|
|
def coord_at_angle(coord, angle):
|
||
|
|
x, y = coord
|
||
|
|
angle -= 90
|
||
|
|
distance = width / 2 - 1
|
||
|
|
return tuple(
|
||
|
|
[
|
||
|
|
p + (math.floor(p_d) if p_d > 0 else math.ceil(p_d))
|
||
|
|
for p, p_d in (
|
||
|
|
(x, distance * math.cos(math.radians(angle))),
|
||
|
|
(y, distance * math.sin(math.radians(angle))),
|
||
|
|
)
|
||
|
|
]
|
||
|
|
)
|
||
|
|
|
||
|
|
flipped = (
|
||
|
|
angles[1] > angles[0] and angles[1] - 180 > angles[0]
|
||
|
|
) or (angles[1] < angles[0] and angles[1] + 180 > angles[0])
|
||
|
|
coords = [
|
||
|
|
(point[0] - width / 2 + 1, point[1] - width / 2 + 1),
|
||
|
|
(point[0] + width / 2 - 1, point[1] + width / 2 - 1),
|
||
|
|
]
|
||
|
|
if flipped:
|
||
|
|
start, end = (angles[1] + 90, angles[0] + 90)
|
||
|
|
else:
|
||
|
|
start, end = (angles[0] - 90, angles[1] - 90)
|
||
|
|
self.pieslice(coords, start - 90, end - 90, fill)
|
||
|
|
|
||
|
|
if width > 8:
|
||
|
|
# Cover potential gaps between the line and the joint
|
||
|
|
if flipped:
|
||
|
|
gapCoords = [
|
||
|
|
coord_at_angle(point, angles[0] + 90),
|
||
|
|
point,
|
||
|
|
coord_at_angle(point, angles[1] + 90),
|
||
|
|
]
|
||
|
|
else:
|
||
|
|
gapCoords = [
|
||
|
|
coord_at_angle(point, angles[0] - 90),
|
||
|
|
point,
|
||
|
|
coord_at_angle(point, angles[1] - 90),
|
||
|
|
]
|
||
|
|
self.line(gapCoords, fill, width=3)
|
||
|
|
|
||
|
|
def shape(self, shape, fill=None, outline=None):
|
||
|
|
"""(Experimental) Draw a shape."""
|
||
|
|
shape.close()
|
||
|
|
ink, fill = self._getink(outline, fill)
|
||
|
|
if fill is not None:
|
||
|
|
self.draw.draw_outline(shape, fill, 1)
|
||
|
|
if ink is not None and ink != fill:
|
||
|
|
self.draw.draw_outline(shape, ink, 0)
|
||
|
|
|
||
|
|
def pieslice(self, xy, start, end, fill=None, outline=None, width=0):
|
||
|
|
"""Draw a pieslice."""
|
||
|
|
ink, fill = self._getink(outline, fill)
|
||
|
|
if fill is not None:
|
||
|
|
self.draw.draw_pieslice(xy, start, end, fill, 1)
|
||
|
|
if ink is not None and ink != fill:
|
||
|
|
self.draw.draw_pieslice(xy, start, end, ink, 0, width)
|
||
|
|
|
||
|
|
def point(self, xy, fill=None):
|
||
|
|
"""Draw one or more individual pixels."""
|
||
|
|
ink, fill = self._getink(fill)
|
||
|
|
if ink is not None:
|
||
|
|
self.draw.draw_points(xy, ink)
|
||
|
|
|
||
|
|
def polygon(self, xy, fill=None, outline=None):
|
||
|
|
"""Draw a polygon."""
|
||
|
|
ink, fill = self._getink(outline, fill)
|
||
|
|
if fill is not None:
|
||
|
|
self.draw.draw_polygon(xy, fill, 1)
|
||
|
|
if ink is not None and ink != fill:
|
||
|
|
self.draw.draw_polygon(xy, ink, 0)
|
||
|
|
|
||
|
|
def rectangle(self, xy, fill=None, outline=None, width=0):
|
||
|
|
"""Draw a rectangle."""
|
||
|
|
ink, fill = self._getink(outline, fill)
|
||
|
|
if fill is not None:
|
||
|
|
self.draw.draw_rectangle(xy, fill, 1)
|
||
|
|
if ink is not None and ink != fill:
|
||
|
|
self.draw.draw_rectangle(xy, ink, 0, width)
|
||
|
|
|
||
|
|
def _multiline_check(self, text):
|
||
|
|
"""Draw text."""
|
||
|
|
split_character = "\n" if isinstance(text, str) else b"\n"
|
||
|
|
|
||
|
|
return split_character in text
|
||
|
|
|
||
|
|
def _multiline_split(self, text):
|
||
|
|
split_character = "\n" if isinstance(text, str) else b"\n"
|
||
|
|
|
||
|
|
return text.split(split_character)
|
||
|
|
|
||
|
|
def text(
|
||
|
|
self,
|
||
|
|
xy,
|
||
|
|
text,
|
||
|
|
fill=None,
|
||
|
|
font=None,
|
||
|
|
anchor=None,
|
||
|
|
spacing=4,
|
||
|
|
align="left",
|
||
|
|
direction=None,
|
||
|
|
features=None,
|
||
|
|
language=None,
|
||
|
|
stroke_width=0,
|
||
|
|
stroke_fill=None,
|
||
|
|
*args,
|
||
|
|
**kwargs
|
||
|
|
):
|
||
|
|
if self._multiline_check(text):
|
||
|
|
return self.multiline_text(
|
||
|
|
xy,
|
||
|
|
text,
|
||
|
|
fill,
|
||
|
|
font,
|
||
|
|
anchor,
|
||
|
|
spacing,
|
||
|
|
align,
|
||
|
|
direction,
|
||
|
|
features,
|
||
|
|
language,
|
||
|
|
stroke_width,
|
||
|
|
stroke_fill,
|
||
|
|
)
|
||
|
|
|
||
|
|
if font is None:
|
||
|
|
font = self.getfont()
|
||
|
|
|
||
|
|
def getink(fill):
|
||
|
|
ink, fill = self._getink(fill)
|
||
|
|
if ink is None:
|
||
|
|
return fill
|
||
|
|
return ink
|
||
|
|
|
||
|
|
def draw_text(ink, stroke_width=0, stroke_offset=None):
|
||
|
|
coord = xy
|
||
|
|
try:
|
||
|
|
mask, offset = font.getmask2(
|
||
|
|
text,
|
||
|
|
self.fontmode,
|
||
|
|
direction=direction,
|
||
|
|
features=features,
|
||
|
|
language=language,
|
||
|
|
stroke_width=stroke_width,
|
||
|
|
*args,
|
||
|
|
**kwargs,
|
||
|
|
)
|
||
|
|
coord = coord[0] + offset[0], coord[1] + offset[1]
|
||
|
|
except AttributeError:
|
||
|
|
try:
|
||
|
|
mask = font.getmask(
|
||
|
|
text,
|
||
|
|
self.fontmode,
|
||
|
|
direction,
|
||
|
|
features,
|
||
|
|
language,
|
||
|
|
stroke_width,
|
||
|
|
*args,
|
||
|
|
**kwargs,
|
||
|
|
)
|
||
|
|
except TypeError:
|
||
|
|
mask = font.getmask(text)
|
||
|
|
if stroke_offset:
|
||
|
|
coord = coord[0] + stroke_offset[0], coord[1] + stroke_offset[1]
|
||
|
|
self.draw.draw_bitmap(coord, mask, ink)
|
||
|
|
|
||
|
|
ink = getink(fill)
|
||
|
|
if ink is not None:
|
||
|
|
stroke_ink = None
|
||
|
|
if stroke_width:
|
||
|
|
stroke_ink = getink(stroke_fill) if stroke_fill is not None else ink
|
||
|
|
|
||
|
|
if stroke_ink is not None:
|
||
|
|
# Draw stroked text
|
||
|
|
draw_text(stroke_ink, stroke_width)
|
||
|
|
|
||
|
|
# Draw normal text
|
||
|
|
draw_text(ink, 0, (stroke_width, stroke_width))
|
||
|
|
else:
|
||
|
|
# Only draw normal text
|
||
|
|
draw_text(ink)
|
||
|
|
|
||
|
|
def multiline_text(
|
||
|
|
self,
|
||
|
|
xy,
|
||
|
|
text,
|
||
|
|
fill=None,
|
||
|
|
font=None,
|
||
|
|
anchor=None,
|
||
|
|
spacing=4,
|
||
|
|
align="left",
|
||
|
|
direction=None,
|
||
|
|
features=None,
|
||
|
|
language=None,
|
||
|
|
stroke_width=0,
|
||
|
|
stroke_fill=None,
|
||
|
|
):
|
||
|
|
widths = []
|
||
|
|
max_width = 0
|
||
|
|
lines = self._multiline_split(text)
|
||
|
|
line_spacing = (
|
||
|
|
self.textsize("A", font=font, stroke_width=stroke_width)[1] + spacing
|
||
|
|
)
|
||
|
|
for line in lines:
|
||
|
|
line_width, line_height = self.textsize(
|
||
|
|
line,
|
||
|
|
font,
|
||
|
|
direction=direction,
|
||
|
|
features=features,
|
||
|
|
language=language,
|
||
|
|
stroke_width=stroke_width,
|
||
|
|
)
|
||
|
|
widths.append(line_width)
|
||
|
|
max_width = max(max_width, line_width)
|
||
|
|
left, top = xy
|
||
|
|
for idx, line in enumerate(lines):
|
||
|
|
if align == "left":
|
||
|
|
pass # left = x
|
||
|
|
elif align == "center":
|
||
|
|
left += (max_width - widths[idx]) / 2.0
|
||
|
|
elif align == "right":
|
||
|
|
left += max_width - widths[idx]
|
||
|
|
else:
|
||
|
|
raise ValueError('align must be "left", "center" or "right"')
|
||
|
|
self.text(
|
||
|
|
(left, top),
|
||
|
|
line,
|
||
|
|
fill,
|
||
|
|
font,
|
||
|
|
anchor,
|
||
|
|
direction=direction,
|
||
|
|
features=features,
|
||
|
|
language=language,
|
||
|
|
stroke_width=stroke_width,
|
||
|
|
stroke_fill=stroke_fill,
|
||
|
|
)
|
||
|
|
top += line_spacing
|
||
|
|
left = xy[0]
|
||
|
|
|
||
|
|
def textsize(
|
||
|
|
self,
|
||
|
|
text,
|
||
|
|
font=None,
|
||
|
|
spacing=4,
|
||
|
|
direction=None,
|
||
|
|
features=None,
|
||
|
|
language=None,
|
||
|
|
stroke_width=0,
|
||
|
|
):
|
||
|
|
"""Get the size of a given string, in pixels."""
|
||
|
|
if self._multiline_check(text):
|
||
|
|
return self.multiline_textsize(
|
||
|
|
text, font, spacing, direction, features, language, stroke_width
|
||
|
|
)
|
||
|
|
|
||
|
|
if font is None:
|
||
|
|
font = self.getfont()
|
||
|
|
return font.getsize(text, direction, features, language, stroke_width)
|
||
|
|
|
||
|
|
def multiline_textsize(
|
||
|
|
self,
|
||
|
|
text,
|
||
|
|
font=None,
|
||
|
|
spacing=4,
|
||
|
|
direction=None,
|
||
|
|
features=None,
|
||
|
|
language=None,
|
||
|
|
stroke_width=0,
|
||
|
|
):
|
||
|
|
max_width = 0
|
||
|
|
lines = self._multiline_split(text)
|
||
|
|
line_spacing = (
|
||
|
|
self.textsize("A", font=font, stroke_width=stroke_width)[1] + spacing
|
||
|
|
)
|
||
|
|
for line in lines:
|
||
|
|
line_width, line_height = self.textsize(
|
||
|
|
line, font, spacing, direction, features, language, stroke_width
|
||
|
|
)
|
||
|
|
max_width = max(max_width, line_width)
|
||
|
|
return max_width, len(lines) * line_spacing - spacing
|
||
|
|
|
||
|
|
|
||
|
|
def Draw(im, mode=None):
|
||
|
|
"""
|
||
|
|
A simple 2D drawing interface for PIL images.
|
||
|
|
|
||
|
|
:param im: The image to draw in.
|
||
|
|
:param mode: Optional mode to use for color values. For RGB
|
||
|
|
images, this argument can be RGB or RGBA (to blend the
|
||
|
|
drawing into the image). For all other modes, this argument
|
||
|
|
must be the same as the image mode. If omitted, the mode
|
||
|
|
defaults to the mode of the image.
|
||
|
|
"""
|
||
|
|
try:
|
||
|
|
return im.getdraw(mode)
|
||
|
|
except AttributeError:
|
||
|
|
return ImageDraw(im, mode)
|
||
|
|
|
||
|
|
|
||
|
|
# experimental access to the outline API
|
||
|
|
try:
|
||
|
|
Outline = Image.core.outline
|
||
|
|
except AttributeError:
|
||
|
|
Outline = None
|
||
|
|
|
||
|
|
|
||
|
|
def getdraw(im=None, hints=None):
|
||
|
|
"""
|
||
|
|
(Experimental) A more advanced 2D drawing interface for PIL images,
|
||
|
|
based on the WCK interface.
|
||
|
|
|
||
|
|
:param im: The image to draw in.
|
||
|
|
:param hints: An optional list of hints.
|
||
|
|
:returns: A (drawing context, drawing resource factory) tuple.
|
||
|
|
"""
|
||
|
|
# FIXME: this needs more work!
|
||
|
|
# FIXME: come up with a better 'hints' scheme.
|
||
|
|
handler = None
|
||
|
|
if not hints or "nicest" in hints:
|
||
|
|
try:
|
||
|
|
from . import _imagingagg as handler
|
||
|
|
except ImportError:
|
||
|
|
pass
|
||
|
|
if handler is None:
|
||
|
|
from . import ImageDraw2 as handler
|
||
|
|
if im:
|
||
|
|
im = handler.Draw(im)
|
||
|
|
return im, handler
|
||
|
|
|
||
|
|
|
||
|
|
def floodfill(image, xy, value, border=None, thresh=0):
|
||
|
|
"""
|
||
|
|
(experimental) Fills a bounded region with a given color.
|
||
|
|
|
||
|
|
:param image: Target image.
|
||
|
|
:param xy: Seed position (a 2-item coordinate tuple). See
|
||
|
|
:ref:`coordinate-system`.
|
||
|
|
:param value: Fill color.
|
||
|
|
:param border: Optional border value. If given, the region consists of
|
||
|
|
pixels with a color different from the border color. If not given,
|
||
|
|
the region consists of pixels having the same color as the seed
|
||
|
|
pixel.
|
||
|
|
:param thresh: Optional threshold value which specifies a maximum
|
||
|
|
tolerable difference of a pixel value from the 'background' in
|
||
|
|
order for it to be replaced. Useful for filling regions of
|
||
|
|
non-homogeneous, but similar, colors.
|
||
|
|
"""
|
||
|
|
# based on an implementation by Eric S. Raymond
|
||
|
|
# amended by yo1995 @20180806
|
||
|
|
pixel = image.load()
|
||
|
|
x, y = xy
|
||
|
|
try:
|
||
|
|
background = pixel[x, y]
|
||
|
|
if _color_diff(value, background) <= thresh:
|
||
|
|
return # seed point already has fill color
|
||
|
|
pixel[x, y] = value
|
||
|
|
except (ValueError, IndexError):
|
||
|
|
return # seed point outside image
|
||
|
|
edge = {(x, y)}
|
||
|
|
# use a set to keep record of current and previous edge pixels
|
||
|
|
# to reduce memory consumption
|
||
|
|
full_edge = set()
|
||
|
|
while edge:
|
||
|
|
new_edge = set()
|
||
|
|
for (x, y) in edge: # 4 adjacent method
|
||
|
|
for (s, t) in ((x + 1, y), (x - 1, y), (x, y + 1), (x, y - 1)):
|
||
|
|
# If already processed, or if a coordinate is negative, skip
|
||
|
|
if (s, t) in full_edge or s < 0 or t < 0:
|
||
|
|
continue
|
||
|
|
try:
|
||
|
|
p = pixel[s, t]
|
||
|
|
except (ValueError, IndexError):
|
||
|
|
pass
|
||
|
|
else:
|
||
|
|
full_edge.add((s, t))
|
||
|
|
if border is None:
|
||
|
|
fill = _color_diff(p, background) <= thresh
|
||
|
|
else:
|
||
|
|
fill = p != value and p != border
|
||
|
|
if fill:
|
||
|
|
pixel[s, t] = value
|
||
|
|
new_edge.add((s, t))
|
||
|
|
full_edge = edge # discard pixels processed
|
||
|
|
edge = new_edge
|
||
|
|
|
||
|
|
|
||
|
|
def _color_diff(color1, color2):
|
||
|
|
"""
|
||
|
|
Uses 1-norm distance to calculate difference between two values.
|
||
|
|
"""
|
||
|
|
if isinstance(color2, tuple):
|
||
|
|
return sum([abs(color1[i] - color2[i]) for i in range(0, len(color2))])
|
||
|
|
else:
|
||
|
|
return abs(color1 - color2)
|