"""image_tools.py - Various image manipulations."""
import sys
import os
import operator
import itertools
import bisect
import math
import gtk
import PIL.Image as Image
import PIL.ImageEnhance as ImageEnhance
import PIL.ImageOps as ImageOps
from mcomix.preferences import prefs
# File formats supported by PyGTK (sorted list of extensions)
_supported_formats = sorted(
[ extension.lower() for extlist in
itertools.imap(operator.itemgetter("extensions"),
gtk.gdk.pixbuf_get_formats())
for extension in extlist])
def fit_in_rectangle(src, width, height, scale_up=False, rotation=0):
"""Scale (and return) a pixbuf so that it fits in a rectangle with
dimensions <width> x <height>. A negative <width> or <height>
means an unbounded dimension - both cannot be negative.
If <rotation> is 90, 180 or 270 we rotate <src> first so that the
rotated pixbuf is fitted in the rectangle.
Unless <scale_up> is True we don't stretch images smaller than the
given rectangle.
If <src> has an alpha channel it gets a checkboard background.
"""
# "Unbounded" really means "bounded to 10000 px" - for simplicity.
# MComix would probably choke on larger images anyway.
if width < 0:
width = 100000
elif height < 0:
height = 100000
width = max(width, 1)
height = max(height, 1)
if rotation in (90, 270):
width, height = height, width
src_width = src.get_width()
src_height = src.get_height()
if not scale_up and src_width <= width and src_height <= height:
if src.get_has_alpha():
if prefs['checkered bg for transparent images']:
src = src.composite_color_simple(src_width, src_height,
prefs['scaling quality'], 255, 8, 0x777777, 0x999999)
else:
src = src.composite_color_simple(src_width, src_height,
prefs['scaling quality'], 255, 1024, 0xFFFFFF, 0xFFFFFF)
else:
if float(src_width) / width > float(src_height) / height:
height = int(max(src_height * width / src_width, 1))
else:
width = int(max(src_width * height / src_height, 1))
if src.get_has_alpha():
if prefs['checkered bg for transparent images']:
src = src.composite_color_simple(width, height,
prefs['scaling quality'], 255, 8, 0x777777, 0x999999)
else:
src = src.composite_color_simple(width, height,
prefs['scaling quality'], 255, 1024, 0xFFFFFF, 0xFFFFFF)
elif width != src_width or height != src_height:
src = src.scale_simple(width, height, prefs['scaling quality'])
if rotation == 90:
src = src.rotate_simple(gtk.gdk.PIXBUF_ROTATE_CLOCKWISE)
elif rotation == 180:
src = src.rotate_simple(gtk.gdk.PIXBUF_ROTATE_UPSIDEDOWN)
elif rotation == 270:
src = src.rotate_simple(gtk.gdk.PIXBUF_ROTATE_COUNTERCLOCKWISE)
return src
def get_double_page_rectangle(width_1, height_1, width_2, height_2):
h1 = float(height_1)
w1 = float(width_1)
h2 = float(height_2)
w2 = float(width_2)
target_tan = h2 * h1 / (w1*h2 + h1*w2)
height = max(height_1, height_2)
width = int(math.floor(height / target_tan)) + 2 # 2px between pages
return width, height
def add_border(pixbuf, thickness, colour=0x000000FF):
"""Return a pixbuf from <pixbuf> with a <thickness> px border of
<colour> added.
"""
canvas = gtk.gdk.Pixbuf(gtk.gdk.COLORSPACE_RGB, True, 8,
pixbuf.get_width() + thickness * 2,
pixbuf.get_height() + thickness * 2)
canvas.fill(colour)
pixbuf.copy_area(0, 0, pixbuf.get_width(), pixbuf.get_height(),
canvas, thickness, thickness)
return canvas
def get_most_common_edge_colour(pixbufs, edge=2):
"""Return the most commonly occurring pixel value along the four edges
of <pixbuf>. The return value is a sequence, (r, g, b), with 16 bit
values. If <pixbuf> is a tuple, the edges will be computed from
both the left and the right image.
Note: This could be done more cleanly with subpixbuf(), but that
doesn't work as expected together with get_pixels().
"""
def group_colors(colors, steps=10):
""" This rounds a list of colors in C{colors} to the next nearest value,
i.e. 128, 83, 10 becomes 130, 85, 10 with C{steps}=5. This compensates for
dirty colors where no clear dominating color can be made out.
@return: The color that appears most often in the prominent group."""
# Start group
group = (0, 0, 0)
# List of (count, color) pairs, group contains most colors
colors_in_prominent_group = []
color_count_in_prominent_group = 0
# List of (count, color) pairs, current color group
colors_in_group = []
color_count_in_group = 0
for count, color in colors:
# Round color
rounded = [0] * len(color)
for i, color_value in enumerate(color):
if steps % 2 == 0:
middle = steps // 2
else:
middle = steps // 2 + 1
remainder = color_value % steps
if remainder >= middle:
color_value = color_value + (steps - remainder)
else:
color_value = color_value - remainder
rounded[i] = min(255, max(0, color_value))
# Change prominent group if necessary
if rounded == group:
# Color still fits in the previous color group
colors_in_group.append((count, color))
color_count_in_group += count
else:
# Color group changed, check if current group has more colors
# than last group
if color_count_in_group > color_count_in_prominent_group:
colors_in_prominent_group = colors_in_group
color_count_in_prominent_group = color_count_in_group
group = rounded
colors_in_group = [ (count, color) ]
color_count_in_group = count
# Cleanup if only one edge color group was found
if color_count_in_group > color_count_in_prominent_group:
colors_in_prominent_group = colors_in_group
colors_in_prominent_group.sort(key=operator.itemgetter(0), reverse=True)
# List is now sorted by color count, first color appears most often
return colors_in_prominent_group[0][1]
def get_edge_pixbuf(pixbuf, side, edge):
""" Returns a pixbuf corresponding to the side passed in <side>.
Valid sides are 'left', 'right', 'top', 'bottom'. """
width = pixbuf.get_width()
height = pixbuf.get_height()
edge = min(edge, width, height)
subpix = gtk.gdk.Pixbuf(gtk.gdk.COLORSPACE_RGB,
pixbuf.get_has_alpha(), 8, edge, height)
if side == 'left':
pixbuf.copy_area(0, 0, edge, height, subpix, 0, 0)
elif side == 'right':
pixbuf.copy_area(width - edge, 0, edge, height, subpix, 0, 0)
elif side == 'top':
pixbuf.copy_area(0, 0, width, edge, subpix, 0, 0)
elif side == 'bottom':
pixbuf.copy_area(0, height - edge, width, edge, subpix, 0, 0)
else:
assert False, 'Invalid edge side'
return subpix
if not pixbufs:
return (0, 0, 0)
if not isinstance(pixbufs, (tuple, list)):
left_edge = get_edge_pixbuf(pixbufs, 'left', edge)
right_edge = get_edge_pixbuf(pixbufs, 'right', edge)
else:
assert len(pixbufs) == 2, 'Expected two pages in list'
left_edge = get_edge_pixbuf(pixbufs[0], 'left', edge)
right_edge = get_edge_pixbuf(pixbufs[1], 'right', edge)
# Find all edge colors. Color count is separate for all four edges
ungrouped_colors = []
for edge in (left_edge, right_edge):
im = pixbuf_to_pil(edge)
ungrouped_colors.extend(im.getcolors(im.size[0] * im.size[1]))
# Sum up colors from all edges
ungrouped_colors.sort(key=operator.itemgetter(1))
most_used = group_colors(ungrouped_colors)
return [color * 257 for color in most_used]
def pil_to_pixbuf(image):
"""Return a pixbuf created from the PIL <image>."""
if image.mode.startswith('RGB'):
imagestr = image.tostring()
IS_RGBA = image.mode == 'RGBA'
return gtk.gdk.pixbuf_new_from_data(imagestr, gtk.gdk.COLORSPACE_RGB,
IS_RGBA, 8, image.size[0], image.size[1],
(IS_RGBA and 4 or 3) * image.size[0])
else:
imagestr = image.convert('RGB').tostring()
return gtk.gdk.pixbuf_new_from_data(imagestr, gtk.gdk.COLORSPACE_RGB,
False, 8, image.size[0], image.size[1],
3 * image.size[0])
def pixbuf_to_pil(pixbuf):
"""Return a PIL image created from <pixbuf>."""
dimensions = pixbuf.get_width(), pixbuf.get_height()
stride = pixbuf.get_rowstride()
pixels = pixbuf.get_pixels()
mode = pixbuf.get_has_alpha() and 'RGBA' or 'RGB'
return Image.frombuffer(mode, dimensions, pixels, 'raw', mode, stride, 1)
def load_pixbuf(path):
""" Loads a pixbuf from a given image file. Works around GTK's
slowness on Win32 by using PIL for loading instead and
converting it afterwards. """
if sys.platform == 'win32' and gtk.gtk_version > (2, 18, 2):
pil_img = Image.open(path)
return pil_to_pixbuf(pil_img)
else:
return gtk.gdk.pixbuf_new_from_file(path)
def load_pixbuf_size(path, width, height):
""" Loads a pixbuf from a given image file and scale it to fit
inside (width, height). """
try:
return fit_in_rectangle(load_pixbuf(path), width, height)
except:
return None
def load_pixbuf_data(imgdata):
""" Loads a pixbuf from the data passed in <imgdata>. """
loader = gtk.gdk.PixbufLoader()
loader.write(imgdata, len(imgdata))
loader.close()
return loader.get_pixbuf()
def enhance(pixbuf, brightness=1.0, contrast=1.0, saturation=1.0,
sharpness=1.0, autocontrast=False):
"""Return a modified pixbuf from <pixbuf> where the enhancement operations
corresponding to each argument has been performed. A value of 1.0 means
no change. If <autocontrast> is True it overrides the <contrast> value,
but only if the image mode is supported by ImageOps.autocontrast (i.e.
it is L or RGB.)
"""
im = pixbuf_to_pil(pixbuf)
if brightness != 1.0:
im = ImageEnhance.Brightness(im).enhance(brightness)
if autocontrast and im.mode in ('L', 'RGB'):
im = ImageOps.autocontrast(im, cutoff=0.1)
elif contrast != 1.0:
im = ImageEnhance.Contrast(im).enhance(contrast)
if saturation != 1.0:
im = ImageEnhance.Color(im).enhance(saturation)
if sharpness != 1.0:
im = ImageEnhance.Sharpness(im).enhance(sharpness)
return pil_to_pixbuf(im)
def get_implied_rotation(pixbuf):
"""Return the implied rotation of the pixbuf, as given by the pixbuf's
orientation option (the value of which is based on EXIF data etc.).
The implied rotation is the angle (in degrees) that the raw pixbuf should
be rotated in order to be displayed "correctly". E.g. a photograph taken
by a camera that is held sideways might store this fact in its EXIF data,
and the pixbuf loader will set the orientation option correspondingly.
"""
orientation = pixbuf.get_option('orientation')
if orientation == '3':
return 180
elif orientation == '6':
return 90
elif orientation == '8':
return 270
return 0
def combine_pixbufs( pixbuf1, pixbuf2, are_in_manga_mode ):
if are_in_manga_mode:
r_source_pixbuf = pixbuf1
l_source_pixbuf = pixbuf2
else:
l_source_pixbuf = pixbuf1
r_source_pixbuf = pixbuf2
has_alpha = False
if l_source_pixbuf.get_property( 'has-alpha' ) or \
r_source_pixbuf.get_property( 'has-alpha' ):
has_alpha = True
bits_per_sample = 8
l_source_pixbuf_width = l_source_pixbuf.get_property( 'width' )
r_source_pixbuf_width = r_source_pixbuf.get_property( 'width' )
l_source_pixbuf_height = l_source_pixbuf.get_property( 'height' )
r_source_pixbuf_height = r_source_pixbuf.get_property( 'height' )
new_width = l_source_pixbuf_width + r_source_pixbuf_width
new_height = max( l_source_pixbuf_height, r_source_pixbuf_height )
new_pix_buf = gtk.gdk.Pixbuf( gtk.gdk.COLORSPACE_RGB, has_alpha,
bits_per_sample, new_width, new_height )
l_source_pixbuf.copy_area( 0, 0, l_source_pixbuf_width,
l_source_pixbuf_height,
new_pix_buf, 0, 0 )
r_source_pixbuf.copy_area( 0, 0, r_source_pixbuf_width,
r_source_pixbuf_height,
new_pix_buf, l_source_pixbuf_width, 0 )
return new_pix_buf
def is_image_file(path):
"""Return True if the file at <path> is an image file recognized by PyGTK.
"""
ext = os.path.splitext(path)[1][1:].lower()
ext_index = bisect.bisect_left(_supported_formats, ext)
return ext_index != len(_supported_formats) and _supported_formats[ext_index] == ext
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