我正在使用python为来自this的水印图像源代码import Image

import ImageEnhance

import random

def _percent(var):

"""

Just a simple interface to the _val function with a more meaningful name.

"""

return _val(var, True)

def _int(var):

"""

Just a simple interface to the _val function with a more meaningful name.

"""

return _val(var)

def _val(var, is_percent=False):

"""

Tries to determine the appropriate value of a particular variable that is

passed in. If the value is supposed to be a percentage, a whole integer

will be sought after and then turned into a floating point number between

0 and 1. If the value is supposed to be an integer, the variable is cast

into an integer.

"""

try:

if is_percent:

var = float(int(var.strip('%')) / 100.0)

else:

var = int(var)

except ValueError:

raise ValueError('invalid watermark parameter: ' + var)

return var

def reduce_opacity(img, opacity):

"""

Returns an image with reduced opacity.

"""

assert opacity >= 0 and opacity <= 1

if img.mode != 'RGBA':

img = img.convert('RGBA')

else:

img = img.copy()

alpha = img.split()[3]

alpha = ImageEnhance.Brightness(alpha).enhance(opacity)

img.putalpha(alpha)

return img

def determine_scale(scale, img, mark):

"""

Scales an image using a specified ratio or 'F'. If `scale` is 'F', the

image is scaled to be as big as possible to fit in `img` without falling off

the edges. Returns the scaled `mark`.

"""

if scale:

try:

scale = float(scale)

except (ValueError, TypeError):

pass

if type(scale) in (str, unicode) and scale.lower() == 'f':

# scale, but preserve the aspect ratio

scale = min(

float(img.size[0]) / mark.size[0],

float(img.size[1]) / mark.size[1]

)

elif type(scale) not in (float, int):

raise ValueError(

'Invalid scale value "%s"! Valid values are 1) "F" for ratio-preserving scaling and 2) floating-point numbers and integers greater than 0.' % (

scale,))

# determine the new width and height

w = int(mark.size[0] * float(scale)) / 2

h = int(mark.size[1] * float(scale)) / 2

print w, h

# apply the new width and height, and return the new `mark`

return (w, h)

else:

print 'Mark Size', mark.size

return mark.size

def determine_rotation(rotation, mark):

"""

Determines the number of degrees to rotate the watermark image.

"""

if (isinstance(rotation, str) or isinstance(rotation, unicode)) \

and rotation.lower() == 'r':

rotation = random.randint(0, 359)

else:

rotation = _int(rotation)

return rotation

def determine_position(position, img, mark):

"""

Options:

TL: top-left

TR: top-right

BR: bottom-right

BL: bottom-left

C: centered

R: random

X%xY%: relative positioning on both the X and Y axes

X%xY: relative positioning on the X axis and absolute positioning on the

Y axis

XxY%: absolute positioning on the X axis and relative positioning on the

Y axis

XxY: absolute positioning on both the X and Y axes

"""

max_left = max(img.size[0] - mark.size[0], 0)

max_top = max(img.size[1] - mark.size[1], 0)

if not position:

position = 'r'

if isinstance(position, tuple):

left, top = position

elif isinstance(position, str) or isinstance(position, unicode):

position = position.lower()

# corner positioning

if position in ['tl', 'tr', 'br', 'bl']:

if 't' in position:

top = 0

elif 'b' in position:

top = max_top

if 'l' in position:

left = 0

elif 'r' in position:

left = max_left

# center positioning

elif position == 'c':

left = int(max_left / 2)

top = int(max_top / 2)

# random positioning

elif position == 'r':

left = random.randint(0, max_left)

top = random.randint(0, max_top)

# relative or absolute positioning

elif 'x' in position:

left, top = position.split('x')

if '%' in left:

left = max_left * _percent(left)

else:

left = _int(left)

if '%' in top:

top = max_top * _percent(top)

else:

top = _int(top)

print 'top left', left, top

return (left, top)

def watermark(img, mark, position=(0, 0), opacity=1, scale=1.0, tile=False,

greyscale=False, rotation=0, return_name=False, **kwargs):

"""

Adds a watermark to an image.

"""

if opacity < 1:

mark = reduce_opacity(mark, opacity)

if type(scale) != tuple:

scale = determine_scale(scale, img, mark)

print 'mark mode', mark.mode

mark = mark.resize(scale)

if greyscale and mark.mode != 'LA':

mark = mark.convert('LA')

rotation = determine_rotation(rotation, mark)

if rotation != 0:

# give some leeway for rotation overlapping

new_w = mark.size[0]

new_h = mark.size[1]

new_mark = Image.new('RGBA', (new_w, new_h), (0, 0, 0, 0))

# new_mark.putalpha()

# center the watermark in the newly resized image

new_l = (new_w - mark.size[0]) / 2

new_t = (new_h - mark.size[1]) / 2

new_mark.paste(mark, (new_l, new_t))

mark = new_mark.rotate(rotation, Image.BICUBIC, expand=True)

position = determine_position(position, img, mark)

print 'image mode', img.mode

print 'mark mode', mark.mode

if img.mode != 'RGBA':

img = img.convert('RGBA')

print 'image ---', img.mode

alpha = img.split()[3]

alpha = ImageEnhance.Brightness(alpha).enhance(opacity)

img.putalpha(alpha)

# make sure we have a tuple for a position now

assert isinstance(position, tuple), 'Invalid position "%s"!' % position

# create a transparent layer the size of the image and draw the

# watermark in that layer.

layer = Image.new('RGBA', img.size, (0, 0, 0, 0))

if tile:

first_y = position[1] % mark.size[1] - mark.size[1]

first_x = position[0] % mark.size[0] - mark.size[0]

for y in range(first_y, img.size[1], mark.size[1]):

for x in range(first_x, img.size[0], mark.size[0]):

layer.paste(mark, (x, y))

else:

layer.paste(mark, position)

# composite the watermark with the layer

return Image.composite(layer, img, layer)

def test():

im = Image.open('/home/chanhle/0450034_a (4th copy).jpg')

mark = Image.open('/home/chanhle/UMA LOGO.png')

# im.save('/home/chanhle/0120047_a.png')

watermark(im, mark,

position='C',

opacity=0.8,

scale='f',

rotation=45).save('/home/chanhle/test3.jpg', 'JPEG')

if __name__ == '__main__':

test()

这是我要加水印的图像

这是logo

运行以上代码时的结果

结果当我使用在线工具时，它很漂亮。

正如你在结果中看到的标志水印不够尖锐，它不是美丽的，因为我的预期。

如何提高这种质量？

感谢支持。在